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排序方式: 共有602条查询结果,搜索用时 15 毫秒
111.
Justin van Loon Daniël Hoornenborg Harm M van der Vis Inger N Sierevelt Kim TM Opdam Gino MMJ Kerkhoffs Daniël Haverkamp 《World journal of orthopedics》2021,12(1):14
BACKGROUNDIn press-fit total hip arthroplasty (THA) ceramic-on-ceramic (CoC) bearings are a potential for overcoming the wear that is seen in ceramic-on-polyethylene (CoPE) bearings, and can lead to wear-induced osteolysis, resulting in loosening of the implant. However, CoC bearings show disadvantages as well, such as squeaking sounds and being more fragile, which can cause ceramic head or liner fracture. Because comparative long-term studies are limited, the objective of this study was to determine the long-term difference in wear, identify potential predictive factors for wear, investigate radiological findings such as osteolysis, and evaluate clinical functioning and complications between these bearings.AIMTo determine 10-year differences in wear, predictive factors for wear, and investigate radiological findings and clinical functioning between CoC and CoPE.METHODSThis observational prospective single-center cohort study with a 10-year follow-up includes a documented series of elective THAs. Primary outcome was wear measured by anteroposterior (AP) radiographs. Secondary outcomes were potential predictive factors for wear, complications during follow-up, Harris hip score (HHS), and radiological findings such as presence of radiolucency, osteolysis, atrophy, and hypertrophy around the cup. Due to the absence of wear in the CoC group, stratified analysis to identify risk factors for wear was only performed in the CoPE group by use of univariate linear regression analysis. HHS was expressed as a change from baseline and the association with bearing type was assessed by use of multivariate linear regression analysis, adjusted for potential confounders.RESULTSA total of 17 CoPE (63.0%) and 25 CoC (73.5%) cases were available for follow-up and showed a linear wear of respectively 0.130 mm/year (range 0.010; 0.350) and 0.000 mm/year (range 0.000; 0.005), which was significant (P < 0.001) between both groups. Wear always occurred in the cranial direction. Cup inclination was the only predictive factor for polyethylene (PE) wear. No dislocations, ceramic head, or liner fractures were seen. The HHS showed a mean change from baseline of 37.1 points (SD 18.5) in the CoPE group and 43.9 (SD 17.0) in the CoC group. This crude difference of 6.8 (range -5.2; 18.7) in favor of the CoC group was not significant (P = 0.26) and was not significant when adjusted for age, gender, and diagnosis either (P = 0.99). No significant differences in complications and radiological findings were seen between groups. CONCLUSIONCoC bearing shows lower wear rates compared to CoPE at 10-year follow-up with cup inclination as a predictive factor for wear and no differences in complications, HHS, and radiological findings. 相似文献
112.
Adenoviral-mediated gene transfer in wound healing: acute inflammatory response in human skin in the SCID mouse model. 总被引:2,自引:0,他引:2
K G Sylvester M Nesbit A Radu M Herlyn N S Adzick T M Crombleholme 《Wound repair and regeneration》2000,8(1):36-44
The use of an adenoviral vector as a means of therapeutic protein delivery for the treatment of impaired wound healing is a potentially effective application of current gene transfer techniques. This study was designed to investigate the ability of adenovirus to mediate gene transfer in healing wounds in human skin in vivo. The human skin/severe combined immunodeficient mouse chimera model was used to study both the response of human tissue to adenoviral infection and the nature of the acute inflammatory response. The effects of adenoviral infection and transgene expression on the rate and quality of human wound healing were then investigated. Cell- and species-specific monoclonal antibodies were used to characterize the resident skin cell types participating in wound repair, the inflammatory response, and the proliferative potential of adenovirus-treated compared to control skin. Our studies show that, following wounding, normal skin architecture is restored in the presence of adenoviral infection equivalent to noninfected controls. Despite an increased acute inflammatory response after adenovirus injection, no difference in the healing capabilities of wounded skin was observed, suggesting that adenovirus-mediated gene transfer for growth factor-mediated acceleration of wound healing may be feasible. 相似文献
113.
T M Crombleholme 《Wound repair and regeneration》2000,8(6):460-472
The application of gene transfer strategies to wound healing is not an obvious use of this technology until one considers the important role of cytokines and growth factors in the normal wound healing response. Several gene transfer strategies have been proposed, from in vitro retroviral-mediated gene transfer with autologous transplantation, to in vivo plasmid based gene transfer as retroviral gene transfer. The limitations of these approaches have been efficiency of gene transfer, transgene expression and biologic response. Adenoviral-mediated gene transfer in wound healing is a relatively new application of this vector. The advantage of the adenovirus as a gene transfer vector lies in its ability to transduce nondividing cells of all types at very high efficiency without integration into the host cell's genome. The disadvantage of adenovirus as a vector is the relatively short duration of transgene expression and the inflammatory response it elicits. In the setting of wound healing brief duration of high levels of transgene may be all that is necessary to favorably influence wound healing. Secondly, as wound healing is fundamentally an inflammatory response, the inflammation elicited by the adenovirus may not be detrimental as long as the transgene is a growth factor with significant vulnerary effects such as platelet-derived growth factor-B. This review summarizes the current state of adenoviral-mediated gene transfer in experimental models of impaired wound healing which have laid the groundwork for proposed phase I clinical trials of adenoviral-mediated gene transfer of platelet-derived growth factor-B in chronic venous leg ulcers and chronic nonhealing diabetic foot ulcers. Adenoviral-mediated gene transfer is a useful tool in the study of the role of specific cytokines and growth factors in normal and impaired wound healing. Adenoviral-mediated gene transfer may hold significant promise for clinical application as a means of efficient growth factor delivery in correcting impaired wound healing. 相似文献
114.
