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1.  A dedicated visual pathway for prey detection in larval zebrafish 
eLife  null;3:e04878.
Zebrafish larvae show characteristic prey capture behavior in response to small moving objects. The neural mechanism used to recognize objects as prey remains largely unknown. We devised a machine learning behavior classification system to quantify hunting kinematics in semi-restrained animals exposed to a range of virtual stimuli. Two-photon calcium imaging revealed a small visual area, AF7, that was activated specifically by the optimal prey stimulus. This pretectal region is innervated by two types of retinal ganglion cells, which also send collaterals to the optic tectum. Laser ablation of AF7 markedly reduced prey capture behavior. We identified neurons with arbors in AF7 and found that they projected to multiple sensory and premotor areas: the optic tectum, the nucleus of the medial longitudinal fasciculus (nMLF) and the hindbrain. These findings indicate that computations in the retina give rise to a visual stream which transforms sensory information into a directed prey capture response.
DOI: http://dx.doi.org/10.7554/eLife.04878.001
eLife digest
Our ability to recognize objects, and to respond instinctively to them, is something that is not fully understood. For example, seeing your favorite dessert could trigger an irresistible urge to eat it. Yet precisely how the image of the dessert could trigger an inner desire to indulge is a question that has so far eluded scientists. This compelling question also applies to the animal kingdom. Predators often demonstrate a typical hunting behavior upon seeing their prey from a distance. But just how the image of the prey triggers this hunting behavior is not known.
Semmelhack et al. have now investigated this question by looking at the hunting behavior of zebrafish larvae. The larvae's prey is a tiny microbe that resembles a small moving dot. When the larvae encounter something that looks like their prey, they demonstrate a hardwired hunting response towards it. The hunting behavior consists of a series of swimming maneuvers to help the larvae successfully capture their prey.
Semmelhack et al. used prey decoys to lure the zebrafish larvae, and video recordings to monitor the larvae's response. During the recordings, the larvae were embedded in a bed of jelly with only their tails free to move. The larvae's tail movements were recorded, and because the larvae are completely transparent, their brain activity could be visually monitored at the same time using calcium dyes.
Using this approach, Semmelhack et al. identified a specific area of the brain that is responsible for triggering the larvae's hunting behavior. It turns out that this brain region forms a circuit that directly connects the retina at the back of the eye to nerve centers that control hunting maneuvers. So when the larva sees its prey, this circuit could directly trigger the larva's hunting behavior. When the circuit was specifically destroyed with a laser, this instinctive hunting response was impaired.
These findings suggest that predators have a distinct brain circuit that hardwires their hunting response to images of their prey. Future studies would involve understanding precisely how this circuit coordinates the larvae's complex hunting behavior.
DOI: http://dx.doi.org/10.7554/eLife.04878.002
doi:10.7554/eLife.04878
PMCID: PMC4281881  PMID: 25490154
visual system; behavior; retinal ganglion cells; pretectum; optic tectum; Zebrafish
2.  Specialized areas for value updating and goal selection in the primate orbitofrontal cortex 
eLife  null;4:e11695.
The macaque orbitofrontal cortex (OFC) is essential for selecting goals based on current, updated values of expected reward outcomes. As monkeys consume a given type of reward to satiety, its value diminishes, and OFC damage impairs the ability to shift goal choices away from devalued outcomes. To examine the contributions of OFC’s components to goal selection, we reversibly inactivated either its anterior (area 11) or posterior (area 13) parts. We found that neurons in area 13 must be active during the selective satiation procedure to enable the updating of outcome valuations. After this updating has occurred, however, area 13 is not needed to select goals based on this knowledge. In contrast, neurons in area 11 do not need to be active during the value-updating process. Instead, inactivation of this area during choices causes an impairment. These findings demonstrate selective and complementary specializations within the OFC.
DOI: http://dx.doi.org/10.7554/eLife.11695.001
eLife digest
Everyone knows that somehow, somewhere, the brain translates knowledge into action. In some people, however, knowledge and action become disconnected. These people behave in a way that either ignores or contradicts the knowledge that they have. They know what to do and can explain it to others, but – when the time comes to act – they do something else, something wrong.
Murray et al. have now investigated how a brain region called the orbitofrontal cortex helps to link knowledge and action in macaque monkeys, which, unlike rodents, have all of the main brain areas that make up the orbitofrontal cortex of humans. The monkeys learned to associate images with different types of food, and then performed a task where they chose between two images in order to get the food they wanted. On some days, one of the foods was less ‘valuable’ because the monkeys had already eaten a lot of it. In these circumstances, monkeys chose fewer of the images associated with that food.
By temporarily inactivating either the front or back region of the monkey’s orbitofrontal cortex at different times, Murray et al. showed that these regions make different contributions to decision making. Inactivating the back region of the orbitofrontal cortex disrupted the ability of monkeys to update their knowledge about the value of a particular foodstuff. However, inactivating the front part of the orbitofrontal cortex disrupted their ability to use this knowledge to select the images that led to the most valuable food. This contradicts the widely held belief that the orbitofrontal cortex acts as a single entity to update values and translate this knowledge into action.
Future work will need to investigate how, having translated knowledge into a chosen action, the orbitofrontal cortex stimulates the motor areas of the brain to generate the movements needed to perform that action.
DOI: http://dx.doi.org/10.7554/eLife.11695.002
doi:10.7554/eLife.11695
PMCID: PMC4739757  PMID: 26673891
macaque monkey; decision making; reinforcer devaluation; goal neglect; Other
3.  State of the art of current 3-D scoliosis classifications: a systematic review from a clinical perspective 
Scoliosis is a complex three dimensional (3D) deformity: the current lack of a 3D classification could hide something fundamental for scoliosis prognosis and treatment. A clear picture of the actually existing 3D classifications lacks. The aim of this systematic review was to identify all the 3D classification systems proposed until now in the literature with the aim to identify similarities and differences mainly in a clinical perspective.
After a MEDLINE Data Base review, done in November 2013 using the search terms “Scoliosis/classification” [Mesh] and “scoliosis/classification and Imaging, three dimensional” [Mesh], 8 papers were included with a total of 1164 scoliosis patients, 23 hyperkyphosis and 25 controls, aged between 8 and 20 years, with curves from 10° to 81° Cobb, and various curve patterns. Six studies looked at the whole 3D spine and found classificatory parameters according to planes, angles and rotations, including: Plane of Maximal Curvature (PMC), Best Fit Plane, Cobb angles in bodily plane and PMC, Axial rotation of the apical vertebra and of the PMC, and geometric 3D torsion. Two studies used the regional (spinal) Top View of the spine and found classificatory parameters according to its geometrical properties (area, direction and barycenter) including: Ratio of the frontal and the sagittal size, Phase, Directions (total, thoracic and lumbar), and Shift. It was possible to find similarities among 10 out of the 16 the sub-groups identified by different authors with different methods in different populations.
In summation, the state of the art of 3D classification systems include 8 studies which showed some comparability, even though of low level. The most useful one in clinical everyday practice, is far from being defined. More than 20 years passed since the definition of the third dimension of the scoliosis deformity, now the time has come for clinicians and bioengineers to start some real clinical application, and develop means to make this approach an everyday tool.
doi:10.1186/s12984-015-0083-8
PMCID: PMC4609046  PMID: 26475324
Spine disorders; Scoliosis deformity; 3D classification; Review; Imaging
4.  Cortical regulation of cell size by a sizer cdr2p 
eLife  2014;3:e02040.
Cells can, in principle, control their size by growing to a specified size before commencing cell division. How any cell actually senses its own size remains poorly understood. The fission yeast Schizosaccharomyces pombe are rod-shaped cells that grow to ∼14 µm in length before entering mitosis. In this study, we provide evidence that these cells sense their surface area as part of this size control mechanism. We show that cells enter mitosis at a certain surface area, as opposed to a certain volume or length. A peripheral membrane protein kinase cdr2p has properties of a dose-dependent ‘sizer’ that controls mitotic entry. As cells grow, the local cdr2p concentration in nodes at the medial cortex accumulates as a measure of cell surface area. Our findings, which challenge a previously proposed pom1p gradient model, lead to a new model in which cells sense their size by using cdr2p to probe the surface area over the whole cell and relay this information to the medial cortex.
DOI: http://dx.doi.org/10.7554/eLife.02040.001
eLife digest
Although different types of cells come in a variety of shapes and sizes, most cells are able to maintain a fairly consistent size and shape as they grow and divide. For example, the rod-shaped cells of the fission yeast S. pombe grow to be 14 microns long before dividing in the middle to form two new cells. This prevents any single cell becoming too large or small.
