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1.
A patient with cerebral deep sinus thrombosis, which was not diagnosed on the first examination, is reported. A 46-year-old woman presented with headache and vomiting. Neurological examination and a brain computed tomography (CT) scan showed no obvious abnormal findings. The patient suffered disturbed consciousness on the day after the examination, and was admitted to our emergency centre. A CT scan and magnetic resonance imaging revealed an ischaemic lesion in the left basal ganglia, suggesting deep sinus occlusion. Anticoagulant therapy was administered. One day after admission, a CT scan showed a haematoma and severe brain swelling in the same region. Cerebral angiography demonstrated a straight sinus occlusion. Intracranial pressure was not controlled with hypothermia, and the patient died 25 days after admission. Review of the initial CT scan revealed subtle, early findings of deep venous thrombosis that were missed on first examination.  相似文献   
2.
To evaluate the malignancy of esophageal cancer, we made a statistical clinicopathological study on 66 patients resected with definite operative and histological findings. The cumulative 5-year survival rate was 26.1%. By Cox's proportional hazard model depth and lymph node metastases were the prognostic factors in "Guide Lines for the Clinical and Pathological Studies on Carcinoma of the Esophagus". New histological factors for quantity idea: 1) depth judged by presence of cancer cells before irradiation; 2) intramural spreading characteristics; 3) volume of tumor measuring the infiltrating area of each layer; 4) distribution of metastatic lymph nodes set up by anatomical restriction and surgical risk; 5) number of metastatic lymph nodes. By analyzing the interaction of these 5 factors, the depth was correlated with the volume and the intramural spreading characteristics. The lymph node metastases were correlated significantly with the volume but not with the depth. The depth and the distribution of metastatic lymph nodes influenced prognosis according to Cox's proportional hazard model. Estimated survival rates of these factors were fitted to actual survival rates respectively. Postsurgical survival and adjuvant therapy may be determined by histological factor analysis.  相似文献   
3.
Primary carcinosarcoma of the vagina is a very rare tumor, with only eight cases diagnosed as carcinosarcoma in the literature that we are aware of. We recently encountered a case of primary carcinosarcoma of the vagina in a 75-year-old woman. The patient had a history of hysterectomy and bilateral ovariectomy for uterine corpus cancer at 55 years of age. Recurrence of the cancer was suspected 17 years after the operation and irradiation therapy was performed, but the patient died 3 years after the recurrence. Autopsy revealed a mass lesion in the pelvic cavity that originated in the vagina. Histological examination showed that the tumor contained anaplastic carcinoma, rhabdomyosarcoma, leiomyosarcoma and chondrosarcoma components, and it was diagnosed as carcinosarcoma. The histological diagnosis of the uterine corpus cancer was well-differentiated adenocarcinoma, and there was no sarcomatous component. The carcinosarcoma occurred 17 years after the hysterectomy, and it was concluded to be a primary carcinosarcoma of the vagina. This is the first case of primary vaginal carcinosarcoma in which the epithelial and sarcomatous components were clearly identified histologically and immunohistochemically.  相似文献   
4.
