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21.
Alport syndrome: HLA association and kidney graft outcome.   总被引:1,自引:0,他引:1  
Alport syndrome (AS) is a genetic disease of type IV collagen involving non-homogeneous patterns of inheritance characterized clinically by the presence of progressive haematuric nephritis leading to end-stage renal disease (ESRD), hearing loss and/or ophthalmologic abnormalities. The aim of this study was to investigate, in a cohort of AS patients who had undergone a kidney graft (KG) or who were still on a waiting list for a KG, (a) whether there is a correlation between AS and HLA antigen expression, and (b) long-term graft outcome in transplant patients. The AS cohort was represented by 34 ESRD patients, of whom 25 received a KG and the remaining nine were still on a waiting list. AS transplant patients represented 2.78% of 899 first KGs performed at our centre (Transplantation Department at S. Martino Hospital, Genoa) between 1983 and 2002. Grafts were procured from cadaveric donors in 18 cases and from living, related donors in seven cases. All AS transplant patients had a post-transplant follow-up period of at least 12 months. Results showed that: (i) the frequency of the HLA-DRB1*16 antigen was significantly increased in the whole AS cohort as compared to 128 healthy subjects (HS) (corrected P-value 0.0026; relative risk 7.20) as well as to 232 non-AS ESRD patients on a waiting list for KG (corrected P-values 0.0156; relative risk 4.67); (ii) 5- and 10-year graft survivals in the AS transplant patients were 80 and 73%, respectively, and did not differ from those of a control group represented by 25 non-AS KG recipients matched for sex, age, number of HLA mismatches and immunosuppressive treatment. Increased frequency of HLA-DRB1*16 in AS patients may reflect a linkage disequilibrium with genes coding for collagen synthesis.  相似文献   
22.
Outcomes of hematopoietic cell transplantation are steadily improving. New techniques have reduced transplant toxicities, and there are new sources of hematopoietic stem cells from unrelated donors. In June 2007 the Blood and Marrow Transplant Clinical Trials Network convened a State of the Science Symposium of more than 200 participants in Ann Arbor to identify the most compelling clinical research opportunities in the field. This report summarizes the symposium's discussions and identifies eleven high priority clinical trials that the network plans to pursue over the course of the next several years.  相似文献   
23.
IgA deficiency (IgA-D) represents the most common immunodeficiency syndrome of infancy. In most cases IgA-D represents an isolated immunological disorder, while sometimes it is associated with IgG subclass deficiency or with the presence of autoantibodies. We investigated the pattern of association of IgA-D with DRB1 and DQB1 loci of the HLA region by DNA molecular typing, which allows the identification of previously serologically undefined specificities. We also compared the gene frequency of DRB1 and DQB1 allelic variants between IgA-D subjects with or without serum autoantibodies. Our results indicate that the gene frequency of the DRB1*0102 subtype and of the DRBP0102, DQB1*0501 haplotype is significantly higher in IgA-D than in the general population. Furthermore, the IgA-D subjects with autoantibodies showed a positive association with DR4 and DR13 subtypes, thus supporting the hypothesis that genetic factors are also involved in the association between IgA-D and autoantibodies.  相似文献   
24.
The aim of the study was to estimate the sensitivity of a brief self-paced visual search task to increased levels of sleepiness as a consequence of 40 h of sleep deprivation. Time-of-day effects on this task, on subjective sleepiness and on oculomotor performance changes, were also assessed. Eight normal subjects slept for three nights in the laboratory (adaptation, baseline, recovery). Baseline and recovery nights were separated by a period of 40 h of continuous wakefulness, during which subjects were tested every 2 h from 10:00 to 22:00 h on both days preceding and following the sleep deprivation night, as well as from 24:00 to 08:00 h during the deprivation period. At the same time, subjects filled in a visual analogue sleepiness scale and the Stanford Sleepiness Scale (SSS). As regards cognitive performance, significant effects were found on speed measures, while accuracy was not affected. The number of explored rows was higher after the baseline night than after the sleepless night, and showed a consistent time-of-day trend. Omissions ratio (OR), false positives ratio (FPR) and hits ratio (HR) did not show any significant effect. Subjective ratings of sleepiness varied according to speed measures, being affected by sleep deprivation and time of day. Since similar effects were found with an oculomotor task, detrended functions for all variables across the 40 h of continuous wakefulness were calculated. A circadian effect was found, in which speed measures seem to be more affected than accuracy ones in both visual search and oculomotor tasks. It is concluded that 40 h of prolonged wakefulness significantly impairs performance in a brief cognitive visual search task. Such a performance worsening is evident on speed, but not on accuracy indices, and is strictly related to the deterioration of oculomotor performance, indicating a clear circadian effect.  相似文献   
25.
