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Trehalase activity was determined in serum, liver, and kidney in alloxan treated Swiss mice and in homozygous (Ob/Ob, Db/Db) and heterozygous (Ob/+, Db/m+) diabetic mice. Both alloxan and genetic diabetic mice exhibited a large increase in serum and liver trehalase activity with no change in kidney trehalase activity. The heterozygotes (Ob/+, Db/m+) showed only a slight increase of enzyme activity. Further quantitative differences were noticed between the genetic and alloxan diabetic animals. The liver enzyme activity increased from 10- to more than 20-fold in the liver of the homozygous Ob/Ob and Db/Db strains and only 3-fold (not significant compared to controls) in the alloxan treated animals. The above results suggest a regulatory relationship between the genes coding for trehalase and the enzymes of glucose metabolism activity involved in the development of the metabolic anomalies of diabetes. The structural gene for trehalase may well have survived elimination of selective pressure during phylogenesis and remained part of a co-regulated group of glucose metabolising enzymes. This could explain its sensitivity to mutations affecting glucose metabolism and its sensitivity to insulin directed regulatory mechanisms. [ABSTRACT FROM PUBLISHER]

The prevalence of respiratory allergies has increased over the last 20 years, highlighting the need for a simple and noninvasive tool to investigate, in a clinical and epidemiological context, airway-inflammation mechanisms encountered in allergic and inflammatory processes. The nose, as the first region of the respiratory tract to come in contact with airborne pollutants, is easily explored with the use of nasal lavage (NL). We evaluated an NL method for adults and children, along with its reproducibility and capacity to separate different subgroups. NL reproducibility, assessed in 10 healthy, nonsmoking adults on three different occasions, was determined with the use of the intraclass coefficient of correlation for such inflammatory markers as total cell count, albumin, urea, neutrophil elastase, alpha(1)-antitrypsin, interleukin-6, and interleukin-8. Using this NL method, we analyzed nasal markers of 50 healthy adults (smokers and nonsmokers) and 12 healthy children. Our NL method demonstrated high reproducibility with regard to total cell count, albumin, urea, and alpha(1)-antitrypsin (intraclass correlation coefficient > 0.75). Compared with NL results in nonsmokers, NL in heavy smokers revealed significant increased concentrations of total cell counts and interleukin-8 and significant decreased concentrations of interleukin-6. These findings suggest that NL can be used as a tool in the assessment of inflammation because it has the correct reproducibility and can discriminate between heavy smokers and nonsmokers. Moreover, the use of this standardized method in children is feasible.

French researchers from the Building Scientific and Technical Center have produced a traffic-exposure index. To achieve this, they used an air pollution dispersion model that enabled them to calculate automobile pollutant concentrations in front of subjects' residences and places of work. Researchers used this model, which was tested at 27 Paris canyon street sites, and compared nitrogen oxides measurements obtained with passive samplers during a 6-wk period and calculations derived from the model. There was a highly significant correlation (r = .83) between the 2 series of values; their mean concentrations were not significantly different. The results suggested that the aforementioned model could be a useful epidemiological tool for the classification of city dwellers by present-or even cumulative exposure to automobile air pollution.

To evaluate the usefulness of tobacco markers in dependent smokers being treated with transdermal nicotine patches, a study was conducted at the Tobacco Withdrawal Consultation Centre at the Hôpital Laennec, Paris, France. 125 patients were included in the study and, in a first time, carbon monoxide in exhaled air, carboxyhaemoglobin, urinary nicotine and cotinine, Fagerström index, were measured and correlated to the amount of nicotine inhaled per day. The most significant value was observed for cotinine. In a second time, 25 patients were followed clinically and biologically with urinary continine monitoring (group FC) and 73 were followed up only clinically (group FC). The success rate of therapy 12 weeks after the end of treatment was 72% in group FB and 28% in group FC. The nicotine patch dose was positively correlated (p < 0.01) with successful outcome. The lower the urinary cotinine level at 4 weeks, the more likely was successful outcome (p < 0.05). If psychological factors remain important, urinary cotinine monitoring in the course of nicotine patch treatment thus favours successful withdrawal.

The mutagenicity of a new anthracycline (moflomycin) with potent antileukemic activity was studied by the Ames test in four strains of Salmonella typhimurium (TA97a, TA98, TA100 and TA102), and compared to the mutagenicity of doxorubicin, widely used as antineoplastic agent. Unlike doxorubicin, moflomycin displayed no mutagenic activity in strains TA98 and TA100. Low mutagenicity was only observed in TA102 strain and was not enhanced after metabolic activation. This result indicates that moflomycin induce mutagenicity by reverting base-pair substitution. The structural changes in the sugar moiety may be involved in the reduced mutagenicity of moflomycin. The low mutagenicity of moflomycin shown in this study enhances the potential advantage of this new derivative which displays a high antileukemic activity.

The mutagenic activity of the condensates from oxydative pyrolysis of various polyamides at 500, 800 and 1,000 degrees C has been searched for by AMES preincubation test in strains TA 98 and TA 100 with or without metabolic activation by an Aroclor 1254 induced rat liver microsomal S9mix fraction. All condensates are mutagenic in the presence of this fraction and most of them are far less or not mutagenic in the absence of S9mix. Strain TA 98 is more sensitive than strain TA 100 for detecting the mutagenic activity of these condensates. So, they mainly contain indirect mutagenic substances responsible for frameshift mutation. In all cases, mutagenic activity is maximum at 800 degrees C. This observation should draw the attention upon the genotoxic (carcinogenic) long term risk induced by thermal decomposition of plastics and then upon the necessary protection of firemen and others in charge of domestic or hospital solid waste incineration.

A cohort study of 29 nurses who extensively handle cytostatic drugs, 29 controls matched on sex and age, and seven patients under chemotherapy was carried out between 1983 and 1985. In a first study, urinary mutagenicity assays performed with the Ames test towards Salmonella typhimurium TA 98 with and without S9 mix gave an increased mutagenic activity, although not significant, for nurses as compared to controls, after adjustment on smoking habits. The results of mutagenicity assays for patients were significantly higher (P less than 0.01) than for non-smoker nurses and non-smoker controls with TA 98 without S9 mix. Of the 29 pairs, complementary assays were performed for non-smokers, that is 11 nurses and 11 matched controls, with TA 98, TA 100 and TA 1535 +/- S9 mix. A significant increase in mutagenic activity (P less than 0.05) was detected for nurses as compared to matched controls towards TA 98 with and without S9 mix. Moreover, the mutagenicity was significantly increased (P less than 0.05) in nurses who handled at least one electrophilic agents as compared to nurses who handled non-electrophilic drugs towards TA 98 with and without S9 mix.

The mutagenic potencies of 13 bromoethyl esters of natural organic acids, have been studied, by Ames's test (strains TA 98 and TA 100, with and without system of metabolisation, S9 mix). None of the 8 bromoethyl esters of linoleic, oleic, palmitic, stearic, lauric, myristic, cinnamic and fumaric acids is genotoxic. On the other hand the 5 others derived from gallic, oxalic, tartric acids (strain TA 100 with and without S9 mix), malic and citric acids (strain TA 100 with S9 mix) are mutagenic, the ester of gallic acid giving still a doubtful mutagenic response; their mutagenic potencies are 2 to 3 times smaller than that of bromo-2 ethanol. This observation, complemently with the mutagenicity of some organic esters of the chloro-2 ethanol, proves the potential danger of ethylene oxide used for the fumigation of foods or vegetables and medicinal plants containing much chloride and/or bromide.