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41.
We have evaluated the feasibility of a newly developed single‐use, magnetically levitated centrifugal blood pump, MedTech Mag‐Lev, in a 3‐week extracorporeal membrane oxygenation (ECMO) study in calves against a Medtronic Bio‐Pump BPX‐80. A heparin‐ and silicone‐coated polypropylene membrane oxygenator MERA NHP Excelung NSH‐R was employed as an oxygenator. Six healthy male Holstein calves with body weights of about 100 kg were divided into two groups, four in the MedTech group and two in the Bio‐Pump group. Under general anesthesia, the blood pump and oxygenator were inserted extracorporeally between the main pulmonary artery and the descending aorta via a fifth left thoracotomy. Postoperatively, both the pump and oxygen flow rates were controlled at 3 L/min. Heparin was continuously infused to maintain the activated clotting time at 200–240 s. All the MedTech ECMO calves completed the study duration. However, the Bio‐Pump ECMO calves were terminated on postoperative days 7 and 10 because of severe hemolysis and thrombus formation. At the start of the MedTech ECMO, the pressure drop across the oxygenator was about 25 mm Hg with the pump operated at 2800 rpm and delivering 3 L/min flow. The PO2 of the oxygenator outlet was higher than 400 mm Hg with the PCO2 below 45 mm Hg. Hemolysis and thrombus were not seen in the MedTech ECMO circuits (plasma‐free hemoglobin [PFH] < 5 mg/dL), while severe hemolysis (PFH > 20 mg/dL) and large thrombus were observed in the Bio‐Pump ECMO circuits. Plasma leakage from the oxygenator did not occur in any ECMO circuits. Three‐week cardiopulmonary support was performed successfully with the MedTech ECMO without circuit exchanges. The MedTech Mag‐Lev could help extend the durability of ECMO circuits by the improved biocompatible performances.  相似文献   
42.
Human six-transmembrane epithelial antigen of prostate4 (STEAP4), an ortholog of mouse tumor necrosis factor-α-induced adipose-related protein (TIARP), plays a role in tumor necrosis factor (TNF)-dependent arthritis models. However, its role in rheumatoid arthritis (RA) is still obscure. This study explored such a role for STEAP4. The expressions of STEAP4, TNFα, and IL-6 were compared in synovia of RA and osteoarthritis patients. STEAP4 induction was examined in TNFα-stimulated fibroblast-like synoviocytes (FLS) in vitro. FLS (with/without TNFα stimulation) were also analyzed for IL-6 expression after STEAP4 knockdown, using siRNA or transfection with STEAP4-plasmid DNA. IL-8, cell proliferation, and apoptosis were also evaluated in STEAP4-overexpressing FLS. The expression of STEAP4 in joints correlated with TNFα expression, specifically in RA synovium. In the cultured FLS, STEAP4 protein expression was augmented by TNFα activation, and localized in endosomal/lysosomal compartments. STEAP4 downregulation by siRNA enhanced the expression of IL-6 mRNA, while STEAP4 overexpression suppressed IL-6 and IL-8 expression, inhibited cell proliferation, and induced apoptosis via caspase-3. The results indicated that human STEAP4 is regulated by TNFα in synovium, where it controls IL-6 secretion and proliferation of FLS, suggesting that STEAP4 might potentially suppress the pathogenesis of TNFα-induced arthritis such as RA.  相似文献   
43.

Purpose

Postoperative atrial fibrillation/flutter (AF) is still the most common complication after cardiovascular surgery, and it is important to determine the risk factors in order to establish effective management for recent postoperative AF. This study investigated the clinical predictors of postoperative AF using a prospectively collected database.

Methods

A total of 418 patients underwent cardiovascular surgery and were enrolled in this study. The relationship between postoperative AF and perioperative factors was examined.

Results

Postoperative AF occurred in 134 patients (32.1 %). A univariate analysis showed that an older age, hypertension, perioperative transfusion, use of cardiopulmonary bypass and thoracic aortic surgery were significantly associated with postoperative AF. The incidence of fibrillation was 49.4 % (39/79) in patients having aortic surgery. A multivariate analysis revealed that an older age, transfusion, and aortic surgery were all independent predictors of postoperative AF.

Conclusions

An older age, transfusion, and aortic surgery are strong independent predictors of postoperative AF. These findings help to identify high-risk patients for AF after cardiovascular surgery. Careful perioperative management is required for older patients undergoing aortic surgery with cardiopulmonary bypass.  相似文献   
44.
Objective: This field study aimed to assess the noise reduction of hearing protection for individual workers, demonstrate the effectiveness of training on the level of protection achieved, and measure the time required to implement hearing protector fit testing in the workplace. Design: The National Institute for Occupational Safety and Health (NIOSH) conducted field studies in Louisiana and Texas to test the performance of HPD Well-Fit. Study sample: Fit tests were performed on 126 inspectors and engineers working in the offshore oil industry. Results: Workers were fit tested with the goal of achieving a 25-dB PAR. Less than half of the workers were achieving sufficient protection from their hearing protectors prior to NIOSH intervention and training; following re-fitting and re-training, over 85% of the workers achieved sufficient protection. Typical test times were 6–12?minutes. Conclusions: Fit testing of the workers’ earplugs identified those workers who were and were not achieving the desired level of protection. Recommendations for other hearing protection solutions were made for workers who could not achieve the target PAR. The study demonstrates the need for individual hearing protector fit testing and addresses some of the barriers to implementation.  相似文献   
45.
To establish an optimal categorization of cancer deposits without lymph node structure (extranodal cancer deposits [EX]) in a prognostic staging system, we analyzed 1,027 cases in which patients underwent potentially curative surgery for advanced colorectal adenocarcinoma. EX was classified as vascular invasion-type (VAS) or non-VAS.A total of 512 foci of EX were identified in 205 patients (20.0%), with VAS and non-VAS found in 68 and 182 patients, respectively. The hazard ratio for patients with nodal involvement was 3.6 and for patients with VAS and non-VAS, 2.5 and 4.7, respectively. Based on multivariate analysis of these 3 parameters, only nodal involvement and non-VAS were significant prognosticators. By using the Akaike information criterion, N staging was capable of predicting survival outcome with the highest accuracy when both nodal involvement and non-VAS were treated together as an N factor and VAS was treated as a T factor ("new categorization"). The clinical significance of the TNM grading system for colorectal cancer would be enhanced if we treat EX as a new categorization.  相似文献   
46.

