Community Health Workers as Agents of Health Promotion: Analyzing Thailand's Village Health Volunteer Program.

The village health volunteers (VHVs) have been a regular part of Thailand's health system since the 1960s. Despite widespread recognition, little research has been conducted to describe VHV activities, the settings in which VHVs provide help, how the program is administered, and how changing politics and health problems in Thailand have influenced the program. In order to understand the roles and practices of the VHVs, we conducted in-depth semi-structured interviews and focus groups with VHVs, community leaders and members, and public health officials in three semi-urban communities in central Thailand. Using the Social Ecological Framework, we mapped factors that influenced how the VHVs provided support, including governmental oversight, collaboration with public health officials, and community trust. These influences are discussed as "points of consideration," which help to identify the strengths and tensions within the VHV program and best practices in supporting and assessing community health worker efforts.

Variables that may enhance medical students' perceived preparedness for computer-based testing.

OBJECTIVE: To identify variables that may enhance medical student's preparedness for computer-based administration of the United States Medical Licensing Examination (USMLE). DESIGN: A cross-sectional survey of 301 medical students who completed a self-administered questionnaire. MEASUREMENTS: The questionnaire was designed to obtain information about students' computer resources, personal experience with computers, computer expertise, opinions about computers, experience with computer-based testing, perceived preparedness for the computer-based USMLE, and demographic variables. Variables related to students' perceived preparedness for the computer-based USMLE were identified by ordinal logistic regression. RESULTS: A significant regression model yielded four significant predictors: perceived preparedness for USMLE content (P: < 0.0001), opinions about computers (P: < 0.0012), gender (P: < 0.0001), and a gender by computer-based testing experience interaction (P: < 0. 0004). Computer resources, personal experience with computers, computer expertise, age, race, and year of medical school were not significant predictors. CONCLUSION: Students' perceived preparedness for computer-based administration of high-stakes examinations may be facilitated by preparing them for examination content, by enhancing their opinions about computers, and by increasing their computer-based testing experiences.

[Divorces, 1997]. / Ehescheidungen 1997.

PIP: Divorce statistics for 1997 are presented for Germany, for the former East and West Germany, and for each state. Retrospective data from 1960 to 1997 are included for comparative purposes. Information is given on duration of marriage, type of divorce, nationality, and number of children.^ieng

[40 years of the microcensus]. / 40 Jahre Mikrozensus.

PIP: This essay discusses the history, goals, scope, functions, methodology, and future of the German microcensus, which was begun in the Federal Republic of Germany in 1957. Particular attention is given to the issue of whether making participation voluntary would have a negative effect on data quality.^ieng

[Analyses of voluntary responses in the microcensus: are survey results distorted by voluntary responses?]. / Analysen zur Freiwilligkeit der Auskunftserteilung im Mikrozensus: sind Stichprobenergebnisse bei Freiwilliger Auskunftserteilung verzerrt?

PIP: An attempt is made to determine whether microcensus results in Germany are less reliable when responses to questions are voluntary rather than required. The analysis focuses on two questions that have been voluntary since 1991: highest level of general schooling completed and most recent occupational training completed. Data are from the 1991, 1992, and 1993 microcensuses. Earlier data are included for comparative purposes.^ieng

[On voluntary responding to microcensus questions]. / Zur Freiwilligkeit in der Auskunftserteilung im Mikrozensus.

PIP: The authors examine how the quality of German microcensus data has been affected by a 1990 law that made it voluntary rather than mandatory to respond to many questions. The analysis focuses on the year 1991 and on questions related to education and occupational training. Differences in the number of responses are analyzed according to region, age group, household size, community size, labor force participation, occupation, and whether the questions were asked orally or in writing.^ieng

Subchronic toxicity of all-trans-retinoic acid and retinylidene dimedone in Sprague-Dawley rats.

Sprague-Dawley rats received daily oral gavage doses of either 2-retinylidene-5,5-dimethyl-1,3-cyclohexanedione (retinylidene dimedone; 14, 50, 150, or 330 mg/kg) or all-trans-retinoic acid (1, 4, 14, or 50 mg/kg) for 13 weeks. Rats given 50 mg/kg of all-trans-retinoic acid developed numerous long-bone fractures and became moribund during the third week of the study. Those receiving lower dosages survived until scheduled termination, but the 14 mg/kg group showed clear signs of retinoid intoxication including growth depression, anemia, serum alkaline phosphatase elevation, bone fracture, and testicular degeneration. Exposure to retinylidene dimedone did not result in any treatment-related deaths, growth depression, or histopathologic lesions, even at the highest dose, 300 mg/kg. Animals given this dosage exhibited mild anemia, equivocal evidence of bone fracture, but no increase in alkaline phosphatase activity. Retinylidene dimedone appears to be considerably less toxic than all-trans-retinoic acid.

An orally administered microcapsule system for treating chronic renal failure patients.

Ingestible adsorbents for the removal of uremic metabolites are being investigated as adjunctive therapy in the treatment of chronic uremia. In particular, a microcapsule product containing urease and zirconium phosphate (UZP) has been investigated for removing urea. A dog model, simulating chronic uremia, was developed to investigate: (1) the concentration of various nitrogenous metabolites (urea, creatinine, and uric acid) in the GI tract, (2) flux rates of H2O and various nitrogenous metabolites in the GI tract, and (3) the efficacy of the microcapsule product. The results of these perfusion studies suggest that urea and creatinine can be removed from the GI tract via ingestible adsorbents. In addition, the model may be useful in investigating suspect uremic toxins, e.g., guanidinosuccinic acid (GSA). The reduction of blood urea nitrogen levels in the dog model when the animal was fed the microcapsule product was limited by the capacity of the zirconium phosphate to bind ammonium ion. Preliminary clinical studies with the microcapsule product indicate that it may be of potential adjunctive therapy in patients suffering from chronic renal failure.

