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1.
The mixed bis(arylhydrazones) of l-threo-2,3-hexodiulosono-1,4-lactone rearrange into pyrazolediones. Mono- and bis-(arylhydrazones) of isoascorbic acid were prepared; the latter are present in two forms that afford the same pyrazoledione. Acetylation, benzoylation, and periodate oxidation of these pyrazolediones were studied, and some condensation products from the pyrazole aldehyde were prepared. Some of the i.r. and mass-spectral data were discussed.  相似文献   
2.
Pithecellobium dulce has been used in traditional medicine to treat various ailments owing to its restorative properties. The biological activities and chemical profiles of the lipophilic fraction of P. dulce bark and leaves were assessed herein. Fatty acid methyl esters (FAME) and unsaponifiable matter (USM) were prepared and analyzed by GC/MS. A total of 40 compounds were identified in the bark saponifiable fraction, whereas 9 compounds were annotated in the leaves. Palmitic acid methyl ester was the major compound identified accounting for 41.48 % of the bark and 19.03 % of the leaves composition. Besides, linolenic acid methyl ester (22.40 %) and linoleic acid (12.69 %) were annotated in the leaves saponifiable fraction. A total of 63 compounds were detected in the bark USM and 4 compounds were identified in the leaves. Phytol represented the major component in the leaves (52.57 %) followed by lupeol (20.68 %) and lupenone (8.60 %). Meanwhile, n‐dodecane dominated in the bark USM accounting for 24.69 % of the total composition. The leaves and bark lipophilic fractions revealed moderate antioxidant and antibacterial activities. Both extracts showed no antifungal activity. No cytotoxicity was observed for both lipophilic fractions. P. dulce offers a good source of antioxidant compounds that can be introduced to food and pharmaceutical industry.  相似文献   
3.
Column chromatography of the dichloromethane fraction from an aqueous methanolic extract of fruit peel of Citrus pyriformis Hassk. (Rutaceae) resulted in the isolation of seven compounds including one coumarin (citropten), two limonoids (limonin and deacetylnomilin), and four sterols (stigmasterol, ergosterol, sitosteryl-3-beta-D-glucoside, and sitosteryl-6'-O-acyl-3-beta-D-glucoside). From the ethyl acetate fraction naringin, hesperidin, and neohesperidin were isolated. The dichloromethane extract of the defatted seeds contained three additional compounds, nomilin, ichangin, and cholesterol. The isolated compounds were identified by MS (EI, CI, and ESI), 1H, 13C, and 2D-NMR spectral data. The limonoids were determined qualitatively by LC-ESI/MS resulting in the identification of 11 limonoid aglycones. The total methanolic extract of the peel and the petroleum ether, dichloromethane, and ethyl acetate fractions were screened for their antioxidant and anti-inflammatory activities. The ethyl acetate fraction exhibited a significant scavenging activity for DPPH free radicals (IC50 = 132.3 microg/mL). The petroleum ether fraction inhibited 5-lipoxygenase with IC50 = 30.6 microg/mL indicating potential anti-inflammatory properties. Limonin has a potent cytotoxic effect against COS7 cells [IC50 = (35.0 +/- 6.1) microM] compared with acteoside as a positive control [IC50 = (144.5 +/- 10.96) microM].  相似文献   
4.
Cellular exposure to ionising radiation leads to oxidative stress events, which refer to elevated intracellular levels of reactive oxygen species (ROS). The elevated levels of ROS significantly contributed to γ-radiation (IR) induced cytotoxicity. In an attempt to minimise these cytotoxic effects, antioxidant compounds have been identified to counteract radiation- associated toxicities. We mainly aimed to study the protective effect of 4-(4-hydroxy-3-methoxyphenyl)-2-butanone (HMB) on IR-induced nephrotoxicity, whereas it was previously shown to have anti-inflammatory effects in different inflammation models. Animals were treated orally with HMB (25?mg/kg b.wt daily) then performed by whole-body gamma-irradiation of animals with 6?Gy; a single dose applied on the 15th day and animals were sacrificed at the end of the 23rd day. It was found that IR exposure significantly induced renal oxidative injury that accompanied by inflammatory disturbance. Also, NADPH oxidase and iNOS gene expressions were significantly up-regulated, while the mitochondrial enzymes (complex I &; II) were significantly down-regulated in IR exposed animals. Additionally, Western immunoblotting analysis of signalling growth factor protein; p38 MAPK was significantly overexpressed. Interestingly, HMB treatment showed statistically significant amelioration in parameters with an improved histological structure upon the IR-induced nephrotoxicity. It can be concluded that modulation of NADPH-oxidase, iNOS and mitochondrial enzymes by HMB might be responsible for the amendment of the antioxidant status and impairment of p38 MAPK signal, thus attenuate the nephrotoxicity induced post IR exposure.  相似文献   
5.
