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11.
A frame-shift 9254del5 mutation was independently identified in 12 families, eleven of them with Spanish ancestors, in a BRCA2 screening performed in 841 breast and/or ovarian cancer families and in 339 women with breast cancer diagnosed before the age of 40 at different centers in France and Spain. We sought to analyze in detail the haplotype and founder effects of the 9254del5 and to estimate the time of origin of the mutation. Eight polymorphic microsatellite markers and two BRCA2 polymorphisms were used for the haplotype analyses. The markers were located flanking the BRCA2 gene spanning a region of 6.1 cM. Our results suggest that these families shared a common ancestry with BRCA2 9254del5, which is a founder mutation originating in the Northeast Spanish, with an estimated age of 92 (95% CI 56-141) generations.  相似文献   
12.
Despite well-established histopathological features and the development of immunostaining of human neoplasms, there are a number of cases in which surgical pathologists cannot assure the origin of synchronous and metachronous tumors. In many cases, the classification of these lesions as either two separate primary tumors or as a single primary tumor with a metastasis has significant implications with respect to patient prognosis and recommendations for therapy. To establish the origin of tumors, we assessed tumor cell clonality using PCR-based microsatellite analysis on microdissected archival tissues for loss of heterozygosity (LOH) and microsatellite instability (MSI) in a series of 19 paired synchronous and metachronous tumors from several organs. As a control group, 15 autopsy cases with an unequivocally recognizable primary tumor and associated metastases were also examined. Based on LOH and MSI findings, and using a panel of 4 to 12 (median 7) microsatellite markers, we were able to establish the clonal pattern of microsatellite changes in 17 out of 19 (89%) biopsy cases and thus determine if they were either double primary tumors (41%) or metastases (59%). Of interest, identical or similar pattern of microsatellite abnormalities were detected in 15 primary tumors and corresponding metastasis from autopsies. Our results indicate that microsatellite analysis for LOH and MSI, as an expression of clonality, provides a useful tool to distinguish double primary neoplasms and metastases in synchronous and metachronous tumors.  相似文献   
13.
Cohesin component dynamics during meiotic prophase I in mammalian oocytes   总被引:7,自引:0,他引:7  
Cohesins are chromosomal proteins that form complexes involved in the maintenance of sister chromatid cohesion during division of somatic and germ cells. Three meiosis-specific cohesin subunits have been reported in mammals, REC8, STAG3 and SMC1 beta; their expression in mouse spermatocytes has also been described. Here we studied the localization of different meiotic and mitotic cohesin components during prophase I in human and murine female germ cells. In normal and atretic human fetal oocytes, from leptotene to diplotene stages, REC8 and STAG3 colocalize in fibers. In murine oocytes, SMC1beta, SMC3 and STAG3 are localized along fibers that correspond first to the chromosome axis and then to the synaptonemal complex in pachytene. Mitotic cohesin subunit RAD21 is also found in fibers that decorate the SC during prophase I in mouse oocytes, suggesting a role for this cohesin in mammalian sister chromatid cohesion in female meiosis. We observed that, unlike human oocytes, murine synaptonemal complex protein SYCP3 localizes to nucleoli throughout prophase I stages, and centromeres cluster in discrete locations from leptotene to dictyate. At difference from meiosis in male mice, the cohesin axis is progressively lost during the first week after birth in females with a parallel destruction of the axial elements at dictyate arrest, demonstrating sexual dimorphism in sister chromatid cohesion in meiosis.  相似文献   
14.
Leukocyte migration across vascular endothelium is mediated by chemokines that are either synthesized by the endothelium or transferred across the endothelium from the tissue. The mechanism of transfer of two chemokines, CXCL10 (interferon gamma-inducible protein [IP]-10) and CCL2 (macrophage chemotactic protein [MCP]-1), was compared across dermal and lung microvessel endothelium and saphenous vein endothelium. The rate of transfer depended on both the type of endothelium and the chemokine. The permeability coefficient (Pe) for CCL2 movement across saphenous vein was twice the value for dermal endothelium and four times that for lung endothelium. In contrast, the Pe value for CXCL10 was lower for saphenous vein endothelium than the other endothelia. The differences in transfer rate between endothelia was not related to variation in paracellular permeability using a paracellular tracer, inulin, and immunoelectron microscopy showed that CXCL10 was transferred from the basal membrane in a vesicular compartment, before distribution to the apical membrane. Although all three endothelia expressed high levels of the receptor for CXCL10 (CXCR3), the transfer was not readily saturable and did not appear to be receptor dependent. After 30 min, the chemokine started to be reinternalized from the apical membrane in clathrin-coated vesicles. The data suggest a model for chemokine transcytosis, with a separate pathway for clearance of the apical surface.  相似文献   
15.
