DRUM Community: Maryland Institute for Applied Environmental Health

Residual DNA in Commercial Taq DNA polymerase as a Source of Interference with Immuno-PCR assay

2013-04-10T02:34:42Z

Title: Residual DNA in Commercial Taq DNA polymerase as a Source of Interference with Immuno-PCR assay Authors: Guag, Jake Abstract: Polymerase Chain Reaction (PCR) was developed for a broad range of purposes. As part of developing a very sensitive Immuno-quantitative PCR (iqPCR) assay, we attempted to reproduce two of the published papers, almost always experienced false-positive amplification. Based on personal communication from one of the authors, we suspected that impure reagents were responsible for the false-positive amplification. However, PCR can amplify a small number of DNA into enormous numbers of copies and the possibility of environmental contamination cannot be excluded. In this paper we show that our primers appeared to amplify residual DNA in the Taq DNA polymerase, and induced false-positive results. This finding is not in the published methods papers for iqPCR.

Maternal mercury exposure, season of conception and adverse birth outcomes in an urban immigrant community in New York City

2013-02-07T03:45:33Z

Title: Maternal mercury exposure, season of conception and adverse birth outcomes in an urban immigrant community in New York City Authors: Bashore, Cynthia Diana Jennings Abstract: Adverse birth outcomes such as preterm birth (PTB: < 37 weeks gestation) and low birthweight (LBW: <2500g) result in severe infant morbidity and mortality. In the United States, there are racial and ethnic differences in the prevalence of preterm birth and low birth weight. The focus of this study is to examine the association between frequency of maternal fish consumption during pregnancy, prenatal mercury exposure, and season of conception with preterm birth and low birth weight in a population of African-American, Caribbean and West Indian women in an urban immigrant community in New York City. The proportion of preterm births and low birth rates in this cohort of women was higher than reported in other studies of African-American and Caribbean births in New York City. There was no association between maternal urinary mercury or infant cord blood concentrations and either LBW or preterm birth. Infants conceived in winter (December, January, February) were at increased odds of low birthweight.

Self-medication with antibiotics for the treatment of menstrual symptoms in southwest Nigeria: a cross-sectional study

2013-01-11T03:32:47Z

Title: Self-medication with antibiotics for the treatment of menstrual symptoms in southwest Nigeria: a cross-sectional study Authors: Sapkota, Amy R; Coker, Morenike E; Rosenberg Goldstein, Rachel E; Atkinson, Nancy L; Sweet, Shauna J; Sopeju, Priscilla O; Ojo, Modupe T; Otivhia, Elizabeth; Ayepola, Olayemi O; Olajuyigbe, Olufunmiso O; Shireman, Laura; Pottinger, Paul S; Ojo, Kayode K Abstract: Background: Self-medication with antibiotics is an important factor contributing to the development of bacterial antibiotic resistance. The purpose of this study was to evaluate the prevalence of self-medication with antibiotics for the treatment of menstrual symptoms among university women in Southwest Nigeria. Methods: A cross-sectional survey was administered to female undergraduate and graduate students (n = 706) at four universities in Southwest Nigeria in 2008. The universities were selected by convenience and the study samples within each university were randomly selected cluster samples. The survey was self-administered and included questions pertaining to menstrual symptoms, analgesic and antibiotic use patterns, and demographics. Data were analyzed using descriptive statistics and logistic regression. Results: The response rate was 95.4%. Eighty-six percent (95% CI: 83-88%) of participants experienced menstrual symptoms, and 39% (95% CI: 36-43%) reported using analgesics to treat them. Overall, 24% (95% CI: 21-27%) of participants reported self-medicated use of antibiotics to treat the following menstrual symptoms: cramps, bloating, heavy bleeding, headaches, pimples/acne, moodiness, tender breasts, backache, joint and muscle pain. Factors associated with this usage were: lower levels of education (Odds Ratio (OR): 2.8, 95% CI: 1.1-7.1, p-value: 0.03); nonscience major (OR: 1.58, 95% CI: 1.03-2.50, p-value: 0.04); usage of analgesics (OR: 3.17, 95% CI: 2.07-4.86, p-value: <0.001); and mild to extreme heavy bleeding (OR: 1.64, 95% CI: 1.01-2.67, p-value: 0.05) and pimples/acne (OR: 1.57, 95% CI: 0.98-2.54, p-value: 0.06). Ampicillin, tetracycline, ciprofloxacin and metronidazole were used to treat the most symptoms. Doctors or nurses (6%, 95% CI: 4-7%), friends (6%, 95% CI: 4-7%) and family members (7%, 95% CI: 5-8%) were most likely to recommend the use of antibiotics for menstrual symptoms, while these drugs were most often obtained from local chemists or pharmacists (10.2%, 95% CI: 8-12%). Conclusions: This is the first formal study to report that approximately 1 out of 4 university women surveyed in Southwest Nigeria self-medicate with antibiotics to treat menstrual symptoms. This practice could provide monthly, low-dose exposures to antibiotics among users. Further studies are necessary to evaluate the impacts of selfmedication on student health.

Environmental Impacts on Fecal Indicator Bacteria in 5 National Park Recreational Water Areas

2012-07-11T02:31:22Z

Title: Environmental Impacts on Fecal Indicator Bacteria in 5 National Park Recreational Water Areas Authors: Raspanti, Greg A. Abstract: The National Park Service oversees 397 park units throughout the 50 states and US territories. Due to the high visitation, protecting the health of visitors is a top priority. Fecal contamination in recreational water can occur as a result of land use practices and weather related factors. The aim of this study is to investigate weather related factors and land use factors that contribute to fecal contamination in five National Park units. Overall, rainfall proved to be highly predictive of subsequent elevations in fecal bacteria. Specifically, same day rainfall and day prior to the sampling day rainfall showed the strongest association with elevated fecal bacteria levels. Seasonal variation of fecal bacteria was generally higher in the summer months. The land use variables were not highly predictive of fecal bacteria levels. The results of this study can be used by park managers to better predict variations in fecal contamination.