350 research outputs found
Sustaining large-scale infrastructure to promote pre-competitive biomedical research: lessons from mouse genomics.
Bio-repositories and databases for biomedical research enable the efficient community-wide sharing of reagents and data. These archives play an increasingly prominent role in the generation and dissemination of bioresources and data essential for fundamental and translational research. Evidence suggests, however, that current funding and governance models, generally short-term and nationally focused, do not adequately support the role of archives in long-term, transnational endeavours to make and share high-impact resources. Our qualitative case study of the International Knockout Mouse Consortium and the International Mouse Phenotyping Consortium examines new governance mechanisms for archive sustainability. Funders and archive managers highlight in interviews that archives need stable public funding and new revenue-generation models to be sustainable. Sustainability also requires archives, journal publishers, and funders to implement appropriate incentives, associated metrics, and enforcement mechanisms to ensure that researchers use archives to deposit reagents and data to make them publicly accessible for academia and industry alike.This work was supported by the NorCOMM2 Project funded by Genome Canada [AM and TB]; the Ontario Genome Institute [TB]; and the Canadian Stem Cell Network [TB]. The authors have no competing interests. The funders of the study exerted no influence on the design and conduct of the study or on the analysis and presentation of results. We thank Lesley Dacks, Lorna Skaley and Dr Ann Flenniken for research support and project coordination. We thank the participants who took time out of their busy schedules for interviews and to review our analyses. We thank Dr Farah Huzair for feedback and the IMPC leadership for permission to use a modified version (Figure 1) of the Consortium's map of its global membership (http://www.mousephenotype.org/about-impc/impc-members). We are grateful to Drs Andy Smith and John Hancock for advice on the ELIXIR funding and governance model.This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.nbt.2015.10.00
Antibacterial and antifungal evaluation of some chalcogen bearing ligands, their transition and nontransition metal complexes
Eight chalcogen bearing compounds, 3-(4-fluorophenyl telluro) propylamine (1), 3-(phenyl telluro)propylammonium acetate salt (2), 3-(phenyl telluro)propylacetamide (3) and α-(phenylseleno) acetic acid (4) (1-4 are ligands), [Ph2Sn(Cl).1](NO3 ) (5), [Ph3Sn.1](BPh4 ) (6), [ZnCl2 .2] (7) and [CdCl2.2] (8) (5-8 are complexes of 1 and 2) were synthesised and screened for antibacterial activity against Gram-positive bacterial strains of Staphylococcus aureus, Bacillus anthracis and the Gramnegative bacteria Escherchia coli. They were also tested for their antifungal activity against Candida tropicalis, Trichophyton rubrum and Asperegillus niger, by using the disk diffusion technique. Inhibition zones demonstrated that compounds 1–3 showed significant activity, due to the presence of N in the form of amine group however Compound 4 bearing an acidic group, shows higher activity against bacterial strains. Compounds 5–8 (having Sn, Zn and Cd in their framework) showed still higher activities, due to increase in the lipophilicity and easier penetration of the compounds into the outer cell wall of the microorganisms, which causes death due to cell membrane rupturing. Compounds 1–8 were most effective against E. coli (bacterial strains), as the cell wall of Gram-negative strains have thin outer lipid membrane, which is made up of lipopolysaccharides. These compounds showed slightly reduced antifungal activity, because the cell wall of fungi is made up of chitin, which is difficult to cross. It could be concluded, from the obtained results that the biological activity of compounds is essentially determined by the number and nature of the organic groups and central metal ion. The presence of NH2, COOH group as well as metal ion like Sn, Zn, Cd in the compounds leads to higher activity
Genetic variation in histidine rich proteins among Indian Plasmodium falciparum population: possible cause of variable sensitivity of malaria rapid diagnostic tests
