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Age-associated changes in decorin in rat mandibular condylar cartilage   总被引:3,自引:0,他引:3  
The small proteoglycan decorin strongly binds the fibrils of collagen types I and II; this interaction is thought to play a part in the maintenance of tissue integrity and biomechanical properties. In limb articular cartilage, there is evidence that decorin synthesis increases with age and that it is elevated in response to increased loading or in osteoarthritic cartilage. The aim here was to characterize the presence and relative amount of decorin in the condylar cartilage of the temporomandibular joint (TMJ) with maturation by Western blotting, and to assess its tissue localization by immunohistochemistry. Comparative data were obtained from tibial articular cartilage, which has been extensively studied. Cartilage from the mandibular condyle and tibial plateau was harvested from 24-day-old (growing) and 161-day-old (young adult) female Sprague-Dawley rats. In growing animals, decorin appeared slightly more abundant in the mandibular condylar cartilage than in articular cartilage, whereas in young adult animals the decorin content in the TMJ cartilage was noticeably less than in limb articular cartilage. Although there was an increase in decorin abundance with age at the TMJ, the increase in decorin with age in limb articular cartilage was considerably more pronounced. These data indicate that, although decorin is present in mandibular condylar cartilage, its abundance in adults is less than in limb articular cartilage; thus, maturation-associated changes may be dissimilar in magnitude from those documented for limb articular cartilage.  相似文献   
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Juvenile salmon transitioning from freshwater to marine environments experience high variation in growth and survival, yet the specific causes of this variation are poorly understood. Size at and timing of ocean entry may contribute to this variation because they influence both the availability of prey and vulnerability to predators. To explore this issue, we used stock assignments based on genetic stock identification and internal tags to document the stock-specific size and timing of juvenile hatchery and presumed wild Columbia River Chinook Salmon Oncorhynchus tshawytscha and steelhead O. mykiss at ocean entry during 2007–2011. We found that juvenile salmon and steelhead had consistent stock-specific capture dates, with lower-river stocks typically having earlier timing than those originating farther upstream. Mean size also varied among stocks and was related to hatchery practices. Hatchery yearling Chinook Salmon and steelhead were consistently larger than wild fish from the same stocks, although timing in the estuary was similar. In contrast, hatchery subyearling Chinook Salmon were of similar size to wild fish but entered the ocean up to a month earlier. We evaluated the potential importance of these traits on early marine growth by estimating stock-specific growth rates for Chinook Salmon caught in estuarine and ocean habitats. Growth rates were related to relative ocean entry timing, with lower growth rates for stocks that had only recently arrived in marine waters. Our results demonstrate that stocks within a single basin can differ in their size and timing of ocean entry, life history traits that contribute to early marine growth and potentially to the survival of juvenile salmon. Our results also highlight the necessity of considering stock-specific variation in life history traits to understand salmon ecology and survival across the entire life cycle.

