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981.
The high level expression and purification of rat monoamine oxidase B (rMAOB) in the methylotrophic yeast Pichia pastoris is reported. Nearly 100 mg of purified rMAOB is obtained from 130 g (wet weight) of cells (0.5 L of culture). The MALDI-TOF mass spectrum of the purified protein shows a single species with a molecular mass of 59.228 ± 0.064 kDa, which agrees with the calculated molecular weight of 59.172 kDa for the rMAOB protein sequence assuming one mole of covalent FAD per mole of the enzyme. Consistent with the MALDI-MS data, purified rMAOB shows a single band near 60 kDa in Coomassie-stained SDS–PAGE gel as well as on Western blot analyses performed using antisera raised against human MAOA and BSA-conjugated FAD. A partial amino acid sequence of the purified protein is confirmed to be that of the wild type rMAOB by in-gel trypsin digestion and MALDI-TOF-MS analyses of the liberated peptide fragments. Steady state kinetic data show that purified rMAOB exhibits a Km(amine) of 176 ± 15 μM and a kcat of 497 ± 83 min−1 for benzylamine oxidation, and a Km(O2) of 170 ± 10 μM. Kinetic parameters obtained for purified rMAOB are compared with those reported earlier for recombinant human liver MAOB expressed in P. pastoris. 相似文献
982.
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985.
Yoshikawa M Nishiofuku M Moriya K Ouji Y Ishizaka S Kasahara K Mikasa K Hirai T Mizuno Y Ogawa S Nakamura T Maruyama H Akao N 《Parasitology international》2008,57(4):525-529
We present 3 adult cases of visceral toxocariasis from the same family, who each consumed thin slices of raw bovine liver weekly, and developed eosinophilia and multiple small lesions in their livers and lungs. Serological examinations using the larval excretory–secretory product of Toxocara canis strongly indicated infection with Toxocara species larvae. The patients responded well to treatment with albendazole. Ingestion of raw liver from paratenic animals is considered to be a common transmission route of human toxocariasis, especially in adults. 相似文献
986.
Alcoholic liver disease (ALD) is one of the most common diseases in modern society. A large number of studies are in progress
aiming to identify natural substances that would be effective in reducing the severity of ALD. Although there are currently
a number of drugs on the market, their long-term use can have numerous side effects. Hemidesmus indicus is an indigenous Ayurvedic medicinal plant used in soft drinks in India. In this study, we examined the effects of its ethanolic
root extract on experimental liver damage in order to evaluate its hepatoprotective effects against hepatotoxicity induced
in rats by ethanol at a dosage of 5 g/kg body weight for 60 days. The H. indicus root extract was given at a dose of 500 mg/kg body weight for the last 30 days of the experiment. The animals were monitored
for food intake and weight gain. The liver was analysed for the degree of lipid peroxidation using thiobarbituric acid reactive
substances (TBARS) and antioxidant status using the activities of glutathione-depedendant enzymes. The degree of liver damage
was analysed using serum marker enzyme activities, the total protein, albumin, globulin, ceruloplasmin and liver glycogen
contents, and the A/G ratio. The Fourier transform infrared spectra (FT-IR) of the liver tissues were recorded in the region
of 4000–400 cm−1. The ethanol-fed rats showed significantly elevated liver marker enzyme activities, lipid peroxidation levels and reduced
antioxidant levels as compared to the control rats. Oral administration of H. indicus for the latter 30 days resulted in an increased food intake and weight gain, decreased TBARS levels, near normal levels of
glutathione-dependent enzymes, increased total protein, albumin, globulin and liver glycogen contents, an increased A/G ratio,
and decreased liver marker enzyme activities and ceruloplasmin levels. The relative intensity of the liver FT-IR bands for
the experimental groups were found to be altered significantly (p < 0.05) compared to the control samples. For the group that
had H. indicus co-administered with ethanol, the intensity of the bands was near normal. Moreover, the results of the FT-IR study correlated
with our biochemical results. 相似文献
987.
988.
Xiao Y Word B Starlard-Davenport A Haefele A Lyn-Cook BD Hammons G 《Cell biology and toxicology》2008,24(3):265-272
DNA methylation is catalyzed by a family of DNA methyltransferases (DNMTs) including the maintenance enzyme DNMT 1 and de
novo methyltransferases DNMT 3a and DNMT 3b. Elevated levels of DNMTs have been found in cancer cells and in several types
of human tumors. A polymorphism found in DNMT3b has been associated with increased risk for several cancers. The factors influencing
DNMT expression in human tissues have not been clearly determined. he present study examined TDNMT3a and DNMT3b levels in
human liver tissue samples and compared the effect of ageing, cigarette smoking, and gender. DNMT3a and DNMT3b expression
levels in the samples from older individuals (56–78 years, n = 28) were both significantly higher than those of the younger group (16–48 years, n = 27) (73.2 ± 3.4 vs 8.3 ± 2.8 and 56.1 ± 1.9 vs 17.5 ± 5.7, respectively; p < 0.05). Levels of DNMT3b in females were significantly higher than those in males (75.4 ± 2.2 vs 16.3 ± 4.7; p < 0.05); however, DNMT3a levels were similar for females and males (52.7 ± 2.7 vs 48.4 ± 2.0). Expression levels of DNMT3a
and DNMT3b were similar in smokers and nonsmokers (58.1 ± 3.5 vs 60.8 ± 3.1 and 54.5 ± 2.3 vs 48.3 ± 1.8, respectively). Genotyping
for DNMT3b (C→T) variant in this sample pool showed a frequency distribution of CC (41%), CT (50%), and TT (9%). The findings
from this study suggest that ageing and gender may be important factors influencing DNA methylation status. 相似文献
989.
目的探讨提高小型猪胰腺十二指肠移植术麻醉管理的相关问题.方法供体和受体小型猪各20只,采用氯胺酮加咪唑安定进行基础麻醉,氯胺酮加依托咪酯维持麻醉;行平均颈内动脉压、中心静脉压及血气的监测.结果小型猪胰腺移植术中麻醉良好,受体的平均动脉压在吻合血管开放后有明显下降,与开放前有明显差异(P<0.05).中心静脉压和血气指标无明显变化.结论在小型猪胰腺移植麻醉手术中,充分补充血容量、加强循环系统的监测和管理,尤其是吻合血管开放后循环系统的管理对受体和移植胰腺的存活至关重要. 相似文献
990.
灵光注射液对失血性休克大鼠心脏和肝脏的影响 总被引:1,自引:1,他引:0
目的 观察灵光注射液 (复方樟柳碱 )对失血性休克再灌注大鼠心脏和肝脏损伤的影响。方法 将5 6只雄性大鼠随机分 4组 ,分别设为假休克组 (8只 )、模型组 (16只 )、灵光注射液低剂量组 (16只 )和高剂量组 (16只 ) ,除假休克组外 ,大鼠均经历 4kPa ,70min的失血性休克 ,在休克复苏后 6h和 12h各组分别处死半数动物 ,检测血清CK、CK MB、LDH、ALT、AST ,心脏和肝脏做组织学和超微结构检查。结果与结论 灵光注射液对大鼠失血性休克再灌注引起的心脏和肝脏功能和形态损伤均有明显的治疗作用 ,其机制可能与改善微循环、清除氧自由基和保护生物膜作用有关。 相似文献