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21.
BACKGROUND: Cysteinyl leukotrienes play a disease-regulating role in rhinosinusitis and asthma, particularly aspirin-sensitive disease. They act through 2 G-protein coupled receptors termed cysteinyl leukotriene type 1 receptor (cysLT 1 ) and cysteinyl leukotriene type 2 receptor (cysLT 2 ). We previously compared expression of cysLT 1 on mucosal leukocytes in patients with aspirin-sensitive and aspirin-tolerant rhinosinusitis. OBJECTIVE: To compare expression of cysLT 1 and cysLT 2 on leukocytes, mucus glands, and epithelium in 32 patients with chronic polypoid rhinosinusitis (21 aspirin-sensitive, 11 aspirin-tolerant) and 9 normal controls. METHODS: Total numbers of CD45 + leukocytes, percentages of these cells expressing cysLT 1 or cysLT 2 , and percentages of the total epithelial and glandular areas expressing cysLT 1 or cysLT 2 were measured in sections of nasal biopsies by using immunohistochemistry and image analysis. RESULTS: The percentages of mucosal CD45 + leukocytes expressing cysLT 1 were significantly ( P < .0001) elevated in the aspirin-sensitive but not the aspirin-tolerant patients compared with the controls. In contrast, the percentages of leukocytes expressing cysLT 2 did not differ significantly in the 3 groups. On epithelial and glandular cells, expression of cysLT 2 significantly exceeded that of cysLT 1 in both the patients with rhinosinusitis and the controls ( P < or = .004), although there was no significant difference in the expression of either receptor in the patients with rhinosinusitis (aspirin-sensitive or aspirin-tolerant) and the controls. CONCLUSION: Although cysLT 1 expression predominates on inflammatory leukocytes in patients with aspirin-sensitive rhinosinusitis, the effects of cysteinyl leukotrienes on glands and epithelium may be mediated predominantly through cysLT 2. This has potentially important therapeutic implications.  相似文献   
22.
We have previously observed the repeated presence of low but detectable amounts of the trophoblast marker pregnancy-specific beta1-glycoprotein (SP1) in the serum of some women undergoing in-vitro fertilization (IVF) treatment around the time of oocyte retrieval. The occurrence of these signals seemed to be restricted to a defined group of patients which also showed a lower pregnancy success rate in a preliminary study. To test our hypothesis we have analysed 173 consecutive cycles leading to an embryo transfer. Fifty-four cycles (31%) had a serum SP1 level of at least 0.1 ng/ml between days embryo transfer -5 and embryo transfer (group A). Five pregnancies were obtained in this group (pregnancy rate = 9.3%), while in group B, defined by the absence of detectable SP1 before embryo transfer (119 cycles), 36 ongoing pregnancies were achieved (30.3%). Ten of the 41 pregnancies were achieved in 33 first-time non-pregnant patients undergoing further attempts during the study period. Again the pregnancy rate was higher in the first-time group B women (9/23 versus 1/10 for group A). Patients tended to remain in their groups A or B, the latter being associated with a better immediate as well as subsequent chance for pregnancy. Group A cycles had a significantly lower endometrial thickness two days before oocyte retrieval than group B (P = 0.0011). We postulate that the presence of an unknown, maternal and progesterone- or follicle stimulating hormone-independent factor in some patients could stimulate tonic ectopic SP1 synthesis and at the same time negatively influence endometrial development.   相似文献   
23.
We have developed a four-dimensional computed tomography (4D CT) technique for mapping breathing motion in radiotherapy treatment planning. A multislice CT scanner (1.5 mm slices) operated in ciné mode was used to acquire 12 contiguous slices in each couch position for 15 consecutive scans (0.5 s rotation, 0.25 s between scans) while the patient underwent simultaneous quantitative spirometry measurements to provide a sorting metric. The spirometry-sorted scans were used to reconstruct a 4D data set. A critical factor for 4D CT is quantifying the reconstructed data set quality which we measure by correlating the metric used relative to internal-object motion. For this study, the internal air content within the lung was used as a surrogate for internal motion measurements. Thresholding and image morphological operations were applied to delineate the air-containing tissues (lungs, trachea) from each CT slice. The Hounsfield values were converted to the internal air content (V). The relationship between the air content and spirometer-measured tidal volume (v) was found to be quite linear throughout the lungs and was used to estimate the overall accuracy and precision of tidal volume-sorted 4D CT. Inspection of the CT-scan air content as a function of tidal volume showed excellent correlations (typically r>0.99) throughout the lung volume. Because of the discovered linear relationship, the ratio of internal air content to tidal volume was indicative of the fraction of air change in each couch position. Theoretically, due to air density differences within the lung and in room, the sum of these ratios would equal 1.11. For 12 patients, the mean value was 1.08 +/- 0.06, indicating the high quality of spirometry-based image sorting. The residual of a first-order fit between v and V was used to estimate the process precision. For all patients, the precision was better than 8%, with a mean value of 5.1% +/- 1.9%. This quantitative analysis highlights the value of using spirometry as the metric in sorting CT scans. The 4D reconstruction provides the CT data required to measure the three-dimensional trajectory of tumor and lung tissue during free breathing.  相似文献   
24.
