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51.
SH Kleinman ; JC Niland ; SP Azen ; EA Operskalski ; LH Barbosa ; AI Chernoff ; VM Edwards ; BA Lenes ; GJ Marshall ; GJ Nemo ; et al. 《Transfusion》1989,29(7):572-580
The Transfusion Safety Study (TSS) and the National Heart, Lung, and Blood Institute (NHLBI) established a repository of approximately 200,000 sera from blood donors in late 1984 and early 1985. Collections were made in the four metropolitan areas with the highest prevalence of AIDS. Retrospective testing showed an overall anti-HIV-1 prevalence of 16 cases per 10,000 donations. In this study, the predictive value of a negative initial enzyme-linked immunoassay was estimated from both quality control specimens and the rescreening of 13,461 sera to be greater than 99.99 percent with respect to technical error. Among anti-HIV-1-positive persons, there was a 1.3- to 1.5-fold excess of first-time donors. The anti-HIV-1 prevalence among donors showed that infection was more common among young men than suggested by national reporting of AIDS cases. Anti-HIV-1 prevalence varied among the four metropolitan areas less than did reported AIDS cases, but, by 1987, the differences in the latter had decreased. Anti-HIV-1 prevalence in collection areas outside of the four major cities differed much more widely than that among the cities themselves. The TSS/NHLBI Donor Repository will remain available for the indefinite future for further evaluation of screening procedures for HIV-1 and other viruses for which transfusion is found to be an important route of transmission. 相似文献
52.
Wayne S; Der Kaloustian VM; Schloss M; Polomeno R; Scott DA; Hejtmancik JF; Sheffield VC; Smith RJ 《Human molecular genetics》1996,5(10):1689-1692
The Usher syndromes (USH) are a group of autosomal recessive diseases
characterized by progressive pigmentary retinopathy and sensorineural
hearing loss. Five USH genes have been mapped and at least one additional
gene is known to exist. By homozygosity mapping in a consanguineous family,
a sixth USH gene has been localized. Clinical findings in the four affected
children are consistent with established diagnostic criteria for Ush1.
Linkage to known USH loci was excluded, and using two genomic DNA pools,
one from the affected children and the other from the parents, 161
polymorphic markers evenly spaced across the autosomal human genome were
screened. The location of the Ush1D gene was defined by the only region
showing homozygosity by descent in the affected siblings, a 15 cM interval
on chromosome 10q bounded by D10S529 and D10S573.
相似文献
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55.
The effect of chymopapain and contrast media in the epidural space on meninges has not been studied conclusively. The authors injected chymopapain into the epidural space of monkeys and measured the degree of arachnoid fibrosis that resulted. Animals were given injections of 1.2 mL of diatrizoate (280 mg iodine per milliliter), chymopapain (100 IU/mL), kaolin (100 mg/mL) (as a positive control), or saline (0.9%) (as a negative control). Three months later the animals were killed; the dural sac was removed intact and was fixed, sectioned, stained, and examined with light microscopy. Kaolin-treated animals developed mild to marked fibrosis of the dura. The saline- and diatrizoate-treated animals developed little or no evidence of fibrosis. One of four chymopapain-treated animals developed degenerative changes in dorsal nerve roots and fibrosis in the adjacent arachnoid. The other chymopapain-treated animals had little or no evidence of fibrosis. The studies suggest that neither diatrizoate nor chymopapain causes arachnoid fibrosis. 相似文献
56.
Incubation of human mononuclear leukocytes (MNL) with human stroma-free hemolysate (SFH), purified adult hemoglobin Ao (HbAo), and oxidized HbAo (METHb) caused MNL to release compounds into the supernate that mediated neutrophil (polymorphonuclear leukocytes, PMN) chemotaxis and PMN adherence to human umbilical vein endothelial cells (HUVEC). Chemotaxis and PMN adherence to HUVEC were reduced significantly when supernates were preincubated with neutralizing antibodies to interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha), respectively, suggesting that IL-8 and TNF-alpha played significant roles in mediating these activities. Greatest chemotactic activity was observed in supernates of MNL treated with HbAo; while greatest PMN/endothelial cell (EC) adherence activity was observed in supernates of MNL treated with METHb. Furthermore, PMN/EC adherence activity was a function of METHb content in each hemoglobin solution. PMN chemotaxis, PMN adherence to HUVEC, and cytokine release increased as a function of increasing incubation time. Chemotactic activity was detected in HbAo- treated and METHb-treated MNL supernates after incubation for 6 hours and was maximal by 10 hours. IL-8 was detected in both HbAo and METHb- MNL supernates by 4 hours. PMN/EC adherence activity was detected in HbAo-MNL supernates at 10 hours and in METHb-MNL supernates at 4 hours. TNF-alpha was detected in METHb and HbAo-MNL supernates at 4 and 12 hours, respectively. These results suggest that hemoglobin solutions stimulate MNL to release IL-8 and TNF-alpha in quantities sufficient to induce PMN chemotaxis and PMN adherence to HUVEC. This is a US government work. There are no restrictions on its use. 相似文献
57.
