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11.
Calligonolides A (1) and B (2), two new butanolides, and a new steroidal ester, 3, have been isolated from the whole plant of Calligonum polygonoides, together with four known compounds, tetracosan-4-olide, beta-sitosterol and its glucoside, and ursolic acid. Their structures were elucidated by spectroscopic and mass-spectrometric studies. Compounds 1-3 showed moderate inhibitory potential against lipoxygenase from soybean. 相似文献
12.
Razia Sultana Rizwan Arif Manish Rana Saiema Ahmedi Rabiya Mehandi Akrema Nikhat Manzoor Rahisuddin 《Luminescence》2022,37(3):408-421
An oxadiazole derivative 2 was prepared by condensation reaction through cyclization of semicarbazone in the presence of bromine; the structural confirmation was supported by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, Fourier transform-infrared spectroscopy, and liquid chromatography-mass spectrometry. Its sensing ability towards Ni2+ ion was examined showing a binding constant of 1.04 × 105 compared with other suitable metal cations (Ca2+, Co2+, Cr3+, Ag+, Pb2+, Fe3+, Mg2+, and K+) using ultraviolet–visible (UV–vis) and fluorescence spectroscopic studies. The minimum concentration of Ni2+ ions and limit of detection was found to be 9.4 μM. A job's plot gave the binding stoichiometry ratio of oxadiazole derivative 2 vs Ni2+ ions as 2:1. Furthermore, the intercalative binding mode of oxadiazole derivative 2 with calf thymus DNA was supported by ultraviolet–visible (UV–vis) and fluorescent light, viscosity, cyclic voltammetry, time-resolved fluorescence, and circular dichroism measurements. The molecular docking result gave the binding score for oxadiazole derivative 2 as −6.5 kcal/mol, which further confirmed the intercalative interaction. In addition, the antifungal activity of oxadiazole derivative 2 was also screened against several fungal strains (C. albicans, C. glabrata, and C. tropicalis) by broth dilution and disc diffusion methods. In antioxidant studies, the oxadiazole derivative 2 showed potential scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and H2O2 free radicals. 相似文献
13.
14.
Latha RM Lenin M Rasool M Varalakshmi P 《Prostaglandins, leukotrienes, and essential fatty acids》2001,64(2):81-85
Adjuvant induced arthritis (AIA) is accompanied by marked changes in the levels of lysosomal enzymes, glycoproteins and metabolic turnover of collagen. The role of a pentacyclic triterpene and eicosapentaenoic acid (EPA) derivative--Lupeol-EPA (50 mg/kg body weight--orally) was tested in vivo in rats. The increased activities of lysosomal enzymes and glycoproteins associated with decreased collagen in arthritic animals were significantly altered to nearly that of controls. Indomethacin (3 mg/kg body weight) was used as a reference compound. The therapeutic usefulness of Lupeol-EPA derivative in inflammatory conditions is attractive and deserves further work in this direction. 相似文献
15.
Our previous studies had reported that morin, a bioflavanoid exhibited potent anti-inflammatory effect against adjuvant-induced arthritic rats. In this current study, we investigated the anti-inflammatory mechanism of morin against monosodium urate crystal (MSU)-induced inflammation in RAW 264.7 macrophage cells, an in vitro model for acute gouty arthritis. For comparison purpose, colchicine was used as a reference drug. We have observed that morin (100–300 μM) treatment significantly suppressed the levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, MCP-1 and VEGF), inflammatory mediators (NO and PEG2), and lysosomal enzymes (acid phosphatase, β-galactosidase, N-acetyl glucosamindase and cathepsin D) in MSU-crystals stimulated macrophage cells. The mRNA expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6, and MCP-1), inflammatory enzymes (iNOS and COX-2), and NF-κBp65 was found downregulated in MSU crystal stimulated macrophage cells by morin treatment, however, the mRNA expression of hypoxanthine phospho ribosyl transferse (HPRT) was found to be increased. The flow cytometry analysis revealed that morin treatment decreased intracellular reactive oxygen species levels in MSU crystal stimulated macrophage cells. The western blot analysis clearly showed that morin mainly exerts its anti-inflammatory effects by inhibiting the MSU crystal-induced COX-2 and TNF-α protein expression through the inactivation of NF-κB signaling pathway in RAW 264.7 macrophage cells similar to that of BAY 11–7082 (IκB kinase inhibitor). Our results collectively suggest that morin can be a potential therapeutic agent for inflammatory disorders like acute gouty arthritis. 相似文献
16.
Soror SH Verma V Rao R Rasool S Koul S Qazi GN Cullum J 《Journal of industrial microbiology & biotechnology》2007,34(8):525-531
The genome sequence of Streptomyces coelicolor A3(2) contains 51 putative lipase and esterase genes mostly of unknown function. The gene estB (locus SCO 6966) was expressed as a His-tagged protein in E. coli. Esterase B was active at low temperatures exerting its maximum activity at 30°C and retaining more than 25% of its activity
at 4°C. The optimum pH was 8–8.5. The enzyme was active against short synthetic p-nitrophenylesters (C2–C10) with maximum activity towards the acetate ester (C2). The esterase was tested on 13 series of racemic esters of potential interest for the synthesis of chiral pharmaceutical
compounds. 4 of the series were substrates and a modest degree of enantioselectivity was observed (enantiomeric ratios of
1.1–1.9). 相似文献
17.