To compare immunophenotypic and molecular features between Burkitt lymphoma (BL) and diffuse large B-cell lymphoma (DLBCL) with c-myc rearrangements (c-mycR DLBCL), we analyzed 18 cases of B-cell non-Hodgkin's lymphoma with c-mycR that were confirmed by chromosomal and/or Southern blotting analyses. The cases were histologically classified into 10 BLs and five DLBCLs. The remaining three cases could not be classified because of suboptimal quality of the surgical materials. BLs were from five adults and five children, whereas all DLBCLs were from adults. BLs were positive for CD20 (10/10 cases examined), CD10 (9/10), Bcl-2 (1/9), and Bcl-6 (10/10), whereas they were negative for CD3 (0/10) and EBV (0/8), by Epstein-Barr virus (EBV) EBER-1 RNA in situ hybridization. c-MycR DLBCLs were positive for CD20 (5/5), CD10 (2/5), Bcl-2 (3/4), and Bcl-6 (4/4), whereas none of them were positive for CD3 and EBV. A mean of MIB-1 index (MIB-1+ cells/neoplastic cells, %) of BLs (98.1%) was higher than that of c-mycR DLBCLs (66.3%; P <.0001). Somatic mutation of immunoglobulin heavy-chain gene variable region (VH gene) in BLs (four cases) ranged from 0.7 to 4.9% with an average value of 2.3%, whereas those in DLBCLs (three cases) from 8.2 to 32.0% with an average value of 17.0%. It is, therefore, concluded that a growth fraction of nearly 100%, as well as a monotonous proliferation of medium-sized cells and c-myc(R), should be of value in the diagnosis of BL, which is probably different from c-myc(R) DLBCL. In addition, CD10+, Bcl-2-, and low frequency of mutation of the VH gene could be helpful for the histologic distinction of BL from (c-mycR) DLBCL.  相似文献   
5.
To elucidate the mechanism that produces enormous molecular diversity in troponin T (TnT) of fast skeletal muscle, we determined the 5-half genomic sequence of the chicken fast muscle TnT gene. The sequence of ca. 16 kb included seven exons (exons 1, 2, 3, 4, w, 5, and 6), which have been reported previously and presumed by sequencing TnT cDNAs. Additionally we found six 15 nt and one 18 nt sequences in the region between exons 5 and 6 (i.e. the exon x region). They were encompassed by consensus splice donor and acceptor sites and preceded by putative branch sites, and designated herein as exons xa to xg. Our result shows that the sequence derived from exons x1, x2, and x3, the exons presumed previously by cDNA sequencing, is actually encoded by the seven exons xa to xg, establishing the precise gene structure in the exon x region. Based on our data, together with that on the 3-half genomic sequence of the quail fast muscle TnT gene, we conclude that the avian fast skeletal muscle TnT gene includes 27 exons, 16 of which are alternatively spliced.  相似文献   
6.
T-helper-1 (Th1) cytokines play an important role in Crohn's disease, and interleukin-12 (IL-12), which is composed of two subunits, p40 and p35, drives Th1 differentiation. In previous reports, IL-12 p40 was shown to prevent IL-12 from binding to the receptor. We demonstrate here the effect of IL-12 p40 overexpression in intestinal epithelia on enterocolitis mediated by Th1 cells in IL-10-deficient (IL-10(-/-)) mice on a C57BL/6J background. IL-10 deficient (IL-10(-/-))/T3b-IL-12 p40+ (IL-12 p40+) mice and IL-10(-/-)/T3b-IL-12 p40- (IL-12 p40-) mice were generated by crossing T3b-IL-12 p40 transgenic mice and IL-10(-/-) mice. At 8 weeks of age, IL-12 p40+ mice did not show any clinical manifestations of colitis. The colon length of IL-12 p40- mice became shorter than that of IL-12 p40+ mice. The histological score of IL-12 p40+ mice was lower. Interferon-gamma (IFN-gamma) production was suppressed in both the mesenteric lymph node cell culture and colon tissue culture of IL-12 p40+ mice. There was no significant difference in IL-4 production and tumor necrosis factor-alpha (TNF-alpha) production between the two groups. These results show that overexpression of IL-12 p40 in intestinal epithelia prevents enterocolitis in IL-10(-/-) mice by suppressing IFN-gamma production, and suggest a potential clinical application of IL-12 p40 for Crohn's disease. Furthermore, these results also suggest that local gene transduction in the intestinal epithelium may be a potent therapeutic approach for Crohn's disease.  相似文献   
7.
