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991.
992.
Surgery Today - Inflammatory biomarkers such as the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) are reportedly predictive of the...  相似文献   
993.
Osteoarthritis (OA) is a group of common, chronic, and painful inflammatory joint diseases. One important finding in OA patients is a remarkable decrease in the molecular weight of hyaluronic acid (HA) in the synovial fluid of affected joints. Therapeutic HA is available to patients in most parts of the world as a viscosupplementation product for the treatment of OA. Previous clinical reports show that high molecular weight HA (HMWHA) more effectively relieves pain than low molecular weight HA (LMWHA). However, the mechanism behind this finding remains unclear. In this study, we investigated whether a LMWHA (Low‐0.9 MDa) and two types of HMWHA (High‐1.9 MDa and 6 MDa) differentially affected chondroregulatory action. We tested this using ATDC5 cell, a murine chondrocytic cell line widely used in culture systems to study chondrogenic differentiation. We found that HMWHA, especially hylan G‐F 20 (High‐6 MDa), significantly induced aggrecan and proteoglycan accumulation, nodule formation, and mRNA expression of chondrogenic differentiation markers in a time‐ and dose‐dependent manner. In addition, we showed that HMWHA prevented TNF‐α induced inhibition of chondrogenic differentiation, with no effect on cell proliferation or viability. These results reveal that HMWHA significantly promotes chondrogenic differentiation of ATDC5 cells in vitro, and suggest that HMWHA plays a significant chondroregulatory role in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1619–1627, 2014.  相似文献   
994.
We compared the effect of a sclerostin antibody to that of a clinically relevant dose of parathyroid hormone (PTH) in a rat model for metaphyseal bone healing. Screws of steel or poly methyl methacrylate (PMMA) were inserted bilaterally into the proximal tibia of young male rats. During 4 weeks the animals then received injections of either phosphate buffered saline (control), sclerostin antibody (25 mg/kg, twice weekly) or PTH (5 µg/kg, daily). The healing response around the screws was then assessed by mechanical testing and X‐ray microtomography (µCT). To distinguish between effects on healing and general effects on the skeleton, other untraumatized bone sites and serum biomarkers were also assessed. After 4 weeks of treatment, PTH yielded a 48% increase in screw pull‐out force compared to control (p = 0.03), while the antibody had no significant effect. In contrast, the antibody increased femoral cortical and vertebral strength where PTH had no significant effect. µCT showed only slight changes that were statistically significant for the antibody mainly at cortical sites. The results suggest that a relatively low dose of PTH stimulates metaphyseal repair (screw fixation) specifically, whereas the sclerostin antibody has wide‐spread effects, mainly on cortical bone, with less influence on metaphyseal healing. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:471–476, 2014.  相似文献   
995.
Rotator cuff tears can cause irreversible changes (e.g., fibrosis) to the structure and function of the injured muscle(s). Fibrosis leads to increased muscle stiffness resulting in increased tension at the rotator cuff repair site. This tension influences repairability and healing potential in the clinical setting. However, the micro‐ and meso‐scale structural and molecular sources of these whole‐muscle mechanical changes are poorly understood. Here, single muscle fiber and fiber bundle passive mechanical testing was performed on rat supraspinatus and infraspinatus muscles with experimentally induced massive rotator cuff tears (Tenotomy) as well as massive tears with chemical denervation (Tenotomy + BTX) at 8 and 16 weeks post‐injury. Titin molecular weight, collagen content, and myosin heavy chain profiles were measured and correlated with mechanical variables. Single fiber stiffness was not different between controls and experimental groups. However, fiber bundle stiffness was significantly increased at 8 weeks in the Tenotomy + BTX group compared to Tenotomy or control groups. Many of the changes were resolved by 16 weeks. Only fiber bundle passive mechanics was weakly correlated with collagen content. These data suggest that tendon injury with concomitant neuromuscular compromise results in extra‐cellular matrix production and increases in stiffness of the muscle, potentially complicating subsequent attempts for surgical repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1111–1116, 2014.  相似文献   
996.
This is the first successful report of a laparoscope-assisted Hassab's operation for esophagogastric varices after living donor liver transplantation (LDLT). A 35-year-old man underwent LDLT using a right lobe graft as an aid for primary sclerosing cholangitis (PSC) in 2005. Follow-up endoscopic and computed tomography (CT) examinations showed esophagogastric varices with splenomegaly in 2009 that increased (esophageal varices [EV]: locus superior [Ls], moderator enlarged, beady varices [F2], medium in number and intermediate between localized and circumferential red color signs [RC2]; gastric varices [GV]: extension from the cardiac orifice to the fornix [Lg-cf], moderator enlarged, beady varices [F2], absent red color signs [RC0]). A portal venous flow to the esophagogastric varices through a large left gastric vein was also confirmed. Preoperative Child-Pugh was grade B and score was 9. Because these esophagogastric varices had a high risk of variceal bleeding, we proceeded with a laparoscope-assisted Hassab's operation. Operative time was 464 minutes. Blood loss was 1660 mL. A graft liver biopsy was also performed and recurrence of PSC was confirmed histologically. It was suggested that portal hypertension and esophagogastric varices were caused by recurrence of PSC. Postoperative complications were massive ascites and enteritis. Both of them were treated successfully. This patient was discharged on postoperative day 43. Follow-up endoscopic study showed improvement in the esophagogastric varices (esophageal varices [EV]: locus superior [Ls], no varicose appearance [F0], absent red color signs [RC0], gastric varices [GV]: adjacent to the cardiac orifice [Lg-c], no varicose appearance [F0], absent red color signs [RC0]) at 6 months after the operation. We also confirmed the improvement of esophagogastric varices by serial examinations of CT.  相似文献   
997.
998.
Bone strength is predominantly determined by bone density, but bone microarchitecture also plays an important role. We examined whether trabecular bone score (TBS) predicts the risk of vertebral fractures in a Japanese female cohort. Of 1950 randomly selected women aged 15 to 79 years, we analyzed data from 665 women aged 50 years and older, who completed the baseline study and at least one follow‐up survey over 10 years, and who had no conditions affecting bone metabolism. Each survey included spinal imaging by dual‐energy X‐ray absorptiometry (DXA) for vertebral fracture assessment and spine areal bone mineral density (aBMD) measurement. TBS was obtained from spine DXA scans archived in the baseline study. Incident vertebral fracture was determined when vertebral height was reduced by 20% or more and satisfied McCloskey‐Kanis criteria or Genant's grade 2 fracture at follow‐up. Among eligible women (mean age 64.1 ± 8.1 years), 92 suffered incident vertebral fractures (16.7/103 person‐years). These women were older with lower aBMD and TBS values relative to those without fractures. The unadjusted odds ratio of vertebral fractures for one standard deviation decrease in TBS was 1.98 (95% confidence interval [CI] 1.56, 2.51) and remained significant (1.64, 95% CI 1.25, 2.15) after adjusting for aBMD. The area under the receiver operating characteristic curve of TBS and aBMD combined was 0.700 for vertebral fracture prediction and was not significantly greater than that of aBMD alone (0.673). However, reclassification improvement measures indicated that TBS and aBMD combined significantly improved risk prediction accuracy compared with aBMD alone. Further inclusion of age and prevalent vertebral deformity in the model improved vertebral fracture prediction, and TBS remained significant in the model. Thus, lower TBS was associated with higher risk of vertebral fracture over 10 years independently of aBMD and clinical risk factors including prevalent vertebral deformity. TBS could effectively improve fracture risk assessment in clinical settings. © 2014 American Society for Bone and Mineral Research.  相似文献   
999.

