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21.
Prednisone-Free Maintenance Immunosuppression—A 5-Year Experience   总被引:1,自引:0,他引:1  
Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good.  相似文献   
22.
Objectives  We conducted a study to determine the numbers of susuks (charm needles) and their distribution in the craniofacial region of susuk wearers, and the sex, racial affiliation, and age of the wearers. In addition, we sought to determine whether the presence of susuks posed any potential hazard to patients undergoing magnetic resonance imaging (MRI). Methods  We studied various radiographs of 33 susuk wearers (age range, 33–69 years) and investigated the most common sites of insertion in the craniofacial region. A susuk was also suspended inside a 1.5-T MRI machine to determined whether it was attracted by the machine’s magnet. Results  The largest number of susuks that we observed in the craniofacial region was 39 pins, and susuks were particularly numerous in Malay Muslim women. Other sites with susuks were the maxillofacial region (except the temporomandibular region) and the forehead. The susuks showed no ferromagnetic characteristics. Conclusions  As susuks are made from gold, they are generally biocompatible with human tissue and do not cause problems to their wearers. Gold and the other minor metal constituents found in susuks have no ferromagnetic characteristics and therefore pose no hazard to patients undergoing MRI.  相似文献   
23.
OBJECTIVE: The purpose of this study was to examine neurophysiological characteristics of dystonia patients using electromyographic soleus H-reflex methods. METHODS: Thirty normal healthy individuals were compared to 27 patients with focal (cervical) or generalized dystonia. Three H-reflex assessment methods were included: the ratio of maximum H-reflex to direct muscle potential (H/M ratio); vibration inhibition (H(v)/H(c) ratio); and H-reflex recovery curves (HRRC). RESULTS: Average H/M ratios between groups were not statistically significant. The average H(v)/H(c) ratio for the generalized dystonia group was significantly greater than the focal dystonia and normal groups. Average values of the HRRC showed the generalized dystonia group had significantly greater disinhibition than the focal dystonia and control groups during the early inhibition phase. The HRRC for the focal dystonia group was greater than normal and more similar to the generalized dystonia group during the late phases of the recovery curve. The average value of the localized late facilitation phase for the focal dystonia group was significantly greater than the control group and less than the generalized dystonia group. No differences were observed between groups for the average localized late inhibition phase of the recovery curve. CONCLUSIONS: Soleus H-reflex measures identified neurophysiologic differences between generalized dystonia, cervical dystonia and normal conditions. SIGNIFICANCE: This methodology enables analysis of the underlying characteristics of dystonic pathologies using soleus H-reflex methods rather than upper extremity H-reflex techniques.  相似文献   
24.
OBJECTIVE: The aim of this study is to investigate dose-dependent effect of the topical application of methotrexate (MTX) in rats on the normal nasal mucosa, liver tissue, liver enzymes, and hemoglobin levels. STUDY DESIGN: Preclinical animal study. SETTING: Twenty male adult wistar albino rats were randomly divided into 4 groups (n=5). A single puff of MTX (2.5 microg) was applied to both nasal cavities 2 times a day. The animals were given MTX 1 day a week in group 1, 3 days a week in group 2, and 5 days a week in group 3. Control group animals were given 1 puff of physiologic saline to both nasal cavities 5 days a week and 2 times a day. After 28 days, liver biopsies, blood samples, and 5 nasal mucosal biopsies were taken. Histological examination was made with respect to certain parameters semiquantitatively (grade 0-3). The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and hemoglobin counts were studied from blood samples. RESULTS: There are no statistically significant differences with respect to histopathological parameters between the control group and the groups 1-3 (P>0.05). Histopathological examination of liver tissue did not reveal any evident difference between the control and study groups. Mean AST and ALT as liver function tests and hemoglobin counts were within normal limits. Topical application of MTX at these doses has no toxic effect on the nasal mucosa, the liver tissue, AST and ALT levels, and hemoglobin level. CONCLUSIONS: These results have been encouraging to investigate use of the topical application of MTX in nasal manifestation of autoimmune disease or addition of the topical application of MTX to the steroid treatment in cases with massive nasal polyposis resistant to steroids and prone to recurrence.  相似文献   
25.
By use of primers specific to conserved regions of the rRNA gene cluster, a discrete amplicon of approximately 5 kb was amplified by PCR from all 21 bacterial genera investigated. Subsequent endonuclease digestion of the PCR product with HaeIII distinguished between the three species of the human pathogen Francisella spp. on the one hand and four clinically relevant genomic groups of Acinetobacter spp. on the other hand. The described technique has the potential as a rapid method for discriminating between closely related species that are of clinical importance.  相似文献   
26.
27.
The limb-girdle muscular dystrophies are a clinically and geneticallyheterogeneous group of disorders. We have ostudied two largeinbred families of different ethnic origin and excluded linkageto LGMD2 on chromosome 15q and SCARMD on chromosome 13. Proceedingto a genomic linkage search, we have now identified linkageto markers D2S134 and D2S136 on chromosome 2p (maximum lod score3.57 at zero recombination). The phenotype in the two familieswas similar, with onset in the pelvic girdle musculature inthe late teens and usually relatively slow progression. Thiswork Identifies a second locus for autosomal recessive limb-girdlemuscular dystrophy.  相似文献   
28.
