Towards the understanding of microRNA and environmental factor interactions and their relationships to human diseases

Increasing studies have shown that the interactions between microRNAs (miRNAs) and environmental factors (EFs) play critical roles in determining phenotypes and diseases. In this study, we revealed a number of important biological insights by analyzing and modeling of miRNA-EF interactions and their relationships with human diseases. We demonstrated that the miRNA signatures of EFs could provide new information on EFs. More importantly, we quantitatively showed that the miRNA signatures of drug/radiation could be used as indicators for evaluating the results of cancer treatments. Finally, we developed a computational model that could efficiently identify the possible relationship between EF and human diseases. Meanwhile, we provided a website (http://cmbi.hsc.pku.edu.cn/miren) for the main results of this study. This study elucidates the mechanisms of EFs, presents a framework for predicting the results of cancer treatments, and develops a model that illustrates the relationships between EFs and human diseases

Health risk behaviours among adolescents in the English-speaking Caribbean: a review

<p>Abstract</p> <p>Background</p> <p>The aim of this paper was to review and summarize research on prevalence of health risk behaviours, their outcomes as well as risk and protective factors among adolescents in the English-speaking Caribbean.</p> <p>Methods</p> <p>Searching of online databases and the World Wide Web as well as hand searching of the <it>West Indian Medical Journal </it>were conducted. Papers on research done on adolescents aged 10 – 19 years old and published during the period 1980 – 2005 were included.</p> <p>Results</p> <p>Ninety-five relevant papers were located. Five papers were published in the 1980s, 47 in the 1990s, and from 2000–2005, 43 papers. Health risk behaviours and outcomes were divided into seven themes. Prevalence data obtained for these, included lifetime prevalence of <b>substance use</b>: cigarettes-24% and marijuana-17%; <b>high risk sexual behaviour</b>: initiation of sexual activity ≤ 10 years old-19% and those having more than six partners-19%; <b>teenage pregnancy</b>: teens account for 15–20% of all pregnancies and one-fifth of these teens were in their second pregnancy; <b>Sexually-Transmitted Infections (STIs)</b>: population prevalence of gonorrhoea and/or chlamydia in 18–21 year-olds was 26%; <b>mental health</b>: severe depression in the adolescent age group was 9%, and attempted suicide-12%; <b>violence and juvenile delinquency</b>: carrying a weapon to school in the last 30 days-10% and almost always wanting to kill or injure someone-5%; <b>eating disorders and obesity</b>: overweight-11%, and obesity-7%. Many of the risk behaviours in adolescents were shown to be related to the adolescent's family of origin, home environment and parent-child relationships. Also, the protective effects of family and school connectedness as well as increased religiosity noted in studies from the United States were also applicable in the Caribbean.</p> <p>Conclusion</p> <p>There is a substantial body of literature on Caribbean adolescents documenting prevalence and correlates of health risk behaviours. Future research should emphasize the designing and testing of interventions to alleviate this burden.</p

The Immunomodulatory Effect of Antibiotics on the Secretion of Tumour Necrosis Factor Alpha by Peripheral Blood Mononuclear Cells in Response to Stenotrophomonas maltophilia Stimulation

