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11.
Human papillomavirus is associated with a variety of anogenital lesions, including genital warts, precancers and cancers. In male patients human papillomavirus has been identified in proliferative lesions ranging from penile and urethral warts to penile and prostatic cancers. We examined the association of human papillomavirus deoxyribonucleic acid (DNA) in 84 prostate tissue specimens. Specimens were selected from radical prostatectomy, transurethral resection or transrectal biopsy procedures. A total of 60 formalin-fixed, paraffin-embedded tissues (24 prostate cancer specimens, 16 benign prostatic hyperplasia specimens and 20 normal specimens) was examined by polymerase chain reaction and in situ hybridization. Also, 24 gelatin-embedded frozen prostate cancer specimens were examined for human papillomavirus DNA by polymerase chain reaction. Of the specimens 69 were deemed adequate for polymerase chain reaction analysis, whereas all 60 paraffin-embedded tissues were sufficient for in situ hybridization. Human papillomavirus DNA was detected in 2 normal tissues and 6 prostate cancers using polymerase chain reaction. None of the benign prostatic hyperplasia specimens was positive for human papillomavirus. Human papillomavirus typing results indicated that virus type 16 was present in each of the 8 positive specimens. Confirmation of the presence of human papillomavirus was obtained for 1 of the prostate cancers by nonisotopic in situ hybridization with biotinylated human papillomavirus genomic probes. The low prevalence of human papillomavirus in this study population does not strongly support an etiological role for the virus in prostate cancer.  相似文献   
12.
We investigated the effects of ice massage, ice massage with exercise, and exercise on the prevention and treatment of delayed onset muscle soreness (DOMS). Twenty-two subjects were randomly assigned to one of four groups. Preexercise measures were recorded for range of motion (ROM), strength, perceived soreness, and serum creatine kinase (CK) levels. Subjects performed up to 300 concentric/eccentric contractions of the elbow flexors with 90% of their 10 repetition maximum to induce muscle soreness. Dependent variables were assessed at 2, 4, 6, 24, 48, 72, 96, and 120 hours postexercise. Significant differences occurred in all variables with respect to time (ANOVA(p<.05)). However, no significant mode of treatment, or mode of treatment/assessment time interaction was present. Decreases in range of motion and flexion strength correspond with increases in perceived soreness. The nonsignificant mode of treatment/assessment time interaction suggests that the use of ice massage, ice massage with exercise, or exercise alone is not effective in significantly reducing the symptoms of delayed onset muscle soreness. In fact, though not statistically significant, the pattern of the data suggested the use of ice in the treatment of DOMS may be contraindicated. Further investigation is recommended.  相似文献   
13.
14.
Active T cell recognition of islet antigens has been postulated as the pathogenic mechanism in human type 1 diabetes, but evidence is scarce. If T cells are engaged, they are expected to display increased clonal size and exhibit a T helper (Th)1/Th2 differentiation state. We used a peptide library that covers tyrosine phosphatase IA-2, a target antigen expressed in pancreatic beta cells, to probe 8 diabetic patients and 5 HLA-matched controls. When tested in a high resolution IFNgamma/IL-4 double color ELISPOT assay directly ex vivo, the number of IA-2-reactive IFNgamma producing cells was 17-fold higher in patients than in controls and IL-4 producing cells were not present. An average of 9 peptides was recognized in the patients vs. one in the controls. Determinant recognition primarily involved CD4+ cells and showed high variability among the patients. Furthermore, anti-CD28 antibody signal enhances quantitative assessment of effector T cells in T1D patients. In vitro expansion with peptides and IL-2 results in detection of responding cells in the controls and loss of disease specificity of the T cell response. Together these data provide strong evidence for the active targeting of IA-2 by Th1 memory effector cells in human type 1 diabetes.  相似文献   
15.
Human type 1 diabetes is thought to be mediated by autoreactive T cells specific for antigens expressed by pancreatic beta cells. However, it is unclear which autoantigens and determinants thereof are the targets of the autoimmune attack. Using comprehensive peptide libraries that cover the entire sequence of two major candidate autoantigens, GAD65 and proinsulin, we measured the in vivo frequencies of peptide-specific, IFN-gamma-producing memory T cells in 27 diabetic patients, 14 high risk individuals, and 15 partially HLA-matched healthy controls. Compared to the controls, both a higher number of determinants on the islet cell antigens were recognized and the frequencies of peptide specific cells were increased in patients and high risk individuals. Inclusion of signal enhancing anti-CD28 antibody further accentuated this difference. Considerable heterogeneity in peptide recognition was seen even in DRB1*04, DQB1*0302 matched individuals. Unlike its peptides, the GAD protein antigen did not recall a T cell memory response. The highly heterogeneous recognition of a multitude of peptide determinants on both autoantigens, occurring in the absence of protein recognition, and the low functional avidity of the memory cells involved jointly suggest that the autoimmune T cell repertoire in human type 1 diabetes primarily targets cryptic determinants engaged by determinant spreading.  相似文献   
16.
