A number of researchers have proposed adding an increasing number of subthreshold variants of Major Depressive Disorder (MDD) as new mood disorders. However, this research has suffered from a number of theoretical and methodological flaws which the current investigation has attempted to address. Individuals with MDD (n = 470) were compared to individuals with subthreshold MDD (n = 57). Individuals suffering from MDD reported consistently more severe symptoms, albeit of small magnitude, as well as differences in comorbidity with only two disorders. Results also indicated that diagnosis did not significantly predict rate of symptom change when MDD was compared with its subthreshold variant. Taken together, the aforementioned evidence suggests that small differences exist between MDD and its subthreshold variant. In addition, the extent to which the latter serve as useful analogs for the former may depend upon the variables under study.
Depression; Diagnostic Assessment; Minor Depressive Disorder; Major Depressive Disorder; Dysthymia
An approach which promotes a rapid return to spontaneous respiration after tracheobronchial stent (TBS) insertion is considered the optimal one and is a belief shared by anaesthetists, respiratory physicians, and surgeons alike (Calvey and William (2008)). The value of the laryngeal mask airway (LMA), followed by use of the Monsoon 111 Acutronic jet ventilator pressure limiting system of ventilation, for the deployment of stents in the three individual cases that of tracheoesophageal fistula, a bronchoesophageal fistula, and tracheal compression from an invading oesophageal malignant tumour are reported. The roles of target controlled anaesthesia, high-frequency jet ventilation (HFJV), and the laryngeal mask airway in optimising the surgical field and reducing the risk of bronchospasm at emergence are advantages of this technique.
The Global Vascular Risk Management (GVRM) Study is a 5-year prospective observational study of 87,863 patients (61% females) with hypertension and associated cardiovascular risk factors began January 1, 2010. Data are gathered electronically and cardiovascular risk is evaluated using the Consortium for Southeastern Hypertension Control™ (COSEHC™)-11 risk score. Here, we report the results obtained at the completion of 33 months since study initiation. De-identified electronic medical records of enrolled patients were used to compare clinical indicators, antihypertensive medication usage, and COSEHC™ risk scores across sex and diabetic status subgroups. The results from each subgroup, assessed at baseline and at regular follow-up periods, are reported since the project initiation. Inference testing was performed to look for statistically significant differences between goal attainments rates between sexes. At-goal rates for systolic blood pressure (SBP) were improved during the 33 months of the study, with females achieving higher goal rates when compared to males. On the other hand, at-goal control rates for total and low-density lipoprotein (LDL) cholesterol (chol) were better in males compared to females. Diabetic patients had lower at-goal rates for SBP and triglycerides but higher rates for LDL-chol. The LDL-chol at-goal rates were higher for males, while high-density lipoprotein (HDL)-chol rates were higher for females. Utilization of antihypertensive medications was similar during and after the baseline period for both men and women. Patients taking two or more antihypertensive medications had higher mean COSEHC™-11 scores compared to those on monotherapy. With treatment, hypertensive patients can reach SBP and cholesterol goals; however, population-wide improvement in treatment goal adherence continues to be a challenge for physicians. The COSEHC™ GVRM Study shows, however, that continuous monitoring and feedback to physicians of accurate longitudinal data is an effective tool in achieving better control rates of cardiovascular risk factors.
cardiovascular risk; coronary heart disease; dyslipidemia; electronic medical records; hypertension; metabolic syndrome
To identify the chromosomal location of the gene involved in the pathogenesis of cavitary optic disc anomalies in a large pedigree with autosomal dominant inheritance of disease.
Linkage analysis of a pedigree affected with cavitary optic disc anomalies.
Optic disc photographs were examined for the presence of cavitary optic disc anomalies. Sixteen affected family members and one obligate carrier were identified and studied with linkage analysis using both microarrays of single nucleotide polymorphisms (SNPs) and short tandem repeat polymorphism (STRP) markers.
