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71.
The present study was designed to evaluate the in vitro cytotoxic effect of methanol extract of aerial parts including stems, leaves and twigs of Aralia cachemirica and purified continentalic acid isolated from this extract against a panel of human cancer cell lines of varied tissues. Percentage of growth inhibition was evaluated by sulphorhodamine B assay. Purified continentalic acid showed moderate cytotoxicity against all the cell lines used. In contrast, the extract exhibited significant concentration dependant cytotoxicity against A-549 (lung), THP-1 (leukemia) and MCF-7 (breast) cell lines. This work highlights cytotoxic potential of this extract, which can further be explored for different constituents for their possible use autonomously or in combined manner in cancer therapy. The detailed analysis of their cytotoxicity has been presented in this paper.  相似文献   
72.
For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. However, their poor long-term stability in different environments, namely, pH, ionic strength, and temperature, and cytotoxicity toward mammalian cells has restricted their more extensive applications. Hence, there is urgent need to develop highly biocompatible, non-toxic, and stable silver nanoparticles for wide-ranging environments and applications. In the present study, a simple, sustainable, cost-effective and green method has been developed to prepare highly stable aqueous colloidal silver nanoparticles (AgNPs-EW) using the ovalbumin, ovotransferrin, and ovomucoid of egg-white as reducing and capping agents accomplished under the irradiation of direct sunlight. Then, we evaluated the effects of freezing–drying (lyophilization) and freeze–thaw cycles on the stability of AgNPs-EW in aqueous solution under visual inspection, transmission electron microscopy, and absorbance spectroscopy. In addition, we studied the antibacterial activity against Salmonella typhimurium and Escherichia coli, carried out biocompatibility studies on chicken blood, and tested acute, chronic toxicity in Drosophila melanogaster. The results suggest that AgNPs-EW did not aggregate upon freeze-thawing and lyophilization, thus exhibiting remarkable stability. The antibacterial activity results showed that the AgNPs-EW had the highest antibacterial activity, and the minimum inhibitory concentration (MIC) of AgNPs-EW for E. Coli and S. typhimurium were 4 and 6 μg ml−1, respectively. The biocompatibility study revealed that the AgNPs-EW did not induce any hemolytic effect or structural damage to the cell membranes of chicken erythrocytes up to a concentration of 12 μg ml−1. Similarly, no acute and chronic toxicity was observed on melanization, fecundity, hatchability, viability, and the duration of development in the 1st generation of Drosophila melanogaster at the concentration range of 10 mg L−1 to 100 mg L−1 of AgNPs-EW, and all the flies completed their full developmental cycle. Therefore, the present study successfully demonstrated the green and sustainable preparation of non-toxic AgNPs-EW having good biocompatibility, enhanced colloidal stability, and antibacterial activity. Hence, the synthesized AgNPs-EW could be used for the development of an antimicrobial formulation for controlling microbial infection.

For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity.  相似文献   
73.
Metabolic Brain Disease - The night shift paradigm induces a state of chronic partial sleep deprivation (CPSD) and enhances the vulnerability to neuronal dysfunction. However, the specific neuronal...  相似文献   
74.
The effects of respiratory movements on the ultrasonic echoes of the cardiac structures were recorded and analyzed in 50 consecutive patients. Deep inspiration in cooperative patients resulted in a considerable increase of dense anterior echoes, with blotting out of any distal or posterior echoes in 12 of 44 patients (group A). In the second or larger series (32 of 44 patients; group B), a posterior displacement of most of the identifiable intrinsic cardiac echoes was seen with deep inspiration, particularly those of the posterior wall of the left ventricle. Forced expiration produced an opposite or anterior displacement of the cardiac echoes. Normal respirations showed similar but smaller excursions.  相似文献   
75.
Cross-sectional and Doppler echocardiography are currently the most important non-invasive tests for the evaluation of mitral stenosis. Recent experience has, however, shown that parameters that are reliable before mitral valvotomy may not be valid after the procedure. We have studied the validity of estimation of the area of the mitral valve by echo-planimetry, by Doppler pressure half time and the transmitral end-diastolic pressure gradient calculated by continuous wave Doppler in 100 patients (aged 10-30 years) before and after balloon mitral valvoplasty (n = 70) or surgical closed mitral valvotomy (n = 30). These patients underwent cardiac catheterisation and echocardiographic studies before, immediately after and 8-12 (9.3 +/- 2.2) weeks following balloon valvoplasty or closed valvotomy. The area as estimated echocardiographically correlated well with that obtained by the Gorlin formula before (r = 0.80), but not immediately after (r = 0.67) or on follow up after mitral valvotomy. There was good correlation between Doppler pressure half time and the area as estimated by the Gorlin formula before (r = 0.89) and on follow up after valvotomy (r = 0.82), but the correlation was not as good in the immediate period after valvotomy (r = 0.60). The end-diastolic pressure gradients obtained by Doppler examination and at cardiac catheterisation correlated well with each other before (r = 0.94), immediately after valvotomy (r = 0.92) and on follow up (r = 0.94). Hence, the reliability of estimation of the area of the mitral valve by echo-planimetry and by Doppler pressure half time varies according to the time at which the examination is performed following commissurotomy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
76.