A similar phenomenon has been observed in other types of cells, so it is clear that cells must be able to measure their own size, and then use that information to trigger cell division. A number of proteins that regulate cell size and cell division in fission yeast have now been identified. These proteins form a pathway in which a protein called pom1p inhibits another protein, cdr2p, which in turn causes a third protein, cdk1p, to start the process of cell division. However, the details of the measurement process and the property that the cells are actually measuring—surface area, volume, mass or something else—remain mysterious.
Pan et al. have now used imaging techniques and mathematical modeling to probe the distribution and movements of proteins in fission yeast cells. Their results do not support a previous model in which the cell uses the gradient of pom1p as a ruler to measure cell length. Rather, Pan et al. propose a new model in which the level of cdr2p is used to sense the size of the cell. Individual molecules of cdr2p come together to from clusters called nodes on the cell membrane. As the cell grows larger, more and more cdr2p proteins accumulate in these nodes, which are found in a band around the middle of the cell. When the cells reaches a critical cell size, the increased concentration of cdr2p at these nodes may help to trigger the start of cell division.
By examining cells that grow at different rates, Pan et al. show that the rate of accumulation of cdr2p in the nodes depends on how big the cells are, rather than on the length of time that has elapsed. Analysis of fission yeast cells of different shapes shows that cell division starts when the surface area of the cell grows to a certain value, as opposed to starting when the volume or length reach a given value.
Pan et al. also show that cdr2p binds to all parts of the cell membrane, not just to the nodes near the middle, and go on to provide a simple mathematical model showing how this property can allow cells to measure their surface area. However, as Pan et al. point out, this is probably just one component of a larger mechanism that tells cells when they need to divide.
DOI: http://dx.doi.org/10.7554/eLife.02040.002
doi:10.7554/eLife.02040
PMCID: PMC3956294  PMID: 24642412
cell size control; protein kinase; plasma membrane; cell cycle; S. pombe
5.  Lis1 regulates dynein by sterically blocking its mechanochemical cycle 
eLife  null;3:e03372.
Regulation of cytoplasmic dynein's motor activity is essential for diverse eukaryotic functions, including cell division, intracellular transport, and brain development. The dynein regulator Lis1 is known to keep dynein bound to microtubules; however, how this is accomplished mechanistically remains unknown. We have used three-dimensional electron microscopy, single-molecule imaging, biochemistry, and in vivo assays to help establish this mechanism. The three-dimensional structure of the dynein–Lis1 complex shows that binding of Lis1 to dynein's AAA+ ring sterically prevents dynein's main mechanical element, the ‘linker’, from completing its normal conformational cycle. Single-molecule experiments show that eliminating this block by shortening the linker to a point where it can physically bypass Lis1 renders single dynein motors insensitive to regulation by Lis1. Our data reveal that Lis1 keeps dynein in a persistent microtubule-bound state by directly blocking the progression of its mechanochemical cycle.
DOI: http://dx.doi.org/10.7554/eLife.03372.001
eLife digest
Cells use motor proteins to move ‘cargo’ from one location to another inside the cell. This cargo can range in size from a single macromolecule to something as large as the nucleus of the cell. A motor protein called dynein is the largest and least understood of the motor proteins found in cells.
Dynein molecules work in pairs to take ‘steps’ along tracks called microtubules. Dynein contains two domains: a motor domain, which is responsible for generating movement, and a ‘tail’ domain to which the cargo is attached. The motor domain is composed of a ring-like shape and two appendages—the stalk and the linker. The linker undergoes large-scale movements relative to the ring that transmits force to the tail domain.
Dynein also interacts with various accessory proteins to do its job inside the cell. One of these is a protein called Lis1 that is found across a wide range of species from yeast to humans. Defects in the gene for Lis1 result in brain developmental disorders in humans. However, it is not clear how the Lis1 protein influences the activity of dynein.
Now Toropova, Zou et al. have visualized the structure of dynein bound to Lis1 and compared it with the structure of dynein on its own in order to work out if dynein changes its shape as a result of binding to Lis1. These experiments show that when Lis1 binds to dynein, it physically blocks the linker, preventing it from making contacts with the ring-like shape that are important for the normal function of the motor.
To test the idea that this physical block is responsible for dynein molecules spending a relatively long time attached to their microtubules, Toropova, Zou et al. shortened the linker to a point where the Lis1 protein could no longer block it: this resulted in a dynein motor that was no longer sensitive to Lis1. A challenge for the future is to understand, at a molecular level, how the Lis1-mediated slowing down of dynein affects the multiple functions the motor carries out in a cell.
DOI: http://dx.doi.org/10.7554/eLife.03372.002
doi:10.7554/eLife.03372
PMCID: PMC4359366  PMID: 25380312
dynein; electron microscopy; Lis1; microtubules; structure; S. cerevisiae
6.  MicroRNAs down-regulate homologous recombination in the G1 phase of cycling cells to maintain genomic stability 
eLife  2014;3:e02445.
Homologous recombination (HR)-mediated repair of DNA double-strand break (DSB)s is restricted to the post-replicative phases of the cell cycle. Initiation of HR in the G1 phase blocks non-homologous end joining (NHEJ) impairing DSB repair. Completion of HR in G1 cells can lead to the loss-of-heterozygosity (LOH), which is potentially carcinogenic. We conducted a gain-of-function screen to identify miRNAs that regulate HR-mediated DSB repair, and of these miRNAs, miR-1255b, miR-148b*, and miR-193b* specifically suppress the HR-pathway in the G1 phase. These miRNAs target the transcripts of HR factors, BRCA1, BRCA2, and RAD51, and inhibiting miR-1255b, miR-148b*, and miR-193b* increases expression of BRCA1/BRCA2/RAD51 specifically in the G1-phase leading to impaired DSB repair. Depletion of CtIP, a BRCA1-associated DNA end resection protein, rescues this phenotype. Furthermore, deletion of miR-1255b, miR-148b*, and miR-193b* in independent cohorts of ovarian tumors correlates with significant increase in LOH events/chromosomal aberrations and BRCA1 expression.
DOI: http://dx.doi.org/10.7554/eLife.02445.001
eLife digest
The DNA in a cell is damaged thousands of times every day. One of the most serious types of damage involves something breaking both of the strands in the double helix. Such a double-strand break can delete genes or even kill the cell. In fact, conventional cancer therapy kills cancer cells by causing irreparable double-strand breaks. Conversely, a normal cell that is constantly exposed to DNA damaging agents can become a tumor if double-strand breaks are incorrectly repaired. An efficient and accurate double-strand break repair system needs to be in place to prevent this transformation. Therefore, an in-depth understanding of double-strand break repair and the factors involved are important for both gaining insight into the cause of cancer and to improve cancer therapy.
Cells have evolved several different ways to detect and repair double-strand breaks. A method called homologous recombination, for example, uses an undamaged DNA molecule as a template that can be copied to make new DNA. Since it needs a readily available DNA template, this method only works in phases of the cell growth cycle where there are many copies of DNA—that is, in the post-DNA replication phases. In particular, homologous recombination does not work during the pre-replication, G1 phase. If homologous recombination is attempted during G1, it will block the other methods employed by cells to repair broken strands of DNA.
An important challenge is to understand how homologous recombination is restricted to particular parts of the cell cycle. Although certain proteins associated with the early stages of double-strand repair are thought to determine the type of DNA repair that occurs, the details of this process are not fully understood.
One group of molecules that are thought to be involved are microRNAs, which normally limit the number of proteins produced from certain genes. However, since a single microRNA molecule can be associated with several proteins, and since a single protein can be associated with several microRNA molecules, it has proved difficult to establish the exact effects of a specific microRNA molecule.
Choi et al. now show that seven microRNA molecules can control homologous recombination, and three microRNAs in particular restrict homologous recombination during the G1 phase of the cell cycle. If these microRNAs are inhibited during the G1 phase, which allows homologous recombination to start, and counter-intuitively more double-stranded breaks are seen. However, if a gene involved in starting homologous repair–called CtIP—is silenced while the microRNAs are inhibited, then the DNA breaks are repaired. Exactly, how the microRNA molecules produce different effects during different phases of the cell cycle will be need to be investigated by future studies.
DOI: http://dx.doi.org/10.7554/eLife.02445.002
doi:10.7554/eLife.02445
PMCID: PMC4031983  PMID: 24843000
DNA repair; BRCA1; cell cycle; human; mouse
7.  Cost-Effectiveness of Interventions to Promote Physical Activity: A Modelling Study 
PLoS Medicine  2009;6(7):e1000110.
Linda Cobiac and colleagues model the costs and health outcomes associated with interventions to improve physical activity in the population, and identify specific interventions that are likely to be cost-saving.
Background
Physical inactivity is a key risk factor for chronic disease, but a growing number of people are not achieving the recommended levels of physical activity necessary for good health. Australians are no exception; despite Australia's image as a sporting nation, with success at the elite level, the majority of Australians do not get enough physical activity. There are many options for intervention, from individually tailored advice, such as counselling from a general practitioner, to population-wide approaches, such as mass media campaigns, but the most cost-effective mix of interventions is unknown. In this study we evaluate the cost-effectiveness of interventions to promote physical activity.