Multipoint linkage analysis of SNP genotypes yielded a maximum nonparametric LOD score of 21.7 with markers located on chromosome 12q. Linkage was confirmed with 16 STRP markers in the 12q region. A maximum two point LOD score of 4.06 (Θ=0) was obtained with marker D12S1700. The disease interval defined by observed recombinants is 9.1 cM, which corresponds to 13.5 Mbp. Three candidate genes (GDF-11, NEUROD4, and WIF1) in the chromosome 12q locus were evaluated as possible disease-causing genes. No mutations were detected in the coding sequence of these genes.
The discovery of the chromosomal location of a gene responsible for cavitary optic disc anomalies is a key step in identifying the genetic basis of this condition and may ultimately provide important insight into the pathogenesis of more common optic nerve diseases such as normal tension glaucoma and primary open angle glaucoma.
Since 2009 UK GPs have been incentivised to use depression severity scores to monitor patients’ response to treatment after 5–12 weeks of treatment.
To examine the association between the severity scores obtained and follow-up questionnaires to monitor depression and subsequent changes made to the treatment of it.
Design and setting
A retrospective cohort study utilising routine primary care records was conducted between April 2009 and March 2011 in 13 general practices recruited from within Hampshire, Wiltshire, and Southampton City primary care trusts.
Records were examined of 604 patients who had received a new diagnosis of depression since 1 April 2009, and who had completed the nine-item depression scale of the Patient Health Questionnaire (PHQ-9) at initial diagnosis and a subsequent PHQ-9 within 6 months. The main outcome measure was the odds ratio (OR) for a change in depression management. Change in management was defined as change in antidepressant drug prescription, dose, or referral.
Controlling for the effects of potentially confounding factors, patients who showed an inadequate response in score change at the time of second assessment were nearly five times as likely to experience a subsequent change to treatment in comparison with those who showed an adequate response (OR 4.72, 95% confidence interval = 2.83 to 7.86).
GPs’ decisions to change treatment or to make referrals following a second PHQ-9 appear to be in line with guidance from the National Institute for Health and Clinical Excellence for the monitoring of depression in primary care. Although the present study demonstrates an association between a lack of change in questionnaire scores and treatment changes, the extent to which scores influence choice and whether they are associated with improvements in depression outcomes is an important area for further research.
depression; patient monitoring; primary care
Antidepressants are among the most commonly prescribed drugs in primary care in England and their use is increasing. This is largely due to longer durations of treatment of depression. Observational studies have shown some differences in adverse outcomes associated with different antidepressant drugs but relatively little is known about their relative safety particularly with long term use. The primary aim of this study is to determine the relative and absolute risks of pre-defined adverse events comparing different classes of antidepressant drugs in adults aged under 65 years and diagnosed with depression.
The study will identify a cohort of patients with a first recorded diagnosis of depression between 1/1/2000 and 31/07/2011, and made between the ages of 20 to 64 years using a large primary care database (QResearch). Patients will be followed up until 1/08/2012. Details of all prescriptions for antidepressants in patients in the cohort will be extracted, including the date of each prescription, the type of antidepressant drug, the dose and total quantity prescribed. Prospectively recorded data will be used to ascertain information on adverse outcomes that occurred during follow-up and after entry into the cohort. These are: all-cause mortality, suicide, attempted suicide/self-harm, sudden death, antidepressant overdose/poisoning, myocardial infarction, stroke/transient ischaemic attack, cardiac arrhythmia, epilepsy/seizures, upper gastrointestinal bleeding, falls, fractures, adverse drug reactions and motor vehicle crashes. Cox proportional hazard models will be used to estimate the association of the outcomes with class of antidepressant drug adjusting for potential confounding variables. The analyses will also examine associations by duration and dose and with the most frequently prescribed individual antidepressant drugs. Self-controlled case series analyses will be used to estimate the relative incidence of the outcomes of interest for defined time periods of antidepressant use.
The results of this study will help to establish the relative safety and balance of risks for different antidepressant drugs in people aged under 65.
