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1.  A Role for the Malignant Brain Tumour (MBT) Domain Protein LIN-61 in DNA Double-Strand Break Repair by Homologous Recombination 
PLoS Genetics  2013;9(3):e1003339.
Malignant brain tumour (MBT) domain proteins are transcriptional repressors that function within Polycomb complexes. Some MBT genes are tumour suppressors, but how they prevent tumourigenesis is unknown. The Caenorhabditis elegans MBT protein LIN-61 is a member of the synMuvB chromatin-remodelling proteins that control vulval development. Here we report a new role for LIN-61: it protects the genome by promoting homologous recombination (HR) for the repair of DNA double-strand breaks (DSBs). lin-61 mutants manifest numerous problems associated with defective HR in germ and somatic cells but remain proficient in meiotic recombination. They are hypersensitive to ionizing radiation and interstrand crosslinks but not UV light. Using a novel reporter system that monitors repair of a defined DSB in C. elegans somatic cells, we show that LIN-61 contributes to HR. The involvement of this MBT protein in HR raises the possibility that MBT–deficient tumours may also have defective DSB repair.
Author Summary
The genome is continually under threat from exogenous sources of DNA damage, as well as from sources that originate within the cell. DNA double-strand breaks (DSBs) are arguably the most problematic type of damage as they can cause dangerous chromosome rearrangements, which can lead to cancer, as well as mutation at the break site and/or cell death. A complex network of molecular pathways, collectively referred to as the DNA damage response (DDR), have evolved to protect the cell from these threats. We have discovered a new DDR factor, LIN-61, that promotes the repair of DSBs. This is a novel and unexpected role for LIN-61, which was previously known to act as a regulator of gene transcription during development.
doi:10.1371/journal.pgen.1003339
PMCID: PMC3591299  PMID: 23505385
2.  COM-1 Promotes Homologous Recombination during Caenorhabditis elegans Meiosis by Antagonizing Ku-Mediated Non-Homologous End Joining 
PLoS Genetics  2013;9(2):e1003276.
Successful completion of meiosis requires the induction and faithful repair of DNA double-strand breaks (DSBs). DSBs can be repaired via homologous recombination (HR) or non-homologous end joining (NHEJ), yet only repair via HR can generate the interhomolog crossovers (COs) needed for meiotic chromosome segregation. Here we identify COM-1, the homolog of CtIP/Sae2/Ctp1, as a crucial regulator of DSB repair pathway choice during Caenorhabditis elegans gametogenesis. COM-1–deficient germ cells repair meiotic DSBs via the error-prone pathway NHEJ, resulting in a lack of COs, extensive chromosomal aggregation, and near-complete embryonic lethality. In contrast to its yeast counterparts, COM-1 is not required for Spo11 removal and initiation of meiotic DSB repair, but instead promotes meiotic recombination by counteracting the NHEJ complex Ku. In fact, animals defective for both COM-1 and Ku are viable and proficient in CO formation. Further genetic dissection revealed that COM-1 acts parallel to the nuclease EXO-1 to promote interhomolog HR at early pachytene stage of meiotic prophase and thereby safeguards timely CO formation. Both of these nucleases, however, are dispensable for RAD-51 recruitment at late pachytene stage, when homolog-independent repair pathways predominate, suggesting further redundancy and/or temporal regulation of DNA end resection during meiotic prophase. Collectively, our results uncover the potentially lethal properties of NHEJ during meiosis and identify a critical role for COM-1 in NHEJ inhibition and CO assurance in germ cells.
Author Summary
Sexually reproducing animals create germ cells via meiosis, a cell division program that requires the induction and faithful repair of DNA double-strand breaks (DSBs). Meiotic DSBs are typically repaired via homologous recombination (HR), an error-free repair pathway that generates transient links between homologous chromosomes, named crossovers (COs), which are needed for proper chromosome segregation. To date, it is unclear how germ cells channel these programmed DSBs into HR and not into error-prone DSB repair pathways such as non-homologous end joining (NHEJ). We used the genetically tractable animal model Caenorhabditis elegans to study the mechanisms underlying the strong HR bias in germ cells. Here, we identify COM-1, the worm homolog of CtIP, as a crucial regulator of meiotic DSB repair pathway choice: COM-1 effectively blocks the action of the NHEJ complex Ku, thereby assuring correct repair via HR. In addition, we show that unscheduled NHEJ activity during meiosis leads to a lack of COs, extensive chromosomal aggregation, and near-complete embryonic lethality. Further genetic dissection also revealed a redundant and stage-specific role for COM-1 in meiotic HR. Our work thus establishes COM-1/CtIP as a caretaker of germline genome stability and unveils meiotic NHEJ as a potent source of chromosomal aberrations in newborns.
doi:10.1371/journal.pgen.1003276
PMCID: PMC3567172  PMID: 23408909
3.  Genome-wide association study of body height in African Americans: the Women's Health Initiative SNP Health Association Resource (SHARe) 
Human Molecular Genetics  2011;21(3):711-720.
