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81.
Georgios K. Triantafyllopoulos Vasileios G. Soranoglou Stavros G. Memtsoudis Thomas P. Sculco Lazaros A. Poultsides 《The Journal of arthroplasty》2018,33(4):1166-1170
Background
As periprosthetic joint infections (PJIs) can have tremendous health and socioeconomic implications, recognizing patients at risk before surgery is of great importance. Therefore, we sought to determine the rate of and risk factors for deep PJI in patients undergoing primary total hip arthroplasty (THA).Methods
Clinical characteristics of patients treated with primary THA between January 1999 and December 2013 were retrospectively reviewed. These included patient demographics, comorbidities (including the Charlson/Deyo comorbidity index), length of stay, primary diagnosis, total/allogeneic transfusion rate, and in-hospital complications, which were grouped into local and systemic (minor and major). We determined the overall deep PJI rate, as well as the rates for early-onset (occurring within 2 years after index surgery) and late-onset PJI (occurring more than 2 years after surgery). A Cox proportional hazards regression model was constructed to identify risk factors for developing deep PJI. Significance level was set at 0.05.Results
A deep PJI developed in 154 of 36,494 primary THAs (0.4%) during the study period. Early onset PJI was found in 122 patients (0.3%), whereas late PJI occurred in 32 patients (0.1%). Obesity, coronary artery disease, and pulmonary hypertension were identified as independent risk factors for deep PJI after primary THA.Conclusion
The rate of deep PJIs of the hip is relatively low, with the majority occurring within 2 years after THA. If the optimization of modifiable risk factors before THA can reduce the rate of this complication remains unknown, but should be attempted as part of good practice. 相似文献82.
Danielle Y. Ponzio Lazaros A. Poultsides Anthony Salvatore Yuo-yu Lee Stavros G. Memtsoudis Michael M. Alexiades 《The Journal of arthroplasty》2018,33(5):1421-1425.e1
Background
The direct anterior approach (DAA) offers the potential for less soft tissue insult, improved early recovery, and reduced dislocation rates. However, complications are associated with the DAA, particularly during the learning curve. We compare the DAA learning curve experience with the posterior approach regarding in-hospital complications and revision rate.Methods
We evaluated systemic and local in-hospital complications associated with primary unilateral cementless THAs from January 1, 2010 to December 31, 2012 in 4249 patients through a posterior approach and 289 patients through a DAA. All procedures were performed consecutively by high-volume surgeons who use a single approach in a nonselective manner. The DAA was performed by surgeon transitioning from the posterior approach, thus incorporating the learning curve. Demographics were comparable. Revision procedures were captured through a minimum 4-year follow-up. Analyses compared complication and revision rates.Results
The DAA group demonstrated shorter length of stay, procedure time, lower blood transfusion rate, and increased discharge to home rate. Local and major systemic in-hospital complications were rare and comparable between groups. The minor systemic complication rate was significantly greater for the posterior group (10.9% posterior vs 6.2% DAA, P < .05). Revision rate was significantly greater for the posterior group (2.7% posterior vs 0.7% DAA, P < .032). The incidence of revision for dislocation was 1.5% for the posterior approach vs 0.4% for the DAA.Conclusion
There was an increased rate of in-hospital minor systemic complications and overall revision, predominantly due to instability, after THA by the posterior approach, in comparison with the DAA. 相似文献83.
84.