Antidepressants; Depression; Cohort; Safety
We examined the feasibility and acceptability of an HIV prevention intervention for African American adolescents delivered via mobile cell phones and looked at intervention-related changes in beliefs and sexual behaviors. We used a longitudinal one-group comparison design with data collected at three points. Forty adolescents, 13–18 years old, participated in the Becoming a Responsible Teen intervention followed by the delivery of daily multimedia messages for 3 months. The mobile-cell-phone enhanced intervention was feasible and acceptable to the participants. Greater HIV knowledge, improved attitudes toward condoms, and increased perceived HIV risk scores were observed with older adolescents (16–18 years old). Behavior trends showed a decrease in the number of times participants reported engaging in unprotected sexual intercourse over the previous 2 months. Mobile-cell-phone multimedia-text-messaging boosters tested in this study provided preliminary evidence of efficacy of the enhanced HIV prevention intervention for African American youth.
African American youth; feasibility study; HIV prevention; mobile cell phones; text messaging; multimedia
The early-diverging eudicot order Trochodendrales contains only two monospecific genera, Tetracentron and Trochodendron. Although an extensive fossil record indicates that the clade is perhaps 100 million years old and was widespread throughout the Northern Hemisphere during the Paleogene and Neogene, the two extant genera are both narrowly distributed in eastern Asia. Recent phylogenetic analyses strongly support a clade of Trochodendrales, Buxales, and Gunneridae (core eudicots), but complete plastome analyses do not resolve the relationships among these groups with strong support. However, plastid phylogenomic analyses have not included data for Tetracentron. To better resolve basal eudicot relationships and to clarify when the two extant genera of Trochodendrales diverged, we sequenced the complete plastid genome of Tetracentron sinense using Illumina technology. The Tetracentron and Trochodendron plastomes possess the typical gene content and arrangement that characterize most angiosperm plastid genomes, but both genomes have the same unusual ∼4 kb expansion of the inverted repeat region to include five genes (rpl22, rps3, rpl16, rpl14, and rps8) that are normally found in the large single-copy region. Maximum likelihood analyses of an 83-gene, 88 taxon angiosperm data set yield an identical tree topology as previous plastid-based trees, and moderately support the sister relationship between Buxaceae and Gunneridae. Molecular dating analyses suggest that Tetracentron and Trochodendron diverged between 44-30 million years ago, which is congruent with the fossil record of Trochodendrales and with previous estimates of the divergence time of these two taxa. We also characterize 154 simple sequence repeat loci from the Tetracentron sinense and Trochodendron aralioides plastomes that will be useful in future studies of population genetic structure for these relict species, both of which are of conservation concern.
H2S synthesis inhibitors (HSSI) have been shown to impact respiratory control. For instance, the HSSI hydroxylamine (HA) decreases the respiratory discharge rate from isolated medullary sections, and HA in addition to other HSSIs propargylglycine and amino-oxyacetic acid (AOAA) have been found to reduce hypoxic responsiveness. Objectives: The aim of this study was to determine if administration of HSSIs could improve respiratory stability in an intact organism prone to recurrent central apneas.
Saline and HSSI compounds were administered to C57BL/6J mice (n = 24), a strain predisposed to recurrent central apneas, prior to measurement of hypoxic and posthypoxic ventilatory behavior.
Administration of HA and AOAA resulted in a significantly smaller percentage of animals expressing one or more apneas during reoxygenation compared to saline control, and animals given AOAA demonstrated a smaller coefficient of variation for frequency during reoxygenation, a marker suggesting greater respiratory stability. This occurred despite varying effects of the three HSSI compounds on hypoxic ventilatory response.
Instability and pause expression are improved by targeting H2S synthesis, an effect not predicted by effects on hypoxic responsiveness.
Hypoxia; Respiratory control; Apnea; Hydrogen sulfide
Accuracy of motor axon regeneration becomes an important issue in the development of a nerve tube for motor nerve repair. Dispersion of regeneration across the nerve tube may lead to misdirection and polyinnervation. In this study, we present a series of methods to investigate the accuracy of regeneration, which we used to compare regeneration across autografts and single lumen poly(lactic-co-glycolic acid) (PLGA) nerve tubes. We also present the concept of the multichannel nerve tube that may limit dispersion by separately guiding groups of regenerating axons.
