Gene Polymorphisms Among Geographical Isolates and the Potential as New Biomarkers for Gametocyte Detection.

The unique biological features of not only make it difficult to control but also to eliminate. For the transmission of the malaria parasite from infected human to the vector, gametocytes play a major role. The transmission potential of a malarial infection is inferred based on microscopic detection of gametocytes and molecular screening of genes in the female gametocytes.

Chlorosilane acute inhalation toxicity and development of an LC50 prediction model.

The acute inhalation toxicity of 10 chlorosilanes was investigated in Fischer 344 rats using a 1-h whole-body vapor inhalation exposure and a 14-day recovery period. The median lethal concentration (LC50(1)) for each material was calculated from the nominal exposure concentrations and mortality. Experimentally derived LC50(1) values for monochlorosilanes (4257-4478 ppm) were greater than those for dichlorosilanes (1785-2092 ppm), which were greater than those for trichlorosilanes (1257-1611 ppm).

Inhalation toxicology of octamethylcyclotetrasiloxane (D4) following a 3-month nose-only exposure in Fischer 344 rats.

Octamethylcyclotetrasiloxane (D4) is a low-molecular-weight cyclic siloxane used primarily in the synthesis of silicone polymers. The objective of the present study was to evaluate the subchronic toxicity of D4 following a 3-month nose-only inhalation exposure. Male and female Fischer 344 rats (20/sex/group) were exposed 6 h/day, 5 days/week for 3 months to vapor concentrations of 0, 35, 122, 488, and 898 ppm D4.

Hexamethyidisiloxane: A 13-week subchronic whole-body vapor inhalation toxicity study in Fischer 344 rats.

Hexamethyldisiloxane (HMDS) is a volatile linear siloxane dimer used in many applications, including precision cleaning, active ingredient carrier, and as a manufacturing intermediate. The purpose of this study was to characterize the subchronic vapor inhalation toxicity of the material as part of a comprehensive toxicology program. Groups of 20 male and 20 female Fischer 344 (F344) rats were exposed to nominal (and mean actual) vapor concentrations of 0, 50 (50), 200 (194), 600 (593), 1,500 (1,509) and 5,000 (5,012) ppm of HMDS, 6 hours per day, 5 days per week, for 13 weeks.

Repeated inhalation exposure to octamethylcyclotetrasiloxane produces hepatomegaly, transient hepatic hyperplasia, and sustained hypertrophy in female Fischer 344 rats in a manner similar to phenobarbital.

Octamethylcyclotetrasiloxane (D4) has been described as a phenobarbital-like inducer of hepatic enzymes. Phenobarbital (PB) and phenobarbital-like chemicals induce transient hepatic and thyroid hyperplasia and sustained hypertrophy in rats and mice. The extent to which these processes are involved with D4-induced hepatomegaly is not known.

Toxicology and humoral immunity assessment of octamethylcyclotetrasiloxane (D4) following a 28-day whole body vapor inhalation exposure in Fischer 344 rats.

Octamethylcyclotetrasiloxane, D4, is a low viscosity, silicone fluid consisting of four dimethyl-siloxy units ((CH3)2SiO)4 in a cyclic structure. It is primarily used as a building block in the industrial synthesis of long chain silicone polymers. The combination of D4 with decamethylcyclopentasiloxane (D5) is commonly referred to as cyclomethicone which has a wide range of applications as a formulation aid in personal care products.

Evaluation of octamethylcyclotetrasiloxane (D4) as an inducer of rat hepatic microsomal cytochrome P450, UDP-glucuronosyltransferase, and epoxide hydrolase: a 28-day inhalation study.

Repeated inhalation exposure to octamethylcyclotetrasiloxane (D4) produces a reversible and dose-related hepatomegaly and proliferation of hepatic endoplasmic reticulum in rats. However, the effects of D4 on the expression of cytochrome P450 enzymes have not been evaluated. In the present study, the time course for changes in hepatic microsomal cytochrome P450 enzyme expression following repeated inhalation exposure to D4 vapors was determined in male and female Fischer 344 rats.

Subchronic inhalation toxicity of 1,1,1,3-tetrachloropropane in rats.

The purpose of this study was to evaluate the inhalation toxicity of 1,1,1,3-tetrachloropropane (TCP), an intermediate in the production of chlorinated silicone fluids. Male and female Sprague-Dawley rats were exposed 6 hr/day, 5 days/week, for 90 days to TCP at concentrations of 0, 25, 75, or 225 ppm (Phase I study) and to 0, 1, 5, or 10 ppm (Phase II study). Phase II of the study was conducted because a no-observed-effect level was not achieved in Phase I.

Subchronic inhalation toxicity of tetramethoxysilane in rats.

Sprague-Dawley rats were exposed 6 hr/day, 5 days a week, for 28 days to tetramethoxysilane (TMOS) at concentrations of 0, 1, 5, and 10 ppm (Phase I study) and to 0, 15, 30, and 45 ppm (Phase II study). All of the rats exposed to 45 ppm TMOS died or were sacrificed in a moribund state during the 28-day study period. Statistically significant changes were observed in food consumption, body weights, and clinical chemistry parameters in the animals exposed to 30 ppm TMOS.

Development of optimal treatment tactics for alcohol withdrawal. I. Assessment and effectiveness of supportive care.

The relative roles of supportive care and pharmacotherapy in the treatment of alcohol withdrawal are not established. A reliable and validated withdrawal severity assessment scale (Clinical Institute Withdrawal Assessment for Alcohol, CIWA-A) was developed to assess initially and then follow the clinical course of 38 hospitalized chronic alcoholics requiring hospitalization for withdrawal but without serious concurrent medical or surgical problems. Supportive care, consisting of standardized half-hourly patient assessment (CIWA-A) and nursing care, was used as the initial treatment for all patients.

Carotid-vertebral artery blood transit time: results in healthy subjects and patients with schizophrenia and brain disease.

Estimation of blood transit time in the neck and the extension of this into the head was made by a method of electrical impedance, over a wide age range, in 159 healthy subjects, 160 schizophrenic patients, and 199 patients with organic brain disease. In each case, the distance between the electrocardiogram and the next succeeding pulse-volume impedance wave was measured and averaged over 30 serial wave forms. Chronological age proved a significant variable, transit times lengthening progressively with the age, but only for measurements extending into the head.