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41.
Luteolin alleviates bronchoconstriction and airway hyperreactivity in ovalbumin sensitized mice 总被引:7,自引:0,他引:7
OBJECTIVE AND DESIGN: Asthma is an inflammatory disease of the airways and the current focus in managing asthma is the control of inflammation. In this study, we attempted to investigate the anti-asthmatic potential of a plant derived natural compound, luteolin. MATERIAL: We used a murine model of airway hyperreactivity, which mimicked some of the characteristic features of asthma. Male BALB/c mice (8-9 weeks) were used for this study. TREATMENT: Mice (n = 6) were sensitized by intraperitoneal (i. p.) injection of 10 mg of ovalbumin (OVA) on days 0, 7 and 14 followed by aerosol inhalation (5% OVA) treatments daily beginning from day 19 to day 23. To study its preventive effect, luteolin (0.1, 1.0, and 10 mg/kg body weight; daily) was administered orally during the entire period (0 to 23 day) of sensitization. To study its curative effect, mice were first sensitized and then luteolin (1.0 mg/kg body weight daily) was given orally from day 26 to 32. The airway hyperreactivity, immunoglobulin E (IgE) in the sera, and cytokines (IFN-gamma, IL-4 and IL-5) in the bronchoalveolar lavage fluid (BALF) were measured. RESULTS: Both during sensitization and after sensitization, luteolin, at a dose of 0.1 mg/kg body weight, significantly modulated OVA-induced airway bronchoconstriction and bronchial hyperreactivity (p < 0.05). Luteolin also reduced OVA-specific IgE levels in the sera, increased interferon gamma (IFN-gamma) levels and decreased the interleukin-4 (IL-4) and interleukin-5 (IL-5) levels in the BALF. CONCLUSION: Our study showed that luteolin treatment during and after sensitization significantly attenuated the asthmatic features in experimental mice. Therefore, luteolin could be used either as a lead molecule to identify an effective antiasthma therapy or as a means to identify novel anti-asthma targets. 相似文献
42.
Angie S. Price Amy K. Nelson Alip Ghosh Shyamasundaran Kottilil Joel V. Chua 《Journal of medical virology》2023,95(1):e28105
Retrospective data showed that when we administered ledipasvir/sofosbuvir (LDV/SOF) to patients with hepatitis B and C coinfection, there was a modest reduction in hepatitis B surface antigen (HBsAg). Therefore, we hypothesize that similar HBsAg reduction can be seen in hepatitis B virus (HBV) monoinfected subjects. Primary and secondary efficacy endpoints are the decline in HBsAg and HBV DNA at Week 12 from baseline, respectively. We conducted an open-label Phase 2 pilot study to evaluate the safety, tolerability, and antiviral activity of LDV and/or SOF for HBV. Eligible subjects were either suppressed on antivirals (Group B) or inactive chronic HBV (Group A, C, D). Group A and B received LDV/SOF. Group C and D received SOF 400 mg and LDV 90 mg, respectively. All subjects completed the study, and all related adverse events (AEs) were mild. No discontinuations due to AEs or hepatitis flare occurred. At Week 12, HBsAg decline (log10 IU/ml) was similar between Group A (0.399) and B (0.400), less in Group C (0.207), and none in Group D, and there was HBV DNA decline in the inactive chronic HBV groups. LDV and SOF are safe and well tolerated when given to chronic hepatitis B subjects and have modest antiviral activity, particularly when given in combination. 相似文献
43.
beta-Tethymustine, 1-[2- {bis(2'-chloroethyl)amino}ethyl]spiro[imidazolidine-4,2'-(1'H),3',4'-dihydronaphthalene]-2,5-dione, has been synthesised and LD50 value determined in Swiss male mice, which was found to be 100.00 mg/kg by single i.p. injection. The following three criteria, namely ascites cell count, ascites fluid measurement and increase in median survival times (MST) of drug-treated (T) over untreated control (C) mice, were studied for evaluation of its antitumour efficacy in vivo in three murine ascites tumours, namely Ehrlich ascites carcinoma (EAC), sarcoma-180 (S-180) and Dalton's lymphoma (DL). At the optimum dose range of 8.0 mg/kg (higher) to 4.0 mg/kg (lower) for 1-7 days treatment following tumour transplantation on day 0, it exhibited a very high percentage of inhibition of both the ascites cell and fluid in these models and displayed excellent ILS(max) value of 80 in EAC, 224 in S-180 and 240 in DL, respectively, showing 'curative' effect (2-3/6 mice having 90 days survival rate). It also demonstrated a high ILS value of 150 with one cure/six mice bearing S-180 for 6 days prior to drug therapy. Screening results were compared with two clinical drugs, cyclophosphamide and 5-fluorouracil, serving as positive controls. Its chemical alkylating activity was compared with nor-HN2 (NSC 10873) and spiromustine (NSC 172112). The results indicate that it possesses greater alkylating activity than nor-HN2 and comparable activity with spiromustine. 相似文献
44.
