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61.
LMP-1, an Epstein-Barr viral (EBV) latency protein, is considered a viral oncogene because of its ability to transform rodent fibroblasts in vivo and render them tumorigenic in nude mice. In human B cells, EBV LMP-1 induces DNA synthesis and abrogates apoptosis. LMP-1 is expressed in EBV-transformed lymphoblastoid cell lines, nasopharyngeal carcinoma (NPC), a subset of Hodgkin's disease (HD), and in EBV-associated lymphoproliferative disorders (EBV-LPDs). Recently, focused deletions near the 3' end of the LMP-1 gene (del-LMP-1, amino acids 346-355), in a region functionally related to the half-life to the LMP-1 protein, have been reported frequently in human immunodeficiency virus (HIV)- associated HD (100%) and EBV+ Malaysian and Danish peripheral T-cell lymphomas (100%, 61% respectively), but less frequently in cases of HD not associated with HIV (28%, 33%) and infectious mononucleosis (33%). To further investigate the potential relationship of del-LMP-1 to EBV- LPDs associated with immunosuppression or immunodeficiency, we studied 39 EBV-associated lymphoproliferations (10 benign, 29 malignant) from four distinct clinical settings: posttransplant (4 malignant, 1 reactive); HIV+ (18 malignant, 2 reactive); nonimmunodeficiency malignant lymphoma (ML) (7 cases); and sporadic EBV infection with lymphoid hyperplasia (7 cases). The presence of EBV within lymphoid cells was confirmed by EBV EBER1 RNA in situ hybridization or by polymerase chain reaction (PCR) analysis. EBV strain type and LMP-1 deletion status were determined by PCR. EBV strain types segregated into two distinct distributions: HIV+ (9 A; 11 B) and non-HIV (19 A, 0 B), consistent with previous reports. Overall, del-LMP-1 were found in 1 of 5 (20%) Burkitt lymphomas (BL); 17 of 24 (71%) aggressive non- Hodgkin's lymphoma (agg-NHL), and 2 of 10 (20%) reactive lymphoid proliferations. Of the agg-NHLs, del-LMP-1 were present in 4 of 4 PT-ML (100%); 10 of 15 HIV+ ML (67%); and 3 of 5 nonimmunodeficiency malignant lymphoma (ML, 60%). A total of 2 of 7 (28%) sporadic EBV- associated lymphoid hyperplasias contained a del-LMP-1. All del-LMP-1 were identical by DNA sequence analysis. No correlation was identified between the presence of del-LMP-1 and the EBV strain type observed. The high incidence of del-LMP-1 observed in agg-NHLs (71%), in contrast to the relatively low incidence observed in reactive lymphoid proliferations (28%), suggests that the deleted form may be preferentially selected in lymphomatous processes. All posttransplant agg-NHLs contained a del-LMP-1, and a similar frequency of del-LMP-1 was observed in both HIV-associated ML (66%) and nonimmunodeficiency ML (60%), suggesting that impairment of immune function alone is not a requirement for the expansion of malignant cells infected by EBV stains containing the deleted LMP-1 gene. 相似文献
62.
63.
J N Barendregt G P Beyer J L Coenegrachts R Slotema J Roos 《Annales de médecine interne》1986,137(7):565-567
A patient is described who showed signs of eclampsia in the 31st week of first pregnancy. The cause of shock proved to be a subcapsular hematoma in the liver and it was accompanied by a hematothorax. The diagnosis was made by CT-scanning. The pathogenesis is discussed. 相似文献
64.
65.
The acrosome reaction is an important marker for human sperm function.
Since different laboratory techniques may be used for the detection of this
exocytotic process, the purpose of the present study was to compare three
common markers [Pisum sativum agglutinin (PSA), concanavalin A (ConA),
double staining] and transmission electron microscopy for identification of
acrosomal changes. Preliminary findings had demonstrated that similar
results were achieved with Trypan Blue and Hoechst 33258 staining.
Therefore, supravital stainings were omitted. In various experiments, human
spermatozoa were treated with two concentrations (10 and 3.3 microM) of
calcium ionophore A23187 for 15, 30 and 60 min after capacitation for 3 and
6 h at 37 degrees C. The percentages of spermatozoa with acrosomal loss
detected by fluorescein isothiocyanate (FITC)-ConA were consistently lower
than those obtained by double staining or FITC-PSA, which showed comparable
results. Following 6 h of capacitation and incubation with 10 microM
ionophore for 1 h at 37 degrees C, 25.9 +/- 15.7% of all spermatozoa showed
almost complete loss of the acrosomal content. Binding of FITC- ConA to the
acrosomal region was observed in 27.0 +/- 13.2% of spermatozoa obtained
from the same sample. FITC-ConA and double staining or FITC-PSA detect
different stages of the acrosome reaction and may be helpful for a
differentiated evaluation of this sperm function.
相似文献
66.
67.
An analysis of autopsy findings in 68 patients who died with vascular surgical disorders was performed. Incorrect diagnoses and therapy were evaluated. It was found that complications of the primary disease or its treatment were frequently missed clinically (41%). Septic complications and severe hemorrhage were common in examinations of morbidity and mortality. In 13% of cases a treatment error with adverse impact on survival was detected. It is concluded that postmortem examination is a valuable tool in the final evaluation of patient care in a vascular surgical unit. A repeated plea for the autopsy is supported by this study. 相似文献
68.
69.
Epstein DM; Stephenson LW; Gefter WB; van der Voorde F; Aronchik JM; Miller WT 《Radiology》1986,161(2):423-427
Practicing thoracic surgeons were randomly surveyed to evaluate how computed tomography (CT) has influenced the preoperative evaluation of bronchogenic carcinoma. Thirty-six percent of the 529 respondents routinely requested CT and 62% did so selectively. Approximately 40% indicated that CT provided useful information in most cases. Nearly all surgeons (98.7%) do not rely on the identification of enlarged lymph nodes with CT to spare the patient surgical staging; however, 77.5% are influenced by CT results in their staging procedures. Fifty-seven percent reported that a negative CT study eliminates surgical staging entirely unless the patient has a "coin lesion," in which case 75% are willing to proceed directly to thoracotomy. For surgeons who use CT selectively, an abnormal mediastinal contour on the radiograph was the most frequent radiologic abnormality to prompt CT (85%). Thirty-seven percent are influenced by tumor histology in their decision to request CT. There was little difference in the pattern of CT use between university and community hospital surgeons. 相似文献
70.
J. J. Barendregt L. Bonneux P. J. Van der Maas 《Bulletin of the World Health Organization》1996,74(4):439-443
In studies for the 1993 World development report: investing in health Murray et al. developed the disability-adjusted life year (DALY). This article examines one particular aspect of the DALY methodology: the weighting of life years by age. For the quantitative implementation of this notion Murray proposed a general equation to weight life years by age, which specifies that the years lived between the ages of 9 and 54 years have a weight greater than unity, and for the years outside this range less than unity. The age-weighted life years are used to calculate the "expected years of life lost" (EYLL). Comparison of age-weighted and unweighted age-specific life expectancies shows that the age range which becomes more important due to weighting is not 9-54 years, but 0-27 years. This happens because the EYLL is an age-weighting system in itself, emphasizing the young. The result of piling one age-weighting system on top of the other gives an even stronger emphasis on the young than the EYLL generates by itself. Although this is unlikely to upset the results from the Global Burden of Disease study, we do not think it is desirable. And it is certainly different from what we were led to expect. 相似文献