Methods and Findings
From evidence of intervention efficacy in the physical activity literature and evaluation of the health sector costs of intervention and disease treatment, we model the cost impacts and health outcomes of six physical activity interventions, over the lifetime of the Australian population. We then determine cost-effectiveness of each intervention against current practice for physical activity intervention in Australia and derive the optimal pathway for implementation. Based on current evidence of intervention effectiveness, the intervention programs that encourage use of pedometers (Dominant) and mass media-based community campaigns (Dominant) are the most cost-effective strategies to implement and are very likely to be cost-saving. The internet-based intervention program (AUS$3,000/DALY), the GP physical activity prescription program (AUS$12,000/DALY), and the program to encourage more active transport (AUS$20,000/DALY), although less likely to be cost-saving, have a high probability of being under a AUS$50,000 per DALY threshold. GP referral to an exercise physiologist (AUS$79,000/DALY) is the least cost-effective option if high time and travel costs for patients in screening and consulting an exercise physiologist are considered.
Conclusions
Intervention to promote physical activity is recommended as a public health measure. Despite substantial variability in the quantity and quality of evidence on intervention effectiveness, and uncertainty about the long-term sustainability of behavioural changes, it is highly likely that as a package, all six interventions could lead to substantial improvement in population health at a cost saving to the health sector.
Please see later in the article for Editors' Summary
Editors' Summary
Background
The human body needs regular physical activity throughout life to stay healthy. Physical activity—any bodily movement produced by skeletal muscles that uses energy—helps to maintain a healthy body weight and to prevent or delay heart disease, stroke, type 2 diabetes, colon cancer, and breast cancer. In addition, physically active people feel better and live longer than physically inactive people. For an adult, 30 minutes of moderate physical activity—walking briskly, gardening, swimming, or cycling—at least five times a week is sufficient to promote and maintain health. But at least 60% of the world's population does not do even this modest amount of physical activity. The daily lives of people in both developed and developing countries are becoming increasingly sedentary. People are sitting at desks all day instead of doing manual labor; they are driving to work in cars instead of walking or cycling; and they are participating less in physical activities during their leisure time.
Why Was This Study Done?
In many countries, the chronic diseases that are associated with physical inactivity are now a major public-health problem; globally, physical inactivity causes 1.9 million deaths per year. Clearly, something has to be done about this situation. Luckily, there is no shortage of interventions designed to promote physical activity, ranging from individual counseling from general practitioners to mass-media campaigns. But which intervention or package of interventions will produce the optimal population health benefits relative to cost? Although some studies have examined the cost-effectiveness of individual interventions, different settings for analysis and use of different methods and assumptions make it difficult to compare results and identify which intervention approaches should be give priority by policy makers. Furthermore, little is known about the cost-effectiveness of packages of interventions. In this study, the researchers investigate the cost-effectiveness in Australia (where physical inactivity contributes to 10% of deaths) of a package of interventions designed to promote physical activity in adults using a standardized approach (ACE-Prevention) to the assessment of the cost-effectiveness of health-care interventions.
What Did the Researchers Do and Find?
The researchers selected six interventions for their study: general practitioner “prescription” of physical activity; general practitioner referral to an exercise physiologist; a mass-media campaign to promote physical activity; the TravelSmart car use reduction program; a campaign to encourage the use of pedometers to increase physical activity; and an internet-based program. Using published data on the effects of physical activity on the amount of illness and death caused by breast and colon cancer, heart disease, stroke, and type 2 diabetes and on the effectiveness of each intervention, the researchers calculated the health outcomes of each intervention in disability-adjusted life years (DALY; a year of healthy life lost because of premature death or disability) averted over the lifetime of the Australian population. They also calculated the costs associated with each intervention offset by the costs associated with the five conditions listed above. These analyses showed that the pedometer program and the mass-media campaign were likely to be the most cost-effective interventions. These interventions were also most likely to be cost-saving. Referral to an exercise physiologist was the least cost-effective intervention. The other three interventions, though unlikely to be cost-saving, were likely to be cost-effective. Finally, a package of all six interventions would be cost-effective and would avert 61,000 DALYs, a third of what could be achieved if every Australian did 30 minutes of physical activity five times a week.
What Do These Findings Mean?
As in all modeling studies, these findings depend on the quality of the data and on the assumptions included by the researchers in their calculations. Unfortunately, there was substantial variability in the quantity and quality of evidence on the effectiveness of each intervention and uncertainty about the long-term effects of each intervention. Nevertheless, the findings presented in this study suggest that the assessment of the cost-effectiveness of a combination of interventions designed to promote physical activity might provide policy makers with some guidance about the best way to reduce the burden of disease caused by physical inactivity. More specifically, for Australia, these findings suggest that the package of the six interventions considered here is likely to provide a cost-effective way to substantially improve the health of the nation.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000110.
The World Health Organization provides information about physical activity and health (in several languages); it also provides an explanation of DALYs
The US Centers for Disease Control and Prevention provides information on physical activity for different age groups and for health professionals
The UK National Health Service information source Choices also explains the benefits of regular physical activity
MedlinePlus has links to other resources about exercise and physical fitness (in English and Spanish)
The University of Queensland Web site has more information on ACE-Prevention (Assessing Cost-Effectiveness Prevention)
doi:10.1371/journal.pmed.1000110
PMCID: PMC2700960  PMID: 19597537
8.  Guidelines, Editors, Pharma And The Biological Paradigm Shift 
Mens Sana Monographs  2007;5(1):27-30.
Private investment in biomedical research has increased over the last few decades. At most places it has been welcomed as the next best thing to technology itself. Much of the intellectual talent from academic institutions is getting absorbed in lucrative positions in industry. Applied research finds willing collaborators in venture capital funded industry, so a symbiotic growth is ensured for both.
There are significant costs involved too. As academia interacts with industry, major areas of conflict of interest especially applicable to biomedical research have arisen. They are related to disputes over patents and royalty, hostile encounters between academia and industry, as also between public and private enterprise, legal tangles, research misconduct of various types, antagonistic press and patient-advocate lobbies and a general atmosphere in which commercial interest get precedence over patient welfare.
Pharma image stinks because of a number of errors of omission and commission. A recent example is suppression of negative findings about Bayer's Trasylol (Aprotinin) and the marketing maneuvers of Eli Lilly's Xigris (rhAPC). Whenever there is a conflict between patient vulnerability and profit motives, pharma often tends to tilt towards the latter. Moreover there are documents that bring to light how companies frequently cross the line between patient welfare and profit seeking behaviour.
A voluntary moratorium over pharma spending to pamper drug prescribers is necessary. A code of conduct adopted recently by OPPI in India to limit pharma company expenses over junkets and trinkets is a welcome step.
Clinical practice guidelines (CPG) are considered important as they guide the diagnostic/therapeutic regimen of a large number of medical professionals and hospitals and provide recommendations on drugs, their dosages and criteria for selection. Along with clinical trials, they are another area of growing influence by the pharmaceutical industry. For example, in a relatively recent survey of 2002, it was found that about 60% of 192 authors of clinical practice guidelines reported they had financial connections with the companies whose drugs were under consideration. There is a strong case for making CPGs based not just on effectivity but cost effectivity. The various ramifications of this need to be spelt out. Work of bodies like the Appraisal of Guidelines Research and Evaluation (AGREE) Collaboration and Guidelines Advisory Committee (GAC) are also worth a close look.
Even the actions of Foundations that work for disease amelioration have come under scrutiny. The process of setting up ‘Best Practices’ Guidelines for interactions between the pharmaceutical industry and clinicians has already begun and can have important consequences for patient care. Similarly, Good Publication Practice (GPP) for pharmaceutical companies have also been set up aimed at improving the behaviour of drug companies while reporting drug trials
The rapidly increasing trend toward influence and control by industry has become a concern for many. It is of such importance that the Association of American Medical Colleges has issued two relatively new documents - one, in 2001, on how to deal with individual conflicts of interest; and the other, in 2002, on how to deal with institutional conflicts of interest in the conduct of clinical research. Academic Medical Centers (AMCs), as also medical education and research institutions at other places, have to adopt means that minimize their conflicts of interest.
Both medical associations and research journal editors are getting concerned with individual and institutional conflicts of interest in the conduct of clinical research and documents are now available which address these issues. The 2001 ICMJE revision calls for full disclosure of the sponsor's role in research, as well as assurance that the investigators are independent of the sponsor, are fully accountable for the design and conduct of the trial, have independent access to all trial data and control all editorial and publication decisions. However the findings of a 2002 study suggest that academic institutions routinely participate in clinical research that does not adhere to ICMJE standards of accountability, access to data and control of publication.