Purpose

Long-term dialysis often causes physiological and metabolic problems that may affect the outcomes of surgery. The aim of this study was to elucidate whether emergency surgery for acute abdomen yields similar outcomes in dialysis patients versus non-dialysis patients.

Methods

The subjects were 126 patients who underwent emergency surgery for acute abdomen between January, 2007 and November, 2011 in our hospital. They were divided into a dialysis group (HD group; n = 9) and a non-dialysis group (non-HD group; n = 117) and their postoperative morbidity and mortality were compared.

Results

Postoperative morbidity and mortality were significantly worse in the HD group. All 9 of these patients succumbed to postoperative complications versus only 5 of the 117 patients in the non-HD group.

Conclusion

The outcomes of emergency surgery for acute abdomen were significantly worse for dialysis patients than for non-dialysis patients. Prompt diagnosis, initiation of the most suitable surgical procedure, and meticulous postoperative cares are imperative to improving the surgical outcomes of dialysis patients.  相似文献   
1000.

Purpose

We assessed the incidence of coronary artery disease (CAD) during hospitalization after emergency surgery for a type A acute aortic dissection.

Methods

A total of 123 patients underwent multi-slice computed tomography (MSCT) scans during an early stage after surgery. The patients were divided into two groups: group I consisted of 14 patients (11.4 %) who had coronary artery stenosis of more than 75 % on MSCT, and group II consisted of 109 patients (88.6 %) who had no coronary lesions.

Results

The prevalence of diabetes, dyslipidemia and a smoking history was significantly higher in group I. Although the serum low-density lipoprotein cholesterol levels were similar, the high-density lipoprotein cholesterol (HDL) level was significantly lower in group I (36.4 ± 7.9 mg/dl) than in group II (49.6 ± 13.5 mg/dl, P = 0.0005). The maximum carotid intima-media thickness (IMT) was significantly thicker in group I (1.17 ± 0.37 mm) compared to group II (0.96 ± 0.33 mm, P = 0.0297). The logistic regression analysis detected that a carotid IMT over 1.1 mm (odds ratio 4.35, P = 0.0371) and HDL less than 40 mg/dl (odds ratio 3.90, P = 0.0482) were predictors for CAD.

Conclusions

CAD screening should be recommended for patients with aortic dissection who have several atherosclerosis risk factors, even after emergency surgery.  相似文献   
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