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401.
The spatial expression of mRNA for matrix metalloproteinase 2 (MMP-2), its putative activator, the membrane-type 1 matrix metalloproteinase (MT1-MMP), and the MMP-2 substrate type IV collagen was investigated in human placentas of both normal and tubal ectopic pregnancies and in cyclic endometrium using in-situ hybridization. Cytokeratin staining applied to adjacent sections was used to identify epithelial and trophoblast cells. In both normal and tubal pregnancies MT1-MMP, MMP-2 and type IV collagen mRNA were highly expressed and co-localized in the extravillous cytotrophoblasts of anchoring villi, in cytotrophoblasts that had penatrated into the placental bed and in cytotrophoblastic cell islands. In addition, the decidual cells of normal pregnancies in some areas co-expressed MT1-MMP and MMP-2 mRNA, with moderate signals for both components. Fibroblast-like stromal cells in tubal pregnancies were positive for MMP-2 mRNA but generally negative for MT1-MMP mRNA. The consistent co-localization of MT1-MMP with MMP-2 and type IV collagen in the same subset of cytotrophoblasts strongly suggests that all three components co-operate in the tightly regulated fetal invasion process. The co-expression of MT1-MMP and MMP-2 mRNA in some of the decidual cells indicates that these cells are also actively involved in the placentation process.   相似文献   
402.
Bacigaluppi S, Retta SF, Pileggi S, Fontanella M, Goitre L, Tassi L, La Camera A, Citterio A, Patrosso MC, Tredici G, Penco S. Genetic and cellular basis of cerebral cavernous malformations: implications for clinical management. Cerebral cavernous malformations (CCMs) are a diffuse cerebrovascular disease affecting approximately 0.5% of the population. A CCM is characterized by abnormally enlarged and leaky capillaries arranged in mulberry‐like structures with no clear flow pattern. The lesion might predispose to seizures, focal neurological deficits or fatal intracerebral hemorrhage. However, a CCM can also remain neurologically silent. It might either occur sporadically or as an inherited disorder with incomplete penetrance and variable expressivity. Due to advances in imaging techniques, the incidence of CCM diagnoses are increasing, and the patient must be managed on a multidisciplinary basis: genetic counselling, treatment if needed, and follow‐up. Advances have been made using radiological and pathological correlates of CCM lesions adding to the accumulated knowledge of this disease, although management of these patients is very variable among centers. This review is aimed at providing an update in genetic and molecular insights of this condition. Included are implications for genetic counselling, and possible approaches to prevention and treatment that derive from the understanding of pathogenetic mechanisms.  相似文献   
403.
Patients dying from primary intracranial malignancy are a potential source of organs for transplantation. However, a perceived risk of tumor transfer to the organ recipient has limited their use. We evaluated the risk of tumor transmission by reviewing the incidence in patients transplanted in the UK. Information from the UK Transplant Registry was combined with that from the national cancer registries of England, Wales and Northern Ireland to identify all organ donors between 1985 and 2001 inclusive with a primary intracranial malignancy and to identify the occurrence of posttransplant malignancy in the recipients of the organs transplanted. Of 11 799 organ donors in the study period, 179 were identified as having had a primary intracranial malignancy, including 33 with high‐grade malignancy (24 grade IV gliomas and 9 medulloblastomas). A total of 448 recipients of 495 organs from 177 of these donors were identified. No transmission of donor intracranial malignancy occurred. Organs from patients dying from primary intracranial malignancy, including those with high‐grade tumors, should be considered for transplantation and the small risk of tumor transmission should be balanced against the likely mortality for potential recipients who remain on the transplant waiting list.  相似文献   
404.
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