In humans the majority of the CD3+ T cells usually express an alpha/beta T cell receptor (TcR) and a minority express a gamma/delta TcR. The CD3+ TcR alpha/beta and CD3+ TcR gamma/delta cells from blood of the patients with schistosomiasis with carcinoma of the urinary bladder (SCB) were analyzed for phenotype, activation, secretion of interleukin 2 (IL 2). B cell growth factor (BCGF) and B cell differentiation factor (BCDF), as well as for autologous (AMLR) and allogeneic (MLR) mixed lymphocyte reaction. Patients with SCB had a highly increased percentage of CD3+ TcR gamma/delta and a decreased percentage of CD3+ TcR alpha/beta T cells in their circulation. These CD3+ TcR gamma/delta T cells expressed the CD25 (IL 2 receptor), CD38, CD71 (transferrin receptor) and HLA-DR activation antigens at a higher intensity after in vitro stimulation with recombinant IL 2, phytohemagglutinin and soluble egg antigen (from Schistosoma haematobium). The SCB patients' CD3+ TcR gamma/delta T cells were highly deficient in secretion of IL 2 but produced highly elevated levels of BCGF and BCDF. On the contrary, both BCGF and BCDF activities of the CD3+ TcR alpha/beta T cells were decreased. Moreover, CD3+ TcR gamma/delta T cells demonstrated highly deficient AMLR and MLR activity. These observations suggest a possible role of CD3+ TcR gamma/delta T cells in the immune response and the disease pathogenesis in human schistosomiasis infections.  相似文献   
29.
One strategy for improving resistance to opportunistic pathogens is to determine host cellular responses during the invasion process and upregulate those responses that are relevant to host defense mechanisms. Within this context, we have shown previously that invasion of endothelial cells by Candida albicans in vitro causes increased production of prostaglandins. As a prerequisite for modulating endothelial cell prostaglandin production, we now characterize the mechanisms through which this process occurs. Endothelial cell invasion by C. albicans appeared to stimulate the conversion of arachidonic acid into prostaglandins by upregulating the synthesis of endothelial cell cyclooxygenase and increasing the activity of the endothelial cell phospholipase. The enhanced activities of these two enzymes were independent of calphostin C-sensitive protein kinase C and resulted in the increased production and extracellular secretion of prostaglandin I2 (PGI2), PGF2 alpha, and PGE2. The secretion of these prostaglandins had no effect on the amount of endothelial cell injury induced by C. albicans. The role of the increased prostaglandin secretion by endothelial cells is likely related to modulation of the leukocyte response at the candida-leukocyte-endothelial cell interface.  相似文献   
30.
Subsets of T cells express different isoforms of the leukocyte common antigen CD45; those expressing the glycoprotein 220 isoform (CD45RA) have been characterized as naive in their response to antigens, and those expressing the glycoprotein 180 isoform (CD45RO) as memory T cells. The association between the rejection status of human cardiac allograft recipients and the relative infiltration of the CD45 subsets of both CD8+ and CD4+ T cells was examined using two-color immunohistological labeling techniques on 33 heart transplant biopsies, categorized by routine histological and clinical criteria as mild (requiring no treatment) or moderate (requiring antirejection therapy) rejection. Double-labeling was performed using pairs of monoclonal antibodies to define the following populations: CD4+ CD45RA+, CD4+ CD45RO+, CD8+ CD45RA+, and CD8+-CD45RO+. The number of cells per high-power field (HPF) for each of these cell subsets was counted in every biopsy. In cases with mild rejection, infiltration was predominant for CD4+ CD45RA+ cells (median = 5.0 cells/HPF) relative to CD4+ CD45RO+ (3.12 cells/HPF), CD8+ CD45RA+ (2.14 cells/HPF), and especially CD8+ CD45RO+ (1.22 cells/HPF) populations. In cases with moderate rejection, all four subpopulations increased but were essentially equivalent in intensity, such that in comparison to cases with mild rejection, the smallest increase was seen for CD4+ CD45RA+ cells (6.67 cells/HPF, P < 0.09) and the greatest for CD8+ CD45RO+ cells (7.00 cells/HPF, P < 0.002). A majority of CD8 cells expressed CD45RA in 14 of 16 (88%) cases of mild rejection compared to only 2 of 17 cases of moderate rejection. Moreover, the ratio of CD45RO+ to CD45RA+ cells in each biopsy was higher in moderate versus mild rejection for both CD4 (median ratios = 1.13 versus 0.68, respectively; P < 0.008) and CD8 (1.43 versus 0.58, respectively; P < 0.005) subsets. A majority of T cells expressed CD45RO in cases of moderate rejection (11 of 14 or 79%), compared to only 1 of 13 (8%) cases of mild rejection. These findings indicate that during generally self-limited mild acute cardiac allograft rejection there is a predominance of naive CD45RA+ T cells, especially of the CD4 phenotype, whereas during moderate rejection there is a significant shift toward activated CD45RO+ T cells, especially in the CD8 population.  相似文献   
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