The frequency and the cytokine signature of antigen-specific T cells in the blood reflect the magnitude and the quality of T cell immunity in vivo. Recently, cytokine enzyme-linked immunospot (ELISPOT) assays performed on freshly isolated peripheral blood mononuclear cells (PBMC) emerged as a promising tool for monitoring these key parameters, providing direct feedback information on the efficacy of vaccinations and immune therapies. However, performing ELISPOT assays with freshly isolated cells is not readily feasible in the context of clinical trials. The ability to obtain valid ELISPOT data on cryopreserved samples would greatly enhance ex vivo immune monitoring capabilities. We have therefore systematically studied antigen-specific T cell responses in freshly isolated PBMC and after cryopreservation. Four healthy donors were selected that displayed T cell responses to six recall antigens. The antigen reactive T cells were defined as CD4 or CD8 cells, and their cytokine effector class was established measuring interferon (IFN)-gamma, interleukin (IL)-2, IL-4 and IL-5. The donors were bled at three different time points, and their PBMC were tested fresh and after freeze-thawing. The results showed that the frequencies and type 1/type 2 cytokine signatures of recall antigen-specific CD4 and CD8 cells are unaffected after cryopreservation. In contrast to these data obtained on human PBMC, cryopreservation of murine spleen cells causes a decrease in cytokine secretion.  相似文献   
17.
Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are distinct mental retardation disorders associated with deletions of proximal 15q (q11-q13) of different parental origin. Yeast artificial chromosome (YAC) clones were isolated for 9 previously mapped DNA probes from this region, and for one newly derived marker, LS6-1 (D15S113). A YAC contig of 1-1.5 Mb encompassing four markers (ML34, IR4-3R, PW71, and TD189-1) was constructed. Multi-color fluorescence in situ hybridization (FISH) analysis of interphase nuclei was combined with YAC contig information to provide the following order of markers: cen-IR39-ML34-IR4-3R-PW71-TD189-1-LS6++ +-1-TD3-21-GABRB3-IR10-1-CMW1-tel. FISH analysis was performed on 8 cases of PWS and 3 cases of AS, including 5 patients with normal karyotypes. All eleven patients were deleted for YACs in the interval from IR4-3R to GABRB3. On the proximal side of the deletion interval, 10/10 breakpoints fell within a single ML34 YAC of 370 kb. On the distal side, 8/9 breakpoints fell within a single IR10-1 YAC of 200 kb. These results indicate a striking consistency in the location of the proximal and distal breakpoints in PWS and AS patients. FISH analysis on a previously reported case of familial AS confirmed a submicroscopic deletion including YACs corresponding to LS6-1, TD3-21 and GABRB3 and supports the separation of the PWS and AS critical regions. Since these three YACs do not overlap each other, the minimum size of the AS critical region is > or = 650 kb.  相似文献   
18.
Zusammenfassung Wir untersuchten 23 Patienten mit laparoskopisch oder bioptisch gesichterter Lebercirrhose (10 Patienten ohne Ascites und 13 Patienten mit Ascites). Es wurde die Inulin- und PAH-Clearance und das tubuläre Transportmaximum für PAH bestimmt.Bei Lebercirrhosen ohne Ascites fand sich sowohl eine Verminderung mäßigen Grades der Inulin- und PAH-Clearance als auch eine Einschränkung der Nierendurchblutung. Das tubuläre Transportmaximum für PAH war normal. Bei Ascites fand sich eine deutliche Herabsetzung der Inulin-Clearance und der PAH-Clearance, eine Verminderung der Nierendurchblutung und eine signifikant erhöhte Wasserrückresorption. Das tubuläre Transportmaximum für PAH war im Bereich der Norm. Die Ursachen der Funktionseinschränkung werden diskutiert.
Summary 1. Inulin clearance and PAH clearance was studied in 23 patients withLaennec's cirrhosis, in 13 Patients ascites was demonstrable.2. In patients withLaennec's cirrhosis without ascites, inulin clearance and PAH clearance as well as renal blood flow was lower than normal controls. The maximal rate of tubulär transport for PAH was normal.3. In patients withLaennec's cirrhosis with ascites, inulin clearance, PAH clearance and renal blood flow was very low. Water reabsorption was significant higher than in normal controls. The maximal rate of tubular transport for PAH was normal.4. The results are discussed.