Received January 16, 2015; accepted April 28, 2015  相似文献   

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BackgroundRadiation therapy has proven efficacy for cancer treatment but is not without short- and long-term side effects, including radiation-induced lymphedema. There has been limited evidence on the secondary effects of prior radiation therapy on shoulder surgery. The purpose of this study is to evaluate the short-term outcomes of shoulder arthroplasty and rotator cuff repair (RCR) in patients who have undergone ipsilateral radiation therapy and/or have preoperative upper extremity lymphedema.MethodsDuke Enterprise Data Unified Content Explorer was used to query for patients who underwent RCR at our institution. Patients with radiation therapy for breast or lung cancer prior to ipsilateral RCR or shoulder arthroplasty were included. Patients with less than 2 years of follow-up were excluded. Data variables included primary tumor type, dates of cancer diagnoses, radiation treatment, axillary lymph node dissection (aLND), presence of lymphedema, index shoulder operations, most recent follow-up, and surgical and medical complications within the 90-day postoperative period. Additional oncologic variables included total Gray (Gy) delivered.ResultsTwenty-one patients underwent radiation therapy and subsequent shoulder arthroplasty or RCR (13 RCR, 3 total shoulder arthroplasty, 5 reverse shoulder arthroplasty). There were 20 females and 1 male with an average age of 65.6 years (47-82) and average clinical follow-up of 4.4 years (2.0-7.4). Oncologic diagnoses included lung (4.8%) and breast (95.2%) cancer. Average radiation dose delivered was 53.3 Gy (38.5-64) in the cohort. The average time from last external beam radiation therapy to shoulder surgery was 4.3 years (0.3-18.0). One of 13 (7.7%) 90-day postoperative complications was reported in the RCR cohort: a superficial vein thrombosis. One of 8 (12.5%) 90-day complications was reported in the arthroplasty cohort: a clinically suspected but radiographically absent acromial stress fracture in a reverse shoulder arthroplasty that did not require operative intervention. Overall, there were no revisions, reoperations, or shoulder-related unplanned inpatient 90-day readmissions. Among 10 patients with prior aLND, 3 (30%) (2 RCR, 1 arthroplasty) experienced new or worsening upper extremity lymphedema within the immediate postoperative period.ConclusionA minority of patients having undergone prior radiation therapy and aLND who subsequently underwent ipsilateral shoulder surgery experienced worsening subjective upper extremity lymphedema. Although 10% of these radiation therapy patients experienced minor complications within 90 days of their shoulder surgery, none were severe enough to merit inpatient admission or revision surgery.  相似文献   
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BackgroundThousands of patients annually receive treatment for advanced non‐small cell lung cancer (NSCLC), but little is known about their views on the decision to receive that treatment, or regret. This trial prospectively evaluated the incidence of regret and whether baseline characteristics, patient decision‐making parameters, or clinical progress early in the treatment course predicts regret.Materials and MethodsPatients receiving systemic treatment for advanced NSCLC completed every 3‐week patient reported outcome (PRO) assessment using the electronic Lung Cancer Symptom Scale (eLCSS‐QL), including the 3‐Item Global Index (3‐IGI; assessing overall distress, activities, and quality of life [QL]). A prespecified secondary aim was to determine the frequency of regret evaluated at 3 months after starting treatment. Patients were randomized to usual care or enhanced care (which included use of the DecisionKEYS decision aid).ResultsOf 164 patients entered, 160 received treatment and 142 were evaluable for regret. In total, 11.5% of patients and 9% of their supporters expressed regret. Baseline characteristics did not predict regret; regret was rarely expressed by those who had a less than 20% decline or improvement in the 3‐IGI PRO score after two treatment cycles. In contrast, when asked if they would make the same decision again, only 1% not having a 20% 3‐IGI decline expressed regret, versus 14% with a 3‐IGI decline (p = .01).ConclusionThe majority of patients having regret were identified early using the PRO 3‐IGI of the eLCSS‐QL measure. Identifying patients at risk for regret allows for interventions, including frank discussions of progress and goals early in the treatment course, which could address regret in patients and their supporters.Implications for PracticeThis report documents prospectively, for the first time, the incidence of treatment‐related regret in patients with advanced lung cancer and outlines that risk of regret is associated with patient‐determined worsening health status early in the course of treatment. Identifying patients at risk for regret early in treatment (before the third cycle of treatment) appears to be crucial. Counseling at that time should include a discussion of consideration of treatment change and the reason for this change.  相似文献   
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This study presents a conceptual model of the supply and demand for mental health professionals. It uses national data to profile differences in the supply of mental health professionals in different types of rural and urban areas. It contrasts the availability of general health and mental health professionals. It examines shortage areas identified in 2000 and their related community characteristics. Because of the absence of data on a national level to describe many types of mental health professionals state licensure data for one state were used to show the volume and distribution of these practitioners. To improve rural mental health service delivery it will be necessary to implement system changes to promote the increased availability, competency, and support of rural health professionals.  相似文献   
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