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41.
HLA matching between the donor and recipient improves the success of unrelated hematopoietic stem cell transplantation (HSCT). Because many patients in need of an unrelated transplant have only donors with mismatch, information is needed to evaluate the limits of HLA mismatching. We examined the association of survival, acute graft-versus-host disease (aGVHD) and relapse with HLA-A, -B, -C, -DRB, -DQB1, and -DPB1 mismatching in 334 patients coming from 12 French transplant centers and who received a non-T cell-depleted bone marrow graft from an unrelated donor. All patients were prepared with the use of myeloablative conditioning regimens. Our analyses demonstrate negative effects of HLA mismatching for either HLA-A, -B, -C, -DRB1, or -DQB1 loci on survival. Multivariate Cox analyses showed that a single mismatch was associated with a significant decrement in survival (P=.046, hazard ratio [HR]=1.41, confidence interval [CI] 95% 1.1-1.98). The presence of multiple mismatches was worse for survival (P=.003, HR=1.91, CI 95% 1.26-2.91) and severe aGVHD (grade III-IV) (P=.002, HR=2.51, CI95% 1.41-4.46). The cumulative incidences of aGVHD and relapse in those HLA-A, -B, -C, -DRB1, and -DQB1 identical pairs with 2, 1, or 0 DPB1 incompatibilities were 63%, 50%, and 51%, and 12%, 27%, and 20%, respectively, but these differences were not statistically significant. Similar differences of aGVHD and relapse, but not statistically significant, were observed in those HLA-A, -B, -C, -DRB1, and -DQB1 identical pairs with DPB1 disparities classified into permissive or nonpermissive mismatches according to Zino's classification based on a hierarchy of the immunogenicity of the HLA-DP molecules. "Missing killer cell immunoglobulin-like receptor (KIR) ligand" evaluated on the presence of HLA-C1, -C2, and Bw4 groups in the recipients was not associated with aGVHD, survival, and relapse in this cohort of non-T cell-depleted HSCT.  相似文献   
42.
In this work, using bronchoalveolar lavage fluids (BALF), we demonstrated the presence of complement within airways by assaying hemolytic activity of the whole classical pathway (CH50) and by measuring the complement component C2 (C2H50). Patients with sarcoidosis, patients with idiopathic pulmonary fibrosis (IPF), and healthy control subjects were compared. No CH50 activity was found in BALF from healthy control subjects (n = 9), but some activity (mean, 20 CH50) was associated with IPF (n = 7). Complement activities ranged from 40 to 554 CH50 in patients with sarcoidosis (n = 27). During the treatment, complement activity decreased in BALF from the few patients in our series who received corticotherapy. C2 hemolytic activity was detected in BALF from the normal control group (in the absence of CH50 activity). In the sarcoidosis and IPF groups when CH50 was present, the variations in the C2/CH50 ratio were studied. The high ratio observed in BALF from patients with sarcoidosis and a chronic derangement of alveolar structure suggests either an increased C2 production or an alternative complement pathway (C2-independent) activation within their lungs.  相似文献   
43.

Purpose.

Breast cancer is the most common malignancy among women in Lebanon and in Arab countries, with 50% of cases presenting before the age of 50 years.

Methods.

Between 2009 and 2012, 250 Lebanese women with breast cancer who were considered to be at high risk of carrying BRCA1 or BRCA2 mutations because of presentation at young age and/or positive family history (FH) of breast or ovarian cancer were recruited. Clinical data were analyzed statistically. Coding exons and intron-exon boundaries of BRCA1 and BRCA2 were sequenced from peripheral blood DNA. All patients were tested for BRCA1 rearrangements using multiplex ligation-dependent probe amplification (MLPA). BRCA2 MLPA was done in selected cases.

Results.

Overall, 14 of 250 patients (5.6%) carried a deleterious BRCA mutation (7 BRCA1, 7 BRCA2) and 31 (12.4%) carried a variant of uncertain significance. Eight of 74 patients (10.8%) aged ≤40 years with positive FH and only 1 of 74 patients (1.4%) aged ≤40 years without FH had a mutated BRCA. Four of 75 patients (5.3%) aged 41–50 years with FH had a deleterious mutation. Only 1 of 27 patients aged >50 years at diagnosis had a BRCA mutation. All seven patients with BRCA1 mutations had grade 3 infiltrating ductal carcinoma and triple-negative breast cancer. Nine BRCA1 and 17 BRCA2 common haplotypes were observed.

Conclusion.

