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Atopic asthma is characterized by excessive T helper 2 (Th2)-like immunity to allergens in the bronchial mucosa. The Th2-cytokine interleukin (IL)-4 induces IgE production, while the Th2-cytokine IL-5 promotes eosinophilic inflammation in the airways of asthmatics. Most asthmatics are atopic, but a subgroup is non-atopic. We hypothesize that allergen-induced Th2, particularly IL-5, responses can be observed in peripheral blood in both atopic and non-atopic asthmatic children but not in healthy control children. The aim of the present study was to determine IL-4, IL-5, IL-9, IL-10, IL-13 and IFN-γ secretion induced from peripheral blood mononuclear cells (PBMC) by a broad panel of inhalant allergens (timothy, cat, birch, dog and house dust mite) in asthmatic children with and without sensitization. The study included 13 atopic asthmatic, 5 non-atopic asthmatic, and 12 non-atopic non-asthmatic children. PBMC were stimulated with allergens and cytokine production was measured with enzyme-linked immunosorbent assay (ELISA). Higher levels of cat and dog antigen-induced IL-5 release were more commonly observed in both atopic and non-atopic asthmatics than in controls. Children with atopic, but not non-atopic, asthma produced higher levels of allergen-induced IL-4 and IL-9 than controls. Non-atopic asthmatics produced more IL-10 than atopic asthmatics after cat stimulation. High levels of eosinophilia-associated IL-5 responses are induced by cat and dog allergen in both atopic and non-atopic asthmatic children. The Th2 cytokines IL-4 and IL-9 were associated only with atopic asthma, probably due to their IgE-inducing properties.  相似文献   
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PURPOSE: Current combination treatment strategies in malignancy are designed to evaluate the use of cytotoxic drugs and antiangiogenic agents. Endostatin, a fragment of collagen XVIII, specifically inhibits proliferation, migration, and differentiation of endothelial cells in vitro as well as angiogenesis and tumor progression in in vivo models. In this study, we determine the antitumor effect of rhEndostatin administered alone or in combination with Adriamycin against established orthotopic murine mammary carcinoma. EXPERIMENTAL DESIGN: Mice bearing orthotopically established DA-3 mammary adenocarcinoma tumors received varying doses of rhEndostatin alone and in combination with Adriamycin to assess tumor growth inhibition. Additional studies of this in vivo combination included a determination of Adriamycin-induced cardiotoxicity and in vitro effects on human umbilical vein endothelial cell proliferation and cord formation. RESULTS: For single-agent activity, optimal tumor growth inhibition was observed after s.c. administration of 50 mg/kg/day rhEndostatin or 5 mg/kg Adriamycin injected i.v. every 4 days. Combination of Adriamycin with optimal or suboptimal doses of rhEndostatin resulted in synergistic inhibition of DA-3 tumor growth. Importantly, unlike other antiangiogenic agents, rhEndostatin did not exacerbate the cardiotoxicity of Adriamycin. The synergistic interaction between rhEndostatin and Adriamycin was also observed in vitro for inhibition of human umbilical vein endothelial cell proliferation and inhibition of cord formation. CONCLUSIONS: These data suggest that the synergy observed with rhEndostatin in combination with Adriamycin is exerted at the level of the endothelial cell and can result in enhanced tumor growth inhibition. The potential benefit of Adriamycin used in combination with rhEndostatin is being considered for clinical evaluation.  相似文献   
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Purpose: Our purpose was to assess the endocrine status of women with polycystic ovaries (PCO) undergoing IVF, and to compare oocyte quality with endocrine markers of the syndrome, in an attempt to define a subpopulation with poor quality oocytes. Methods: This was a retrospective study. Patients were first endocrinologically analyzed: serum levels of androgens (T, androstenedione, DHEAS), FSH, and LH as well as glucose and insulin after an oral glucose tolerance test (OGTT) were recorded and are expressed as absolute values and area under the curve (AUC). Subsequently, they were followed over a 2-year period in which patients underwent several attempts of IVF as well as serving as oocyte donors. Patients were divided into three groups: group I (n=4) was women who displayed embryos unable to implant in 15 IVF cycles and 10 ovum donation cycles in which they served as donors; group II (n=16) was PCO patients in whom IVF (n=38) and/or oocyte donation cycles (n=42) resulted in pregnancies; and group III (n=13) was IVF patients with normal appearance of the ovaries by ultrasound. The endocrine status was compared with the IVF results. Results: There was no difference among groups in the endocrinological parameters tested, except for the OGTT which identified women in group I as having higher serum glucose and insulin levels than patients in groups II and III. Similarly, the OGTT showed higher serum glucose values in group II compared to group III. Women in group I were also obese. Patients in group III were older than PCO patients and needed more gonadotropins to reach an ovarian response which resulted in a reduced number of oocytes retrieved. Fertilization was also impaired in group I, in which no pregnancy was recorded. Conclusions: This study shows that there is a particular subgroup of PCO patients with lower fertilization rates and embryos unable to implant. These patients are obese and nonhyperandrogenic and show derangements of insulin secretion.  相似文献   
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Purpose: Our purpose was to detect aneuploidy for chromosomes 13, 16,18, 21, 22, X, and Y in preimplantation embryos from patients with a history of unexplained recurrent miscarriage. Methods: Three patients with a history of unexplained recurrent spontaneous abortion were included in this study. Embryos were biopsied at the eight-cell stage, individually fixed on slides, and processed for fluorescent in situ hybridization (FISH). A multiple FISH protocol for seven chromosomes pairs (13, 16, 18, 21, 22, X, and Y) has been developed. Results: A total of 39 embryos was studied with the multiple FISH protocol developed. Successful analysis of the biopsied embryos was achieved within the time limits usually allowed in a preimplantation diagnosis program. Analysis of the blastomeres showed that 17 embryos were chromosomally normal for the probes used, 16 embryos were aneuploid, and in 6 embryos no informative results were obtained. Conclusions: In the patients studied, a large proportion of embryos (41%) exhibited chromosomal abnormalities for the probes used. Preimplantation diagnosis to screen for chromosome abnormalities could be a feasible approach to improve the possibility of successful pregnancy in these couples.  相似文献   
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