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81.
BACKGROUND: Perioperative hypothermia causes numerous severe complications, such as coagulopathy, surgical wound infections, and morbid myocardial outcomes. For prevention of intraoperative hypothermia, an inexpensive, non-disposable carbon fiber resistive warming system has been developed. METHODS: We evaluated the efficacy of resistive-heating, comparing to circulating-water mattress and forced-air warming system. Twenty four patients undergoing elective abdominal surgery were randomly assigned to warming with: 1) a circulating water mattress, 2) a lower-body forced-air system, or 3) a carbon-fiber, resistive-heating blanket. RESULTS: Tympanic membrane temperature in the first two hours of surgery decreased by 1.9 +/- 0.5 degrees C in the water mattress group, 1.0 +/- 0.6 degree C in the forced-air group, 0.8 +/- 0.2 degree C in the resistive-heating group. The decreases in core temperature by the end of surgery were 2.0 +/- 0.8 degrees C in the water mattress group, 0.6 +/- 1.1 degrees C in the forced-air group, and 0.5 +/- 0.4 degree C in the resistive blanket group, respectively. There was no significant difference in the changes of core temperature between the forced-air group and the resistive-heating group. No side effects related to resistive-heating blanket were observed. CONCLUSIONS: Even during major abdominal surgery, carbon-fiber resistive-heating maintains core temperature as effectively as forced air.  相似文献   
82.
Patients with porcelain aorta carry a high risk of cerebral as well as systemic embolism during cardiac surgery. Here we describe a case of severe aortic stenosis and coronary artery disease combined with the circumferentially calcified aorta. The patient was a 77-year-old man who successfully received four coronary artery bypass grafts with in situ arterial grafts without clamping the aorta and aortic valve replacement. Aortic valve replacement and two distal coronary artery anastomoses to the left circumflex artery and obtuse marginal branch were performed under cardiac arrest during hypothermic perfusion with endoaortic balloon occlusion, followed by partial endarterectomy and closure of the aorta buttressed with bovine pericardium under deep hypothermic circulatory arrest. While rewarming, the other two distal coronary anastomoses to the left anterior descending artery and diagonal branch were done on the beating heart in order to minimize cardiac arrest time. On-pump beating heart coronary artery bypass grafting (CABG) can be useful especially for combined complex cardiac surgery.  相似文献   
83.

Background

Mitral annular disjunction is a structural abnormality of the mitral annulus fibrosus and is pathologically defined by a separation between the atrial wall–mitral valve junction and the left ventricular attachment. Mitral annular disjunction can cause hypermobility of the mitral valve apparatus and is often associated with mitral valve prolapse (MVP). The aim of this study was to investigate the frequency and characteristics of mitral annular disjunction in the patients referred to an echocardiography laboratory and to compare these with previously reported pathological data.

Methods and results

We retrospectively studied 1439 patients (mean age 65 ± 17 years, 58% male) referred to our echocardiography laboratory from 6 January 2014 to 31 March 2014. The echocardiographic parameters were compared between the patients with and without mitral annular disjunction. There were 125 cases (8.7%) with mitral annular disjunction, of which 15 (12%) also had MVP. The number of MVP patients in the group with mitral annular disjunction was significantly larger than in the group without mitral annular disjunction (p < 0.0001). The grade of mitral regurgitation was not significantly different between the two groups.

Conclusions

Mitral annular disjunction was detected not only in patients with a myxomatous mitral valve but also in normal cases. The number of MVPs was significantly larger in patients with mitral annular disjunction than patients without mitral annular disjunction. Further investigation is needed to clarify the clinical significance of the mitral annular disjunction detected by routine echocardiography.
  相似文献   
84.

Background Context

For patients diagnosed with lumbar central canal stenosis with asymptomatic foraminal stenosis (FS), surgeons occasionally only decompress central stenosis and preserve asymptomatic FS. These surgeries have the potential risk of converting preoperative asymptomatic FS into symptomatic FS postoperatively by accelerating spinal degeneration, which requires reoperation. However, little is known about delayed-onset symptomatic FS postoperatively.

