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31.
Kasiappan Ravi Subbaih Rajasekaran Sorimuthu Subramanian 《Food and chemical toxicology》2005,43(9):1433-1439
Abnormalities in lipid profile are one of the most common complications in diabetes mellitus, which is found in about 40% of diabetics. In the present study, anti-hyperlipidemic efficacy of Eugenia jambolana seed kernel (EJs-kernel) was evaluated in streptozotocin (STZ)-induced diabetic rats and the efficacy was compared with standard hypoglycemic drug, glibenclamide. The effect of oral administration of ethanolic extract of EJs-kernel (100 mg/kg body weight) was examined on the levels of cholesterol, phospholipids, triglycerides and free fatty acids in the plasma, liver and kidney tissues of STZ (55 mg/kg body weight)-induced diabetic rats. The plasma lipoproteins and tissues fatty acid composition were also monitored. STZ-induced diabetic rats, showed significant increase in the levels of cholesterol, phospholipids, triglycerides and free fatty acids which were considerably restored to near normal in EJs-kernel or glibenclamide treated animals. The plasma lipoproteins (HDL, LDL, VLDL-cholesterol) and fatty acid composition were altered in STZ-induced diabetic rats and these levels were also reverted back to near normalcy by EJs-kernel or glibenclamide treatment. It may be concluded that, EJs-kernel possesses hypolipidemic effect, which may be due to the presence of flavonoids, saponins, glycosides and triterpenoids in the extract. The hypolipidemic effect mediated by EJs-kernel may also be anticipated to have biological significance and provide a scientific rationale for the use of EJs-kernel as an anti-diabetic plant. 相似文献
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33.
Michael F Flessner Jaewah Choi Kimberly Credit Ravi Deverkadra Karla Henderson 《Clinical cancer research》2005,11(8):3117-3125
PURPOSE: Despite evidence that regional chemotherapy improves the treatment of metastatic peritoneal ovarian carcinoma, monoclonal antibodies have not shown significant success in i.p. delivery. The present study was designed to address the hypothesis that convective penetration of macromolecular antineoplastic agents depends on a positive pressure difference between the i.p. therapeutic solution and the tumor. EXPERIMENTAL DESIGN: Nude rats with human ovarian xenografts implanted in the abdominal wall were used in experiments to facilitate in vivo measurement of tumor pressure and the treatment of the tumor with i.p. solutions at high pressures. Penetration of (125)I-labeled trastuzumab was measured with quantitative autoradiography. RESULTS: Tumor pressure profiles showed peak pressures of 32 mm Hg with mean pressures (+/- SD, mm Hg) in 12 SKOV3 tumors of 9.7 +/- 8.3 and in 15 OVCAR3 tumors of 12.5 +/- 7.0. I.p. therapeutic dwells at 6 to 8 mm Hg (maximum feasible pressure) showed significantly less penetration of trastuzumab than in adjacent normal muscle. To establish a driving force for convection into the tumor, various maneuvers were attempted to reduce tumor pressure, including treatment with taxanes or prostaglandin E(1), elimination of tumor circulation, and removal of the tumor capsule. Tumor decapsulation decreased the pressure to zero but did not enhance the penetration of antibody. Binding to specific trastuzumab receptors on each tumor was shown to be not a significant barrier to antibody penetration. CONCLUSIONS: The results only partially support our hypothesis and imply that the microenvironment of the tumor is in itself a major barrier to delivery of charged macromolecules. 相似文献
34.
Neeraj Mahindroo Zabeer Ahmed Asha Bhagat Kasturi Lal Bedi Ravi Kant Khajuria Vijay Kumar Kapoor Kanaya Lal Dhar 《Medicinal chemistry research》2005,14(6):347-368
The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine
pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo
functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions
in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect. 相似文献
35.
Manoj Kumar Reddy Somagutta Nishat Shama Maria Kezia Lourdes Pormento Ravi Pankajbhai Jagani Ngaba Neguemadji Ngardig Klodin Ghazarian Greta Mahmutaj Khaled El-Faramawy Ashwini Mahadevaiah Molly Sanjay Jain 《Reumatologia》2022,60(1):63
Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality. 相似文献
36.
Ravi A Mallika A Sama V Begum AS Khan RS Reddy BM 《Journal of ethnopharmacology》2011,137(3):1353-1359
Ethnopharmacological relevance
The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.Aim
To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.Methods
Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.Result
Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.Conclusion
The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata. 相似文献37.
Christopher Sie Ravi Kant Christian Peter Andreas Muschaweckh Monika Pfaller Lucy Nirschl Helena Domínguez Moreno Tereza Chadimov Gildas Lepennetier Tanja Kuhlmann Rupert
llinger Thomas Engleitner Roland Rad Thomas Korn 《The Journal of experimental medicine》2022,219(8)
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis. 相似文献
38.
Ravi Mahalingam Brittany Feia Colin Coleman Kusala Anupindi Pratush Saravanan Amalia Luthens Amalia Bustillos Arpita Das Eileen de Haro Lara Doyle-Meyers Jayme Looper Andrew N. Bubak Christy S. Niemeyer Brent Palmer Maria A. Nagel Vicki Traina-Dorge 《Viruses》2022,14(6)
Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2–127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing β-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread. 相似文献
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