Simultaneous tracing of the tibial and peroneal nerves with fast blue (FB) and diamidino yellow (DY), 8 weeks after repair of a 1-cm nerve gap in the rat sciatic nerve, was performed to determine the percentage of double-projecting motoneurons. Sequential tracing of the peroneal nerve with DY 1 week before and FB 8 weeks after repair was performed to determine the percentage of correctly directed peroneal motoneurons.
In the cases in which there was successful regeneration across single lumen nerve tubes, more motoneurons had double projections to both the tibial and peroneal nerve branches after single lumen nerve tube repair (21.4%) than after autograft repair (5.9%). After multichannel nerve tube repair, this percentage was slightly reduced (16.9%), although not significantly. The direction of regeneration was nonspecific after all types of repair.
Retrograde tracing techniques provide new insights into the process of regeneration across nerve tubes. The methods and data presented in this study can be used as a basis in the development of a nerve tube for motor nerve repair.
misdirection; axon targeting; double labeling; peripheral nerve regeneration; rat sciatic nerve model; retrograde tracing
Background. Few studies have been done that characterize basal cell carcinoma (BCC) in Asians because this tumor is relatively uncommon in this population group. Objective. To characterize BCC in Asians. Methods. We retrospectively examined fifteen patient variables and eight tumor variables of ten Asian patients with BCC and compared these results to those of thirty matched Caucasian controls with BCC. Results. Asians developed their first BCC at an older age than the age of first BCC in Caucasian controls (68.9 years versus 58.3 years; P < 0.05). During their lifetime, Asians had fewer BCCs than the number of BCCs in Caucasian controls (1.11 versus 5.41; P < 0.02), despite a similar estimated lifetime daily sun exposure (hours/day) for both groups. Compared to BCCs in Caucasian controls, a higher percentage of BCCs in Asians were clinically pigmented (50.0% versus 3.3%; P < 0.01). Conclusion. Asians develop BCCs later in life and develop fewer BCCs over their lifetime than Caucasians, despite similar estimated lifetime daily sun exposure. This finding is probably due to skin pigmentation in Asians being more protective of ultraviolet light than skin pigmentation in Caucasians.
Recent dogma suggested that marine mammals are not at risk of decompression sickness due to a number of evolutionary adaptations. Several proposed adaptations exist. Lung compression and alveolar collapse that terminate gas-exchange before a depth is reached where supersaturation is significant and bradycardia with peripheral vasoconstriction affecting the distribution, and dynamics of blood and tissue nitrogen levels. Published accounts of gas and fat emboli and dysbaric osteonecrosis in marine mammals and theoretical modeling have challenged this view-point, suggesting that decompression-like symptoms may occur under certain circumstances, contrary to common belief. Diagnostic imaging modalities are invaluable tools for the non-invasive examination of animals for evidence of gas and have been used to demonstrate the presence of incidental decompression-related renal gas accumulations in some stranded cetaceans. Diagnostic imaging has also contributed to the recognition of clinically significant gas accumulations in live and dead cetaceans and pinnipeds. Understanding the appropriate application and limitations of the available imaging modalities is important for accurate interpretation of results. The presence of gas may be asymptomatic and must be interpreted cautiously alongside all other available data including clinical examination, clinical laboratory testing, gas analysis, necropsy examination, and histology results.
