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71.
A 60-year-old Japanese woman was diagnosed at autopsy as having had hereditary hemorrhagic telangiectasia (HHT) associated with systemic hemangiomas. In her repoduction period, premenstrual epistaxis frequently occurred. At the age of 60, the patient died of malignant lymphoma. At autopsy, multiple telangiectatic spots were noted on the face, limbs and trunk. The paraaortic lymph nodes, which were enlarged and irregularly conglomerated, were histologically diagnosed as malignant lymphoma of the diffuse large cell type. Submucosal telangiectatic lesions were found in the gastrointestinal system from the oral cavity to the rectum. Cavernous hemangiomas were present in various visceral organs including the liver, spleen, small and large intestines, rectum, appendix, uterus, and jejunal and colonic mesenteries. There was an arteriovenous fistula in the left lung. Examination of her family pedigree showed that the patient had an autosomal dominant trait of inheritance. The pathogenesis of the systemic visceral hemangiomas observed in this patient was considered to be similar to that of hamartoma.  相似文献   
72.
Summary The successful transplantation of a human malignant histiocytosis into nude mice allowed the examination of its atypical histiocytic cell proliferation. Histiocytic type cells were identified by positive reactions with acid phosphatase and non-specific esterase and with anti human DR or OKI1 antisera. Presence of OKT9 antigen and negative results obtained with most OKT antisera, rosettes, erythrophagocytosis and lysozyme corroborate the histiocytic immature state of the cells and preclude another type of tumor. All positive tests to prove a mature mononuclear phagocytic origin were attributable to the murine host cell reaction.  相似文献   
73.
Summary Diagnosis of malignant histiocytosis (MH) was confirmed in 16 patients. Stage at diagnosis was I–II in nine, and III–IV in seven patients. Poor prognosis and B-symptoms were correlated to advanced stages. Bone marrow biopsy proved most useful to verify organ involvement. Scintigraphy and computerized tomography, too, detected organ involvement in some patients and were helpful for judging response to therapy. Relapses after radiotherapy were frequent. Polychemotherapy using CHOP-combination is recommended for most patients and may in stages I–II be supplemented by primary or secondary involved or extended field irradiation and in more advanced stages by mainbulk-irradiation. The value of prophylactic CNS-therapy remains controversial. Pathophysiological aspects and differential diagnosis are discussed.  相似文献   
74.
Apolipoprotein D (apoD) expression was studied in nonneoplastic peripheral nerve, neurofibromas (NFs), and malignant peripheral nerve sheath tumors (MPNSTs) by quantitative polymerase chain reaction, in situ hybridization, and immunohistochemistry. Multiplex quantitative polymerase chain reaction for messenger RNA was performed on a series of formalin-fixed and paraffin-embedded specimens that included 9 MPNSTs, 12 NFs, and 4 normal peripheral nerves. The average apoD expression was 108-fold decreased (DeltaCt = -7.3) in the MPNSTs compared with the NFs (P < .05). ApoD expression levels were 3.0-fold elevated (DeltaCt = 1.7) in the NFs compared with nonneoplastic peripheral nerve (P < .05). In situ hybridization for apoD RNA was performed on a separate series of 10 cases in which each microscopic section included both MPNST and the NF from which it arose. These studies confirmed elevated apoD expression in NFs compared with MPNSTs and demonstrated that this expression was variable among individual cells within the NFs. Differential expression by immunohistochemistry could only be demonstrated in selected areas, most likely because apoD protein is a small molecule that is secreted out of the cell into the extracellular space and plasma. ApoD expression initially increases a small amount with the formation of NFs from nonneoplastic peripheral nerve and subsequently decreases markedly as NFs transform into MPNSTs. This expression pattern may serve as a marker for cell cycle inhibition during peripheral nerve tumorigenesis.  相似文献   
75.
Summary Thirty men and 7 women with malignant mesothelioma seen at the Free University Hospital from 1st January 1960 until 1st July 1981 were reviewed.The histological, histochemical and morphometrical findings are reported. These findings are compared with 25 cases of pleural metastatic carcinoma and 25 cases of reactive pleural lesions.Fourty-nine percent of malignant mesotheliomas produced hyaluronic acid, however all cases of pleural metastatic carcinomas failed to produce this substance. All cases of malignant mesothelioma were D-PAS negative while 15 cases of pleural metastatic carcinoma showed reactivity to D-PAS. All cases of malignant mesothelioma and 9 cases of metastases were CEA negative.To distinguish malignant mesothelioma from metastases it is advisable to perform the D-PAS staining first. If it is negative mesothelioma can be confirmed by showing hyaluronic acid activity. A positive CEA staining rules out mesothelioma. In our study it was shown that with these methods 18 of 37 mesotheliomas could be identified with certainty, and 22 of the 25 carcinoma metastases.Morphometrically the malignant mesotheliomas could not be distinguished from the metastases, however the reactive pleural lesions had smaller nuclei than the malignant cells with mean values below 30 mu2. In the malignant cases these values had a range from 36 to 101 mu2.In distinguishing between reactive pleural lesions and malignant mesothelioma the production of hyaluronic acid points to the malignant character of the lesion.Thus histochemistry and immunostaining are important in the distinction of malignant mesothelioma from metastases, while the value of morphometry lies mainly in the separation of reactive lesions from malignant mesothelioma.  相似文献   
76.