There is an inevitable slant to produce not necessarily useful but marketable products which ensure the profitability of industry and research grants outflow to academia. Industry supports new, not traditional, therapies, irrespective of what is effective. Whatever traditional therapy is supported is most probably because the company concerned has a product with a big stake there, which has remained a ‘gold standard’ or which that player thinks has still some ‘juice’ left.
Industry sponsorship is mainly for potential medications, not for trying to determine whether there may be non-pharmacological interventions that may be equally good, if not better. In the paradigm shift towards biological psychiatry, the role of industry sponsorship is not overt but probably more pervasive than many have realised, or the right thinking may consider good, for the health of the branch in the long run.
An issue of major concern is protection of the interests of research subjects. Patients agree to become research subjects not only for personal medical benefit but, as an extension, to benefit the rest of the patient population and also advance medical research.
We all accept that industry profits have to be made, and investment in research and development by the pharma industry is massive. However, we must also accept there is a fundamental difference between marketing strategies for other entities and those for drugs.
The ultimate barometer is patient welfare and no drug that compromises it can stand the test of time. So, how does it make even commercial sense in the long term to market substandard products? The greatest mistake long-term players in industry may make is try to adopt the shady techniques of the upstart new entrant. Secrecy of marketing/sales tactics, of the process of manufacture, of other strategies and plans of business expansion, of strategies to tackle competition are fine business tactics. But it is critical that secrecy as a tactic not extend to reporting of research findings, especially those contrary to one's product.
Pharma has no option but to make a quality product, do comprehensive adverse reaction profiles, and market it only if it passes both tests.
Why does pharma adopt questionable tactics? The reasons are essentially two:
What with all the constraints, a drug comes to the pharmacy after huge investments. There are crippling overheads and infrastructure costs to be recovered. And there are massive profit margins to be maintained. If these were to be dependent only on genuine drug discoveries, that would be taking too great a risk.Industry players have to strike the right balance between profit making and credibility. In profit making, the marketing champions play their role. In credibility ratings, researchers and paid spokes-persons play their role. All is hunky dory till marketing is based on credibility. When there is nothing available to make for credibility, something is projected as one and marketing carried out, in the calculated hope that profits can accrue, since profit making must continue endlessly. That is what makes pharma adopt even questionable means to make profits.
Essentially, there are four types of drugs. First, drugs that work and have minimal side-effects; second, drugs which work but have serious side-effects; third, drugs that do not work and have minimal side-effects; and fourth, drugs which work minimally but have serious side-effects. It is the second and fourth types that create major hassles for industry. Often, industry may try to project the fourth type as the second to escape censure.
The major cat and mouse game being played by conscientious researchers is in exposing the third and fourth for what they are and not allowing industry to palm them off as the first and second type respectively. The other major game is in preventing the second type from being projected as the first. The third type are essentially harmless, so they attract censure all right and some merriment at the antics to market them. But they escape anything more than a light rap on the knuckles, except when they are projected as the first type.
What is necessary for industry captains and long-term players is to realise:
Their major propelling force can only be producing the first type. 2. They accept the second type only till they can lay their hands on the first. 3. The third type can be occasionally played around with to shore up profits, but never by projecting them as the first type. 4. The fourth type are the laggards, real threat to credibility and therefore do not deserve any market hype or promotion.
In finding out why most pharma indulges in questionable tactics, we are lead to some interesting solutions to prevent such tactics with the least amount of hassles for all concerned, even as both profits and credibility are kept intact.
doi:10.4103/0973-1229.32176
PMCID: PMC3192391  PMID: 22058616
Academia; Pharmaceutical Industry; Clinical Practice Guidelines; Best Practice Guidelines; Academic Medical Centers; Medical Associations; Research Journals; Clinical Research; Public Welfare; Pharma Image; Corporate Welfare; Biological Psychiatry; Law Suits Against Industry
9.  P01.02. Positive Psychology: A Path to Greater Well-being 
Focus Area: Supporting Behavioral Change
In 1998, when Dr Martin Seligman was president of the American Psychological Association, he proposed a new approach to psychology. The thinking at that time led to a disease-based model in which the focus was on treating mental illness. Dr Seligman advocated, however, that the science should be expanded to include factors that contribute to optimal functioning and greater well-being. He, along with his colleague Dr Csikszentmihalyi, stated, “The exclusive focus on pathology that has dominated so much of our discipline results in a model of the human being lacking the positive features that make life worth living.” Since this time, a more complete and balanced scientific understanding of the human experience has begun to unfold, with human flourishing being the goal. The five pillars that significantly contribute to a flourishing life and greater well-being include positive emotions, engagement, relationships, meaning, and accomplishment. It is important to incorporate these pillars into our professional and personal lives, but in doing so, we must keep in mind the fundamental building blocks to getting there: responsibility, choice, and action. Even as far back as the ancient Greek philosophers, it was believed that “the good life” is not something that happens to us—it is not something the world owes us. There is nothing passive about it. Now, with the scientific model that Positive Psychology has given us, we have a path to follow that will move us in the direction of this “good life.”
doi:10.7453/gahmj.2013.097CP.P01.02
PMCID: PMC3875005
10.  Self-Referenced Memory, Social Cognition, and Symptom Presentation in Autism 
Background
We examined performance on a self-referenced memory (SRM) task for higher functioning children with autism (HFA) and a matched comparison group. SRM performance was examined in relation to symptom severity and social cognitive tests of mentalizing.
Method
Sixty-two children (31 HFA, 31 comparison; 8–16 years) completed a SRM task in which they read a list of words and decided whether the word described something about them, something about Harry Potter, or contained a certain number of letters. They then identified words that were familiar from a longer list. Dependent measures were memory performance (d′) in each of the three encoding conditions as well as a self-memory bias score (d′ self-d′ other). Children completed The Strange Stories Task and The Children’s Eyes Test as measures of social cognition. Parents completed the SCQ and ASSQ as measures of symptom severity.
Results
Children in the comparison sample showed the standard SRM effect in which they recognized significantly more self-referenced words relative to words in the other-referenced and letter conditions. In contrast, HFA children showed comparable rates of recognition for self- and other-referenced words. For all children, SRM performance improved with age and enhanced SRM performance was related to lower levels of social problems. These associations were not accounted for by performance on the mentalizing tasks.
Conclusions
Children with HFA did not show the standard enhanced processing of self- vs. other-relevant information. Individual differences in the tendency to preferentially process self-relevant information may be associated with social cognitive processes that serve to modify the expression of social symptoms in children with autism.
doi:10.1111/j.1469-7610.2008.02059.x
PMCID: PMC2697280  PMID: 19298471
11.  Portrait of a Leader in Immunotherapeutics 
Human Vaccines & Immunotherapeutics  2012;8(8):1018-1021.
When I heard about the concept of immunotherapeutics, I immediately loved it. Everything I had learned about medicine, cancer biology, genetics and oncology indicated to me that this was a potent approach, and at the time, completely untapped. I figured that since we had been unable to cure most metastatic solid tumors, something completely different needed to be employed. Realistically, “magic bullets” are not easy to find and therefore something that can be combined with other therapies, for enhanced synergy without overlapping adverse events, would be appealing.
doi:10.4161/hv.21699
PMCID: PMC3551870  PMID: 22914447
adenovirus; cancer; gene therapy; immunotherapy; oncolytic virus
12.  Organ transplantation and meaning of life: the quest for self fulfilment 
Today, the frequency and the rate of success resulting from advances in medicine have made organ transplantations an everyday occurrence. Still, organ transplantations and donations modify the subjective experience of human beings as regards the image they have of themselves, of body, of life and of death. If the concern of the quality of life and the survival of the patients is a completely human phenomenon, the fact remains that the possibility of organ transplantation and its justification depend a great deal on the culture in which we live. The exploration of the philosophical tradition allows for a reconsideration of organ transplantation. If we listen to people who have experienced the decline of one of their organs and their own rebirth through the organ of someone else, we arrive at the conclusion that they went through an extreme experience in which nothing appeared as before. All those experiences intensify philosophical questionings on the meaning of life with respect to self fulfilment. The concept of nature as the experience of others can be an authentic source from which to nourish our thoughts about organ transplantation. However, and this is our hypothesis, we need something more if we are to decide something about our own life. We need a hermeneutical stance in relation to ourselves and to our world. Philosophical counselling, as a long established tradition originating with Pythagoras and later reframed by the German philosopher Achenbach could be useful in inspiring a reflection on the good life, chiefly as it takes the form of a Socratic dialogue.
doi:10.1007/s11019-012-9439-z
PMCID: PMC3696169  PMID: 23014955
Nature; Naturalism; Phenomenology; Hermeneutics; Aristotle; Descartes; Meaning; Wisdom; Organ transplantation
13.  Effect of different forms of information produced for cancer patients on their use of the information, social support, and anxiety: randomised trial 
BMJ : British Medical Journal  2006;332(7547):942-948.
