1,724 research outputs found
Rapid identification of mutations in GJC2 in primary lymphoedema using whole exome sequencing combined with linkage analysis with delineation of the phenotype.
Background: Primary lymphoedema describes a chronic, frequently progressive, failure of lymphatic drainage. This disorder is frequently genetic in origin, and a multigenerational family in which eight individuals developed postnatal lymphoedema of all four limbs was ascertained from the joint Lymphoedema/Genetic clinic at St George's Hospital.
Methods: Linkage analysis was used to determine a locus, and exome sequencing was employed to look for causative variants.
Results: Linkage analysis revealed cosegregation of a 16.1 Mb haplotype on chromosome 1q42 that contained 173 known or predicted genes. Whole exome sequencing in a single affected individual was undertaken, and the search for the causative variant was focused to within the linkage interval. This approach revealed two novel non-synonymous single nucleotide substitutions within the chromosome 1 locus, in NVL and GJC2. NVL and GJC2 were sequenced in an additional cohort of individuals with a similar phenotype and non-synonymous variants were found in GJC2 in four additional families.
Conclusion: This report demonstrates the power of exome sequencing efficiently applied to a traditional positional cloning pipeline in disease gene discovery, and suggests that the phenotype produced by GJC2 mutations is predominantly one of 4 limb lymphoedema
Bacteriophage MS2 displays unreported capsid variability assembling TÂ =Â 4 and mixed capsids
Bacteriophage MS2 is a positive-sense, single-stranded RNA virus encapsulated in an asymmetric TÂ =Â 3 pseudo-icosahedral capsid. It infects Escherichia coli through the F-pilus, which it binds through a maturation protein incorporated into its capsid. Cryogenic electron microscopy has previously shown that its genome is highly ordered within virions, and that it regulates the assembly process of the capsid. In this study we have assembled recombinant MS2 capsids with non-genomic RNA containing the capsid incorporation sequence, and investigated the structures formed, revealing that TÂ =Â 3, TÂ =Â 4 and mixed capsids between these two triangulation numbers are generated, and resolving structures of TÂ =Â 3 and TÂ =Â 4 capsids to 4Â Ă
and 6Â Ă
respectively. We conclude that the basic MS2 capsid can form a mix of TÂ =Â 3 and TÂ =Â 4 structures, supporting a role for the ordered genome in favouring the formation of functional TÂ =Â 3 virions
Correlates of substance abuse treatment completion among disadvantaged communities in Cape Town, South Africa
BACKGROUND: Completion of substance abuse treatment is a proximal indicator of positive treatment outcomes. To design interventions to improve outcomes, it is therefore important to unpack the factors contributing to treatment completion. To date, substance abuse research has not examined the factors associated with treatment completion among poor, disadvantaged communities in developing countries. This study aimed to address this gap by exploring client-level factors associated with treatment completion among poor communities in South Africa. METHODS: Secondary data analysis was conducted on cross-sectional survey data collected from 434 persons residing in poor communities in Cape Town, South Africa who had accessed substance abuse treatment in 2006. RESULTS: Multiple regression analyses revealed that therapeutic alliance, treatment perceptions, abstinence-specific social support, and depression were significant partial predictors of treatment completion. CONCLUSIONS: Findings suggest that treatment completion rates of individuals from poor South African communities can be enhanced by i) improving perceptions of substance abuse treatment through introducing quality improvement initiatives into substance abuse services, ii) strengthening clients' abstinence-oriented social networks and, iii) strengthening the counselor-client therapeutic alliance
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Potential migration and subjective well-being in Europe
By examining the preferences over migration destinations of those revealing a desire to permanently leave their country, this paper provides new evidence on the relevance of subjective measures for cross country comparisons. While hard statistics such as GDP per capita and unemployment rates are commonly used to measure a countryâs success, this analysis reveals that peopleâs preferences over alternative migration
destinations are better explained by average levels of life satisfaction in the destination country. Aggregated measures of subjective well-being are, therefore, useful for international comparisons as they better reflect what makes some countries more attractive than others
Risk factors for high anti-HHV-8 antibody titers (â„1:51,200) in black, HIV-1 negative South African cancer patients: a case control study
Background: Infection with human herpesvirus 8 (HHV-8) is the necessary causal agent in the
development of Kaposi's sarcoma (KS). Infection with HIV-1, male gender and older age all increase
risk for KS. However, the geographic distribution of HHV-8 and KS both prior to the HIV/AIDS
epidemic and with HIV/AIDS suggest the presence of an additional co-factor in the development of
KS.
Methods: Between January 1994 and October 1997, we interviewed 2576 black in-patients with
cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1
and HHV-8 and the study was restricted to 2191 HIV-1 negative patients. Antibodies against the
latent nuclear antigen of HHV-8 encoded by orf73 were detected with an indirect
immunofluorescence assay. We examined the relationship between high anti-HHV-8 antibody
titers (â„1:51,200) and sociodemographic and behavioral factors using unconditional logistic
regression models. Variables that were significant at p = 0.10 were included in multivariate analysis.
Results: Of the 2191 HIV-1 negative patients who did not have Kaposi's sarcoma, 854 (39.0%)
were positive for antibodies against HHV-8 according to the immunofluorescent assay. Among
those seropositive for HHV-8, 530 (62.1%) had low titers (1:200), 227 (26.6%) had medium titers
(1:51,200) and 97 (11.4%) had highest titers (1:204,800). Among the 2191 HIV-1 negative patients,
the prevalence of high anti-HHV-8 antibody titers (â„1:51,200) was independently associated with
increasing age (ptrend = 0.04), having a marital status of separated or divorced (p = 0.003), using
wood, coal or charcoal as fuel for cooking 20 years ago instead of electricity (p = 0.02) and
consuming traditional maize beer more than one time a week (p = 0.02; p-trend for increasing
consumption = 0.05) although this may be due to chance given the large number of predictors
considered in this analysis.
