8-OxoG-Dependent Regulation of Global Protein Responses Leads to Mutagenesis and Stress Survival in .

The guanine oxidized (GO) system of , composed of the YtkD (MutT), MutM and MutY proteins, counteracts the cytotoxic and genotoxic effects of the oxidized nucleobase 8-OxoG. Here, we report that in growing cells, the genetic inactivation of GO system potentiated mutagenesis (HPM), and subsequent hyperresistance, contributes to the damaging effects of hydrogen peroxide (HO) (HPHR). The mechanism(s) that connect the accumulation of the mutagenic lesion 8-OxoG with the ability of to evolve and survive the noxious effects of oxidative stress were dissected.

Progesterone analogs influence germination of Clostridium sordellii and Clostridium difficile spores in vitro.

Clostridium sordellii and Clostridium difficile are closely related anaerobic Gram-positive, spore-forming human pathogens. C. sordellii and C.

The α₂β₁ integrin is a metastasis suppressor in mouse models and human cancer.

Integrins regulate cell-cell and cell-matrix adhesion and thereby play critical roles in tumor progression and metastasis. Although work in preclinical models suggests that β1 integrins may stimulate metastasis of a number of cancers, expression of the β1 subunit alone has not been shown to be a useful prognostic indicator in human cancer patients. Here we have demonstrated that the α2β1 integrin suppresses metastasis in a clinically relevant spontaneous mouse model of breast cancer.

Mapping interactions between germinants and Clostridium difficile spores.

Germination of Clostridium difficile spores is the first required step in establishing C. difficile-associated disease (CDAD). Taurocholate (a bile salt) and glycine (an amino acid) have been shown to be important germinants of C.

Kinetic evidence for the presence of putative germination receptors in Clostridium difficile spores.

Clostridium difficile is a spore-forming bacterium that causes Clostridium difficile-associated disease (CDAD). Intestinal microflora keeps C. difficile in the spore state and prevents colonization.

Requirements for germination of Clostridium sordellii spores in vitro.

Clostridium sordellii is a spore-forming, obligately anaerobic, Gram-positive bacterium that can cause toxic shock syndrome after gynecological procedures. Although the incidence of C. sordellii infection is low, it is fatal in most cases.

Effect of tillage and rainfall on transport of manure-applied Cryptosporidium parvum oocysts through soil.

Most waterborne outbreaks of cryptosporidiosis have been attributed to agricultural sources due to the high prevalence of Cryptosporidium oocysts in animal wastes and manure spreading on farmlands. No-till, an effective conservation practice, often results in soil having higher water infiltration and percolation rates than conventional tillage. We treated six undisturbed no-till and six tilled soil blocks (30 by 30 by 30 cm) with 1 L liquid dairy manure containing 10(5) C.

alpha2beta1 integrin expression in the tumor microenvironment enhances tumor angiogenesis in a tumor cell-specific manner.

To define the role of the alpha2beta1 integrin in pathologic angiogenesis, we investigated tumor-associated growth and angiogenesis in wild-type and alpha2-null mice. Our findings reveal that the alpha2beta1 integrin plays an important role in angiogenesis via regulation of VEGFR1 expression. When challenged with B16F10 melanoma cells, mice lacking alpha2beta1 integrin ex-pression exhibit increased tumor angiogenesis associated with up-regulated VEGFR1 expression.

Development of a sensitive detection system for Cryptosporidium in environmental samples.

The identification of Cryptosporidium species and genotypes is necessary to determine sources of infection in outbreaks and the risk factors associated with their transmission. Few studies have applied isolation methods to field samples because of difficulties with detection of oocysts in environmental samples, particularly in soil and manure. The objective of this study was to develop an easy to use method which can be applied to field samples to rapidly detect the presence of Cryptosporidium parasites and identify their species.

A review of the biology and epidemiology of cryptosporidiosis in humans and animals.

The epidemiology of cryptosporidiosis, an infection caused by several genotypically and phenotypically diverse Cryptosporidium species, has been dynamically changing over the past decade from that of a rare, largely asymptomatic infection to an acute enteric disease of animals and humans. In this review, the current understanding of factors (biology and epidemiology) contributing to the emergence of cryptosporidiosis in animals, including parasite biology, genetic diversity, environmental spread, livestock production trends, presence of the parasite in livestock and companion animals, and potential risk of transmission from animals to humans is highlighted. Potential control measures and the role of veterinary and medical professionals in the prevention of cryptosporidiosis are also discussed.

Pathogenesis of human and bovine Cryptosporidium parvum in gnotobiotic pigs.

To compare the pathogenesis of human genotype 1 (HuG1) and bovine genotype 2 (BoG2) Cryptosporidium parvum, neonatal gnotobiotic pigs were given 1-10 HuG1 or BoG2 oocysts. The prepatent and patent periods were significantly longer for HuG1 than for BoG2 C. parvum (prepatent, 8.