Mahmood Rasool Arif Malik Abdul Manan Khuram Aziz Amna Mahmood Saima Zaheer Naveed Shuja Mahmood Husain Qazi Mohammad Amjad Kamal Sajjad Karim 《Saudi Journal of Biological Sciences》2015,22(6):739-743
The present study was designed to explore the antioxidative status and circulating biochemical markers having a potential role in the pathogenesis of ethambutol (EMB) induced toxic optic neuropathy (TON) among diabetic and non-diabetic patients.Fifty patients under complete therapy of EMB for tuberculosis were included in the present study. Inclusion criteria for patients were to receive EMB everyday during treatment, a dose of 25 mg/kg for initial 2 months and 15 mg/kg during the rest of therapy period. We conducted color vision and visual acuity test for all patients.Fifteen out of fifty EMB induced TON patients, were found to be diabetic. Color vision and visual acuity test results were evaluated for diabetic and non-diabetic as well as twenty age matched controls. The results demonstrated a significant pattern of circulating biochemical markers between the studied groups. Data regarding hematological (RBC, p value = 0.02; Hemoglobin, p value = 0.02), hepatic (total bilirubin, p value = 0.01), renal (urea, p value = 0.03; creatinine, p value = 0.007), lipid (total cholesterol, p value = 0.01; total triglycerides, p value = 0.03) and antioxidative (superoxide dismutase, p value = 0.005; glutathione, p value = 0.02; catalase, p value = 0.02) profile showed a highly significant difference among the studied groups specially patients with diabetes. Malondialdehyde (MDA) level had gone significantly up in diabetic TON patients (p value = 0.02), in comparison to other antioxidants and vitamins (Vit). Vit-A, E, B1, B12 and Zinc seem to be playing a major role in the pathogenesis of TON, specially Vit-E and B1 surpassed all the antioxidants as having highly significant inverse relationships with MDA (MDA vs Vit-E, r = −0.676** and MDA vs Vit-B1, r = −0.724** respectively).We conclude that during the ethambutol therapy the decreased levels of Vit-E and Vit-B1 possibly play a role in the development of TON and may be used as therapeutic agents to lessen the deleterious effects of ethambutol. 相似文献
18.
Molecular cloning of enantioselective ester hydrolase from Bacillus pumilus DBRL-191 总被引:1,自引:0,他引:1
Rasool S Johri S Riyaz-ul-Hassan S Maqbool QU Verma V Koul S Taneja SC Qazi GN 《FEMS microbiology letters》2005,249(1):113-120
A gene from Bacillus pumilus expressed under its native promoter was cloned in Escherichia coli. Recombinant B. pumilus esterase (BPE) affects the kinetic resolution of racemic mixtures such as unsubstituted and substituted 1-(phenyl)ethanols (E approximately 33-103), ethyl 3-hydroxy-3-phenylpropanoate (E approximately 45-71), trans-4-fluorophenyl-3-hydroxymethyl-N-methylpiperidine (E approximately 10-13) and ethyl 2-hydroxy-4-phenylbutyrate (E approximately 7). The enzyme is composed of a 34-amino acid signal peptide and a 181-amino acid mature protein corresponding to a molecular weight of approximately 19.2kD and pI approximately 9.4. 3-D the structural model of the enzyme built by homology modelling using the atomic coordinates from the crystal structure of B. subtilis lipase (LipA) showed a compact minimal alpha/beta hydrolase fold. 相似文献
19.
BACKGROUND: Pleomorphic adenoma of the breast is a rare benign tumor. Only a few cases have been reported. The histologic features have been described well. However, the cytologic findings have been described in only a few papers. CASE: A 47-year-old female presented with a left breast mass of several months' duration. The clinical and mammographic findings were highly suspicious for malignancy. Following an aspiration biopsy diagnosis of "positive for malignancy," the mass was excised. The histologic diagnosis was pleomorphic adenoma (mixed tumor of salivary gland type) rather than carcinoma. CONCLUSION: The cytologic presentation of pleomorphic adenoma of the breast can masquerade as that of a malignant tumor, in this case colloid carcinoma. This case delineates the cytomorphologicfeatures of pleomorphic adenoma, which may mimic carcinoma. 相似文献
20.
BACKGROUND: Breast cysts are mainly benign and are reported in association with fibrocystic disease and phyllodes tumor. Rarely have cystic changes been reported to occur in malignant tumors. They are usually small but large in rare cases. Giant breast cysts are very rare, and only a few cases have been reported. CASE: A 37-year-old woman presented with a rapidly growing breast mass. Mammography showed a huge, well-circumscribed cystic mass (17 x 16 x 16 cm) suggestive of a benign lesion. Cytologic examination revealed a highly cellular tumor composed of malignant cells of various sizes and shapes in a necrotic background. The smears were diagnosed as positive for malignancy and suggested metaplastic carcinoma. Mastectomy was performed, and histologic study confirmed the cytologic diagnosis. CONCLUSION: This is the first reported case of a breast cyst of this size. Clinically the cyst was confused with a benign lesion. The fine needle aspiration aided the diagnosis and planning of treatment. 相似文献