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BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient.  相似文献   
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Entamoeba histolytica trophozoites produce amoebapores, a family of small amphipathic peptides capable of insertion into bacterial or eukaryotic membranes and causing cellular lysis. Recently, E. histolytica trophozoites that are totally deficient in the production of amoebapore-A were created through a gene silencing mechanism (R. Bracha, Y. Nuchamowitz, and D. Mirelman, Eukaryot. Cell 2:295-305, 2003). Here we tested the virulence of amoebapore A(-) trophozoites in models of the two major forms of amebic disease: amebic liver abscess and amebic colitis. We demonstrate that amoebapore expression is required for full virulence in the SCID mouse model of amebic liver abscess, but E. histolytica trophozoites that do not express amoebapore-A can still cause inflammation and tissue damage in infected human colonic xenografts. These data are consistent with the concept that tissue damage may proceed by different mechanisms in amebic liver abscess compared to amebic colitis.  相似文献   
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Constitutional mismatch repair deficiency is a rare cancer predisposition syndrome caused by biallelic mutations in one of the four mismatch repair genes. Patients are predisposed to various tumors including hematological malignancies, brain tumors and colorectal carcinomas. Phenotypic overlap with Neurofibromatosis-1 is well known, with most patients presenting with café-au-lait macules. Other common features include axillary and/or inguinal freckling and intracranial MRI foci of high T2W/FLAIR signal intensity similar to the typical FASI seen in Neurofibromatosis-1. In this cohort of eight patients with constitutional mismatch repair deficiency we describe overlapping phenotypical features with Tuberous Sclerosis complex. In addition to “ash-leaf like” hypomelanotic macules (five patients), we detected intracranial tuber-like lesions (three patients), renal cysts (three patients) and renal angiomyolipomas (two patients). All our patients also had Neurofibromatosis-1 like features, mainly café-au-lait macules. This study suggests that features of Tuberous sclerosis especially when overlapping with those of Neurofibromatosis 1 or malignancies atypical for these syndromes should raise the possibility of constitutional mismatch repair deficiency. Correct diagnosis is essential for appropriate genetic counseling and pre-emptive cancer surveillance.  相似文献   
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The role of different extracellular matrix (ECM)-degrading enzymesin the normal functioning of the placenta is well documented.Heparan sulphate proteoglycan (HSPG) is an integral constituentof the placental and decidual ECM. Because this proteoglycanspecifically interacts with various macromolecules in the ECM,its degradation may disassemble the matrix. Hence, in the caseof the placenta, this may facilitate normal placentation andtrophoblast invasion. Crude placental specimens were collectedfrom first and third trimester placentas. Heparanase (endo-P-glucuronidase)was isolated and purified by ammonium sulphate precipitationfollowed by sequential chromatographies on carboxymethyl-, heparin-and ConA-Sepharose columns. The placental enzyme was furthercharacterized for its molecular weight and specific inhibitionby heparin, and was shown to resemble heparanase expressed byhighly metastatic tumour cells and activated cells of the immunesystem. In order to locate the source of heparanase activityin the placenta, primary cytotrophoblast cultures were established.Intact cells, as well as conditioned medium and cell lysates,were analysed for heparanase activity using metabolically sulphate-labelledECM as a natural substrate. Heparanase was highly active inlysates of cytotrophoblasts. This activity was also expressedby intact cytotrophoblasts seeded on ECM, but no activity couldbe detected in the culture medium. Incubation of the cytotrophoblastsin contact with ECM resulted in release of ECM-bound basic fibroblastgrowth factor (bFGF). We propose that the cytotrophoblasticheparanase facilitates placentation, through cytotrophoblastextravasation and localized neovascularization. cytotrophoblast/extracellular matrix/heparanase/heparan sulphate proteoglycan/placenta  相似文献   
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A negative relationship between platelet monoamine oxidase (MAO) activity and Sensation Seeking (SS) has been reported in several studies. This study evaluates the possible contribution of autonomic nervous system (ANS) activity to this relationship. Additionally, confirmatory factor analysis was used to create models of ANS concepts from a larger number of psychophysiological variables. Skin conductance (SC) and heart rate (HR) were recorded from 46 men and 49 women during a two-session protocol that included rest periods, a balloon stress, a series of tones, and two tasks: two-flash threshold and tachistoscopic recognition. Results showed that the best-fitting models for both rest and task periods included concepts of SC base levels (“arousal”), SC lability, and HR, and were quite similar for men and women. MAO activity correlated positively with SC concepts, most strongly for women. Women showed negative relationships between sensation seeking and both SC arousal and HR concepts. In contrast, men showed evidence of positive relationships between SC concepts and an active life style. The sex differences and response specificity in these relationships make it unlikely that ANS activity mediates the negative MAO-SS relationship.  相似文献   
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We report a man who had the branchio-oto-renal (BOR) syndrome with crossed renal ectopia. His three children were born with bilateral renal agenesis and the so-called Potter syndrome. This case illustrates the potential severity of the renal anomalies in the BOR syndrome and the inadequacy of oligohydramnios and maternal serum alpha-fetoprotein as screening methods for renal agenesis. This case also implies strongly the necessity for meticulous search for renal anomalies in individuals with the BOR syndrome and proper counseling regarding the possibility of lethal bilateral renal agenesis.  相似文献   
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We report on three patients with duplication of distal 22q. One patient is a de novo carrier of the translocation t(21;22) (p13;q11), the other two are offspring of a translocation carrier t(10;22) (q26;q12). The clinical manifestations of these patients demonstrate the variability of the dup(22q) syndrome.  相似文献   
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We report a distinct type of spondyloepimetaphyseal dysplasia seen in 2 sibs and their second cousin, characterized by early onset severe short stature, small chest, and distended abdomen. They had short neck, severe lumbar lordosis, and marked genu varum due to fibular overgrowth and joint laxity. Radiographically, the patients had platyspondyly, initially noted during the first years of life, with central hypoplasia of the vertebral bodies. At a later age, the vertebrae appear squared with mild interpedicular narrowing. The long bone changes, which at early age resemble those seen in achondroplasia, later include general metaphyseal irregularities and significant epiphyseal ossification delay. These patients present a previously undescribed form of spondyloepimetaphyseal dysplasia, most probably transmitted as an autosomal recessive tract. © 1993 Wiley-Liss, Inc.  相似文献   
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