Purpose

We investigated the association between reproductive history and mortality from all and major causes among Japanese women.

Methods

A large-scale population-based cohort study in Japan included 40,149 eligible women aged 40–69 years in 1990–1994. A total of 4788 deaths were reported during follow-up (average 20.9 years). A Cox proportional hazards regression model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CI) for all-cause and major causes of mortality, adjusting for potential confounders.

Results

Inverse associations with all-cause mortality were found in parous women (0.74 [0.67–0.82]), women with two or three births compared with a single birth (2 births: 0.88 [0.78–0.99]; 3 births: 0.83 [0.74–0.94]), parous women who breastfed (0.81 [0.75–0.87]), women who were older at menopause (0.88 [0.80–0.97]; p-trend: <0.01), and women who had a longer fertility span (0.85 [0.76–0.95]; p-trend: <0.01). A positive association was seen between all-cause mortality and later age at first birth (≥30 years) than early childbearing (≤22 years).

Conclusions

Our study suggests that parous, two or three births, breastfeeding, late age at menopause, and longer reproductive span are associated with lower risk of all-cause of mortality.  相似文献   
47.
48.
The complex anatomy of the sacrum makes surgical fracture fixation challenging. We developed statistical models to investigate sacral anatomy with special regard to trans‐sacral implant fixation. We used computed tomographies of 20 intact adult pelves to establish 3D statistical models: a surface model of the sacrum and the trans‐sacral corridor S1, including principal component analysis (PCA), and an averaged gray value model of the sacrum given in Hounsfield Units. PCA demonstrated large variability in sacral anatomy markedly affecting the diameters of the trans‐sacral corridors. The configuration of the sacral alae and the vertical position of the auricular surfaces were important determinants of the trans‐sacral corridor dimension on level S1. The statistical model of trans‐sacral corridor S1 including the adjacent parts of the iliac bones showed main variation in length; however, the diameter was the main criterion for the surgically available corridor. The averaged gray value model revealed a distinct pattern of bone mass distribution with lower density particularly in the sacral alae. These advanced 3D statistical models provide a thorough anatomical understanding demonstrating the impact of sacral anatomy on positioning trans‐sacral implants. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1543–1548, 2014.  相似文献   
49.
To overcome the problems associated with sheet- or film-type anti-adhesive materials, we developed a new type of anti-adhesive material, gelatin flakes. We made two types of gelatin flakes with or without thermal cross-linking, and preliminarily examined their basic properties and the anti-adhesive efficacy using a rodent adhesion model. Both types of the gelatin flakes rapidly turned into gel and tightly attached the injured surfaces, absorbing the moisture and blood, when applied onto the abraded sites of rats. In addition, these flakes could be sprayed into the desired area by compressed air through a device with a long, thin tube, which could be used in laparoscopic surgery. The anti-adhesive effects of both types of gelatin flakes were similar, and both types were significantly superior compared to the non-treated group. Although further investigations are necessary, the gelatin flakes have unique and useful properties and satisfactory anti-adhesive effects, which indicate that they may be applicable in laparoscopic surgery.  相似文献   
50.
We investigated the cross-sectional relationship between ankle brachial index and cardiovascular disease risk factors, including C-reactive protein (CRP), among Japanese elderly, a topic which has had little prior epidemiologic study. Our study population comprised 946 subjects aged at least 70 years in whom both CRP and ankle brachial index were measured. The participants were classified into a low (ankle brachial index<0.9) and normal ankle brachial index group. We found that current smoking, high-density lipoprotein cholesterol <40 mg/dl, a low body mass index (continuous variable), hypertension, diabetes and statin use were all significantly related to a lower ankle brachial index. Higher log-transformed CRP level was significantly related to a lower ankle brachial index after adjustment for the cardiovascular risk factors mentioned above (p <0.01). The odds ratios for low ankle brachial index compared to 0-1 risk factors were 5.79 (95% confidence interval [CI]: 2.99-11.20) for 2 risk factors and 17.45 (95% CI: 6.78-49.91) for 3 or more risk factors; independently of other risk factors, the odds ratio for CRP>1.0 mg/l was 2.10 (95% CI: 1.13-3.88) compared to lower CRP values. Thus, a high level of CRP is related to a low ankle brachial index among Japanese elderly as well as Western subjects. This is the first study to report the relationship between CRP and low ankle brachial index among Japanese elderly.  相似文献   
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