Prevalence of deleterious BRCA mutations is lower than expected and does not support the hypothesis that BRCA mutations alone cause the observed high percentage of breast cancer in young women of Lebanese and Arab descent. Studies to search for other genetic mutations are recommended.  相似文献   
44.
45.
The liver in alpha 1-antitrypsin deficiency   总被引:4,自引:0,他引:4  
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46.
Background and aims  Mutations in DNA mismatch repair genes are associated with high risk of digestive malignancies [hereditary non-polyposis colorectal cancer (HNPCC); Lynch syndrome]; mutations of APC and MYH are associated with classic and attenuated familial adenomatous polyposis (FAP). Although the early onset of tumors in both syndromes is characteristic of their genetic origin, pediatric malignancies remain rare. Certain reports have found familial colorectal cancer (CRC) occurring in very young patients associated with mutations in more than one gene. Materials and method  A family corresponding to the Amsterdam criteria for HNPCC, including two cases of colorectal cancer before the age of 25 years, was analyzed for mutations in the MSH2 genes by sequencing. Because polyposis was observed in a patient who developed CRC at age 16, the APC gene was also sequenced. Results  A truncating mutation in the MSH2 gene, c.258_259delTG, was carried by patients developing cancer of the colon (two patients), uterus, kidney, bladder, and/or small intestine at ages 16, 24, 43, 44, 45, and 57, respectively. A patient with CRC at age 16 was found to carry the APC c.3183_3187del5 mutation as well as the MSH2 mutation, and it is inferred that her father, deceased of CRC at age 24, was also a double heterozygote. Interpretation  These results confirm that vigilance is required when interpreting molecular results for families with very young patients, as more than one gene may contribute to the genetic risk. Cancer screening measures must also be adapted to the earlier and more penetrant risk to double heterozygotes.  相似文献   
47.
48.
Lung retention of cerium in humans.   总被引:2,自引:2,他引:0       下载免费PDF全文
A retrospective study was conducted to evaluate lung retention of particles containing cerium in subjects with and without previous occupational exposure to mineral dusts. Analytical transmission electron microscopy was performed on 459 samples of bronchoalveolar lavage (BAL) fluid and 75 samples of lung tissue. Study of the distribution of mineralogical species in human samples showed that particles containing cerium were encountered in less than 10% of subjects. The proportion of subjects with particles containing cerium in their biological samples was not different between controls and subjects with previous occupational exposure to fibrous or nonfibrous mineral dusts. This was considered as the background level of lung retention of cerium in the general population. By contrast, determination of the absolute concentration of particles containing cerium in BAL fluid and lung tissue samples showed that 1.2% (from BAL fluid) and 1.5% (from lung tissue) of subjects with previous exposure to mineral particles had high lung retention of particles containing cerium. This study is believed to be the first one in which lung retention of cerium was estimated in the general population.  相似文献   
49.
Loss of heterozygosity (LOH) was evaluated in 174 breast and ovarian tumors derived from 94 families with at least 3 first-degree relatives affected with either of these cancers. By linkage analysis 26 families were identified as having a high posterior probability of being due to BRCAI (the breadovarian cancer susceptibility locus on 17q 12–21) with lod scores varying from 0.5 1 to 9.49. Tumor genotypes were determined at at least 2 constitutionally heterozygous markers flanking BRCA I in a total of 58 tumors from these families. These tumors were derived from 52 patients, the BRCAI mutation carrier status of which was evidenced by DNA sequencing in 20, and inferred by reconstructing haplotypes in the remainder. LOH was detected in 50 (86%) tumors. and invariably involved the wild-type allele. Where informative, this allele was of paternal origin in 33 cases and of maternal origin in I0 cases. These results strongly suggest that BRCA I is a tumor suppressor gene and that LOH is greatly favored to fully inactivate it. © 1995 Wiley-Liss, Inc.  相似文献   
50.
The chemical microanalysis of chrysotile fibers obtained from human lungs and from chrysotile phagocytosed in vitro by rabbit alveolar macrophages (AM) was carried out with the use of an energy dispersive spectrometer mounted on a scanning electron microscope (SEM). This microanalysis was compared to natural fibers in order to investigate the chemical stability of chrysotile in biologic residence. The Mg versus Si content was estimated by the ratio of the peaks intensity Si:Mg. Lung samples were obtained from workmen with definite asbestos exposure, and chrysotile asbestos was extracted by chemical digestion. Phagocytosed chrysotile fibers were obtained after incubating standard chrysotile (A UICC) with rabbit alveolar macrophages for 24 hours or 5 days. Both chrysotile fibers from human lungs and from in vitro incubation with AM have shown an increase of the Si:Mg ratio in respect to standard fibers. Moreover, the results have shown that the magnesium leakage was not constant along the fiber axis and was different from one fiber to another.  相似文献   
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