Detection, amplification & sequence homology of sodC in clinical isolates of Salmonella sp.

Background & objectives: Periplasmic copper and zinc superoxide dismutase (Cu,Zn-SOD or SodC) is an important component of the antioxidant shield which protects bacteria from the phagocytic oxidative burst. Cu,Zn-SODs protect Gram-negative bacteria against oxygen damage which have also been shown to contribute to the pathogenicity of these bacterial species. We report the presence of SodC in drug resistant Salmonella sp. isolated from patients suffering from enteric fever. Further sodC was amplified, cloned into Escherichia coli and the nucleotide sequence and amino acid sequence homology were compared with the standard strain sSalmonella Typhimurium 14028. Methods: Salmonella enterica serovar Typhi (S. Typhi) and Salmonella enterica serovar Paratyphi (S. Paratyphi) were isolated and identified from blood samples of the patients. The isolates were screened for the presence of Cu, Zn-SOD by PAGE using KCN as inhibitor of Cu,Zn-SOD. The gene (sodC) was amplified by PCR, cloned and sequenced. The nucleotide and amino acid sequences of sodC were compared using CLUSTAL X. Results: SodC was detected in 35 per cent of the Salmonella isolates. Amplification of the genomic DNA of S. Typhi and S. Paratyphi with sodC specific primers resulted in 519 and 515 bp amplicons respectively. Single mutational difference at position 489 was observed between the sodC of S. Typhi and S. Paratyphi while they differed at 6 positions with the sodC of S. Typhimurium 14028. The SodC amino acid sequences of the two isolates were homologous but 3 amino acid difference was observed with that of standard strain S. Typhimurium 14028. Interpretation & conclusions: The presence of SodC in pathogenic bacteria could be a novel candidate as phylogenetic marker.

Study of molecular mechanism of cardiac injury induced by adriamycin / 中国临床药理学与治疗学

AIM: To preliminarily study the molecular mechanism for the cardiac injury in rat by adriamycin and the mechanism for the acute repair in the body. METHODS: The male Sprague Dawley rats were randomly divided into four groups (n=10 in each): The first group was kept without treament and served as the control ;the second, the third and the fourth received ADR in different doses (10, 20, 40 mg?kg -1 , respectively) by injection of adriamycin. The content of malondialdehyde (MDA)in the serum was estimated with thiobarbituric acid. Cu Zn SOD was measured by its reaction with xanthine oxidase. GSH was measured by its reaction with 5, 5 nitrobenzoic acid. Using semi quantitative reverse transcription polymerase chain reaction (RT PCR),we analyzed the expression of the associated gene. RESULTS: MDA contents in the medium and high ADR dose groups were higher than that in the control group (P

Effects of the pretreatment of free radical scavengers on the expression of apoptosis after gamma-irradiation in the rat parotid gland / 대한해부학회지

Apoptosis is a distinct morphological form of programmed cell death during growth, development and some diseases. Also, it is well known that the apoptosis is usually caused by carcinogens, drugs, heat and radiation in mature cells. Especially, the therapeutic radiation of the head and neck region may cause xerostomia after irradiation. Recently, there are many trial reports to explain the radiation cell death to the acute cellular changes as a programmed cell death. The author performed present study to investigate the potential role of reactive oxygen metabolites as a signal for radiation-induced apoptosis. A series of free radical scavengers, allopurinol, superoxide dismutase, dimethylthiourea were pretreated before gamma-irradiation for evaluating their ability to block apoptosis in the rat parotid gland in vivo, and the light microscopic results were evaluated and analyzed using the Tdt-mediated dUTP-biotin nick end labeling technique. The results were as follows. 1. Under the light microscope, irradiation induced apoptotic bodies in the parotid gland were revealed the intensively positive reaction on the TUNEL technique, and most apoptotic bodies were confined in the acinar system, there were rare apoptotic changes in the ductal system. 2. In all irradiated experimental groups without antioxidants pretreatment, the number of the apototic bodies was the greatest in post-irradiation 24 hour group, and then decreased as a function of time. 3. As a result on pretreatment of allopurinol that effectively inhibit xanthine oxidase before irradiation, failed to block the irradiation-induced apoptosis in the rat parotid gland. Moreover, in the postirradiation 1 day group, the apoptotic expression and destruction of the acini increased than non-irradiated experimental group. 4. As a result on pretreatment of Cu/Zn-SOD that contributes to extracellularly generated superoxides and dimethylthiourea to scavenge the hydroxyl free radicals before irradiation, two antioxidants inhibit the irradiation-induced apoptosis (P<0.001), salivary acinar structures remained intact. 5. To evaluate the synergistic effects, simultaneous pretreatments of allopurinol and Cu/Zn-SOD, Cu/Zn-SOD and DMTU were conducted. Expression of irradiation-induced apoptosis was lower than the experimental groups which not pretreated any antioxidants (P<0.001), but there was no synergism of two antioxidants. 6. Irradiation-induced apoptotic bodies crowded at the outer cortical layer including lymphatic nodules, and the aspect of apoptotic expression in the lymph node took place earlier than in the salivary acini. Taken all together, it is forecasted that the irradiation-induced apoptosis of the parotid gland is a result of primary cellular damage by oxygen or hydroxyl free radicals. Through this study, the facts that pretreatments of free radical scavengers block the irradiation-induced apoptosis were identified. But, oxygen free radicals were not produced via xanthine oxidase process, whereas, allopurinol that inhibits this reaction influenced the harmful effects on the parotid gland.

Effects of Cadmium on Superoxide Radical, Superoxide Dismutase, Catalase and ATPase Activity in Liver, Kidney and Testicle of Rats in Vtm and in Vivo / 예방의학회지

Production of free radicals of superoxide anion in tissues by cadmium, activities of superoxide dismutase and catalase to protect tissue damages caused by the free radicals and ATPase that plays an important role in energy metabolism at cellular level were investigated. Experiments in viro were conducted with liver, kidney and testicle tissue homogenates of rats adding 0.05~0.50 mM cadmium chloride, and in vivo experiments administering single dose of 5mg of cadmium/kg of body weight in 0.1% cadmium chloride solution intraperitoneally 48 hours prior to evisceration. Production of superoxide radicals in liver and testicle increased with addition of cadmium in vitro, but not in kidney. In vivo experiments, however superoxide radicals slightly increased in liver and kidney but not in testicle. Superoxide dismutase (Cu, Zn-SOD and Mn-SOD), catalase and ATPase (total, (Mg++)- & (Na+)- (K+)-) activity decreased in the presence of cadmium in dose dependent manner. Reduction of these enzyme activities varied not only with dosage of cadmium but also with type of tissue and between in vitro and in vivo experiment.