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31.
T. Vuorinen M. Kallajoki T. Hyypi? R. Vainionp?? 《International journal of experimental pathology》1989,70(4):395-403
Coxsackievirus B3 infection in mice was studied histopathologically, by virus isolation and by nucleic acid hybridization after intraperitoneal inoculation of the virus. Extensive viraemia was detected for 1-3 days post-infection. All mice developed necrotizing acute pancreatitis and focal myocarditis. Pancreatitis eventually lead to complete atrophy of the exocrine pancreas. However, the islets of Langerhans and pancreatic ducts remained morphologically intact. Virus could be demonstrated in pancreatic tissue for 1-5 days post-infection by in-situ and spot hybridization as well as by virus isolation. Virus was not detectable on days 7-22 post-infection suggesting an autodigestive aetiology in further destruction of the exocrine pancreas. The mouse model described here permits detailed analysis of viral and host factors in the pathogenesis of enterovirus infections. Since coxsackie B viruses have been proposed to be aetiological agents in human acute pancreatitis, the application of in-situ hybridization allows analysis of enteroviruses directly from pancreatic tissue of clinical routine specimens. 相似文献
32.
Galina Sanaksenaho Annika Mutanen Nimish Godbole Maria Hukkinen Laura Merras-Salmio Reetta Kivisaari Antti Kyrönlahti Marjut Pihlajoki Jouko Lohi Markku Heikinheimo Mikko P Pakarinen 《Journal of pediatric surgery》2021,56(5):966-974
BackgroundIntestinal adaptation has been extensively studied experimentally, but very limited data is available on human subjects. In this study we assessed intestinal adaption in humans with short bowel syndrome (SBS).MethodsWe comparatively evaluated mucosal hyperplasia, inflammation, barrier function and nutrient transport using histology, immunohistochemistry and qPCR for selected 52 key genes in duodenal biopsies obtained from children with SBS after weaning off parenteral nutrition (n = 33), and matched controls without intestinal pathology (n = 12). Small bowel dilatation was assessed from contrast small bowel series.ResultsDuodenal mucosa of SBS children showed increased histologic inflammation of lamina propria (p = 0.033) and mucosal mRNA expression of tumor necrosis factor (p = 0.027), transforming growth factor (TGF)-β2 (p = 0.006) and caveolin-1 (CAV1; p = 0.001). Villus height, crypt depth, enterocyte proliferation, apoptosis and expression of proliferation and nutrient transport genes remained unchanged. Pathologic small bowel dilatation reduced crypt depth (p = 0.045) and downregulated mRNA expression of interleukin (IL)-6 by three-fold (p = 0.008), while correlating negatively with IL6 (r = -0.609, p = 0.004). Loss of ileocecal valve (ICV) upregulated mRNA expression of toll-like receptor 4 (TLR4), TGF-β1, CAV1, several apoptosis regulating genes, and mRNA expression of zonulin (p < 0.05 for all).ConclusionsDespite successful adaptation to enteral autonomy, duodenal mucosa of SBS children displayed histologic and molecular signs of abnormal inflammation and regulation of epithelial permeability, whereas no structural or molecular signs of adaptive hyperplasia or enhanced nutrient transport were observed. Excessive dilatation of the remaining small bowel paralleled impaired duodenal crypt homeostasis, while absence of ICV modified regulation of mucosal inflammation, regeneration and permeability.Level of evidenceII 相似文献
33.
Topi Laaksonen Jani Puhakka Antti Stenroos Jussi Kosola Matti Ahonen Yrjn Nietosvaara 《Journal of children's orthopaedics》2021,15(1):63
PurposeCompletely displaced distal radius fractures in children have been traditionally reduced and immobilized with a cast or pin fixed. Cast immobilization leaving the fracture displaced in the bayonet position has been recently suggested as a non-invasive and effective treatment alternative. This is a pilot comparative study between reduction and no reduction.MethodsWe assessed subjective, functional and radiographic outcome after a minimum 2.5-year follow-up in 12 children under ten years of age who had sustained a completely displaced metaphyseal radius fracture, which had been immobilized leaving the fracture in an overriding position (shortening 3 mm to 9 mm). A total of 12 age-matched patients, whose similar fractures were reduced and pin fixed, were chosen for controls. ResultsAt follow-up none of the 24 patients had visible forearm deformity and the maximal angulation in radiographs was 5° Forearm and wrist movement was restored (< 10° of discrepancy) in all 24 patients. Grip strength ratio was normal in all but three surgically treated patients. All patients had returned to their previous activities. One operatively treated boy who was re-operated on reported of pain (visual analogue scale 2).ConclusionThe results of this study do not demonstrate the superiority of reduction and pin fixation over cast immobilization in the bayonet position of closed overriding distal metaphyseal radius fractures in children under ten years with normal neurovascular findings.Level of evidenceIII 相似文献
34.
