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991.
Fang FC Cheng YL Lee SC Chen JC Hsu HH Tzao C 《The Thoracic and cardiovascular surgeon》2008,56(5):283-286
BACKGROUND: Pectus excavatum (PE) repair by Nuss procedure is well established in pediatrics, but studies of adult female patients are rare. We analyzed the efficacy of the Nuss procedure in adult, female PE patients. METHODS: We retrospectively reviewed adult patients who underwent Nuss repair of PE from April 2005 to November 2007. Precise morphologic characterization of the pectus allowed an appropriate shaping of the bars to achieve a symmetric repair. RESULTS: Out of 126 consecutive adult patients who underwent the Nuss procedure at our institution, 15 women with a mean age of 24.6 +/- 4.01 years were enrolled in the study. Their preoperative Haller index had a mean of 5.72 +/- 2.38. Seven patients (46.67 %) underwent repair with the insertion of double pectus bars. Complications included transient bilateral pneumothorax (n = 1) and right-sided pleural effusion (n = 1). One patient received a subsequent breast augmentation, which yielded a better thoracic contour. CONCLUSIONS: The Nuss procedure offers a high satisfaction rate and an acceptable complication rate for PE repair in adult female patients. A subsequent surgery for breast augmentation can be considered after the Nuss repair has stabilized. 相似文献
992.
Bone microstructure and elastic tissue properties are reflected in QUS axial transmission measurements 总被引:1,自引:0,他引:1
Raum K Leguerney I Chandelier F Bossy E Talmant M Saïed A Peyrin F Laugier P 《Ultrasound in medicine & biology》2005,31(9):1225-1235
Accurate clinical interpretation of the sound velocity derived from axial transmission devices requires a detailed understanding of the propagation phenomena involved and of the bone factors that have an impact on measurements. In the low megahertz range, ultrasonic propagation in cortical bone depends on anisotropic elastic tissue properties, porosity and the cortical geometry (e.g., thickness). We investigated 10 human radius samples from a previous biaxial transmission study using a 50-MHz scanning acoustic microscope (SAM) and synchrotron radiation microcomputed tomography. The relationships between low-frequency axial transmission sound speed at 1 and 2 MHz, structural properties (cortical width Ct.Wi, porosity, Haversian canal density and material properties (acoustic impedance, mineral density) on site-matched cross-sections were investigated. Significant linear multivariate regression models (1 MHz: R(2) = 0.84, p < 10(-4), root-mean-square error (RMSE) = 38 m/s, 2 MHz: R(2) = 0.65, p < 10(-4), RMSE = 48 m/s) were found for the combination of Ct.Wi with porosity and impedance. A new model was derived that accounts for the nonlinear dispersion relation with Ct.Wi and predicts axial transmission velocities measured at different ultrasonic frequencies (R(2) = 0.69, p < 10(-4), RMSE = 52 m/s). 相似文献
993.
N Janel M Sarazin F Corlier H Corne L C de Souza L Hamelin A Aka J Lagarde H Blehaut V Hindié J-C Rain M L Arbones B Dubois M C Potier M Bottlaender J M Delabar 《Translational psychiatry》2014,4(8):e425
To determine whether apparent involvement of DYRK1A in Alzheimer''s disease (AD) pathology makes it a candidate plasma biomarker for diagnosis, we developed a method to quantify plasma DYRK1A by immunoblot in transgenic mouse models having different gene dosages of Dyrk1a, and, consequently, different relative protein expression. Then, we measured plasma DYRK1A levels in 26 patients with biologically confirmed AD and 25 controls (negative amyloid imaging available on 13). DYRK1A was detected in transgenic mouse brain and plasma samples, and relative levels of DYRK1A correlated with the gene copy number. In plasma from AD patients, DYRK1A levels were significantly lower compared with controls (P<0.0001). Results were similar when we compared AD patients with the subgroup of controls confirmed by negative amyloid imaging. In a subgroup of patients with early AD (CDR=0.5), lower DYRK1A expression was confirmed. In contrast, no difference was found in levels of DYRK1B, the closest relative of DYRK1A, between AD patients and controls. Further, AD patients exhibited a positive correlation between plasma DYRK1A levels and cerebrospinal fluid tau and phosphorylated-tau proteins, but no correlation with amyloid-β42 levels and Pittsburgh compound B cortical binding. DYRK1A levels detected in lymphoblastoid cell lines from AD patients were also lower when compared with cells from age-matched controls. These findings suggest that reduced DYRK1A expression might be a novel plasma risk factor for AD. 相似文献
994.