David J. Margolis MD PhD Ole Hoffstad MA Stephen Thom MD PhD Warren Bilker PhD Arturo R. Maldonado MD Robert M. Cohen MD Bruce J. Aronow PhD Timothy Crombleholme MD 《Wound repair and regeneration》2010,18(5):445-451
Diabetic foot ulcers (DFU) or lower extremity amputation (LEA) are complications of diabetes. In those with diabetes, angiotensin‐converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) are commonly used to prevent the progression of kidney disease. Recent studies have indicated that angiotensin may affect angiogenesis and wound repair. Our goal was to evaluate in those with diabetes the likelihood of developing a DFU or LEA among users of ACEi or ARB using a retrospective cohort design of general practices in the United Kingdom. We studied 40,342 individuals at least 35 years of age with diabetes who were first prescribed ACEi or ARB between 1995 and 2006. A total of 35,153 individuals were treated with ACEi, 12,437 individuals with ARB, and 7,310 both. The hazard ratio for DFU was 0.50 (95% confidence intervals: 0.43, 0.59), showing an increased risk of DFU for those using ACEi vs. ARB. The hazard ratio for LEA was 0.72 (0.48, 1.01). However, among those with lower extremity peripheral arterial disease the hazard ratio was 0.45 (0.22, 0.91) for the new onset of a LEA. In conclusion, among those with diabetes, exposure to ACEi as compared with ARB increases the risk of developing a DFU or LEA. 相似文献
115.
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117.
Yen K. Bui Lisa W. Howley Steven E. Ambrose Henry L. Galan Timothy M. Crombleholme Julia Drose 《The journal of maternal-fetal & neonatal medicine》2016,29(10):1536-1540
Objectives: “Heart sparing” refers to prominent antegrade fetal coronary artery (CA) blood flow readily visualized by color Doppler and is a harbinger of poor outcome in growth restricted fetus, but little is known of the features and presentation of heart sparing in normally grown fetuses. Our objective was to describe heart sparing effects in normally grown fetuses, and compare the presentation and outcome of heart sparing between fetuses with growth restriction and those who were normally grown.Methods: In a series of fetuses with prominent antegrade CA flow, we assessed Doppler flow profiles in the aortic isthmus, ductus venosus (DV), umbilical vein (UV), umbilical artery (UA) and middle cerebral artery (MCA). We calculated MCA and UA systolic/diastolic ratios and the cerebral placental ratio, and measured fetal biometry. We evaluated cardiac function using the myocardial performance index (MPI) and the cardiovascular profile score (CVPS).Results: Ten fetuses with heart sparing had normal DV flow at 24–36.6 (mean 30.9) weeks of gestation. Five had growth restriction (Group 1); 4/5 had normal MPI and CVPS, and one died. Five were normally grown (Group 2); 5/5 had elevated MPI and decreased CVPS, of these 2 died in utero and one died immediately after birth despite urgent delivery. Coronary arteries were normal after birth or autopsy.Conclusions: Heart sparing confers a poor prognosis in fetal growth restriction and in normally grown fetuses with cardiac dysfunction. We suggest CA flow be assessed in all high-risk fetuses. 相似文献
118.
Anna G. Euser Mariana L. Meyers Michael V. Zaretsky Timothy M. Crombleholme 《The journal of maternal-fetal & neonatal medicine》2016,29(19):3172-3177
Objective: To compare congenital pulmonary airway malformation (CPAM) volume to head circumference ratios (CVRs) determined by different imaging modalities and calculation techniques.Methods: Fetal thoracic lesion images by ultrasound (US) and magnetic resonance imaging (MRI) were retrospectively reviewed and the CVRs were calculated. The CVRUS was determined by the standard method. The CVRMRI was calculated from T2-weighted sequences (HASTE/SSH-TSE) in two ways, dimensional measurements analogous to US technique (MRI-D) and by using a MRI-software calculated volume (MRI-V). CVR values between methods were compared using Wilcoxon matched-pairs signed-rank testing, Bland–Altman analyses, and Spearman correlations.Results: Appropriate images were available to compare CVRUS to CVRMRI-D for 20 patients and CVRUS to CVRMRI-V for 18 patients. There were no significant differences in CVR values between modalities. By Bland–Altman analyses, the CVR measurements were largely within the limits of agreement: 18 of 20 for CVRMRI-D and 17 of 18 for CVRMRI-V, with a slight bias towards larger measurements by MRI.Conclusions: Though values varied between modalities for individual patients, there was no systematic difference in CVRs determined by US or MRI. Fetal prognostic category for CPAMs did not change based on MRI in any patient in this series. 相似文献
119.
Calvo-Garcia MA Kline-Fath BM Levitt MA Lim FY Linam LE Patel MN Kraus S Crombleholme TM Peña A 《Pediatric radiology》2011,41(9):1117-1128