Objective To explore the hypothesis that different methods of selecting and printing information for cancer patients could improve emotional support by affecting interaction with others, and so lead to improved psychological wellbeing.
Design Randomised trial with eight groups (three factors, 2×2×2). Data collected at recruitment and three month follow-up.
Participants 400 patients starting radiotherapy, of whom 325 with breast or prostate cancer and complete anxiety and depression data were included in the analysis.
Interventions Printed booklets: half had only general information from CancerBACUP about each patient's cancer and half had personalised information from the patient's medical record plus selected general information; half were composed of information chosen interactively by the patient and half were produced automatically with a larger volume of material; and half had additional advice on anxiety management and half did not.
Main outcome measures Patients' views of the information, use of their booklets with others; change in reported social support; change in anxiety and depression.
Results The larger booklets produced automatically were more likely to be found useful and to tell patients something new and less likely to be seen as too limited than the booklets produced interactively, but they were also more likely to overwhelm some patients. Personalised booklets were more likely than general booklets to tell patients something new. There was no difference in patients' perceived understanding of their cancer by any of the intervention factors. Patients with personalised information were more likely to show their booklets to others and to think it helped in discussing their cancer or its treatment. There were no major differences in social support, anxiety, or depression by any intervention factors.
Conclusions Patients were more likely to show personalised information to their confidants than general information. Further research is needed into the effects of sharing information on patients' social support and anxiety.
Trial registration US Government Clinical Trials Database NCT00127465
doi:10.1136/bmj.38807.571042.68
PMCID: PMC1444811  PMID: 16597660
14.  The role of personal purpose and personal goals in symbiotic visions 
It is believed that symbiotic visions can drive employees and organizations toward a common objective based on the premise that people have a high level of self-motivation and engagement when they are working toward something very personal. The field of organizational development has been aspiring to help organizations and people align their visions for decades without much, if any, empirical support for the role of personal purpose and goals in the symbiotic relationship with a company vision. This qualitative study examines the role personal purpose and goals play in how high performing leaders align to their company's vision. Whether and how senior managers articulate this alignment, and its correlation to their motivation and engagement, was examined. An observation was that most senior managers within organizations with a well-developed and widely known higher purpose vision are driven by something personal, identified as either personal goals or a personal purpose. One of the key findings is that personal purpose and goals, when aligned to a company vision, appear to impact motivation and engagement in different ways. When alignment is felt through the sense of the greater purpose, there is a deep, almost spiritual, commitment to making the world a better place and helping the organization contribute to that. This seems to motivate them to guide the organization toward its higher purpose vision. When alignment is felt through the organization's alignment to one's personal goals, there is a great sense of commitment to completing the steps or tasks necessary to move toward the vision, yet a clear delineation between work and life ambitions.
doi:10.3389/fpsyg.2015.00443
PMCID: PMC4396129  PMID: 25926808
higher purpose; calling; meaning; vision; shared vision; motivation; engagement; relationships
15.  An international internet survey of the experiences of 1,714 mothers with a late stillbirth: the STARS cohort study 
Background
Stillbirth occurring after 28 weeks gestation affects between 1.5–4.5 per 1,000 births in high-income countries. The majority of stillbirths in this setting occur in women without risk factors. In addition, many established risk factors such as nulliparity and maternal age are not amenable to modification during pregnancy. Identification of other risk factors which could be amenable to change in pregnancy should be a priority in stillbirth prevention research. Therefore, this study aimed to utilise an online survey asking women who had a stillbirth about their pregnancy in order to identify any common symptoms and experiences.
Methods
A web-based survey.
Results
A total of 1,714 women who had experienced a stillbirth >3 weeks prior to enrolment completed the survey. Common experiences identified were: perception of changes in fetal movement (63 % of respondents), reports of a “gut instinct” that something was wrong (68 %), and perceived time of death occurring overnight (56 %). A quarter of participants believed that their baby’s death was due to a cord issue and another 18 % indicated that they did not know the reason why their baby died. In many cases (55 %) the mother believed the cause of death was different to that told by clinicians.
Conclusions
This study confirms the association between altered fetal movements and stillbirth and highlights novel associations that merit closer scrutiny including a maternal gut instinct that something was wrong. The potential importance of maternal sleep is highlighted by the finding of more than half the mothers believing their baby died during the night. This study supports the importance of listening to mothers’ concerns and symptoms during pregnancy and highlights the need for thorough investigation of stillbirth and appropriate explanation being given to parents.
Electronic supplementary material
The online version of this article (doi:10.1186/s12884-015-0602-4) contains supplementary material, which is available to authorized users.
doi:10.1186/s12884-015-0602-4
PMCID: PMC4537542  PMID: 26276347
16.  United States Private-Sector Physicians and Pharmaceutical Contract Research: A Qualitative Study 
PLoS Medicine  2012;9(7):e1001271.
Jill Fisher and Corey Kalbaugh describe their findings from a qualitative research study evaluating the motivations of private-sector physicians conducting contract research for the pharmaceutical industry.
Background
There have been dramatic increases over the past 20 years in the number of nonacademic, private-sector physicians who serve as principal investigators on US clinical trials sponsored by the pharmaceutical industry. However, there has been little research on the implications of these investigators' role in clinical investigation. Our objective was to study private-sector clinics involved in US pharmaceutical clinical trials to understand the contract research arrangements supporting drug development, and specifically how private-sector physicians engaged in contract research describe their professional identities.
Methods and Findings
We conducted a qualitative study in 2003–2004 combining observation at 25 private-sector research organizations in the southwestern United States and 63 semi-structured interviews with physicians, research staff, and research participants at those clinics. We used grounded theory to analyze and interpret our data. The 11 private-sector physicians who participated in our study reported becoming principal investigators on industry clinical trials primarily because contract research provides an additional revenue stream. The physicians reported that they saw themselves as trial practitioners and as businesspeople rather than as scientists or researchers.
Conclusions
Our findings suggest that in addition to having financial motivation to participate in contract research, these US private-sector physicians have a professional identity aligned with an industry-based approach to research ethics. The generalizability of these findings and whether they have changed in the intervening years should be addressed in future studies.
Please see later in the article for the Editors' Summary.
Editors' Summary
Background
Before a new drug can be used routinely by physicians, it must be investigated in clinical trials—studies that test the drug's safety and effectiveness in people. In the past, clinical trials were usually undertaken in academic medical centers (institutes where physicians provide clinical care, do research, and teach), but increasingly, clinical trials are being conducted in the private sector as part of a growing contract research system. In the US, for example, most clinical trials completed in the 1980s took place in academic medical centers, but nowadays, more than 70% of trials are conducted by nonacademic (community) physicians working under contract to pharmaceutical companies. The number of private-sector nonacademic physicians serving as principal investigators (PIs) for US clinical trials (the PI takes direct responsibility for completion of the trial) increased from 4,000 in 1990 to 20,250 in 2010, and research contracts for clinical trials are now worth more than USṩ11 billion annually.
Why Was This Study Done?
To date, there has been little research on the implications of this change in the conduct of clinical trials. Academic PIs are often involved in both laboratory and clinical research and are therefore likely to identify closely with the science of trials. By contrast, nonacademic PIs may see clinical trials more as a business opportunity—pharmaceutical contract research is profitable to US physicians because they get paid for every step of the trial process. As a result, pharmaceutical companies may now have more control over clinical trial data and more opportunities to suppress negative data through selective publication of study results than previously. In this qualitative study, the researchers explore the outsourcing of clinical trials to private-sector research clinics through observations of, and in-depth interviews with, physicians and other research staff involved in the US clinical trials industry. A qualitative study collects non-quantitative data such as how physicians feel about doing contract research and about their responsibilities to their patients.
What Did the Researchers Do and Find?
Between October 2003 and September 2004, the researchers observed the interactions between PIs, trial coordinators (individuals who undertake many of the trial activities such as blood collection), and trial participants at 25 US research organizations in the southwestern US and interviewed 63 informants (including 12 PIs) about the trials they were involved in and their reasons for becoming involved. The researchers found that private-sector physicians became PIs on industry-sponsored clinical trials primarily because contract research was financially lucrative. The physicians perceived their roles in terms of business rather than science and claimed that they offered something to the pharmaceutical industry that academics do not—the ability to carry out a diverse range of trials quickly and effectively, regardless of their medical specialty. Finally, the physicians saw their primary ethical responsibility as providing accurate data to the companies that hired them and did not explicitly refer to their ethical responsibility to trial participants. One possible reason for this shift in ethical concerns is the belief among private-sector physicians that pharmaceutical companies must be making scientifically and ethically sound decisions when designing trials because of the amount of money they invest in them.
