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71.
Triple approach for diagnosis and grading of meningiomas: Histology,morphometry of Ki-67/feulgen stainings,and cytogenetics 总被引:5,自引:0,他引:5
H. Kolles I. Niedermayer Ch. Schmitt W. Henn R. Feld W. I. Steudel K. D. Zang W. Feiden 《Acta neurochirurgica》1995,137(3-4):174-181
Summary With regard to meningioma grading and the recently introduced atypical meningioma, we evaluated 160 cases retrospectively by conventional histology and image analysis. For that, the cell nuclei were stained with a Ki-67 (MIB1)/Feulgen-method on paraffin sections, thus enabling the assessment of both the Ki-67 proliferation index and nuclear morphometric features, such as tumour cell arrangement, nuclear pleomorphism, and cellularity.It could be demonstrated that the Ki-67 proliferation index is the most important criterion for distinguishing anaplastic meningiomas (WHO grade III) (mean Ki-67 index: 11%) from those of common type (WHO grade I) (mean Ki-67 index: 0.7%). The parameter for the relative volume weighted mean nuclear volume is another valuable morphometric feature. The atypical meningioma (WHO grade II) which should represent an intermediate category between common type and anaplastic meningiomas is characterized by a mean Ki-67 proliferation index of 2.1%. Common type meningiomas which comprise almost 50% of the cases of this series have a relapse rate of 9%. Atypical and anaplastic meningiomas recurred in 29% and 50%, respectively. Since the term atypical meningioma is confusing in the context of tumour grading, the term intermediate type meningioma is proposed.Furthermore, the results of cytogenetic analyses of 142 cases of this series were evaluated and compared with the meningioma grades. Thereby, 25 cases disclosed, independent of the typical loss of one chromosome 22, cytogenetic features assumed to be progression-associated, e.g., the gain or loss of different chromosomes and the deletion of the short arm of one chromosome 1 (hyperdiploidy, increased hypodiploidy, Ip-), when correlated to the histological and morphometric findings or the high relapse rate.For meningioma diagnosis and grading, a practical guideline is proposed based upon histology, morphometry (Ki-67), and cytogenetics. 相似文献
72.
73.
The Expression of the antiapoptotic oncoprotein BCL-2 and its correlation to tumor grade in 62 meningiomas (48 classic, 9
atypical, and 5 anaplastic) using single and double immunohistochemistry was investigated. BCL-2 expression was found in two
different cell populations identified as lymphocytes (BCL-2+CD3+) and tumor cells (BCL+/CD3–). Tumor-infiltrating lymphocytes
(TIL) (CD3+) were found within classic (9.5% of cells), atypical (2.4% of cells), and anaplastic (1.8% of cells) meningiomas.
In classic meningiomas, 66.5% of TIL were BCL-2-positive, in atypical meningiomas 79.2%, and in anaplastic meningiomas 37.9%.
In 33 (68.8%) of the classic meningiomas, medium to high counts of BCL-2+ tumor cells were detected. Atypical meningiomas
showed nearly equal percentages of high (two patients), medium (five patients), and low (two patients) BCL-2+ tumor cell counts,
whereas anaplastic meningiomas showed only medium (two patients) and low (three patients) BCL-2 tumor cell counts or were
BCL-2-negative (one patient). In summary, a significant inverse correlation between the number of BCL-2-positive tumor cells
and tumor grade in meningiomas was found. These findings support the hypothesis of cell survival prolongation by the antiapoptotic
ability of BCL-2 proto- oncogenes and demonstrate the prognostic relevance of BCL-2 immunoreactivity in meningiomas.
Received: 10 June 1998 / Accepted: 23 February 1999 相似文献
74.
Raghavan Krishnaswamy S. Gray David B. Scholz Thomas H. Nemeth Gregory A. Hussain Munir A. 《Pharmaceutical research》1996,13(12):1815-1820
Purpose. The objective was to evaluate the degradation profile of the elastase inhibitor DMP 777 and lay the foundation for formulation development.
Methods. The pKa was determined by potentiometric titration in mixed-aqueous solvents. The degradation kinetics were studied as a function of pH, buffer concentration, ionic strength, methanol concentration and temperature using a stability-indicating HPLC assay. The degradation products were identified by LC-MS, NMR, and by comparison with authentic samples.