We have previously shown that activated C1s complement and activated T cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation of desLys58 beta2m. This process can specifically be inhibited by C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte cultures inhibited proliferation, the development of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell- mediated immune functions.   相似文献   
25.
26.
Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.   相似文献   
27.
p53蛋白的免疫亲和层析纯化   总被引:2,自引:0,他引:2  
钟叔平  曹亮 《免疫学杂志》1997,13(2):122-124,139
建立了p53单克隆抗体pAb1801的免疫亲和层极法纯化p53蛋白,所纯化的p53蛋白经Western Blot(ECL法)检测证明:用此法从p53阳性的SW480细胞中分离到p53蛋白。银染显示pH2.0甘氨酸缓冲液比pH2.8的甘氨酸缓冲液洗脱效果好,这种方法的建立将为分离肿瘤细胞中引起p53蛋白功能失活和研究肿瘤发生机制提供一种有效途径。  相似文献   
28.
Adrenoleukodystrophy (ALD) is an X-linked disorder caused by a defect in the metabolism of long chain fatty acids leading to demyelination, neurodegeneration, and death. The disease typically presents in young boys and adolescent boys. Allogeneic bone marrow transplantation has been used to halt progression of the disease. However, many patients lack suitable HLA- matched related donors and must rely on unmatched donors for a source of stem cells. The purpose of this study was to evaluate outcomes of unrelated donor umbilical cord blood transplantation after chemotherapy-based myeloablative conditioning and retrospectively determine if baseline studies correlate and help predict outcome. Between November 22, 1996, and November 3, 2005, 12 boys with X-linked ALD who lacked HL- matched related donors were referred to Duke University Medical Center for transplantation. These children were conditioned with myeloablative therapy including busulfan, cyclophosphamide, and antithymocyte globulin before receiving umbilical cord-blood transplants from unrelated donors. Baseline studies of neurophysiologic, neuroimaging, and neurodevelopmental status were performed and patients were subsequently evaluated for survival, engraftment, graft-versus-host disease, and neurodevelopmental outcomes. A substudy evaluated whether baseline neuroimaging and neurophysiologic studies correlated with cognitive and motor function and if these studies were predictive of posttransplantation outcomes. The umbilical cord blood grafts had normal levels of very long chain fatty acids. They delivered a median of 6.98 x 10(7) nucleated cells per kilogram of recipient body weight and were discordant for up to 4 of 6 HLA markers. Neutrophil engraftment occurred at a median of 22.9 days after transplantation. Three patients had grade II-IV acute graft-versus-host disease; 2 had extensive chronic graft-versus-host disease. Cumulative incidence of overall survival of the group at 6 months is 66.7% (95% confidence interval 39.9-93.3%). Median follow-up was 3.3 years (range 12 days to 6.3 years). As previously reported with bone marrow transplantation, symptomatic patients faired poorly with lower survival and rapid deterioration of neurologic function. This study included 3 patients transplanted at a very young age (2.6-3.5 years) before the onset of clinical symptoms who continue to develop at a normal rate for 3-5 years posttransplant. Although baseline Loes scores correlated with cognitive and motor outcome, neurophysiologic studies failed to show statistically significant differences. Transplantation of boys with X-linked ALD using partial HLA-matched umbilical cord blood yields similar results to those previously reported after bone marrow transplantation. Superior outcomes were seen in neurologically asymptomatic boys less than 3.5 years of age at the time of transplantation. Baseline Loes scores were a strong predictor of cognitive and motor outcome.  相似文献   
29.
Human mini-chromosomes in mouse embryonal stem cells   总被引:3,自引:2,他引:3  
We have introduced human mini-chromosomes of 4 Mb and approximately 15 Mb in size into mouse embryonal stem cells. Although these human mini- chromosomes are stable in hamster and chicken cells, they re-arrange or segregate aberrantly in the embryonal stem cells and are rapidly lost in the absence of selection. However, one of the mini-chromosomes re- arranged, acquired mouse centromeric sequences and was then stably maintained for at least 60 population doublings in culture. This mini- chromosome, which is 4 Mb in size, is a candidate for a mouse germ line chromosome vector.   相似文献   
30.
Prenatal cytogenetic analysis of 71 fetuses conceived by intracytoplasmic sperm injection (ICSI) resulted in the detection of nine (12.7%) chromosome aberrations including two cases of 47,XXY, four cases involving a 45,X cell line and three autosomal trisomies. Molecular analysis of the parental origin of the deleted or supernumerary chromosome was performed by using polymorphic microsatellite markers. Six cases involving a sex chromosome abnormality were found to be of paternal origin while the two trisomic cases that could be analysed were of maternal origin. Two cases involved the same infertile couple who had two consecutive ICSI pregnancies terminated because of a chromosome abnormality. The replaced embryos in both cases originated from a single batch of ICSI fertilized oocytes of which part was used to initiate the first pregnancy and part was cryopreserved and used to initiate the second pregnancy.   相似文献   
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