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51.
Background & ObjectivesCigarette smoke is associated with several diseased states including defects in reproductive behavior. Salvadora persica (S. persica) known as the toothbrush plant is reported to possess several pharmacological properties including antidepressants and anxiolytics. The present research was done to determine the libido-protective effect of S. persica in chronic cigarette smoke-exposed rats.Materials and MethodsThe decoction of freshly dried roots of S. persica (50, 100, and 200 mg/kg, oral) was administered to the chronic-cigarette smoke-exposed adult rats. The parameters related to libido were recorded using a close-camera circuit (CCTV). Serum corticosterone and testosterone levels were estimated. Further, the phytochemical constituents were identified in the decoction. The data obtained were analyzed using one-way analysis of variance and significance was considered at p < 0.05.ResultsThe observation from the study revealed that cigarette smoke exposure reduces the sexual activity parameters significantly (p < 0.01), besides elevated the serum corticosterone and suppressed the testosterone levels in rats. Administration of S. persica at 200 mg/kg improved significantly (p < 0.05) the parameters related to libido. The decoction also reversed the changes in the levels of tested hormones in serum.Interpretation and ConclusionThe findings indicate that a 200 mg/kg S. persica decoction can protect libido in chronic cigarette smoke-exposed rats. The activity may be due to the presence of several phytoconstituents such as alkaloid, flavonoids and phytosterols that might produce vasodilatory effect in sex organs and enhance the synthesis of endogenous testosterone to improve libido characteristics weakened by chronic cigarette smoke exposure.  相似文献   
52.
In order to facilitate the discovery of novel actinomycetes from the Egyptian deserts, which can be useful as new sources for bioactive metabolites, different media for enumeration and isolation of desert actinomycetes have been tested. For this purpose, 30 soil samples from different six sites representing the Western and Eastern deserts of Egypt were collected. The two deserts are considered hyper-arid and the soil characteristics were determined. The media used were glucose–yeast extract agar, soil extract agar and a new minimal medium (MM) containing glucose, yeast extract and mineral salts. The effects of the soil characteristics on the total viable actinomycete counts on the three media were evaluated. The results showed that the highest actinomycete count in samples from five out of six sites was obtained on MM. Also MM was more selective for actinomycetes and significantly decreased the number of fungal colonies and to a lower extent the number of bacterial colonies. Moreover, it supported the development of different and diverse groups of actinomycetes. From the results obtained in this study, MM is a new useful medium for enumeration and selective isolation of actinomycetes from the desert soils.  相似文献   
53.
Investigation of the aqueous alcoholic extract of Pyruscalleryana Decne. leaves led to the isolation of two new phenolic acids glycosides, namely protocatechuoylcalleryanin-3-O-β-glucopyranoside (1) and 3′-hydroxybenzyl-4-hydroxybenzoate-4′-O-β-glucopyranoside (2), together with nine known compounds among them lanceoloside A and methylgallate, which have been isolated for the first time from the genus Pyrus. Structures of the isolated compounds were established by spectroscopic analysis, including UV, IR, HRESI-MS, and 1D/2D NMR. The total extract and some isolated compounds were determined against DPPH (2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazinyl radical, for their free radical scavenging activity, the total alcoholic extract showed strong antioxidant activity while the two new compounds showed weak antioxidant activity.  相似文献   
54.
Russian Journal of Bioorganic Chemistry - Here we synthesized novel 1, 2-diazet and pyrrole derivatives and screened for their anti-inflammatory activity. In vivo anti-inflammatory evaluation...  相似文献   
55.
The Middle East Respiratory Syndrome Coronavirus is well known to cause respiratory syndrome and this virus was identified and isolated for the first time from Jeddah, Saudi Arabia in 2012 from infected patient. In this report, we have conducted the in-silico prediction, designing and evaluation of siRNAs targeting Middle East Respiratory Syndrome Coronavirus orf1ab gene to inhibit the virus replication. By using bioinformatics software, total twenty-one functional, off-target reduced siRNA were selected from four hundred and sixty-two siRNAs based on their greater potency and specificity. We have evaluated only seven siRNAs to analyze their performance and efficacy as antivirals by reverse transfection approach in Vero cells. There was no cytotoxicity of siRNAs at various concentrations was observed in Vero cells. Based on the real-time PCR results, better inhibition of viral replication was observed in the siRNA-1 and 4 as compared to other siRNAs. The results generated from this work provided suitable information about the efficacy of siRNAs which encouraged us to further evaluate the remaining siRNAs to determine their inhibitory effect on the virus replication. We concluded that the insilico prediction and designing resulted in the screening of potential siRNAs with better efficiency, and strength. This can be used to develop oligonucleotide-based antiviral therapeutics against MERS-CoV in the near future.  相似文献   
56.