What Do These Findings Mean?
These findings suggest that private-sector physicians participate as PIs in pharmaceutical clinical trials primarily for financial reasons and see themselves as trial practitioners and businesspeople rather than as scientists. The accuracy of these findings is likely to be limited by the small number of PIs interviewed and by the time that has elapsed since the researchers collected their qualitative data. Moreover, these findings may not be generalizable to other regions of the US or to other countries. Nevertheless, they have potentially troubling implications for drug development. By hiring private-sector physicians who see themselves as involved more with the business than the science of contract research, pharmaceutical companies may be able to exert more control over the conduct of clinical trials and the publication of trial results than previously. Compared to the traditional investigatorinitiated system of clinical research, this new system of contract research means that clinical trials now lack the independence that is at the heart of best science practices, a development that casts doubt on the robustness of the knowledge being produced about the safety and effectiveness of new drugs.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001271.
The ClinicalTrials.gov website is a searchable register of federally and privately supported clinical trials in the US; it provides information about all aspects of clinical trials
The US National Institutes of Health provides information about clinical trials, including personal stories about clinical trials from patients and researchers
The UK National Health Service Choices website has information for patients about clinical trials and medical research, including personal stories about participating in clinical trials
The UK Medical Research Council Clinical Trials Unit also provides information for patients about clinical trials and links to information on clinical trials provided by other organizations
MedlinePlus has links to further resources on clinical trials (in English and Spanish)
doi:10.1371/journal.pmed.1001271
PMCID: PMC3404112  PMID: 22911055
17.  PHL8/445: Internet Courses for Cancer Patients 
In September 1998 INKA started the first practical courses on the internet for cancer patients and their families in Germany. The aim was to show how they can use the internet to take more active control over the healing process. The project was open to all cancer patients and situated at the VHS Hamburg West (public adult education institute). Thanks to our sponsor the course fee was subsidised.85 participants took part. Most of them were cancer patients, with varying types of cancer. 2/3 were female and attended the course together with a family member or friend. They were aged 25-76 years and some of them even travelled from afar. 1/2 of the patients had a poor prognosis and a rare type of cancer. Asked why they took part they answered that they were either just curious, could not accept their poor prognosis, wanted to do something actively, thought INKA was a great project they wanted to join or were sent by their doctors to find out more information. Most of them were complete beginners with no internet experience, some without any computer knowledge. Apart from the technical introduction into the internet, its terms, retrieval methods etc. the participants had also enough opportunities for personal exchange within the group. Some keep in contact with each other and the project even now and 1/3 have their own internet access in the meantime. The patients and their families said that they were mostly dissatisfied with their interaction with their doctors and felt that the course was personally beneficial. The internet opened up a new dimension for them in the communication process, in that they learned that there is more and better information which they can print out and show to their doctors. They also liked to interact with experienced cancer survivors in the net. In general the course helped them to feel secure in their own healing decisions. Patients and institutions from all over Germany, Swiss and Austria showed interest and the conclusion is simple: there is a huge demand for this type of service. The project received a lot of press attention so that there were many multipliers in the health sector who now ask us for education material on this subject which INKA willing to provide in the future.
doi:10.2196/jmir.1.suppl1.e89
PMCID: PMC1761803
Cancer; Courses; Education; Patients; Public Adult Education
18.  Why bodies? Twelve reasons for including bodily expressions in affective neuroscience 
Why bodies? It is rather puzzling that given the massive interest in affective neuroscience in the last decade, it still seems to make sense to raise the question ‘Why bodies’ and to try to provide an answer to it, as is the goal of this article. There are now hundreds of articles on human emotion perception ranging from behavioural studies to brain imaging experiments. These experimental studies complement decades of reports on affective disorders in neurological patients and clinical studies of psychiatric populations. The most cursory glance at the literature on emotion in humans, now referred to by the umbrella term of social and affective neuroscience, shows that over 95 per cent of them have used faces as stimuli. Of the remaining 5 per cent, a few have used scenes or auditory information including human voices, music or environmental sounds. But by far the smallest number has looked into whole-body expressions. As a rough estimate, a search on PubMed today, 1 May 2009, yields 3521 hits for emotion × faces, 1003 hits for emotion × music and 339 hits for emotion × bodies. When looking in more detail, the body × emotion category in fact yields a majority of papers on well-being, nursing, sexual violence or organ donation. But the number of cognitive and affective neuroscience studies of emotional body perception as of today is lower than 20.
Why then have whole bodies and bodily expressions not attracted the attention of researchers so far? The goal of this article is to contribute some elements for an answer to this question. I believe that there is something to learn from the historical neglect of bodies and bodily expressions. I will next address some historical misconceptions about whole-body perception, and in the process I intend not only to provide an impetus for this kind of work but also to contribute to a better understanding of the significance of the affective dimension of behaviour, mind and brain as seen from the vantage point of bodily communication. Subsequent sections discuss available evidence for the neurofunctional basis of facial and bodily expressions as well as neuropsychological and clinical studies of bodily expressions.
doi:10.1098/rstb.2009.0190
PMCID: PMC2781896  PMID: 19884142
19.  Divergent kleisin subunits of cohesin specify mechanisms to tether and release meiotic chromosomes 
eLife  2014;3:e03467.
We show that multiple, functionally specialized cohesin complexes mediate the establishment and two-step release of sister chromatid cohesion that underlies the production of haploid gametes. In C. elegans, the kleisin subunits REC-8 and COH-3/4 differ between meiotic cohesins and endow them with distinctive properties that specify how cohesins load onto chromosomes and then trigger and release cohesion. Unlike REC-8 cohesin, COH-3/4 cohesin becomes cohesive through a replication-independent mechanism initiated by the DNA double-stranded breaks that induce crossover recombination. Thus, break-induced cohesion also tethers replicated meiotic chromosomes. Later, recombination stimulates separase-independent removal of REC-8 and COH-3/4 cohesins from reciprocal chromosomal territories flanking the crossover site. This region-specific removal likely underlies the two-step separation of homologs and sisters. Unexpectedly, COH-3/4 performs cohesion-independent functions in synaptonemal complex assembly. This new model for cohesin function diverges from that established in yeast but likely applies directly to plants and mammals, which utilize similar meiotic kleisins.
DOI: http://dx.doi.org/10.7554/eLife.03467.001
eLife digest
Most plant and animal cells have a pair of each chromosome: one copy is inherited from the father, the other from the mother. When a cell divides, each daughter cell must receive a copy of all of the original cell's genetic information. To this end, the chromosomes are replicated to form so-called ‘sister chromatids’, which are then segregated equally between the two daughter cells.
In contrast, sex cells such as eggs and sperm (also called gametes) have a single copy of each chromosome. When an egg and a sperm fuse to form a single cell (called a zygote), the zygote ends up with a full set of chromosomes. Gametes are formed by two successive rounds of cell division that occur after the chromosomes are replicated. The first round separates the pairs of chromosomes, and the second separates the sister chromatids to produce the gametes, each of which has half the original amount of genetic information.
If something goes awry in the production of gametes, a zygote can end up with the wrong number of chromosomes. Almost one-third of human zygotes inherit an aberrant complement of chromosomes, and many of these zygotes either fail to survive or develop into offspring with birth defects and developmental disorders.
To ensure that gametes receive the correct number of chromosomes, the sister chromatids remain bound together by a ring-shaped protein complex during the first cell division. Previous studies on how this protein complex—called cohesin—tethers the sister chromatids together were conducted on yeast and mammalian cells. Now, Severson and Meyer show that, in a microscopic worm called Caenorhabditis elegans, cohesin functions differently from how it functions in the simpler yeast cells.
Severson and Meyer found that rather than using a single cohesin complex like in yeast, the worms use multiple cohesin complexes that have different versions of one key protein subunit. Changing this single subunit has a major impact on cohesin's function. Consequently, each complex plays a specific role in tethering and then releasing sister chromatids. One of the cohesin complexes is triggered to tether the sister chromatids when the chromosomes replicate. Unexpectedly, another complex only tethers the sisters once breaks occur in the DNA. These breaks allow sister chromatids that are produced from maternally- and paternally-derived chromosomes to cross over and swap genetic material—which increases the genetic diversity of any future offspring. After these genetic swaps occur, the cohesin complexes are then selectively removed by different mechanisms, first to release the pairs of chromosomes and then the sister chromatids.
The findings of Severson and Meyer establish a new model for the mechanisms of chromosome segregation during gamete production. Further studies are now needed to determine the roles and regulation of these protein complexes in other species—including plants and mammals, which use similar cohesin complexes.
DOI: http://dx.doi.org/10.7554/eLife.03467.002
doi:10.7554/eLife.03467
PMCID: PMC4174578  PMID: 25171895
cohesin; sister chromatid cohesion; meiosis; gametogenesis; kleisin; aneuploidy; C. elegans
20.  Preconceptional Folate Supplementation and the Risk of Spontaneous Preterm Birth: A Cohort Study 
PLoS Medicine  2009;6(5):e1000061.