目的:了解冠心病患者是否存在组织型纤溶酶原激活物(t-PA)及纤溶酶原激活抑制物Ⅰ(PAI-Ⅰ)功能紊乱,以及这两个指标与血脂、胰岛素抵抗的相关关系。方法:选择2004年1月至2006年1月于我院住院就诊的冠心病患者作为观察对象。按临床类型分为SAP组、UAP组、AMI组、OMI组,并设健康对照组。检测t-PA、PAI-Ⅰ、胰岛素敏感性指数(IAI)、胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白(LDL)等指标。结果:(1)健康对照组t-PA高于各型冠心病组(P<0.05),AMI组t-PA低于其余各型冠心病组(P<0.05);健康对照组PAI-Ⅰ低于各型冠心病组(P<0.05),AMI组PAI-Ⅰ高于其余各型冠心病(P<0.05)。(2)t-PA与IAI呈正相关,与TC、TG、LDL呈负相关;PAI-Ⅰ则与IAI呈负相关,与TC、TG、LDL呈正相关。(3)各病例组t-PA于治疗后有所升高,PAI-Ⅰ于治疗后有所下降(P<0.05)。结论:冠心病患者存在明显的纤溶功能紊乱,且以急性期为重,并且纤溶功能紊乱与胰岛素抵抗、血脂异常等因素有关。 相似文献
85.
Willemieke S. Tummers Sarah E. Miller Nutte T. Teraphongphom Adam Gomez Idan Steinberg David M. Huland Steve Hong Sri-Rajasekhar Kothapalli Alifia Hasan Robert Ertsey Bert A. Bonsing Alexander L. Vahrmeijer Rutger-Jan Swijnenburg Teri A. Longacre George A. Fisher Sanjiv S. Gambhir George A. Poultsides Eben L. Rosenthal 《Annals of surgical oncology》2018,25(7):1880-1888
Background
Operative management of pancreatic ductal adenocarcinoma (PDAC) is complicated by several key decisions during the procedure. Identification of metastatic disease at the outset and, when none is found, complete (R0) resection of primary tumor are key to optimizing clinical outcomes. The use of tumor-targeted molecular imaging, based on photoacoustic and fluorescence optical imaging, can provide crucial information to the surgeon. The first-in-human use of multimodality molecular imaging for intraoperative detection of pancreatic cancer is reported using cetuximab-IRDye800, a near-infrared fluorescent agent that binds to epidermal growth factor receptor.Methods
A dose-escalation study was performed to assess safety and feasibility of targeting and identifying PDAC in a tumor-specific manner using cetuximab-IRDye800 in patients undergoing surgical resection for pancreatic cancer. Patients received a loading dose of 100 mg of unlabeled cetuximab before infusion of cetuximab-IRDye800 (50 mg or 100 mg). Multi-instrument fluorescence imaging was performed throughout the surgery in addition to fluorescence and photoacoustic imaging ex vivo.Results
Seven patients with resectable pancreatic masses suspected to be PDAC were enrolled in this study. Fluorescence imaging successfully identified tumor with a significantly higher mean fluorescence intensity in the tumor (0.09?±?0.06) versus surrounding normal pancreatic tissue (0.02?±?0.01), and pancreatitis (0.04?±?0.01; p?<?0.001), with a sensitivity of 96.1% and specificity of 67.0%. The mean photoacoustic signal in the tumor site was 3.7-fold higher than surrounding tissue.Conclusions
The safety and feasibilty of intraoperative, tumor-specific detection of PDAC using cetuximab-IRDye800 with multimodal molecular imaging of the primary tumor and metastases was demonstrated.86.
87.
