38 research outputs found

    Tezosentan normalizes hepatomesenteric perfusion in a porcine model of cardiac tamponade

    No full text
    BACKGROUND: To investigate endothelin-1 (ET-1)-dependent hepatic and mesenteric vasoconstriction, and oxygen and lactate fluxes in an acute, fixed low cardiac output (CO) state. METHODS: Sixteen anesthetized, mechanically ventilated pigs were studied. Cardiac tamponade was established to reduce portal venous blood flow (Q(PV)) to 2/3 of the baseline value. CO, hepatic artery blood flow (Q(HA)), Q(PV), hepatic laser-Doppler flow (LDF), hepatic venous and portal pressure, and hepatic and mesenteric oxygen and lactate fluxes were measured. Hepatic arterial (R(HA)), portal (R(HP)) and mesenteric (R(mes)) vascular resistances were calculated. The combined ET(A)-ET(B) receptor antagonist tezosentan (RO 61-0612) or normal saline vehicle was infused in the low CO state. Measurements were made at baseline, after 30, 60, 90 min of tamponade, and 30, 60, 90 min following the infusion of tesozentan at 1 mg/kg/h. RESULTS: Tamponade decreased CO, Q(PV), Q(HA), LDF, hepatic and mesenteric oxygen delivery, while hepatic and mesenteric oxygen extraction and lactate release increased. R(HA), R(HP) and R(mes) all increased. Ninety minutes after tesozentan, Q(PV), LDF and hepatic and mesenteric oxygen delivery and extraction increased approaching baseline values, but no effect was seen on CO or Q(HA). Hepatic and mesenteric handling of lactate converted to extraction. R(HA), R(HP) and R(mes) returned to baseline values. No changes were observed in these variables among control animals not receiving tesozentan. CONCLUSION: In a porcine model of acute splanchnic hypoperfusion, unselective ET-1 blockade restored hepatomesenteric perfusion and reversed lactate metabolism. These observations might be relevant when considering liver protection in low CO states

    Self-congruity theory: to what extent does it hold in tourism?

    Get PDF
    This paper investigates (1) if, and to what extent, self-congruity theory is applicable in tourism, (2) to what extent travel and person characteristics explain the degree of self-congruity, and (3) how the operationalization of self-congruity affects the conclusions about whether self-congruity holds in tourism. Results derived from a large-scale study of Swiss travelers indicate that conclusions depend heavily on how self-congruity is measured. Using a relatively strict measure, more than half the trips under study can be classified as self-congruent. However, travel and sociodemographic characteristics are very limited in their ability to explain when self-congruity occurs

    Improvement rates, adverse events and predictors of clinical outcome following surgery for degenerative cervical myelopathy

    No full text
    PURPOSE: To investigate improvement rates, adverse events and predictors of clinical outcome after laminectomy alone (LAM) or laminectomy with instrumented fusion (LAM + F) for degenerative cervical myelopathy (DCM). METHODS: This is a post hoc analysis of a previously published DCM cohort. Improvement rates for European myelopathy score (EMS) and Neck Disability Index (NDI) at 2- and 5-year follow-ups and adverse events are presented descriptively for available cases. Predictor endpoints were EMS and NDI scores at follow-ups, surgeon- and patient-reported complications, and reoperation-free interval. For predictors, univariate and multivariable models were fitted to imputed data. RESULTS: Mean age of patients (LAM n = 412; LAM + F n = 305) was 68 years, and 37.4% were women. LAM + F patients had more severe spondylolisthesis and less severe kyphosis at baseline, more surgeon-reported complications, more patient-reported complications, and more reoperations (p ≤ 0.05). After imputation, the overall EMS improvement rate was 43.8% at 2 years and 36.3% at 5 years. At follow-ups, worse EMS scores were independent predictors of worse EMS outcomes and older age and worse NDI scores were independent predictors of worse NDI outcomes. LAM + F was associated with more surgeon-reported complications (ratio 1.81; 95% CI 1.17-2.80; p = 0.008). More operated levels were associated with more patient-reported complications (ratio 1.12; 95% CI 1.02-1.22; p = 0.012) and a shorter reoperation-free interval (hazard ratio 1.30; 95% CI 1.08-1.58; p = 0.046). CONCLUSIONS: These findings suggest that surgical intervention at an earlier myelopathy stage might be beneficial and that less invasive procedures are preferable in this patient population

    MRI-based measurements of spondylolisthesis and kyphosis in degenerative cervical myelopathy