Height is a complex trait under strong genetic influence. To date, numerous genetic loci have been associated with height in individuals of European ancestry. However, few large-scale discovery genome-wide association studies (GWAS) of height in minority populations have been conducted and thus information about population-specific height regulation is limited. We conducted a GWA analysis of height in 8149 African-American (AA) women from the Women's Health Initiative. Genetic variants with P< 5 × 10−5 (n = 169) were followed up in a replication data set (n = 20 809) and meta-analyzed in a total of 28 958 AAs and African-descent individuals. Twelve single-nucleotide polymorphisms (SNPs) representing 7 independent loci were significantly associated with height at P < 5 × 10−8. We identified novel SNPs in 17q23 (TMEM100/PCTP) and Xp22.3 (ARSE) reflecting population-specific regulation of height in AAs and replicated five loci previously reported in European-descent populations [4p15/LCORL, 11q13/SERPINH1, 12q14/HMGA2, 17q23/MAP3K3 (mitogen-activated protein kinase3) and 18q21/DYM]. In addition, we performed an admixture mapping analysis of height which is both complementary and supportive to the GWA analysis and suggests potential associations between ancestry and height on chromosomes 4 (4q21), 15 (15q26) and 17 (17q23). Our findings provide insight into the genetic architecture of height and support the investigation of non-European-descent populations for identifying genetic factors associated with complex traits. Specifically, we identify new loci that may reflect population-specific regulation of height and report several known height loci that are important in determining height in African-descent populations.
doi:10.1093/hmg/ddr489
PMCID: PMC3259012  PMID: 22021425
4.  Pheromonal bile acid 3-ketopetromyzonol sulfate primes the neuroendocrine system in sea lamprey 
BMC Neuroscience  2013;14:11.
Background
Vertebrate pheromones are known to prime the endocrine system, especially the hypothalamic-pituitary-gonadal (HPG) axis. However, no known pheromone molecule has been shown to modulate directly the synthesis or release of gonadotropin releasing hormone (GnRH), the main regulator of the HPG axis. We selected sea lamprey (Petromyzon marinus) as a model system to determine whether a single pheromone component alters the output of GnRH.
Sea lamprey male sex pheromones contain a main component, 7α, 12α, 24-trihydroxy-5α-cholan-3-one 24-sulfate (3 keto-petromyzonol sulfate or 3kPZS), which has been shown to modulate behaviors of mature females. Through a series of experiments, we tested the hypothesis that 3kPZS modulates both synthesis and release of GnRH, and subsequently, HPG output in immature sea lamprey.
Results
The results showed that natural male pheromone mixtures induced differential steroid responses but facilitated sexual maturation in both sexes of immature animals (χ2 = 5.042, dF = 1, p < 0.05). Exposure to 3kPZS increased plasma 15α-hydroxyprogesterone (15α-P) concentrations (one-way ANOVA, p < 0.05) and brain gene expressions (genes examined: three lamprey (l) GnRH-I transcripts, lGnRH-III, Jun and Jun N-terminal kinase (JNK); one-way ANOVA, p < 0.05), but did not alter the number of GnRH neurons in the hypothalamus in immature animals. In addition, 3kPZS treatments increased lGnRH peptide concentrations in the forebrain and modulated their levels in plasma. Overall, 3kPZS modulation of HPG axis is more pronounced in immature males than in females.
Conclusions
We conclude that a single male pheromone component primes the HPG axis in immature sea lamprey in a sexually dimorphic manner.
doi:10.1186/1471-2202-14-11
PMCID: PMC3599739  PMID: 23331321
Pheromone; Priming; HPG axis; GnRH; Steroid; Sexual dimorphism
5.  Plasma Exchange vs. Intravenous Immunoglobulin for Myasthenia Gravis Crisis: An Acute Hospital Cost Comparison Study 
Objective
To compare the short term financial costs of treating a patient in myasthenia gravis crisis (MGC) with intravenous immunoglobulin (IVIG) versus plasma exchange (PLEX).
