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51.
Haack M  Sanchez E  Mullington JM 《Sleep》2007,30(9):1145-1152
CONTEXT: Sleep disturbances, pain, and inflammation co-occur in various medical conditions, but their interrelationships are poorly understood. OBJECTIVE: We investigated the effects of reduced sleep duration (by approximately 50%) to 4 h/night across 10 days, on peripherally circulating inflammatory mediators. In addition, we tested the prediction that degree of inflammation is quantitatively related to the extent to which pain is increased in response to prolonged sleep restriction. DESIGN: Randomized, 16 day controlled in-laboratory study conducted in GCRC. METHODS: Eighteen volunteers were randomly assigned to either 12 days of sleeping 8 h/night or 4 h/night. Participants rated mood and pain symptoms throughout experimental days. Urine was collected and blood was drawn frequently on the baseline day and after the 10th experimental day for 25 hours. OUTCOME MEASURES: Levels of plasma interleukin (IL)-6, serum C-reactive protein (CRP), plasma soluble tumor necrosis factor receptor p55 (sTNF-R p55), urinary levels of prostaglandin (PG) metabolites D2 and E2, subjective assessment of pain and tiredness-fatigue. RESULTS: IL-6 levels were elevated in the 4-h sleep condition over the 8-h sleep condition (P <0.05). CRP levels showed the same trend as IL-6, but did not differ significantly between groups (P = 0.11). Levels of sTNF-R p55 were unchanged in both groups. PG E2 and 11beta-F2alpha metabolite increased in 4-h sleepers, but did not differ significantly from the 8-h sleepers. Elevated IL-6 levels were strongly associated with increased pain ratings in response to sleep restriction (r = 0.67, P <0.01), and this association could not be explained by elevations in tiredness-fatigue. CONCLUSION: Insufficient sleep quantity may facilitate and/or exacerbate pain through elevations of IL-6. In disorders where sleep disturbances are common, insufficient sleep quantity itself may establish and maintain its co-occurrence with pain and increased inflammation.  相似文献   
52.

Aim

Nutritional screening may not always lead to intervention. The present study aimed to determine: (i) the rate of nutritional screening in hospitalised older adults; (ii) whether nutritional screening led to dietitian consultation and (iii) factors associated with malnutrition.

Methods

In this prospective study of patients aged ≥70 years admitted to a Geriatric Evaluation and Management Unit (GEMU), malnutrition was screened for using the Mini Nutritional Assessment Short Form (MNA‐SF) and identified using the Mini Nutritional Assessment (MNA).

Results

Of the 172 patients participating in the study, 53 (30.8%) patients were malnourished, and 84 (48.8%) were at risk of malnutrition. Mean (SD) age was 85.2 (6.4 years), with 131 patients (76.2%) female. Nutritional screening was performed for all patients; however, it was incomplete in 59 (34.3%) because of omission of the anthropometric measurement. Overall, 62 (36.0%) of the total number of patients were seen by the dietitian, which included 26 (49%) of malnourished patients, 27 (32%) of at‐risk patients and 9 (26%) of the well‐nourished patients. No patients lost >1% of body weight during GEMU stay. Malnourished patients were more likely to be frail, have poor appetite, depression, and have lower levels of: albumin, cognition, physical function, grip strength and quality of life.

