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131.
A new form of morphogenesis of pathological process, cystopathy, was distinguished on the basis endoscopy data and morphofunctional analysis of the urinary bladder in chronic cystitis. Cystopathy is characterized by predominance of diffuse degeneration and atrophy of the urothelium, stromal sclerosis, absence of inflammatory cell infiltration, and inhibition of biosynthetic reactions in urothelial cells (compared to chronic cystitis). Cystopathy results from regeneratory and plastic failure. Instability of the bladder epithelium can be a morphological marker of oncological risk.  相似文献   
132.
133.
The effects of capsaicin on urinary bladder function have been investigated in adult rats. Ten days after capsaicin treatment immunocytochemical investigations showed a nearly complete disappearance of substance P (SP) and calcitonin gene-related peptide (CGRP) in all parts of the bladder. Recordings of micturition patterns and cystometrical investigations in conscious animals revealed no functional effects of capsaicin treatment. In-vitro experiments showed that the contractile response to substance P was similar before and after capsaicin treatment and CGRP exerted no contractile effects on the urinary bladder in either group of rats. The concentration–response curve to carbachol as well as the frequency-response curve to electrical stimulation were significantly shifted to the left in bladder muscle after capsaicin treatment. However, the maximal responses were similar in control and capsaicin-treated bladders. In the presence of scopolamine the maximal response to electrical stimulation was clearly lower in bladders subjected to capsaicin treatment than in controls. In conclusion, depletion of substance P and CGRP in the rat urinary bladder by capsaicin induced no supersensitivity to these peptides. However, the increased sensitivity to carbachol and to electrical stimulation seen after capsaicin treatment indicates the development of a supersensitivity to muscarinic receptor stimulation. Despite this supersensitivity in vitro no functional effects of capsaicin treatment were found in vivo.  相似文献   
134.
Sarcomatoid carcinoma is a rare variant of malignant tumor arising from the urinary tract. This tumor had been termed carcinosarcoma because of its carcinomatous and sarcomatous components. There is still some confusion in the terminology between true carcinosarcoma and sarcomatoid carcinoma; however, the latter is now regarded as primarily a malignant epithelial tumor with pseudosarcomatous transformation.
Four cases of sarcomatoid carcinoma arising from the urinary tract are reported. The patients were a 77 year old female, and three males aged 62, 69 and 80 years. All but the eldest patient complained of gross hematurla. Surgical removal was performed in the younger three cases, and an autopsy was done in the remaining case. All the tumors were macroscopically polypoid. Histopathologic examination revealed fasciculated spindle-cell tumors with myxold stroma or malignant fibrous histiocytoma-like spindle cell tumors. The epithelial nature was proven in these sarcomatous cells by immunohistochemical andlor electron-microscopic examinations. Only a small amount of squamous cell carcinoma components was also evident in the latter three cases. Although the younger three patients were alive at 44, 23 and 39 months'follow-up, respectively, constant careful monitoring Is recommended.  相似文献   
135.
