Artificial organs
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Functional electrical stimulation (FES) of long-term denervated, degenerated human skeletal muscle has proven to be a suitable method for improving a number of physiological parameters. The underlying mechanisms of activation of a denervated muscle fiber can be described with suitably modified and extended Hodgin-Huxley type models, coupled with three-dimensional (3D) finite element models of the surrounding electrical field. Regions of activation within a muscle can be determined using a 3D computer model. ⋯ Activation was detected in all patients. In well-trained patients, activation in the quadriceps was found to be considerably higher than in its antagonists. These experimental results will help further improve existing models of FES of denervated degenerated human skeletal muscle.
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Randomized Controlled Trial
Intra-aortic balloon pump-induced pulsatile flow reduces coagulative and fibrinolytic response to cardiopulmonary bypass.
The aim of this study is to evaluate if a simple intra-aortic balloon pump (IABP)-induced pulsatile perfusion reduces activation of coagulative system during cardiopulmonary bypass (CPB). Ninety-six patients undergoing preoperative IABP were randomized to nonpulsatile CPB with IABP discontinued during cardioplegic arrest (Group A) or IABP-induced pulsatile CPB (Group B). White blood cells (WBC), hematocrit (Ht), platelets (PLTs), International Normalized Ratio (INR), fibrinogen, activated partial thromboplastin time (aPTT), antithrombin III (AT-III) activity, and D-dimer were measured at the end of surgery (ES) and postoperatively. ⋯ Group B showed lower chest drainage (1st day P = 0.038; 2nd day P = 0.044), transfusions (P = 0.031), WBC (P < 0.05 at all time points), and INR (P < 0.05 at all time points), together with a higher Ht (P < 0.05 at ES, 12 h), platelets (P < 0.04 at all time points), fibrinogen (P < 0.05 at ES, 12 h, 24 h), and aPTT (P < 0.05 at all time points). AT-III activity lowered in Group A (P = 0.001 at ES, 12 h, 24 h), together with higher D-dimer levels (P < 0.05 at all time points). IABP-induced pulsatile perfusion ameliorates coagulative system activation following CPB.
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Numerous studies suggest a strong association between nutrition and clinical outcome in chronic hemodialysis (HD) patients. While determination of malnutrition is often based on objective measurements, such as biochemical parameters and anthropometric data, there is no single measurement that can reliably predict the risk for malnutrition or poor outcome. The aim of the present investigation was to determine the prevalence and severity of malnutrition among HD patients in a large university-affiliated HD center in Serbia, and to examine the relationship between various nutritional and nonnutritional factors, and the clinical outcome in the period of 20 months follow-up. ⋯ After adjusting for age and sex, only comorbid medical problems expressed as ICED (OR 5.28; P < 0.01), DMS (OR 1.21; P < 0.01), and C-reactive protein (CRP) (OR 1.04; P < 0.05) were significant predictors of mortality. In conclusion, malnutrition in the Serbian cohort of patients on HD was very common. Nutritional status at enrollment (expressed as DMS), presence of comorbidity (ICED index), and CRP level were strong predictors of mortality during the 20 months of follow-up.
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Randomized Controlled Trial Comparative Study
Comparative effectiveness of methylprednisolone and zero-balance ultrafiltration on inflammatory response after pediatric cardiopulmonary bypass.
Studies have demonstrated that systemic inflammatory response syndrome (SIRS) remains one of the major causes of cardiopulmonary bypass (CPB)-associated organ injury during pediatric cardiac surgery. The purpose of this investigation was to compare the effectiveness of methylprednisolone (MP) and zero-balance ultrafiltration (ZBUF) on SIRS during pediatric CPB. Thirty infants undergoing open-heart surgeries were randomized to receive either MP in the priming solution (group M, n = 15) or ZBUF during CPB (group Z, n = 15). ⋯ There was no difference between two groups on the plasma concentrations of IL-10. The duration of postoperative mechanical ventilation was (9.6 +/- 0.8 h) in the M group and (7.8 +/- 0.4 h) in the Z group (P < 0.05). This study showed that application of ZBUF is more effective to decrease the level of inflammatory mediators including TNF-alpha, IL-6, and IL-8 than administration of MP after pediatric CPB.
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We have developed internal battery systems for driving an undulation pump ventricular assist device using two kinds of lithium ion rechargeable batteries. The lithium ion rechargeable batteries have high energy density, long life, and no memory effect; however, rise in temperature of the lithium ion rechargeable battery is a critical issue. Evaluation of temperature rise by means of numerical estimation is required to develop an internal battery system. ⋯ K) in the Li-po battery depending on state of charge (SOC). Temperature of each lithium ion rechargeable battery under a discharge current of 1 A was estimated by finite element method heat transfer analysis at an ambient temperature of 37 degrees C configuring with measured R(cell) and measured DeltaS in each SOC. Results of estimation of time-course change in the surface temperature of each battery coincided with results of measurement results, and the success of the estimation will greatly contribute to the development of an internal battery system using lithium ion rechargeable batteries.