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71.
72.
Aki Tanaka Mitsuyoshi Hirokawa Ayana Suzuki Miyoko Higuchi Akira Miyauchi Takashi Akamizu 《Pathology international》2023,73(8):351-357
A preoperative diagnosis of metastatic renal cell carcinoma to the thyroid (MRCCT) is important for determining clinical management but is challenging even in cases with a clinical history of renal cell carcinoma (RCC). This study aimed to elucidate the clinical, cytological, and pathological characteristics of MRCCT. Fourteen MRCCT cases extracted from 18 320 malignant thyroid tumors were included in this study. Twelve MRCCT (85.7%) occurred as solitary lesions and the most frequently suspected lesions on ultrasonography were follicular tumors. On cytology, 46.2% of cases were reported as RCC or suspected RCC; a medical history of RCC and immunocytochemistry were helpful in interpretation. RCC metastasized to a follicular adenoma in 50.0% of the solitary lesions. MRCCTs with a long interval from the initial presentation, solitary lesion, and Ki-67 labeling index <10% showed significantly longer disease-free survival. MRCCT is characterized by a long interval from the initial presentation of RCC, appearance as a solitary nodule, ultrasonographic similarity to follicular tumors, sharing cytological findings with primary thyroid tumors, and high frequency of metastasis within follicular adenoma. A long interval from the initial presentation, occurrence as a solitary lesion, and low Ki-67 labeling index may be favorable prognostic factors. 相似文献
73.
Harry T. Whelan Lucy H. Kras Kutlan Ozker Dawn Bajic Meic H. Schmidt Yu Liu Lisa Ann Trembath Fusun Uzum Glenn A. Meyer Annette D. Segura B. David Collier 《Journal of neuro-oncology》1994,22(1):7-13
The use of PHOTOFRIN for photodynamic therapy of human gliomas has been studied by i.v. administration and laser photosensitization. Defining the uptake of PHOTOFRIN in the patient's tumor in comparison with the surrounding normal brain tissue is highly desirable for patient selection and study ofin vivo kinetics. We utilized a non-invasive approach to the detection of PHOTOFRIN uptake in brain tumors with111In-oxine radiolabeled PHOTOFRIN and external imaging and quantitation using a gamma camera. Biodistribution of111In-labeled PHOTOFRIN in 13 organs was determined in four dogs and 15 mice with gliomas.99mTc-DTPA was used as a control for nonspecific uptake. The greatest concentration of111In-PHOTOFRIN in the brain tumor occurred at 24 hours post i.v. administration. The brain tumor PHOTOFRIN uptake was seven times greater than that of normal brain. The decreased blood background at 72 hours made this the optimum time for imaging. Specific tumor tissue uptake of111In-PHOTOFRIN occurred, well beyond that resulting from blood-brain-barrier (BBB) breakdown. 相似文献
74.
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
75.
76.
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
77.
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
78.
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
79.
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
80.
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