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1.
The effect of the oral administration ofVitex negundo leaf extract on the levels of enzymic and non-enzymic antioxidants were studied in the adjuvant induced arthritic (AIA) rats The levels of antioxidant enzymes such as SOD, CAT, GPx, G6PD, GSH and Vit-C were estimated in various groups of the experimental rats. It was observed that the antioxidant enzyme levels in the AIA were significantly low when compared to normal rats. A significant decrease in enzymic antioxidant—SOD, CAT, GPx, G6PD and non-enzymic antioxidant—GSH, Vit-C were observed in the liver of AIA rats compared to the normal rats. These results suggest that the leaf extract ofVitex negundo possesses antioxidant activity.  相似文献   

2.
Aqueous extract of the leaf and root ofNauclea latifolia Sm. (Rubiaceae) is used in Nigerian folk medicine for the treatment of hypertension. This work is carried out to investigate the effect ofNauclea latifolia leaf extract on lipid profile and cardiovascular activity of rats. Normal and 10% coconut oil fed rats were treated with the water-soluble fraction of the ethanol extract ofNauclea latifolia leaf for 2 weeks. Forty-eight mature male albino rats of the Wistar strain were divided into two experiments of four groups, each group having 6 animals. Experiment I animals were treated with the water-soluble fraction of the ethanol extract whilst experiment II animals were fed 10% coconut oil meal before treatment with the water-soluble fraction of the ethanol extract. A single oral dose ofNauclea latifolia was 170, 340 and 510 mg/kg body wt/day of the extracts respectively for 2 wks. There was no significant change in the lipid profile of the experimental animals as compared with the controls. There was about 40% relaxation on contracted thoracic aorta that was pre-contracted with 2 μM phenylephrine. The viability of the tissue was tested against 10 μM of acetylcholine. There was no significant (P>0.05) change in Na+ concentration in the serum. However, the K+ concentration in the serum of the experimental animals showed a significant increase. The study shows that ethanol extract ofNauclea latifolia has vasodilator action on the aorta and that lipid profiles of experimental rats were not affected. Furthermore, the increase in the K+ may be contributing to the vasodilator effect ofNauclea latifolia.  相似文献   

3.
In this study antioxidant activity of methanol extract of rhizomes ofCurculigo orchioides (MEC) was investigated using carbon tetrachloride (CCl4)-intoxicated rat liver as the experimental model. The hepatotoxic rats were administered MEC for 90 days (daily, orally at the dose of 70 mg per kg body weight). Lipid peroxidation (LPO) in CCl4-intoxicated rats was evidenced by a marked increment in the levels of thiobarbituric acid reactive substances (TBARS) and diene conjugates (CD), and also a distinct diminution in glutathione (GSH) content in the liver. In CCl4+MEC—treated rats these biochemical parameters attained an almost normal level. The decreased activity of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione reductase (GRD) in CCl4—intoxicated rats, and its retrieval towards near normalcy in CCl4+MEC—administered rats revealed the efficacy of MEC in combating oxidative stress due to hepatic damage. Elevated level of glutathione transferase(GTS) observed in hepatotoxic rats too showed signs of retuming towards normalcy in MEC co-administered animals, thus corroborating the antioxidant efficacy of MEC. The findings provide a rationale for further studies on isolation of active principles and its pharmacological evaluation.  相似文献   

4.
Prostaglandins and (PG) have been reported to be an important gastric acid suppressive factor. However, the mechanism underlying is yet to be clearly established. In vitro study with gastric microsomes in presence of both PGE2 and PGI2 shows a stimulation of gastric H+ K+-ATPase activity below 1X10−6M and 2.5X10−7M concentrations respectively. However, with further increase in concentrations of both PGE2 and PGI2, H+, K+-ATPase activity shows an inhibition but PGI2 completely obliterates the K+ stimulated part of H+, K+-ATPase activity at higher concentration. The H+-ion transport study using chambered frog gastric mucosa shows that both PGE2 and PGI2 inhibit H+-ion transport at 5X10−6 M and 10X10−6M concentrations respectively but the effect of PGI2 is reversible. These differential effects of PGE2 and PGI2 on microsomal H+, K+-ATPase and on H+ transport my be caused by the differential effects of these phospholipid mediators with the gastric mucosal cell membrane. This in vitro investigation shows the role of prostaglandin (s) as a physiological switch/regulator of gastric H+ ion transport leading to the cessation of gastric acid secretion.  相似文献   

