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61.
Samer Tohme Christof Kaltenmeier Patrick Bou-Samra Patrick R. Varley Allan Tsung 《Annals of surgical oncology》2018,25(12):3427-3435
Aim
To identify factors associated with refusal of surgery in patients with early-stage pancreatic cancer and estimate the impact of this decision on survival.Methods
Using the National Cancer Data Base, 26,358 patients were identified with potentially resectable tumors (pretreatment clinical stage I: T1 or T2 N0M0). Multivariate models were employed to identify factors predicting failure to undergo surgery and assess the impact on survival.Results
Of early-stage patients who were recommended surgery, 7.8% (N?=?992) refused surgery for resectable early-stage pancreatic cancer. On multivariable analysis, patients were more likely to refuse surgery if they were older [odds ratio (OR)?=?1.18; 95% confidence interval (CI) 1.16–1.19], female (OR?=?1.52; 95% CI 1.33–1.73), African American (vs White, OR?=?1.79; 95% CI 1.37–2.34), on Medicare/Medicaid (vs private, OR?=?2.75; 95% CI 1.54–4.92) or had higher Charlson–Deyo score (2 vs 0, OR?=?1.33; 95% CI 1.03–1.72). Patients were also significantly more likely to refuse surgery if they were seen at a center that is not an academic/research program (OR 1.9; 95% CI 1.6–2.27). Patients who were recommended surgery but refused had significantly worse survival than those with stage I who received surgery [median survival 6.8 vs 24 months, Cox hazard ratio (HR) 3.41; 95% CI 3.12–3.60].Conclusions
The percentage of patients refusing surgery for operable early-stage pancreatic cancer has been decreasing in the last decade but remains a significant issue that affects survival. Disparities in refusal of surgery are independently associated with several variables including gender, race, and insurance. To mitigate national disparities in surgical care, future studies should focus on exploring potential reasons for refusal and developing communication interventions.62.
Ronan P. Killeen Samer Arnous Ramon Martos Suhny Abbara Martin Quinn Jonathan D. Dodd 《European radiology》2010,20(8):1886-1895
Objective
To determine whether cardiac computed tomography (MDCT) can differentiate between functional and valvular aetiologies of chronic mitral regurgitation (MR) compared with echocardiography (TTE).Methods
Twenty-seven patients with functional or valvular MR diagnosed by TTE and 19 controls prospectively underwent cardiac MDCT. The morphological appearance of the mitral valve (MV) leaflets, MV geometry, MV leaflet angle, left ventricular (LV) sphericity and global/regional wall motion were analysed. The coronary arteries were evaluated for obstructive atherosclerosis.Results
All control and MR cases were correctly identified by MDCT. Significant differences were detected between valvular and control groups for anterior leaflet length (30?±?7 mm vs. 22?±?4 mm, P?<?0.02) and thickness (3.0?±?1 mm vs. 2.2?±?1 mm, P?<?0.01). High-grade coronary stenosis was detected in all patients with functional MR compared with no controls (P?<?0.001). Significant differences in those with/without MV prolapse were detected in MV tent area (?1.0?±?0.6 mm vs. 1.3?±?0.9 mm, P?<?0.0001) and MV tent height (?0.7?±?0.3 mm vs. 0.8?±?0.8 mm, P?<?0.0001). Posterior leaflet angle was significantly greater for functional MR (37.9?±?19.1° vs. 22.9?±?14°, P?<?0.018) and less for valvular MR (0.6?±?35.5° vs. 22.9?±?14°, P?<?0.017). Sensitivity, specificity, and positive and negative predictive values of MDCT were 100%, 95%, 96% and 100%.Conclusion
Cardiac MDCT allows the differentiation between functional and valvular causes of MR. 相似文献63.
