Can postoperative mean transprosthetic pressure gradient predict survival after aortic valve replacement?

BACKGROUND: In this study, we sought to determine the effect of the mean transprosthetic pressure gradient (TPG), measured at 6 weeks after aortic valve replacement (AVR) or AVR with coronary artery bypass grafting (CABG) on late all-cause mortality. METHODS: Between January 1998 and March 2012, 2,276 patients (mean age 68 ± 11 years) underwent TPG analysis at 6 weeks after AVR (n = 1,318) or AVR with CABG (n = 958) at a single institution. Mean TPG was 11.6 ± 7.8 mmHg and median TPG 11 mmHg. Based on the TPG, the patients were split into three groups: patients with a low TPG (<10 mmHg), patients with a medium TPG (10–19 mmHg) and patients with a high TPG (≥20 mmHg). Cox proportional-hazard regression analysis was used to determine univariate predictors and multivariate independent predictors of late mortality. RESULTS: Overall survival for the entire group at 1, 3, 5, and 10 years was 97, 93, 87 and 67 %, respectively. There was no significant difference in long-term survival between patients with a low, medium or high TPG (p = 0.258). Independent predictors of late mortality included age, diabetes, peripheral vascular disease, renal dysfunction, chronic obstructive pulmonary disease, a history of a cerebrovascular accident and cardiopulmonary bypass time. Prosthesis–patient mismatch (PPM), severe PPM and TPG measured at 6 weeks postoperatively were not significantly associated with late mortality. CONCLUSIONS: TPG measured at 6 weeks after AVR or AVR with CABG is not an independent predictor of all-cause late mortality and there is no significant difference in long-term survival between patients with a low, medium or high TPG

The influence of oxygen delivery during cardiopulmonary bypass on the incidence of delirium in CABG patients; a retrospective study

Introduction: Postoperative delirium is the most common neurological complication of cardiac surgery. Hypoxia has been shown to increase the risk of postoperative delirium. The possibility to continuously monitor oxygen delivery (DO2) during cardiopulmonary bypass (CPB) offers an adequate approximation of the oxygen status in a patient. This study investigates the role of oxygen delivery during cardiopulmonary bypass in the incidence of postoperative delirium. Methods: Three hundred and fifty-seven adult patients who underwent normothermic coronary artery bypass grafting (CABG) surgery were included in this retrospective study. The nadir indexed DO2 (DO2i) value on bypass, the total time under the critical DO2i level and the area under the curve (AUC) for critical DO2i were determined. Delirium was identified by the postoperative administration of haloperidol. Results: The mean nadir DO2i significantly differed, comparing the group of patients with postoperative delirium to the group without. Multivariate analysis only identified age, pre-existing cognitive impairment, preoperative kidney dysfunction and cross-clamp time as independent risk factors for delirium. The results also indicated that patients of older age were more sensitive to a declined DO2i. Conclusion: A low DO2i during cardiopulmonary bypass is significantly associated with the incidence of postoperative delirium in CABG patients. However, the role of DO2 as an independent predictor of delirium could not be proven

The impact of surgical aortic valve replacement on quality of life-a multicenter study:a multicenter study

OBJECTIVES: To explore the effect of surgical aortic valve replacement on quality of life and the variance with age, particularly in patients at risk of deterioration. METHODS: In an observational, multicenter, cohort study of routinely collected health data, patients undergoing and electively operated between January 2011 and January 2015 with pre- and postoperative quality of life data were included. Patients were classified into 3 age groups: 5-point difference as a minimal clinically important difference. Multivariable linear regression analysis, with adjustment for confounders, was used to evaluate the association between age and quality of life. RESULTS: In 899 patients, mean physical health increased from 55 to 66 and mental health from 60 to 66. A minimal clinically important decreased physical health was observed in 12% of patients aged <65 years, 16% of patients aged 65-79 years, and 22% of patients aged ≥80 years (P = .023). A decreased mental health was observed in 15% of patients aged <65 years, 22% of patients aged 65-79 years, and 24% aged ≥80 years (P = .030). Older age and a greater physical and mental score at baseline were associated with a decreased physical and mental quality of life (P < .001). CONCLUSIONS: Patients surviving surgical aortic valve replacement on average improve in physical and mental quality of life; nonetheless, with increasing age patients are at higher risk of experiencing a deterioration

Laser-cooling simulation based on the semiclassical approach

We investigate the region of validity of the semiclassical approach to simulating laser cooling. We conclude that for the commonly used pi(x) pi(y) polarization-gradient configuration, the semiclassical approach is valid only for transitions with recoil parameters epsilon(r), on the order of 10(-4) or less. For the standard laser-cooling transitions only the transitions in Rb and Cs satisfy this condition. For the Doppler and sigma(+)sigma(-) polarization-gradient configuration the semiclassical approach is valid for most of the commonly used transitions; however, the expected gain in execution speed compared with quantum Monte Carlo calculations has been realized only in part. A drastic reduction in calculation time is to be expected by implementing an analytical approach to the long-term contribution of the diffusion coefficient. (c) 2005 Optical Society of America