computed tomography; ultrasound; magnetic resonance imaging; cetacean; decompression sickness; bends; pinniped; gas bubbles
Recombination is a major force for generating HIV-1 diversity and produces numerous recombinants circulating in the human population. We previously established a cell-based system using green fluorescent protein gene (gfp) as a reporter to study the mechanisms of HIV-1 recombination. We now report an improved system capable of detecting recombination using authentic viral sequences. Frameshift mutations were introduced into the gag gene o that parental viruses do not express full-length Gag; however, recombination can generate a progeny virus that expresses a functional Gag. We demonstrate that this Gag reconstitution assay can be used to detect recombination between two group M HIV-1 variants of same or different subtypes. Using both gfp and gag assays, we found that, similar to group M viruses, group O viruses also recombine frequently. When recombination between a group M virus and a group O virus was examined, we found three distinct barriers for intergroup recombination. First, similar to recombination within group M viruses, intergroup recombination is affected by the identity of the dimerization initiation signal (DIS); variants with the same DIS recombined at a higher rate than those with different DIS. Second, using the gfp recombination assay, we showed that intergroup recombination occurs much less frequently than intragroup recombination, even though the gfp target sequence is identical in all viruses. Finally, Gag reconstitution between variants from different groups is further reduced compared with GFP, indicating that sequence divergence interferes with recombination efficiency in the gag gene. Compared with identical sequences, we estimate that recombination rates are reduced by 3-fold and 10–13-fold when the target regions in gag contain 91% and 72–73% sequence identities, respectively. These results show that there are at least three distinct mechanisms preventing exchange of genetic information between divergent HIV-1 variants from different groups.
GFP; Gag; group M; group O; reconstitution
To systematically review the research findings regarding the associations between psychosocial factors and adjustment to chronic pain in persons with physical disabilities.
A key word literature search was conducted using articles listed in PubMed, PsychInfo, and CINAHL up to March 2010, and manual searches were made of all retrieved articles to identify published articles that met the review inclusion criteria.
To be included in the review, articles needed to (1) be written in English, (2) include adults with a physical disability who report having pain, (3) include at least 1 measure of a psychosocial predictor domain, (4) include at least 1 criterion measure of pain or patient functioning, and (5) report the results of associations between the psychosocial factors and criterion measures used in the study. Twenty-nine studies met the inclusion criteria.
Three reviewers tabulated study details and findings.
The disability groups studied included spinal cord injury (SCI), acquired amputation, cerebral palsy (CP), multiple sclerosis (MS), and muscular dystrophy (MD). Psychosocial factors were shown to be significantly associated with pain and dysfunction in all disability groups. The psychosocial factors most closely associated with pain and dysfunction across the samples included (1) catastrophizing cognitions; (2) task persistence, guarding, and resting coping responses; and (3) perceived social support and solicitous responding social factors. Pain-related beliefs were more strongly associated with pain and dysfunction in the SCI, CP, MS, and MD groups than in the acquired amputation group.
The findings support the importance of psychosocial factors as significant predictors of pain and functioning in persons with physical disabilities. Clinical trials to test the efficacy of psychosocial treatments for pain and dysfunction are warranted, as are studies to determine whether psychosocial factors have a causal influence on pain and adjustment in these populations.
Amputation; Pain; Psychological adaptation
Lady beetles typically lay eggs in clusters, and clutch-mates that emerge near to each other might benefit in multiple ways. For example, lady beetle larvae are attracted to the pheromone released by aphids under attack. Thus, one potential advantage to larvae emerging as a group is if one larva captures an aphid, others can share in consuming the same aphid. Sharing a meal likely reduces the per capita food intake of a hatchling, but it might also provide enough nutrition to prevent death by starvation during a particularly vulnerable stage. In an assay of the behavior of two-spotted lady beetles (Adalia bipunctata), larvae were attracted to chemical cues from damaged aphids, corroborating previous research. Densities of A. bipunctata hatchlings were then manipulated to test whether the presence of clutch-mates increasesed the probability of capturing prey, and the survivorship of hatchlings. In one experiment, a single aphid was placed with a number of lady beetle hatchlings ranging from 1 to 10 in a small arena for 72 hours to evaluate prey capture effectiveness and hatchling survival. As the initial density of lady beetle hatchlings increased, their prey capture rate increased. At the same time, survival of the hatchlings was not affected by their initial density. Five experiments were performed on individual fava bean plants by varying densities of aphids and lady beetle hatchlings to evaluate lady beetle survivorship measured after five days. In all five on-plant experiments, increasing the initial number of lady beetle larvae did not improve their survival. Lady beetle larvae shared meals during the small scale experiments, but that behavior did not improve their survivorship under any of the experimental conditions.
