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101.

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   
102.
7,7'-Dimethoxyagastisflavone (DMGF), a biflavonoid isolated from the needles of Taxus × media cv. Hicksii, was evaluated for its antiproliferative and antineoplastic effects in three human cancer cell lines. Interestingly, DMGF caused cell death via different pathways in different cancer cells. DMGF induced apoptosis, activated caspase-3 activity and changed the mitochondrial membrane potential in HT-29 human colon cancer cells. However, the apoptotic pathway is not the major pathway involved in DMGF-induced cell death in A549 human lung cancer cells and HepG2 human hepatoma cells. Treatment with 3-MA, an inhibitor of autophagy, significantly decreased DMGF-induced cell death in HepG2 and A549 cells, but did not affect DMGF-induced cell death in HT-29 cells. Following DMGF treatment, the HepG2 cells increased expression of LC3B-II, a marker used to monitor autophagy in cells. Thus, DMGF induced apoptotic cell death in HT-29 cells, triggered both apoptotic and autophagic death in A549 cells and induced autophagic cell death in HepG2 cells.  相似文献   
103.
Among the possible mechanisms which may cause wheezing or asthmatic episodes a genetically determined -adrenoceptor blockade and a hyperresponsiveness of -andrenoceptors has been postulated. Evidence to support this hypothesis stems from an increased bronchial sensitivity to -blockers, a reduced formation of cyclic AMP in response to -adrenergic stimulation and enhanced -adrenergic responses in asthmatic subjects. The recent development of techniques for measuring the specific, high-affinity binding of radiolabeled -and -adrenergic antagonists made it possible to study - and -adrenoceptors in vitro. Based upon the assumption that a change in the number and/or affinity of adrenergic receptors might be a general phenomenon, we have performed - and -receptor binding studies on lymphocytes and platelets from wheezing infants and asthmatic children as well as of infants, children, and adults not suffering from these diseases.Using 125[I]-cyanopindolol (ICYP) and 3[H]-yohimbine (HYOH) as highly specific ligands for - and -adrenoceptors, the following results were obtained: (1) Lymphocytes and platelets from control subjects and asthamatics bound similar amounts of ICYP and HYOH and thus showed no differences either in the number or the affinity of - and -adrenoceptors. Lymphocytes and platelets of wheezing and nonwheezing infants also bound the same amounts of the radioligands. (2) In asthmatic children receiving 4×2 puffs salbutamol -adrenoceptor were down-regulated and this may mimic -adrenoceptor blockade. (3) When subjects were divided into four categories according to age (0–5, 5–10, 10–20 years, adults) the number of -adrenoceptor binding sites showed an age-dependent increase. The number and affinity of -adreneceptor binding sites on platelets was neither influenced by age nor disease.It is concluded that the - and -adrenoceptors of wheezing infants and asthmatic children at least on blood cells are normal. However the -adrenoceptors show an age-dependent maturation process, which may account for an unresponsiveness to -adrenoceptor agonists in wheezing infants.Supported by a grant from the Ministerium für Wissenschaft und Forschung, NRWPresented at the 19th Workshop for Pediatric Research, University of Göttingen, March 10–11, 1983  相似文献   
104.
Background The Himalayan salt (HS) has become a popular alternative for the traditional table salt (TS) due to its health benefit claims, particularly for individuals with arterial hypertension. However, despite the increase in HS consumption, there is still a lack of clinical evidence to support a recommendation for its consumption by health professionals.Objective This cross-over study aimed to compare the impact of HS and TS intake on systolic blood pressure (SBP) and diastolic blood pressure (DBP), and urinary sodium concentration in individuals with arterial hypertension.Methods This study recruited 17 female patients with arterial hypertension who ate out no more than once a week. Participants were randomized into two groups, to receive and consume either HS or TS. Before and after each intervention, participants had their blood pressure measured and urine collected for mineral analysis. A p-value < 0.05 was considered statistically significant.Results There were no statistically significant differences before and after the HS intervention for DBP (70mmHg vs. 68.5mmHg; p=0.977), SBP (118.5 mmHg vs. 117.5 mmHg; p= 0.932) and sodium urinary concentration (151 mEq/24h vs. 159 mEq/24; p=0.875). Moreover, the between-group analysis showed no significant differences after the intervention regarding SBP (117mmHg vs 119 mmHg; p=0.908), DBP (68.5 mmHg vs. 71mmHg; p= 0,645) or sodium urinary concentration (159 mEq/24h vs. 155 mEq/24h; p=0.734).Conclusion This study suggests that there are no significant differences on the impact of HS consumption compared to TS on blood pressure and sodium urinary concentration in individuals with arterial hypertension.  相似文献   
105.
106.
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events.  相似文献   
107.
108.
目的 观察多药耐药蛋白1(muhidrug resistance 1,MDR1)、多药耐药相关蛋白(multidrug resistance-associated protein,MRP)5和MRP7在不同时期糖尿病小鼠视网膜中的表达变化.方法 通过腹腔注射链脲佐菌素诱导C57 BL/6小鼠建立糖尿病模型,伊文思蓝灌注检测血-视网膜内屏障变化.分别于糖尿病造模成功后的4周、12周和24周取小鼠视网膜,进行实时定量-PCR、免疫荧光、Western blotting等实验,检测各组小鼠视网膜中MDR1、MRP5和MRP7的表达变化.结果 伊文思蓝灌注结果显示在糖尿病12周就出现视网膜渗漏;实时定量-PCR结果发现与对照组相比,随糖尿病进展,MDR1、MRP5和MRP7在4周、12周和24周的表达均呈下降趋势(MDR1:P4周=0.028,P12周=0.003,P24周<0.001;MRP5:P4周=0.045,P12周=0.009,P24周<0.001;MRPy7:P4周=0.019,P12周<0.001,P24周 =0.001),在糖尿病不同时期其变化也呈下降趋势(均为P<0.05);免疫荧光观察到MDR1、MRP5和MRP7的荧光强度随糖尿病发展逐渐减弱;Western blotting检测可见在4周、12周、24周糖尿病小鼠视网膜中MDR1、MRP5和MRP7的表达均呈下降趋势.结论 在DR早期血-视网膜内屏障会受到破坏,视网膜中外排转运蛋白的表达也会受糖尿病的影响导致不同程度的下降.  相似文献   
109.
苯并二氢吡喃腙衍生物的合成及其初步药理活性   总被引:4,自引:0,他引:4  
为进一步筛选活性更强、副作用更小的抗绝经后骨质疏松症药物 ,在综合考察雷洛昔芬和异丙氧基异黄酮的基础上 ,设计合成一系列苯并二氢吡喃腙化合物 .化合物的结构均经波谱鉴定 ,并通过研究其对幼年小鼠子宫增重和血碱性磷酸酶活性的影响 ,初步考察化合物的药理活性 .结果表明 ,XY990 2具有较弱的雌激素受体激动作用和一定的雌激素受体拮抗作用 ,并有助于成骨细胞增殖 ,对治疗骨质疏松症是有利的 .  相似文献   
110.
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