Analysis of the Candida albicans Phosphoproteome.

Candida albicans is an important human fungal pathogen in both immunocompetent and immunocompromised individuals. C. albicans regulation has been studied in many contexts, including morphological transitions, mating competence, biofilm formation, stress resistance, and cell wall synthesis. Analysis of kinase- and phosphatase-deficient mutants has made it clear that protein phosphorylation plays an important role in the regulation of these pathways. In this study, to further our understanding of phosphorylation in C. albicans regulation, we performed a deep analysis of the phosphoproteome in C. albicans. We identified 19,590 unique peptides that corresponded to 15,906 unique phosphosites on 2,896 proteins. The ratios of serine, threonine, and tyrosine phosphosites were 80.01%, 18.11%, and 1.81%, respectively. The majority of proteins (2,111) contained at least two detected phosphorylation sites. Consistent with findings in other fungi, cytoskeletal proteins were among the most highly phosphorylated proteins, and there were differences in Gene Ontology (GO) terms for proteins with serine and threonine versus tyrosine phosphorylation sites. This large-scale analysis identified phosphosites in protein components of Mediator, an important transcriptional coregulatory protein complex. A targeted analysis of the phosphosites in Mediator complex proteins confirmed the large-scale studies, and further in vitro assays identified a subset of these phosphorylations that were catalyzed by Cdk8 (Ssn3), a kinase within the Mediator complex. These data represent the deepest single analysis of a fungal phosphoproteome and lay the groundwork for future analyses of the C. albicans phosphoproteome and specific phosphoproteins.

Nonalcoholic fatty liver disease is associated with insulin resistance in a young Hispanic population.

OBJECTIVE: To investigate whether nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR) in a young Hispanic population. METHODS: A cross-sectional study was performed in Bogotá, Colombia, during 2006 in 263 males from the Colombian Air Force (age range 29-54 years). Anthropometric measurements and biochemical determinations (glycemia, lipid profile, insulin, and HOMA-IR) were obtained in order to determine the presence of metabolic syndrome (MS) criteria and insulin resistance in this population. In addition, ultrasound studies were performed to evaluate the presence of NAFLD. RESULTS: NAFLD was detected in 26.6% (n=70) of the subjects. Thirty four individuals had complete MS criteria (48.5%). The presence of NAFLD was associated with higher insulin levels (11.0±5.1 vs. 6.6±3.6, p=0.001), and its prevalence increased from 11% (n=8), to 24% (n=17) to 64% (n=45) from the lowest to the highest HOMA-IR tertile. Body mass index, triglycerides and subcutaneous and visceral fat were found to be independent predictors of NAFLD. CONCLUSIONS: These results suggest that NAFLD is associated with insulin resistance and extrahepatic adiposity in nondiabetic young Hispanic population.

Transmission Efficiency of Potato virus Y strains PVYO and PVYN-Wi by Five Aphid Species.

Potato virus Y (PVY) is a reemerging problem in potato production in North America. Although the "ordinary" strain, PVYO, is still the dominant isolate in U.S. seed potatoes, the recombinant strain of the virus PVYN-Wi (= PVYN:O) has become widespread. An increase in the prevalence of a PVY strain could be due to differences in the efficiency of transmission by aphid vectors. The transmission efficiency by a clone of Myzus persicae was determined for five isolates each of PVYO and PVYN-Wi. An aphid transmission assay was developed based on the use of potato seedlings from true potato seed, allowing for greater control of plant age and growth stage. No apparent differences in transmission by M. persicae were observed. Single isolates of PVYO and PVYN-Wi were tested for their ability to be transmitted from potato to potato by five aphid species: Aphis glycines, A. gossypii, A. nasturtii, M. persicae, and Rhopalosiphum padi. Both PVY isolates showed a similar transmission phenotype in being transmitted efficiently by M. persicae but very poorly or not at all by A. glycines, A. gossypii, and R. padi. The aphid A. nasturtii transmitted both isolates with an intermediate level of efficiency. The data do not support a model for a differential aphid transmissibility being responsible for the increase in the prevalence of PVYN-Wi.

Epidemiology of tuberculosis in the Americas: the Stop TB strategy and the millennium development goals.

BACKGROUND: Tuberculosis (TB), a preventable and curable disease, remains a major public health threat in the poorest regions of the Americas. The DOTS strategy was implemented to control TB in the region in 1993, and the new Stop TB strategy, emphasizing high-quality DOTS expansion, in 2006. OBJECTIVES: To describe TB epidemiology in the region of the Americas from 1994 to 2005 and to analyze the progress made towards and prospects for achieving Goal 6 of the Millennium Development Goals (MDGs) by 2015. METHODS: TB incidence, mortality and prevalence rates as well as DOTS coverage and DOTS treatment success rates were collated from the World Health Organization (WHO) databases from 1994 to 2005. RESULTS: DOTS coverage and DOTS treatment success rates rose steadily from 1994 to 2005, with 88% of the population covered under DOTS by 2005, and an 80% success rate by the end of 2004. The TB incidence, prevalence and mortality rates have also decreased steadily from 1994 to date, but differ with respect to the various scenarios. CONCLUSIONS: With the exception of some countries, further reduction in TB incidence, prevalence and deaths by 2015 is possible. Widespread implementation of DOTS should continue in order to meet WHO targets and attain the MDGs.