The metabolism of ftorafur in the beagle dog and rhesus monkey.

1. Ftorafur, a fluorinated pyrimidine nucleoside antimetabolite, is metabolized by the beagle dog and rhesus monkey to 5-fluorouracil, which is subsequently biotransformed to the corresponding nucleosides, to alpha-fluoro-beta-ureidopropionic acid, to urea and to CO2. 2. In the dog, urea was the primary urinary metabolite while in the monkey, alpha-fluoro-beta-ureidopropionic acid predominated. 3. The dog and monkey excrete about 35 percent of the recovered dose as CO2. 4. The possibility that ftorafur is a relatively inactive transport form of 5-fluorouracil is discussed.

Comparison of the drug metabolizing enzymes in the liver and kidneys from homozygous nude swiss, heterozygous normal swiss, homozygous normal Swiss and DBA/2 mice.

The hepatic and renal microsomal drug metabolizing enzyme systems were isolated from homozygous nude Swiss (nu/nu), heterozygous normal Swiss (nu/+), homozygous normal Swiss (+/+) and DBA/2 mice. Microsomal protein and cytochrome P-450 concentrations were measured and the activity of ethylmorphine demethylase, aniline hydroxylase, aryl hydrocarbon hydroxylase and UDP-glucuronyl transferase were determined. Hepatic microsomes from both experimental groups carrying the nude gene were able to metabolize aniline and ethylmorphine more rapidly (20% and 36%, respectively) than the DBA/2 or Swiss homozygous normal mice. No difference between test groups was observed for hepatic aryl hydrocarbon hydroxylase or UDP-glucuronyl transferase activity. Kidney microsomes from mice carrying the nude gene had approximately twice the aryl hydrocarbon hydroxylase activity of the other two experimental groups. Renal mixed-function oxidase pathways measured for the homozygous nude mouse showed a higher overall rate of activity than the other three experimental groups. No significant difference in renal UDP-glucuronyl transferase was observed between mouse groups.

A comprehensive study of in vitro drug metabolism in several laboratory species.

A shortage of rhesus monkeys for use in drug toxicity studies has made it necessary to search for a potential replacement species in the event that one should be needed in the near future. To this end, 14 parameters of drug metabolism in hepatic microsomal and soluble fractions were examined in preparations from adult male and female rhesus monkeys, squirrel monkeys, Hanford miniature pigs, common tree shrews, and Sprague-Dawley rats. Model substrates were utilized and comparisons were made on a quantitative basis. All species tested demonstrated activity in all but one test assay and all showed some similarity to the rhesus. None of the species, however, was totally comparable to the rhesus in drug-metabolizing ability. The squirrel monkey showed the least similarity to the rhesus and the miniature pig was the most similar. With the exception of the expected differences in the rat, the tree shrew demonstrated the only sex difference in drug metabolism, the enzyme activities of females being higher than the male in several pathways. The data suggest that any of the four species tested could be a suitable replacement for the rhesus in studies of drug metabolism in vitro.

Characterization of the hepatic microsomal mixed-function oxidase enzyme system in miniature pigs.

Hepatic microsomal protein, cytochrome P-450, UDP-glucuronyltransferase, ethylmorphine demethylase, aniline hydroxylase, and aryl hydrocarbon hydroxylase levels were measured in the 2-, 4-, 5-, 6-, and 8-month-old Hanford miniature pig. The activities or concentrations of all of the liver parameters measured had apparently reached their adult plateau level by 2 months of age. The use of the miniature pig in toxicology research programs is discussed.

The use of high pressure liquid chromatography to study chemically induced alterations in the pattern of benzo[a]pyrene metabolism.

The metabolism of radiolabeled benzo[a]pyrene (BP) by control, 3-methyl-cholanthrene (3-MC) induced, and 1,1,1-trichloropropene-2,3-oxide (TCPO)-inhibited rat liver microsomes was measured using fluorescence, radiometric, and high-pressure liquid chromatographic (HPLC) assays. Significant differences in the total measurable metabolism of BP by the three microsomal enzyme incubations resulted from the use of the three assay procedures. Appreciable differences in the concentration of the metabolite fractions after 3-MC induction and TCPO inhibition are clearly demonstrated. NMR analysis revealed that while the 3-hydroxy-BP fraction is greater than 90% pure, the 9-hydroxy fraction contains a number of metabolites having essentially identical retention times.

Partial characterization of hepatic micorsomes from tupaia glis.

The dithionite difference spectrum of Tupaia microsomal cytochrome P-450-CO complex has an absorbance maximum at 449 nm, rather than at 450 nm as found for rat, rabbit, mouse, guinea pig, and human microsomes. N-octylamine difference spectroscopy showed the ratio of high- and low-spin forms of cytochrome P-450 to be different from that of the rat, indicating that the 449 nm absorption maximum might be due to a high concentration of the high-spin form, cytochrome P-448. The Tupaia microsomes demonstrated greater aryl hydrocarbon activity than microsomes prepared from male rats. These preliminary results suggest that Tupaia microsomes contain a modified terminal oxygenase which is responsible for the observed rapid metabolism of benzo[alpha]pyrene.