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91.
The dataset obtained with 64-slice multidetector CT (MDCT) for coronary artery evaluation can be used to calculate important left ventricular (LV) volumetric parameters. We compared LV parameters derived by new, commercially available, fully automated software for MDCT (Syngo Circulation, Siemens, Germany) to cardiac magnetic resonance (CMR) as a reference standard. Twenty patients underwent CMR after completing a clinically indicated MDCT. Ejection fraction (EF), end-systolic volume (ESV), end-diastolic volume (EDV), stroke volume (SV), and myocardial mass (MM) for MDCT were obtained using automated software and were compared to CMR measurements, with papillary muscles (PMs) included in, or excluded from, the blood pool. The Pearson correlation coefficient (r) and Bland-Altman method were used to determine agreement between methods. When PMs were included in the blood pool, the correlation was excellent for EF (r = 0.92, p < 0.001), ESV (r = 0.86, p < 0.001), and EDV (r = 0.80, p < 0.001). When PMs were excluded from CMR, correlation was still very good for EF (r = 0.89, p < 0.001), ESV (r = 0.82, p < 0.001), and EDV (r = 0.82, p < 0.001). MDCT values for SV and MM showed a good correlation compared to both CMR methods. When PMs were included, the correlation was good for SV (r = 0.70, p < 0.001), and MM (r = 0.70, p < 0.001); when they were excluded, the correlation was less robust but still significant for SV (r = 0.71, p < 0.001) and MM (r = 0.73, p < 0.001). In conclusion, EF, ESV, and EDV obtained by MDCT using simple, automated software correlated very well with CMR; SV and MM showed good correlation. Automated analysis of volumetric parameters by MDCT can be reliably utilized for clinical purposes.  相似文献   
92.
Dystonia is a movement disorder characterized by involuntary muscle contractions resulting in abnormal postures. Although common in the clinic, the etiology of dystonia remains unclear. Most dystonias are idiopathic and are not associated with clear pathological brain abnormalities. Attempts to genetically model these dystonias in rodents have failed to replicate dystonic symptoms. This is at odds with the fact that rodents can exhibit dystonia. Because of this discrepancy, it is necessary to consider alternative approaches to generate phenotypically and genotypically faithful models of dystonia. Conditional knockout of dystonia-related genes is 1 technique that may prove useful for modeling genetic dystonias. Lentiviral-mediated small or short hairpin RNA (shRNA) knockdown of particular genes is another approach. Finally, in cases in which the function of a dystonia-related gene is well-known, pharmacological blockade of the protein product can be used. Such an approach was successfully implemented in the case of rapid-onset dystonia parkinsonism, DYT12. This (DYT12) is a hereditary dystonia caused by mutations in the α3 isoform of the sodium potassium adenosine triphosphatase (ATPase) pump (sodium pump), which partially hampers its physiological function. It was found that partial selective pharmacological block of the sodium pumps in the cerebellum and basal ganglia of mice recapitulates all of the salient features of DYT12, including dystonia and parkinsonism induced by stress. This DYT12 model is unique in that it faithfully replicates human symptoms of DYT12, while targeting the genetic cause of this disorder. Acute disruption of proteins implicated in dystonia may prove a generally fruitful method to model dystonia in rodents.  相似文献   
93.

Introduction

Periapical infections secondary to pulpal necrosis are associated with bacterial contamination of the pulp. Porphyromonas endodontalis, a gram-negative organism, is considered to be a pulpal pathogen. P. gingivalis is phylogenetically related to P. endodontalis and synthesizes several classes of novel complex lipids that possess biological activity, including the capacity to promote osteoclastogenesis and osteoclast activation. The purpose of this study was to extract and characterize constituent lipids of P. endodontalis and evaluate their capacity to promote proinflammatory secretory responses in the macrophage cell line, RAW 264.7, as well as their capacity to promote osteoclastogenesis and inhibit osteoblast activity.