Some antibiotics have been shown to modify the host immune response. Infection with Stenotrophomonas maltophilia, is often difficult to treat due to multiresistance to antibiotics. The authors examined the effect of four commonly used antimicrobial agents (ciprofloxacin, ceftazidime, cotrimoxazole and piperacillin-tazobactam) on tumour necrosis factor alpha (TNF α) production by human peripheral blood mononuclear cells (PBMC) stimulated with heat-killed S maltophilia. Cotrimoxazole was the only antibiotic that suppressed TNF αsecretion at clinically achievable concentrations. This may explain its use with good effect in the treatment of S maltophilia infections. However at supratherapeutic concentrations, ceftazidime and ciprofloxacin, but not piperacillin-tazobactam, also inhibited significantly the production of TNF α. Cotrimoxazole, in addition to its antimicrobial effect against S maltophilia, has an immunomodulatory effect on peripheral blood mononuclear cells stimulated by S maltophilia. "Efecto Inmunomodulatorio de los Antibióticos Sobre la Secreción del Factor de Necrosis Tumoral Alfa por Células Sanguíneas Mononucleares Periféricas en Respuesta a la Estimulación de Stenotrophomonas Maltophilia" RESUMEN Algunos antibióticos han mostrado ser capaces de modificar la respuesta inmune del huésped. Las infecciones con Stenotrophomonas maltophilia – un patógeno emergente – son difíciles de tratar debido a su multiresistencia a los antibióticos. Examinamos el efecto de cuatro agentes antimicrobianos comúnmente usados (ciprofloxacina, ceftazidima, cotrimoxazol, y piperacilina-tazobactam) sobre la producción del factor de necrosis tumoral alfa (FNT α) por las células sanguíneas mononucleares periféricas humanas (PBMC) estimuladas con S maltophilia inactivadas mediante calor. El cotrimoxazol – en concentraciones clínicamente posibles – fue el único antibiótico que eliminó la secreción FNT α. Esto puede explicar su uso efectivo en el tratamiento de las infecciones por S maltophilia. Sin embargo, en concentraciones supraterapéuticas, la ceftazidima y la cipro-floxacina – pero no la piperacilina- tazobactam – también inhibieron significativamente la producción de FNT α. El cotrimoxazol, además de su efecto antimicrobiano contra S maltophilia, tiene un efecto inmuno-modulatorio sobre las células sanguíneas mononucleares periféricas estimuladas por S maltophilia

"Epidemiology of Coagulase-Negative Staphylococci Isolated from Clinical Blood Specimens at the University Hospital of the West Indies"

The prevalence and significance of coagulase negative staphylococci (CoNS) isolated from blood cultures at the University Hospital of the West Indies (UHWI) during a six-month period were investigated. Standard and automated microbiological procedures were used to process 3001 blood culture specimens received from 2363 patients and 658 (21.9%) of the blood cultures yielded 854 bacterial isolates. The highest prevalence of positive blood cultures (60%) and the lowest prevalence of blood isolates of CoNS (12%) were found in the intensive care unit (ICU). The blood isolates of CoNS were most frequent in the surgical wards (13%) and lowest in obstetrics and gynaecology (2%). High rates of resistance to methicillin, other anti-staphylococcal penicillins, and cephalosporins used in the treatment of CoNS were observed. All blood isolates of CoNS (100%) were susceptible to vancomycin. In conclusion, the results show that coagulase-negative staphylococci are the most prevalent bacterial isolates in blood cultures at the UHWI occurring mostly as contaminants. The practice of proper venepuncture and hand-washing techniques by medical staff are recommended to facilitate appropriate antibiotic usage. "Epidemiología de los Estafilococos Coagulasa Negativos Aislados de Especímenes Clínicos de Sangre en el Hospital Universitario de West Indies" RESUMEN Se investigó la prevalencia e importancia de los estafilococos coagulasa negativos (ECoN) aislados de cultivos de sangre en el Hospital Universitario de West Indies (HUWI) por un período de seis meses. Se utilizaron procedimientos microbiológicos estándar y automatizados para procesas 3001 cultivos de sangre recibidos de 2363 pacientes y 658 (21.9%) de los cultivos dieron 854 aislados bacterianos. La más alta prevalencia de cultivos de sangre positivos (60%) y la más baja prevalencia de aislados de ECoN (12%) se encontraron en la Unidad de Cuidados Intensivos (UCI). Los aislados de sangre de ECoN fueron más frecuentes en las salas de cirugía (13%) y más bajos en las de obstetricia y ginecología (2%). Se observaron altas tasas de resistencia a la meticilina, así como a otras penicilinas antiestafilocócicas y cefalosporinas usadas en el tratamiento de ECoN. Todos los aislados de sangre de ECoN (100%) fueron susceptibles a la vancomicina. En conclusión, los resultados muestran que los estafilococos coagulasa negativos son los aislados bacterianos más prevalentes en cultivos de sangre en el HUWI, presentándose en la mayor parte de los casos como contaminantes. Se recomienda la práctica de técnicas adecuadas de venepuntura y lavado de manos por parte del personal médico a fin de facilitar un uso antibiótico correcto