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91.
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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
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95.
T. Hase D. R. Dubois P. L. Summers M. B. Downs M. A. Ussery 《Archives of virology》1993,130(1-2):131-143
Summary The replication rates and pathogenicities of the SA 14 parent and SA 14-14-2 vaccine strains of Japanese encephalitis (JE) virus in neurons of the mouse brain following intracerebral inoculation were compared. All the mice inoculated with the SA 14 parent strain died within one week postinoculation (p.i.), whereas all the mice inoculated with the SA 14-14-2 vaccine strains survived without showing any signs of central nervous system (CNS) involvement. The virus titers of the mouse brains inoculated with the SA 14 strain reached progressively higher levels until day 5 when the animals died. On the other hand, the virus titers of the mouse brains inoculated with the SA 14-14-2 strain persisted at low levels for several days and could not be detected after 10 days. In the routine electron microscopical study, a majority of neurons in the mouse brains inoculated with the SA 14 strain contained virions and showed characteristic cytopathological changes in connection with viral replication. In the brains inoculated with the SA 14-14-2 strain, however, we failed to find neurons containing virions or showing characteristic cytopathological changes. In the alkaline phosphatase immunostaining of paraffin-embedded sections, a majority of neurons in the brains of mice inoculated with the SA 14 strain stained positively on day 5 p.i., but only a small number of neurons in scattered small foci stained positively in the brains inoculated with the SA 14-14-2 strain. The immunogold staining of Vibratome sections also revealed the identical patterns; moreover, electron microscopical examination of the immunopositive foci of the brain inoculated with the vaccine strain revealed neurons that contained virions in dilated cisternae of rough endoplasmic reticulum (RER), indicating that the SA 14-14-2 strain also replicated, albeit poorly, in neurons. The present results showed that upon intracerebral inoculation into mice the SA 14 parent strain of JE virus grew vigorously in a large number of neurons, killing the animals, while the SA 14-14-2 vaccine strain grew poorly only in a small number of neurons without causing mortality. Possible mechanisms involved in the alteration of pathogenicity between the SA 14 parent virus and the SA 14-14-2 vaccine virus are discussed. 相似文献
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97.
Benign prostatic hypertrophy: retrograde transurethral dilation of the prostatic urethra in humans. Work in progress 总被引:1,自引:0,他引:1
Castaneda F; Reddy P; Wasserman N; Hulbert J; Lund G; Letourneau JG; Hunter DW; Castaneda-Zuniga WR; Amplatz K 《Radiology》1987,163(3):649-653
Retrograde transurethral balloon dilation of the prostatic urethra was performed in five human volunteers with benign prostatic hypertrophy. Each patient underwent cystoscopy, uroflow studies, voiding cystourethrography, retrograde urethrography, and magnetic resonance imaging before dilation and at defined intervals afterward. The longest follow-up to date is 8 months. Patients were given topical anesthetics and mild sedatives, and dilation was performed with a 25-mm urethroplasty balloon catheter inflated at 3-6 atm for 10 minutes. All catheter manipulations were done with a guide wire and under fluoroscopic control. Significant resolution of symptoms of prostatism was seen in four patients. The unsatisfactory results in the last patient were believed to be caused by ineffectual dilation of predominantly middle lobe hypertrophy--a condition that is now regarded as a contraindication to dilation. This technique has promise to replace transurethral resection of the prostate as the treatment of choice for this common male ailment. 相似文献
98.
Between January and March 1986, 117 wives of insulation workers exposed to asbestos were screened by means of chest radiography, pulmonary function testing, and a detailed questionnaire. The final study group included 93 women over 40 years of age. Eighteen of these (19.4%) demonstrated pleural changes consistent with asbestos exposure, including pleural plaque (88.9%), diaphragm plaque (27.8%), pleural calcification (16.6%), and diffuse pleural thickening (5.5%). In statistical correlation between the groups with normal and abnormal radiographs, the only factor that proved significant was the year of first exposure (the duration of the latent period). Finally, radiographs of the husbands were compared for 17 of the 18 wives with radiographic abnormalities. Fourteen of the husbands (82%) demonstrated more severe radiographic changes than their wives. 相似文献
99.
Recovery of human immunodeficiency virus from ocular tissues in patients with acquired immune deficiency syndrome 总被引:4,自引:0,他引:4
Human immunodeficiency virus (HIV) was recovered from multiple ocular tissues in three patients with acquired immune deficiency syndrome (AIDS). Consistently found in the retina, HIV was also detected in the conjunctiva, cornea, and iris. In two cases, HIV was detectable despite treatment with oral zidovudine. All three patients had bilateral cytomegalovirus (CMV) retinitis managed by intravitreal injection of ganciclovir. Culture of the retina for CMV was negative in all three cases. The finding of HIV in multiple ocular tissues is consistent with the neurotropic nature of the virus, and may explain some of the common ocular manifestations of AIDS such as AIDS retinopathy. Infection with HIV may predispose the retina to other opportunistic infections and may explain the high incidence of CMV retinitis in AIDS patients. This is the first report of HIV isolation from tissue within the eye. 相似文献
100.
A new guide wire that provides markedly improved torque control is described. It was compared with a conventional guide wire in two models, one simulating a drainage tube with numerous side holes and one, the biliary tree. The new wire was much more easily controlled than the conventional guide wire and passed through both models significantly faster (P less than .01 and P less than .005). Although some deterioration in control was noted when it was inserted through a catheter in vivo, the new torque-control wire still exhibited a definite improvement over conventional wires in directional control. 相似文献