In an analysis of a cohort of pregnant women, Radek Bukowski and colleagues describe an association between taking folic acid supplements and a reduction in the risk of preterm birth.
Background
Low plasma folate concentrations in pregnancy are associated with preterm birth. Here we show an association between preconceptional folate supplementation and the risk of spontaneous preterm birth.
Methods and Findings
In a cohort of 34,480 low-risk singleton pregnancies enrolled in a study of aneuploidy risk, preconceptional folate supplementation was prospectively recorded in the first trimester of pregnancy. Duration of pregnancy was estimated based on first trimester ultrasound examination. Natural length of pregnancy was defined as gestational age at delivery in pregnancies with no medical or obstetrical complications that may have constituted an indication for delivery. Spontaneous preterm birth was defined as duration of pregnancy between 20 and 37 wk without those complications. The association between preconceptional folate supplementation and the risk of spontaneous preterm birth was evaluated using survival analysis. Comparing to no supplementation, preconceptional folate supplementation for 1 y or longer was associated with a 70% decrease in the risk of spontaneous preterm delivery between 20 and 28 wk (41 [0.27%] versus 4 [0.04%] spontaneous preterm births, respectively; HR 0.22, 95% confidence interval [CI] 0.08–0.61, p = 0.004) and a 50% decrease in the risk of spontaneous preterm delivery between 28 and 32 wk (58 [0.38%] versus 12 [0.18%] preterm birth, respectively; HR 0.45, 95% CI 0.24–0.83, p = 0.010). Adjustment for maternal characteristics age, race, body mass index, education, marital status, smoking, parity, and history of prior preterm birth did not have a material effect on the association between folate supplementation for 1 y or longer and spontaneous preterm birth between 20 and 28, and 28 to 32 wk (adjusted HR 0.31, 95% CI 0.11–0.90, p = 0.031 and 0.53, 0.28–0.99, p = 0.046, respectively). Preconceptional folate supplementation was not significantly associated with the risk of spontaneous preterm birth beyond 32 wk. The association between shorter duration (<1 y) of preconceptional folate supplementation and the risk of spontaneous preterm birth was not significant after adjustment for maternal characteristics. However, the risk of spontaneous preterm birth decreased with the duration of preconceptional folate supplementation (test for trend of survivor functions, p = 0.01) and was the lowest in women who used folate supplementation for 1 y or longer. There was also no significant association with other complications of pregnancy studied after adjustment for maternal characteristics.
Conclusions
Preconceptional folate supplementation is associated with a 50%–70% reduction in the incidence of early spontaneous preterm birth. The risk of early spontaneous preterm birth is inversely proportional to the duration of preconceptional folate supplementation. Preconceptional folate supplementation was specifically related to early spontaneous preterm birth and not associated with other complications of pregnancy.
Editors' Summary
Background
Most pregnancies last about 40 weeks, but sometimes the new family member arrives early. Every year, half a million babies in the United States (12.5% of all babies) are born prematurely (before 37 completed weeks of pregnancy). Sadly, premature babies are more likely to die than full-term babies and many have short- and/or long-term health problems. Premature babies often have breathing problems, they are susceptible to life-threatening infections, and they are more likely to have learning and developmental disabilities than those born on time. The severity of these health problems depends on the degree of prematurity—preterm babies born between 34 and 36 weeks of pregnancy rarely develop severe disabilities, but a quarter of babies born before 28 weeks of pregnancy develop serious lasting disabilities and half have learning and behavioral problems. Although doctors have identified some risk factors for early delivery (for example, smoking), it is impossible to predict who will have an early birth and there is no effective way to prevent preterm births.
Why Was This Study Done?
Some researchers think that folate supplements may prevent preterm births. Folate (folic acid), a vitamin found in leafy green vegetables, fruits, and dried beans, helps to prevent neural tube birth defects. Consequently, women are encouraged to take folic acid supplements throughout (and preferably before) pregnancy and many governments now mandate that bread, pasta, and other grain products be fortified with folic acid to help women get sufficient folate. There is some evidence that women who deliver early have less folate in their blood than women who deliver at term. Furthermore, folate supplementation during pregnancy has increased the length of pregnancy in some but not all clinical trials. A possible explanation for these mixed results is that the duration of pregnancy reflects conditions in the earliest stages of pregnancy or before conception and that folate supplementation needs to start before conception to reduce the risk of preterm birth. In this study, the researchers test this idea by analyzing data collected from nearly 35,000 pregnant women enrolled in a study that was originally designed to investigate screening for Down's syndrome.
What Did the Researchers Do and Find?
During the first three months of their pregnancy, the women were asked whether they had taken folate supplements before conception. The duration of each pregnancy was estimated from ultrasound measurements taken early in the pregnancy and from the time of delivery. During the study, 1,658 women had spontaneous preterm deliveries before 37 weeks and 160 delivered before 32 weeks. After allowing for other maternal characteristics that might have affected the likelihood of preterm delivery, the risk of spontaneous preterm delivery between 20 and 28 weeks was 70% lower in women who took folate supplements for more than a year before becoming pregnant than in women who didn't take a supplement. Long-term folate supplementation also reduced the risk of preterm delivery between 28 and 32 weeks by 50% but did not affect the risk of preterm birth beyond 32 weeks. Folate supplementation for less than a year before conception did not reduce the risk of preterm birth, and folate supplementation was not associated with any other complications of pregnancy.
What Do These Findings Mean?
These findings show that folate supplementation for a year or more before conception is associated with a 50%–70% decrease in early (but not late) spontaneous preterm births and that the longer a woman takes folate supplements before becoming pregnant, the lower her risk of a preterm birth. Although the researchers allowed for maternal characteristics that might have affected the duration of pregnancy, it is possible that folate supplementation may not be responsible for the reduction in preterm birth risk seen in this study. For example, taking folate supplements may be a marker of healthy behavior and the women taking the supplements might have been doing something else that was reducing their risk of preterm birth. However, despite this and other limitations of this study, these findings suggest that long-term folate supplementation before conception is worth investigating further as a potential way to prevent preterm births.
Additional Information
Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000061.
This study is further discussed in a PLoS Medicine Perspective by Nicholas Fisk
The MedlinePlus encyclopedia contains a page on premature babies (in English and Spanish); MedlinePlus provides links to other information on premature babies (in English and Spanish)
The US National Institute of Child Health and Human Development provides information on preterm labor and birth
The March of Dimes, a nonprofit organization for pregnancy and baby health, provides information on preterm birth and on folic acid (in English and Spanish)
The Nemours Foundation, another nonprofit organization for child health, also provides information on premature babies (in English and Spanish)
The US Office of Dietary Supplements has a fact sheet on folate
doi:10.1371/journal.pmed.1000061
PMCID: PMC2671168  PMID: 19434228
21.  Structural rigidity of a large cavity-containing protein revealed by high-pressure crystallography 
Journal of molecular biology  2006;367(3):752-763.
Steric constraints, charged interactions and many other forces important to protein structure and function can be explored by mutagenic experiments. Research of this kind has led to a wealth of knowledge about what stabilizes proteins in their folded states. To gain a more complete picture requires that we perturb these structures in a continuous manner, something mutagenesis cannot achieve. With high pressure crystallographic methods it is now possible to explore the detailed properties of proteins while continuously varying thermodynamic parameters. In this paper, we detail the structural response of the cavity-containing mutant L99A of T4 lysozyme, as well as its pseudo wild-type (WT*) counterpart, to hydrostatic pressure. Surprisingly, the cavity has almost no effect on the pressure response: virtually the same changes are observed in WT* as in L99A under pressure. The cavity is most rigid, while other regions deform substantially. This implies that while some residues may increase the thermodynamic stability of a protein, they may also be structurally irrelevant. As recently shown, the cavity fills with water at pressures above 100 MPa while retaining its overall size. The resultant picture of the protein is one in which conformationally fluctuating side groups provide a liquid-like environment, but which also contribute to the rigidity of the peptide backbone.
doi:10.1016/j.jmb.2006.12.021
PMCID: PMC1853337  PMID: 17292912
22.  Auditory selective attention is enhanced by a task-irrelevant temporally coherent visual stimulus in human listeners 
eLife  null;4:e04995.
In noisy settings, listening is aided by correlated dynamic visual cues gleaned from a talker's face—an improvement often attributed to visually reinforced linguistic information. In this study, we aimed to test the effect of audio–visual temporal coherence alone on selective listening, free of linguistic confounds. We presented listeners with competing auditory streams whose amplitude varied independently and a visual stimulus with varying radius, while manipulating the cross-modal temporal relationships. Performance improved when the auditory target's timecourse matched that of the visual stimulus. The fact that the coherence was between task-irrelevant stimulus features suggests that the observed improvement stemmed from the integration of auditory and visual streams into cross-modal objects, enabling listeners to better attend the target. These findings suggest that in everyday conditions, where listeners can often see the source of a sound, temporal cues provided by vision can help listeners to select one sound source from a mixture.