Methods
An itemized comparative cost-minimization analysis of IVIG vs. plasma exchange for MGC was performed. Calculations were based on each therapy’s implementation cost, associated hospitalization times, and predicted cost to treat known complications. A cost superiority determination was proposed based on the total cost profile of each therapy.
Results
The difference in total cost favored IVIG over PLEX with an average savings of $22,326 per patient. Sensitivity analysis demonstrated that overall costs are highly dependent on IVIG dosing, hospital lengths of stay, and the number of plasma exchange days required.
Conclusions
The use of IVIG for MGC may be a short term cost minimizing therapy compared to PLEX. Additional prospective studies are required to evaluate the extended cost profile and efficacy of these therapies.
doi:10.1097/CND.0b013e31822c34dd
PMCID: PMC3291869  PMID: 22361692
6.  Laboratory Abnormalities in Patients with Myotonic Dystrophy Type 2 
Archives of neurology  2011;68(9):1180-1184.
Background
Myotonic dystrophy type-2 (DM2) is a recently discovered adult muscular dystrophy. Similar to DM1, this disease causes progressive debilitating weakness, clinical myotonia, and early cataracts, and is thought to cause widespread physiologic dysfunction of multiple organ systems.
Objective
To analyze and compile the laboratory abnormalities of patients with DM2.
Design
Baseline DM2 laboratory data were compiled representing 68 different types of laboratory tests and 1442 total studies.
Setting
University Medical Center.
Patients
Eighty-three adults with genetically confirmed or clinically probable DM2 were identified. Of these patients, 49 had documented baseline laboratory screening.
Main Outcome Measures
The individual frequencies of abnormal values in the population with DM2 studied.
Results
Of the 1442 studies, results for 359 (24.9%) were outside of their standard reference ranges. Of the 68 types of laboratory tests studied, 43 had values from fifteen or more different patients with DM2. The relative frequency of an abnormally elevated laboratory value was greater than 50% in several tests, including the levels of creatine kinase, total cholesterol, lactate dehydrogenase, and alanine aminotransferase (ALT). In addition, serum levels of immunoglobulin G (IgG) were low in 75% of all DM2 patients tested and absolute lymphocyte counts were low in 54% of all DM2 patients tested.
Conclusion
There is a high frequency of laboratory abnormalities in patients with DM2. These abnormalities provide insight into the widespread pathologic manifestations of DM2 and may form a basis for clinical monitoring and disease screening.
doi:10.1001/archneurol.2011.191
PMCID: PMC3429333  PMID: 21911698
7.  TRC40 can deliver short secretory proteins to the Sec61 translocon 
Journal of Cell Science  2012;125(15):3612-3620.
Summary
Whilst the co-translational translocation of nascent proteins across the mammalian endoplasmic reticulum (ER) is well defined, the capacity of this organelle for post-translational translocation is poorly delineated. Here we identify two human secretory protein precursors, apelin and statherin, as bona fide substrates for post-translational translocation across the ER membrane. Further studies, in combination with Hyalophora cecropia preprocecropin A (ppcecA), show that all three proteins bind to TRC40 and can utilise this component for their delivery to the ER membrane in a well-established in vitro system. However, ppcecA is not an obligate TRC40 substrate, and it can also be delivered to the ER by an alternative TRC40-independent pathway. Upon arrival at the ER membrane, these short secretory proteins appear to be ubiquitously transported across the ER membrane through the Sec61 translocon, apparently irrespective of their delivery route. We speculate that the post-translational translocation of secretory proteins in higher eukaryotes is more prevalent than previously acknowledged.
doi:10.1242/jcs.102608
PMCID: PMC3445324  PMID: 22505607
Asna 1; Endoplasmic reticulum; Post-translational translocation; Tail-anchored protein; WRB protein; Eeyarestatin I
8.  VHA-19 Is Essential in Caenorhabditis elegans Oocytes for Embryogenesis and Is Involved in Trafficking in Oocytes 
PLoS ONE  2012;7(7):e40317.
