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201.
Oxidative stress had a great importance in development of complications in diabetes. We investigated effects of melatonin and pentoxifylline in diabetic mice. Swiss albino mice (n = 40) were divided into four groups: alloxan‐induced diabetes mellitus (DM), alloxan‐induced diabetes with melatonin supplementation (DM + MLT), alloxan‐induced diabetes with pentoxifylline supplementation (DM + PTX), and control. Glutathione‐peroxidase (GSH‐Px) activity, malondialdehyde (MDA) and reduced glutathione (GSH) levels, and susceptibility to oxidation of erythrocytes were measured. MDA levels were higher than control in the DM and DM + MLT. The DM had more MDA level than the DM + MLT and DM + PTX (P < 0.001). After in vitro oxidation, MDA levels of all groups were found higher than the control. However, they were significantly lower than the DM in DM + PTX and DM + MLT (P < 0.001). Although GSH levels of the DM and DM + PTX were less than the control, GSH‐Px activity of the DM was lower than the control and DM + PTX (P < 0.05). We suggest that there is increased oxidative stress and compromised antioxidant status of erythrocytes in diabetes; however, it can be effectively prevented by melatonin or pentoxifylline supplementation.  相似文献   
202.
Four multicaulin and miltirone-like phenanthrene derivatives were synthesised and evaluated as antituberculosis agents. The crucial step of the synthesis was Pschorr coupling of 4-(3-isopropyl-4-methoxyphenyl)-2-(2-aminophenyl)ethane (13) to give 2-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9) and 4-isopropyl-3-methoxy-9,10-dihydrophenanthrene (9a). Compound 9 was converted to multicaulin and miltirone-like phenanthrene derivatives by further reactions. The best antituberculosis activity was exhibited by 2-isopropylphenanthrene-3-ol (11).  相似文献   
203.
Acinetobacter baumannii is an important nosocomial pathogen, especially in immunocomprimised patients and those hospitalized in intensive care units. After the first isolation of A. baumannii strains from the bronchial aspirates of two patients in the intensive care unit (ICU) of our hospital as a pure culture, screening studies were performed to define possible source(s). A. baumannii strains isolated from bronchial aspirates and blood cultures of the patients in ICU were collected as a possible part of the outbreak. A total of 23 screening samples collected from equipment (7), hands (4) and gloves (2) of the staff, and from ten different body regions of the patients in the ICU were cultured. Antimicrobial susceptibility test of the isolates was performed by the standardized disk-diffusion method. All isolates were subtyped by antibiogram, arbitrarily primed polymerase chain reaction (AP-PCR) and pulsed-field gel electrophoresis (PFGE) typing methods. A total of 26 A. baumannii strains including eight clinical and 18 screening isolates were identified. All isolates were susceptible only to meropenem, tobramycin, and imipenem. There was at least a 96% resistance rate to the other antibiotics tested. Antibiogram typing showed that 24 of the 26 isolates were epidemiologically related, two were unique. AP-PCR yielded two types, one of which had 21 isolates, the other had five. PFGE fingerprinting revealed that all isolates were clonally related, including four closely related and 22 indistinguishable strains. Based on the results of PFGE which has been accepted as a reference method it can be concluded that A. baumannii strains isolated from our intensive care unit originated from a single type of strain.  相似文献   
204.
The aim of the present study was to examine serum cytokines and nitric oxide (NO) levels in patients with cystic echinococcosis (CE). 28 patients with CE were studied and all underwent surgery. Serum levels of tumour necrosis factor-alpha (TNF-alpha), interleukin IL-1beta, receptor of soluble IL-2R (sIL-2R), IL-6, IL-8, nitrate/nitrite, and C-reactive protein (CRP) were determined before and after induction of treatment. Data were compared with those obtained from 28 healthy volunteers. IL-6 was elevated in all CE patients (100%). IL-8 was increased in 11/28 (39.3%). Increased levels of IL-2R and TNF-alpha were found in a limited number of them particularly those showing cysts in the central area of the liver (5/28, 6/28). IL-1beta level was not elevated in any patient except in secondary severe CE. CRP and nitrate/nitrite levels were also increased. A positive correlation between CRP and IL-6 (r = 0.74; p < 0.001) was found confirming the link between inflammation due to CE and activation of monocytes. All patients completely recovered and the levels of the studied parameters reverted to normal levels except one patient in whom severe recurrent disease occurred two years after the first operation. These results suggest that there are different immunoregulatory events and cytokines response during CE and may be in part related to slight monocytosis and in part to Th2 activation. IL-6, NO and CRP were unambiguously involved in the host parasite interaction and therefore may be useful markers in monitoring CE management and evaluating surgical stress.  相似文献   
205.