BACKGROUND: Rapid diagnostic tests (RDTs) have revolutionized the diagnosis of malaria. Among the various factors affecting RDTs sensitivity is genetic variation of the antigen used. The genetic variation in PfHRP2 and PfHRP3 proteins was studied among the Indian Plasmodium falciparum isolates. METHODS: One hundred and forty isolates of P. falciparum were collected from six geographical regions of India. Target genes encoding PfHRP2 and PfHRP3 antigens were sequenced to study genetic polymorphism. Minimum detection limit giving a positive rapid diagnostic test was also determined. RESULTS: Extensive variations were observed in amino acid repeat types of PfHRP2 and PfHRP3. PfHRP2 exhibited more polymorphism than PfHRP3. Significant relation was observed between type 2 and type 7 repeats and RDT detection rate as higher number of these repeats showed better sensitivity with RDTs. CONCLUSION: The results provide insights into the genetic diversity of Pfhrp2 and Pfhrp3 genes among Indian P. falciparum population and its relation to RDT sensitivity
Development and evaluation of a real-time one step Reverse-Transcriptase PCR for quantitation of Chandipura Virus
<p>Abstract</p> <p>Background</p> <p>Chandipura virus (CHPV), a member of family <it>Rhabdoviridae </it>was attributed to an explosive outbreak of acute encephalitis in children in Andhra Pradesh, India in 2003 and a small outbreak among tribal children from Gujarat, Western India in 2004. The case-fatality rate ranged from 55–75%. Considering the rapid progression of the disease and high mortality, a highly sensitive method for quantifying CHPV RNA by real-time one step reverse transcriptase PCR (real-time one step RT-PCR) using TaqMan technology was developed for rapid diagnosis.</p> <p>Methods</p> <p>Primers and probe for P gene were designed and used to standardize real-time one step RT-PCR assay for CHPV RNA quantitation. Standard RNA was prepared by PCR amplification, TA cloning and run off transcription. The optimized real-time one step RT-PCR assay was compared with the diagnostic nested RT-PCR and different virus isolation systems [<it>in vivo </it>(mice) <it>in ovo </it>(eggs), <it>in vitro </it>(Vero E6, PS, RD and Sand fly cell line)] for the detection of CHPV. Sensitivity and specificity of real-time one step RT-PCR assay was evaluated with diagnostic nested RT-PCR, which is considered as a gold standard.</p> <p>Results</p> <p>Real-time one step RT-PCR was optimized using <it>in vitro </it>transcribed (IVT) RNA. Standard curve showed linear relationship for wide range of 10<sup>2</sup>-10<sup>10 </sup>(r<sup>2 </sup>= 0.99) with maximum Coefficient of variation (CV = 5.91%) for IVT RNA. The newly developed real-time RT-PCR was at par with nested RT-PCR in sensitivity and superior to cell lines and other living systems (embryonated eggs and infant mice) used for the isolation of the virus. Detection limit of real-time one step RT-PCR and nested RT-PCR was found to be 1.2 × 10<sup>0 </sup>PFU/ml. RD cells, sand fly cells, infant mice, and embryonated eggs showed almost equal sensitivity (1.2 × 10<sup>2 </sup>PFU/ml). Vero and PS cell-lines (1.2 × 10<sup>3 </sup>PFU/ml) were least sensitive to CHPV infection. Specificity of the assay was found to be 100% when RNA from other viruses or healthy individual was used.</p> <p>Conclusion</p> <p>On account of the high sensitivity, reproducibility and specificity, the assay can be used for the rapid detection and quantitation of CHPV RNA from clinical samples during epidemics and from endemic areas. The assay may also find application in screening of antiviral compounds, understanding of pathogenesis as well as evaluation of vaccine.</p
Prognostic indicators in adults hospitalized with falciparum malaria in Western Thailand.
Background: Severe malaria remains a major cause of death and morbidity amongst adults in the Asiatic tropics.
Methods: A retrospective analysis of the clinical and laboratory data of 988 adult patients, hospitalized with
Plasmodium falciparum malaria and prospectively recruited to malaria studies in western Thailand between 1986
and 2002, was performed to assess the factors associated with a fatal outcome. Different severity scores and
classifications for defining severe malaria were compared and, using multiple logistic regression, simple models for
predicting mortality developed.