Methods

Constituent lipids of both organisms were fractionated by high-performance liquid chromatography and were structurally characterized using electrospray mass spectrometry or electrospray-mass spectrometry/mass spectrometry. The virulence potential of P. endodontalis lipids was then compared with known biologically active lipids isolated from P. gingivalis.

Results

P. endodontalis total lipids were shown to promote tumor necrosis factor alpha secretion from RAW 264.7 cells, and the serine lipid fraction appeared to account for the majority of this effect. P. endodontalis lipid preparations also increased osteoclast formation from RAW 264.7 cells, but osteoblast differentiation in culture was inhibited and appeared to be dependent on Toll-like receptor 2 expression.

Conclusions

These effects underscore the importance of P. endodontalis lipids in promoting inflammatory and bone cell activation processes that could lead to periapical pathology.  相似文献   
94.
95.

Background

Historically, patients presenting acutely with paraesophageal hernia and requiring urgent operation demonstrated inferior outcomes compared to patients undergoing elective repair.

Methods

A prospective IRB-approved database was used to retrospectively review 570 consecutive patients undergoing paraesophageal hernia repair between 2000 and 2016.

Results

Thirty-eight patients presented acutely (6.7%) and 532 electively. Acute presentation was associated with increased age (74 vs. 69 years) but similar age-adjusted Charlson comorbidity scores. A history of chest pain, intrathoracic stomach ≥75%, and mesoaxial rotation were more common in acute presentations. Emergency surgery was required in three patients (8%), and 35 patients were managed in a staged approach with guided decompression prior to semi-elective surgery. Acute presentation was associated with an increased hospital stay (5 (2–13) days vs. 4 (1–27) days, p = 0.001). There was no difference in postoperative Clavien-Dindo severity scores. One patient in the elective group died, and the overall mortality was 0.2%.

Conclusion

Our findings suggest that a majority of patients presenting with acute paraesophageal hernia can undergo a staged approach instead of urgent surgery with comparable outcomes to elective operations in high-volume centers. We suggest elective repair for patients presenting with a history of chest pain, intrathoracic stomach ≥75%, and a mesoaxial rotation.
  相似文献   
96.

Purpose

The benefits of robotic-assisted radical cystectomy (RARC) are unclear, especially in patients with high-risk disease (pT3/T4). We evaluated pathological and postoperative outcomes of RARC versus open radical cystectomy (ORC) in these patients.

Methods

We identified bladder cancer patients treated with RARC or ORC from January 2010–August 2014. Clinicodemographic factors were examined for potential confounding. Our primary outcome of interest was positive soft-tissue surgical margins (STSMs). Secondary outcomes included post-operative complications and length of stay (LOS). We used logistic regression to define the association between clinical factors with outcomes of interest, focusing on patients with locally advanced disease.

Results

We identified 472 patients treated with ORC (407, 86.2 %) or RARC (65, 13.8 %) of which 215 (45.6 %) were high-risk cases based on advanced pathologic stage (pT3/4). RARC patients were more commonly men (96.9 vs. 73.2 %, p < 0.01), had better performance status (ECOG 0, 78.5 vs. 59.7 %, p = 0.031), and received less neoadjuvant chemotherapy (21.5 vs. 39.3 %, p = 0.006). Total (52.3 vs. 59.7 %, p = 0.26) and high-grade complication rates (13.8 vs. 19.7 %, p = 0.27) were similar, but median LOS was shorter after RARC (6 vs. 7 days, p < 0.01). On multivariate analysis, prior pelvic radiation (OR: 4.78, 95 % CI: 2.16–10.57), and advanced tumor stage (OR: 3.06, 95 % CI: 1.56–6.03) were independently associated with positive STSMs in high-risk patients but robotic surgical approach was not (OR: 0.81, 95 % CI: 0.29–2.30; p = 0.69).

