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211.
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V. Garcí a Framis J. M. Calafell J. Santal P. Andolz P. Martí nez 《Immunological investigations》1994,23(1):15-24
We employed anti-human sperm monoclonal antibodies to investigate how sperm membrane antigens are involved in gamete interactions. We have produced seven monoclonal antibodies specific for human sperm antigens, that showed reaction with mouse sperm by ELISA and by immunofluorescence. These antibodies did not react with zona pellucida or any other somatic human tissue. Some degree of toxicity was detected for oocytes at high antibody concentration and this was correlated with their inhibitory effect on fertilization. Unrelated to the degree of antigen expression or localization on sperm membrane, the antibodies showed several degrees of inhibition. The participation in sperm-zona pellucida interaction for every antigen could be evidenced by the impaired penetration of sperm caused by the presence of several concentrations of antibody. Thus, DAN-2, MOU-8 and VAC-4 inhibit mouse in vitro fertilization. 相似文献
213.
F Calero J Jimeno F Rodríguez-Escudero J Asins Codoner J Mendana J Iglesias F Murillo F Ugalde A Armas A Rementería 《European journal of gynaecological oncology》1992,13(1):83-89
We have evaluated the clinical toxicity of Epirubicin 80 mg/m2 i.v., every 3 weeks in 58 patients with FIGO III-IV endometrial adenocarcinoma or squamous uterine cervix carcinoma. The median age of the whole group was 59 years (37-77); 37 patients were previously treated with radiotherapy and two with cisplatin based chemotherapy. The median KI at entry was 80. A total of 308 courses of chemotherapy were administered with a median of 5 per patient. Overall toxicity data shows that this dose level is associated with mild haematological toxicity with only two cases having grade 3 (WHO) leukopenia. Nine patients suffered emesis in spite of prophylactic therapy and were classified as grade 3. One case presented grade four diarrhoea but the relation with the antineoplastic treatment was uncertain. One woman with hepatic dysfunction at entry had grade 3 leukopenia, developed pneumonia and died. The median total cumulative dose of EPI was 360 mg/m2 (160-880) with 19 cases exposed to cumulative doses higher than 550 mg/m2. Congestive heart failure was not observed. Our data confirm the safety of EPI at these dose levels and suggest the possibility of developing new trials with higher doses of this anthracycline analog. 相似文献
214.
Leire García Maria Bu?uales Nejat Düzgüne? Conchita Tros de Ilarduya 《European journal of pharmaceutics and biopharmaceutics》2007,67(1):58-66
In this study, an efficient non-viral gene transfer system has been developed by employing polyethylenimine (PEI 800, 25 and 22kDa) and DOTAP and cholesterol (Chol) as lipids (lipopolyplex), at three different lipid/DNA molar ratios (2/1, 5/1 and 17/1) by using five different protocols of formulation. Condensation assays revealed that PEI of 800, 25 and 22kDa were very effective in condensing plasmid DNA, leading to a complete condensation at N/P ratios above 4. Addition of DOTAP/Chol liposomes did not further condense DNA. Increasing the molar ratio lipid/DNA in the complex resulted in higher positive values of the zeta-potential, while the particle size increased in some protocols, but not in others. High molecular weight PEI (800kDa) used in the formulation of lipopolyplexes lead to a bigger particle size, compared to that obtained with smaller PEI species, whether branched (25kDa) or linear (22kDa). These vectors were also highly effective in protecting DNA from attack by DNAse I. Transfection activity was maximal by using protocols 3 and 4 and a lipid/DNA molar ratio of 17/1. These complexes showed high efficiency in gene delivery of DNA to liver cancer cells, even in the presence of high concentration of serum (60% FBS). On the other hand, complexes formed with linear PEI (22kDa) were more effective than lipopolyplexes containing branched PEI (800 or 25kDa). The complexes resulted to be much more efficient than conventional lipoplexes (cationic lipid and DNA) and polyplexes (cationic polymer and DNA). The same behaviour was observed for complexes prepared in the presence of the therapeutic gene pCMVIL-12. Toxicity assays revealed a viability higher than 80% in all cases, independently of the protocol, molar ratio (lipid/DNA), molecular weight and type of PEI. 相似文献
