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81.
Cisplatin (CP) is a chemotherapeutic drug used in treatment of malignancies. However, its clinical utility is limited by nephrotoxicity. The purpose of the present study was to investigate the protective role of grape seed proanthocyanidin extract (GSPE) (100 mg/kg/day) or fish oil (FO) (5 ml/kg/day) against cisplatin induced nephrotoxicity in terms of biochemical parameters, oxidative stress and DNA damage. CP nephrotoxiciy is manifested by increased levels of serum creatinine, urea and uric acid, accompanied by their decrease in urine. Na, K and Ca levels were altered in both serum and urine. In addition, cisplatin caused a decrease in renal GSH, SH-group, SOD, GST, and Na–K–ATPase levels. However the levels of MDA, H2O2 and NO were increased. Also, we assessed the renal genotoxic potential of cisplatin as manifested by an increase in the tail length of DNA, tail intensity (DNA %) and tail moment. On the other hand, administration of GSPE or FO pre-cisplatin treatment ameliorated the current changes in most of the above tested parameters, particularly oxidative stress, endogenous antioxidant defense system and DNA damage indicating their curative effect. Thus, it can be concluded that the consumption of GSPE or FO might be useful for preventing nephrotoxicity caused by cisplatin treatment.  相似文献   
82.
The aim of this study was to characterize the antioxidant activity of penicillin G (PG), ampicillin (AMP), oxacillin (OX) and dicloxacillin (DOX) through their reactivity towards reactive oxygen species (superoxide anion radical, ; hydroxyl radical, HO?; peroxyl radical, ROO?; hydrogen peroxide, H2O2; DPPH?) using various in vitro antioxidant assays with chemiluminescence (CL) and spectrophotometry as measurement techniques. In hydroxyl radical assays , PG, OX and AMP were found to inhibit the CL signal arising from the Fenton‐like reaction in a dose‐dependent manner with IC50 = 0.480 ± 0.020 mM, IC50 = 0.569 ± 0.021 mM, and IC50 = 0.630 ± 0.019 mM, respectively. The highest reactivity of PG among the tested penicillins towards the HO radical was confirmed in the deoxyribose degradation assay. In the ABAP‐derived ROO radical assay, the radical‐scavenging ability of the test penicillins was in the following order: AMP > PG > DOX > OX. The number of reduced DPPH radicals by the drugs tested was <1 being the biggest for PG. The weak antioxidant capacity of the test penicillins was confirmed in the trolox antioxidant capacity assay (0.075 ± 0.004; 0.093 ± 0.006; 0.123 ± 0.005; 0.126 ± 0.004) for OX, AMP, DOX, PG, respectively. Use of luminol as a CL probe for estimation of penicillin reactivity towards H2O2 showed that only AMP was able to quench light emission; the remaining antibiotics demonstrated a strong enhancing effect. All the examined compounds showed a weak antioxidant potential when estimated using the ferric‐ferrozine assay. This study is the first to report the evaluation of test penicillins as antioxidants under the same reaction conditions.  相似文献   
83.
Flavones exhibit a variety of beneficial effects and are well known for their medicinal importance in several diseases, including cardiovascular, neurodegenerative and cancer. The inclusion of the piperazine ring to the flavone backbone is an important strategy in drug discovery but only a few studies have synthesized piperazinyl flavone compounds to test their biological activity. While there is a major focus on the antioxidant properties of drugs in therapy of several diseases of inflammatory origin, we synthesized a series of the novel piperazinyl flavone analogues bearing the phenyl ring with different substituents. The analogues were evaluated for in vitro antioxidant activity against superoxide anion radical, hydroxyl radical, 2,2‐diphenyl‐1‐picrylhydrazyl radical, and hydrogen peroxide scavenging properties. The total antioxidant status based on the absorbance of the 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) radical cation (ABTS+?) and total antioxidant capacity using the Fe(III)‐ferrozine complex were also monitored. The results of the above studies showed that the compounds synthesized were found possessed moderate radical scavenging potential, and that their interaction with reactive oxygen species is complex and depends on their structural conformation and the type of substituent R in the piperazine ring being attached. Best antiradical activity were found for the compounds with methoxy groups on the phenyl ring of substituent R, whereas the presence of methoxy or trifluoromethyl groups in substituent R resulted in higher ABTS+? and ion Fe(III) reduction. These compounds are promising molecules to be used for their antioxidant properties and may be regarded, after improvement of the antioxidant potential, to control diseases of free radical etiology.  相似文献   
84.
Abstract