Bhatavdekar J Patel D Trivedi C Dave R Nadkarni S Karelia N Vora H Ghosh M Patel S Suthar T Doctor S Balar D 《Oncology reports》1994,1(1):255-257
Hormones are believed to play a dominant role as promoters in the growth and development of hormone-dependent cancers. Much less is known about the circulating hormones in male patients with oesophageal cancer. This lack of attention led us to evaluate the role of peptide and steroid hormones (by RIA) in male patients with oesophageal cancer (n=49). Blood samples of patients were collected pretherapeutically and data was compared with age matched controls (n=25). In this retrospective study, significantly high levels of FSH (P<0.02), LH (P<0.001) and prolactin (P<0.001) were observed with concomitant low levels of estradiol (P<0.001), DHEA-S (P<0.02) and testosterone (P<0.001) in patients when compared with respective controls. The patients when grouped according to anatomical site and histological type of the tumor, intergroup variation was not observed in these hormones. From our, study, it seems that hormonal imbalance or altered ratio of peptide and steroid hormones might be playing a significant role in the development and/or progression of oesophageal carcinoma in men. 相似文献
45.
46.
Immunohistological localisation of vascular endothelial growth factor in human endometrium. 总被引:2,自引:0,他引:2
B Naresh J Sengupta V Bhargava G Kinra J Hu D Ghosh 《Indian journal of physiology and pharmacology》1999,43(2):165-170
Several polypeptide growth factors regulate epithelial and stromal development in endometrium under the influence of estrogen and progesterone, and thereby regulate growth and differentiation of endometrium during menstrual cycle. However, little is known about the angiogenic growth factors that may affect endometrial vasculature throughout each menstrual cycle. Vascular endothelial growth factor (VEGF) is suggestively an important angiogenic growth factor in the female reproductive tract. The aim of the present study was to immunolocalize and assess semi-quantitatively VEGF immunostaining in cells of proliferative phase (n = 3), secretory phase (n = 6) and hyperplastic (n = 6) human endometrial samples. VEGF concentrations were significantly higher in glandular (P < 0.001) and stromal (P < 0.01) compartments of proliferative stage endometrium compared with those in secretory stage and hyperplastic endometrial samples, with no difference in the scores for glandular and stromal compartments between secretory stage and hyperplastic endometrial samples. Generally, glandular expression of VEGF was higher as compared to stromal compartment. Thus, it appears that endometrial VEGF expression and concentration are enhanced by estrogen, and may be correlated with neovascularization and increased vascular permeability during late proliferative period. Additionally, there was no enhancement in VEGF expression in hyperplastic glands, suggesting that regulation of glandular growth and that of angiogenesis in human endometrium operate through different mechanisms. 相似文献
47.
48.
P Ghosh 《The Journal of laryngology and otology》1977,91(12):1077-1083
A new one-stage operation of constructing a 'Neo-Larynx' after total laryngectomy, transverse tracheo-oesophagoplasty, for a good alaryngeal ('Tracheo-Oesophageal') speech is described. A 'Neo-Epiglottis' is constructed from the posterior tracheal wall and a 'Pseudo-Glottis' in the tracheo-oesophagenal partition wall with a valvular mechanism for preventing aspiration into the trachea during deglutition. No extraneous tissue is used for the construction of the 'Neo-Larynx' and no practice is necessary on the part of the patient for developing alaryngeal 'Tracheo-Oesophageal' speech. The patient can phonate immediately after removal of the feeding tube and the silastic sheet and is ready for discharge five weeks after operation. Adequate surgical ablation is ensured and at the same time good functional rehabilitation is offered without jeopardizing the principles of cancer surgery, i.e. to be on the overdoing side rather than on the underdoing one in a futile attempt at retaining the function. 相似文献
49.
The synthesis and release of procoagulant activity (PCA) from leukaemic leucocytes was studied in anin vitro culture system stimulated by endotoxin. Puromycin, actinomycin-D, vinblastine, colchicine, dibutyryl cyclic AMP and ouabaln were added to the culture system to study some of the metabolic processes of these cells in relation to synthesis and release of PCA. It was found that production of PCA is an active process and depends on new protein synthesis. The release of PCA from cells can be inhibited by vinblastine, an inhibitor of microfilament and microtubules in the cell. The optimal release of PCA occurs at pH 7.2-@#@ 7.4 at 37°C and is not inhibited by the ATPase inhibitor ouabaln. Dibutyryl cyclic AMP inhibits the release/synthesis of PCA. Gram negative septicaemia and endotoxinaemia are capable of increased production and release of PCA from leukaemic cells and could contribute to the coagulation fallure seen in this disease. 相似文献
50.
P K Ghosh G Pohla-Gubo H Pohla H Antretter F Unger 《The Journal of cardiovascular surgery》1992,33(1):28-32
Serial estimation of total immunoglobulin E (IgE) concentration in 30 consecutive male patients undergoing coronary artery bypass grafting revealed three patterns--a low, middle and high response--during the perioperative period. The mean IgE level was higher in patients with higher mean preoperative left ventricular ejection fractions and these patients had a higher left ventricular stroke work index. However, there was no correlation with the severity of coronary artery disease or with degree of adequacy of revascularisation. Mean IgE level correlated moderately well with the mean right ventricular stroke work index and mean pulmonary capillary wedge pressure and minimally with the triple index. A higher level of IgE was usually observed with better cardiac performance and may be associated with factors related to the pulmonary circulation. However we could neither confirm nor refute whether an elevated level of IgE indicated an increased risk of cardiovascular events or a "protected status" against the complications of necrotising ischemia. 相似文献