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941.
942.
943.
Ronald D. Snyder Patrick A. Holt Jon M. Maguire John O. Trent 《Drug and chemical toxicology》2015,38(2):212-219
Fifty two steroids and 9 Vitamin D analogs were docked into ten crystallographically-defined DNA dinucleotide sites and two human topoisomerase II ATP binding sites using two computational programs, Autodock and Surflex. It is shown that both steroids and Vitamin D analogs exhibit a propensity for non-covalent intercalative binding to DNA. A higher predicted binding affinity was found, however, for steroids and the ATP binding site of topoisomerase; in fact these drugs exhibited among the highest topo II binding observed in over 1370 docked drugs. These findings along with genotoxicity data from 26 additional steroids not subjected to docking analysis, support a mechanism wherein the long known, but poorly understood, clastogenicity of steroids may be attributable to inhibition of topoisomerase. A “proof of principle” experiment with dexamethasone demonstrated this to be the likely mechanism of clastogenicity of, at least, this steroid. The generality of this proposed mechanism of genotoxicity across the steroids and vitamin-D analogs is discussed. 相似文献
944.
945.
Ibraheem Rasheeedah Oladele Patrick AbdulAzeez Abdullateef Abdulkadri Mohammed Katibi Sherifat Ibraheem Gbadebo 《Ethiopian journal of health sciences》2015,25(3):279-282
Background
Mucopolysaccharidosis type II (Hunter''s syndrome) is an X-linked chromosomal storage disorder due to deficiency of the lysosomal enzyme iduronate-2-sulfatase with patients rarely living till adulthood. Failure to identify patients early could contribute to an increased morbidity as identified in this case report.Case Details
An eight year old patient with Hunter''s syndrome identified five years after disease onset with severe cardiovascular complications exemplifies the challenges faced in resource-limited countries towards making diagnosis and treatment of rare conditions. Elevated urinary glycosaminoglycans levels or a strong clinical suspicion of Hunter''s syndrome, as identified in the index case, is a prerequisite for enzyme activity testing. Urinary mucopolysaccharide(MPS) level was 69.6mg/mmol(normal range is 0.0 – 11.6mg/mmol), and the confirming MPS electrophoresis analysis showed elevated heparan sulphate in the urine sample. Enzyme activity testing, with absent or very low iduronate-2-sulfatase activity, is diagnostic. However, the scarce availability and high cost of these tests is another constraint in making a diagnosis.Conclusion
Identification and management of mucopolysaccharidosis type II pose a problem in resource-constrained countries due to late presentation, lack of facility for diagnosis and treatment, cost and expertise required for the management. 相似文献946.
M. Allison Arwady Luke Bawo Jennifer C. Hunter Moses Massaquoi Almea Matanock Bernice Dahn Patrick Ayscue Tolbert Nyenswah Joseph D. Forrester Lisa E. Hensley Benjamin Monroe Randal J. Schoepp Tai-Ho Chen Kurt E. Schaecher Thomas George Edward Rouse Ilana J. Schafer Satish K. Pillai Kevin M. De Cock 《Emerging infectious diseases》2015,21(4):578-584
Over the span of a few weeks during July and August 2014, events in West Africa changed perceptions of Ebola virus disease (EVD) from an exotic tropical disease to a priority for global health security. We describe observations during that time of a field team from the Centers for Disease Control and Prevention and personnel of the Liberian Ministry of Health and Social Welfare. We outline the early epidemiology of EVD within Liberia, including the practical limitations on surveillance and the effect on the country’s health care system, such as infections among health care workers. During this time, priorities included strengthening EVD surveillance; establishing safe settings for EVD patient care (and considering alternative isolation and care models when Ebola Treatment Units were overwhelmed); improving infection control practices; establishing an incident management system; and working with Liberian airport authorities to implement EVD screening of departing passengers. 相似文献
947.
948.
Hoang Vu Tran Linh-Vi N. Le Lisa Grazina Johnston Patrick Nadol Anh Van Do Ha Thi Thanh Tran Tuan Anh Nguyen 《Journal of urban health》2015,92(4):744-757
Accurate measurements of HIV prevalence and associated risk factors among hidden and high-risk groups are vital for program planning and implementation. However, only two sampling methods are purported to provide representative estimates for populations without sampling frames: time-location sampling (TLS) and respondent-driven sampling (RDS). Each method is subject to potential biases and questionable reliability. In this paper, we evaluate surveys designed to estimate HIV prevalence and associated risk factors among people who inject drugs (PWID) sampled through TLS versus RDS. In 2012, males aged ≥16 years who reported injecting drugs in the previous month and living in Haiphong, Vietnam, were sampled using TLS or RDS. Data from each survey were analyzed to compare HIV prevalence, related risk factors, socio-demographic characteristics, refusal estimates, and time and expenditures for field implementation. TLS (n = 432) and RDS (n = 415) produced similarly high estimates for HIV prevalence. Significantly lower proportions of PWID sampled through RDS received methadone treatment or met an outreach worker. Refusal estimates were lower for TLS than for RDS. Total expenditures per sample collected and number of person-days of staff effort were higher for TLS than for RDS. Both survey methods were successful in recruiting a diverse sample of PWID in Haiphong. In Vietnam, surveys of PWID are conducted throughout the country; although the refusal estimate was calculated to be much higher for RDS than TLS, RDS in Haiphong appeared to sample PWID with less exposure to services and required fewer financial and staff resources compared with TLS. 相似文献
949.
Susanna K.P. Lau Alan K.L. Wu Jade L.L. Teng Herman Tse Shirly O.T. Curreem Stephen K.W. Tsui Yi Huang Jonathan H.K. Chen Rodney A. Lee Kwok-Yung Yuen Patrick C.Y. Woo 《Emerging infectious diseases》2015,21(2):232-241
Elizabethkingia anophelis, recently discovered from mosquito gut, is an emerging bacterium associated with neonatal meningitis and nosocomial outbreaks. However, its transmission route remains unknown. We use rapid genome sequencing to investigate 3 cases of E. anophelis sepsis involving 2 neonates who had meningitis and 1 neonate’s mother who had chorioamnionitis. Comparative genomics revealed evidence for perinatal vertical transmission from a mother to her neonate; the 2 isolates from these patients, HKU37 and HKU38, shared essentially identical genome sequences. In contrast, the strain from another neonate (HKU36) was genetically divergent, showing only 78.6% genome sequence identity to HKU37 and HKU38, thus excluding a clonal outbreak. Comparison to genomes from mosquito strains revealed potential metabolic adaptations in E. anophelis under different environments. Maternal infection, not mosquitoes, is most likely the source of neonatal E. anophelis infections. Our findings highlight the power of genome sequencing in gaining rapid insights on transmission and pathogenesis of emerging pathogens. 相似文献
950.
The development and initial validation of a questionnaire to measure help‐seeking behaviour in patients with new onset rheumatoid arthritis 下载免费PDF全文
Rebecca J. Stack BSc MBPsS MSc PhD Christian D. Mallen BMBS FRCGP PhD Chris Deighton BMedSci MD FRCP Patrick Kiely BSc MBBS PhD FRCP Karen L. Shaw BSc MBPsS PgCert PhD Alison Booth RN MSc Kanta Kumar RN MSc Susan Thomas BA MA Ian Rowan Rob Horne BSc MSc PhD MRPharm Peter Nightingale BSc PhD Sandy Herron‐Marx RGN DPSN BA PGcap PhD Clare Jinks BA MPhil PhD Karim Raza FRCP PhD 《Health expectations》2015,18(6):2340-2355