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11.
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   
12.
Background: The diffuse sclerosing variant of papillary thyroid carcinoma (DSV-PTC) is an uncommon tumor making up about 2% of all papillary thyroid carcinomas. Previous studies have not comprehensively evaluated these tumors in a large series of patients. Design: Twenty-two cases of DSV-PTC diagnosed between 1970 and 2000 were identified in the files of the AFIP. Histologic and immunohistochemical features were evaluated and patient follow-up was obtained. Results: The tumors affected 14 females and 8 males, aged 6 to 49 yr (mean, 18 yr), with males presenting at a mean older age than females (24 vs 14 yr). Symptoms included an enlarging mass in the thyroid, present for a mean of 9.5 mo. While a dominant tumor was identified in a single lobe, bilateral disease was common (n=16). The dominant mass ranged in size from 1.7 to 5.8 cm in diameter (mean, 3.8 cm). Histologically, all cases demonstrated a papillary carcinoma (conventional, solid, or follicular pattern) diffusely involving the gland. Extrathyroidal extension, lymphocytic thyroiditis, squamous metaplasia, increased fibrosis/sclerosis, and psammoma bodies were present to a variable degree. Both the papillary carcinoma and squamous metaplasia cells were strongly immunoreactive with CK19, thyroglobulin, and TTF-1. An increased number of S-100 protein immunoreactive dendritic cells were recognized. p53 was increased (>15%) in the tumor cells in 12 patients, while Ki-67 was increased in the tumor cells in two patients. Perithyroidal and cervical lymph node metastasis occurred in 18 (82%) patients. All metastases demonstrated histologic features similar to the primary. Complete resection (thyroidectomy in 18 patients) with lymph node dissection, yielded a 95% 5-yr survival without evidence of disease. One patient died of disease after a malignant transformation of the squamous metaplasia into squamous cell carcinoma. Conclusions: The recognition of DSV-PTC can be made with the following features: classic to solid foci of PTC, lymphocytic thyroiditis, squamous metaplasia, increased fibrosis, and innumerable psammoma bodies. DSV-PTC is more biologically aggressive than conventional PTC, but the patients’ survival is not significantly different. This diagnosis should lead the clinician to aggressively manage these patients (thyroidectomy and lymph node dissection) in an effort to achieve an excellent long-term clinical outcome.  相似文献   
13.
The purpose of the present paper was to examine the level of apoptosis and the relationships among apoptosis, apoptosis-associated proteins, and proliferating potential in lymphoma tissues to clarify the characteristics of apoptosis in diffuse large B-cell lymphomas (DLBCL) of the central nervous system (CNS). The formalin-fixed, paraffin-embedded tissues of CNS and non-CNS DLBCL (20 cases each) were studied by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) and immunohistochemistry, using antibodies against single-stranded DNA (ssDNA), cleaved caspase-3, bcl-2, bax, p53, Fas and Ki-67. The cleaved caspase-3 immunohistochemistry detected apoptosis of the lymphoma cells most sensitively compared to TUNEL and ssDNA immunohistochemistry. High expression (grade + + or + + +) of cleaved caspase-3 was found more frequently in CNS DLBCL (11 cases, 55%) than non-CNS DLBCL (three cases, 15%; P = 0.009). Bax-positivity of lymphoma cells was increased in six cases of CNS DLBCL, which also showed high positivity of cleaved caspase-3. There was no significant correlation between the cleaved caspase-3-positivity and the Ki-67 positivity. The present study indicates that the number of apoptotic cells and expression level of cleaved caspase-3 were significantly higher in CNS DLBCL than non-CNS DLBCL, and that the correlation of bax and cleaved caspase-3 expression was often present in CNS DLBCL.  相似文献   
14.
15.
Non-alcoholic fatty liver disease (NAFLD), also referred to as metabolic associated fatty liver disease (MAFLD), is the commonest form of chronic liver disorder arising from metabolic dysregulation. It encompasses a wide spectrum of fatty liver phenotypes including isolated steatosis to non-alcoholic steatohepatitis (NASH). NASH is considered more likely to lead to grave clinical consequences such as cirrhosis and hepatocellular carcinoma, compared to simple steatosis. NASH is characterised by steatosis, inflammation, and damage to hepatocytes. Here, we present a case of a middle-aged gentleman with a background of infectious hepatitis who presented with NASH, with emphasis on terminology and histological assessment criteria of NAFLD and NASH. Reflection on and consistent effort to standardise terminology and assessment criteria will aid in addressing the scientific and clinical needs of NAFLD and NASH.  相似文献   
16.
Analysis of hypermutation of the 5’ noncoding region in the BC L-6 gene   总被引:3,自引:0,他引:3  
Objective To investigate BCL-6 gene mutations in Chinese populations with B-cell non- Hodgkin’s lymphoma.Methods Polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE) and direct DNA sequencing were used to identify mutations in the 5’ noncoding re gion of the BCL-6 gene in a total of 40 cases of diffuse large-cell lymphoma ( DLCL) and follicular lymphoma (FL).Results Nine cases were found to have base substitutions.The incidence of BCL-6 gene mutation and the frequency of single-base changes were approximately 25.7% an d (0.56-1.10)×10(-2)/bp, respectively.Conclusions The 5’ regulatory region of the BCL-6 gene undergoes frequent somatic hypermuta tion during lymphomagenesis and the identification of BCL-6 gene hypermutations provides a molecular marker for confirmatory diagnosis of B-NHL.  相似文献   
17.
目的 通过对脑弥漫性轴索损伤 (DAI)临床、CT及MRI的影像学表现的分析 ,以期提高对DAI的诊断水平。方法 分析有完整临床资料 ,同时进行过CT和MRI检查 ,特别是CT检查相对阴性的 32例DAI患者的影像学诊断结果。结果  32例DAI患者CT检查相对阴性 ,MRI检查发现在胼胝体、基底节、脑干及灰白质交界处多发小的异常信号灶。结论 临床拟诊DAI的患者在CT检查相对阴性时可进行MRI检查 ,其MRI影像学表现有助于DAI的诊断  相似文献   
18.
目的:提高弥漫型肝癌的诊断率。方法:对92例弥漫型肝癌的超声图像特征、临床特点进行回顾性研究。结果:弥漫型肝癌肝大小、形态、包膜、肝内回声、门脉等在超声图像上有一定的特征性改变及有其它临床特征。结论:超声检查在弥漫型肝癌的诊断中具有重要价值。  相似文献   
19.
利用Marmarou氏脑损伤动物模型,测定大鼠脑损伤后不同时间和部位的丙二醛(MDA)含量。结果示:损伤后1h,额叶、顶叶、脑干等处的MDA水平分别比对照组高出367%,418%和351%(P<0.01),并持续增高,伤后4h达高峰后缓慢下降,伤后24h仍明显高于对照组。纹状体、颞叶等处伤后1h的MDA水平升高较上述部位稍低,而分别较对照组升高169%和133%(P<0.01),伤后4h虽仍持续升高,但不超过35%。提示在大鼠弥漫性脑损伤后短期内即有自由基生成,几乎波及脑内各个部位,但程度不一。  相似文献   
20.
Background: The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer.Methods: Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis.Results: p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P < .05), confirmed by multivariate analysis (P < .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression.Conclusions: These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes.  相似文献   
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