There is an urgent need to develop new drugs against parasitic nematodes, which are a significant burden on human health and agriculture. Information about the function of essential nematode-specific genes provides insight to key nematode-specific processes that could be targeted with drugs. We have characterized the function of a novel, nematode-specific Caenorhabditis elegans protein, VHA-19, and show that VHA-19 is essential in the germline and, specifically, the oocytes, for the completion of embryogenesis. VHA-19 is also involved in trafficking the oocyte receptor RME-2 to the oocyte plasma membrane and is essential for osmoregulation in the embryo, probably because VHA-19 is required for proper eggshell formation via exocytosis of cortical granules or other essential components of the eggshell. VHA-19 may also have a role in cytokinesis, either directly or as an indirect effect of its role in osmoregulation. Critically, VHA-19 is expressed in the excretory cell in both larvae and adults, suggesting that it may have a role in osmoregulation in C. elegans more generally, probably in trafficking or secretion pathways. This is the first time a role for VHA-19 has been described.
doi:10.1371/journal.pone.0040317
PMCID: PMC3388054  PMID: 22768351
9.  Genetic markers of ovarian follicle number and menopause in women of multiple ethnicities 
Human Genetics  2012;131(11):1709-1724.
Oocyte loss has a significant impact on fertility and somatic health. Yet, we know little about factors that impact this process. We sought to identify genetic variants associated with ovarian reserve (oocyte number as measured by antral follicle count, AFC). Based on recently published genome-wide scans that identified loci associated with age of menopause, we also sought to test our hypothesis that follicle number and menopausal age share underlying genetic associations. We analyzed menopause-related variants for association with follicle number in an independent population of approximately 450 reproductive-aged women of European and African ancestry; these women were assessed for AFC, anthropometric, clinical, and lifestyle factors. One SNP strongly associated with later menopausal age in Caucasian women (+1.07 ± 0.11 years) in previous work was also associated with higher follicle counts in Caucasians (+2.79 ± 1.67 follicles) in our study. This variant is within the Minichromosome Maintenance Complex Component 8 (MCM8) gene, which we found was expressed within oocytes in follicles of the human ovary. In genome-wide scans of AFC, we also identified one marginally genome-wide and several nominally significant SNPs within several other genes associated with follicle number in both ethnic groups. Further, there were overlapping variants associated with multiple ovarian reserve markers (AFC, serum hormone levels, menopausal age). This study provides the first evidence for direct genetic associations underlying both follicle number and menopause and identifies novel candidate genes. Genetic variants associated with ovarian reserve may facilitate discovery of genetic markers to predict reproductive health and lifespan in women.
Electronic supplementary material
The online version of this article (doi:10.1007/s00439-012-1184-0) contains supplementary material, which is available to authorized users.
doi:10.1007/s00439-012-1184-0
PMCID: PMC3470691  PMID: 22696150
10.  Occult infiltrating bi-ventricular papillary renal cell carcinoma metastasis found during coronary artery bypass graft surgery 
Metastatic papillary renal cell carcinoma (RCC) to the heart has never been reported. We report the case of a 73-year-old patient with papillary RCC metastatic to the left and right ventricles, found during a triple vessel coronary artery bypass graft surgery.
doi:10.5489/cuaj.11144
PMCID: PMC3328572  PMID: 22511433
11.  Ancestral Components of Admixed Genomes in a Mexican Cohort 
PLoS Genetics  2011;7(12):e1002410.
For most of the world, human genome structure at a population level is shaped by interplay between ancient geographic isolation and more recent demographic shifts, factors that are captured by the concepts of biogeographic ancestry and admixture, respectively. The ancestry of non-admixed individuals can often be traced to a specific population in a precise region, but current approaches for studying admixed individuals generally yield coarse information in which genome ancestry proportions are identified according to continent of origin. Here we introduce a new analytic strategy for this problem that allows fine-grained characterization of admixed individuals with respect to both geographic and genomic coordinates. Ancestry segments from different continents, identified with a probabilistic model, are used to construct and study “virtual genomes” of admixed individuals. We apply this approach to a cohort of 492 parent–offspring trios from Mexico City. The relative contributions from the three continental-level ancestral populations—Africa, Europe, and America—vary substantially between individuals, and the distribution of haplotype block length suggests an admixing time of 10–15 generations. The European and Indigenous American virtual genomes of each Mexican individual can be traced to precise regions within each continent, and they reveal a gradient of Amerindian ancestry between indigenous people of southwestern Mexico and Mayans of the Yucatan Peninsula. This contrasts sharply with the African roots of African Americans, which have been characterized by a uniform mixing of multiple West African populations. We also use the virtual European and Indigenous American genomes to search for the signatures of selection in the ancestral populations, and we identify previously known targets of selection in other populations, as well as new candidate loci. The ability to infer precise ancestral components of admixed genomes will facilitate studies of disease-related phenotypes and will allow new insight into the adaptive and demographic history of indigenous people.