Results. The pKa for the protonated piperazine nitrogen was estimated to be 7.04. The pH-rate profile is described by specific acid-, water-, and specific base-catalyzed pathways. The pH of maximum stability is in the range of 4 to 4.5 where water is the principal catalyst in the reaction. Buffer catalysis, primary salt effects and medium effects were observed. The proposed mechanism for acid catalyzed degradation is the rarely observed AAL1 which involves alkyl-nitrogen heterolysis. The driving force for the reaction appears to lie in the stability of the benzylic carbocation. The proposed mechanism for base catalyzed degradation is BAC2 which involves -lactam ring opening. The -lactam ring of DMP 777, a monolactam, appears to be as reactive as that in benzylpenicillin in the k
OH controlled region where a similar mechanism of hydrolysis should be operative. A contributing factor to this increased reactivity may lie in the reduced basicity of the -lactam nitrogen making it a good leaving group.
Conclusions. The degradation profile indicates that development of a solution dosage form of DMP 777 with adequate shelf-life stability at room temperature is feasible. 相似文献
75.
Andrea Bonetti Marta Zaninelli Stefania Rodella Annamaria Molino Loris Sperotto Quirino Piubello Franco Bonetti Rolando Nortilli Monica Turazza Gian Luigi Cetto 《Breast cancer research and treatment》1996,38(3):289-297
Summary The relationship between tumor proliferative activity and response to first-line chemotherapy and survival was investigated in 76 advanced breast cancer patients. Proliferative activity was determined by means of Ki-67 immunohistologic staining on primary tumors (55 patients) or at the relapse site (21 patients), and was classified as low ( 25% of stained cells) or high (> 25% of stained cells). The usual WHO response criteria were used. The median duration of follow-up was 18 months (range 3–58).Forty-seven patients (62%) had tumors with low, and 29 (38%) had tumors with a high rate of proliferative activity. The two groups were well balanced in terms of important variables such as disease-free survival, performance status, age, menopausal status, and the type of first-line chemotherapy (anthracycline-based regimens versus cyclophosphamide-methotrexate-5-fluorouracil). The estrogen receptor (ER) content, measured by means of immunohistochemical assay, was markedly different in the two groups, with 27/47 tumors with low proliferative activity (57%) and 6/29 with high-proliferative activity (21%) being ER positive ( 45% of stained cells) (p = 0.003). Moreover, a significant difference in the metastatic pattern was also evident, with a higher incidence of bone and a lower incidence of soft tissue metastases in the group of patients with tumors with low proliferative activity (p = 0.004). Overall, 10/47 responses (21%: PR = 7, and CR = 3) were observed in the group with a low rate of proliferative activity, versus 14/29 (48%: PR = 9, and CR = 5) in the group with highly proliferative tumors, the difference being statistically significant (p = 0.03). When a multivariate analy-sis was performed, the only factor that retained independent prognostic significance was the predominant site of disease, particularly soft tissues (p = 0.003). Despite the difference in response rate, when survival analysis was performed according to the Kaplan-Meier method, no significant difference was observed in the two groups, but when the analysis was limited to responsive patients, the median survival observed in those with a low and those with a high rate of proliferation was 35 and 19 months respectively (p = 0.02). The same results were obtained when multivariate survival analysis was carried out using Cox's regression model. These data suggest that there is a link between tumor proliferative activity and response to chemotherapy in advanced breast cancer, and may indicate the need to use more intensive treatments in selected patients with highly proliferative tumors.Presented in part at the Annual Meeting of the American Society of Clinical Oncology, May 14–17, 1994, Dallas, TX, USA 相似文献
76.
Francisco José H. N. Braga Elaine B. Araújo Edwaldo E. Camargo Leontina C. M. Tedesco-Marchesi Maria Cecilia M. Rivitti Hateme Bouladour Pierre Galle 《European journal of nuclear medicine and molecular imaging》1991,18(11):866-869
Gallium 67 imaging was used in 12 patients with documented Hansen's disease undergoing treatment or not, in an attempt to determine the pattern of the disease. Diagnosis was confirmed by histopathology in all patients. The Mitsuda reaction was seen in all patients. Specific nuclear studies were performed when needed to evaluate particular organs better. Gallium 67 images show homogeneous, diffuse and moderate accumulation over the entire skin surface (except for the face) of untreated patients with multibacillary disease. The facial skin in these cases presented homogeneous, diffuse but very marked uptake of gallium. Internal organ involvement was variable. There was a very good correlation among clinical, scintigraphic, immunological and histopathological data. The pattern of the body skin (skin outlining) and facial skin (beard distribution) may be distinct for untreated patients with multibacillary leprosy. 相似文献
77.