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M. C. Robson MD a ; L. G. Phillip MD ; D. M. Cooper RN PhD a ; W. G. Lyle MD ; L. E. Robson RN MS ; L. Odom RN ; D. P. Hill PharmD ; A. F. Hanham MD ; G. A. Ksander MS 《Wound repair and regeneration》1995,3(2):157-167
Transforming growth factor-beta(2) promotes healing in a variety of animal models and exhibits clinical effects thought to be mediated by connective tissue formation. Two clinical trials were conducted to evaluate the safety and effect of transforming growth factor-beta(2) purified from bovine bone and delivered topically to venous stasis ulcers three times per week for up to 6 weeks by means of a lyophilized collagen vehicle. The first was an open-label trial comparing transforming growth factor-beta(2) purified from bovine bone (0.5 microg/cm(2)) with a placebo consisting of lyophilized collagen vehicle-without active drug. After no safety issues arose in that trial, a prospectively randomized, closed-label, observer-blinded, three-armed trial was conducted to compare bovine transforming growth factor-beta(2) (2.5 microg/cm(2)) with the collagen matrix placebo vehicle and with a standard dressing. Standardized elastic compression was applied to all test extremities. The rate of reduction of ulcer area as measured by planimetry was the primary measure of effect. No serious safety-related events occurred in either trial. Clinical evaluation suggested that improvement in the quality and quantity of granulation tissue appeared to precede epithelialization of ulcers treated with bovine transforming growth factor-beta(2). In both studies, treatment with bovine transforming growth factor-beta(2) appeared to have a positive effect on the rate of ulcer closure, whereas ulcers in the control groups continued to exhibit impaired healing. In the open-label study, the mean rate of closure of ulcers treated with bovine transforming growth factor-beta(2) was significantly greater than that of ulcers treated with placebo. There was likewise enhanced reduction in ulcer area in the ulcers treated with bovine transforming growth factor-beta(2) in the second trial. However, because of a higher variability in patient response and a greater placebo effect, the difference was not significant. The placebo was not worse than the standard care arm, thereby showing that the vehicle is not injurious to healing. The combined results of the two trials suggest that, at doses of 0.5 to 2.5 microg/cm(2), bovine transforming growth factor-beta(2) is safe as a topically applied agent in a collagen matrix vehicle and can have a positive effect on closure of venous stasis ulcers. Large multicenter trials appear to be indicated to evaluate fully the potential utility of transforming growth factor-beta(2) in accelerating closure of chronic dermal ulcers. 相似文献
218.
Increased fibrinolytic activity is a well recognized constant finding observed during cardiopulmonary bypass (CPB). The purpose of the present work was to study and estimate the factors involved in the plasminogen activation and prekallikrein-kallikrein systems in a population of adult patients undergoing open heart surgery with CPB. Plasminogen activator activity determinations with a fibrinolytic method as well as plasminogen activation and prekallikrein-kallikrein determinations with synthetic substrates were carried out. Our results indicate that no active fibrinolysis but a fibrinolytic potential, similar to that observed in blood obtained after venous occlusion, can be demonstrated in circulating plasma during CPB. This fibrinolytic potential is related to the presence of vascular plasminogen activator released from endothelial cells by the CPB stimulus. 相似文献
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220.
抗乙肝胎盘转移因子的特异免疫活性观察 总被引:8,自引:0,他引:8
本研究由HBVM-Ab阳性胎盘提取的抗乙肝胎盘转移因子(PSTF)的特异免疫活性证明,经注射,小鼠外周血淋巴细胞明显增多,胸腺重量和指数亦显著增加,酯酶染色证明75%属T-样淋巴细胞,25%属Thy-样淋巴细胞,人白细胞或小鼠白细胞体外转移PSTF特异免疫活性、或豚鼠和小鼠体内转移PSTF特异免疫活性,再取其白细胞作白细胞粘附抑制、白细胞移动抑制、特异淋巴细胞转化、小鼠足掌注射和诱生γ-干扰素试验 相似文献