Author Summary
Admixed individuals, such as African Americans and Latinos, arise from mating between individuals from different continents. Detailed knowledge about the ancestral origin of an admixed population not only provides insight regarding the history of the population itself, but also affords opportunities to study the evolutionary biology of the ancestral populations. Applying novel statistical methods, we analyzed the high-density genotype data of nearly 1,500 Mexican individuals from Mexico City, who are admixed among Indigenous Americans, Europeans, and Africans. The relative contributions from the three continental-level ancestral populations vary substantially between individuals. The European ancestors of these Mexican individuals genetically resemble Southern Europeans, such as the Spaniard and the Portuguese. The Indigenous American ancestry of the Mexicans in our study is largely attributed to the indigenous groups residing in the southwestern region of Mexico, although some individuals have inherited varying degrees of ancestry from the Mayans of the Yucatan Peninsula and other indigenous American populations. A search for signatures of selection, focusing on the parts of the genomes derived from an ancestral population (e.g. Indigenous American), identifies regions in which a genetic variant may have been favored by natural selection in that ancestral population.
doi:10.1371/journal.pgen.1002410
PMCID: PMC3240599  PMID: 22194699
12.  Rapid Molecular Detection Methods for Arboviruses of Livestock of Importance to Northern Europe 
Arthropod-borne viruses (arboviruses) have been responsible for some of the most explosive epidemics of emerging infectious diseases over the past decade. Their impact on both human and livestock populations has been dramatic. The early detection either through surveillance or diagnosis of virus will be a critical feature in responding and resolving the emergence of such epidemics in the future. Although some of the most important emerging arboviruses are human pathogens, this paper aims to highlight those diseases that primarily affect livestock, although many are zoonotic and some occasionally cause human mortality. This paper also highlights the molecular detection methods specific to each virus and identifies those emerging diseases for which a rapid detection methods are not yet developed.
doi:10.1155/2012/719402
PMCID: PMC3246798  PMID: 22219660
13.  Joint testing of genotype and ancestry association in admixed families 
Genetic epidemiology  2010;34(8):783-791.
Current genome-wide association studies (GWAS) often involve populations that have experienced recent genetic admixture. Genotype data generated from these studies can be used to test for association directly, as in a non-admixed population. As an alternative, these data can be used to infer chromosomal ancestry, and thus allow for admixture mapping. We quantify the contribution of allele-based and ancestry-based association testing under a family-design, and demonstrate that the two tests can provide non-redundant information. We propose a joint testing procedure, which efficiently integrates the two sources information. The efficiencies of the allele, ancestry and combined tests are compared in the context of a GWAS. We discuss the impact of population history and provide guidelines for future design and analysis of GWAS in admixed populations.
doi:10.1002/gepi.20520
PMCID: PMC3103820  PMID: 21031451
14.  Flavivirus-induced antibody cross-reactivity 
The Journal of General Virology  2011;92(Pt 12):2821-2829.
Dengue viruses (DENV) cause countless human deaths each year, whilst West Nile virus (WNV) has re-emerged as an important human pathogen. There are currently no WNV or DENV vaccines licensed for human use, yet vaccines exist against other flaviviruses. To investigate flavivirus cross-reactivity, sera from a human cohort with a history of vaccination against tick-borne encephalitis virus (TBEV), Japanese encephalitis virus (JEV) and yellow fever virus (YFV) were tested for antibodies by plaque reduction neutralization test. Neutralization of louping ill virus (LIV) occurred, but no significant neutralization of Murray Valley encephalitis virus was observed. Sera from some individuals vaccinated against TBEV and JEV neutralized WNV, which was enhanced by YFV vaccination in some recipients. Similarly, some individuals neutralized DENV-2, but this was not significantly influenced by YFV vaccination. Antigenic cartography techniques were used to generate a geometric illustration of the neutralization titres of selected sera against WNV, TBEV, JEV, LIV, YFV and DENV-2. This demonstrated the individual variation in antibody responses. Most sera had detectable titres against LIV and some had titres against WNV and DENV-2. Generally, LIV titres were similar to titres against TBEV, confirming the close antigenic relationship between TBEV and LIV. JEV was also antigenically closer to TBEV than WNV, using these sera. The use of sera from individuals vaccinated against multiple pathogens is unique relative to previous applications of antigenic cartography techniques. It is evident from these data that notable differences exist between amino acid sequence identity and mapped antigenic relationships within the family Flaviviridae.
