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101.
Functionally deficient mesenchymal stem cells reside in the bone marrow niche with M2‐macrophages and amyloid‐β protein adjacent to loose total joint implants 下载免费PDF全文
Bryan S. Margulies Sean D. DeBoyace Adrienne M. Parsons Connor G. Policastro Jessica S.S. Ee Timothy S. Damron 《Journal of orthopaedic research》2015,33(5):615-624
We sought to demonstrate whether there is a difference in the local mesenchymal stem cells (MSC) niche obtained from patients undergoing their first total joint replacement surgery versus those patients undergoing a revision surgery for an failing total joint implant. Bone marrow aspirates collected from patients undergoing revision total joint arthroplasty were observed to be less clonal and the expression of PDGFRα, CD51, ALCAM, endoglin, CXCL12, nestin, and nucleostemin were decreased. Revision MSC were also less able to commit to an osteoblast‐lineage or an adipocyte‐lineage. Further, in revision MSC, OPG, and IL6 expression were increased. Monocytes, derived from revision whole marrow aspirates, were less capable of differentiating into osteoclasts, the cells implicated in the pathologic degradation of bone. Osteoclasts were also not observed in tissue samples collected adjacent to the implants of revision patients; however, the alternatatively activated M2‐macrophage phenotype was observed in parallel with pathologic accumulations of amyloid‐β, τ‐protien and 3‐nitrotyrosine. Despite the limited numbers of patients examined, our data suggest that nucleostemin may be a useful functional marker for MSC while the observation of M2‐macrophage infiltration around the implant lays the foundation for future investigation into a novel mechanism that we propose is associated with loose total joint implants. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:615–624, 2014. 相似文献
102.
A non-human primate antiserum was prepared to acute lymphoblastic leukemia of T-cell phenotype (T-ALL) and, after absorptions with normal blood elements, reacted by immunofluorescence and microcytotoxicity to all the T-ALL tested. In addition, the antiserum reacted with cells from about 70% of the common ALL studied and immunoprecipitated the common ALL antigen of 100,000 daltons. However, when the anti-T-ALL serum was absorbed with with lymphoblasts from common ALL, it failed to react with common ALL lymphoblasts, yet reacted significantly with cells from patients with T-ALL phenotype and defined a 100,000-dalton membrane component not found on common ALL lymphoblasts. In addition, sequential immunoprecipitation of 125I-labeled T-ALL membranes by anti- common-ALL serum followed by anti-T-ALL serum detected the T-ALL membrane component of 100,000 daltons that was not found on common ALL. Thus, our results demonstrate the presence of of a unique human T-ALL antigen present on all T-ALL distinct from the common ALL antigen. 相似文献
103.
Comparative effectiveness of a bioengineered living cellular construct vs. a dehydrated human amniotic membrane allograft for the treatment of diabetic foot ulcers in a real world setting 下载免费PDF全文
Robert S. Kirsner MD PhD Michael L. Sabolinski MD Nathan B. Parsons RN BSN Michelle Skornicki MPH William A. Marston MD 《Wound repair and regeneration》2015,23(5):737-744
We evaluated the comparative effectiveness of a bioengineered living cellular construct (BLCC) and a dehydrated human amnion/chorion membrane allograft (dHACM) for the treatment of diabetic foot ulcers (DFUs). Using a wound care–specific electronic medical record database, we assessed real‐world outcomes in 218 patients with 226 DFUs receiving treatment in 2014 at 99 wound care centers. The analysis included DFUs ≥1 and <25 cm2 with duration <=1 year and area reduction ≤20% in 14 days prior to treatment (N=163, BLCC; N=63, dHACM). The average baseline areas and durations were 6.0 cm2 and 4.4 months for BLCC and 5.2 cm2 and 4.6 months for dHACM, respectively. Patients treated with dHACM had more applications compared to those treated with BLCC (median 3.0 vs. 2.0) (p=0.003). A Cox model adjusted for key covariates including area and duration found the median time to closure for BLCC was 13.3 weeks compared to 26 weeks for dHACM, and the proportion of wounds healed were significantly higher for BLCC by 12 weeks (48% vs. 28%) and 24 weeks (72% vs. 47%) (p=0.01). Treatment with a bioengineered living cellular technology increased the probability of healing by 97% compared with a dehydrated amniotic membrane (hazard ratio = 1.97 [95% confidence interval 1.17, 3.33], p=0.01). 相似文献
104.
作为标准化的非手术治疗,诱导化疗(ICT)在治疗局部晚期头颈鳞癌已有几十年的历史,但是关于其作用尚存争议。同期放化疗(CRT)是目前标准化的非手术治疗,然而由于ICT能够使肿瘤体积缩小,提高放疗的可行性,改善患者对放疗的耐受力,增加放疗后器官功能保留的可能性及降低远处转移率。所以,对ICT的研究从未停止。该文对近期随机试验进行回顾分析,与手术或单独CRT比较,评估ICT中紫杉醇的价值。Meta分析比较ICT中紫杉醇和顺铂及5氟尿嘧啶的作用。之前的随机试验中,并没有ICT提高生存率的报道。但 相似文献
105.
106.
107.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
108.
J Tang DJ Humes E Gemmil NT Welch SL Parsons JA Catton 《Annals of the Royal College of Surgeons of England》2013,95(5):323-328
Introduction
The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.Methods
Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.Results
There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).Conclusions
The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality. 相似文献109.
110.
Andrea M. Abbott MD MS Helen M. Parsons PhD MPH Todd M. Tuttle MD MS Eric H. Jensen MD 《Annals of surgical oncology》2013,20(1):139-147