Interdigitating dendritic cell tumor with breast and cervical lymph-node involvement: a case report and review of the literature 总被引:3,自引:0,他引:3
Uluoğlu O Akyürek N Uner A Coşkun U Ozdemir A Gökçora N 《Virchows Archiv : an international journal of pathology》2005,446(5):546-554
Interdigitating dendritic cell tumor (IDCT) is an extremely rare malignancy. It occurs primarily in lymph nodes, but extranodal involvement has also been reported. A 38-year-old woman with IDCT with breast and cervical lymph-node involvement is reported in this paper. To our knowledge, this is the first case of IDCT originating from the breast. In the breast and lymph node, the tumor displayed diffuse sheets, fascicles and storiform growth pattern. It was composed of oval to spindle cells with pale to eosinophilic cytoplasm, ill-defined cell outlines, oval nuclei with vesicular chromatin and prominent eosinophilic nucleoli. Mitotic activity was three per ten high-power fields. The neoplastic cells were intermingled with small mature lymphocytes and plasma cells. Immunohistochemical studies showed that the tumor cells were strongly and diffusely positive for vimentin, CD68, S-100 protein, CD45/leukocyte common antigen and fascin and focally positive for lysozyme, alpha-1 antitrypsin and CD4. Ki-67 labeling index was 10%. The patient was treated with combined therapeutic approaches, including surgery, radiotherapy and chemotherapy. IDCT has the potential for an aggressive clinical course. However, 32 months after the initial diagnosis, the patient is still alive and being followed with a stable tumor burden. 相似文献
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38.
A. G. Remacle A. No??l C. Duggan E. McDermott N. O'Higgins J. M. Foidart M. J. Duffy 《British journal of cancer》1998,77(6):926-931
Matrix metalloproteinases (MMPs) are zinc dependent endopeptidases implicated in cancer invasion and metastasis. Gelatin zymography was performed on 84 human breast carcinomas and seven normal breast tissues. The precursor form of MMP-2 (72 kDa) was found in 11 (12%) samples, while its two activated forms, i.e. 62 kDa and 59 kDa, were found in three (6%) and 34 (40%) samples respectively. In contrast to MMP-2, most of the samples (52%) contained MMP-9 in its precursor form. Using ELISA, MMP-1 levels were found in 12% of the samples while MMP-3 levels were found in only 2% of the samples. Levels of MMP-2, -3 and -9 correlated inversely with numbers of nodal metastases. Neither MMP-2 nor -9 levels were significantly related to patient outcome. However, patients with high levels of a 50-kDa gelatinase band after zymography had a significantly better survival than patients with low levels. This species was never observed in normal breast tissue. 相似文献
39.
C. Linder P. Bystr??m G. Engel G. Auer U. Aspenblad H. Strander S. Linder 《British journal of cancer》1998,77(6):941-945
We examined the localization of basic fibroblast growth factor (bFGF) in a series of human breast carcinomas using immunohistochemistry. Staining was observed in tumour cells in 15 out of 54 (28%) tumours and in the adjacent stroma in 34 out of 54 (63%) tumours examined. No correlation was observed between positive staining of these two compartments. The relationship between bFGF staining and expression of the metalloprotease stromelysin-3, and between bFGF and microvessel density, was examined. A statistically significant correlation (P < 0.003) was observed between bFGF staining of the stromal compartment and high expression of stromelysin-3 (ST-3; MMP-11) metalloprotease mRNA by stromal cells. In contrast, no correlation was observed between bFGF and intratumour microvessel density (IMD). These results raise the possibility that bFGF may be involved in the induction of stromelysin-3 mRNA expression in breast cancer stroma. 相似文献
40.
S. Roth P. Kristo A. Auranen M. Shayehgi S. Seal N. Collins R. Barfoot N. Rahman P. J. Klemi S. Gr??nman L. Sarantaus H. Nevanlinna R. Butzow A. Ashworth M. R. Stratton L. A. Aaltonen 《British journal of cancer》1998,77(8):1199-1202
Inherited susceptibility to ovarian cancer has been associated with germline defects at several loci. The major known ovarian cancer susceptibility gene is BRCA1 on chromosome 17q, which confers a risk of approximately 60% by the age of 70 years. Truncating mutations in BRCA2 on chromosome 13q also predispose to ovarian cancer, although they confer a lower risk than mutations in BRCA1. We have studied the molecular basis of ovarian cancer predisposition in a Finnish family with three affected sisters. Analysis of polymorphic markers provided evidence against linkage to BRCA1, but the sibship was consistent with linkage to BRCA2. Conformation-sensitive gel electrophoresis was used to screen the entire coding sequence of BRCA2. A G to A transition at nucleotide 8702 was observed, which is predicted to convert glycine 2901 to aspartate in the encoded protein. This sequence variant was not detected in 220 cancer-free Finnish control individuals, or in several hundred cancer families of many nationalities previously screened for BRCA2 mutations. Taken together with the fact that this amino acid residue and the surrounding region of BRCA2 is identical in mouse and chicken, the data suggest that this alteration is a disease-causing BRCA2 missense mutation. Previously published data indicate that the risks of breast and ovarian cancer conferred by BRCA2-truncating mutations varies with the position of the mutation in the gene. The missense mutation reported here suggests that the BRCA2 domain including and surrounding glycine 2901 may be more important in preventing neoplastic transformation in ovarian epithelium than in breast epithelium. 相似文献