doi:10.1099/vir.0.031641-0
PMCID: PMC3352572  PMID: 21900425
15.  Genetic variants and environmental factors associated with hormonal markers of ovarian reserve in Caucasian and African American women 
BACKGROUND
The ovarian reserve (number and quality of oocytes) is correlated with reproductive potential as well as somatic health, and is likely to have multiple genetic and environmental determinants. Several reproductive hormones are closely linked with the oocyte pool and thus can serve as surrogate markers of ovarian reserve. However, we know little about the underlying genes or genetic variants.
METHODS
We analyzed genetic variants across the genome associated with two hormonal markers of ovarian reserve, FSH and anti-Mullerian hormone, in a reproductively normal population of Caucasian (n = 232) and African American (n = 200) women, aged 25–45 years. We also examined the effects of environmental or lifestyle factors on ovarian reserve phenotypes.
RESULTS
We identified one variant approaching genome-wide significance (rs6543833; P= 8.07 × 10−8) and several nominal variants nearby and within the myeloid-associated differentiation marker-like (MYADML) gene, that were associated with FSH levels in African American women; these were validated in Caucasian women. We also discovered effects of smoking and oral contraceptive use on ovarian reserve phenotypes, with alterations in several reproductive hormones.
CONCLUSIONS
This work is the largest study on ovarian reserve in women of reproductive age and is the only genome-wide study on ovarian reserve markers. The genes containing or near the identified variants have no known roles in ovarian biology and represent interesting candidate genes for future investigations. The discovery of genetic markers may lead to better long-range predictions of declining ovarian function, with implications for reproductive and somatic health.
doi:10.1093/humrep/der391
PMCID: PMC3258032  PMID: 22116950
FSH / anti-Mullerian hormone; antral follicle count; single nucleotide polymorphism
17.  High-Throughput Measurement and Classification of Organic P in Environmental Samples 
Many types of organic phosphorus (P) molecules exist in environmental samples1. Traditional P measurements do not detect these organic P compounds since they do not react with colorimetric reagents2,3. Enzymatic hydrolysis (EH) is an emerging method for accurately characterizing organic P forms in environmental samples4,5. This method is only trumped in accuracy by Phosphorus-31 Nuclear Magnetic Resonance Spectroscopy (31P-NMR) -a method that is expensive and requires specialized technical training6. We have adapted an enzymatic hydrolysis method capable of measuring three classes of phosphorus (monoester P, diester P and inorganic P) to a microplate reader system7. This method provides researchers with a fast, accurate, affordable and user-friendly means to measure P species in soils, sediments, manures and, if concentrated, aquatic samples. This is the only high-throughput method for measuring the forms and enzyme-lability of organic P that can be performed in a standard laboratory. The resulting data provides insight to scientists studying system nutrient content and eutrophication potential.
doi:10.3791/2660
PMCID: PMC3197036  PMID: 21694686
18.  Evolutionary History of Rabies in Ghana 
Rabies virus (RABV) is enzootic throughout Africa, with the domestic dog (Canis familiaris) being the principal vector. Dog rabies is estimated to cause 24,000 human deaths per year in Africa, however, this estimate is still considered to be conservative. Two sub-Saharan African RABV lineages have been detected in West Africa. Lineage 2 is present throughout West Africa, whereas Africa 1a dominates in northern and eastern Africa, but has been detected in Nigeria and Gabon, and Africa 1b was previously absent from West Africa. We confirmed the presence of RABV in a cohort of 76 brain samples obtained from rabid animals in Ghana collected over an eighteen-month period (2007–2009). Phylogenetic analysis of the sequences obtained confirmed all viruses to be RABV, belonging to lineages previously detected in sub-Saharan Africa. However, unlike earlier reported studies that suggested a single lineage (Africa 2) circulates in West Africa, we identified viruses belonging to the Africa 2 lineage and both Africa 1 (a and b) sub-lineages. Phylogeographic Bayesian Markov chain Monte Carlo analysis of a 405 bp fragment of the RABV nucleoprotein gene from the 76 new sequences derived from Ghanaian animals suggest that within the Africa 2 lineage three clades co-circulate with their origins in other West African countries. Africa 1a is probably a western extension of a clade circulating in central Africa and the Africa 1b virus a probable recent introduction from eastern Africa. We also developed and tested a novel reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay for the detection of RABV in African laboratories. This RT-LAMP was shown to detect both Africa 1 and 2 viruses, including its adaptation to a lateral flow device format for product visualization. These data suggest that RABV epidemiology is more complex than previously thought in West Africa and that there have been repeated introductions of RABV into Ghana. This analysis highlights the potential problems of individual developing nations implementing rabies control programmes in the absence of a regional programme.