5.
The influence of L(+)-tartrate on liver cell constituents were investigated, during experimental stone formation in rats. A significant increase in the liver glycollate oxidase activity was observed in the calculogenic group. Tartrate administration had a considerable lowering effect on the liver glycollate oxidase activity and it also lowered the urinary excretion pattern of oxalate. The rats fed with calculi producing diet also exhibited moderately enhanced LDH, (Na+, K+)—and (Ca2+)—ATPase activities. The activities of inorganic pyrophosphatase and aminotransferases were slightly reduced. Acid phosphatase activity was significantly reduced with tartrate treatment. The use of tartrate in urolithiasis as a prophylactic measure to prevent recurrence may be beneficial.  相似文献   

6.
Oxygen derived free radicals have been implicated in a number of clinical disorders including atherosclerosis (1), ischemic heart disease (IHD) (2), post ischemic reperfusion injury (3) and respiratory distress syndrome (4). These radical are generated by sequential reduction of molecular oxygen; the primary product being superoxide anion (O2 .−) which is subsequently reduced to hydrogen peroxide (H2O2), hydroxy1 radical (OH.) and singlet oxygen (1O2). However the evidence for ODFR induced cell damage in various clinical disorders is still debated and rests largely on free radical scavenging studies, through electron paramagnetic resonance spectroscopic (EPRS) studies have provided direct evidence for ODFR generation following coronary artery ligation (5). By definition, a free radical is an atom, ion or molecule with one or more unpaired electrons (the presence of unpaired electron in a free radical being represented by a superscribed bold dot-R.) and may be formed as a result of homolytic fission of a covalent bond or by electron transfer reactions, and may have cationic (NH3 +), anionic (O2 .−) or neutral (NO) characteristics. The most important in vivo source for these radical species have been found to be univalent biochemical redox reactions involving oxygen. (a) A:B→A.+B. (b) A:+B→A.+B.  相似文献   

7.
A clinical study was carried out on an antiprogestin, a synthetic steroid, 17 Hyroxy-11 β-(4-dimethyl amino-phenyl-1)—17 (Prop-1-ynyl-estra—4, 9, dien-3-one) for the termination of pregnancies in female subjects within 14 days of missed menstrual period and with positive urine pregnancy test (Gravindex Test). The compound was tested for its efficacy as an abortifacient and its acceptance by human subjects was assessed by measuring various biochemical parameters before and after introduction of the drug. The parameters measured in the subjects included, fasting blood sugar, blood urea, SGOT, SGPT, serum alkaline phosphatase, serum bilirubin, serum creatinine, serum proteins, A/G ratio and serum Na+, K+. Statistically insignificant variation was noted in all the parameters studied. This clearly shows that the drug is very well accepted by human subjects. 70% of the subjects tested in the pilot study aborted within 4 days of introduction of the drug. Overall, 90% of the subjects tested aborted as a result of introduction of the drug.  相似文献   

8.
Little is known of conditions which influence the stability of urinary enzymes upon storage in the bladder at 37°C. Using a continuous flow system simulatingin vivo conditions, we studied the influence of the pH of urine on the stability of two renal parenchymal enzymes N—Acetyl—β—D—Glucosaminidase (2—acetamido—2—deoxy—β—D—glucoside acetamidodeoxy glucohydrolase, NAG, EC 3.2.1.30) and L—Alanine aminopeptidase (Aminopeptidase N, AAP, EC 3.4.11.2). This continuous flow model that we have described can be employed to study the influence of pH on the stability of any renal enzyme excreted in urine. We also studied thein vitro effects of varying concentrations of low molecular weight regulatory metabolites such as urea, creatinine and uric acid and of some drugs excreted in urine, on the assay of these two enzymes. Urinary pH, urea content and some antibiotics seem to influence measured urinary NAG and AAP activities and we therefore express the need for caution before diagnostic interpretation of the urinary enzyme activities are made.  相似文献   

