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排序方式: 共有376条查询结果,搜索用时 15 毫秒
41.
Timmers L Lim SK Hoefer IE Arslan F Lai RC van Oorschot AA Goumans MJ Strijder C Sze SK Choo A Piek JJ Doevendans PA Pasterkamp G de Kleijn DP 《Stem cell research》2011,6(3):206-214
Recent studies suggest that the therapeutic effects of stem cell transplantation following myocardial infarction (MI) are mediated by paracrine factors. One of the main goals in the treatment of ischemic heart disease is to stimulate vascular repair mechanisms. Here, we sought to explore the therapeutic angiogenic potential of mesenchymal stem cell (MSC) secretions. Human MSC secretions were collected as conditioned medium (MSC-CM) using a clinically compliant protocol. Based on proteomic and pathway analysis of MSC-CM, an in vitro assay of HUVEC spheroids was performed identifying the angiogenic properties of MSC-CM. Subsequently, pigs were subjected to surgical left circumflex coronary artery ligation and randomized to intravenous MSC-CM treatment or non-CM (NCM) treatment for 7 days. Three weeks after MI, myocardial capillary density was higher in pigs treated with MSC-CM (645 ± 114 vs 981 ± 55 capillaries/mm(2); P = 0.021), which was accompanied by reduced myocardial infarct size and preserved systolic and diastolic performance. Intravenous MSC-CM treatment after myocardial infarction increases capillary density and preserves cardiac function, probably by increasing myocardial perfusion. 相似文献
42.
Oktem F 《Plastic and reconstructive surgery》2005,115(4):1218-1219
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The objective of this study was to develop a nontoxic and noncontraceptive vaginal drug delivery vehicle for lipophilic anti-human
immunodeficiency virus (HIV) microbicides. Three representative poorly water-soluble novel broad-spectrum anti-HIV microbicides,
PHI-113, PHI-346, and PHI-443, were evaluated in 11 different solvent systems. Based on their solubility profiles, a novel
non-spermicidal self-emulsifying gel (viz Conceival) composed of pharmaceutical excipients, sorbitol, polyethylene glycol
400, polysorbate 80, microcrystalline cellulose, xanthan gum, and water was optimized. Conceival enhanced the solubility of
these poorly water-soluble (<0.001 mg/mL) anti-HIV drugs by at least 150- to 270-fold. Conceival was evaluated in vivo in
the New Zealand white rabbit model for the preservation of sperm function based on pregnancy outcome and the potential for
vaginal irritation following single and multiple intravaginal applications, respectively. Conceival administered intravaginally
immediately prior to artificial insemination with semen had no adverse effects on subsequent reproductive performance, neonatal
survival, or pup development when compared with untreated control group. Histologic evaluation of vaginal tissues of rabbits
exposed intravaginally to Conceival for 14 consecutive days revealed lack of epithelial, submucosal, and vascular changes
at the gel application site (total irritation score <3 out of a possible 16). These findings indicate that Conceival has potential
to become a clinically useful, safe noncontraceptive vaginal vehicle for lipophilic microbicides.
Published: September 20, 2005 相似文献
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Objective: The aim of this study was to investigate effect of loss weight on P wave dispersion in obese subjects. Research Methods and Procedures: After a 12‐week weight loss program (diet and medical therapy), a total of 30 (24 women and six men) obese subjects who had lost at least 10% of their original weight were included in the present study. All subjects underwent a routine standard 12‐lead surface electrocardiogram. Electrocardiograms were transferred to a personal computer by a scanner and then magnified 400 times by Adobe Photoshop software (Adobe Systems, Mountain View, CA). P wave dispersion, which is also defined as the difference between the maximum P wave duration and the minimum P wave duration, was also calculated. Results: After a 12‐week weight loss program, BMI (p < 0.001), maximum P wave duration (p < 0.001), and P wave dispersion (p < 0.001) significantly decreased. The mean percentage of weight loss was 13% (10% to 20.3%). The decrease in the level of P wave dispersion (21 ± 10 and 7 ± 12 ms, p < 0.002) was more prominent in Group II (≥12% loss of their original weight) than Group I (<12% loss of their original weight) after the weight loss program. A statistically significant correlation between decrease in the level of P wave dispersion and percentage of weight loss was found (r = 0.624, p < 0.001). Discussion: Substantial weight loss in obese subjects is associated with a decrease of P wave duration and dispersion. Therefore, these observations suggest that substantial weight loss is associated with improvement in atrial repolarization abnormalities in obese subjects. 相似文献
47.
