Prevalent drug resistance among oral yeasts from asymptomatic patients in Hainan, China.

The oral cavity is a significant niche of the human microbiome and a gateway for the microbiota in many other human body sites. As a result, understanding the oral microbiota has broad implications for the prevention and management of human infectious diseases. Opportunistic yeast infections are among the most prevalent fungal infections of humans, and most opportunistic yeast pathogens are common residents of the oral mucosa.

[Immunological analysis of piperaquine-resistant murine model of Plasmodium berghei ANKA strain].

Objective: To analyze the immunological characteristics of murine model of piperaquine sensitive (PQS) line and resistant (PQR) line of Plasmodium berghei (Pb) ANKA strain.

Methods: 64 Kunming mice were divided into three groups, 16 in each of groups A and C, 32 in group B (16 of 32 were used for observing survival days). Each mouse in groups A and B was infected with 1 x 10(7) erythrocytic stage parasites of PbPQS and PbPQR, respectively.

Metabolic activation of polycyclic and heterocyclic aromatic hydrocarbons and DNA damage: a review.

Polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic compounds (HACs) constitute a major class of chemical carcinogens present in the environment. These compounds require activation to electrophilic metabolites to exert their mutagenic or carcinogenic effects. There are three principal pathways currently proposed for metabolic activation of PAH and HAC: the pathway via bay region dihydrodiol epoxide by cytochrome P450 enzymes (CYPs), the pathway via radical cation by one-electron oxidation, and the ortho-quinone pathway by dihydrodiol dehydrogenase (DD).

A metabolic activation mechanism of 7H-dibenzo[c,g]carbazole via o-quinone. Part 2: covalent adducts of 7H-dibenzo[c,g]carbazole-3,4-dione with nucleic acid bases and nucleosides.

7H-dibenzo[c,g]carbazole (DBC) is a potent multispecies, multisite carcinogen present in the environment. The metabolic activation pathways of DBC are not completely known. It is hypothesized that DBC may be metabolically activated by oxidation to the reactive Michael acceptor o-quinones, which can form stable and depurinating DNA adducts.