Summary The origin of the extracellular -amyloid protein (/A4) found in senile plaques and the cellular mechanisms responsible for its deposition in cerebral tissues are still an unresolved issue in Alzheimer's disease. In this study we analyzed in detail the distribution of various epitopes of /A4 in relation to local cellular elements in diffuse plaques of the hippocampal region. We also correlated our findings with the presence and distribution of non-/A4 epitopes of the amyloid precursor protein (APP) and with synaptophysin immunoreactivity in the cortical neuropil. Discontinuous /A4-immunoreactive deposits were found along dendrites, and around the soma of neurons included in the plaques. Furthermore, increased synaptophysin reactivity with slightly dilated synaptophysin-immunolabeled presynaptic terminals were found in diffuse plaques. APP epitopes could not be found in diffuse plaques. However, some of the APP antibodies, mainly those to the C-terminal portion of APP, and antibodies to /A4 recognized clusters of flat vesicular profiles (0.6–1.4 m in width and 2–3 m in length) in the neuropil of cortical areas where plaques had developed. Our findings are compatible with a neuronal origin of /A4 in diffuse plaques and with a primary release of /A4 at synaptic sites along the immunostained neurites. They also suggest that diffuse plaques might be preceded by minute lesions of the neuropil where /A4 is not yet released from the precursor molecule. 相似文献
78.
通过使用补肾活血合剂后对SHR和Wistar大鼠血压、主动脉及主动脉中膜平滑肌细胞碱性成纤维细胞生长因子 (bFGF)和Ki- 6 7阳性表达的观察 ,探讨了补肾活血合剂在降低血压、改善高血压血管损害中的作用机制 ,提示补肾活血合剂所调控的生长因子 (bFGF、Ki- 6 7)与血管损害的特异性有关。 相似文献
79.
目的 :探讨MMP 2、TIMP 2、Ki 67表达与库肯勃氏瘤病理生物学行为的关系。方法 :采用免疫组化SP法对 32例库肯勃氏瘤组织和 10例正常卵巢组织进行MMP 2、TIMP 2和Ki 67表达的检测。结果 :MMP 2、TIMP 2、Ki 67在库肯勃氏瘤组织中的表达量显著高于正常卵巢组织 (P <0 .0 1)。有合并转移的库肯勃氏瘤中MMP 2、Ki 67高于无合并转移者 (P <0 .0 5 ) ,TIMP 2低于无合并转移者 (P <0 .0 5 )。MMP 2、Ki 67与术后生存时间呈负相关 (P <0 .0 1) ,TIMP 2与术后生存时间呈正相关 (P <0 .0 1)。结论 :MMP 2、TIMP 2、Ki 67在库肯勃氏瘤发生、发展中起重要作用 ,可作为判断卵巢转移癌恶性程度、临床分期和评估预后的临床参考指标 相似文献
80.
表皮生长因子受体EGFR和Ki67在非小细胞肺癌中的表达及其相关性研究 总被引:1,自引:0,他引:1
目的 :探讨表皮生长因子受体 (epi dermalgrowthfactorreceptor ,EGFR)和Ki67在非小细胞肺癌 (non smallcelllungcancer,NSCLC)中的表达及其与NSCLC发生、发展及预后的关系。方法 :对经随访资料完整的术后NSCLC组织标本 60例、癌旁组织 2 0例和肺正常组织 5例 ,采用SP免疫组化法检测EGFR和Ki67。对术后辅助性化疗 3 6例 ,分析疗效与EGFR和Ki67表达的关系。结果 :NSCLC中EGFR表达阳性率为 65 % ,阳性细胞的棕黄色颗粒位于细胞质 ;Ki67表达阳性率为 81 67% ,阳性细胞的棕黄色颗粒位于细胞核 ;2 0例癌旁组织及 5例正常肺组织未见阳性染色细胞。癌组织EGFR和Ki67表达与癌旁组织相比差异有统计学意义 ,P <0 0 1。NSCLC中EGFR和Ki67阳性表达与年龄、性别、吸烟与否、肿瘤细胞的病理类型差异无统计学意义 ,P >0 0 5 ;与肿瘤大小、病理分级、淋巴结转移和TNM分期密切相关 ,P <0 0 5。EGFR和Ki67表达阳性者 3年生存率分别为19 86%和 3 1 3 3 % ,低于阴性表达 70 11%和90 91% ,P <0 0 5 ;接受术后辅助性化疗的患者 ,EGFR和Ki67阳性表达复发转移率分别为 70 3 7%和 62 5 0 % ,高于阴性表达 11 11%和 0 ,P <0 0 5。结论 :EGFR和Ki67在NSCLC中的异常或过度表达与肿瘤发生、发展密切相关 ,两者表达具有协同作 相似文献