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There are many different lower eyelid reconstruction techniques defined in the literature. Almost all of the published techniques have been described on elderly patients and use upper eyelid, periorbital or facial tissues as donor sites. However, in case of a paediatric patient or a young adult who has a crease-free and scarless face, camouflage of the facial donor-site scar is usually impossible. In order to avoid possible facial donor-site scars and upper eyelid deformities, a technique which uses the temporoparietal fascia (TPF) flap as the framework of a new eyelid was used for the reconstruction of an adolescent patient's postoncologic defect. The inner side of the flap was covered with nasal septal chondromucosal graft and the external side was covered with a retroauricular full-thickness skin graft. Eighteen months of unproblematic follow-up of this overlooked usage of the versatile TPF flap indicates that our technique has proved successful in terms of good functional and cosmetic outcome that is obtained at one stage.  相似文献   
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Previous studies have shown that nicotine increases the risk of necrosis in skin flaps. We investigated the effect of hyperbaric oxygen (HBO(2)) treatment on the survival of random skin flaps in nicotine-treated rats. Thirty-two Sprague-Dawley rats were divided into four groups with eight rats in each group. Group 1 (n=8) was the control, group 2 (n=8) received HBO(2) treatment without being exposed to nicotine, group 3 (n=8) received nicotine and group 4 (n=8) received HBO(2) treatment with exposure to nicotine. The rats in the nicotine-treated groups were prepared by treating them with nicotine for 28 days. At the end of the 28th day, standard McFarlane-type random skin flaps were lifted from the backs of all the rats. In groups 2 and 4, HBO(2) treatment started at the 30th min following the surgery and continued once a day for 7 days. The flap survival rates and histopathological evaluation results related to neovascularisation and granulation tissue formation were significantly better in the HBO(2)-treated groups (groups 2 and 4) than in the groups that did not receive HBO(2) treatment (groups 1 and 3) (p < 0.05). The flap survival rates, neovascularisation and granulation tissue formation were highest in group 2 and lowest in group 3 (p ≤ 0.001). No significant difference was observed between group 4, which received HBO(2) treatment with nicotine exposure, and the control group (group 1) (p > 0.05). In conclusion, our study demonstrates that HBO(2) treatment has a positive effect on flap survival in nicotine-treated rats.  相似文献   
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Leishmania braziliensis causes cutaneous (CL) and mucosal (ML) leishmaniasis. In the mouse, Fli1 was identified as a gene influencing enhanced wound healing and resistance to CL caused by Leishmania major. Polymorphism at FLI1 is associated with CL caused by L. braziliensis in humans, with an inverse association observed for ML disease. Here we extend the analysis to look at other wound healing genes, including CTGF, TGFB1, TGFBR1/2, SMADS 2/3/4/7 and FLII, all functionally linked along with FLI1 in the TGF beta pathway. Haplotype tagging single nucleotide polymorphisms (tag-SNPs) were genotyped using Taqman technology in 325 nuclear families (652 CL cases; 126 ML cases) from Brazil. Robust case-pseudocontrol (CPC) conditional logistic regression analysis showed associations between CL and SNPs at CTGF (SNP rs6918698; CC genotype; OR 1.67; 95%CI 1.10-2.54; P=0.016), TGFBR2 (rs1962859; OR 1.50; 95%CI 1.12-1.99; P=0.005), SMAD2 (rs1792658; OR 1.57; 95%CI 1.04-2.38; P=0.03), SMAD7 (rs4464148; AA genotype; OR 2.80; 95%CI 1.00-7.87; P=0.05) and FLII (rs2071242; OR 1.60; 95%CI 1.14-2.24; P=0.005), and between ML and SNPs at SMAD3 (rs1465841; OR 2.15; 95%CI 1.13-4.07; P=0.018) and SMAD7 (rs2337107; TT genotype; OR 3.70; 95%CI 1.27-10.7; P=0.016). Stepwise logistic regression analysis showed that all SNPs associated with CL at FLI1, CTGF, TGFBR2, and FLII showed independent effects from each other, but SNPs at SMAD2 and SMAD7 did not add independent effects to SNPs from other genes. These results suggest that TGFβ signalling via SMAD2 is important in directing events that contribute to CL, whereas signalling via SMAD3 is important in ML. Both are modulated by the inhibitory SMAD7 that acts upstream of SMAD2 and SMAD3 in this signalling pathway. Along with the published FLI1 association, these data further contribute to the hypothesis that wound healing processes are important determinants of pathology associated with cutaneous forms of leishmaniasis.  相似文献   
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Multidrug and extensively drug resistant Mycobacterium tuberculosis are a threat to tuberculosis control programs. Genotyping methods, such as spoligotyping and MIRU-VNTR typing (Mycobacterial Interspersed Repetitive Units), are useful in monitoring potentially epidemic strains and estimating strain phylogenetic lineages and/or genotypic families. M. tuberculosis Latin American Mediterranean (LAM) family is a major worldwide contributor to tuberculosis (TB). LAM specific molecular markers, Ag85C(103) single nucleotide polymorphism (SNP) and RD(Rio) long-sequence polymorphism (LSP), were used to characterize spoligotype signatures from 859 patient isolates from Portugal. LAM strains were found responsible for 57.7% of all tuberculosis cases. Strains with the RD(Rio) deletion (referred to as RD(Rio)) were estimated to represent 1/3 of all the strains and over 60% of the multidrug resistant (MDR) strains. The major spoligotype signature SIT20 belonging to the LAM1 RD(Rio) sublineage, represented close to 1/5th of all the strains, over 20% of which were MDR. Analysis of published datasets according to stipulated 12loci MIRU-VNTR RD(Rio) signatures revealed that 96.3% (129/134) of MDR and extensively drug resistant (XDR) clusters were RD(Rio). This is the first report associating the LAM RD(Rio) sublineage with MDR. These results are an important contribution to the monitoring of these strains with heightened transmission for future endeavors to arrest MDR-TB and XDR-TB.  相似文献   
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