Conclusions: Among HIV-negative subjects, patients with high anti-HHV-8 antibody titers are
characterized by older age. Other associations that may be factors in the development of high anti-
HHV-8 titers include exposure to poverty or a low socioeconomic status environment and
consumption of traditional maize beer. The relationship between these variables and high anti-
HHV-8 titers requires further, prospective study
The first legal mortgagor: a consumer without adequate protection?
This article contends that the UK governmentâs attempt to create a well-functioning consumer credit market will be undermined if it fails to reform the private law framework relating to the first legal mortgage. Such agreements are governed by two distinct regulatory regimes that are founded upon very different conceptions of the mortgagor. The first, the regulation of financial services overseen by the Financial Conduct Authority, derives from public law and is founded upon a conception of the mortgagor as âconsumerâ. The other is land law, private law regulation implemented by the judiciary and underpinned by a conception of the mortgagor as âlandownerâ. Evidence suggests that the operation of these two regimes prevents mortgagors from receiving fair and consistent treatment. The current reform of financial services regulation therefore will change only one part of this governance regime and will leave mortgagors heavily reliant upon a regulator that still has to prove itself. What this article argues is that reform of the rules of private law must also be undertaken with the aim of initiating a paradigm shift in the conception of the mortgagor from âlandownerâ to âconsumerâ. Cultural shifts of this kind take time but the hope is that this conceptual transformation will occur in time to deter the predicted rise in mortgage possessions
Description et évaluation d'un réseau d'épidémiosurveillance des pathologies porcines mis en place dans un district du Nord Vietnam
Background and objective: Early menarche is increasing in prevalence worldwide, prompting clinical andpublic health interest on its links with pulmonary function. We aimed to investigate the relationship betweenearly menarche and lung function in middle age.Methods: The population-based Tasmanian LongitudinalHealth Study (born 1961; n = 8583), was initiated in 1968.The 5th Decade follow-up data (mean age: 45 years)included age at menarche and complex lung function testing. The 6th Decade follow-up (age: 53 years) repeated spirometry and gas transfer factor. Multiple linear regressionand mediation analyses were performed to determine theassociation between age at menarche and adult lung function and investigate biological pathways, including the proportion mediated by adult-attained height.Results: Girls reporting an early menarche (Conclusion:Early menarche was associated withreduced adult lung function. This is the first study toinvestigate post-BD outcomes and quantify the partialrole of adult height in this association
Habitat filtering determines spatial variation of macroinvertebrate community traits in northern headwater streams
Although our knowledge of the spatial distribution of stream organisms has been increasing rapidly in the last decades, there is still little consensus about trait-based variability of macroinvertebrate communities within and between catchments in near-pristine systems. Our aim was to examine the taxonomic and trait based stability vs. variability of stream macroinvertebrates in three high-latitude catchments in Finland. The collected taxa were assigned to unique trait combinations (UTCs) using biological traits. We found that only a single or a highly limited number of taxa formed a single UTC, suggesting a low degree of redundancy. Our analyses revealed significant differences in the environmental conditions of the streams among the three catchments. Linear models, rarefaction curves and beta-diversity measures showed that the catchments differed in both alpha and beta diversity. Taxon- and trait-based multivariate analyses also indicated that the three catchments were significantly different in terms of macroinvertebrate communities. All these findings suggest that habitat filtering, i.e., environmental differences among catchments, determines the variability of macroinvertebrate communities, thereby contributing to the significant biological differences among the catchments. The main implications of our study is that the sensitivity of trait-based analyses to natural environmental variation should be carefully incorporated in the assessment of environmental degradation, and that further studies are needed for a deeper understanding of trait-based community patterns across near-pristine streams
The Mechanisms of Codon Reassignments in Mitochondrial Genetic Codes
Many cases of non-standard genetic codes are known in mitochondrial genomes.
We carry out analysis of phylogeny and codon usage of organisms for which the
complete mitochondrial genome is available, and we determine the most likely
mechanism for codon reassignment in each case. Reassignment events can be
classified according to the gain-loss framework. The gain represents the
appearance of a new tRNA for the reassigned codon or the change of an existing
tRNA such that it gains the ability to pair with the codon. The loss represents
the deletion of a tRNA or the change in a tRNA so that it no longer translates
the codon. One possible mechanism is Codon Disappearance, where the codon
disappears from the genome prior to the gain and loss events. In the
alternative mechanisms the codon does not disappear. In the Unassigned Codon
mechanism, the loss occurs first, whereas in the Ambiguous Intermediate
mechanism, the gain occurs first. Codon usage analysis gives clear evidence of
cases where the codon disappeared at the point of the reassignment and also
cases where it did not disappear. Codon disappearance is the probable
explanation for stop to sense reassignments and a small number of reassignments
of sense codons. However, the majority of sense to sense reassignments cannot
be explained by codon disappearance. In the latter cases, by analysis of the
presence or absence of tRNAs in the genome and of the changes in tRNA
sequences, it is sometimes possible to distinguish between the Unassigned Codon
and Ambiguous Intermediate mechanisms. We emphasize that not all reassignments
follow the same scenario and that it is necessary to consider the details of
each case carefully.Comment: 53 pages (45 pages, including 4 figures + 8 pages of supplementary
information). To appear in J.Mol.Evo
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