Factors predicting tracer uptake in somatostatin receptor and MIBG scintigraphy of metastatic gastroenteropancreatic neuroendocrine tumors. 总被引:1,自引:0,他引:1
Samer Ezziddin Timur Logvinski Charlotte Yong-Hing Hojjat Ahmadzadehfar Hans-Peter Fischer Holger Palmedo Jan Bucerius Michael J Reinhardt Hans-Jürgen Biersack 《Journal of nuclear medicine》2006,47(2):223-233
Radiolabeled octreotide analogs (Oct) and metaiodobenzylguanidine (MIBG) offer 2 different approaches for imaging and targeting metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET). Despite successful establishment of the revised World Health Organization (WHO) classification, which distinguishes between low- and high-grade malignant GEP-NET, there is a lack of scintigraphic studies comparing uptake behavior on the basis of this categorization. This study aims to define predisposing factors of tracer uptake for both imaging principles implementing the updated tumor criteria of the current WHO classification. METHODS: Fifty-seven consecutive patients with histologically confirmed metastatic GEP-NET evaluated with both 111In-pentetreotide and 123I/131I-MIBG scintigraphy were included in this study. Intensity of tracer uptake was graded according to the different metastatic regions. Patients were classified as overall positive when avid uptake in the clinically relevant tumor lesions was present. Correlation was tested between the proportion of positive patients and tumor origin, function, and malignancy. RESULTS: Overall, 52 patients (91.2%) were Oct positive and 28 patients (49.1%) were MIBG positive. The proportion of tracer-positive patients was significantly higher (P < 0.05) in low-grade malignant tumors for both tracers and in functioning as well as in gastroenteral NET for MIBG. Five patients were negative for both tracers. None of the Oct-negative patients proved to be MIBG positive. CONCLUSION: Oct affinity is observed with high frequency throughout the subgroups of metastatic GEP-NET, whereas corresponding MIBG uptake is overall less prevalent and more group dependent. Tumor differentiation significantly impacts both Oct and MIBG uptake, whereas functionality predisposes only for MIBG accumulation. Though clearly inferior to Oct-based radioimaging in most GEP-NET, MIBG achieves a remarkable rate of radioligand accumulation in functioning midgut enterochromaffin cell metastases (>80% of patients positive). These results may have implications for patient management and potentially for selection and performance of targeted therapy. 相似文献
64.
Assessment of Osstell? and Periotest? systems in measuring dental implant stability (in vitro study)
Objectives
The objectives of this in vitro study were to investigate the sensitivity and reliability of the Osstell™ systems (Resonance Frequency Analysis – RFA) compared to the Periotest® system in implant bone simulated conditions. Three conditions were simulated: (1) the direct fixture-bone contact and fibrous tissue fixture contact, (2) The different levels of horizontal bone loss, and (3) The hardening implant–bone interface.Materials and methods
Forty-nine dental implant fixtures were placed in the center of acrylic cubes. In Part I seven fixtures were placed in direct contact with acrylic and another seven were placed in contact with polyvinyl siloxane impression material as soft interface. Part II: four sets of 0, 2, 4 and 6 mm horizontally exposed fixture samples were made (seven fixtures in each set). Part III: seven fixtures were placed in contact with a thin mix of autopolymerizing resin. The stability of these fixtures was measured using Osstell™ and Periotest® systems.Results
The mean Periotest® value(PTV) and Osstell™ measurements showed a significant difference between the direct contact and soft interface (P < 0.001). These values also showed statistically significant difference between the different levels of horizontally exposed fixture groups (P < 0.001). The level of horizontal fixture exposure was strongly correlated with the PTVS (r = 0.967) and strongly negatively correlated with Implant Stability Quotient (r = −0.946). A strong correlation was found between the Osstell™ readings and the change in the stiffness of the autopolymerizing resin fixture interface group (r = 0.986).Conclusions
Both Osstell™ and Periotest® systems proved to be sensitive in measuring dental implant stability in hard and in soft interfaces. Osstell™ also proved to be sensitive in detecting changes in the fixture interface stiffness. Osstell™ system proved to be more reliable compared to Periotest® system in measuring dental implant stability in hard and in soft interfaces. 相似文献65.