9.
Terminalia arjuna (T. arjuna) stem bark was successively extracted with petroleum ether (A), solvent ether (B), ethanol (C) and water (D). The lipid lowering activity of these four fractions A, B, C, and D was evaluatedin vivo in two models viz., triton WR-1339 induced hyperlipemia in rats as well as fructose rich high fat diet (HFD) fed diabetic- dyslipidemic hamsters. Hyperlipidemia induced by triton caused marked increase in the plasma levels of total cholesterol (Tc), triglyceride (Tg) and phospholipids (PL) in rats. After treament withT. arjuna fractions A, B, C, and D at the doses of 250 mg/kg per oral (p.o.),only the ethanolic fraction (C) exerted significant lipid lowering effect as assessed by reversal of plasma levels of Tc, Tg and PL in hyperlipidemic rats. In another experiment, feeding with HFD produced marked dyslipidemia as observed by increased levels of plasma Tc, Tg, glucose (Glu), glycerol (Gly) and free fatty acids (FFA) in hamsters. After treatment withT. arjuna fractions at the doses of 250 mg/kg p.o. only two fraction (B and C) could exert significant lowering in the plasma levels of lipids and Glu. in dyslipidemic hamsters.In vitro experimentT. arjuna fractions at tested concentrations (50–500 μg/ml) inhibited the oxidative degradation of lipids in human low density lipoprotein and rat liver microsomes induced by metal ions. These fractions when tested against generation of oxygen free radicals at the concentrations (50–500 μg/ml), counteracted the formation of superoxide anions (O−2) and hydrodyl radicals (OH) in non enzymic test systems. The efficacy ofT. arjuna fractions as antidyslipidemic and antioxidant agents was found, fraction C> fraction B> fraction A.  相似文献   

10.
Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O2) and hydroxyl radicals (OH−) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same.  相似文献   

11.
The development of metabolic acidosis during cardio-pulmonary bypass (CPB) is a well recognized but poorly explained phenomenon. It has been hypothesized that it is purely a development after the delivery of pump prime. A retrospective study was conducted at our hospital on 68 patients who underwent elective coronary artery bypass grafting (CABG). Sampling of arterial blood was performed at three time intervals: (T1) Baseline, prior to induction; (T2) 5 minutes after initiation of CPB and prior to administration of cardioplegia solution; (T3) during rewarming prior to weaning the patient off CPB. Measurements of Na+, K+, Cl−, pH, pCO2, HCO3 −, Base excess, Anion gap, Strong ion difference at each collection point were performed. Results were analyzed in a quantitative manner. On delivery of pump prime, all patients' developed metabolic acidosis. However, it is very important to distinguish the metabolic acidosis as their management varies. Anion gap has been found to be useful in managing peri-operative metabolic acidosis.  相似文献   

12.
Cytokines, viral load and opportunistic infections play an important role in HIV-disease progression. Hundred children vertically infected with HIV were enrolled to determine mRNA levels of TNF-α, IL-10, IL-4 and IFN-γ. These levels were estimated by amplifying cytokine mRNA from peripheral blood mononuclear cells. Severity of HIV was staged by the reduction in CD4 + T cells and the onset of opportunistic infections. IL-10 mRNA levels were observed to increase with the severity. Despite the rising IL-10 mRNA levels, TNF-α mRNA levels increased with severity of HIV and decrease in CD4 + T cell counts. IL-4 mRNA levels increased with the reduction in CD4 + T cell numbers. Depleting mRNA levels of IFN-γ contributed to the worsening of HIV disease. Increase in TNF-α and IL-4 levels appended to the disease severity by upregulation of the viral replication. Increased IL-10 levels and decreased IFN-γ levels predisposed the children to HIV associated opportunistic infections, which in return contributed to cytokine disarray.  相似文献   