The liver is an important organ, and hepatic ischemia–reperfusion (IR) injury is a frequent pathophysiological process that can cause significant morbidity and mortality. Thus, our study aimed to investigate the effect of targeting PI3K/p-Akt/eNOS (phosphoinositide 3-kinase/phospho-protein kinase B/endothelial nitric oxide synthase), Nrf2/HO-1 (nuclear factor-erythroid 2-related factor-2/heme oxygenase-1), and NF-κB/p53 (nuclear factor-κB/tumor protein 53) signaling pathways by using angiotensin (1–7) [ang-(1–7)] against hepatic injury induced by IR. Thirty-two male rats were included in sham group, ang-(1–7)-treated group, hepatic IR group, and hepatic IR group treated with ang-(1–7). The levels of hepatic ang-(1–7), angiotensin II (Ang II), angiotensin-converting enzyme 2 (ACE2), HO-1, malondialdehyde (MDA), PI3K, and p-Akt were assessed. The expressions of eNOS and B-cell leukemia/lymphoma-2 (BCL-2) in the liver were determined. Histological assessment and immunohistochemical expression of NF-κB, p53, and Nrf2 were carried out. The levels of reduced glutathione (GSH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) in serum were estimated. Results showed that administration of ang-(1–7) to hepatic IR rats led to significant amelioration of hepatic damage through a histological evaluation that was associated with significant upregulation of the expressions of PI3K/p-Akt/eNOS and Nrf2/HO-1 with downregulation of NF-κB/p53 signaling pathways. In conclusion, PI3K/p-Akt/eNOS and Nrf2/HO-1 signaling pathways are involved in the protective effects of ang-(1–7) against hepatic damage induced by IR. Therefore, ang-(1–7) can be used to prevent hepatic IR, which occurs in certain conditions such as liver transplantation, hemorrhagic shock, and severe infection.  相似文献   
6.
The essential oils isolated from the fresh flowers, fresh leaves, and both fresh and air‐dried stems of Eremophila maculata (Scrophulariaceae) were characterized by GC‐FID and GC/MS analyses. Sabinene was the major component in most of the oils, followed by limonene, α‐pinene, benzaldehyde, (Z)‐β‐ocimene, and spathulenol. The leaf and flower essential oils showed antibacterial and antifungal activity against five Gram‐positive and four Gram‐negative bacterial strains, multi‐resistant clinical isolates from patients, i.e., methicillin‐resistant Staphylococcus aureus (MRSA), as well as two yeasts. Minimum inhibitory concentrations (MICs) and minimum microbicidal concentrations (MMCs) were between 0.25 and 4 mg/ml.  相似文献   
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9.
Omega-3 fatty acids are gaining attention as a therapeutic agent of many diseases. Their protective effect in a variety of diseases has been demonstrated. To the best of our knowledge, this is the first study on omega-3 fatty acids related to acute cold-restraint stress (CRS) induced hepatic dysfunction in rats. Forty adult male Sprague–Dawley albino rats were used and classified into: control, omega-3 group, each rat was pretreated with omega-3 fatty acids; CRS group, rats were subjected to acute CRS for 6 hr; and CRS group pretreated with omega-3 fatty acids. Serum was obtained to determine corticosterone (CORT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and tumor necrosis factor-α (TNF-α) levels. Hepatic malondialdehyde (MDA) and total antioxidant capacity (TAC) levels were measured. Also, liver tissues were taken for histological examination and immunohistochemical assessment of the apoptotic marker, caspase-3. Results showed that pretreatment of stressed rats with omega-3 fatty acids led to significant decrease in hepatic MDA and increase in TAC levels. They reduced serum levels of CORT, ALT, AST, and TNF-α. Also, they improved liver damage and suppressed hepatic caspase-3 expression. In conclusion, pretreatment of stressed rats with omega-3 fatty acids has ameliorated stress-induced liver damage due to their antioxidant, anti-inflammatory, and antiapoptotic effects. So, they can be used to minimize stress complications on the liver.  相似文献   
10.
The 70% alcohol extract of the Egyptian Morus alba L. root bark was fractionated over cellulose CC eluted with water, 50% methanol and finally with 100% methanol to yield 3 fractions (MRBF-1, MRBF-2 and MRBF-3), respectively. In continuation of chromatographic purification of 70% alcohol extract fractions of the Egyptian M. alba L. root bark, 4 compounds namely: mulberroside A, 5,7,2'-trihydroxyflavanone-4'-O-beta-D-glucoside and albanols A and B were isolated from MRBF-2 for the first time from the Egyptian plant. Experimentally induced atherosclerosis was produced by feeding rats a diet enriched in coconut oil (25% by weight) and cholesterol (2% by weight) for 21 days. Then, hypercholesterolemic rats were orally administered (MRBF-1, MRBF-2 and MRBF-3 fractions) in a dose of 500 mg kg(-1) day(-1) for 15 successive days, in order to evaluate their expected hypocholesterolemic activity. Lipid profile parameters such as plasma total cholesterol, LDL-C, VLDL-C, LDL:HDL ratio and triglycerides, as well as plasma and liver lipid peroxides and glutathione-S-transferase enzyme levels, serum paraoxonase enzyme level, LDL oxidation, LDL aggregation and LDL retention, were measured. Plasma and liver glutathione-S-transferase enzyme levels were unaffected in all studied groups. The results revealed that the administration of (MRBF-2 and/or MRBF-3) fractions resulted in alleviation of atherosclerotic state. Administration of MRBF-3 significantly retained plasma and liver peroxides towards their normal levels, and also, produced significant increase in resistance towards major atherogenic modifications; namely LDL oxidation, LDL aggregation and LDL retention by 44%, 30%, and 33%, respectively. Thus, it can be concluded that the consumption of MRBF-2 and (MRBF-3, in some extent) fractions of M. alba L. root bark 70% alcohol extract may act as a potent hypocholesterolemic nutrient and powerful antioxidant via the inhibition of LDL atherogenic modifications and lipid peroxides formation in hypercholesterolemic rats.  相似文献   
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