Deffieux X Raibaut P Rene-Corail P Katz R Perrigot M Ismael SS Thoumie P Amarenco G 《Neurourology and urodynamics》2006,25(7):782-787
AIMS: To assess whether the anal contraction during voluntary coughing is a simple spinal reflex-mediated activity or not. To address this question we studied the external intercostal (EIC) muscle activity and external anal sphincter (EAS) response to cough. MATERIALS AND METHODS: Electromyographic recordings were made from pre-gelled disposable surface electrodes. EAS electromyographic recordings were made from the EAS of the pelvic floor in 15 continent women all suffering from urgency and/or frequency without urge or stress urinary incontinence, and referred for urodynamic investigation. Electromyographic signal was immediately integrated (EMGi). The abdominal pressure was recorded with bladder and rectal pressure. EAS EMGi was recorded during successive voluntary cough. In three women, we have also recorded EIC EMGi activity since it is synchronous with diaphragmatic EMG activity during cough initiation. RESULTS: In all subjects, EAS EMGi activity precedes the onset of the abdominal pressure increase. The mean latency of EAS EMGi was 615 msec (+/-278). In the three subjects whose EMGi activity was recorded both on EAS and EIC, the onset of EAS EMGi activity occurred before the EIC EMGi activity (latency ranging from 40 to 780 msec) and before the increase in the abdominal pressure. CONCLUSIONS: The present study suggests that during coughing, EAS EMG activity increases before external intercostal muscle EMGi activity. The contraction of the EAS preceding the activation of muscles involved in coughing indicates that this response is not a result of a simple spinal reflex, but more likely the result of a more intricate reflex involving complex integrative centers. 相似文献
66.
Simon Pecha Tibor Ziegelhoeffer Yalin Yildirim Yeong-Hoon Choi Stephan Willems Hermann Reichenspurner Heiko Burger Samer Hakmi 《Interactive Cardiovascular and Thoracic Surgery》2021,32(3):402
OBJECTIVESTransvenous lead extraction using mechanical rotational- or laser sheaths is an established procedure. Lead dwell time has been recognized as a risk factor for extraction failure and procedure-related complications. We therefore investigated the safety and efficacy of transvenous extraction of leads with an implant duration of more than 10 years.Open in a separate windowMETHODSBetween January 2013 and March 2017, a total of 403 patients underwent lead extraction in 2 high-volume lead extraction centres. One hundred and fifty-four patients with extraction of at least 1 lead aged over 10 years were included in this analysis. Laser lead extraction was the primary extraction method, with additional use of mechanical rotational sheaths or femoral snares, if necessary. All procedural- and patient-based data were collected into a database and retrospectively analysed.RESULTSMean patient’s age was 65.8 ± 15.8 years, 68.2% were male. Three hundred and sixty-two leads had to be extracted. The mean lead dwell time of treated leads was 14.0 ± 6.1 years. Complete procedural success was achieved in 91.6% of cases, while clinical success was achieved in 96.8%. Failure of extraction occurred in 3.2%. Leads that could not be completely removed had a significantly longer lead dwell time (18.2 vs 13.2 years; P = 0.016). Additional mechanical rotational sheaths or femoral snares were used in 26 (16.9%) patients. Overall complication rate was 4.6%, including 5 (3.3%) major and 2 (1.3%) minor complications. There was no procedure-related mortality.CONCLUSIONSTransvenous lead extraction in leads aged over 10 years is safe and effective when performed in specialized centres and with use of multiple tools and techniques. Leads that could not be completely extracted had a statistically significant longer lead dwell time. 相似文献
67.
