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41.
Epstein-Barr virus gene expression and epithelial cell differentiation in oral hairy leukoplakia. 下载免费PDF全文
J. A. Thomas D. H. Felix D. Wray J. C. Southam H. A. Cubie D. H. Crawford 《The American journal of pathology》1991,139(6):1369-1380
Hairy leukoplakia (HL) is an Epstein-Barr (EB) virus related lesion of oral mucosa that is principally associated with human immunodeficiency virus-induced immunosuppression. To understand the nature of EB virus involvement in these lesions, this study compares the distribution of EB virus DNA and EB viral gene products with the pattern of keratinocyte differentiation in 12 lateral tongue biopsies of HL. Evidence of replicating EB viral infection and abundant virus production was demonstrated in the superficial epithelium of most (92%) samples by means of in situ hybridization and immunocytochemical techniques. Epstein-Barr virus latent membrane protein also was identified in 45% of samples, suggesting that this viral gene product, which is usually associated with EB virus latent infection, may be transiently expressed during viral replication in HL epithelium. The absence of detectable EB virus involvement in basal keratinocytes, however, fails to support the theory that latent infection occurs in basal epithelium. From this study, EB viral gene expression in HL appears to be linked with epithelial maturation. Conversely, the normal patterns of keratinocyte differentiation in these lesions do not appear to be appreciably altered by association with EB virus. 相似文献
42.
Charlotte
rndal Nils Mandahl Birgitta Carln Helena Willn Johan Wennerberg Sverre Heim Felix Mitelman 《Cancer Genetics and Cytogenetics》1992,60(2):147-151
Near-haploid solid tumors are very rare. In a storiform-pleomorphic malignant fibrous histiocytoma (MFH) of bone, we found three cell populations: one with a near-haploid, a second with a near-diploid, and a third with a near-tetraploid chromosome number. The near-haploid cells had few structural rearrangements: i(12p) and t(13q21q) in one clone, and these two and an additional t(19;?)(p11;?) in another clone. One structurally normal copy of all chromosomes was also present, except that the only chromosome 13 was involved in the t(13q21q). There were also two near-diploid clones, one without the t(19;?) and one with a single copy of this derivative chromosome. This is the first MFH reported to have a near-haploid modal chromosome number, and also the first tumor with i(12p) among bone and soft tissue tumors. 相似文献
43.
Nils Mandahl Yuesheng Jin Sverre Heim Helena Willn Johan Wennerberg Anders Birklund Felix Mitelman 《Genes, chromosomes & cancer》1990,1(4):315-316
Cytogenetic analysis of a cavernous hemangioma with transition to angiosarcoma revealed the mosaic karyotype 47, XY,+5/46, X,-Y,+5/45, X,-Y/46, XY. No cytogenetically analyzed hemangiomas or angiosarcomas have been reported before. 相似文献
44.
Gert Baumann Stephan B. Felix Claus D. Heidecke Gotthard Rieß Ursula Loher Liesel Ludwig Prof. Dr Hans Blömer 《Inflammation research》1984,15(3-4):216-228
Left ventricular infarction (AMI) was produced in experimental animals and the contractile response to -adrenergic and H2-histaminergic stimulation by isoproterenol and impromidine tested in the isolated perfused heart preparation. Adenylate cyclase activity as well as binding characteristics of [3H]-dihydroalprenolol ([3H]-DHA), [3H]-methyl-tiotidine ([3H]-TIOT) and [3H]-quinuclidinyl benzilate ([3H]-QNB) to cardiac
1-, H2- and cholinergic muscarinic receptors were determined in sarcolemmal membrane preparations of the right ventricle of the same hearts. In addition, an attempt was made to elucidate the therapeutic value of post-AMI treatment with impromidine in the presence and absence of-sympathomimetic, in contrast to administration of prenalterol and the conventional therapy with -sympathomimetic drugs, e.g. dobutamine. Three days post-AMI the dose-response curve for isoproterenol of right ventriculardP/dt
max was significantly depressed, while the inotropic effect of impromidine was not impaired. Stimulation of adenylate cyclase activity by isoproterenol was reduced by 80% whereas impromidine and NaF stimulation rates were unaltered. Receptor-binding studies indicated a 90% loss and 10-times lowered affinity (K
D) of the remaining -receptors while specific [3H]-TIOT- and [3H]-QNB-binding was unchanged.Administration of dobutamine increased mortality rates and extension of infarct size, led to a further decrease in contractile response to isoproterenol, induced complete insensitivity of adenylate cyclase to isoproterenol stimulation and caused pronounced additional reduction of number and affinity of [3H]-DHA-binding sites. In contrast, all above alterations were prevented by treatment with either prenalterol or combined administration of impromidine plus metoprolol. It is concluded, that these alterations in the non-ischemic, uninvolved myocardium post-AMI are the result of catecholamine-induced specific damage of sarcolemmal -receptors. Furthermore, treatment with H2-agonists in combination with -blocking agents may have beneficial effects, whereas conventional therapy with -sympathomimetic drugs tends to worsen the already depressed function of the -adrenergic stimulation mechanism.Supported by grants Ba 666/1 and Ba 666/2-2 from the Deutsche Forschungsgemeinschaft (DFG).Data presented in this paper are part of a doctoral thesis by Dr S.B. Felix. 相似文献
45.
