葡萄糖和Cu2+对蛹虫草Cu,Zn超氧化物歧化酶在E.coli中表达的影响

对含有蛹虫草Cu，Zn-超氧化物歧化酶（cm—SOD）基因的重组E．coli培养条件进行了初步优化。结果表明，LB培养基中含有Cu^2＋可明显提高超氧化物歧化酶比活力；而在菌体培养中补加葡萄糖，可提高重组蛋白表达量和细胞生物量。在含有0．6mmol／L Cu^2＋、Zn^2＋的LB培养基中补加22mmol／L葡萄糖，每200ml培养液可获得1g湿细胞，超氧化物歧化酶比活力达到3305u／mg。     

Immunohistochemical study of the kidneys after severe muscular injury

Severe muscular injury sometimes causes renal failure, and myoglobin in skeletal muscle is known to induce toxic free oxygen radicals in the kidneys. The relationship between the immunohistochemical expression of myoglobin and the scavenger copper/zinc superoxide dismutase (Cu/Zn-SOD) was investigated in kidneys taken from two autopsy groups, a group with tourniquet shock (n = 4), and a group with severely injured skeletal muscle (n = 18). Paraffin-embedded kidney sections were used for immunohistochemical staining by the avidin-biotin-complex (ABC) method using antibodies against myoglobin and Cu/Zn-SOD. Detection of the two antigens was analyzed qualitatively. In most cases of tourniquet shock in which the survival time was considered to be relatively long, myoglobin staining was positive and Cu/Zn-SOD was negative. Among the seven cases of severely injured skeletal muscle in which the survival period was considered to be relatively short, positive staining was detected immunohistochemically for both myoglobin and Cu/Zn-SOD. Moreover, in most of the cases in this group that showed acute tubular necrosis, immunohistochemical staining was negative for both markers, whereas positive staining was found for most of the cases in which the kidneys were revealed to be normal by HE staining. These findings suggest that when myoglobin enters the kidneys via the circulation, Cu/Zn-SOD reacts to eliminate free radicals, but is depleted by consumption in the long run, and that there might be a relationship between these histological findings and immunohistochemical expression. Received: 2 December 1999 / Accepted: 22 May 2000     

Familial amyotrophic lateral sclerosis with bulbar onset and a novel Asp101Tyr Cu/Zn superoxide dismutase gene mutation

We describe a patient with familial amyotrophic lateral sclerosis (FALS) in whom we identified a novel missense mutation in exon 4 (Asp101Tyr) of the Cu/Zn superoxide dismutase (SOD1) gene. The disease started with a bulbar symptom (rapidly progressive hoarseness) and at autopsy showed degenerative changes restricted to the upper and lower motor neuron systems (more strictly, with lower motor predominance, showing the most severe degeneration in the nucleus ambiguus). Occasional intracytoplasmic Lewy-body-like hyaline inclusions that were immunoreactive for ubiquitin and SOD1, but immunonegative for neurofilament protein, were found in the lower motor neurons. This is the first report of hoarseness as the initial manifestation of FALS. This SOD1 gene mutation may be associated with a particular clinicopathological phenotype.     

Laser modification of the blood in vitro and in vivo in patients with Parkinson's disease

The effect of He-Ne laser radiation on activity of MAO B, Cu/Zn-SOD, Mn-SOD, and catalase in blood cells from patients with Parkinson's disease was studied in vivo and in vitro. The effects of intravenous in vivo irradiation (intravenous laser therapy) were more pronounced than those observed in similar in vitro experiments. It is concluded that generalized effect of laser therapy involves interaction between blood cells.     

Preventive effect of melatonin on the progression of alpha-naphthylisothiocyanate-induced acute liver injury in rats

The preventive effect of melatonin on the progression of alpha-naphthylisothiocyanate (ANIT)-induced acute liver injury with cholestasis was examined in rats treated once with the hepatotoxin [75 mg/kg body weight (BW), i.p.]. In rats treated with ANIT alone, liver injury with cholestasis occurred 24 hr after treatment and progressed at 48 hr, judging from the serum levels of hepatobiliary marker enzymes and components. Melatonin (10 or 100 mg/kg BW) was orally administered to the ANIT-treated rats, 24 hr after the hepatotoxin treatment at which time hepatic injury had already developed. The administered indoleamine prevented the progression of liver cell damage rather than biliary cell damage more effectively at the higher dose than at the lower dose. In rats treated with ANIT alone, the serum and hepatic concentrations of thiobarbituric acid reactive substances, an index of lipid peroxidation, and the hepatic activity of myeloperoxidase, an index of tissue neutrophil infiltration, increased 24 hr after treatment and further increased at 48 hr. In the liver of rats treated with ANIT alone, Cu,Zn-superoxide dismutase activity decreased 24 hr after treatment and was further reduced at 48 hr, although there was no change in Mn-superoxide dismutase activity. Catalase and Se-glutathione peroxidase activities also decreased at 48 hr, while reduced glutathione concentrations remained increased at 24 and 48 hr. The melatonin administered to the ANIT-treated rats attenuated the increases in serum and hepatic concentrations of thiobarbituric acid reactive substances and the decreases in hepatic activities of Cu,Zn-superoxide dismutase, catalase, and Se-glutathione peroxidase found at 48 hr after the hepatotoxin treatment more effectively at the higher dose than at the lower dose; on the other hand, melatonin treatment had no effect on the increases in hepatic myeloperoxidase activity and reduced glutathione concentration found at 48 h. These results indicate that orally administered melatonin at pharmacological doses prevents the progression of ANIT-induced acute liver injury, mainly liver cell damage, in rats, and suggest that the administered melatonin exerts these preventive effects through its direct and indirect antioxidant actions.     