目的:观察转染癌基因的骨髓基质干细胞在体外分化情况,为肝细胞癌的细胞源研究提供实验依据。方法:实验于2003-05/2004-06在南方医科大学药理教研室实验室完成。①两步法获取大鼠肝细胞,梯度离心法分离大鼠骨髓基质干细胞。②单基因转染是单独将c-myc或K-ras癌基因瞬时转染大鼠骨髓基质干细胞,6孔培养板中培养,24h后荧光显微镜下观察骨髓基质干细胞转染结果。双基因转染步骤相同,只是将c-myc和K-ras癌基因同时转染大鼠骨髓基质干细胞。③c-myc癌基因转染组、K-ras癌基因转染组、双癌基因转染组常规培养,加入含体积分数为0.1胎牛血清的DMEM培养基,于37℃、体积分数为0.05的CO2孵箱培养,每24h半量更换培养液。④c-myc癌基因转染 肝细胞组、K-ras癌基因转染 肝细胞组、双癌基因转染 肝细胞组将已转染癌基因的骨髓基质干细胞,置于叠加的培养板半透膜的上方(细胞密度均为1×105个/cm2),再将肝细胞置于半透膜的下方(每孔细胞密度为3×105/cm2)进行共培养,其余步骤同常规培养。⑤通过反转录聚合酶式反应和细胞免疫组化检测骨髓基质干细胞分化情况。结果:①癌基因转染24h骨髓基质干细胞检测结果:单独转染c-myc或K-ras癌基因的细胞,其绿色荧光蛋白呈均匀一致分布;双基因转染的细胞,绿色荧光蛋白呈点片状分布。②各组骨髓基质干细胞向肿瘤细胞分化检测结果:c-myc癌基因转染组、K-ras癌基因转染组、双癌基因转染组的骨髓基质干细胞,均未向肿瘤细胞分化;c-myc癌基因转染 肝细胞组、K-ras癌基因转染 肝细胞组、双癌基因转染 肝细胞组的骨髓基质干细胞,均向肝细胞癌发展;空白对照组骨髓基质干细胞细胞均为阴性。此外,双癌基因转染 肝细胞组的骨髓基质干细胞分化增殖迅速,反转录聚合酶式反应和免疫组化检测发现,培养第7天出现甲胎蛋白表达,并迅速增加,而第7天出现的白蛋白和细胞角蛋白18表达迅速减弱,第14天消失。结论:转染癌基因的骨髓基质干细胞,在向肝细胞诱导的条件下,部分癌基因可以使干细胞分化为肝癌细胞;多癌基因转染时,更易于使干细胞分化为肝癌细胞。 相似文献
88.
Annexin V for flow cytometric detection of phosphatidylserine expression on B cells undergoing apoptosis 总被引:85,自引:19,他引:85
Koopman G; Reutelingsperger CP; Kuijten GA; Keehnen RM; Pals ST; van Oers MH 《Blood》1994,84(5):1415-1420
Apoptosis, or programmed cell death, is a general mechanism for removal of unwanted cells from the immune system. It is characterized by chromatin condensation, a reduction in cell volume, and endonuclease cleavage of DNA into oligonucleosomal length fragments. Apoptosis is also accompanied by a loss of membrane phospholipid asymmetry, resulting in the exposure of phosphatidylserine at the surface of the cell. Expression of phosphatidylserine at the cell surface plays an important role in the recognition and removal of apoptotic cells by macrophages. Here we describe a new method for the detection of apoptotic cells by flow cytometry, using the binding of fluorescein isothiocyanate-labeled annexin V to phosphatidylserine. When Burkitt lymphoma cell lines and freshly isolated germinal center B cells are cultured under apoptosis inducing conditions, all cells showing chromatin condensation strongly stain with annexin V, whereas normal cells are annexin V negative. Moreover, DNA fragmentation is only found in the annexin V-positive cells. The nonvital dye ethidium bromide was found to stain a subpopulation of the annexin V-positive apoptotic cells, increasing with time. Our results indicate that the phase in apoptosis that is characterized by chromatin condensation coincides with phosphatidylserine exposure. Importantly, it precedes membrane damage that might lead to release from the cells of enzymes that are harmful to the surrounding tissues. Annexin V may prove important in further unravelling the regulation of apoptosis. 相似文献
89.