Lithium carbonate used in the long-term treatment of manic-depressive illness has been reported to lead to progressive renal impairment in rats and humans. Caffeic acid phenethyl ester (CAPE), a component of honeybee propolis, protects tissues from reactive oxygene species mediated oxidative stress in ischemia-reperfusion and toxic injuries. The beneficial effect CAPE on lithium-induced nephrotoxicity has not been reported yet. The purpose of this study was to examine a possible renoprotective effect of CAPE against lithium-induced nephrotoxicity in a rat model. Twenty-two adult male rats were randomly divided into three experimental groups, as follows: control group, lithium-treated group (Li), and lithium plus CAPE-treated group (Li+CAPE). Li were treated intraperitoneally (i.p.) with 25 mg/kg Li2CO3 solution in 0.9% NaCl twice daily for 4 weeks. CAPE was co-administered i.p. with a dose of 10 μM/kg/day for 4 weeks. Serum Li, blood urea nitrogen and plasma creatinine, urinary N-acetyl-β-D-glucosaminidase (NAG, a marker of renal tubular injury), and malondialdehyde (MDA, an index of lipid peroxidation), were used as markers of oxidative stress-induced renal impairment in Li-treated rats. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities were studied to evaluate the changes of antioxidant status in renal tissue. Serum Li levels were found high in the Li and Li+CAPE groups. In Li-administrated rats, urinary NAG and renal MDA levels were increased according to control and Li+CAPE groups (p < 0.05). CAPE caused a significant reduction in the levels of these parameters. Likewise, renal SOD, CAT and GSH-Px activities were decreased in Li-administrated animals; CAPE caused a significant increase in the activities of these antioxidant enzymes. In conclusion, CAPE treatment has a protective effect against Li-induced renal tubular damage and oxidative stress in a rat model.  相似文献   
206.
Twenty bis-5-methylbenzimidazole compounds were evaluated for their in vitro antifungal activity against Candida albicans and Candida tropicalis. Except for three all compounds exhibited an antifungal activity against these yeasts over a range of the minimum inhibitory concentration (MIC) between 25 and 800 mg/L.  相似文献   
207.
Diabetes Mellitus (DM), a state of chronic hyperglycaemia, is a common disease affecting over 124 million individuals worldwide. In this study, erythrocyte glutathione levels, lipid peroxidation, superoxide dismutase, catalase, and glutathione peroxidase and some extracellular antioxidant protein levels of patients with type II diabetes mellitus and healthy controls were investigated. Thirty-eight patients (21 males; with age of mean +/- SD, 53.1+/-9.7 years) and 18 clinically healthy subjects (10 males; with age of mean +/- SD, 49.3+/-15.2 years) were included in the study. Levels of erythrocyte lipid peroxidation, serum ceruloplasmin and glucose levels, HbA1C levels, and erythrocyte catalase activity were significantly increased, whereas serum albumin and transferrin levels, erythrocyte glutathione levels, and glutathione peroxidase activity were significantly decreased compared to those of controls. There was no significant difference in superoxide dismutase activity compared to controls. The results suggest that the antioxidant deficiency and excessive peroxide-mediated damage may appear in non-insulin dependent diabetes mellitus.  相似文献   
208.
The effect of cigarette smoke on lipid peroxidation and antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase and on the concentration of N-methyl-d-aspartate receptor (NMDAR) subunits 2A and 2B in the hippocampus of Sprague-Dawley rats exposed to cigarette smoke for 2h/day for a period of 4 weeks was determined. It was observed that NMDAR 2A and 2B concentrations in the hippocampus were enhanced in the case of animals exposed to cigarette smoke, whereas lipid peroxidation and antioxidant enzyme activities did not show any change as compared to control animals. The results of our study suggest that cigarette smoke induces NMDAR 2A and 2B expression in the hippocampus, and that this is not due to an increased lipid peroxidation, because cigarette smoke has no effect on lipid peroxidation and antioxidant enzyme activities in the hippocampus.  相似文献   
209.
Multicenter overlap integrals appearing in the evaluation of multicenter–multielectron integrals of central and noncentral interaction potentials are calculated using complete orthonormal sets of -ETOs (=1, 0, –1, –2, ...). The final results are expressed in terms of two-center overlap integrals between STOs. The convergence of the series is tested by calculating concrete cases for arbitrary quantum numbers, screening constants and location of STOs.  相似文献   
210.
Alloiococcus otitidis has been recovered from the middle ear of children with otitis media with effusion, but its natural habitat is not known. To determine whether the nasopharynx and the outer ear canals are the natural habitats of A. otitidis, 145 swabs (50, nasopharynx; 95 outer ear canal) collected from 50 children were screened by polymerase chain reaction. A. otitidis DNA was detected in seven (4.8%) of the 145 specimens, of which four were nasopharynx, and three outer ear canal. These results indicate that the nasopharynx and outer ear canal may be the body sites for localization of A. otitidis.  相似文献   
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