Aphididae; Coccinellidae; foraging behavior
We sought to determine the risk of tumor incisional recurrence in patients receiving surgery and postoperative radiation therapy for locally advanced sinonasal malignancies. Medical records for 70 patients newly diagnosed with nonmetastatic American Joint Committee on Cancer stage II to stage IV sinonasal malignancies between 1991 and 2003 were retrospectively reviewed. Patient demographics and tumor variables were recorded. All patients underwent upfront surgical resection with postoperative three-dimensional conformal proton beam radiotherapy. Recurrence and survival-related outcomes were recorded. Two patients with squamous cell carcinoma had pathologically confirmed tumor recurrence at the incision site. The actuarial risk of incisional recurrence for the entire group at 1 year was 3%. One of the two patients had a maxillary sinus tumor and developed isolated skin recurrence along the transfacial incision. The other patient with an ethmoid sinus tumor developed isolated dural recurrence along the craniotomy incision. Both patients underwent multiple courses of salvage surgery and radiation therapy. One was successfully salvaged locally but developed distant metastases and the other died of local recurrence. Tumor seeding following transfacial and craniotomy surgery can occur, especially for squamous cell carcinoma. Sound oncological surgical technique, even when utilizing these difficult surgical approaches, is important to minimize incisional recurrence.
Incisional recurrence; wound metastasis; tumor implantation; anterior skull base surgery; transfacial surgery
Alternative splicing is a vast source of biological regulation and diversity that is misregulated in cancer and other diseases. To investigate global control of alternative splicing in human cells, we analyzed splicing of mRNAs encoding Bcl2-family apoptosis factors in a genome-wide siRNA screen. The screen identified many novel regulators of Bcl-x and Mcl1 splicing, notably an extensive network of cell cycle factors linked to aurora kinase A. Drugs or siRNAs that induce mitotic arrest promoted pro-apoptotic splicing of Bcl-x, Mcl1, and caspase-9, and altered splicing of other apoptotic transcripts. This response preceded mitotic arrest, indicating coordinated upregulation of pro-death splice variants that promotes apoptosis in arrested cells. These shifts corresponded to post-translational turnover of splicing regulator ASF/SF2, which directly binds and regulates these target mRNAs and globally regulates apoptosis. Broadly, our results reveal an alternative splicing network linking cell cycle control to apoptosis.
Dipsticks are one of the most commonly used near-patient tests in primary care, but few clinical or dipstick algorithms have been rigorously developed.
To confirm whether previously documented clinical and dipstick variables and algorithms predict laboratory diagnosis of urinary tract infection (UTI).
Design of study
A total of 434 adult females with suspected lower UTI had bacteriuria assessed using the European Urinalysis Guidelines.
Sixty-six per cent of patients had confirmed UTI. The predictive values of nitrite, leucocyte esterase (+ or greater), and blood (haemolysed trace or greater) were confirmed (independent multivariate odds ratios = 5.6, 3.5, and 2.1 respectively). The previously developed dipstick rule — based on presence of nitrite, or both leucocytes and blood — was moderately sensitive (75%) but less specific (66%; positive predictive value [PPV] 81%, negative predictive value [NPV] 57%). Predictive values were improved by varying the cut-off point: NPV was 76% for all three dipstick results being negative; the PPV was 92% for having nitrite and either blood or leucocyte esterase. Urine offensive smell was not found to be predictive in this sample; for a clinical score using the remaining three predictive clinical features (urine cloudiness, dysuria, and nocturia), NPV was 67% for none of the features, and PPV was 82% for three features.
A clinical score is of limited value in increasing diagnostic precision. Dipstick results can modestly improve diagnostic precision but poorly rule out infection. Clinicians need strategies to take account of poor NPVs.
algorithms, clinical scoring; diagnosis, urinary tract infection; primary care; urinalysis
Recently, a transoral robotic-assisted technique to access the thyroid gland has been introduced. Despite the advantages this approach may have over other minimally invasive and robotic-assisted techniques, we found that the placement of the camera through the floor of mouth led to restricted freedom of movement. We describe our modification to this technique to overcome this problem. In a study using two fresh human cadavers, the camera port of the da Vinci robot was placed in the midline oral vestibule instead of the floor of the mouth. A transoral thyroidectomy and central neck dissection was successfully performed. Our modification led to an unfettered view of the central neck and allowed for a total thyroidectomy and central neck dissection. Our modification of transoral robotic-assisted thyroidectomy provides superior access to the central compartment of the neck over other robotic-assisted thyroidectomy techniques.