  相似文献   
19.
Zusammenfassung An den KammerwÄnden menschlicher linker Ventrikel, die auf Grund einer Aortenstenose, einer Aorteninsuffizienz oder eines kombinierten Aortenvitium hypertrophiert waren, wurden licht- und elektronenmikroskopisch morphometrische Untersuchungen angestellt. Die Ergebnisse wurden mit denen, die an nicht belasteten menschlichen linken Ventrikeln gewonnen wurden, verglichen.Lichtmikroskopisch unterscheiden sich die Anteile der Volumendichten des Interstitium und der Herzmuskelzellen am gesamten Herzmuskelgewebe nicht statistisch signifikant. Es konnte morphometrisch eine Zellvergrö\erung festgestellt werden, die aus der signifikanten Verringerung der Volumendichte der Zellkerne (P<0,001) und der Anzahl der Zellkerne pro TestflÄche (P<0,0001) gegenüber den beiden Normalkollektiven resultiert. Elektronenmikroskopisch ist eine Zunahme der Volumendichten der Myofibrillen (P<0,0001) auf Kosten des restlichen Cytoplasmas (P<0,001) festzustellen, wÄhrend die Volumendichte der Mitochondrien im Vergleich mit den jungen und alten Patienten abnahm (P<0,0001). Die OberflÄchendichte der Mitochondrien verringerte sich gegenüber den beiden Vergleichskollektiven (P<0,001) ebenso wie die der Cristae mitochondriales (P<0,0001). Diese Ergebnisse finden ihr morphologisches Korrelat in Mitochondriendestruktionen. Eine vermehrte Myolyse hat bei den hypertrophierten Herzen, die alle gewichtsmÄ\ig über dem kritischen Herzgewicht lagen, noch nicht eingesetzt. Bei allen Patienten wurde der herzchirurgische Eingriff mit Erfolg durchgeführt.
Ultrastructural morphometric analysis of hypertrophied human myocardial left ventricles
Summary Biopsies of hypertrophied human myocardial left ventricles were investigated morphometrically. The diagnoses of the patients were stenosis of the aortic valve, aortic insufficiency or a combination of both lesions. The results were compared with those from normally loaded human left ventricles.There are no differences on light microscopical level between the volume densities of interstitial tissue and of heart muscle cells in the three groups of patients. A significant diminution of the volume density of the nuclei (P<0.001) and the number of nuclei per test area (P<0.0001) when compared with normal groups suggests an increase in volume of the single heart muscle cell. The ultrastructural study shows marked increase in volume density of myofibrils (P<0.0001), with accompanying decrease in the volume densities of mitochondria (P<0.0001) and the remaining cytoplasm (P<0.001). A gross decrease in the surface area of mitochondria (P<0.001) and of cristae mitochondriales (P<0.0001) is found. The morphological equivalents of this result are numerous stages of mitochondrial destruction including cristolysis. All myocardial weights were beyond the critical heart weight.
Mit dankenswerter Unterstützung der Deutschen Forschungsgemeinschaft über den Sonderforschungsbereich SFB 104  相似文献   
20.
To obtain a better understanding of the biology behind life-threatening fungal infections caused by Candida albicans, we recently conducted an in silico screening for fungal and host protein interaction partners. We report here that the extracellular domain of human CD4 binds to the moonlighting protein enolase 1 (Eno1) of C. albicans as predicted bioinformatically. By using different anti-CD4 monoclonal antibodies, we determined that C. albicans Eno1 (CaEno1) primarily binds to the extracellular domain 3 of CD4. Functionally, we observed that CaEno1 binding to CD4 activated lymphocyte-specific protein tyrosine kinase (LCK), which was also the case for anti-CD4 monoclonal antibodies tested in parallel. CaEno1 binding to naïve human CD4+ T cells skewed cytokine secretion toward a Th2 profile indicative of poor fungal control. Moreover, CaEno1 inhibited human memory CD4+ T-cell recall responses. Therapeutically, CD4+ T cells transduced with a p41/Crf1-specific T-cell receptor developed for adoptive T-cell therapy were not inhibited by CaEno1 in vitro. Together, the interaction of human CD4+ T cells with CaEno1 modulated host CD4+ T-cell responses in favor of the fungus. Thus, CaEno1 mediates not only immune evasion through its interference with complement regulators but also through the direct modulation of CD4+ T-cell responses.  相似文献   
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