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51.
Epithelial-mesenchymal cell transformation (EMT) is a critical process during development of the heart valves. Transition of endothelial cells into mesenchymal cells in the atrioventricular (AV) canal and the outflow tract regions of the heart form the cardiac cushions that eventually form the heart valves. Collagen gel invasion assay has aided in the identification of molecules that regulate EMT. Among those, transforming growth factor-beta (TGF-beta) ligands and receptors demonstrate a critical role during EMT. In the chick, TGF-beta ligands and some receptors have specific functions during EMT. TGF-beta2 mediates endothelial cell-cell activation and separation, and TGF-beta3 mediates cell invasion into the extracellular matrix. Receptors involved in the EMT process include TGF-beta receptor type II (TBRII), TBRIII, endoglin and the TBRI receptors, ALK2 and ALK5. In contrast, in the mouse model, TGF-beta2 is the only ligand involved in EMT. The TGF-beta2 null mouse has either increased EMT or a mesenchymal cell proliferation after EMT. However, functional studies of TGF-beta1 in vivo and in vitro showed that TGF-beta1 functions in the EMT of the mouse AV canal. Latent TGF-beta-binding protein (LTBP-1) and endoglin have a role in the EMT process. Therefore, TGF-betas mediate cardiac EMT in both embryonic species. Further studies will reveal the identification of ligand and receptor-specific activities. 相似文献
52.
Paola Cambiaso MD Stefania Galassi MD Melania Palmiero MD Angela Mastronuzzi MD Francesca Del Bufalo MD Rossella Capolino MD Antonella Cacchione MD Paola S. Buonuomo MD Michaela V. Gonfiantini MD Andrea Bartuli MD Marco Cappa MD Marina Macchiaiolo MD 《American journal of medical genetics. Part A》2017,173(9):2353-2358
53.
Valverde L Rosique M Köhnemann S Cardoso S García A Odriozola A Aznar JM Celorrio D Schuerenkamp M Zubizarreta J Davis MC Hampikian G Pfeiffer H de Pancorbo MM 《International journal of legal medicine》2012,126(2):293-298
Individuals of Basque origin migrated in large numbers to the Western USA in the second half of the nineteenth century, and the flow continued with less intensity during the last century. The European source population, that of the Basque Country, has long been a cultural and geographical isolate. Previous studies have demonstrated that Y-STR frequencies of Basques are different from those of other Spanish and European populations [1]. The Basque diaspora in the Western USA is a recent migration, but the founder effect and the incorporation of new American Y chromosomes into the paternal genetic pool of the Basque diaspora could have influenced its genetic structure and could thus have practical implications for forensic genetics. To check for genetic substructure among the European source and Basque diaspora populations and determine the most suitable population database for the Basque diaspora in the Western USA, we have analysed the haplotype distribution of 17 Y-STRs in both populations. We have found that the Basque diaspora in the Western USA largely conserve the Y chromosome lineage characteristic of the autochthonous European Basque population with no statistically significant differences. This implies that a common 17 Y-STR Basque population database could be used to calculate identification or kinship parameters regardless of whether the Basque individuals are from the European Basque Country or from the Basque diaspora in the Western USA. 相似文献
54.
Acute superior vena cava syndrome after insertion of implantable cardioverter defibrillator 总被引:1,自引:0,他引:1
Andrea Rossi Massimo Baravelli Paolo Cattaneo Melania Romano Giovanni Mariscalco Daniela Imperiale Maria Cristina Rossi Anna Picozzi Paola Dario Claudio Anza Annibale Sandro Montenero 《Journal of interventional cardiac electrophysiology》2008,23(3):247-249
We describe a rare case of superior vena cava syndrome that occurred a few hours after insertion of an implantable cardioverter defibrillator through the right subclavian vein in a patient with previous dual chamber DDD pacemaker. The patient was successfully treated with anticoagulant therapy showing a fast clinical and instrumental improvement. 相似文献
55.