K. Zarca I. Durand-Zaleski C. Roux J-C. Souberbielle A-M. Schott T. Thomas P. Fardellone C-L. Benhamou 《Osteoporosis international》2014,25(6):1797-1806
Summary
We performed a cost-effectiveness analysis of four vitamin D supplementation strategies for primary prevention of hip fracture among the elderly population and found that the most cost-effective strategy was screening for vitamin D insufficiency followed by adequate treatment to attain a minimum 25(OH) serum level.Introduction
Vitamin D supplementation has a demonstrated ability to reduce the incidence of hip fractures. The efficiency of lifetime supplementation has not yet been assessed in the population over 65 years without previous hip fracture. The objective was to analyze the efficiency of various vitamin D supplementation strategies for that population.Methods
A Markov micro-simulation model was built with data extracted from published studies and from the French reimbursement schedule. Four vitamin D supplementation strategies were evaluated on our study population: (1) no treatment, (2) supplementation without any serum level check; (3) supplementation with a serum level check 3 months after initiation and subsequent treatment adaptation; (4) population screening for vitamin D insufficiency followed by treatment based on the vitamin D serum level.Results
“Treat, then check” and “screen and treat” were two cost-effective strategies and dominated “treat without check” with incremental cost-effectiveness ratios of €5,219/quality-adjusted life-years (QALY) and €9,104/QALY, respectively. The acceptability curves showed that over €6,000/QALY, the “screen and treat” strategy had the greatest probability of being cost-effective, and the “no treatment” strategy would never be cost-effective if society were willing to spend over €8,000/QALY. The sensitivity analysis showed that among all parameters varying within realistic ranges, the cost of vitamin D treatment had the greatest effect and yet remained below the WHO cost-effectiveness thresholds.Conclusions
Population screening for vitamin D insufficiency followed by treatment based on the vitamin D serum level is the most cost-effective strategy for preventing hip fracture occurrence in the population over 65 years old. 相似文献995.
Kim YT Park JC Choi SH Cho KS Im GI Kim BS Kim CS 《Journal of periodontal research》2012,47(4):514-524
Kim Y‐T, Park J‐C, Choi S‐H, Cho K‐S, Im G‐I, Kim B‐S, Kim C‐S. The dynamic healing profile of human periodontal ligament stem cells: histological and immunohistochemical analysis using an ectopic transplantation model. J Periodont Res 2012; 47: 514–524. © 2012 John Wiley & Sons A/S Background and Objective: Human periodontal ligament stem cells (hPDLSCs) have been reported to play the pivotal role in periodontal regeneration. However, the dynamic cellular healing process initiated by hPDLSCs still remains to be elucidated. In the present study, the sequence of regeneration by hPDLSCs was assessed using histological and immunohistochemical observation in an ectopic transplantation model, which is a well‐standardized assessment tool that excludes the innate healing factors from the animals. Material and Methods: Human periodontal ligament stem cells that were isolated and characterized from teeth (n = 12) extracted for the purpose of orthodontic treatment were transplanted with carriers into ectopic subcutaneous pouches in immunocompromised mice (n = 20). Animals were killed after several different healing periods: 3 d (n = 4), 1 (n = 4), 2 (n = 4), 4 (n = 4) and 8 wk (n = 4). Histological analysis for regenerated tissues formed by hPDLSCs was conducted using hematoxylin and eosin, Masson’s trichrome and picrosirius red staining. In addition, immunohistochemical staining was performed to observe the sequential expression of osteogenic/cementogenic and periodontal ligament tissue‐specific markers associated with periodontal regeneration. Results: The whole healing process by transplanted hPDLSCs could be broadly divided into four distinctive phases. In the first phase, proliferated hPDLSCs migrated evenly all over the