Chiu KC  Fine M  Ikle D  Slovak ML  Arber DA 《Human pathology》2003,34(12):1259-1264
Cell proliferation may be evaluated by various methods, including Ki-67 immunohistochemistry and measures of telomerase activity. Both methods would theoretically show comparable increases in a given case. To evaluate the relationship between these 2 markers of proliferation in aggressive mature B-cell lymphomas, 48 cases were studied. The study group included 5 cases of mantle cell lymphoma (MCL); 6 cases of Burkitt's/Burkitt's-like lymphoma (BL); 9 cases of follicular lymphoma, grade 3 (FLC); and 28 cases of diffuse large B-cell lymphoma (DLC). Telomerase activity was measured as total product generated (TPG) units, and TPG results for the aforementioned cases were compared to the TPG results for 10 cases of reactive follicular hyperplasia. An overlap in TPG scores between reactive cases and lymphoma cases was found. Significant differences in both log TPG (P = 0.0443) and Ki-67 (P = 0.0006) were seen in the different lymphoma types. A positive correlation between Ki-67 percentage and TPG score was identified in FLC (r = 0.9281; P = 0.0003), but a poor correlation between these 2 indicators was seen in the other lymphoma types. Cluster analysis identified distinct patterns for MCL, FLC, and BL, but heterogeneous patterns for DLC. Because increases in both Ki-67 proliferation and telomerase activity are reported in normal germinal centers (GCs), these tests were also evaluated for usefulness as markers of a GC cell phenotype. Among the FLC and DLC cases, features of a GC phenotype significantly correlated with increased Ki-67 percentage (P = 0.0152), but not with increased log TPG. An elevated log TPG correlated with CD10 expression, and elevated Ki-67 percentage correlated with both CD10 and BCL-6 expression. TPG level and Ki-67 percentage did not correlate with the presence of t(14;18) or BCL-2 protein expression. Although the proliferation patterns were fairly distinctive for MCL, FLC, and BL, these studies show that markers of cell proliferation do not by themselves,identify distinct subtypes of large cell lymphomas. With the exception of FLC, the tumors exhibited poor correlation between telomerase activity and Ki-67 proliferation index. These tests did show some correlation with expression of GC cell phenotypic markers, however.  相似文献   
136.
The role of a telomerase assay in the recognition of Sertoli cell-only syndrome with testicular foci of haploid cells was evaluated. Men with Sertoli cell-only syndrome (n = 23) were given a new diagnostic testicular biopsy. Part of the biopsy was stained and the remainder was processed for the quantitative telomerase assay. After 3-13 months, a therapeutic testicular biopsy was performed. This material was minced and then examined using confocal laser scanning microscopy and fluorescent in-situ hybridization. Histology of diagnostic testicular biopsy material confirmed the diagnosis of Sertoli cell-only syndrome in all the participants. All seven men with a telomerase assay value in their diagnostic testicular biopsy of >42 total product generated (TPG) U/microg protein had haploid cells (i.e. spermatozoa and/or spermatids) in their therapeutic testicular biopsy. Among participants with telomerase assay values <42 TPG U/microg protein, only one man had haploid cells in his therapeutic testicular biopsy. Thus, telomerase assay values >42 TPG U/microg protein in the diagnostic biopsy identified 87.5% of the Sertoli cell-only syndrome men with haploid cells in their therapeutic testicular biopsy. Significantly higher values of the telomerase assay were found in men with testicular foci of haploid cells than in men without these foci. The use of a quantitative telomerase assay biopsy appears to be important for identifying those men with Sertoli cell-only syndrome who have foci of haploid cells and can be candidates for assisted reproduction techniques.  相似文献   
137.
Pitfalls in TRAP assay in routine detection of malignancy in effusions   总被引:5,自引:0,他引:5  
Telomerase has been found to be reactivated in a majority of cancers but is inactive in most somatic cells. Our principal goal was to determine the potential use of the telomeric repeat amplification protocol (TRAP) assay as marker for malignancy in cytological effusions. The simple selection criterion was the cytological diagnosis, and routine samples were classified into malignant (58 samples) and nonmalignant (233 samples). Of the malignant samples, 44/58 (76%) were positive by TRAP assay. Of the 14 telomerase-negative cytology-positive samples, RNA integrity was poor in 9, indicating suboptimal sample conservation for molecular analysis. In 3 of the remaining 5 samples with a negative TRAP assay, a high number of malignant cells was observed, and these cells might have been telomerase-negative. Thus, the sensitivity of TRAP assay for the presence of malignant cells was about 76%. In the cytologically nonmalignant effusions, the presence of telomerase activity was observed in 24% (55/233). Of these, 6% were highly suspicious for malignancy, 9% were doubtful, and 9% were cytologically nonmalignant effusions confirmed by a follow-up of 12 mo or more. According to these data, the specificity of the TRAP assay to detect tumor cells in effusions ranged only between 82-91%. Our results indicate that, although the TRAP assay is positive in 6-15% of putative malignant effusions, the relatively high number of TRAP false-negative and false-positive cases renders this test unsuitable for routine diagnostic purposes.  相似文献   
138.