46.
Relationship of polymorphisms in the renin-angiotensin system and in E-selectin of patients with early severe coronary heart disease 总被引:8,自引:0,他引:8
K. Wenzel A. Blackburn M. Ernst M. Affeldt R. Hanke G. Baumann S. B. Felix F. X. Kleber K. Rohde C. Gläser A. Speer 《Journal of molecular medicine (Berlin, Germany)》1997,75(1):57-61
Previous association studies between angiotensin-converting enzyme (ACE) and angiotensinogen (AGT) polymorphisms and several
cardiovascular diseases have reported variable results. Therefore we examined the association of the DNA variants of ACE and
AGT with early, severe coronary heart disease (CHD). In addition, we compared the genotypes of both polymorphisms and the
recently discovered polymorphism in the E-selectin gene in both patients and an unselected population. This study included
113 patients with severe CHD (50 years old or less) and up to 197 control subjects. The frequencies of the ACE I/D variants
were 48% I and 52% D in the controls and 46% I and 54% D in the patients. The frequencies of the AGT-M235T polymorphism were
60.8% M and 39.2% T in controls and 49.1% M and 50.9% T in the patients. The frequencies of the S128R polymorphism of the
E-selectin were 91.3% S and 8.7% R in controls and 84.5% S and 15.5% R in the patients. In our studies the DD genotype of
ACE was not associated with early severe CHD. We found a correlation between the M235T molecular variant of AGT and the S128R
variant of E-selectin to early severe CHD.
Received: 15 February 1996 / Accepted: 2 October 1996 相似文献
47.
48.
Recent experiments have shown that shortening and stretching of sarcomeres in single activated and unactivated myofibrils occur in stepwise fashion (Yang et al. (1998) Biophys J 74: 1473-1483; Blyakhman et al. (2001) Biophys J 81: 1093-1100; Yakovenko et al. (2002) Am J Physiol Cell Physiol 283: 735-742). Here, we carried out measurements on single myofibrils from rabbit psoas muscle to investigate steps in unactivated specimens in more detail. Activated and unactivated myofibrils were released and stretched in ramp-like fashion. The time course of length change in the single sarcomere was consistently stepwise. We found that in the unactivated myofibrils, step size depended on initial sarcomere length, diminishing progressively with increase of initial sarcomere length, whereas in the case of activated sarcomeres, step size was consistently 2.7 nm. 相似文献
49.
Usefulness of immunohistochemistry in delineating renal spindle cell tumours. A retrospective study of 31 cases 总被引:3,自引:0,他引:3
Wang J Weiss LM Hu B Chu P Zuppan C Felix D Rausei-Mills V Chase DR 《Histopathology》2004,44(5):462-471
AIMS: To assess the usefulness of immunohistochemistry in delineating tumour diagnoses on a series of morphologically diagnosed renal spindle cell tumours (RSCTs). METHODS AND RESULTS: Formalin-fixed paraffin-embedded tissues from 31 morphologically diagnosed tumours were reinterpreted in light of newly obtained immunohistochemical information. By morphology, six had originally been classified as sarcomatoid carcinoma, five as spindle cell tumour (NOS), four as sarcoma (NOS), three as leiomyoma, three as leiomyosarcoma, and one each as fibrous polyp, hamartoma, neurilemmoma, mesoblastic nephroma, medullary fibroma, angiomyolipoma, haemangiopericytoma, malignant rhabdoid tumour, malignant Triton tumour, and carcinosarcoma. The application of immunohistochemistry verified the original diagnosis in 18 cases (18/31, 58%), confirming the diagnosis of sarcomatoid renal carcinoma (4/6), leiomyoma (2/3), leiomyosarcoma (3/3), sarcoma (NOS) (2/4), carcinosarcoma (1/1), malignant rhabdoid tumour (1/1), malignant Triton tumour (1/1), fibrous polyp (1/1), mesoblastic nephroma (1/1), hamartoma (1/1), and angiomyolipoma (1/1). Different tumour designations were suggested in 13 cases (13/31, 42%), including carcinosarcoma, sarcoma (NOS), leiomyosarcoma, solitary fibrous tumour, monomorphic/biphasic angiomyolipoma, endometrial stromal tumour, and congenital mesoblastic nephroma. CONCLUSIONS: Our data indicate that although morphology is most important in formulating the initial differential diagnosis, the addition of immunohistochemistry is vital in arriving at the correct classification of RSCTs. 相似文献
50.
Timo D Müller Anke Hinney André Scherag Thuy T Nguyen Felix Schreiner Helmut Schäfer Johannes Hebebrand Christian L Roth Thomas Reinehr 《BMC medical genetics》2008,9(1):85