carrier, and collagenous tissues appeared in the form of amorphous collagen matrices. In the second phase, collagen fibers were well arranged among the carriers, and cementoid‐like tissues were observed. In the third phase, the formation of mature collagen fibers, resembling Sharpey’s fibers, was associated with active mineralization of cementum‐like tissues, and in the fourth phase, the maturation of cementum‐like tissues was observed on carrier surfaces. Various osteogenic/cementogenic markers related to the regeneration processes were expressed in a well‐orchestrated time order. Interestingly, well‐organized cementum‐like and periodontal ligament fiber‐like tissues and cells with early and late osteogenic/cementogenic markers were frequently observed in the secluded area of carrier surfaces. We termed this area the cell‐rich zone. Conclusion: The results from this study clearly demonstrated the sequential histological changes during periodontal tissue regeneration by hPDLSCs. Understanding of this process would potentially enable us to develop better cell‐based treatment techniques. 相似文献
996.
Teare JA, Petit J‐C, Ripamonti U. Synergistic induction of periodontal tissue regeneration by binary application of human osteogenic protein‐1 and human transforming growth factor‐β 3 in Class II furcation defects of Papio ursinus. J Periodont Res 2012; 47: 336–344. © 2011 John Wiley & Sons A/S Background and Objective: Binary applications of recombinant human osteogenic protein‐1 (hOP‐1) and transforming growth factor‐β3 (hTGF‐β3) synergize to induce pronounced bone formation. To induce periodontal tissue regeneration, binary applications of hOP‐1 and hTGF‐β3 were implanted in Class II furcation defects of the Chacma baboon, Papio ursinus. Material and Methods: Defects were created bilaterally in the furcation of the first and second mandibular molars of three adult baboons. Single applications of 25 μg hOP‐1 and 75 μg hTGF‐β3 in Matrigel® matrix were compared with 20:1 binary applications, i.e. 25 μg hOP‐1 and 1.25 μg hTGF‐β3. Morcellated fragments of autogenous rectus abdominis striated muscle were added to binary applications. Sixty days after implantation, the animals were killed and the operated tissues harvested en bloc. Undecalcified sections were studied by light microscopy, and regenerated tissue was assessed by measuring volume and height of newly formed alveolar bone and cementum. Results: The hOP‐1 and hTGF‐β3 induced periodontal tissue regeneration and cementogenesis. Qualitative morphological analysis of binary applications showed clear evidence for considerable periodontal tissue regeneration. Quantitatively, the differences in the histomorphometric values did not reach statistical significance for the group size chosen for this primate study. The addition of morcellated muscle fragments did not enhance tissue regeneration. Binary applications showed rapid expansion of the newly formed bone against the root surfaces following fibrovascular tissue induction in the centre of the treated defects. Conclusion: Binary applications of hOP‐1and hTGF‐β3 in Matrigel® matrix in Class II furcation defects of P. ursinus induced substantial periodontal tissue regeneration, which was tempered, however, by the anatomy of the furcation defect model, which does not allow for the rapid growth and expansion of the synergistic induction of bone formation, particularly when additionally treated with responding myoblastic stem cells. 相似文献
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Vogel M Page E Boesecke C Reiberger T Schwarze-Zander C Mauss S Baumgarten A Wasmuth JC Nelson M Rockstroh JK;European AIDS Treatment Network 《Clinical infectious diseases》2012,54(4):556-559
Fibrosis progression after acute hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected patients with follow-up >9 months became similar to reported rates from studies in chronic HIV/HCV coinfection, as measured with transient elastometry. The duration of follow-up and serum alanine transaminase correlated with liver stiffness, and short follow-up resulted in high fibrosis progression rates. 相似文献