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51.
Antibody to donor HLA antigens is a significant barrier to both access to and outcome of allogeneic transplants. Many attempts have been made to desensitize patients with HLA-specific antibody, but the most effective and durable have been treatment with high-dose pooled human intravenous immunoglobulin (IVIg) and a combination of plasmapheresis and low-dose IVIg. Despite the success of these treatments, low levels of donor-specific antibody (DSA) persist in some patients. We examined factors that may be related to and used to predict the elimination of DSA. The most significant associations have been strength of antibody at initiation of treatment and antibody specificity, although other factors revealed a trend toward association. We demonstrate how the types of data generated here can be used to predict elimination or persistence of DSA. 相似文献
52.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
53.
Telomere lengths of translocation-associated and nontranslocation-associated sarcomas differ dramatically 下载免费PDF全文
Montgomery E Argani P Hicks JL DeMarzo AM Meeker AK 《The American journal of pathology》2004,164(5):1523-1529
Sarcomas can be divided into those with specific translocations displaying monotonous cytomorphology, and those with complex karyotypes and marked cellular pleomorphism. Telomeres contain terminal DNA sequence repeats that maintain chromosomal stability. Telomeres shorten with cell division and may become dysfunctional leading to chromosomal instability. Using a fluorescence in situ hybridization/immunofluorescence method to assess telomere lengths in archival tissues we analyzed these two types of sarcomas using paraffin-embedded primary tumor specimens. Tissues from nine sarcomas with characteristic translocations (two synovial sarcomas, two alveolar rhabdomyosarcomas, two desmoplastic round cell tumors, and one each of infantile fibrosarcoma, myxoid liposarcoma, cellular congenital mesoblastic nephroma) and nine without (four malignant fibrous histiocytomas, two leiomyosarcomas, one pleomorphic rhabdomyosarcoma, one dedifferentiated chondrosarcoma, and one malignant peripheral nerve sheath tumor) were analyzed. In all (nine of nine) cases with specific translocations, which generally have few karyotypic abnormalities, telomere lengths were similar to or reduced compared to surrounding nonneoplastic tissues. In contrast, telomeres in cases lacking specific translocations, which generally contain complex karyotypes, were often found to be dramatically lengthened and heterogeneous. In addition to markedly elongated telomeres, seven of nine (78%) complex cases exhibited large brightly stained regions corresponding to a specific type of promyelocytic leukemia nuclear body found in immortalized cells that maintain telomeres in a telomerase-independent manner [alternative lengthening of telomeres (ALT) pathway]. This phenotype is unlike that of epithelial neoplasms that typically display complex karyotypes with abnormally short telomeres maintained by the enzyme telomerase. The discovery of heterogeneous telomere lengths and evidence of the ALT pathway in the majority of sarcomas with complex karyotypes supports the existence of a telomere maintenance pathway incapable of full karyotypic stabilization in pleomorphic sarcomas. These findings provide additional molecular-genetic evidence supporting the dichotomous grouping of sarcomas into those with characteristic signature translocations without extensive additional karyotypic abnormalities, and those without such signature translocations that typically display very complex karyotypes, and point to telomere dysfunction as a plausible contributor to the chromosomal aberrations found in complex sarcomas. 相似文献
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Glasson EJ Sullivan SG Hussain R Petterson BA Montgomery PD Bittles AH 《Clinical genetics》2002,62(5):390-393
Cohort studies have indicated that the survival of individuals with Down's syndrome has dramatically increased over the past 50 years. Early childhood survival in particular has shown major improvement, due largely to advances in cardiac surgery and in general health management. The present study was based on a continuous cohort of 1332 people with Down's syndrome in Western Australia, registered for intellectual disability services between 1953 and 2000. Their life expectancy was 58.6 years, 25% lived to 62.9 years, and the oldest living person is 73 years of age. Life expectancy for males was greater than females by 3.3 years. The substantial increase in survival across the study period means that the life expectancy of people with Down's syndrome is approaching that of the general population, but accompanied by a range of significant mid-life health problems. The findings are of relevance to all developed countries and have considerable implications in terms of the counselling information provided to families at risk of having a child with Down's syndrome. 相似文献
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Acute hypothalamic-pituitary-adrenal responses to the stress of treadmill exercise. Physiologic adaptations to physical training 总被引:8,自引:0,他引:8
A Luger P A Deuster S B Kyle W T Gallucci L C Montgomery P W Gold D L Loriaux G P Chrousos 《The New England journal of medicine》1987,316(21):1309-1315
To study the effects of physical conditioning on the hypothalamic-pituitary-adrenal axis, we examined the plasma ACTH, cortisol, and lactate responses in sedentary subjects, moderately trained runners, and highly trained runners to graded levels of treadmill exercise (50, 70, and 90 percent of maximal oxygen uptake) and to intravenous ovine corticotropin-releasing hormone (1 microgram per kilogram of body weight). Basal evening concentrations of ACTH and cortisol, but not of lactate, were elevated in highly trained runners as compared with sedentary subjects and moderately trained runners. Exercise-stimulated ACTH, cortisol, and lactate responses were similar in all groups and were proportional to the exercise intensity employed. These responses, however, were attenuated in the trained subjects when plotted against applied absolute workload. Only the highly trained group had diminished responses of ACTH and cortisol to ovine corticotropin-releasing hormone, consistent with sustained hypercortisolism. We conclude that physical conditioning is associated with a reduction in pituitary-adrenal activation in response to a given workload. Alterations of the hypothalamic-pituitary-adrenal axis consistent with mild hypercortisolism and similar to findings in depression and anorexia nervosa were found only in highly trained runners. Whether these alterations represent an adaptive change to the daily stress of strenuous exercise or a marker of a specific personality profile in highly trained athletes is unknown. 相似文献
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