Urinary metabolites of polycyclic aromatic hydrocarbons in relation to idiopathic male infertility.

Background: Limited studies have suggested that male reproductive function might be associated with exposure to polycyclic aromatic hydrocarbons (PAHs).

Methods: Five hundred and thirteen idiopathic infertile male subjects and 273 fertile males as controls were recruited in this study, through eligibility screening procedures. Individual exposures to PAHs were measured as spot urinary concentrations of four PAH metabolites, including 1-hydroxynaphthalene (1-N), 2-hydroxynaphthalene (2-N), 1-hydroxypyrene (1-OHP) and 2-hydroxyfluorene (2-OHF), which were adjusted by urinary creatinine (CR).

Serotype distribution and antimicrobial resistance patterns of Streptococcus pneumoniae isolated from children in China younger than 5 years.

This study examined the epidemiology, antibiotic susceptibility, and serotype distribution of Streptococcus pneumoniae associated with invasive and noninvasive pneumococcal disease in children in China. A total of 451 clinical isolates from children (age, <5 years) were collected from 8 cities from January 2005 to December 2006, including 31 isolated from invasive disease. In vitro susceptibility to 14 antimicrobial agents was determined by the agar dilution method.

Metabolism of terephthalic acid and its effects on CYP4B1 induction.

Objective: To investgate the metabolism of terephthalic acid (TPA) in rats and its mechanism. Methods Metabolism was evaluated by incubating sodium terephthalate (NaTPA) with rat normal liver microsomes, or with microsomes pretreated by phenobarbital sodium, or with 3-methycholanthrene, or with diet control following a NADPH-generating system. The determination was performed by high performance liquid chromatography (HPLC), and the mutagenic activation was analyzed by umu tester strain Salmonella typhimurium NM2009.

Induction of bladder lesion by terephthalic acid and its mechanism.

Objective: To provide more information for rational evaluation of potential risks of terephthalic acid (TPA), we studied the effects of TPA on rats' bladders in 90 days after TPA exposure.

Methods: Sprague Dawley rats were subdivided into five groups, ingesting 0%, 0.04%, 0.

Effect of oral administration of terephthalic acid on testicular functions of rats.

To investigate the toxic effect of terephthalic acid (TPA) on testicular functions of rats, male Sprague-Dawley rats were orally administered TPA in diet at the levels 0 (control), 0.2, 1 and 5% for 90 days. Testicular functions were assessed by histopathology, testicular sperm head counts, daily sperm production, sperm motility (measured by computer-assisted sperm analysis, CASA), biochemical indices (marker testicular enzymes), and serum testosterone.