Author Summary
Rabies virus (RABV) is widespread throughout Africa, with the domestic dog being the principal vector. Dog rabies is estimated to cause 24,000 human deaths per year in Africa, however, this estimate is still considered to be conservative. Two sub-Saharan African RABV lineages (Africa 1 and 2) are thought to circulate in western and central Africa. We confirmed the presence of RABV in a cohort of 76 brain samples obtained from rabid animals in Ghana collected from 2007 to 2009. In addition we developed and tested a novel molecular diagnostic assay for the detection of RABV, which offers an alternative RABV diagnostic tool for African laboratories. Our analysis of the genetic sequences obtained confirmed all viruses to be RABV, however, unlike previous studies we detected two sub-Saharan African RABV viruses (Africa 1 and 2) in this cohort, which included a single virus previously undetected in West Africa. We suggest that there has been repeated introduction of new RABVs into Ghana over a prolonged period from other West African countries and more recently from eastern Africa. These observations further highlight the problems of individual developing nations implementing rabies control programmes at a local, rather than regional level.
doi:10.1371/journal.pntd.0001001
PMCID: PMC3071360  PMID: 21483707
19.  Imported Rabies, European Union and Switzerland, 2001–2010 
Emerging Infectious Diseases  2011;17(4):751-753.
doi:10.3201/eid1704.101154
PMCID: PMC3377407
Viruses; rabies; zoonoses; European Union; Switzerland; letter
20.  Detailed Analysis of Prehospital Interventions in Medical Priority Dispatch System Determinants 
Background:
Medical Priority Dispatch System (MPDS) is a type of Emergency Medical Dispatch (EMD) system used to prioritize 9-1-1 calls and optimize resource allocation. Dispatchers use a series of scripted questions to assign determinants to calls based on chief complaint and acuity.
Objective:
We analyzed the prehospital interventions performed on patients with MPDS determinants for breathing problems, chest pain, unknown problem (man down), seizures, fainting (unconscious) and falls for transport status and interventions.
Methods:
We matched all prehospital patients in complaint-based categories for breathing problems, chest pain, unknown problem (man down), seizures, fainting (unconscious) and falls from January 1, 2004, to December 31, 2006, with their prehospital record. Calls were queried for the following prehospital interventions: Basic Life Support care only, intravenous line placement only, medication given, procedures or non-transport. We defined Advanced Life Support (ALS) interventions as the administration of a medication or a procedure.
Results:
Of the 77,394 MPDS calls during this period, 31,318 (40%) patients met inclusion criteria. Breathing problems made up 12.2%, chest pain 6%, unknown problem 1.4%, seizures 3%, falls 9% and unconscious/fainting 9% of the total number of MPDS calls. Patients with breathing problem had a low rate of procedures (0.7%) and cardiac arrest medications (1.6%) with 38% receiving some medication. Chest pain patients had a similar distribution; procedures (0.5%), cardiac arrest medication (1.5%) and any medication (64%). Unknown problem: procedures (1%), cardiac arrest medication (1.3%), any medication (18%). Patients with Seizures had a low rate of procedures (1.1%) and cardiac arrest medications (0.6%) with 20% receiving some medication. Fall patients had a lower rate of severe illness with more medication, mostly morphine: procedures (0.2%), cardiac arrest medication (0.2%), all medications (28%). Unconscious/fainting patients received the following interventions: procedures (0.3%), cardiac arrest medication (1.9%), all medications (32%). Few stepwise increases in the rate of procedures or medications were seen as determinants increased in acuity.
