Comparative compositional analysis of cassava brown streak disease resistant 4046 cassava and its non-transgenic parental cultivar.

Compositional analysis is an important component of an integrated comparative approach to assessing the food and feed safety of new crops developed using biotechnology. As part of the safety assessment of cassava brown streak disease resistant 4046 cassava, a comprehensive assessment of proximates, minerals, amino acids, fatty acids, vitamins, anti-nutrients, and secondary metabolites was performed on leaf and storage root samples of 4046 cassava and its non-transgenic parental control, TME 204, collected from confined field trials in Kenya and Uganda over two successive cropping cycles. Among the 100 compositional components that were assessed in samples of 4046 and control TME 204 cassava roots (47 components) and leaves (53 components), there were no nutritionally relevant differences noted. Although there were statistically significant differences between the transgenic and control samples for some parameters, in most cases the magnitudes of these differences were small ( < 20%), and in every case where comparative literature data were available, the mean values for 4046 and control cassava samples were within the range of normal variation reported for the compositional component in question. Overall, no consistent patterns emerged to suggest that biologically meaningful adverse changes in the composition or nutritive value of the leaves or storage roots occurred as an unintended or unexpected consequence of the genetic modification resulting in 4046 cassava. The data presented here provide convincing evidence of the safety of 4046 cassava with respect to its biochemical composition for food and feed, and it could be considered as safe as its non-transgenic control.

Use of transgenic oryzacystatin-I-expressing plants enhances recombinant protein production.

Plants are an effective and inexpensive host for the production of commercially interesting heterologous recombinant proteins. The Escherichia coli-derived glutathione reductase was transiently expressed as a recombinant model protein in the cytosol of tobacco plants using the technique of leaf agro-infiltration. Proteolytic cysteine protease activity progressively increased over time when glutathione reductase accumulated in leaves. Application of cysteine protease promoter-GUS fusions in transgenic tobacco identified a cysteine protease NtCP2 expressed in mature leaves and being stress responsive to be expressed as a consequence of agro-infiltration. Transgenic tobacco plants constitutively expressing the rice cysteine protease inhibitor oryzacystatin-I had significantly lower cysteine protease activity when compared to non-transgenic tobacco plants. Lower cysteine protease activity in transgenic plants was directly related to higher glutathione reductase activity and also higher glutathione reductase amounts in transgenic plants. Overall, our work has demonstrated as a novel aspect that transgenic tobacco plants constitutively expressing an exogenous cysteine protease inhibitor have the potential for producing more recombinant protein which is very likely due to the reduced activity of endogenous cysteine protease.

Bacterial Uropathogens in Urinary Tract Infection and Antibiotic Susceptibility Pattern in Jimma University Specialized Hospital;Southwest Ethiopia

"BACKGROUND: Urinary tract infection (UTI) is one of the most common bacterial infections encountered by clinicians in developing countries. Area-specific monitoring studies aimed to gain knowledge about the type of pathogens responsible for urinary tract infections and their resistance patterns may help the clinician to choose the correct empirical treatment. Therefore; the aim of this study was to determine the type and antibiotic resistance pattern of the urinary pathogens isolated from patients attending Jimma University Specialized Hospital from April to June 2010. METHODS: A hospital based cross sectional stud was conducted and urine samples were collected using the mid-stream ""clean catch"" method from 228 clinically-suspected cases of urinary tract infections and tested bacteriologically using standard procedures. Antimicrobial susceptibility test was performed for the isolated pathogens using Kirby-Bauer disk diffusion method according to Clinical and Laboratory Standards Institute guidelines. RESULTS: - Significant bacteria were detected from 9.2of the total patients. The most common pathogens isolated were Escherichia coli (33.3); Klebsiella pneumoniae (19) and S. saprophyticus (14.3). E. coli and Klebsiella pneumoniae showed the highest percentage of resistance to ampicillin and amoxacillin (100) however; all isolates of E. coli and K. pneumoniae were susceptible to ciprofloxacin. S. saprophyticus and S. aureus were resistant to ampicillin (100) and amoxicillin (66.7). For all UTI isolates; least resistance was observed against drugs such as ceftriaxone; gentamycin and chloramphenicol. CONCLUSION: - This study finding showed that E. coli isolates were the predominant pathogens and the presence of bacterial isolates with very high resistance to the commonly prescribed drugs that in turn leaves the clinicians with very few alternative options of drugs for the treatment of UTIs. As drug resistance among bacterial pathogens is an evolving process; routine surveillance and monitoring studies should be conducted to provide physicians knowledge on the updated and most effective empirical treatment of UTIs."