DOI: http://dx.doi.org/10.7554/eLife.04995.001
eLife digest
In the noisy din of a cocktail party, there are many sources of sound that compete for our attention. Even so, we can easily block out the noise and focus on a conversation, especially when we are talking to someone in front of us.
This is possible in part because our sensory system combines inputs from our senses. Scientists have proposed that our perception is stronger when we can hear and see something at the same time, as opposed to just being able to hear it. For example, if we tried to talk to someone on a phone during a cocktail party, the background noise would probably drown out the conversation. However, when we can see the person we are talking to, it is easier to hold a conversation.
Maddox et al. have now explored this phenomenon in experiments that involved human subjects listening to an audio stream that was masked by background sound. While listening, the subjects also watched completely irrelevant videos that moved in sync with either the audio stream or with the background sound. The subjects then had to perform a task that involved pushing a button when they heard random changes (such as subtle changes in tone or pitch) in the audio stream.
The experiment showed that the subjects performed well when they saw a video that was in sync with the audio stream. However, their performance dropped when the video was in sync with the background sound. This suggests that when we hold a conversation during a noisy cocktail party, seeing the other person's face move as they talk creates a combined audio–visual impression of that person, helping us separate what they are saying from all the noise in the background. However, if we turn to look at other guests, we become distracted and the conversation may become lost.
DOI: http://dx.doi.org/10.7554/eLife.04995.002
doi:10.7554/eLife.04995
PMCID: PMC4337603  PMID: 25654748
auditory-visual integration; auditory scene analysis; multisensory; selective attention; temporal coherence; human
23.  What are health authorities doing about the health problems caused by unemployment? 
Unemployment is over three million in Britain, and unemployment is known to be associated with poor health. It has been suggested that health authorities should produce a comprehensive response to the health problems caused by unemployment, and a survey was undertaken to find how many had done so. All the regional and district health authorities in England, the health boards of Wales, Scotland, and Northern Ireland, and the family practitioner committees of England and Wales were asked by letter what they were doing to respond to the health problems of unemployment. A list of suggestions of what they might be doing was enclosed. The overall response rate was 77% (255/331), and 50% (127/255) of the respondents were doing something--33.3% (3/9) of the regional health authorities, 64% (101/158) of the district health authorities and health boards, and 26% (23/88) of the family practitioner committees. The paper describes what they were doing. A relation was sought between the level of unemployment in an area and the extent of the response, and a significant association was found. Half of Britain's health authorities are now responding in some way to the health problems associated with unemployment.
Images
PMCID: PMC1246228  PMID: 3580820
24.  Structural basis for the prion-like MAVS filaments in antiviral innate immunity 
eLife  2014;3:e01489.
Mitochondrial antiviral signaling (MAVS) protein is required for innate immune responses against RNA viruses. In virus-infected cells MAVS forms prion-like aggregates to activate antiviral signaling cascades, but the underlying structural mechanism is unknown. Here we report cryo-electron microscopic structures of the helical filaments formed by both the N-terminal caspase activation and recruitment domain (CARD) of MAVS and a truncated MAVS lacking part of the proline-rich region and the C-terminal transmembrane domain. Both structures are left-handed three-stranded helical filaments, revealing specific interfaces between individual CARD subunits that are dictated by electrostatic interactions between neighboring strands and hydrophobic interactions within each strand. Point mutations at multiple locations of these two interfaces impaired filament formation and antiviral signaling. Super-resolution imaging of virus-infected cells revealed rod-shaped MAVS clusters on mitochondria. These results elucidate the structural mechanism of MAVS polymerization, and explain how an α-helical domain uses distinct chemical interactions to form self-perpetuating filaments.
DOI: http://dx.doi.org/10.7554/eLife.01489.001
eLife digest
When infected by a virus, the body will generally launch an immune response to eliminate the infectious agent. Activation of the innate immune system–the first line of defense against infection—requires the host cells to recognize the presence of a pathogen and to sound the alarm once the invader is detected.
Viruses can contain DNA or RNA, and when a virus containing double stranded RNA enters a cell, or starts replicating within the cytoplasm, proteins called RIG-I-like receptors (RLRs) will detect these RNA molecules. This will trigger a signaling cascade that results in the production of type I interferons, the proteins that activate cells of the innate immune system.
Members of the RLR family of receptors, including RIG-I and MDA5, initiate the signaling cascade by interacting with the mitochondrial antiviral-signaling (MAVS) protein. Recent work revealed that upon activation by RIG-I or MDA5, MAVS proteins aggregate on the surface of mitochondria and form protein filaments. These filaments then activate inactive MAVS proteins, leading to the formation of more filaments. While a region of the MAVS protein called caspase activation and recruitment domain (CARD) is known to be involved in the formation of the filaments, the chemical interactions that govern the formation process have yet to be described.
Now, using cryo-electron microscopy, Xu et al. have shown that these filaments are comprised of three-stranded helixes. This came as something of a surprise because other similar filaments known as prions are made of tightly packed beta sheets. Xu et al. went on to visualize full-length MAVS filaments in virus-infected cells, and to verify that mutations that impair the assembly of MAVS filaments also prevent RNA viruses from triggering the production of interferon. These results have the potential to inform future studies of the innate immune response, as well as investigations into the assembly of proteins to form prion-like filaments.
DOI: http://dx.doi.org/10.7554/eLife.01489.002
doi:10.7554/eLife.01489
PMCID: PMC3932521  PMID: 24569476
MAVS; innate immunity; prion-like filaments; cryoEM reconstruction; three-stranded filaments; human; viruses
25.  Frequency-selective control of cortical and subcortical networks by central thalamus 
eLife  null;4:e09215.
Central thalamus plays a critical role in forebrain arousal and organized behavior. However, network-level mechanisms that link its activity to brain state remain enigmatic. Here, we combined optogenetics, fMRI, electrophysiology, and video-EEG monitoring to characterize the central thalamus-driven global brain networks responsible for switching brain state. 40 and 100 Hz stimulations of central thalamus caused widespread activation of forebrain, including frontal cortex, sensorimotor cortex, and striatum, and transitioned the brain to a state of arousal in asleep rats. In contrast, 10 Hz stimulation evoked significantly less activation of forebrain, inhibition of sensory cortex, and behavioral arrest. To investigate possible mechanisms underlying the frequency-dependent cortical inhibition, we performed recordings in zona incerta, where 10, but not 40, Hz stimulation evoked spindle-like oscillations. Importantly, suppressing incertal activity during 10 Hz central thalamus stimulation reduced the evoked cortical inhibition. These findings identify key brain-wide dynamics underlying central thalamus arousal regulation.
DOI: http://dx.doi.org/10.7554/eLife.09215.001
eLife digest
The ability to wake up every morning and to fall asleep at night is something that most people take for granted. However, damage to a brain region called the central thalamus can cause a range of consciousness-related disorders, including memory problems, excessive sleeping, and even comas. For example, cell death within the central thalamus has been associated with severely disabled patients following traumatic brain injury.
Previous studies have found that electrically stimulating the neurons in the central thalamus can change whether an animal is drowsy or awake and alert. However, it was not clear whether a single group of neurons in the central thalamus was responsible for switching the brain’s state between sleep and wakefulness, or how this would work.
Liu, Lee, Weitz, Fang et al. have now used a technique called optogenetics to stimulate specific neurons in the central thalamus of rats, by using flashes of light. Stimulation was combined with several techniques to monitor the response of other brain regions, including fMRI imaging that shows the activity of the entire brain.
The results showed that rapidly stimulating the neurons in the central thalamus – 40 or 100 times a second – led to widespread brain activity and caused sleeping rats to wake up. In contrast, stimulating the neurons of the central thalamus more slowly – around 10 times a second – suppressed the activity of part of the brain called the sensory cortex and caused rats to enter a seizure-like state of unconsciousness. Further investigation identified a group of inhibitory neurons that the central thalamus interacts with to carry out this suppression.
The results suggest that the central thalamus can either power the brain to an “awake” state or promote a state of unconsciousness, depending on how rapidly its neurons are stimulated. Future work will seek to translate these results to the clinic and investigate how stimulation of the central thalamus can be optimized to reduce cognitive deficits in animal models of traumatic brain injury.
DOI: http://dx.doi.org/10.7554/eLife.09215.002
doi:10.7554/eLife.09215
PMCID: PMC4721962  PMID: 26652162
Central thalamus; Functional MRI; Optogenetics; Arousal; Rat

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