    No full text
    Background: To provide normative data and to determine accuracy and reliability of preoperative measurements of spondylolisthesis and kyphosis on supine static magnetic resonance imaging (MRI) of patients with degenerative cervical myelopathy. Methods: T2-weighted midsagittal images of the cervical spine were in 100 cases reviewed twice by one junior observer, with an interval of 3 months, and once by a senior observer. The spondylolisthesis slip (SSlip, mm) and the modified K-line interval (mK-line INT, mm) were assessed for accuracy with the standard error of measurement (SEm) and the minimum detectable change (MDC). Intraobserver and interobserver reliability levels were determined using the intraclass correlation coefficient (ICC). Results: The SEm was 0.5 mm (95% CI 0.4-0.6) for spondylolisthesis and 0.6 mm (95% CI 0.5-0.7) for kyphosis. The MDC, i.e., the smallest difference between two examinations that can be detected with statistical certainty, was 1.5 mm (95% CI 1.2-1.8) for spondylolisthesis and 1.6 mm (95% CI 1.3-1.8) for kyphosis. The highest reliability levels were seen between the second observation of the junior examiner and the senior observer (ICC = 0.80 [95% CI 0.70-0.87] and ICC = 0.96 [95% CI 0.94-0.98] for SSlip and mK-line INT, respectively). Conclusions: This study provides normative values of alignment measurements of spondylolisthesis and kyphosis in DCM patients. It further shows the importance of taking measurement errors into account when defining cut-off values for cervical deformity parameters and their potential clinical application in surgical decision-making

    A single load of fructose attenuates the risk of exercise-induced hypoglycemia in adults with type 1 diabetes on ultra-long-acting basal insulin: A randomized, open-label, crossover proof-of-principle study

    No full text
    OBJECTIVE While the adjustment of insulin is an established strategy to reduce the risk of exercise-associated hypoglycemia for individuals with type 1 diabetes, it is not easily feasible for those treated with ultra-long-acting basal insulin. The current study determined whether pre-exercise intake of fructose attenuates the risk of exercise-induced hypoglycemia in individuals with type 1 diabetes using insulin degludec. RESEARCH DESIGN AND METHODS Fourteen male adults with type 1 diabetes completed two 60-min aerobic cycling sessions with or without prior intake (30 min) of 20 g of fructose, in a randomized two-period crossover design. Exercise was performed in the morning in a fasted state without prior insulin reduction and after 48 h of standardized diet. The primary outcome was time to hypoglycemia (plasma glucose ≤3.9 mmol/L) during exercise. RESULTS Intake of fructose resulted in one hypoglycemic event at 60 min compared with six hypoglycemic events at 27.5 ± 9.4 min of exercise in the control condition, translating into a risk reduction of 87.8% (hazard ratio 0.12 [95% CI 0.02, 0.66]; P = 0.015). Mean plasma glucose during exercise was 7.3 ± 1.4 mmol/L with fructose and 5.5 ± 1.1 mmol/L in the control group (P < 0.001). Lactate levels were higher at rest in the 30 min following fructose intake (P < 0.001) but were not significantly different from the control group during exercise (P = 0.32). Substrate oxidation during exercise did not significantly differ between the conditions (P = 0.73 for carbohydrate and P = 0.48 for fat oxidation). Fructose was well tolerated. CONCLUSIONS Pre-exercise intake of fructose is an easily feasible, effective, and well-tolerated strategy to alleviate the risk of exercise-induced hypoglycemia while avoiding hyperglycemia in individuals with type 1 diabetes on ultra-long-acting insulin. © 2020 by the American Diabetes Association

    Volumetric food quantification using computer vision on a depth-sensing smartphone: Preclinical study

    No full text
    Background: Quantification of dietary intake is key to the prevention and management of numerous metabolic disorders. Conventional approaches are challenging, laborious, and lack accuracy. The recent advent of depth-sensing smartphones in conjunction with computer vision could facilitate reliable quantification of food intake. Objective: The objective of this study was to evaluate the accuracy of a novel smartphone app combining depth-sensing hardware with computer vision to quantify meal macronutrient content using volumetry. Methods: The app ran on a smartphone with a built-in depth sensor applying structured light (iPhone X). The app estimated weight, macronutrient (carbohydrate, protein, fat), and energy content of 48 randomly chosen meals (breakfasts, cooked meals, snacks) encompassing 128 food items. The reference weight was generated by weighing individual food items using a precision scale. The study endpoints were (1) error of estimated meal weight, (2) error of estimated meal macronutrient content and energy content, (3) segmentation performance, and (4) processing time. Results: In both absolute and relative terms, the mean (SD) absolute errors of the app's estimates were 35.1 g (42.8 g; relative absolute error: 14.0% [12.2%]) for weight; 5.5 g (5.1 g; relative absolute error: 14.8% [10.9%]) for carbohydrate content; 1.3 g (1.7 g; relative absolute error: 12.3% [12.8%]) for fat content; 2.4 g (5.6 g; relative absolute error: 13.0% [13.8%]) for protein content; and 41.2 kcal (42.5 kcal; relative absolute error: 12.7% [10.8%]) for energy content. Although estimation accuracy was not affected by the viewing angle, the type of meal mattered, with slightly worse performance for cooked meals than for breakfasts and snacks. Segmentation adjustment was required for 7 of the 128 items. Mean (SD) processing time across all meals was 22.9 seconds (8.6 seconds). Conclusions: This study evaluated the accuracy of a novel smartphone app with an integrated depth-sensing camera and found highly accurate volume estimation across a broad range of food items. In addition, the system demonstrated high segmentation performance and low processing time, highlighting its usability. © 2020 Journal of Medical Internet Research. All rights reserved
    corecore