Four uremic patients on maintenance hemodialysis developed intractable heart failure and atrioventricular block. All had persistently high (over 60) calcium-phosphorus products. At autopsy, all had metastatic myocardial calcification. Their inability to take phosphate-binding agents orally is responsible for this fatal complication.  相似文献   
77.
Clinical manifestations of aortoarteritis (Takayasu's arteritis) are varied, depending on the involved segment of the aorta and its branches. A case of a young Indian woman with aortoarteritis presenting primarily with hypoparathyroidism is reported. Aortogram showed total occlusion of the arch arteries. To the best of our knowledge, the occurrence of hypoparathyroidism in aortoarteritis has not been reported. Possible mechanisms of such an involvement are discussed.  相似文献   
78.
Pseudoaneurysm following diagnostic or interventional procedures is a well-known complication. We describe a new method of closing a femoral pseudoaneurysm in a case where ultrasound-guided compression had failed. Instead of packing the sac permanently with coils, thrombus formation was successfully induced by temporary placement of a coil transcutaneously in the psendoaneurysm sac, which resulted in closure of the pseudoaneurysm.  相似文献   
79.
BACKGROUND: Women have worse outcomes after myocardial infarction and coronary revascularization. The explanations are likely multifactorial but may include smaller coronary artery size. Smaller luminal diameter has been confirmed angiographically; however, because of possible confounding effects of coronary remodeling, angiographically silent atherosclerosis, and body size, it is unclear if there is a true sex influence on arterial size. METHODS: We performed intravascular ultrasound on left main (LM) and proximal left anterior descending (LAD) coronary artery segments that were free of significant atherosclerosis in 50 men and 25 women. Arterial and luminal areas were measured by planimetry and corrected for body surface area. We evaluated associations between sex and coronary dimensions with univariate and then multiple linear regression analyses. RESULTS: Mean uncorrected LM and LAD arterial areas were smaller in women than in men (21.53 vs 26.95 mm(2), P <.001, and 14. 68 vs 19.94 mm(2), P =.002, respectively), as were mean LM and LAD luminal areas (15.94 vs 18.79 mm(2), P =.020, and 10.13 vs 12.71 mm(2), P =.036, respectively). In multivariate models accounting for body surface area and controlling for other factors, sex independently predicted corrected LM and LAD arterial area. In analyses that additionally controlled for plaque area, sex independently predicted corrected LAD luminal area. CONCLUSIONS: LM and LAD arteries are smaller in women, independent of body size. This suggests an intrinsic sex effect on coronary dimensions. Future studies should investigate underlying mechanisms because they may lead to novel therapeutic strategies and improved outcomes for women with coronary artery disease.  相似文献   
80.
Estrogens protect healthy women from cardiovascular disease. However, epidemiological data suggest that women with diabetes are denied the cardioprotection associated with estrogens. Whether or not hormonal replacement therapy (HRT) confers cardiovascular benefits in postmenopausal women with diabetes is not known. The aim of this study was to examine the effects of HRT on the microvascular reactivity and endothelial function of individuals with and without diabetes. We studied the following groups of individuals: premenopausal healthy women [n = 28, age 41 +/- 8 yr (mean +/- SD)], premenopausal women with type 2 diabetes (n = 16, age 43 +/- 6 yr); postmenopausal healthy women (n = 12, age 57 +/- 4 yr), postmenopausal women with diabetes (n = 17, age 62 +/- 5 yr); postmenopausal healthy women on HRT (n = 13, age 51 +/- 5 yr), postmenopausal women with diabetes on HRT (n = 11, age 57 +/- 7 yr). We used laser Doppler flowmetry to measure forearm cutaneous vasodilatation in response to iontophoresis of 1% acetylcholine (endothelium dependent) and 1% sodium nitroprusside (endothelium independent). The endothelium-dependent vasodilation was significantly higher in premenopausal healthy women (180 +/- 67%; increase over baseline) compared to premenopausal diabetic women (87 +/- 41%; P < 0.001). endothelium-dependent vasodilation was also higher in postmenopausal healthy women on HRT (143 +/- 52) compared with postmenopausal diabetic women on HRT (86 +/- 61), postmenopausal healthy women without HRT (104 +/- 43), and postmenopausal diabetic women without HRT (74 +/- 28; P < 0.001). A similar pattern of responses was observed in the endothelium-independent vasodilation (premenopausal healthy women, 126 +/- 56; premenopausal diabetic women, 88 +/- 26; postmenopausal healthy women on HRT, 121 +/- 37; postmenopausal diabetic women on HRT, 88 +/- 41; postmenopausal healthy women without HRT, 84 +/- 36; and postmenopausal diabetic women without HRT, 73 +/- 36; P < 0.001). Soluble intercellular adhesion molecule (sICAM) was also measured among all the women with diabetes. Premenopausal women with diabetes (248.9 +/- 56 ng/ml) and postmenopausal women with diabetes on HRT (257.7 +/- 49 ng/ml) had lower sICAM levels compared with the postmenopausal diabetic women without HRT (346.4 +/- 149 ng/ml; P < 0.05). We conclude that menopausal status and type 2 diabetes are associated with impaired microvascular reactivity. HRT substantially improves microvascular reactivity in postmenopausal healthy women. In contrast, the effect of HRT on the microvascular reactivity of postmenopausal diabetic women is less apparent. However, the use of HRT among women with diabetes is associated with lower sICAM levels, suggesting an attenuation in endothelial activation.  相似文献   
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