Gene therapy of cancer based on interleukin 12   总被引:3,自引:0,他引:3  
Tumor formation and growth depends mainly on the inability of the organism to elicit a potent immune response, and on the formation of new blood vessels that enable tumor nutrition. Interleukin-12 (IL-12) therapy can target both processes. And IL-12-based gene therapy may restrict IL-12 production to the relevant site in order to obtain enhanced antitumor activity and reduced toxicity. In the clinical setting, IL-12 gene transfer can be used either to improve the pharmacokinetic/pharmacodynamic profile of the cytokine, to transduce dendritic cells or to enhance the efficiency of antitumor vaccination. It can also synergize with other procedures involving the simultaneous transfer of other transgenes or non-gene based strategies. The strong anti-tumoral power shown in many different animal models has not been found in early clinical trials in which cancer patients were treated by peritumoral injections of autologous fibroblasts producing IL-12, intratumoral injections of an adenoviral vector encoding human IL-12 genes, or intratumoral injection of autologous dendritic cells transduced ex vivo with this same adenoviral vector. However, these trials have set the proof-of-concept that local production of IL-12 inside a tumor can stimulate tumor infiltration by effector immune cells and that in some cases it is followed by tumor regression. From the many questions that arise after these disappointing results the most relevant concerns the duration and intensity of transgene expression and the capability to monitor this topics in vivo. New vectors that might achieve regulated, long-term production of this cytokine might have better results and merit clinical testing.  相似文献   
16.
BACKGROUND: The most serious limitation of the serodiagnosis of parasitoses is the occurrence of cross-reactions. OBJECTIVE: The possible use of Anisakis simplex major allergen Ani s 1 for diagnosis. PATIENTS AND METHODS: Forty-nine non-fish-allergic patients with Anisakis simplex hypersensitivity, 21 patients without allergic episodes suffering intestinal anisakiasis with obstruction of the intestinal lumen, and 10 unrelated sera as a control were included in this study to determine specific immunoglobulin (Ig)E and IgG to Anisakis simplex major allergen Ani s 1 by immunoblotting. RESULTS: Eighty-six percent of patients with Anisakis simplex hypersensitivity showed specific IgE directed to Ani s 1. Identical result was obtained for IgG detection in this group. Among patients with intestinal anisakiasis, 86% showed specific IgE, but only 29% had specific IgG (P < 0.001, two-tailed Fisher exact test). One of the 10 control subjects was positive both for IgE and IgG (P < 0.001). CONCLUSIONS: Determination of specific IgE directed to Anisakis simplex major allergen Ani s 1 is a useful tool for the diagnosis of hypersensitivity and intestinal anisakiasis. Further, measurement of specific IgG directed to Anisakis simplex major allergen Ani s 1 is only valid for Anisakis simplex allergy.  相似文献   
17.
Permanent tolerance to allografts can be induced in adult rats by donor-specific transfusions (DST) prior to transplantation. We have previously reported, in a model of heart allograft, the presence of a heavy leukocyte infiltrate, in the allograft which displayed a strong allospecific cytotoxicity when tested in vitro against donor cells, and a strong accumulation of mRNA for granzyme A and perforin in vivo. In contrast, there was a major decrease in the accumulation of mRNA for interleukin-2 and interferon-γ. These results suggested that the DST-induced tolerance was associated with a decrease in type-1 T helper (Th1) cell function. The major role of preformed antibodies in xeno and allorejection is clearly established. Nevertheless, the consequences of alloantibody production in acute rejection and tolerance induction remains to be elucidated. We here analyze the alloantibody response in rejecting and DST-treated recipients. We show that, after transplantation, tolerant recipients, in contrast to rejecting ones, mount a low IgM alloresponse that switches to low IgG production. Detailed analysis of IgG alloantibodies in DST-treated recipients revealed that their production decrease was not equally distributed. Whereas rejecting animals mounted a strong anti-class I and II IgG alloantibody response, DST-treated recipients produced anti-class II and low titers of anti-class I IgG alloantibodies. Furthermore, among IgG subclasses, tolerant recipients predominantly produced IgG2a, a profile which, in the rat, is compatible with a Th2-controlled response. Finally, the passive transfer of immune serum from rejecting animals to DST-treated recipients could abrogate the tolerance. We suggest that the absence of anti-class I alloantibodies combined with preserved and/or increased anti-class II production plays a major role in graft tolerance in this model. These results reinforced the role of alloantibodies in rejection and in induction of tolerance.  相似文献   
18.
19.
Background/PurposeThis study aimed to compare preoperative management strategies for patients undergoing trephination for pilonidal disease and evaluate risk factors for recurrence.MethodsA retrospective review was performed of children undergoing index surgical treatment with trephination for pilonidal disease between September 2017 and April 2019. Intraoperative and postoperative management were standardized. Demographic and perioperative data were collected and analyzed.ResultsOne-hundred twenty patients were identified with a median follow-up time of 7.5 months (interquartile range 4.1–13.2 months). Overall, 24 (20%) patients had a postoperative recurrence of pilonidal disease. Patients with multiple preoperative surgery clinic visits were less likely to have recurrent disease compared to those seen only once preoperatively (11% vs 26%, p = 0.040). Compared to patients without recurrence, those who recurred went to the operating room sooner from the time of initial surgical consultation (32 days vs 54 days, p < 0.001). Perioperative antibiotics, history of acute infection, and prior drainage procedures were not risk factors for recurrence.ConclusionsMultiple preoperative clinic visits are associated with a lower recurrence rate in children undergoing trephination for pilonidal disease. An increased duration of preoperative medical management may be responsible for this finding. Prospective study is needed to confirm these findings and identify additional factors that influence recurrence.Type of StudyTreatment Study.Level of EvidenceIII (Retrospective Comparative).  相似文献   
20.
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