The current study used RP-HPLC to compare phytochemicals and estimate the bioactive constituents found in Stevia rebaudiana Bert. (SRB) leaves collected from two different geographical sources. SRB leaves were collected from Bangalore, Karnataka, India, and Reduit, Mauritius. Extracts were prepared using ethanol and aqueous solvents. Proximate analysis was used to evaluate moisture content, ash values, crude fibers, and extractive values. Following that, preliminary phytochemical screening was done on both ethanol leaves extracts, and subsequently total flavonoid content was determined. In addition, TLC chromatograms and RP-HPLC studies were performed on both plant extracts to determine the presence of flavonoid components in both leaves extracts, followed by in vitro anti-diabetic activity was performed with alpha amylase and alpha glucosidase enzymes against Acarbose as standard. Results revealed that both the extracts from two different geographical sources varied significantly with the yield, content of chemicals, and presence of quercetin (flavonoid) content when estimated through the RP-HPLC standardized method. Glycosides, flavonoids, proteins, steroids, saponins, terpenoids, and phenols were found in various concentrations during phytochemical screening. Among both zones, the ethanol leaves extract of SRB taken from Mauritius had a greater content of phytochemicals and a higher yield than other extracts due to the soil nature. The Mauritius sample had greater total flavonoid levels as well as more quercetin (0.92 ± 0.011) than the other extracts. Following that, ethanol extract inhibited enzymes (alpha amylase, alpha glucosidases) more than aqueous extract, and this inhibition was dose dependent. Among them, the Mauritius ethanol sample showed higher anti-diabetic efficacy than the Indian sample, but this difference was not significant. Overall, SRB ethanol leaves extracts outperformed other leaves extracts in terms of yield, phytoconstituents, and total flavonoids. Overall, both SRB samples had high quercetin levels and possessed anti-diabetic potential, but they were greater in the Mauritius sample, demonstrating that plant traits are influenced by geographic location.  相似文献   
57.
Hyaluronidase “venom spreading factor” is a common component of snake venoms and indirectly potentiates venom toxicity. It may cause permanent local tissue destruction at the bite site/systemic collapse of the envenomated victim. The present study was performed to assess the benefits of inhibiting the hyaluronidase activity of Egyptian horned viper, Cerastes cerastes (Cc). The aqueous extracts of some medicinal plants were screened for their inhibitory effect on hyaluronidase activity of Cc venom. The results revealed that the Rosmarinus officinalis (Ro) extract is the most potent hyaluronidase inhibitor among the tested extracts. The Ro extract is more potent inhibitory effect on the hyaluronidase activity than the prepared rabbit monoclonal antiserum of previously purified hyaluronidase enzyme from Cc venom (anti-CcHaseII). In addition, the Ro extract is efficiently inhibited the activity of hemorrhagic toxin previously purified from Cc venom, and it also neutralized the edema inducing activity of the Cc venom in vivo. Furthermore, the Ro extract markedly increased the survival time of experimental mice injected with lethal dose of Cc venom up to 7 h in compared to mice injected with venom alone or with venom/anti-CcHaseII (15 ± 5, 75 ± 4 min), respectively. Our findings imply the significance of plant-derived hyaluronidase inhibitor in the neutralization of local effects of Cc venom and retardation of death time. Therefore, it may use as a therapeutic value in complementary snakebite therapy.  相似文献   
58.
Glucose 6-phosphate dehydrogenase (EC 1.1.1.49) was purified from Aspergillus aculeatus, a filamentous fungus previously isolated from infected tongue of a patient. The enzyme, apparently homogeneous, had a specific activity of 220 units mg(-1), a molecular weight of 105,000 +/- 5,000 Dal by gel filtration and subunit size of 52,000 +/- 1,100 Dal by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The substrate specificity was extremely strict, with glucose 6-phosphate (G6P) being oxidized by nicotinamide adenine dinucleotide phosphate (NADP) only. At assay pH of 7.5, the enzyme had K(m) values of 6 microM and 75 microM for NADP and G6P respectively. The k(cat) was 83 s(-1). Steady-state kinetics at pH 7.5 produced converging linear Lineweaver-Burk plots as expected for ternary-complex mechanism. The patterns of product and dead-end inhibition suggested that the enzyme can bind NADP and G6P separately to form a binary complex, indicating a random-order mechanism. The enzyme was irreversibly inactivated by heat in a linear fashion, with G6P providing a degree of protection. Phosphoenolpyruvate (PEP), adenosinetriphosphate (ATP), and fructose 6-phosphate (F6P), in decreasing order, are effective inhibitors. Zinc and Cobalt ions were effective inhibitors although cobalt ion was more potent; the two divalent metals were competitive inhibitors with respect to G6P, with Ki values of 6.6 microM and 4.7 microM respectively. It is proposed that inhibition by divalent metal ions, at low NADPH /NADP ratio, is another means of controlling pentosephosphate pathway.  相似文献   
59.
Being the primary sulfonamide among the most efficient zinc binding group (ZBG) to design inhibitors for the metallo-enzymes carbonic anhydrases (CA, EC 4.2.1.1), herein, we propose an investigation on four physiologically important human (h) CAs (hCA I, II, IV, and IX) with N1-substituted secondary sulfonamides incorporating thiazolinone or imidazolone-indole tails. The effect of the functionalisation of the sulfonamide group with five different substitution patterns, namely acetyl, pyridine, thiazole, pyrimidine, and carbamimidoyl, was evaluated in relation to the inhibition profile of the corresponding primary sulfonamide analogues. With most of these latter being nanomolar inhibitors of all four considered isoforms, a totally counterproductive effect on the inhibition potency can be ascribed to N1-functionalisations of the ZBG primary sulfonamide structure with pyridine, thiazole, and pyrimidine moieties. On the other hand, incorporation of less hindered groups, such as sulfonylacetamides and sulfonylguanidines, maintained a certain degree of activity dependent on the tailing moiety, with KIs spanning in the low micromolar range.  相似文献   
60.
Origins of Life and Evolution of Biospheres - The early Solar System comprised a broad area of abiotically created organic compounds, including interstellar organics which were integrated into...  相似文献   
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