Козацькі могили у творчості Тараса Шевченка

The detoxification of ammonia occurs mainly through conversion of ammonia to urea in the liver via the urea cycle and glutamine synthesis. Congenital portosystemic shunts (CPSS) in dogs cause hyperammonemia eventually leading to hepatic encephalopathy. In this study, the gene expression of urea cycle enzymes (carbamoylphosphate synthetase (CPS1), ornithine carbamoyltransferase (OTC), argininosuccinate synthetase (ASS1), argininosuccinate lyase (ASL), and arginase (ARG1)), N-acetylglutamate synthase (NAGS), Glutamate dehydrogenase (GLUD1), and glutamate-ammonia ligase (GLUL) was evaluated in dogs with CPSS before and after surgical closure of the shunt. Additionally, immunohistochemistry was performed on urea cycle enzymes and GLUL on liver samples of healthy dogs and dogs with CPSS to investigate a possible zonal distribution of these enzymes within the liver lobule and to investigate possible differences in distribution in dogs with CPSS compared to healthy dogs. Furthermore, the effect of increasing ammonia concentrations on the expression of the urea cycle enzymes was investigated in primary hepatocytes in vitro. Gene-expression of CPS1, OTC, ASL, GLUD1 and NAGS was down regulated in dogs with CPSS and did not normalize after surgical closure of the shunt. In all dogs GLUL distribution was localized pericentrally. CPS1, OTC and ASS1 were localized periportally in healthy dogs, whereas in CPSS dogs, these enzymes lacked a clear zonal distribution. In primary hepatocytes higher ammonia concentrations induced mRNA levels of CPS1. We hypothesize that the reduction in expression of urea cycle enzymes, NAGS and GLUD1 as well as the alterations in zonal distribution in dogs with CPSS may be caused by a developmental arrest of these enzymes during the embryonic or early postnatal phase

Quality of life after coronary bypass:a multicentre study of routinely collected health data in the Netherlands†

OBJECTIVES: In this study, our aim was to explore how coronary artery bypass grafting affects quality of life, and how this varies with age, particularly with patients at risk of deterioration. METHODS: In a retrospective, multicentre cohort study, patients with isolated coronary artery bypass grafting and electively operated between January 2011 and January 2015 with pre- and postoperative quality-of-life data were included. Patients were classified into 3 age groups: <65, 65-79 and ≥80 years. Quality of life was measured up to 1-year follow-up using the Short Form-12 or the Short Form-36 health survey. A multivariable, linear regression analysis, with an adjustment for confounders, was used to evaluate the association between age and quality of life. RESULTS: A total of 2606 patients were included in this study. Upon one-year of follow-up, the mean physical health of patients increased from 54 at baseline to 68, and mental health increased from 60 to 67. We observed decreased mental health in 20% of patients aged <65 years, 20% of patients aged 65-79 years and 29% of patients aged ≥80 years (P = 0.039). In this study, age was not associated with a lower physical or mental component score (P = 0.054 and P = 0.13, respectively). Independent risk factors for a decrease in quality of life consist of a better physical and mental score at baseline (P < 0.001) and a reduced left ventricular function (P < 0.001). CONCLUSIONS: Most patients experience a relevant increase in physical and mental quality of life, but a proportion of patients aged ≥80 years undergo significant deterioration in mental health

Middle East respiratory syndrome coronavirus specific antibodies in naturally exposed Israeli llamas, alpacas and camels

Thus far, no human MERS-CoV infections have been reported from Israel. Evidence for the circulation of MERS-CoV in dromedaries has been reported from almost all the countries of the Middle East, except Israel. Therefore, we aimed to analyze MERS-CoV infection in Israeli camelids, sampled between 2012 and 2017. A total of 411 camels, 102 alpacas and 19 llamas' sera were tested for the presence of antibodies to MERS-CoV. Our findings indicate a lower MERS-CoV seropositivity among Israeli dromedaries than in the surrounding countries, and for the first time naturally infected llamas were identified. In addition, nasal swabs of 661 camels, alpacas and lamas, obtained from January 2015 to December 2017, were tested for the presence of MERS-CoV RNA. All nasal swabs were negative, indicating no evidence for MERS-CoV active circulation in these camelids during that time period

Two-component spike nanoparticle vaccine protects macaques from SARS-CoV-2 infection

Brouwer et al. present preclinical evidence in support of a COVID-19 vaccine candidate, designed as a self-assembling two-component protein nanoparticle displaying multiple copies of the SARS-CoV-2 spike protein, which induces strong neutralizing antibody responses and protects from high-dose SARS-CoV-2 challenge.The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is continuing to disrupt personal lives, global healthcare systems, and economies. Hence, there is an urgent need for a vaccine that prevents viral infection, transmission, and disease. Here, we present a two-component protein-based nanoparticle vaccine that displays multiple copies of the SARS-CoV-2 spike protein. Immunization studies show that this vaccine induces potent neutralizing antibody responses in mice, rabbits, and cynomolgus macaques. The vaccine-induced immunity protects macaques against a high-dose challenge, resulting in strongly reduced viral infection and replication i

From surgical waste to medical products

Hospital waste has a major impact on the environment. The worldwide growth of hospital waste is the result of the growing world population and the increase in use of disposables. A circular healthcare economy may contribute to the reduction of hospital waste. The circular economy is a system in which waste is prevented and where waste is reused.This thesis reports the findings of circular methods and strategies.Medical Instruments & Bio-Inspired Technolog