Purpose

This study aimed to evaluate the rate of reoperation for delayed-onset symptomatic FS after lumbar central canal decompression in patients with preoperative asymptomatic FS, and determine the predictive risk factors of those reoperations.

Study Design

This study is a retrospective cohort study.

Patient Sample

Two hundred eight consecutive patients undergoing posterior central decompression for lumbar canal stenosis between January 2009 and June 2014 were included in this study.

Outcome Measures

The number of patients who had preoperative FS and the reoperation rate for delayed-onset symptomatic FS at the index levels were the outcome measures.

Methods

Patients were divided into two groups with and without preoperative asymptomatic FS at the decompressed levels. The baseline characteristics and revision rates for delayed-onset symptomatic FS were compared between the two groups. Predictive risk factors for such reoperations were determined using multivariate logistic regression and receiver operating characteristics analyses.

Results

Preoperatively, 118 patients (56.7%) had asymptomatic FS. Of those, 18 patients (15.3%) underwent reoperation for delayed-onset symptomatic FS at a mean of 1.9 years after the initial surgery. Posterior slip in neutral position and posterior extension-neutral translation were significant risk factors for reoperation due to FS. The optimal cutoff values of posterior slip in neutral position and posterior extension-neutral translation for predicting the occurrence of such reoperations were both 1?mm; 66.7% of patients who met both of these cutoff values had undergone reoperation.

