Inhibition by acarbose, nojirimycin and 1-deoxynojirimycin of glucosyltransferase produced by oral streptococci

Acarbose is known to inhibit glucoamylase, maltase and sucrase. Our aim was to test whether it would also inhibit glucosyltransferase (GTF), to determine the type of inhibition and to compare the inhibitor potency of acarbose with that of nojirimycin and deoxynojirimycin, two other glucosidase inhibitors. Enzyme inhibition was measured either by chemical assay or by incorporation of radioactivity into product. Acarbose effectively inhibited the synthesis of polysaccharide by GTF from strains of Streptococcus mutans and Streptococcus sanguis, but not by fructosyltransferase from Streptococcus salivarius. Acarbose and 1-deoxynojirimycin were more potent inhibitors of GTF than maltose, nojirimycin or various amino sugars. The mechanism of action of these compounds is consistent with competitive inhibition.     

Urinary tract infection and risk of bladder cancer

In an epidemiologic study of 2982 bladder carcinoma patients and 5782 population controls from 10 geographic areas of the United States, the role of urinary tract infection and inflammation in the etiology of this neoplasm was evaluated. A history of urinary tract infection significantly elevated the risk of bladder cancer, particularly in individuals who reported three or more infections (relative risk (RR) = 2.0). Significantly increased bladder cancer risk was also found for bladder stones (RR = 1.8), while kidney stones showed no relation. A history of three or more urinary tract infections was strongly related to squamous cell carcinoma in particular (RR = 4.8).     

Effects of timing and type of tobacco in cigarette-induced bladder cancer

We analyzed a case-control study of bladder cancer in Torino (512 male and 55 female cases; 596 male and 202 female controls) with emphasis on the timing of cigarette smoking and the use of black or blond tobacco. The risk of bladder cancer was 2 to 3 times higher among smokers of black tobacco than among smokers of blond tobacco. Both groups of smokers showed a beneficial effect of smoking cessation, with an immediate decline in risk. This pattern is consistent with a late-stage effect of smoking. Among smokers of black tobacco, there was a gradient of risk with early exposure, and smokers who had quit never showed a drop to base-line levels of risk. These patterns, not apparent in users of blond tobacco, suggest an early stage effect of black tobacco, perhaps due to the higher concentration of aromatic amines in black than blond tobacco smoke and the higher blood levels of the hemoglobin adduct with 4-aminobiphenyl (a human bladder carcinogen) among smokers of black tobacco.     

Predictive value of, and observer variability in, several ways of reporting antepartum cardiotocographs

Summary. Each of three scoring systems, and oscillatory frequency, had significantly poorer correlation with fetal outcome than reporting the cardiotocograph (CTG) as either 'reactive' or 'non-reactive'. There was no significant difference in the intra- and inter-observer variability when the CTG was reported in this way.     

Use of naloxone in septic shock

Experimental and clinical evidence show that endogenous opiates (endorphins) contribute to the pathophysiology of circulatory shock. The authors evaluated the effectiveness and safety of continuous infusion of naloxone in five septic patients with prolonged hypotension unresponsive to volume replacement and dopamine infusion. Naloxone (2 mg bolus) was intravenously administered and continued at 0.25 mg/hr for 24 to 48 hours. All five patients had significant increase in mean arterial pressure of between 20 and 30 mmHg (P less than 0.0012). Cardiac index, systemic vascular resistance, and pulmonary arterial pressure were not significantly altered; however, there was a significant difference in pulmonary capillary wedge pressure (P less than 0.034) and urinary output (P less than 0.0273). Subjects did not experience side effects with naloxone. We conclude that continuous infusion of naloxone can reverse endorphin-mediated hypotension in septic shock patients.     

Symptoms of tobacco withdrawal from total cigarette cessation versus partial cigarette reduction

The study examined the occurrence of acute tobacco withdrawal symptoms among three methods of smoking cessation. Smokers were asked to smoke ad lib for 3 days and then randomly assigned to one of three groups for the next 5 days: (1) total cigarette cessation; (2) 50% reduction of number of cigarettes; or (3) reduction of nicotine yield of cigarettes. Of the 13 measures of tobacco withdrawal, six of the measures showed significant differences in severity of withdrawal symptoms between the total cessation group and partial reduction groups. There were no significant differences in severity of withdrawal between the two partial reduction groups. Offprint requests to: D.K. Hatsukami