Beneficial effects of yam on carbon tetrachloride-induced hepatic fibrosis in rats.

BACKGROUND: In a previous study, lyophilised yam reduced brain amyloid beta-protein (Abeta) accumulation and improved the antioxidative defence system in senescence-accelerated (SAMP8) mice. Therefore, the aim of this study was to investigate the hepatic protection of yam in the carbon tetrachloride-induced hepatic fibrosis of rats. Hepatic fibrosis was induced in rats via intraperitoneal injections of CCl(4) at a dose of 1 mL kg(-1) body weight (BW) twice weekly for 8 weeks. Three groups of rats were gavaged daily with yams at doses of 0.5, 1 and 2 g kg(-1) BW for 8 weeks, respectively. RESULTS: Yam treatments significantly decreased the ratio of liver/body weight, levels of gamma-glutaminotranspeptidase (GGT), low-density lipoprotein, and triglyceride in serum when compared with those administered CCl(4) alone. Treatment with yams significantly elevated antioxidant activities of glutathione peroxidase (GSH-Px) and superoxidase dismutase (SOD) in livers. Microscopically, yam-treated groups presented with low histoscores of CCl(4)-induced liver injury and fibrosis. Additionally, yam treatment reduced the area of GGT-positive foci and the index of proliferating cell nuclear antigen (PCNA) in liver. CONCLUSION: Daily administration of yam attenuates CCl(4)-induced hepatic fibrosis in rats in a dose-dependent manner; this attenuation may be related to the antioxidant properties of yams.

[Analysis of antimicrobial resistance of Streptococcus pneumoniae with restriction fragment length polymorphism of pbp2b gene and pulsed-field gel electrophoresis profiles among children].

UNLABELLED: Streptococcus pneumoniae is a common cause of potentially life-threatening infections such as meningitis, bacteraemia, pneumonia worldwide, for which children of preschool age are at particularly high risk. Since the late 1970s and 1980s, antibiotic resistance among pneumococci has become an emerging problem. Several multidrug-resistant clones have rapidly spread throughout the world. OBJECTIVE: (1) To investigate the prevalence of penicillin and other antibiotics nonsusceptibility among pneumococci. (2) To analyze the correlation of pbp2b amplicon profiles with penicillin resistance. (3) To serotype 31 isolates of penicillin-resistant pneumococci by latex agglutination. (4) To analyze the chromosomal relatedness of serotype 23F and 6 isolates of penicillin-resistant pneumococci by using pulsed-field gel electrophoresis (PFGE) and characterize these isolates in molecular epidemiology. METHODS: (1) Susceptibility was determined by using broth microdilution, E-test, and K-B disk. (2) The correlation of pbp2b amplicon profiles with penicillin resistance was assessed by restriction fragment length polymorphism (RFLP). (3) Serotyping of penicillin-resistant pneumococcal isolates was performed by using latex agglutination. (4) The properties of serotype 23F and 6 isolates of penicillin-resistant pneumococci were assessed by PFGE. RESULTS: S. pneumoniae with increased nonsusceptibility (including intermediate strains and resistant strains) to penicillin G was 9.9% in 1997, 12.6% in 1998, 14.6% in 2000; to cefuroxime 4.2%, 1.5%, 8.2%; to cefotaxime 0.0%, 1.7%, 1.0% respectively. There were no statistically significant differences (P > 0.05). While resistance to erythromycin, trimethoprim-sulfamethoxazole and chloramphenicol increased significantly from 76.8% in 1997 to 87.4% in 2000, from 74.7% to 88.3%, and from 22.6% to 40.8%, respectively (P < 0.05). RFLP analysis of pneumococcal pbp2b-specific amplicons was effective for screening penicillin resistance. Of the 31 strains of penicillin-resistant pneumococci (MICs 0.12 - 2.0 micro g/ml) studied, 6 (19.4%) strains (MICs 0.12 - 0.19 micro g/ml) were serotype 23F and 3 (9.7%) strains (MICs 0.5 - 1.5 micro g/ml) were serotype 6. There were nearly identical susceptibility to antibiotics and identical PFGE patterns in the former, and there were different susceptibility to antibiotics and different PFGE patterns in the latter. Three serotype 6 strains had different susceptibility to antibiotics and different PFGE patterns, which suggested that those strains may be scattered. CONCLUSION: Generally beta-lactams retained their activity against S. pneumoniae in Beijing. Resistance to erythromycin, trimethoprim-sulfamethoxazole, and chloramphenicol increased drastically. RFLP analysis of pneumococcal pbp2b-specific amplicons was effective for screening penicillin resistance. In 6 strains of serotype 23 F there were nearly identical susceptibility to antibiotics and identical PFGE patterns, which suggested the probability that there was a spread of serotype 23F isolates with low-level penicillin resistance in local area.