Conclusions

The full benefits of nutritional screening by MNA‐SF may not be realised if it does not result in malnourished patients receiving a dietitian consultation. However, it is possible that enrichment of the foodservice with high protein/high‐energy options minimised patient weight loss in the GEMU.  相似文献   
53.
Photocrosslinkable magnetic hydrogels are attracting great interest for tissue engineering strategies due to their versatility and multifunctionality, including their remote controllability ex vivo, thus enabling engineering complex tissue interfaces. This study reports the development of a photocrosslinkable magnetic responsive hydrogel made of methacrylated chondroitin sulfate (MA-CS) enriched with platelet lysate (PL) with tunable features, envisioning their application in tendon-to-bone interface. MA-CS coated iron-based magnetic nanoparticles were incorporated to provide magnetic responsiveness to the hydrogel. Osteogenically differentiated adipose-derived stem cells and/or tendon-derived cells were encapsulated within the hydrogel, proliferating and expressing bone- and tendon-related markers. External magnetic field (EMF) application modulated the swelling, degradation and release of PL-derived growth factors, and impacted both cell morphology and the expression and synthesis of tendon- and bone-like matrix with a more evident effect in co-cultures. Overall, the developed magnetic responsive hydrogel represents a potential cell carrier system for interfacial tissue engineering with EMF-controlled properties.  相似文献   
54.
OBJECTIVE: To compare the short-term outcomes of active individual therapy (AIT) with those of a functional restoration program (FRP). DESIGN: Prospective randomized controlled study. SETTING: Two rehabilitation centers and private ambulatory physiotherapy facilities. PARTICIPANTS: One hundred thirty-two adults with chronic low back pain. Fifty-one percent of patients on sick leave or out of work (mean duration, 180d in the 2y before treatment). INTERVENTIONS: For 5 weeks, FRP (at 25h/wk) or AIT (at 3h/wk). MAIN OUTCOME MEASURES: Trunk flexibility, back flexor, and extensor endurance (Ito and Sorensen tests), general endurance, pain intensity, Dallas Pain Questionnaire (DPQ) scores, daily activities, anxiety depression, social interest, and work and leisure activities, and self-reported improvement (work ability, resumption of sport and leisure activities). RESULTS: All outcome measures improved after treatment except endurance in AIT. There was no between-group difference for pain intensity or DPQ daily activities or work and leisure activities scores. Better results were observed in FRP for all other outcome measures. There was a significant effect of treatment and the initial value for the gain of the Sorensen score with a treatment or initial value interaction; a significant effect of treatment and initial value on the gains of Ito, endurance, and DPQ social interest and anxiety depression scores, with no treatment or initial value interaction; and a significant effect of initial value but not treatment for the gains of DPQ daily activities and work and leisure activities scores. CONCLUSIONS: Low-cost ambulatory AIT is effective. The main advantage of FRP is improved endurance. We speculate that this may be linked to better self-reported work ability and more frequent resumption of sports and leisure activities.  相似文献   
55.
Previous studies in the wetland macrophyte Bidens laevis L have demonstrated that the insecticide endosulfan induces a high frequency of somatic chromosome aberrations in anaphase–telophase (CAAT) but no DNA changes as determined by the single cell gel electrophoresis (Comet) assay. Thus, cytogenetic biomarkers appear to be more sensitive to the toxic effects of the insecticide than the DNA molecule in the studied species. For this reason, the goals of this study were to use cytogenetic biomarkers—CAAT and abnormal metaphase—and defense biomarkers such as the activity of the antioxidant enzymes—guaiacol peroxidases (POD), glutathione reductase, and microsomal and cytosolic (m‐ and c‐) glutathione‐S‐transferase (GST)—to evaluate in B. laevis effects caused by a commercial formulation of endosulfan. The frequency of CAAT was increased at 5, 10, 50, and 100 μg/L endosulfan with respect to the negative controls by 3.1, 2.5, 2.5, and 3.2‐fold, respectively while the frequency of abnormal metaphases was also increased at the same concentrations by 3.5, 2.8, 3.2, and 11.3‐fold, respectively. In addition to these aneugenic effects, other abnormalities such as C‐mitosis and chromosome clumping were observed at 10 μg/L endosulfan. On the other hand, POD induction at 0.02, 0.5, 5, and 10 μg/L and m‐GST inhibition at 0.5, 10, and 50 μg/L in plants exposed during 24 h to endosulfan were observed but all of these responses were highly variable. In conclusion, only cytogenetic biomarkers like CAAT in B. laevis can serve potentially as early warning systems to detect environmentally relevant concentrations of endosulfan in aquatic ecosystems. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1063–1071, 2014.  相似文献   
56.
57.

Background

Ovarian cancer arising in women with BRCA mutations is known to have a more favorable outcome and to be more responsive to platinum-based regimens than in those without a hereditary background. We analyze our previously published intraperitoneal (IP) studies in relation to BRCA mutation status and update their outcomes.

Methods

Among 62 patients with ovarian cancer enrolled in IP platinum doublet studies in clinical trials (with etoposide (n = 18), with floxuridine (n = 30), and with topotecan (n = 14)), a deleterious BRCA mutation was eventually identified in 10 patients. The outcomes in these BRCA mutation carriers are described and compared with survival of others in respective trials.

Results

Ten patients that were confirmed to have BRCA mutations—all with high-grade and stages IIC to IV disease—survived a median of 10 years (range: 4–18+) after receiving IP cisplatin-based regimens. Two continue with no evidence of disease since their IP treatment, while four others remain alive with recurrences after 8, 9, 10, and 11 years, respectively.

Conclusions

This experience suggests that IP cisplatin leads to favorable long term outcomes in advanced ovarian cancer in women with defective homologous recombination (i.e., with deleterious BRCA mutations). Whether such cisplatin dose-intensification from IP relative to (intravenous) IV drug administration leads to superior results in these mutation carriers requires further study.  相似文献   
58.
BACKGROUND/AIMS: The aim of this study was to evaluate long term safety and antiviral activity of different doses of emtricitabine given once daily to patients chronically infected with hepatitis B. METHODS: Eligible patients were randomized in a double-blind, parallel study to evaluate 25, 100 or 200 mg once daily doses of emtricitabine for 48 weeks. Patients were then followed for an additional 48 weeks on open-label 200 mg emtricitabine. Serum HBV DNA, ALT, and hepatitis B serology were measured at regular intervals over the 2 years. Resistance surveillance was performed after 1 and 2 years on viremic samples, i.e. > 4700 copies/mL. RESULTS: Emtricitabine was well tolerated and produced a dose proportional antiviral response. After 2 years, 53% of the patients had serum HBV DNA < or = 4700 copies/mL, 33% seroconverted to anti-HBe and 85% had normal ALT. Eighteen percent of the patients who had received 200 mg emtricitabine for 2 years developed resistance mutations. CONCLUSIONS: Emtricitabine was well tolerated and demonstrated a potent antiviral response for up to 2 years in patients with chronic hepatitis B infection. Based on these data, 200 mg emtricitabine once daily was chosen as the optimal dose for future hepatitis B studies.  相似文献   
59.
60.
Petrographic analysis of Formative Mexican ceramics by J. B. Stoltman et al. (see the companion piece in this issue of PNAS) refutes a recent model of Olmec "one-way" trade. In this paper, we address the model's more fundamental problems of sampling bias, anthropological implausibility, and logical non sequiturs. No bridging argument exists to link motifs on pottery to the social, political, and religious institutions of the Olmec. In addition, the model of unreciprocated exchange is implausible, given everything that the anthropological and ethnohistoric records tell us about non-Western societies of that general sociopolitical level.  相似文献   
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