Factors associated with hypertension in Nigerian civil servants

BACKGROUND. Study of hypertension in segments of West African populations in transition toward Westernization may lead to better understanding of the high risk for hypertension among Westernized blacks. METHODS. Five hundred fifty-nine urban civil servants, ages 25-54, were recruited from six ministries of Bendel State, Nigeria. Blood pressure, physical measurements, urinary protein and glucose, fasting blood glucose, and demographic data were collected at the workplace. Subjects were classified as senior staff (professionals or administrators) or junior staff (non-administrators). RESULTS. Among 172 male senior staff, the age-adjusted rate of hypertension (diastolic blood pressure > or = 90 mm Hg, systolic blood pressure > or = 140 mm Hg, or on an antihypertensive medication) was 43% and occurrence rose dramatically from 21 to 63% across age groups 25-34 to 45-54, respectively. Among 266 male junior staff, the age-adjusted rate of hypertension was 23%, and occurrence did not rise with age. Logistic regression showed that body mass index (kg/m2), age, alcohol drinking, and being senior staff were all independently related to hypertension in men. On the other hand, the age-adjusted rate of hypertension in 121 women was 20% and was significantly related only to body mass index. CONCLUSION. Male urban civil servants appeared to have a risk for hypertension similar to that of U.S. black males. Age, body mass index, alcohol drinking, and other unidentified factors related to higher socioeconomic status were strong determinants of hypertension in this population.     

Inhibition by N-acetylcysteine of carcinogen-DNA adducts in the tracheal epithelium of rats exposed to cigarette smoke

The ability of the aminothiol N-acetylcysteine (NAC) to preventthe formation of carcinogen-DNA adducts in tracheal epithelialcells was investigated in Sprague-Dawley rats exposed whole-bodyto mainstream cigarette smoke for either 40 or 100 consecutivedays. ³²P-Postlabelling analyses showed the occurrence of DNAadducts (12.49 adducts/10⁸ nucleotides) after 40 days of exposure,with a trend to formation of characteristic diagonal radioactivezones. Total adduct levels were not further enhanced after 100days of exposure to smoke, although significant changes occurredin the amounts of individual adducts. NAC, given by gavage inthe 40 day study and in drinking water in the 100 day study,significantly inhibited the formation of smoke-related carcinogen-DNAadducts in the tracheal epithelium, to such an extent that adductlevels were not significantly higher than those detected insham-exposed control rats. Together with a variety of othermolecular, clastogenicity, metabolic, cytological and histopathologicalend-points investigated in rodents and with the preliminaryevidence arising from a study in humans, these results documentthe considerable efficacy of oral NAC in inhibiting smoke-relatedcarcinogen-DNA adducts.     

Preventive and therapeutic role of vitamin E in chronic plumbism

The ability of vitamin E to prevent or treat experimental lead intoxication was investigated in rats. Lead ingestion (10 mg/kg, lead as lead acetate, orally for 6 weeks) significantly inhibited the activity of blood delta-aminolevulinic acid dehydratase (ALAD), reduced the brain dopamine (DA) contents, enhanced the blood zinc protoporphyrin, and enhanced the urinary excretion of delta-aminolevulinic acid (ALA). Lead exposure also elevated brain norepinephrine, homovanillic acid, and 5-hydroxyindole acetic acid (5-HIAA) levels and concentration of lead in blood and tissue. Simultaneous supplementation of vitamin E along with lead significantly reduced the inhibition of blood ALAD activity, brain DA and 5-HIAA levels, and elevation of urinary ALA excretion. Blood and liver lead concentrations were also significantly reduced by simultaneous supplementation with vitamin E. Postlead exposure treatment with vitamin E was ineffective in reducing the lead-induced effects, except that the inhibition of blood ALAD activity was slightly reduced. The present results suggest that vitamin E given simultaneously with lead is effective in reducing the severity of lead intoxication.     

Physical assessment of heat insulation rescue foils

For the insulation of hypothermic individuals, aluminium-coated foils are used as rescue blankets and rescue suits, respectively. By measurements on a phantom, the efficiency of these foils was tested. Based on an appropriate physical model results were transferred to the thermal reaction of hypothermic individuals. Following investigations were carried out: rescue foil with different types of clothing, comparison between rescue foil and woolen blanket, "Hibler packing", rescue suit at sudden fall in temperature. Applying these foils and the suit, respectively, a thermal stabilization of the body core is being achieved approximately under realistic conditions. When applying the "Hibler packing", reheating is achieved both with wet and dry clothing.     

Enhanced metabolic activation of chemical hepatocarcinogens in woodchucks infected with hepatitis B virus

The metabolism of chemical carcinogens was investigated in liverpreparations from 28 captive woodchucks (Marmotamonax). Of these,23 were naturally infected with the wood-chuck hepatitis virus(WHV), and eight also had primary hepatocellular carcinoma (PHC).Twenty-nine parameters were investigated in liver subcelhilarfractions, including cross-reactivity with HBsAg, and biochemicalparameters, such as -glutamyl transpeptidase, cytochrome P-450and mirosomal monooxygenases (aryl hydrocarbon hydroxylase,ethodycoumarin and ethoxyresorufin deethylases, amino-pyrineand dimethylnitrosamine demethylases, and testosterone 7-and16ß- and 6ß-hydroxylases), uridine 5'-diphos-phoglucuronosyltransferase, GSH and related enzymes (peroxidase, reductaseand S-transferase), as well as other cytosolic enzyme activities(glucose 6-phosphate and 6-phosphogluconate dehydrogenases,NADPH- and NADH-dependent diaphorases, and DT diaphorase). Inaddition, liver preparations were used in order to quantifythe metabolic activation into bacterial mutagens of five procarcinogens(aflatoxin B¹, the pyrolysis products Trp-P-2 and MelQ, 2-aminofluoreneand dimethylnitrosamine) and the decrease of potency of threedirect-acting mutagens (sodium di-chromate, ICR 191 and 4-nitroquinoline1-oxide). WHV infection produced a significant stimulation ofcarcinogen metabolism, as shown by the simultaneous change indetoxification parameters (GSH depletion) and activation indices(enhancement of microsomal monooxygenases and of pro-carcinogenactivation into mutagenic metabolites). There were no significantdifferences between WHV-positive samples from animals, withoutPHC and the noncancerous tissue of PHC-bearing animals, whereasa decrease of both activation and detoxification indices wasrecorded in the turmorous tissue. There was a considerable interindividualvariability among WHV carriers, which was tentatively ascribedto genetic factors. Pregnancy was the only known factor influencingthe results in WHV carriers. However, even by excluding pregnantanimals, the effects on carcinogen metabolism produced by WHVinfection were still statistically significant. These results,together with previous data obtained in humans, revealed thatmetabolic factors may play a role in the synergism between viralhepatitis and chemical hepato-carcinogens in the etiopathogenesisof PHC.