Alloreactive clones expressing T cell receptor (TcR) gamma/delta were derived by limiting dilution from CD3+ CD4- CD8- WT31- populations stimulated in allogeneic mixed lymphocyte culture. These clones specifically lysed phytohemagglutinin-induced blast cells bearing the stimulating alloantigens, whereas they had no effect on autologous or allogeneic unrelated target cells. Analysis of the reactivity with monoclonal antibodies (mAb) specific for two different subsets of TcR gamma/delta (BB3 and delta-TCS-1) showed that five out of nine clones were BB3+, whereas the remaining reacted with delta-TCS-1. Therefore, we can conclude that both subsets of TcR gamma/delta+ cells are able to specifically recognize and lyse allogeneic cells. mAb directed against the CD3-TcR gamma/delta molecular complex strongly inhibited the specific cytolytic activity of TcR gamma/delta+ clones, whereas they had no effect on the lysis of the natural killer-sensitive K-562 target cells mediated by the same clones. An alloreactive delta-TCS-1+ clone (LM12) was further characterized for its specificity. LM12 clone had been derived after stimulation in mixed lymphocyte culture against donor M.M. (HLA typing: Aw68, 24; B35, w55; DR1, 7). The analysis of a large panel of phytohemagglutinin-induced target cells revealed that only the HLA-A24+ target cells were lysed. The direct evidence that the A24 molecule represented the restriction element was provided by experiments using A24-transfected murine P815 target cells. Thus, clone LM12 efficiently lysed A24-transfected P815 cells, but not the same cells untransfected or transfected with the Cw3 gene. Therefore, it appears that polymorphic determinants of class I major histocompatibility complex molecules can be the target of TcR gamma/delta+ alloreactive cell recognition.  相似文献   
26.
Summary Recent observation of one patient suffering from dysphagia lusoria has suggested critical review of treatment of the symptomatic aberrant right subclavian artery. Surgical correction of such an anomaly is difficult and may produce serious complications, and is not always successful. Endoscopic dilatation of the oesophageal stricture, even though it might only produce temporary relief of dysphagia, represents a valid therapeutical alternative because of its favourable cost/benefit ratio, low incidence of complications and patient acceptability.  相似文献   
27.
A Ferrara  Y Atakent 《Medical care》1986,24(2):179-187
A reduction in newborn (NB) mortality is contingent on efforts of NB stabilization. The authors attempted to quantify stabilization into a score, the neonatal stabilization score (NSS) that correlates with outcome. The population for the study comprised 192 transported NBs who weighed less than 1,000 g at birth moved from level 1 hospitals in New York City during 5 years, 1977-1981. The NSS score was based on five components: vital signs, laboratory investigations, respiratory support, I.V. fluid administration, and specific managements. Each was rated 0, 1, or 2. A maximum score of 10 indicated excellent stabilization. Analyses for the validity and reliability of the NSS included the Mantel-Haenszel test (which controlled for birth weight and Apgar) and measurement of interrater agreement "k" (kappa statistic). Mortality rates were lower in those with higher NSS and odds of death were 2.39 times greater in NB with low NSS (chi 2 = 5.16; P less than 0.025). The calculated index of agreement k on 16 charts represented an excellent agreement beyond chance (k = 0.76, P less than 0.01).  相似文献   
28.
We conducted a serologic survey among dogs and cats in Italy to detect antibodies against severe acute respiratory syndrome virus 2 (SARS-CoV-2). We found that SARS-CoV-2 seroprevalence was higher among cats (16.2%) than dogs (2.3%). In addition, seroprevalence was higher among animals living in close contact with SARS-CoV-2–positive owners.  相似文献   
29.
PURPOSE: A retrospective analysis of 48 patients treated over a 20-year period (March 1973–April 1993) was undertaken to assess the results of our practice of early surgical intervention in suppurative complications of perianal Crohn's disease. METHODS: All patients were either seen in the office within the last six months or contacted by phone. RESULTS: The average age of our patients was 30 years at initial diagnosis. Thirty-four patients (71 percent) initially presented with intestinal disease and four (8 percent) with only perianal disease. Thirteen patients (27 percent) initially presented with simultaneous intestinal and perianal disease. The various fistulas at initial presentation included 8 intersphincteric (17 percent), 14 transphincteric (29 percent), 11 complex or multiple (23 percent), 5 rectovaginal (10 percent), and 2 unclassified, for a total of 40 patients. Eight patients (17 percent) presented with only an abscess. Eighty five percent of our patients healed after their first procedure, with an average time to heal of 2.8 months. Thirteen (27 percent) patients had recurrences after initial healing of their wounds. The mean time to recurrence after healing was 5.25 years. Fifty-four percent of our recurrences (7 patients) were treated by incision and drainage of an abscess only. Seven of 13 recurrences healed after the second procedure (54 percent), and 5 of 6 healed after a third procedure (83 percent). Only seven (14 percent) of our patients underwent a proctocolectomy during the study period, through September, 1993. Our overall probability of avoiding proctectomy and healing perineal wounds of 86 percent is consistent with published literature. CONCLUSIONS: Early aggressive surgical management of suppurative complications of perianal Crohn's disease before complex management problems ensue results in a high incidence of healing and a low risk of subsequent proctectomy.  相似文献   
30.
Ajoene (CAS 92284-99-6), an organic trisulphur originally isolated from garlic, has an antimycotic activity which has been widely demonstrated both in vitro and in vivo. The objective of this work was to compare the safety and effectiveness of ajoene (0.6%, gel) with terbinafine (CAS 91161-71-6) (1%, cream) for the treatment of tinea corporis and tinea cruris. The patients selected were 60 soldiers with clinical and mycological diagnosis of either dermatophytosis. They were distributed at random in two treatment groups, one treated with ajoene at 0.6% and the other with terbinafine at 1%. All patients were evaluated clinically and mycologically 30 and 60 days after completion of the treatment, which was considered effective when clinical signs and symptoms had disappeared and the mycological cultures were negative. Thirty days after treatment, the percent healing rate was 77 and 75 for the groups treated with ajoene and terbinafine, respectively. Sixty days after treatment, the healing rate 73% and 71% for the groups treated with ajoene and terbinafine, respectively. These results and those obtained in previous studies confirm that ajoene is a new agent for the topic treatment of superficial mycoses, and for the first time show the therapeutic usefulness of an inhibitor of phospholipids biosynthesis in eukaryotes.  相似文献   
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