The effect of cysteine and glutathione on sperm and oxidative stress parameters of post-thawed bull semen 总被引:2,自引:0,他引:2
Tuncer PB Bucak MN Büyükleblebici S Sarıözkan S Yeni D Eken A Akalın PP Kinet H Avdatek F Fidan AF Gündoğan M 《Cryobiology》2010,61(3):303-307
The aim of this study was to determine the effects of antioxidants such as reduced glutathione (GSH) and cysteine in Laiciphose® extender on semen parameters, fertilizing ability, lipid peroxidation (LPO) level and glutathione peroxidise (GPx) activity of post-thawed bull semen. Totally 54 ejaculates of three bulls were used in the study. Five groups, namely; GSH (0.5 and 2 mM), cysteine (5 and 10 mM) and control group, were conducted to test the antioxidants in Laiciphose®. Insemination doses were processed that each 0.25-mL straw contained 15 × 106 sperm. The addition of antioxidants did not present any significant effect on the percentages of post-thaw sperm morphology (acrosome and total abnormalities), subjective, CASA and progressive motilities, as well as sperm motility characteristics (VAP, VSL, VCL, LIN and ALH), compared to the control groups (P > 0.05). GSH 0.5 mM (55.5 ± 7.38%) and cysteine 10 mM (48 ± 5.65%) led to lower rates of DNA damage, compared to control (P < 0.05). As regards to MDA level, cysteine at 10 mM dose gave the highest level (4.99 ± 0.44 nmol/L) (P < 0.001). GPx activity was demonstrated to be higher level upon the addition of 5 mM cysteine when compared to the other groups (P < 0.05). With respect to fertility results based on 60-day non-returns, the supplementation of antioxidants did not present significant differences (P > 0.05). The results of this study may provide an useful information for the future studies in this area. So, further studies could be suggested to achieve better information in terms of the DNA damage and fertilizing capacity of bull sperm frozen with effective antioxidants. 相似文献
48.
Autophagy occurs upstream or parallel to the apoptosome during histolytic cell death 总被引:1,自引:0,他引:1
Akdemir F Farkas R Chen P Juhasz G Medved'ová L Sass M Wang L Wang X Chittaranjan S Gorski SM Rodriguez A Abrams JM 《Development (Cambridge, England)》2006,133(8):1457-1465
Histolysis refers to a widespread disintegration of tissues that is morphologically distinct from apoptosis and often associated with the stimulation of autophagy. Here, we establish that a component of the apoptosome, and pivotal regulator of apoptosis, is also required for histolytic cell death. Using in vivo and ex vivo assays, we demonstrate a global apoptogenic requirement for dark, the fly ortholog of Apaf1, and show that a required focus of dark(-) organismal lethality maps to the central nervous system. We further demonstrate that the Dark protein itself is a caspase substrate and find that alterations of this cleavage site produced the first hypermorphic point mutation within the Apaf1/Ced-4 gene family. In a model of ;autophagic cell death', dark was essential for histolysis but dispensable for characteristic features of the autophagic program, indicating that the induction of autophagy occurs upstream or parallel to histolytic cell death. These results demonstrate that stimulation of autophagy per se is not a ;killing event' and, at the same time, establish that common effector pathways, regulated by the apoptosome, can underlie morphologically distinct forms of programmed cell death. 相似文献
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Gul M Demircan B Taysi S Oztasan N Gumustekin K Siktar E Polat MF Akar S Akcay F Dane S 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2006,143(2):239-245
We investigated whether 8-week treadmill training strengthens antioxidant enzymes and decreases lipid peroxidation in rat heart. The effects of acute exhaustive exercise were also investigated. Male rats (Rattus norvegicus, Sprague-Dawley strain) were divided into trained and untrained groups. Both groups were further divided equally into two groups where the rats were studied at rest and immediately after exhaustive exercise. Endurance training consisted of treadmill running 1.5 h day(-1), 5 days week(-1) for 8 weeks. For acute exhaustive exercise, graded treadmill running was conducted. Malondialdehyde level in heart tissue was not affected by acute exhaustive exercise in untrained and trained rats. The activities of glutathione peroxidase and glutathione reductase enzymes decreased by both acute exercise and training. Glutathione S-transferase and catalase activities were not affected. Total and non-enzymatic superoxide scavenger activities were not affected either. Superoxide dismutase activity decreased by acute exercise in untrained rats; however, this decrease was not observed in trained rats. Our results suggested that rat heart has sufficient antioxidant enzyme capacity to cope with exercise-induced oxidative stress, and adaptive changes in antioxidant enzymes due to endurance training are limited. 相似文献