Carbon paste based biosensors for the determination of creatine and creatinine have been integrated into a sequential injection system. Applying the multi‐enzyme sequence of creatininase (CA), and/or creatinase (CI) and sarcosine oxidase (SO), hydrogen peroxide has been detected amperometrically. The linear concentration ranges are of pmol/L to nmol/L magnitude, with very low limits of detection. The proposed SIA system can be utilized reliably for the on‐line simultaneous detection of creatine and creatinine in pharmaceutical products, as well as in serum samples, with a rate of 34 samples per hour and RSD values better than 0.16% (n=10).  相似文献   
85.
Summary Comparative study of the different methods of extraction and estimation of the algal nitrogenous constituents mainly proteins of an Egyptian strain ofChlorella ellipsoidea had been carried out. This study also involves the assay of the different fractions of the soluble nitrogenous compounds.  相似文献   
86.
Abstract

Introduction: Stomach ulcer is one of the most prevalent disorders worldwide. The study was aimed to isolate and characterize the major polymethoxylated flavonoids in Citrus sinensis peels petroleum ether extract and investigate its protective and curative effect on gastric ulcer.

Material and methods: Some spectral analyses were used for identification of the isolated compounds from the petroleum ether extract of Citrus sinensis peels. One oral dose (0.5?ml/100?g b.wt.) of absolute ethanol was orally given to rats after starvation for 24?h to induce gastric ulcer. To explore the protective and curative role of the plant extract, it was orally (250?mg/kg b.wt.) given for 1 week either before or post-ulcer induction. A reference drug, ranitidine (100?mg/kg b.wt.), was also evaluated. Stomach acidity, gastric volume, lesion counts, glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA), succinate dehydrogenase (SDH), lactate dehydrogenase (LDH), acid phosphatase (AP), interlukin-10 (IL-10) and prostaglandin E2 (PGE2) were estimated. Stomach histopathological features were monitored.

Results: Nine polymethoxy flavonoids were identified from the extract. Treatment with C. sinensis peels extract recorded amelioration in all parameters.

Conclusion: Citrus sinensis petroleum ether peels extract had protective and curative effects against gastric ulcer. Therefore, the extract recorded anti-secretory, anti-ulcerative, anti-inflammatory, and antioxidant effects. Its healing action exceeded its protective role due to its richness in polymethoxylated flavonoids  相似文献   
87.
Biological Trace Element Research - The present study aims to evaluate the efficacy of selenium (Se) alone or combined with carbamazepine (CBZ) against the adverse effects induced by the...  相似文献   
88.
Summary The nature of the nitrogenous products formed in the cells and culture solutions of a nitrogen fixing strain of Nostoc commune was investigated. This organism was able to fix 5.4 mg nitrogen/100 mg dry algal cells. 13% of this cellular nitrogen was present in the soluble form. The assay of the different fractions of this soluble nitrogen was also made. Aspartic acid, glutamic acid and alanine were the only amino acids present in the free form. The extracellular nitrogen amounted to 30% of the total fixed nitrogen. The different fractions of this nitrogen were also assayed. Glutamic acid and aspartic acid were the only free amino acids in the culture solution. The importance of these two acids in the pathway of the fixation mechanism was discussed.  相似文献   
89.
Summary The mode of action of the cellulolytic enzymes of two strong cellulose decomposing fungi, Penicillium oxalicum Curie et Thom and Helminthosporium cyclops Drechsler, was studied. The culture filtrates and enzyme preparations obtained from them showed high cellulase activity and very weak cellobiase activity. The cellulolytic system of both experimental organisms seems to be multicomponent. The cellulase component showed its activity mainly extracellulary and the cellobiase component, mainly intracellulary. It seems, therefore, that during growth of both fungi on a cellulose medium, the extracellular cellulase acts hydrolytically on the cellulose substrate forming cellobiose which is further acted upon by intracellular cellobiase to form glucose. Paper chromatographic assay of the products of the enzymatic reaction sub-stantiated this conclusion.  相似文献   
90.
In spite of tremendous efforts exerted in the management of COVID-19, the absence of specific treatments and the prevalence of delayed and long-term complications termed post-COVID syndrome still urged all concerned researchers to develop a potent inhibitor of SARS-Cov-2. The hydromethanolic extracts of different parts of E. mauritanica were in vitro screened for anti-SARS-Cov-2 activity. Then, using an integrated strategy of LC/MS/MS, molecular networking and NMR, the chemical profile of the active extract was determined. To determine the optimum target for these compounds, docking experiments of the active extract's identified compounds were conducted at several viral targets. The leaves extract showed the best inhibitory effect with IC50 8.231±0.04 μg/ml. The jatrophane diterpenes were provisionally annotated as the primary metabolites of the bioactive leaves extract based on multiplex of LC/MS/MS, molecular network, and NMR. In silico studies revealed the potentiality of the compounds in the most active extract to 3CLpro, where compound 20 showed the best binding affinity. Further attention should be paid to the isolation of various jatrophane diterpenes from Euphorbia and evaluating their effects on SARS-Cov-2 and its molecular targets.  相似文献   
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