Walid Elmahdy Mohamed Osman Mohamed Farag Ahmad Shoaib Haisam Saad Keith Sullivan Unni Krishnan Samer Nashef Marius Berman 《Seminars in thoracic and cardiovascular surgery》2021,33(1):23-30
PPM was highly associated with long-term all-cause mortality. Small Aortic Valve Annulus MDT (SAVA-MDT) exploring options to prevent PPM, including the implantation of newer generation prosthetic valves, aortic root enlargement and TAVI, should be established. 相似文献
68.
Pernille Fevejle Cromhout Lau Caspar Thygesen Philip Moons Samer Nashef Sune Damgaard Selina Kikkenborg Berg 《Interactive Cardiovascular and Thoracic Surgery》2022,34(2):193
Open in a separate windowOBJECTIVESExisting risk prediction models in cardiac surgery stratify individuals based on their predicted risk, including only medical and physiological factors. However, the complex nature of risk assessment and the lack of parameters representing non-medical aspects of patients’ lives point towards the need for a broader paradigm in cardiac surgery. Objectives were to evaluate the predictive value of emotional and social factors on 4 outcomes; death within 90 days, prolonged stay in intensive care (≥72 h), prolonged hospital admission (≥10 days) and readmission within 90 days following cardiac surgery, as a supplement to traditional risk assessment by European System for Cardiac Operative Risk Evaluation (EuroSCORE).METHODSThe study included adults undergoing cardiac surgery in Denmark 2014–2017 including information on register-based socio-economic factors, and, in a nested subsample, self-reported symptoms of anxiety and depression. Logistic regression analyses were conducted, adjusted for EuroSCORE, of variables reflecting social and emotional factors.RESULTSAmongst 7874 included patients, lower educational level (odds ratio 1.33; 95% confidence interval 1.17–1.51) and living alone (1.25; 1.14–1.38) were associated with prolonged hospital admission after adjustment for EuroSCORE. Lower educational level was also associated with prolonged intensive care unit stay (1.27; 1.00–1.63). Having a high income was associated with decreased odds of prolonged hospital admission (0.78; 0.70–0.87). No associations or predictive value for symptoms of anxiety or depression were found on any outcomes.CONCLUSIONSSocial disparity is predictive of poor outcomes following cardiac surgery. Symptoms of anxiety and depression are frequent especially amongst patients with a high-risk profile according to EuroSCORE.Subj collection105, 123 相似文献
69.
Ahmad Samer Al-Homsi Zhongbin Lai Tara S. Roy M. Monzr Al-Malki Nicholas Kouttab Richard P. Junghans 《Transplant immunology》2014,30(1):40-45
Impairing dendritic cell (DC) function to prevent graft versus host disease (GvHD) is an appealing concept. DC antigen presentation is NF-κB pathway-dependent and bortezomib might therefore play a role in preventing alloreactivity. We obtained DC from the blood of patients enrolled in a phase I study using post-transplant cyclophosphamide and bortezomib for prevention of GvHD. Control samples were obtained from patients receiving standard GvHD prevention regimen. Pre-treatment samples were also collected from enrolled patients. DC isolated on days + 1, + 4, and + 7 showed progressive decrease in the expression of maturation markers in comparison to control. In a DC–CD4 + mixed lymphocyte reaction (MLR) where DC isolated from the recipient blood before graft infusion were the stimulator cells, T cell proliferation measured by bromodeoxyuridine (BrdU) integration was decreased in samples obtained on days + 14 and + 21 in comparison to control group. Finally, measured by real-time PCR, the expression of IκB progressively increased while the expression of NF-κB decreased in DC on days + 1, + 4, and + 7, in comparison to pre-treatment paired controls. We conclude that our data further justify exploring the role of bortezomib in GvHD prevention and propose a novel mechanism of action of bortezomib in DC. 相似文献
70.
Samer Samir Sayed Mahmoud Saurabh Odak Stephen Coogan Michael J. McNicholas 《International orthopaedics》2014,38(7):1489-1494