Conclusion

RARC had similar short-term postoperative outcomes compared to ORC and did not compromise oncological control in patients with extravesical disease.
  相似文献   
97.
Doctor patient communication is the most important and an integral part of any treatment regimen. Properly carried out it has been shown to have a therapeutic effect equivalent to drugs. Despite being so important part of treatment it is more than often taken and carried out casually. Apart from apathy towards this practice, its omission in the medical study curriculum is an important factor. This study was carried in amongst the surgical residents of surgical departments of various medical colleges to assess the attitude of surgical residents towards patient doctor communication. A questionnaire was forwarded by mail and email and the response was assessed: The responses of the surgical residents from various residents from different medical colleges were similar. Most of the residents prefer inclusion of communication skill in medical education curriculum  相似文献   
98.
Exposure to cigarette smoke is emerging as an environmental risk factor for multiple sclerosis (MS). We investigated the possible association between environmental tobacco smoke, its cumulative exposure, and MS risk. We used data from the Iranian Multiple Sclerosis Registry to identify a case-control of 662 patients who had MS and a comparison group of 394 patients. Information regarding current smoking status, including the number of cigarettes smoked per day, duration, and smoking pack-years indicative of cumulative dose of tobacco smoked was obtained. We analyzed the incidence of MS among ever–smokers who had been smokers during their disease course and prior to disease onset in comparison with never–smokers who had never been exposed by calculating the odds ratio (OR) with a 95% confidence interval (CI) employing logistic regression. Of the 662 MS patients, there were 523 women (79.0%) and 139 men (21.0%), with a mean age of 31 ± 10.0 years at disease onset. The risk for MS was increased among ever–smokers (OR = 1.78, 95% CI = 1.22–2.59, p = 0.03) compared to never–smokers. As compared with never smokers, the OR for patients with 6–10 pack years was 2.91 for men (95% CI = 1.11–9.47, p = 0.03) and 1.69 for women (95% CI = 1.02–6.45, p = 0.04). Our results demonstrate that cigarette smoking is significantly associated with an increased risk for MS. The risk effects of smoking were more noticeable in male patients and at higher tobacco doses.  相似文献   
99.
100.
PURPOSE: To report the safety, technical success, and effectiveness of percutaneous radiofrequency (RF) ablation for renal tumors. MATERIALS AND METHODS: The authors retrospectively reviewed the medical records and imaging studies of 29 consecutive patients (18 men, 11 women; mean age, 65 +/- 2.62 years) with 30 renal tumors (mean diameter, 3.5 +/- 0.24 cm) who underwent percutaneous RF ablation at their institution from September 2001 to March 2004. All procedures were performed with computed tomography guidance with general anesthesia, and all patients were admitted to the hospital for overnight observation. Technical success, complications, and their management were recorded. Technique effectiveness was assessed by imaging and clinical follow up. RESULTS: Overall, 88 overlapping ablations were performed (mean, 2.6 +/- 0.16 ablations per tumor per session) in 34 sessions. There were four major complications (12%). Three patients had gross hematuria and urinary obstruction, all were successfully treated. One patient had persistent anterior abdominal wall weakness. There were also two minor complications (6%) without significant clinical sequelae. One patient had gross hematuria which resolved spontaneously, another patient had transient paresthesia of the anterior abdominal wall. There were no significant changes in renal function after RF ablation. The intent of RF ablation was eradication of the primary tumor in 27 patients and treatment of gross hematuria in the other two. Technical success was achieved in all cases. Follow-up images were available for 26 patients. The primary tumor was completely ablated in 23 of 24 patients (96%) in whom eradication of the primary tumor was attempted (follow up period: mean, 10 months, median 7 months). The two patients treated for hematuria remained asymptomatic for 6 and 27 months each. CONCLUSION: Percutaneous RF ablation for renal tumors is safe and well tolerated. High technical success rates are expected. Early reports of the technique's effectiveness are promising.  相似文献   
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