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Raoul Orvieto Irina Zagatsky Vered Yulzari-Roll Antonio La Marca Benjamin Fisch 《Gynecological endocrinology》2006,22(8):437-440
BACKGROUND: To investigate the degree of systemic inflammation, as reflected by serum C-reactive protein (CRP) levels, associated with controlled ovarian hyperstimulation (COH) with human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) agonist for the induction of final follicular maturation. DESIGN: Prospective, observational study. SETTING: An in vitro fertilization (IVF) unit of an academic medical center. PATIENTS: Twenty-four women undergoing COH and IVF with the flexible GnRH antagonist protocol were prospectively assigned to receive hCG or GnRH agonist for the induction of final follicular maturation. METHODS: Blood was drawn three times during COH for measurement of sex-steroid and CRP levels: the day on which adequate suppression was obtained (Day-0); the day of or prior to administration of hCG (Day-hCG); and (3) the day of ovum pick-up (Day-OPU). Levels were compared among the three time points in the two groups. RESULTS: No between-group differences were observed in terms of patient age, gonadotropin dosage, duration of stimulation or number of oocytes retrieved. Serum CRP levels were significantly higher on Day-OPU than on Day-hCG and Day-0, but the difference was significant only in the hCG group (p<0.03 for both). The percentage change in CRP levels after hCG administration (Day-OPU vs. Day-hCG) (96%) was higher than that after GnRH administration (23%). CONCLUSION: Administration of GnRH agonist in patients undergoing COH for IVF yields a lesser degree of systemic inflammation, as reflected by CRP levels, than hCG. 相似文献
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Integration and differentiation of human embryonic stem cells transplanted to the chick embryo. 总被引:3,自引:0,他引:3
Ronald S Goldstein Micha Drukker Benjamin E Reubinoff Nissim Benvenisty 《Developmental dynamics》2002,225(1):80-86
Human embryonic stem (ES) cells are pluripotent cells that can differentiate into a large array of cell types and, thus, hold promise for advancing our understanding of human embryology and for contributing to transplantation medicine. In this study, differentiation of human ES cells was examined in vivo by in ovo transplantation to organogenesis-stage embryos. Colonies of human ES cells were grafted into or in place of epithelial-stage somites of chick embryos of 1.5 to 2 days of development. The grafted human ES cells survived in the chick host and were identified by vital staining with carboxyfluorescein diacetate or use of a green fluorescent protein-expressing cells. Histologic analysis showed that human ES cells are easily distinguished from host cells by their larger, more intensely staining nuclei. Some grafted cells differentiated en masse into epithelia, whereas others migrated and mingled with host tissues, including the dorsal root ganglion. Colonies grafted directly adjacent to the host neural tube produced primarily structures with the morphology and molecular characteristics of neural rosettes. These structures contain differentiated neurons as shown by beta-3-tubulin and neurofilament expression in axons and cell bodies. Axons derived from the grafted cells penetrate the host nervous system, and host axons enter the structures derived from the graft. Our results show that human ES cells transplanted in ovo survive, divide, differentiate, and integrate with host tissues and that the host embryonic environment may modulate their differentiation. The chick embryo, therefore, may serve as an accessible and unique experimental system for the study of in vivo development of human ES cells. 相似文献
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Otavio A C Clark Gary H Lyman Aldemar A Castro Luciana G O Clark Benjamin Djulbegovic 《Journal of clinical oncology》2005,23(18):4198-4214
PURPOSE: Current treatment for febrile neutropenia (FN) includes hospitalization for evaluation, empiric broad-spectrum antibiotics, and other supportive care. Clinical trials have reported conflicting results when studying whether the colony-stimulating factors (CSFs) improve outcomes in patients with FN. This Cochrane Collaboration review was undertaken to further evaluate the safety and efficacy of the CSFs in patients with FN. METHODS: An exhaustive literature search was undertaken including major electronic databases (CANCERLIT, EMBASE, LILACS, MEDLINE, SCI, and the Cochrane Controlled Trials Register). All randomized controlled trials that compare CSFs plus antibiotics versus antibiotics alone for the treatment of established FN in adults and children were sought. A meta-analysis of the selected studies was performed. RESULTS: More than 8,000 references were screened, with 13 studies meeting eligibility criteria for inclusion. The overall mortality was not influenced significantly by the use of CSF (odds ratio [OR] = 0.68; 95% CI, 0.43 to 1.08; P = .1). A marginally significant result was obtained for the use of CSF in reducing infection-related mortality (OR = 0.51; 95% CI, 0.26 to 1.00; P = .05). Patients treated with CSFs had a shorter length of hospitalization (hazard ratio [HR] = 0.63; 95% CI, 0.49 to 0.82; P = .0006) and a shorter time to neutrophil recovery (HR = 0.32; 95% CI, 0.23 to 0.46; P < .00001). CONCLUSION: The use of the CSFs in patients with established FN caused by cancer chemotherapy reduces the amount of time spent in hospital and the neutrophil recovery period. The possible influence of the CSFs on infection-related mortality requires further investigation. 相似文献
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