13.
As the oxygen tension of inspired air falls with increasing altitude in normal subjects, hyperventilation ensues. This acute respiratory alkalosis, induces increased renal excretion of bicarbonate, returning the pH back to normal, giving rise to compensated respiratory alkalosis or chronic hypocapnia. It seems a contradiction that so many normal people at high altitude should permanently live as chronic acid–base patients. Blood gas analyses of 1,865 subjects at 3,510 m, reported a P aCO2 (arterial carbon dioxide tension ± SEM) = 29.4 ± 0.16 mmHg and pH = 7.40 ± 0.005. Base excess, calculated with the Van Slyke sea level equation, is −5 mM (milliMolar or mmol/l) as an average, suggesting chronic hypocapnia. THID, a new term replacing “Base Excess” is determined by titration to a pH of 7.40 at a P aCO2 of 5.33 kPa (40 mmHg) at sea level, oxygen saturated and at 37°C blood temperature. Since our new modified Van Slyke equations operate with normal values for P aCO2 at the actual altitude, a calculation of THID will always result in normal values—that is, zero.  相似文献   

14.
本研究在秦岭自然保护区群成本效益计量研究成果的基础上,对成本效益进行进一步分析及预测。运用统计软件SPSS17.0结合十余种拟合曲线,根据秦岭自然保护区群中7个国家级自然保护区的成本效益截面数据,尝试性地进行了综合效益及三大成本之间关系曲线拟合。研究结果表明：根据模型拟合优度R2大小及显著水平Sig.判断,最终得出了成本效益之间的关系式。即三个拟合函数分别是：①综合效益（Qt）与直接保护成本（Xa）的函数曲线方程为：Qt=-68.244＋870.688Xa-2493.849Xa2＋2304.879Xa3;②综合效益（Qt）与间接保护成本（Xb）的函数曲线方程为：Qt=17.844e1.986Xb;③综合效益（Qt）与机会保护成本（Xc）的函数曲线方程为：Qt=-78.157＋104.775Xc-32.953Xc2＋3.296Xc3。本研究结果可以为国家有关部门进行保护区投资做有益的帮助,同时为陕西省自然保护区保护政策的完善做理论支撑。  相似文献   

15.
A number of preparations are available in Ayurved for treatment of anemia and iron deficiency. This study was designed to evaluate efficacy of some of them. Six most commonly used Ayurvedic iron containing preparations (Navayasa Curna, Punarnavadi Mandura, Dhatri Lauha, Pradarantaka Lauha, Sarva-Juara-Hara Lauha and Vrihat Yakrdari Lauha) were given in a dose of 250 mg b.d. for 30 days to six groups of iron deficient anemic patients; each group consisting of 20 patients. A control group was given Allopathic preparation—Irex-12, (containing—ferrous fumarate, vitamin C, folic acid and vitamin B12); 1 capsule daily for 30 days for comparison. All hematological and iron parameters were determined before and after completion of treatment. The results showed that there was statistically significant rise (p<0.001) in all of them—Hb, PCV, TRBC, MCV, MCH, MCHC and plasma iron, percent saturation and plasma ferritin. Total iron binding capacity decreased significantly (p<0.001). The response of most of Ayurvedic preparations was better than Allopathic preparation and there was no side effect as observed with iron salts The Hb regeneration rate was 0.10 g/dl/day for Allopathic preparation; while it was above this value for all Ayurvedic preparations exceptPradarantaka Lauha which was least effective.Sarva-Juara-Hara Lauha was the drug of choice as Hb regeneration with it was highest 0.16 g/dl/day. Upon analysis of Ayurvedic drugs, these results were found to be consistent and correlated with iron content of the preparation.  相似文献   