The purpose of this study was to assess the V-(D)-J junctional region of the T cell receptor (TCR), the CDR3 region, which is responsible for glioma-specific antigen contact in αβ TCR-mediated recognition. We sequenced the TCR α and β chians of Vα7, and Vβ13.1 cDNA derived from tumor-infiltrating lymphocytes (TIL) of 12 glioma patients and also the corresponding clones from the patients' peripheral blood lymphocytes (PBL). A shared Vβ13.1 DJ sequence of the CDR3 region, NDβN, was demonstrated in 49 of 66 Vβ13.1+ clones (74.2 %) from the glioma TIL, whereas only 4 of 33 clones (12.1 %) were observed in the Vβ13.1+ clones from the PBL (p < 0.001). A common VDJ sequence, FCASS (Vβ13.1)-YRLPWGTSDS (NDβN)-GELFF(Jβ2.2), was observed not only in the gliomas from each patient, but also among all the patients with a preference for Vβ13.1. In contrast, the amino acid sequences of the Vβ13.1+ PBL clones were diverse and random. Next, we sequenced subclones from other Vβ subfamilies randomly selected to compare their VDJ region rearrangements (Vβ3 and Vβ5.1). In contrast to Vβ13.1, the amino acid sequences of these junctional regions were completely different in these subclones. The V-J junctional region of the α chain is dominated by a few clones in some patients, and no shared amino acid sequences were detected in the TCR Vα junctional region. However, in the Nα region of the Vα7-bearing TIL clones, arginine was used in 27 of 44 clones (61.4%) compared to only 3 of 12 clones from the PBL (p < 0.05). These results are consistent with the hypothesis that a clonal expansion/accumulation of glioma lineage-specific T cells occurred in vivo at the tumor site and that these T cells may be recognizing glioma-specific antigens.  相似文献   
77.
78.
This female patient was born in 1935 and died in 1976 with a malignant bone tumor involving the proximal humerus following multiple local recurrences, axillary lymph node metastases, and pulmonary metastases. Histologically, over the course of time, there was an increase in features of an atypical Ewing's sarcoma, at the expense of findings of a typical, extra-cranial so-called adamantinoma. In contrast to another report, our case showed neither epithelial nor endothelial features on fine structural examination, but rather primitive mesenchymal cells, as is described for Ewing's sarcomas.  相似文献   
79.
Summary The histological diagnosis of malignant mesothelioma of the pleura, especially the distinction from peripheral adenocarcinoma of the lung, may be difficult. The immunohistochemical reports previously published on this subject show diverging results mainly because a variety of antibodies and staining techniques have been used by the different authors. To obtain comparable and reproducible results standard techniques and commercialized antibodies should be applied in routine pathology. In order to investigate the value of immunohistochemistry for the separation of the two entities formalin fixed and paraffin embedded blocks of 47 mesotheliomas and 22 adenocarcinomas were investigated with the PAP technique and commercially available antibodies to carcino-embryonic antigen (CEA), keratin, vimentin, epithelial membrane antigen (EMA), pregnancy specific antigen (SP1), S-100 protein and monoclonal antibody lu-5 (mAB lu-5). CEA positivity was found in all 22 adenocarcinomas examined, but only 2/47 (4%) of all mesotheliomas showed a positive result. SP1 was positive in 13/22 (59%) of the adenocarcinomas, whereas only 3/47 (6%) mesotheliomas were positive for this marker. No significant difference in the rate of positive cases in the adenocarcinoma and mesothelioma group could be found with the other above mentioned antigens. The results of our study indicate that especially CEA, but also SP1 are valuable markers in the diagnosis of malignant mesothelioma.  相似文献   
80.
Summary Investigation of the behaviour of the renal Juxtaglomerular apparatus in 19 patients with malignant hypertension has shown that in kidneys fixed immediately after operation the Juxtaglomerular granulation index is twice as high as in autopsy kidneys. The formation of renin by the epitheloid cells begins with the appearance of osmiophilic substances in the region of the endoplasmic reticulum. The first stages of granule formation are small rhomboid particles in the Golgi cisternes, which aggregate to form bigger round or polymorphic granules in the Golgi area.In pathological conditions the substances synthesized may be set free and become active locally as a result of fibrinoid necrosis of the vascular wall. The rate of production is increased firstly by forcing rhe production of active agents in the preexistent epitheloid cells, secondly by transformation of the so-called bivalent cells and finally, by cell division.In accelerated hypertension the production of renin also takes place in nephrons whose glomeruli, tubules and macula densa, are damaged. There is a correlation between blood pressure elevation and the Juxtaglomerular granulation index.
Zusammenfassung Untersuchungen über das Verhalten des juxtaglomerulären Zellkomplexes der Niere bei 19 Patienten mit maligner Hypertonie haben folgendes ergeben: In operativ gewonnenen und sofort fixierten Nieren ist der juxtaglomeruläre Granulationsindex doppelt so hoch wie in Nieren aus dem Sektionsgut. Die Reninbildung der epitheloiden Zellen beginnt mit dem Auftreten osmiophiler Substanzen im Bereich des endoplasmatischen Reticulums. Kleine rhomboide Gebilde in Golgizisternen sind Vorstufen von reifen Sekretgranula, die sich im Golgifeld zu größeren runden oder vielgestaltigen Sekrettropfen zusammenlagern.Unter pathologischen Bedingungen können infolge fibrinoider Gefäß- wandnekrosen Sekretsubstanzen lokal frei und lokal wirksam werden. Vermehrte Arbeitsleistung erfolgt zunächst durch Forcierung der Sekretproduktion in den präexistenten epitheloiden Zellen, sodann durch Transformierung sogenannter bivalenter Zellen und schließlich durch Zellneubildungen.Reninproduktion findet bei akzelerierter Hypertonie auch in solchen Nephronen statt, deren Glomerula und Tubuli samt Macula densa strukturell geschädigt sind. Es besteht eine Korrelation zwischen Höhe des Blutdruckes und Höhe des Granulationsindex.
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