Epidemiologic Modeling of HIV/AIDS: Use of Computational Models to Study the Population Dynamics of the Disease to Assess Effective Intervention Strategies for Decision-making.

Computational models and simulations are becoming central research tools in epidemiology, biology, and other fields. Epidemiologic research involves the study of a complex set of host, environment and causative agent factors as these interact to impact health and diseases in any population. The most advanced of these efforts have focused on micro (cellular) or macro (human) population levels. The dynamic interplay of HIV with a focus in its hosts at the cellular level provides the micro-epidemiologic basis, while the dynamic interplay of multifactorial determinants: biomedical, behavioral, and socioeconomic factors provide the macro-epidemiologic basis at the human population level. We have developed the computational tools and mathematical approaches to study the population-level effects of various drugs on HIV to integrate models from micro to macro- levels in a seamless fashion. The critical variables that facilitate transmission of HIV and intracellular interactions and molecular kinetics were considered. Such multilevel models are essential if we are to develop quantitative, predictive models of complex biological systems such as HIV/AIDS.

A Conceptual Multivariate Modelling Approach for Integrating Epidemiologic and Psychosocial Determinants to Examine the Epidemiology of Diseases in Under-served Populations.

Epidemiologic research involves the study of a complex set of host, environment and causative agent factors as these interact to impact health and diseases in any population. A conceptual multivariate modelling approach for integrating epidemiologic and psychosocial determinants to examine the epidemiology of chronic and infectious diseases in under-served populations in the USA was developed. Our approach relies upon systems analysis, i.e. integrating concepts and methods in epidemiology with mathematics and statistics along with computational methods and tools to rigorously examine the dynamics of diseases such as the Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) in a community. We used a multifactorial and quantitative epidemiologic (static) model that interrelates multiple determinants including biomedical, behavioral, and socioeconomic factors to analyze morbidity and mortality due to HIV/AIDS. The research involved participation of the community in the collection of socioeconomic, demographic, environmental, epidemiologic and biomedical data. In collaboration with Montgomery AIDS Outreach (MAO), a community based Organization in Montgomery, Alabama; blood samples were collected and tested using Orasure HIV testing kits to establish infection status with HIV/AIDS. Using these models, evaluations of various intervention scenarios with the objective of recommending effective strategies to minimize the risk of new HIV infections and/or manage existing diseases in a community can be generated.

Typhoid Fever in Ethiopia

This review focuses on the reports of salmonellosis by investigators in different parts of Ethiopia; in particular focusing on the levels of typhoid fever. Many of the reports are published in local journals that are not available online. There have been seven studies which diagnosed typhoid fever by laboratory culture and there is no coordinated epidemiological surveillance. All conducted research and reports from different health institutions in Ethiopia indicate that typhoid fever was still a common problem up to the most recent study in 2000 and that the extensive use of first-line drugs has led to the development of multiple drug resistance. In the sites covered by this review; the total number of published cases of typhoid fever dropped over time reflecting the decline in research capacity in the country. Data on the proportion of patients infected by different serovars of Salmonella suggest that the non-Typhi serovars of Salmonella are increasing. The published evidence suggests that typhoid fever is a current public health problem in Ethiopia although population based surveys; based on good microbiological diagnosis; are urgently needed. Only then can the true burden of enteric fever be estimated and the benefit of public health control measures; such as health education; safe water provision; improved food hygienic practices and eventually vaccination; be properly assessed