Bacteriophage Isolated From The Environment And E. Coli Of Meat Origin As A Reservoir Of Antibiotic Resistance

ABSTRACT BACTERIOPHAGE ISOLATED FROM THE ENVIRONMENT AND E. COLI OF MEAT ORIGIN AS A RESERVOIR OF ANTIBIOTIC RESISTANCE by MANISHA POLUR April 2014 Advisor: Dr. Yifan Zhang Major: Nutrition and Food Science Degree: Master of Science This study was aimed to determine the extent of antibiotic resistance reservoir in bacteriophage. Bacteriophages were isolated and purified from waste water treatment plants, Detroit river, Belle Isle, Urban Garden soils and examined for the presence of beta-lactam antibiotic resistance genes. Thirty E. coli isolates from retail meat were analyzed for the presence of beta-lactam antibiotic resistance genes. 95% of E. coli them carried at least one antibiotic resistance gene on their genome. Bacteriophages were induced from the E. coli isolates by subjecting them to mitomycin C, thereby creating a stressful environment resulting in the release of prophages. Phages were induced from 40% of E. coli and isolated from 70% of the environmental samples by spot lysis assay by using two E. coli indicator strains. Phage DNA was analyzed for several beta-lactamase genes such as blaTEM-1, blaCMY-2, blaCTX-M1, blaOXA-2 and blaSHV-1. Among the bacteriophages induced from the E. coli isolates, all of them carried the blaTEM-1 genes on their DNA and 20% of them carried the blaCMY-2 genes. Forty percent of phages isolated from environmental samples carried blaTEM-1 and 60% of them carried blaCMY-2. This study suggests that phage from the environment and bacteria can be an important reservoir of antibiotic resistance

Overexpression of HTRA1 Leads to Ultrastructural Changes in the Elastic Layer of Bruch's Membrane via Cleavage of Extracellular Matrix Components

Variants in the chromosomal region 10q26 are strongly associated with an increased risk for age-related macular degeneration (AMD). Two potential AMD genes are located in this region: ARMS2 and HTRA1 (high-temperature requirement A1). Previous studies have suggested that polymorphisms in the promotor region of HTRA1 result in overexpression of HTRA1 protein. This study investigated the role of HTRA1 overexpression in the pathogenesis of AMD. Transgenic Htra1 mice overexpressing the murine protein in the retinal pigment epithelium (RPE) layer of the retina were generated and characterized by transmission electron microscopy, immunofluorescence staining and Western Blot analysis. The elastic layer of Bruch's membrane (BM) in the Htra1 transgenic mice was fragmented and less continuous than in wild type (WT) controls. Recombinant HTRA1 lacking the N-terminal domain cleaved various extracellular matrix (ECM) proteins. Subsequent Western Blot analysis revealed an overexpression of fibronectin fragments and a reduction of fibulin 5 and tropoelastin in the RPE/choroid layer in transgenic mice compared to WT. Fibulin 5 is essential for elastogenesis by promoting elastic fiber assembly and maturation. Taken together, our data implicate that HTRA1 overexpression leads to an altered elastogenesis in BM through fibulin 5 cleavage. It highlights the importance of ECM related proteins in the development of AMD and links HTRA1 to other AMD risk genes such as fibulin 5, fibulin 6, ARMS2 and TIMP3

Increased BMI is Associated with School Absenteeism Among US School Aged Children and Adolescents

Objective: Severe school absence may be one underlying cause of poor school performance among overweight and obese children. We examined the associations between school absenteeism and body mass index (BMI) in a nationally representative sample of children. Methods and Procedures: We analyzed the data of 1,387 children (6-11 y) and 2,185 adolescents (12-19 y), who completed an interview and anthropometric measurement as a part of the National Health and Nutrition Examination Survey, 2005-2008. CDC 2000 growth chart was used to categorize BMI status, and school days missed during the past 12 months was assessed by asking the proxies or interviewees. Results: The prevalence of obese and overweight were 18.96 (SE=1.44), and 16.41(0.78)% respectively among study populations. The means of school days missed in the last 12 months were not statistically different between normal weight, overweight and obese groups, 3.79 (SE=0.56), 3.86 (0.38) and 4.31 (0.01) days respectively. However, when more than 2 days missed per school month was defined as severe absenteeism, the prevalence of severe absenteeism were 1.57%, 2.99% and 4.94% respectively among 6- 11 years old children with normal, overweight and obese. The adjusted odds of being severe absentee were 2.18 (95% CI = 0.61-7.73) and 3.79 (1.45-9.91) respectively among overweight and obese children compared to normal weight peers (p for trend test \u3c 0.01). No significant association was found among adolescents. Conclusion: Increased body weight is independently associated with severe absenteeism

Role of HTRA1, a serine protease, in the progression of articular cartilage degeneration

This study is to investigate the possible role of high temperature requirement A 1 (HtrA1) in the articular cartilage degeneration. Paraffin sections were prepared from the knee and temporomandibular (TM) joints of four mouse OA models; two of the models had a genetic mutation (type IX collagen-deficient and type XI collagen-haploinsufficient) and two were surgically induced (destabilization of the medial meniscus of knee joint and discectomy of TM joint). The HtrA1 protein expression profiles of the prepared sections were examined by immunohistostaining. The level of HtrA1 mRNA in the articular cartilage taken from the knee joints of one of the genetically mutated OA models was determined by real-time PCR. Double immunohistostaining was used to examine the expression of co-localization of HtrA1 with type VI collagen and HtrA1 with discoidin domain receptor 2 (Ddr2) in the articular cartilage of knee joints from the genetically mutated OA model. The expression of HtrA1 was found to be increased in the knee and TM joints of these four models at early stages of the disease. An examination of the knee joint of a mutant mouse indicated an 8-fold increase in the level of HtrA1 mRNA, when compared to the levels observed in the knee joints of its wild-type littermates. Pericellular type VI collagen was not present in chondrocytes expressing HtrA1. Meanwhile, the expression of HtrA1 was associated with the expression of Ddr2 in the chondrocytes. Results indicate that HtrA1 may disrupt the pericellular matrix network, resulting in alteration of chondrocyte metabolisms. This eventually leads to O

Study Guides: To Give or Not to Give? That is the Question!

Presented at SoTL Commons Conference Study guides are a form of test preparation for students, which instructors may or may not use. Although seemingly innocuous, students sometimes demand them, while some instructors refuse to provide them. What underlying perceptions led to this dichotomy? This SoTL research project looks at how both students and instructors understand the role of test study guides. This session will present and evaluate data from surveys taken by college students and professors on their perception of test study guides, and will also invite the audience to make their own observations and to draw conclusions from the information. It will address when study guides are appropriate, how study guides are useful to student learning, and how they are helpful to instructors in achieving learning outcomes. Overall, the session aims to make sense of the use (or non-use) of study guides for student learning