Electronic supplementary material
The online version of this article (doi:10.1007/s11701-011-0287-2) contains supplementary material, which is available to authorized users.
Transoral thyroidectomy; Thyroid; Robotic-assisted surgery; Robot; Minimally invasive; Central neck
The purpose of this research is to develop and evaluate methods for conducting cluster randomised trials in a primary care database that contains electronic patient records for large numbers of family practices. Cluster randomised trials are trials in which the units allocated represent groups of individuals, in this case family practices and their registered patients. Cluster randomised trials often suffer from the limitation that they include too few clusters, leading to problems of insufficient power and only imprecise estimation of the intraclass correlation coefficient, a key design parameter. This difficulty might be overcome by utilising databases that already hold electronic patient records for large numbers of practices. The protocol describes one application: a study of antibiotic prescribing for acute respiratory infection; a second protocol outlines an intervention in a less frequent chronic condition of public health importance, stroke.
The objective of the study is to implement a cluster randomised trial to test the effectiveness of an electronic record-based intervention at achieving a reduction in antibiotic prescribing at consultations for respiratory illness in patients aged 18 and 59 years old in intervention family practices as compared with controls. Family practices will be recruited from the practices that presently contribute data to the UK General Practice Research Database (GPRD). Following randomisation, electronic prompts will be installed remotely at intervention practices to promote adherence with evidence-based standards of medical practice. The intervention was developed through qualitative research at non-intervention practices. Data for outcome assessment will be obtained from anonymised electronic patient records that are routinely collected into GPRD. This protocol outlines the proposed study designs, data sources, sample size requirements, analysis methods and dissemination plans. Ethical issues are also discussed.
Results from this study will provide methodological evidence concerning the use of electronic patient records and databases for implementing cluster randomised trials in primary care. The study will also provide substantive findings in respect of electronic record-based interventions to reduce antibiotic prescribing in primary care.
Current Controlled Trials ISRCTN 47558792.
Each viral particle of HIV-1, the infectious agent of AIDS, contains two copies of the full-length viral genomic RNA. Encapsidating two copies of genomic RNA is one of the characteristics of the retrovirus family. The two RNA molecules are both positive-sense and often identical; furthermore, each RNA encodes the full complement of genetic information required for viral replication. The two strands of RNA are intricately entwined within the core of the mature infectious virus as a ribonuclear complex with the viral proteins, including nucleocapsid. Multiple steps in the biogenesis of the genomic full-length RNA are involved in achieving this location and dimeric state. The viral sequences and proteins involved in the process of RNA dimerization, both for the initial interstrand contact and subsequent steps that result in the condensed, stable conformation of the genomic RNA, are outlined in this review. In addition, the impact of the dimeric state of HIV-1 viral RNA is discussed with respect to its importance in efficient viral replication and, consequently, the potential development of antiviral strategies designed to disrupt the formation of dimeric RNA.