In many neurodegenerative diseases, the cytopathological hallmark is the presence of ubiquitylated inclusions consisting of insoluble protein aggregates. Lewy bodies in Parkinson's disease and dementia with Lewy bodies disease, glial cell inclusions in multiple system atrophy, and hyaline inclusions in amyotrophic lateral sclerosis (ALS) are representative of these inclusions. The elucidation of the components of these inclusions and the mechanisms underlying inclusion formation is important in uncovering the pathogenesis of these disorders. We hypothesized that Dorfin, a perinuclearly located E3 ubiquitin ligase, participates in the formation of ubiquitylated inclusions in a wide range of neurodegenerative diseases. Here, we report that affinity-purified anti-Dorfin antibody labeled ubiquitylated inclusions of Parkinson's disease, dementia with Lewy bodies disease, multiple system atrophy, and sporadic and familial ALS. A double-immunofluorescence study revealed that Dorfin shows a distribution pattern parallel to that of ubiquitin. Furthermore, by a filter trap assay, we detected that Dorfin is present in the ubiquitylated high-molecular weight structures derived from these diseases. These results suggest that Dorfin plays a crucial role in the formation of ubiquitylated inclusions of alpha-synucleinopathy and ALS. However, because we failed to show the direct binding of alpha-synuclein with Dorfin, future investigations into the binding partner(s) of Dorfin will be needed to deepen our understanding of the pathophysiology of alpha-synucleinopathy and ALS.  相似文献   
8.
PTEN is an important tumor suppressor gene. Hereditary mutation of PTEN causes tumor-susceptibility diseases such as Cowden disease. We used the Cre-loxP system to generate an endothelial cell-specific mutation of Pten (Tie2CrePten) in mice. Tie2CrePten(flox/+) mice displayed enhanced tumorigenesis due to an increase in angiogenesis driven by vascular growth factors. This effect was partially dependent on the PI3K subunits p85alpha and p110gamma. In vitro, Tie2CrePten(flox/+) endothelial cells showed enhanced proliferation/migration. Tie2CrePten(flox/flox) mice died before embryonic day 11.5 (E11.5) due to bleeding and cardiac failure caused by impaired recruitment of pericytes and vascular smooth muscle cells to blood vessels, and of cardiomyocytes to the endocardium. These phenotypes depend strongly on p110gamma rather than on p85alpha and were associated with decreased expression of Ang-1, VCAM-1, connexin 40, and ephrinB2 but increased expression of Ang-2, VEGF-A, VEGFR1, and VEGFR2. Pten is thus indispensable for normal cardiovascular morphogenesis and post-natal angiogenesis, including tumor angiogenesis.  相似文献   
9.
10.
BACKGROUND: Cultures of human endometrial tissue are useful for analysing the mechanisms underlying the menstrual cycle. However, long-term culture of endometrial tissue is difficult in vitro. Xenotransplantation of normal human endometrial tissue into immunodeficient mice could allow prolonged survival of the transplanted tissues. METHODS: Proliferative-phase endometrial tissue samples from three women were transplanted into the subcutaneous space of ovariectomized, immunodeficient, non-obese diabetic (NOD)/severe combined immunodeficiency (SCID)/gammaC(null) (NOG) mice. The mice were treated with 17beta-estradiol (E2) for the first 14 days after transplantation, followed by E2 plus progesterone for the next 14 days. The transplants were investigated morphologically and immunohistochemically at various times after implantation. RESULTS: The transplanted tissues contained large numbers of small glands, pseudostratification of the nuclei and dense stroma after treatment with E2 alone. After treatment with E2 plus progesterone, subnuclear vacuolation, luminal secretion and decidualization of the stroma were observed. When the hormone treatment ceased, tissue destruction occurred and the transplants returned to the proliferative phase. Lymphocytes were identified immunohistochemically: the numbers of CD56-positive and CD16-negative cells increased significantly in the stroma during the late secretory phase (day 28). CONCLUSIONS: Human endometrial tissue transplanted into NOG mice showed similar histological changes to eutopic endometrial tissue during treatment with sex steroid hormones for 1 month. Moreover, lymphocytes were produced in the transplanted human endometrial tissue. This system represents a new experimental model of the human endometrium in vivo.  相似文献   
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