Results: The proportion of patients fulfilling the WHO 2000 definition of severe malaria was 78.1%, and their mortality
was 10%. Mortality in patients given parenteral artesunate or artemether (16/317, 5%) was lower than in those given
parenteral quinine (59/442, 13%) (P < 0.001). Models using parameter sets based on WHO 1990, 2000 and Adapted AQ
criteria plus blood smear parasite-stage assessment gave the best mortality prediction. A malaria prognostic index (MPI), derived from the dataset using five clinical or laboratory variables gave similar prognostic accuracy.
Conclusions: The mortality of severe malaria in adults has fallen and the switch from quinine to artesunate has probably been an important contributor. Prognostic indices based on WHO 2000 definitions, and other simpler indices based on fewer variables, provide clinically useful predictions of outcome in Asian adults with severe malaria
Comparing De Novo Genome Assembly: The Long and Short of It
Recent advances in DNA sequencing technology and their focal role in Genome Wide Association Studies (GWAS) have rekindled a growing interest in the whole-genome sequence assembly (WGSA) problem, thereby, inundating the field with a plethora of new formalizations, algorithms, heuristics and implementations. And yet, scant attention has been paid to comparative assessments of these assemblers' quality and accuracy. No commonly accepted and standardized method for comparison exists yet. Even worse, widely used metrics to compare the assembled sequences emphasize only size, poorly capturing the contig quality and accuracy. This paper addresses these concerns: it highlights common anomalies in assembly accuracy through a rigorous study of several assemblers, compared under both standard metrics (N50, coverage, contig sizes, etc.) as well as a more comprehensive metric (Feature-Response Curves, FRC) that is introduced here; FRC transparently captures the trade-offs between contigs' quality against their sizes. For this purpose, most of the publicly available major sequence assemblers – both for low-coverage long (Sanger) and high-coverage short (Illumina) reads technologies – are compared. These assemblers are applied to microbial (Escherichia coli, Brucella, Wolbachia, Staphylococcus, Helicobacter) and partial human genome sequences (Chr. Y), using sequence reads of various read-lengths, coverages, accuracies, and with and without mate-pairs. It is hoped that, based on these evaluations, computational biologists will identify innovative sequence assembly paradigms, bioinformaticists will determine promising approaches for developing “next-generation” assemblers, and biotechnologists will formulate more meaningful design desiderata for sequencing technology platforms. A new software tool for computing the FRC metric has been developed and is available through the AMOS open-source consortium
First observations of separated atmospheric nu_mu and bar{nu-mu} events in the MINOS detector
The complete 5.4 kton MINOS far detector has been taking data since the beginning of August 2003 at a depth of 2070 meters water-equivalent in the Soudan mine, Minnesota. This paper presents the first MINOS observations of nuµ and [overline nu ]µ charged-current atmospheric neutrino interactions based on an exposure of 418 days. The ratio of upward- to downward-going events in the data is compared to the Monte Carlo expectation in the absence of neutrino oscillations, giving Rup/downdata/Rup/downMC=0.62-0.14+0.19(stat.)±0.02(sys.). An extended maximum likelihood analysis of the observed L/E distributions excludes the null hypothesis of no neutrino oscillations at the 98% confidence level. Using the curvature of the observed muons in the 1.3 T MINOS magnetic field nuµ and [overline nu ]µ interactions are separated. The ratio of [overline nu ]µ to nuµ events in the data is compared to the Monte Carlo expectation assuming neutrinos and antineutrinos oscillate in the same manner, giving R[overline nu ][sub mu]/nu[sub mu]data/R[overline nu ][sub mu]/nu[sub mu]MC=0.96-0.27+0.38(stat.)±0.15(sys.), where the errors are the statistical and systematic uncertainties. Although the statistics are limited, this is the first direct observation of atmospheric neutrino interactions separately for nuµ and [overline nu ]µ
A study of relationships between bone-related vitamins and minerals, related risk markers, and subsequent mortality in older British people: the National Diet and Nutrition Survey of People Aged 65 Years and Over
Follow-up of a British national survey of older people found that in men, all-cause mortality was predicted by baseline plasma concentrations of phosphorus, albumin, creatinine and alpha 1-antichymotrypsin, and food energy intake and in women by plasma alkaline phosphatase, creatinine, alpha 1-antichymotrypsin, 25-hydroxy-vitamin D (marginally), and phosphorus intake
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