HIV-1; Genome; RNA; Dimerization; Recombination; Maturation
We have characterized microsomal systems and measured the levels of microsomal cytochrome P450 1A1 (CYP1A1) and ethoxyresorufin-O-deethylase activity in multiple internal organs of male and female white-sided dolphin (Lagenorhynchus acutus) from the northwest Atlantic Ocean. Internal organs were sampled within 24 hours of death, sometimes in a period of hours, collection times which are significantly less than usually seen for marine mammals. Tissue autolysis, as assessed by histological analysis of liver, was minimal to none in all individuals. Total P420 did not correlate with time from death to sampling, suggesting that it is a poor indicator of P450 degradation in cetacean tissues where perfusion isn’t practical. The total hepatic microsomal P450 content, cytochrome b5 content, and NADPH-cytochrome c (P450) reductase (CPR) activity averaged 0.29 nmol mg−1, 0.12 nmol mg−1, and 238 nmol mg−1 min−1, respectively. Microsomal CPR activity in liver was higher than that in lung and kidney, and was higher than that reported in liver of most other cetacean species. Immunodetected CYP1A1 content was low in all organs, less than 3 pmoles CYP1A equivalents mg−1. EROD activity ranged from 9 – 376 pmoles mg−1 min−1 and was greater in liver than in other tissues. Hepatic microsomal EROD activity and CYP1A1 content did not correlate. However, hepatic EROD activity, but not CYP1A1 protein content, was well correlated with both total PCB and Σmono-ortho PCB concentrations in blubber. Length, as a proxy for age, did not correlate with hepatic EROD activity or CYP1A1 protein levels, and sex did not influence the relationship between EROD and contaminant concentrations. We cannot easily control for the extent of tissue degradation in cetacean studies nor do we have a complete history of these animals. Therefore, other factors such as degradation or hormonal state may have a role in the observed relationships. Yet, as in other mammals, hepatic tissues appear to be a major site of CYP1A1 expression and probably of biotransformation of CYP1A substrates in white-sided dolphin. The expression of an EROD catalyst in liver likely reflects induction by PCBs, but the P450 enzyme catalyzing hepatic EROD activity in these whales may not be CYP1A1.
cytochrome P450 1A1; CYP1A1; white-sided dolphin; polychlorinated biphenyl; PCB
Increasingly, patterned cell culture environments are becoming a relevant technique to study cellular characteristics, and many researchers believe in the need for 3D environments to represent in vitro experiments which better mimic in vivo qualities 1-3. Studies in fields such as cancer research 4, neural engineering 5, cardiac physiology 6, and cell-matrix interaction7,8have shown cell behavior differs substantially between traditional monolayer cultures and 3D constructs.
Hydrogels are used as 3D environments because of their variety, versatility and ability to tailor molecular composition through functionalization 9-12. Numerous techniques exist for creation of constructs as cell-supportive matrices, including electrospinning13, elastomer stamps14, inkjet printing15, additive photopatterning16, static photomask projection-lithography17, and dynamic mask microstereolithography18. Unfortunately, these methods involve multiple production steps and/or equipment not readily adaptable to conventional cell and tissue culture methods. The technique employed in this protocol adapts the latter two methods, using a digital micromirror device (DMD) to create dynamic photomasks for crosslinking geometrically specific poly-(ethylene glycol) (PEG) hydrogels, induced through UV initiated free radical polymerization. The resulting "2.5D" structures provide a constrained 3D environment for neural growth. We employ a dual-hydrogel approach, where PEG serves as a cell-restrictive region supplying structure to an otherwise shapeless but cell-permissive self-assembling gel made from either Puramatrix or agarose. The process is a quick simple one step fabrication which is highly reproducible and easily adapted for use with conventional cell culture methods and substrates.
Whole tissue explants, such as embryonic dorsal root ganglia (DRG), can be incorporated into the dual hydrogel constructs for experimental assays such as neurite outgrowth. Additionally, dissociated cells can be encapsulated in the photocrosslinkable or self polymerizing hydrogel, or selectively adhered to the permeable support membrane using cell-restrictive photopatterning. Using the DMD, we created hydrogel constructs up to ~1mm thick, but thin film (<200 μm) PEG structures were limited by oxygen quenching of the free radical polymerization reaction. We subsequently developed a technique utilizing a layer of oil above the polymerization liquid which allowed thin PEG structure polymerization.
In this protocol, we describe the expeditious creation of 3D hydrogel systems for production of microfabricated neural cell and tissue cultures. The dual hydrogel constructs demonstrated herein represent versatile in vitro models that may prove useful for studies in neuroscience involving cell survival, migration, and/or neurite growth and guidance. Moreover, as the protocol can work for many types of hydrogels and cells, the potential applications are both varied and vast.