Xu-Feng Zhang Fabio Bagante Qinyu Chen Eliza W. Beal Yi Lv Matthew Weiss Irinel Popescu Hugo P. Marques Luca Aldrighetti Shishir K. Maithel Carlo Pulitano Todd W. Bauer Feng Shen George A. Poultsides Olivier Soubrane Guillaume Martel B. Groot Koerkamp Alfredo Guglielmi Timothy M. Pawlik 《Surgery》2018,163(5):1114-1120
Background
Intrahepatic cholangiocarcinoma with hepatic hilus involvement has been either classified as intrahepatic cholangiocarcinoma or hilar cholangiocarcinoma. The present study aimed to investigate the clinicopathologic characteristics and short- and long-term outcomes after curative resection for hilar type intrahepatic cholangiocarcinoma in comparison with peripheral intrahepatic cholangiocarcinoma and hilar cholangiocarcinoma.Methods
A total of 912 patients with mass-forming peripheral intrahepatic cholangiocarcinoma, 101 patients with hilar type intrahepatic cholangiocarcinoma, and 159 patients with hilar cholangiocarcinoma undergoing curative resection from 2000 to 2015 were included from two multi-institutional databases. Clinicopathologic characteristics and short- and long-term outcomes were compared among the 3 groups.Results
Patients with hilar type intrahepatic cholangiocarcinoma had more aggressive tumor characteristics (eg, higher frequency of vascular invasion and lymph nodes metastasis) and experienced more extensive resections in comparison with either peripheral intrahepatic cholangiocarcinoma or hilar cholangiocarcinoma patients. The odds of lymphadenectomy and R0 resection rate among patients with hilar type intrahepatic cholangiocarcinoma were comparable with hilar cholangiocarcinoma patients, but higher than peripheral intrahepatic cholangiocarcinoma patients (lymphadenectomy incidence, 85.1% vs 42.5%, P?<?.001; R0 rate, 75.2% vs 88.8%, P?<?.001). After curative surgery, patients with hilar type intrahepatic cholangiocarcinoma experienced a higher rate of technical-related complications compared with peripheral intrahepatic cholangiocarcinoma patients. Of note, hilar type intrahepatic cholangiocarcinoma was associated with worse disease-specific survival and recurrence-free survival after curative resection versus peripheral intrahepatic cholangiocarcinoma (median disease-specific survival, 26.0 vs 54.0 months, P?<?.001; median recurrence-free survival, 13.0 vs 18.0 months, P?=?.021) and hilar cholangiocarcinoma (median disease-specific survival, 26.0 vs 49.0 months, P?=?.003; median recurrence-free survival, 13.0 vs 33.4 months, P?<?.001).Conclusion
Mass-forming intrahepatic cholangiocarcinoma with hepatic hilus involvement is a more aggressive type of cholangiocarcinoma, which showed distinct clinicopathologic characteristics, worse long-term outcomes after curative resection, in comparison with peripheral intrahepatic cholangiocarcinoma and hilar cholangiocarcinoma. 相似文献90.
Serologic test for syphilis as a surrogate marker for human immunodeficiency virus infection among United States blood donors 总被引:2,自引:0,他引:2
GA Herrera ; EM Lackritz ; RS Janssen ; VP Raimondi ; RY Dodd ; J Aberle-Grasse ; LR Petersen 《Transfusion》1997,37(8):836-840
BACKGROUND: This study evaluated the usefulness of the serologic test for syphilis (STS) in preventing the transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses, and human T- lymphotropic virus via the transfusion of seronegative, infectious window-period blood. STUDY DESIGN AND METHODS: Demographic and laboratory information on blood donations made between January 1992 and June 1994 in 18 American Red Cross regions was analyzed. It was assumed that the same proportion of HIV-positive and HIV-infectious window- period donations reacted on STS and were negative on other screening tests (hepatitis B and C viruses and human T-lymphotropic virus). This proportion multiplied by the estimated number of HIV-infectious window- period donations is the number of post-screening HIV-infectious donations removed by STS. RESULTS: Of 4,468,570 donations, 12,145 (0.27%) were STS positive and 377 (0.008%) were HIV positive. Among donations that were negative on other screening tests, STS-reactive donations were 12 times more likely to be HIV positive (odds ratio = 11.9; 95% CI = 5,26). However, of an estimated 13 infectious window- period donations, 0.2 would have been removed because of a reactive STS, at a cost of over $16 million. CONCLUSION: STS is a poor marker and a costly strategy for preventing post-screening HIV infections and other blood-borne diseases. 相似文献