Conclusion:
Among these common MPDS complaint-based categories, the rates of advanced procedures and cardiac arrest medications were low. ALS medications were common in all categories and most determinants. Multiple determinants were rarely used and did not show higher rates of interventions with increasing acuity. Many MPDS determinants are of modest use to predict ALS intervention.
PMCID: PMC3088370  PMID: 21691468
21.  State of the Globe: Rabies is Still Rampant and Needs Action 
doi:10.4103/0974-777X.68523
PMCID: PMC2946672  PMID: 20927277
22.  Rabies in Foxes, Aegean Region, Turkey 
Emerging Infectious Diseases  2009;15(10):1620-1622.
At the end of the 1990s in the Aegean region of Turkey, rabies rapidly spread among foxes. This spread likely resulted from spillover infection from dogs and led to increased rabies cases among cattle. To control this outbreak, oral rabies vaccination of foxes has been used.
doi:10.3201/eid1510.090203
PMCID: PMC2866395  PMID: 19861056
Rabies; dog; fox; spillover; Turkey; viruses; dispatch
23.  Emerging Technologies for the Detection of Rabies Virus: Challenges and Hopes in the 21st Century 
The diagnosis of rabies is routinely based on clinical and epidemiological information, especially when exposures are reported in rabies-endemic countries. Diagnostic tests using conventional assays that appear to be negative, even when undertaken late in the disease and despite the clinical diagnosis, have a tendency, at times, to be unreliable. These tests are rarely optimal and entirely dependent on the nature and quality of the sample supplied. In the course of the past three decades, the application of molecular biology has aided in the development of tests that result in a more rapid detection of rabies virus. These tests enable viral strain identification from clinical specimens. Currently, there are a number of molecular tests that can be used to complement conventional tests in rabies diagnosis. Indeed the challenges in the 21st century for the development of rabies diagnostics are not of a technical nature; these tests are available now. The challenges in the 21st century for diagnostic test developers are two-fold: firstly, to achieve internationally accepted validation of a test that will then lead to its acceptance by organisations globally. Secondly, the areas of the world where such tests are needed are mainly in developing regions where financial and logistical barriers prevent their implementation. Although developing countries with a poor healthcare infrastructure recognise that molecular-based diagnostic assays will be unaffordable for routine use, the cost/benefit ratio should still be measured. Adoption of rapid and affordable rabies diagnostic tests for use in developing countries highlights the importance of sharing and transferring technology through laboratory twinning between the developed and the developing countries. Importantly for developing countries, the benefit of molecular methods as tools is the capability for a differential diagnosis of human diseases that present with similar clinical symptoms. Antemortem testing for human rabies is now possible using molecular techniques. These barriers are not insurmountable and it is our expectation that if such tests are accepted and implemented where they are most needed, they will provide substantial improvements for rabies diagnosis and surveillance. The advent of molecular biology and new technological initiatives that combine advances in biology with other disciplines will support the development of techniques capable of high throughput testing with a low turnaround time for rabies diagnosis.
doi:10.1371/journal.pntd.0000530
PMCID: PMC2745658  PMID: 19787037
24.  Draft Genome of the Filarial Nematode Parasite Brugia malayi 
Science (New York, N.Y.)  2007;317(5845):1756-1760.
Parasitic nematodes that cause elephantiasis and river blindness threaten hundreds of millions of people in the developing world. We have sequenced the ~90 megabase (Mb) genome of the human filarial parasite Brugia malayi and predict ~11,500 protein coding genes in 71 Mb of robustly assembled sequence. Comparative analysis with the free-living, model nematode Caenorhabditis elegans revealed that, despite these genes having maintained little conservation of local synteny during ~350 million years of evolution, they largely remain in linkage on chromosomal units. More than 100 conserved operons were identified. Analysis of the predicted proteome provides evidence for adaptations of B. malayi to niches in its human and vector hosts and insights into the molecular basis of a mutualistic relationship with its Wolbachia endosymbiont. These findings offer a foundation for rational drug design.
doi:10.1126/science.1145406
PMCID: PMC2613796  PMID: 17885136
25.  Reexamination of Human Rabies Case with Long Incubation, Australia 
Emerging Infectious Diseases  2008;14(12):1950-1951.
doi:10.3201/eid1412.080944
PMCID: PMC2634648  PMID: 19046531
rabies incubation period; Australia; letter

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