Conclusions

This study demonstrated that 15.3% of patients with preoperative asymptomatic FS underwent reoperation for delayed-onset symptomatic FS at the index levels at a mean of 1.9 years after central decompression, and preoperative retrolisthesis was a predictive risk factor for such a reoperation. These findings are valuable for establishing standards of appropriate treatment strategies in patients with lumbar central canal stenosis with asymptomatic FS.  相似文献   
85.
Because cardiomyocytes lose the ability to divide upon differentiation, myocardial failure is assumed to be generally irreversible. For terminal cardiac insufficiency, the potential for regenerative treatment by stem cells, especially embryonic stem (ES) cells, offers hope for the future. Recent studies showed that stem cells fuse spontaneously with cells remaining in damaged tissues, and restore tissue function. To imitate spontaneous fusion in vivo, we used polyethylene glycol (PEG) in vitro to fuse mouse ES cells and fetal cardiomyocytes and analyzed the cytochemical properties of the fused cells. Confocal laser scanning microscopy coupled with lipophilic dye labeling of the living cell membranes showed that there were fused cells of ES cells and cardiomyocytes after PEG treatment. By flow cytometry, the fusion efficiency between ES cells and cardiomyocytes was estimated to be about 45% of the total resulting cells. When green fluorescent protein (GFP)-expressing ES cells were fused with cardiomyocytes, the fused cells had immunoreactivity for GFP in their cytoplasm and cardiac troponin I in their myofibrils. Some of these cells also expressed proliferating cell nuclear antigen up to 11 days after fusion, the last time point examined. This study shows that PEG-induced fusions of mouse ES cells and cardiomyocytes have the cardiomyocyte phenotype and proliferation potential.  相似文献   
86.
Objectives: To evaluate the correlation between preoperatively predicted and pathologically measured prostate cancer volumes and to investigate the clinical use of preoperatively predicted cancer volume in predicting pathological stage. Methods: Correlations between pathological findings and various preoperative parameters, including the cancer volumes as predicted by using two methods (Vca and estimated PCvol), were analyzed in 196 patients who underwent radical prostatectomy for clinically localized prostate cancer. Results: Pathologically measured prostate cancer volume was significantly correlated with the Vca and estimated PCvol, but the correlation coefficients were respectively only 0.46 and 0.35. Prostate‐specific antigen (PSA), PSA density (PSAD), primary Gleason score, Vca, Vca fraction (Vcafx), and estimated PCvol were significantly higher in 82 patients with extraprostatic cancer than in 114 patients with organ‐confined cancer. Magnetic resonance imaging (MRI) findings were significantly correlated with pathological stage. Multivariate logistic regression analysis indicated that the Vcafx and MRI findings were significant predictors of extraprostatic cancer, but receiver operating characteristic analysis revealed that the combination of Vcafx and MRI findings had no advantage over the combination of Gleason score, PSAD, and MRI findings. Conclusions: Vca and estimated PCvol are significantly correlated with the pathologically measured cancer volume but their ability to accurately predict cancer volume is limited. Vcafx and MRI findings were statistically significant predictors of extraprostatic cancer but their combination was not superior to the combination of Gleason score, PSAD, and MRI findings.  相似文献   
87.
Several recent studies have demonstrated that the slit diaphragm of the glomerular epithelial cell (podocyte) is the structure likely to be the principal barrier in the glomerular capillary wall. Nephrin identified as a gene product mutated in congenital nephrotic syndrome located at the outer leaflet of plasma membranes of the slit diaphragm. The anti-nephrin antibody is capable of inducing massive proteinuria, which indicates that nephrin is a key functional molecule in the slit diaphragm. Expression of nephrin was reduced in glomeruli of minimal change nephrotic syndrome. Some recent studies demonstrated that podocin, CD2-associated protein and NEPH1 are also functional molecules in the slit diaphragm, and their expressions are altered in membranous nephropathy and also in focal glomerulosclerosis. These observations suggested that the alteration of the molecular arrangement in the slit diaphragm is involved in the development of proteinuria in several kinds of glomerular diseases. Recent studies of our group have demonstrated that type 1 receptor-mediated angiotensin II action reduced the expression of the slit diaphragm-associated molecules and that type 1 receptor blockade ameliorated proteinuria by preventing the function of angiotensin II on the slit diaphragm. By the subtraction hybridization techniques using glomerular cDNA of normal and proteinuric rats, we detected that synaptic vesicle protein 2B and ephrin B1 are involved in the maintenance of the barrier function of the slit diaphragm. Presented at the 36th Eastern Regional Meeting of the Japanese Society of Nephrology.  相似文献   
88.
Tetranectin was originally purified from human serum on the basis of plasminogen kringle 4-binding properties. Tetranectin enhances plasminogen activation by a tissue-type plasminogen activator so that it has been suggested to play a role in tissue remodeling. We have generated mice with a targeted disruption of the tetranectin gene to elucidate the biological function of tetranectin. In this study, we showed that wound healing was markedly delayed in tetranectin-null mice compared with wild-type mice. A single full-thickness incision was made in the dorsal skin. By 14 days after the incision, the wounds fully healed in all wild-type mice based on the macroscopic closure; in contrast, the progress of wound healing in the tetranectin null mice appeared to be impaired. In histological analysis, wounds of wild-type mice showed complete reepithelialization and healed by 14 days after the incision. However, those of tetranectin-null mice never showed complete reepithelialization at 14 days. At 21 days after the injury, the wound healed and was covered with an epidermis. These results supported the fact that tetranectin may play a role in the wound healing process.  相似文献   
89.
Objective:   The management of lower urinary tract symptoms that persist after radical prostatectomy remains to be established. We investigated whether an α1-blocker, naftopidil, improves LUTS in patients ≥1 year after radical prostatectomy.
Methods:   A total of 29 male patients received 25 mg/day of naftopidil for the first week, then 75 mg/day for 4 weeks. The frequency-volume chart, international prostate symptom score and quality of life index (QOL) were examined before and at the end of the 5-week administration in all subjects.
Results:   Total international prostate symptom score (I-PSS) and I-PSS subtotals associated with voiding symptoms and storage symptoms were significantly decreased at 5 weeks compared with baseline ( P  < 0.001 each). QOL index was significantly improved with naftopidil for 5 weeks ( P  < 0.001). From analyses of the frequency-volume chart, mean and maximum volume/void were significantly increased ( P  < 0.05 each).
Conclusion:   Lower urinary tract symptoms detected in patients ≥1 year after radical prostatectomy were markedly improved with administration of naftopidil at 75 mg/day. These symptoms could represent a novel target for medical treatment by improved understanding of the symptom pathology in the near future.  相似文献   
90.
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