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Multilocus sequence typing of total-genome-sequenced bacteria 总被引:1,自引:0,他引:1
Larsen MV Cosentino S Rasmussen S Friis C Hasman H Marvig RL Jelsbak L Sicheritz-Pontén T Ussery DW Aarestrup FM Lund O 《Journal of clinical microbiology》2012,50(4):1355-1361
Accurate strain identification is essential for anyone working with bacteria. For many species, multilocus sequence typing (MLST) is considered the "gold standard" of typing, but it is traditionally performed in an expensive and time-consuming manner. As the costs of whole-genome sequencing (WGS) continue to decline, it becomes increasingly available to scientists and routine diagnostic laboratories. Currently, the cost is below that of traditional MLST. The new challenges will be how to extract the relevant information from the large amount of data so as to allow for comparison over time and between laboratories. Ideally, this information should also allow for comparison to historical data. We developed a Web-based method for MLST of 66 bacterial species based on WGS data. As input, the method uses short sequence reads from four sequencing platforms or preassembled genomes. Updates from the MLST databases are downloaded monthly, and the best-matching MLST alleles of the specified MLST scheme are found using a BLAST-based ranking method. The sequence type is then determined by the combination of alleles identified. The method was tested on preassembled genomes from 336 isolates covering 56 MLST schemes, on short sequence reads from 387 isolates covering 10 schemes, and on a small test set of short sequence reads from 29 isolates for which the sequence type had been determined by traditional methods. The method presented here enables investigators to determine the sequence types of their isolates on the basis of WGS data. This method is publicly available at www.cbs.dtu.dk/services/MLST. 相似文献
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Nina Roswall Signe B. Larsen Søren Friis Malene Outzen Anja Olsen Jane Christensen Lars O. Dragsted Anne Tjønneland 《Cancer causes & control : CCC》2013,24(6):1129-1135
Purpose
Micronutrients may protect against prostate cancer. However, few studies have had high-quality assessment of both dietary and supplemental consumption of micronutrients, rendering possible different source-specific effects difficult to discern. This study evaluates associations between intake of vitamin C, E, folate, and beta-carotene and prostate cancer risk, focusing on possible different effects of dietary, supplemental, or total intake and on potential effect modification by alcohol intake and BMI.Methods
Danish prospective cohort study of 26,856 men aged 50–64 years with questionnaire-based information on diet, supplements, and lifestyle. Hazard ratios (HRs) for prostate cancer associated with micronutrient intake were calculated using Cox proportional hazard analyses.Results
During follow-up (1993–2010), 1,571 prostate cancer cases were identified. Supplemental folic acid was inversely associated with prostate cancer risk, notably on a continuous scale [HR 0.88 (95 % CI 0.79–0.98) per 100 μg increase/day]. The risk reduction was largely confined to non-aggressive tumors [HR 0.71 (0.55–0.93) per 100 μg increase/day]. No influence on prostate cancer risk was observed for dietary folate or for the other studied micronutrients, regardless of source. We found no significant effect modification by alcohol intake and BMI in relation to any micronutrient.Conclusion
Our study may indicate an inverse association between folic acid and prostate cancer; however, the inverse association was confined to supplemental folic acid and non-aggressive prostate cancer and may thus be a chance finding. Further studies are warranted to evaluate our findings. 相似文献996.
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Dirk L. Christensen Francis O. Orech Michael N. Mungai Torben Larsen Henrik Friis Jens Aagaard-Hansen 《International journal of food sciences and nutrition》2013,64(3-4):198-203
Primary objective To determine the iron, zinc, and calcium content in different insects commonly eaten among the Luo of Kenya.Research design A cross-sectional design was chosen for the study in order to determine the insects eaten and their mineral content during a specific season.Methods and procedures Five different insect species were identified and collected with the help of local informants in the Nyang'oma sublocation of the Bondo district in western Kenya, and were analysed for iron, zinc and calcium contents.Main outcomes and results The iron content ranged from 18 to 1562 mg/100 g dry matter, the zinc content from 8 to 25 mg/100 g, and the calcium content from 33 to 341 mg/100 g in five different insects, onyoso mammon (ant), oyala (termite), ogawo (termite), agaor (termite), onjiri mammon (cricket).Conclusions Insect eating could prove to be a valuable measure to combat, especially, iron and zinc deficiency in developing countries. 相似文献
999.
Abrar M Tamboli Rukhsana A Rub Pinaki Ghosh SL Bodhankar 《Asian Pacific Journal of Tropical Biomedicine》2012,2(7):537-542
Objective
To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid (GABA) in brain of mice in Pentylenetetrazol (PTZ) seizure models.Methods
The anticonvulsant activity of the isolated lobeline (5, 10, 20 and 30 mg/kg, i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lobeline on brain GABA level in seizures induced by PTZ. Diazepam was used as reference anticonvulsant drugs for comparison.Results
Isolated lobeline (10, 20 and 30 mg/kg, i.p.) significantly delayed and antagonized (P < 0.050–0.001) the onset of PTZ-induced seizures. It also antagonized strychnine induced seizures. The mortality was also prevented in the test group of animals. In biochemical evaluation, isolated lobeline (5, 10 and 20 mg/kg, i.p.) significantly increased the brain GABA level. And at dose of 30 mg/kg GABA level showed slight decrease in PTZ model.Conclusions
In our findings, isolated lobeline (20mg/kg) exhibited potent anticonvulsant activity against PTZ induced seizures. Also a biochemical evaluation suggested significant increase in barain GABA level at 20 mg/kg i.p. of isolated lobeline. Hence, we may propose that lobeline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism. 相似文献1000.
Jónsdóttir H Friis S Horne R Pettersen KI Reikvam A Andreassen OA 《Acta psychiatrica Scandinavica》2009,119(1):78-84
Objective: To determine if the Beliefs about Medicines Questionnaire (BMQ) has satisfactory psychometric properties in patients with severe mental disorders and if their scores differ from those of patients with severe medical disorders. To investigate if the scores are related to medication adherence. Method: Two hundred and eighty psychiatric patients completed the BMQ and reported how much of their medication they had taken the past week. Serum concentrations of medications were analyzed. BMQ scores were compared with those of patients with chronic medical disorders. Results: Cronbach’s alpha was satisfactory for all subscales. The psychiatric group scored lower on the necessity of taking medication than the medical group. Non‐adherent patients felt medication to be less necessary and were more concerned about it than adherent patients. The necessity subscale predicted adherence fairly well. Conclusion: The BMQ has satisfactory psychometric properties for use in patients with severe mental disorders. The constructs measured by the BMQ are related to adherence in these patients. 相似文献