ICP-MS法测定高钙食品中铅、镉、砷、铜的研究

目的：研究溶液中高含量钙的基体效应及降低基体干扰的方法,建立ICP-MS测定高钙食品中铅、镉、砷、铜含量的分析方法。方法：样品采用微波消解,通过研究功率和载气流速在不同钙基体含量时对铅砷铜镉测定的影响,结合调谐液优化仪器工作参数,选择合适的内标元素对钙基体干扰进行校正。结果：高钙食品中钙基体含量不超过0.1%,在90 min内连续进样引起的基体干扰基本上得到克服。各元素加标回收率均在86%-99%,标准偏差均低于3.5%。结论：方法准确可靠,适用于高钙食品中铅、镉、砷、铜含量的同时测定。     

Serum trace elements and Cu/Zn ratio in breast cancer patients

Serum copper, zinc, and the Cu/Zn ratio were measured in 55 patients with breast disease (20 with benign breast diseases and 35 patients with breast cancer) and 30 controls. The mean serum copper levels were higher in breast cancer than in benign breast diseases (167.3 micrograms/dl vs. 117.6 micrograms/dl) (P less than 0.001) and controls (167.3 micrograms/dl vs. 98.8 micrograms/dl) (P less than 0.001). Patients with advanced breast cancer had higher serum copper levels than did patients with early breast cancer (177.9 micrograms/dl vs. 130.4 micrograms/dl) (P less than 0.001). The mean serum zinc levels were lowered only in patients with advanced breast cancer as compared with controls (88.6 micrograms/dl vs. 115.1 micrograms/dl) (P less than 0.001). Serum zinc levels were not decreased in patients with early breast cancer and benign breast diseases. The Cu/Zn ratio was increased in breast cancer patients (1.91 vs. 0.86) (P less than 0.001) but not in patients with benign breast diseases. The precise mechanisms responsible for the alterations in trace element levels in breast cancer patients are still unclear and require further evaluation. However, the serum copper levels and the Cu/Zn ratio may be used as biochemical markers in these patients.     

Electrocatalytic effects in the electrochemical reduction of pyrazine on single crystal IB metal electrodes

Due to the presence of the second nitrogen atom, pyrazine has an increased affinity for electrons and lower energies of the empty orbitals than pyridine. For this reason the electrochemical reduction of pyrazine takes place at considerably less negative potentials than that of pyridine. The reduction of pyrazine on Cu(111), Ag(111) and Au(111) electrodes in neutral aqueous media has been found to take place in one step as previously reported for Hg. The potential region and the current densities associated with this process were, however, observed to depend significantly on the electrode nature. Pyrazine was also found to be involved in a chemical interaction with the hydrogen atoms resulting in the water electro-reduction process occurring on Au(111) and Cu(111). The specific interaction of water with the single crystal electrodes turned out to be an important factor for developing the reduction of the organic molecule, both chemically and electrochemically.     

Effect of divalent cations and proteases on skin sulfhydryl oxidase activity

Crude skin sulfhydryl oxidase was independently isolated from the living cell layer, the granular cell layer, and the lower living cell layer (spinous and basal) of cow snout. The properties of this enzyme were subsequendy investigated. The addition of 1 mM CuCl₂ and FeCl₂ stimulated the enzyme activity to 216% and 166% of the initial activity, respectively. Neither CaCl₂ nor MgCl₂ had much effect on the activity, and ZnCl₂ inhibited it. Diethyldithiocarbamate (DEDTC), a copper ion chelating agent, inhibited the activity in a dose and pre-incubation time-dependent manner: however, other divalent cation chelators such as EDTA, EGTA, o-phenanthrolin and α,α'-dipyridyl did not have any effect on the enzyme's behavior. From these findings, it was determined that Cu²⁺ was essential for the activity of skin sulfhydryl oxidase. This enzyme was stimulated to 130–150% of its initial activity by treatment with 1 mg/ml trypsin, chymotrypsin or urokinase but was not affected by plasmin, elastase or cathepsin D. Trypsin treatment enhanced the activity in a dose and treatment-time dependent manner. Skin sulfhydryl oxidase from the lower living cell layer (spinous and basal) was more highly activated by trypsin treatment than was that from the granular cell layer. These findings suggest that this enzyme may be activated by some kind of serine proteases during the keratinocytes autolysis process in the granular cell layer.     

Lens superoxide dismutase and catalase activities in diabetic cataract

OBJECTIVE: Biochemical evidence suggests that the oxidative damage of the lens proteins is involved in the genesis of senile cataract and the development of diabetes-related pathologic changes such as the formation of cataracts. In particular, lens proteins are subject to extensive oxidative modification. Oxidative damage either decreases the antioxidant capacity or decreased antioxidant capacity results in oxidative damage. The purpose of this study was to analyze the activities of the antioxidant enzymes such as Cu,Zn Superoxide Dismutase (Cu,Zn-SOD) and catalase in the cataractous lenses of the type 2 diabetic group and cataractous lenses of the senile group. METHOD: Eighteen diabetic cataractous lenses and twenty six senile cataractous lenses were studied. Cu,Zn-SOD activity was measured in lenses by enzymatic method and catalase activity was measured by colorimetric method. RESULTS: Cu,Zn-SOD levels were significantly lower in the diabetic cataractous lenses than senile cataractous lenses (respectively 8.052 +/- 0.818, 18.216 +/- 4.217 microg/g prot. p < 0.05). Similarly, catalase levels were significantly lower in the diabetic cataractous lenses than senile cataractous lenses (respectively 0.326 +/- 0.134, 0.665 +/- 0.322 kU/g prot. p < 0.001). CONCLUSION: The results of the present study indicate that the antioxidant capacity in the diabetic cataractous lenses were decreased and this result suggests a role of antioxidant enzymes in the genesis of diabetic cataracts.