We present the case of a 51 year old woman with a history of several years of non organ specific Systemic Lupus Erythematosus, who presented a toxic syndrome and adenopathy and cranial nerve affection. We carried out the differential diagnosis. We then described the case resolution and progression. 相似文献
56.
57.
Cutaneous ulcers associated with Hansen's disease have long been recognized as among the most indolent of all ulcers. We have successfully treated such ulcers with porcine xenograft, achieving healing in ulcers which had been present for as much as three decades. These results suggest that this regimen may be applicable to other cutaneous ulcers wherever skin is missing. The newly available antibacterial effects of silver-impregnated porcine xenografts should have the result of increasing the effectiveness of the treatment still further. 相似文献
58.
Clinical dose-volume histogram analysis in predicting radiation pneumonitis in Hodgkin's lymphoma 总被引:1,自引:0,他引:1
Koh ES Sun A Tran TH Tsang R Pintilie M Hodgson DC Wells W Heaton R Gospodarowicz MK 《International journal of radiation oncology, biology, physics》2006,66(1):223-228
PURPOSE: To quantify the incidence of radiation pneumonitis (RP) in a modern Hodgkin's lymphoma (HL) cohort, and to identify any clinically relevant parameters that may influence the risk of RP. METHODS AND MATERIALS: Between January 2003 and February 2005, 64 consecutive HL patients aged 18 years or older receiving radical mediastinal radiation therapy (RT) were retrospectively reviewed. Symptomatic cases of radiation pneumonitis were identified. Dose-volume histogram parameters, including V(13), V(20), V(30), and mean lung dose (MLD), were quantified. RESULTS: At a median follow-up of 2.1 years, the actuarial survival for all patients was 91% at 3 years. There were 2 (2/64) cases of Radiation Therapy Oncology Group (RTOG) Grade 2 RP (incidence 3.1%). Both index cases with corresponding V(20) values of 47.0% and 40.7% were located in the upper quartile (2/16 cases), defined by a V(20) value of > or =36%, an incidence of 12.5% (p = 0.03). Similarly for total MLD, both index cases with values of 17.6 Gy and 16.4 Gy, respectively, were located in the upper quartile defined by MLD > or =14.2 Gy, an incidence of 11.8% (2/17 cases, p = 0.02). CONCLUSIONS: Despite relatively high V(20) values in this study of HL patients, the incidence of RP was only 3%, lower compared with the lung cancer literature. We suggest the following clinically relevant parameters be considered in treatment plan assessment: a V(20) greater than 36% and an MLD greater than 14 Gy, over and above which the risk of RTOG Grade 2 or greater RP would be considered clinically significant. 相似文献
59.
60.
Caliumi C Cotesta D Petramala L Lorio M Salvati M Filetti S De Toma G D'Erasmo E Letizia C 《Tumori》2006,92(2):178-180
The case of a 50-year-old woman with cerebral meningioma and concomitant parathyroid adenoma and papillary thyroid carcinoma is presented. She complained of neurological symptoms characterized by right hemiparesis and dysarthria. Cerebral CT and MRI scans revealed a left voluminous frontal parasagittal lesion with the characteristics of a meningioma. Routine laboratory analysis revealed altered values of calcium-phosphorus metabolism. Intravenous infusion of saline solution at 0.9% of NaCl resulted in a reduction of serum ionized calcium. A left craniotomy was performed and a fibroblastic meningioma of 5 cm in diameter was removed. Even though the patient's clinical condition was good, a calcium-phosphorus metabolism test confirmed high plasma levels of ionized calcium and parathyroid hormone. Thyroid and parathyroid ultrasonography revealed multinodular goiter and a parathyroid lesion confirmed by 99mTc-TCO4 / 99mTc-MIBI scintigraphy. A left superior parathyroidectomy and total thyroidectomy were performed. Histological examination revealed a parathyroid adenoma and a small papillary carcinoma of 0.4 cm in the right thyroid lobe. As far as we know, this patient is the third case of meningioma associated with parathyroid adenoma and papillary thyroid carcinoma described in the literature. 相似文献