Contributions of tropodithietic acid and biofilm formation to the probiotic activity of Phaeobacter inhibens.

Background: The probiotic bacterium Phaeobacter inhibens strain S4Sm, isolated from the inner shell surface of a healthy oyster, secretes the antibiotic tropodithietic acid (TDA), is an excellent biofilm former, and increases oyster larvae survival when challenged with bacterial pathogens. In this study, we investigated the specific roles of TDA secretion and biofilm formation in the probiotic activity of S4Sm.

Results: Mutations in clpX (ATP-dependent ATPase) and exoP (an exopolysaccharide biosynthesis gene) were created by insertional mutagenesis using homologous recombination.

Mitochondrial uncoupling links lipid catabolism to Akt inhibition and resistance to tumorigenesis.

To support growth, tumour cells reprogramme their metabolism to simultaneously upregulate macromolecular biosynthesis while maintaining energy production. Uncoupling proteins (UCPs) oppose this phenotype by inducing futile mitochondrial respiration that is uncoupled from ATP synthesis, resulting in nutrient wasting. Here using a UCP3 transgene targeted to the basal epidermis, we show that forced mitochondrial uncoupling inhibits skin carcinogenesis by blocking Akt activation.

The heat is on: Molecular mechanisms of drug-induced hyperthermia.

Thermoregulation is an essential homeostatic process in which critical mechanisms of heat production and dissipation are controlled centrally in large part by the hypothalamus and peripherally by activation of the sympathetic nervous system. Drugs that disrupt the components of this highly orchestrated multi-organ process can lead to life-threatening hyperthermia. In most cases, hyperthermic agents raise body temperature by increasing the central and peripheral release of thermoregulatory neurotransmitters that ultimately lead to heat production in thermogenic effector organs skeletal muscle (SKM) and brown adipose tissue (BAT).

Seasonality, timing, and climate drivers of influenza activity worldwide.

Background: Although influenza is a vaccine-preventable disease that annually causes substantial disease burden, data on virus activity in tropical countries are limited. We analyzed publicly available influenza data to better understand the global circulation of influenza viruses.

Method: We reviewed open-source, laboratory-confirmed influenza surveillance data.

Hyponatremia, hypochloremia, and hypoalbuminemia predict an increased risk of mortality during the first year of antiretroviral therapy among HIV-infected Zambian and Kenyan women.

Early mortality rates after initiating antiretroviral therapy (ART) are high in sub-Saharan Africa. We examined whether serum chemistries at ART initiation predicted mortality among HIV-infected women. From May 2005 to January 2007, we enrolled women initiating ART in a prospective cohort study in Zambia and Kenya.

Increased rates of bone fracture among HIV-infected persons in the HIV Outpatient Study (HOPS) compared with the US general population, 2000-2006.

Background: Among persons with HIV infection, low bone mineral density is common and has raised concerns about increased risk of fracture.

Methods: We analyzed data from the HIV Outpatient Study (HOPS), an open prospective cohort study of HIV-infected adults who were followed up at 10 US HIV clinics. We assessed rates of first fractures at any anatomic site during the period 2000-2008.

Low vitamin D among HIV-infected adults: prevalence of and risk factors for low vitamin D Levels in a cohort of HIV-infected adults and comparison to prevalence among adults in the US general population.

Background: we explored serum 25-hydroxyvitamin D (25[OH]D) levels and associated factors for insufficiency or deficiency in an adult human immunodeficiency virus (HIV) cohort and compared 25(OH)D levels with those in the general US population.

Methods: using baseline data from the Study to Understand the Natural History of HIV and AIDS in the Era of Effective Therapy (SUN), a prospective, observational cohort study of HIV-infected adults enrolled at 7 HIV specialty clinics in 4 US cities from March 2004 to June 2006, we estimated the prevalence of vitamin D insufficiency or deficiency (defined as 25(OH)D levels <30 ng/mL), standardized by age, race, and sex. Using multiple logistic regression, we examined risk factors for vitamin D insufficiency or deficiency.

Adult hospitalizations for laboratory-positive influenza during the 2005-2006 through 2007-2008 seasons in the United States.

Background: Rates of influenza-associated hospitalizations in the United States have been estimated using modeling techniques with data from pneumonia and influenza hospitalization discharge diagnoses, but they have not been directly estimated from laboratory-positive cases.

Methods: We calculated overall, age-specific, and site-specific rates of laboratory-positive, influenza-associated hospitalization among adults and compared demographic and clinical characteristics and outcomes of hospitalized cases by season with use of data collected by the Emerging Infections Program Network during the 2005-2006 through 2007-2008 influenza seasons.

Results: Overall rates of adult influenza-associated hospitalization per 100,000 persons were 9.