AIMS: Detection of telomerase catalytic subunit (hTERT) mRNA has been used as a surrogate marker for estimation of telomerase activity. The exact role and timing of telomerase re-activation, a key enzyme implicated in cellular immortalization and transformation, in the multistep process of oral carcinogenesis is still unknown. The aim was to test the hypothesis that (i) quantitative rather than qualitative differences exist in the level of hTERT mRNA expression between normal oral mucosa, different grades of oral epithelial abnormalities and squamous cell carcinomas of the oral cavity, and that (ii) hTERT gene re-expression is an important, probably early event in oral carcinogenesis. METHODS AND RESULTS: The relative quantity of hTERT mRNA was analysed in 45 frozen oral epithelia representing different morphological stages of oral carcinogenesis classified according to the Ljubljana classification and in 37 oral squamous cell carcinomas, using a commercially available LightCycler Telo TAGGG hTERT Quantification kit. hTERT mRNA was not detected in normal or reactive hyperplastic oral epithelia, but was present in 43% of atypical hyperplasias (premalignant lesions), 60% of intraepithelial carcinomas and 68% of oral squamous cell carcinomas. Statistical analysis revealed two groups of oral epithelial changes, with significant differences in the levels of hTERT mRNA expression: 1, normal and reactive hyperplastic oral epithelium, and 2, atypical hyperplasia, intraepithelial carcinomas and squamous cell carcinomas. CONCLUSION: These data suggest that hTERT gene re-expression represents an early event in the multistep process of oral carcinogenesis, already detectable at the stage of precancerous oral epithelial changes. Nevertheless, other genetic aberrations appear to be necessary for progression of oral epithelial abnormalities towards invasive squamous cell carcinoma.  相似文献   
139.
This study investigated the clinical characteristics of ciprofloxacin-resistant Proteus mirabilis isolates from urine samples associated with nosocomial infection or colonisation, and identified the risk-factors for ciprofloxacin resistance. Data for patients with ciprofloxacin-resistant P. mirabilis isolates (n=13) were compared with those for randomly selected patients with ciprofloxacin-susceptible P. mirabilis isolates (n=40) who were matched by temporal occurrence as control patients. The majority of ciprofloxacin-resistant P. mirabilis isolates were multiresistant, and ciprofloxacin resistance was associated significantly with previous use of fluoroquinolones and production of extended-spectrum beta-lactamases.  相似文献   
140.
The present study attempted to clarify the significance of aberrant expression of beta-catenin protein and mutation of exon 3 of the beta-catenin gene in renal and urothelial carcinogenesis. beta-Catenin expression was examined immunohistochemically and mutation of the beta-catenin gene was analyzed by polymerase chain reaction-single strand conformation polymorphism (SSCP) and direct sequencing. beta-Catenin immunoreactivity was observed at the cell membrane in all 30 renal cell carcinomas (RCC) examined, and no RCC showed a mobility-shifted SSCP band. Of 46 transitional cell carcinomas (TCC) examined, there was reduced expression of beta-catenin, as compared with its expression in non-cancerous transitional epithelium, in 22 cases (48%) and beta-catenin accumulation in the nucleus in five cases (11%). Of four renal pelvis TCC examined, point mutation of exon 3 of the beta-catenin gene at codon 45 resulting in amino acid substitution (Ser to Phe) was detected in one (25%). The incidence of reduced expression of beta-catenin correlated significantly with the growth pattern (superficial type vs invasive type) of TCC (P < 0.05). These data indicate that: (1) aberrant beta-catenin expression may be at least partly involved in urothelial carcinogenesis, but less significantly so in renal carcinogenesis, and (2) it may be associated with the progression of TCC showing invasive growth.  相似文献   
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