16.
Plasma levels of lipids, lipoproteins and lipid peroxides and erythrocyte Na+−K+ ATPase, Mg2+ATPase and antioxidant enzymes were measured in type-2 diabetic patients. A significant decrease in Na+-K+-ATPase activity was observed in diabetic patients which was negatively correlated with blood glucose and lipid peroxides, while the Mg2+-ATPase activity was increased. In the diabetic subjects the plasma concentrations of Na+ and K+ were increased where as erythrocyte levels of Na+ were increased and K+ were decreased. Hyperlipidaemia and increased levels of lipid peroxides were observed in the diabetic subjects. There was a significant increase in erythrocyte catalase activity in diabetics which positively correlated with their lipid peroxides. There was no change in GPx activities between controls and diabetics.  相似文献   

17.
This article presents an analysis of the concept of disability in Amartya Sen’s capabilities and functionings approach in the context of Information and Communication Technologies (ICT). Following a critical review of the concept of disability—from its traditional interpretation as an essentially medical concept to its later interpretation as a socially constructed category—we will introduce the concept of functional diversity. The importance of human diversity in the capabilities and functionings approach calls for incorporating this concept into the analysis of well-being and quality of life in persons with disability—aspects in which ICT currently plays a major role. When one contemplates these technologies, it becomes clear that factors such as accessibility, design for all, and user participation in development and implementation processes are key strategies in promoting equal rights and equal opportunity for persons with disability in the different environments of the information society.  相似文献   

18.
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19.
Investigations were conducted to determine acute effects of Pb2+ and Cu2+ presented individually and collectively on zebrafish embryos. Aquatic safety testing requires a cheap, fast, and highly efficient platform for real-time evaluation of single and mixture of metal toxicity. In this study, we have developed a microfluidic system for phenotype-based evaluation of toxic effects of Pb2+ and Cu2+ using zebrafish (Danio rerio) embryos. The microfluidic chip is composed of a disc-shaped concentration gradient generator and 24 culture chambers, which can generate one blank solution, seven mixture concentrations, and eight single concentrations for each metal solution, thus enabling the assessment of zebrafish embryos. To test the accuracy of this new chip platform, we have examined the toxicity and teratogenicity of Pb2+ and Cu2+ on embryos. The individual and combined impact of Pb2+ and Cu2+ on zebrafish embryonic development was quantitatively assessed by recording a series of physiological indicators, such as spontaneous motion at 22 hours post fertilization (hpf), mortality at 24 hpf, heartbeat and body length at 96 hpf, etc. It was found that Pb2+ or Cu2+ could induce deformity and cardiovascular toxicity in zebrafish embryos and the mixture could induce more severe toxicity. This chip is a multiplexed testing apparatus that allows for the examination of toxicity and teratogenicity for substances and it also can be used as a potentially cost-effective and rapid aquatic safety assessment tool.  相似文献   

20.
Many layered superlattice materials intrinsically possess large Seebeck coefficient and low lattice thermal conductivity, but poor electrical conductivity because of the interlayer transport barrier for charges, which has become a stumbling block for achieving high thermoelectric performance. Herein, taking BiCuSeO superlattice as an example, it is demonstrated that efficient interlayer charge release can increase carrier concentration, thereby activating multiple Fermi pockets through Bi/Cu dual vacancies and Pb codoping. Experimental results reveal that the extrinsic charges, which are introduced by Pb and initially trapped in the charge-reservoir [Bi2O2]2+ sublayers, are effectively released into [Cu2Se2]2− sublayers via the channels bridged by Bi/Cu dual vacancies. This efficient interlayer charge release endows dual-vacancy- and Pb-codoped BiCuSeO with increased carrier concentration and electrical conductivity. Moreover, with increasing carrier concentration, the Fermi level is pushed down, activating multiple converged valence bands, which helps to maintain a relatively high Seebeck coefficient and yield an enhanced power factor. As a result, a high ZT value of ∼1.4 is achieved at 823 K in codoped Bi0.90Pb0.06Cu0.96SeO, which is superior to that of pristine BiCuSeO and solely doped samples. The present findings provide prospective insights into the exploration of high-performance thermoelectric materials and the underlying transport physics.  相似文献   

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