Determination of eukaryotic peptidyltransferase activity by pseudo-first-order kinetic analysis.

We have developed an in vitro system for the determination of peptidyltransferase activity in rabbit reticulocyte ribosomes. Using this system, a detailed kinetic analysis of a model reaction for peptidyltransferase is described, with AcPhe-tRNA as the peptidyl donor and puromycin as the acceptor. The [AcPhe-tRNA-poly(U)-80S ribosome] complex (complex C) is isolated and then reacted with excess puromycin to give AcPhe-puromycin. This reaction (puromycin reaction) follows first-order kinetics at all concentrations of puromycin tested. At saturating concentrations of puromycin, the first-order rate (k3) constant is identical to the catalytic rate constant (kcat) of peptidyltransferase. This k3 of peptidyltransferase is equal to 2.9 min-1 at 37 degrees C. Moreover, the ratio k3/ Ks, which is an accurate measure of peptidyltransferase activity, was increased 80-fold when salt-washed ribosomes were replaced by unwashed ribosomes. Finally, the puromycin reaction was inhibited by several well-known antibiotics acting on the eukaryotic peptidyltransferase.

Serum enzyme abnormalities in protein energy malnutrition.

Six serum enzymes, alkaline phosphatase, cholinesterase, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase and gamma-glutamyl transpeptidase were studied in 30 cases of protein energy malnutrition (PEM). The mean serum values of alkaline phosphatase, cholinesterase and lactate dehydrogenase in cases of PEM were significantly lower than the controls, lowering being maximum in PEM Grade IV. The mean serum values of aspartate aminotransferase and alanine aminotransferase in patients with PEM were significantly higher than the controls. The mean serum values of gamma-glutamyl transpeptidase showed similar significant rise in all but PEM Grade IV. The degree of increase in the serum values of these three enzymes were maximum in cases with PEM Grade I. These findings suggest that abnormalities in blood levels of these enzymes occur in any form of PEM and these are related to the severity of the disease.

Possible ranitidine hepatitis.

A 63-year-old woman developed anicteric hepatitis after two weeks of therapy with ranitidine. Despite continuation of therapy, her symptoms resolved within five days and transaminase levels returned to normal in the next four weeks, at which time use of the drug ceased. The gamma-glutamyl transpeptidase level returned to normal two weeks later. Although liver biopsy and drug rechallenge were not performed, no other cause for the reaction could be found.

A new colorimetric method for the determination of serum enzyme, gamma-glutamyl transpeptidase, cystine aminopeptidase, and leucine aminopeptidase.

A new colorimetric method for the serum enzyme assay was developed, using the color reaction of a ferrous salt complex and a primary aromatic amine. For this method new substrates containing primary aromatic amines were synthesized. The aromatic amine liberated by the enzyme reaction was measured by its color reaction with pentacyanoammineferroate treated with hydrogen peroxide. The determination was made at a wavelength of around 700 nm, at which the assay is not affected by colored substances in serum. Therefore a blank assay was not necessary. This method was applied to the assay of serum gamma-glutamyl transpeptidase, cystine aminopeptidase, and leucine aminopeptidase. The results obtained were in good agreement with those of the p-nitroanilide method also used to assay each enzyme. This new method can be used on a Technicon autoanalyzer system.

Immunoglobulins in persons with long-term exposure to halothane.

In 18 persons (anaesthetists and anaesthetic nurses) with a history of long-term exposure to low concentrations of halothane the activity of aminotransferases, GGTP, and alkaline phosphatase, the bilirubin level and thymol turbidity test were determined and no significant abnormalities were found. On the other hand, determinations of immunoglobulons showed changes in the raised IgM level in 15 out of 18 persons, the difference between the normal level and that found in the present studies being statistically significant. The levels of IgA and IgG were within the normal range. Raised IgM level may be due to stimulation of the immune system by halothane.

Serum enzyme levels in anaesthetic personnel.

The reported studies were carried out on 22 persons, 15 anaesthetists and 7 anaesthetic nurses with a history of long-term exposure to halothane in low concentrations. The activity of gamma-glutamyl-transpeptidase (GGTP) and aminotransferases, the level of bilirubin and thymol turbidity test were determined. No significant abnormalities were found in the mean values of these determinations. In some cases a rise in alkaline phosphatase activity and in two cases a rise of GGTP were found. The results are not suggesting the presence of hepatocellular damage in this group.