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J Oral Pathol Med (2012) 41 : 119–123 Objective: ‘Field cancerization’ is an accepted model for oral carcinogenesis. So far, genetically altered fields have been just reported in the presence of carcinomas. This study assessed the distant mirror fields (MFs) of oral precancer by DNA high‐resolution flow cytometry (hr DNA‐FCM) and array‐Comparative Genomic Hybridization (a‐CGH). Methods: Five leukoplakias without dysplasia (OLs), seven dysplastic leukoplakias (DOLs), and 12 corresponding visually normal and non‐dysplastic MFs were analyzed. DNA aneuploidy (DNA Index, DI ≠ 1) was detected by hr DNA‐FCM on DAPI stained nuclei suspensions. The epithelial DNA aneuploid subclones were FCM‐sorted to obtain genomic DNA for a‐CGH. Results: Mirror fields, OLs, and DOLs showed increasing prevalence of DNA aneuploidy of, respectively, 8%, 20%, and 57%. The average number of chromosome aberrations (Ch‐Abs) was 2.8 in MFs, 3 in OLs, and 10.6 in DOLs. MFs relative to OLs and DOLs had average numbers of Ch‐Abs, respectively, of 1.8 and 3.6. Ch‐Abs were also observed in DNA diploid sublines, and often the same aberrations were observed in both MFs and corresponding OLs/DOLs. Conclusion: DNA aneuploidy and Ch‐Abs in MFs, the last ones being mainly gains, indicate an early onset of field effect in oral carcinogenesis.  相似文献   
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Polypoid melanoma represents a rare clinical variant of nodular melanoma skin cancer in which the tumor is connected to the skin by a pedicle, characterized by exophytic growth, ulceration, and young age at onset (20-39 years) with a special predilection for the back and with a survival rate at 5 years ranging from 32% to 42% as compared with 57% 5-year survival for nodular subtype and 77% for the superficial subtype. We present a case of a deeply pigmented polypoid melanoma arising on the face of a 77-year-old man. We performed a literature review to clarify its surgical management and prognosis.  相似文献   
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The identification of important amino acid substitutions associated with low survival in hematopoietic cell transplantation (HCT) is hampered by the large number of observed substitutions compared with the small number of patients available for analysis. Random forest analysis is designed to address these limitations. We studied 2107 HCT recipients with good or intermediate risk hematological malignancies to identify HLA class I amino acid substitutions associated with reduced survival at day 100 post transplant. Random forest analysis and traditional univariate and multivariate analyses were used. Random forest analysis identified amino acid substitutions in 33 positions that were associated with reduced 100 day survival, including HLA-A 9, 43, 62, 63, 76, 77, 95, 97, 114, 116, 152, 156, 166 and 167; HLA-B 97, 109, 116 and 156; and HLA-C 6, 9, 11, 14, 21, 66, 77, 80, 95, 97, 99, 116, 156, 163 and 173. In all 13 had been previously reported by other investigators using classical biostatistical approaches. Using the same data set, traditional multivariate logistic regression identified only five amino acid substitutions associated with lower day 100 survival. Random forest analysis is a novel statistical methodology for analysis of HLA mismatching and outcome studies, capable of identifying important amino acid substitutions missed by other methods.  相似文献   
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This study concerns the morphological differentiation between double outlet right ventricle (DORV) and aortic dextroposition (AD) defects, namely tetralogy of Fallot and Eisenmenger anomaly. Indeed, despite the similar condition in terms of sequential ventriculo‐arterial connections, DORV and AD are two distinct morphological entities. It is proposed that the borderline between these two groups of malformations is represented by the specific insertion of the infundibular septum into the left anterior cranial division of the septomarginal trabeculation (or septal band) occurring in ADs and lacking in DORV. Furthermore, the spiraliform versus straight parallel arrangement of the great arteries in the two groups of anomalies is emphasized as an additional and distinctive morphological feature. Emphasis is also given to the association of straight parallel great arteries conotruncal malformations, DORV and transposition of the great arteries, with the asplenia type of heterotaxy laterality defects. Within this context, the absence of subaortic ventricular septal defect and concomitantly of spiraliform great arteries in the asplenia group of heterotaxy anomalies, as detected by this study, further substantiates our belief of not mixing collectively the ADs with the DORV in clinico‐pathological diagnosis. Anat Rec, 296:559–563, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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AIM: To investigate the correlation between autoimmune thyroid diseases (ATDs) and the prevalence of Cag-A positive strains of Helicobacter pylori (H. pylori) in stool samples.METHODS: Authors investigated 112 consecutive Caucasian patients (48 females and 4 males with Graves’ disease and 54 females and 6 males with Hashimoto’s thyroiditis HT), at their first diagnosis of ATDs. Authors tested for H. pylori in stool samples using an amplified enzyme immunoassay and Cag-A in serum samples using an enzyme-linked immunoassay method (ELISA). The results were analyzed using the two-sided Fisher’s exact test and the respective odds ratio (OR) was calculated.RESULTS: A marked correlation was found between the presence of H. pylori (P ≤ 0.0001, OR 6.3) and, in particular, Cag-A positive strains (P ≤ 0.005, OR 5.3) in Graves’ disease, but not in Hashimoto’s thyroiditis, where authors found only a correlation with Cag-A strains (P ≤ 0.005, OR 8.73) but not when H. pylori was present.CONCLUSION: The marked correlation between H. pylori and Cag-A, found in ATDs, could be dependent on the different expression of adhesion molecules in the gastric mucosa.  相似文献   
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