Sintnicolaas K; van Marwijk Kooij M; van Prooijen HC; van Dijk BA; van Putten WL; Claas FH; Novotny VM; Brand A 《Blood》1995,85(3):824-828
We studied the value of leukocyte depletion of platelet transfusions for the prevention of secondary human leukocyte antigen (HLA)- alloimmunization in patients with a high-risk of prior immunization induced by pregnancies. Seventy-five female patients with hematologic malignancies (mostly acute leukemia) and a history of pregnancy were randomized to receive either standard random single-donor platelet transfusions (mean leukocytes, 430 x 10(6) per transfusion) or leukocyte-depleted random single-donor platelet transfusions. Leukocyte depletion to less than 5 x 10(6) leukocytes per platelet transfusion (mean leukocytes, 2 x 10(6) per transfusion) was achieved by filtration. Of the 62 evaluable patients, refractoriness to random donor platelets occurred in 41% (14 of 34) of the patients in the standard group and in 29% (8 of 28) of the patients in the filtered group (P = .52); anti-HLA antibodies developed in 43% (9 of 21) of individuals in the standard group and 44% (11 of 25) of cases in the filtered group. The time toward refractoriness and development of anti- HLA antibodies was similar for both groups. We conclude that leukocyte depletion of random single-donor platelet products to less than 5 x 10(6) per transfusion does not reduce the incidence of refractoriness to random donor platelet transfusion because of boostering of anti-HLA antibodies. 相似文献
58.
The incidence and consequences of HLA and non-HLA immunization were evaluated in 229 patients with aplastic thrombocytopenia. All patients were transfused with prestorage filtered red blood cells and platelets. On admission, 29 patients presented with HLA antibodies due to prior immunization by pregnancy and/or blood transfusions. Of the 200 patients showing no detectable HLA antibodies on admission, 164 could be evaluated. HLA antibodies developed in 2.7% (3 of 112) of the patients with a negative risk history of prior immunization. The occurrence of HLA antibodies in patients with a history of previous pregnancies or prior non-leukocyte-depleted blood transfusions (risk history positive) was 31% (16 of 52). Of the total of 48 patients who were or became alloimmunized, 92% (44 of 48) had a positive risk history. Ten patients with broad multispecific HLA antibodies with a panel reactivity (PRA) of greater than 70% required transfusions with HLA-matched platelets. Patients with HLA antibodies with lower PRA could be supported by random donor platelets. Two patients developed platelet-specific antibodies, causing transfusion refractoriness that necessitated selecting platelets by the absence of a platelet-specific antigen. Using prestorage leukocyte depletion of red cells and platelets with less than 5 x 10(6) residual leukocytes, 95% of the patients, including patients with a previous risk history or with HLA antibodies with low PRA, can be supported with random donor transfusions for the entire duration of their thrombocytopenic periods. 相似文献
59.
Prognostic implications of cytogenetic studies in an intensively treated group of children with acute lymphoblastic leukemia 总被引:2,自引:0,他引:2
Fletcher JA; Kimball VM; Lynch E; Donnelly M; Pavelka K; Gelber RD; Tantravahi R; Sallan SE 《Blood》1989,74(6):2130-2135
We assessed the prognostic significance of leukemia cell cytogenetics by analyzing bone marrow aspirates obtained at time of diagnosis in 165 children on a single protocol for acute lymphoblastic leukemia (ALL). These children were assigned to six mutually exclusive cytogenetic categories as follows: (1) hyperdiploid, with 50 or more chromosomes (n = 35); (2) hyperdiploid, with 47 to 49 chromosomes (n = 11); (3) diploid (n = 42); (4) pseudodiploid (n = 34); (5) hypodiploid (n = 9); and (6) insufficient data (n = 34). At a median follow-up of 5 years, there were no statistically significant differences between any of these cytogenetic categories in either event-free or overall survival. Those children with chromosomal translocations (n = 26) appeared to fare the same as those lacking translocations (n = 105). The absence of karyotypic prognostic significance was observed not only within the overall group, but also when the results were stratified by standard- risk and high-risk status. Of the specific structural chromosome changes that we studied, only the Philadelphia chromosome (Ph) appeared to confer a poor prognosis, although there were too few such cases to achieve statistical significance. Although we did not detect the event- free survival differences that have been described previously in hyperdiploid, hypodiploid, and pseudodiploid childhood ALL, our findings must be viewed as preliminary given the small number of children in some of the cytogenetic categories. We think that the prognostic implications of these cytogenetic features might have been nullified by improvements in therapy. 相似文献
60.
CD4 and CD8 T lymphocyte subsets, the late T cell activation marker,
HLA-DR, and serum interleukin-6 (IL-6) levels of 57 polymyalgia rheumatica
(PMR) patients were followed over 2 yr to investigate whether they could be
used to predict the safe withdrawal of steroid therapy. Cell phenotypes
were studied by flow cytometry and IL-6 levels by ELISA. %CD8 cells were
reduced below the normal range in PMR patients prior to steroid therapy. In
56% of patients, the %CD8 T lymphocytes failed to return to normal levels
when quiescent disease allowed cessation of steroid therapy. Activated CD8
T cells, as detected by HLA-DR positivity, were above the normal range at
the initiation of therapy and showed a negative correlation with %CD8 T
cells. The serum concentration of IL-6 fluctuated over 24 months, and the
correlation between IL-6 and erythrocyte sedimentation rate (ESR) seen
prior to treatment was not seen at later intervals. The %CD8 T cell and
serum IL-6 levels are not a good indicator of disease activity in PMR and
are, therefore, unable to predict the safe withdrawal of steroids.
相似文献