Sildenafil Protects Endothelial Cells From Radiation-Induced Oxidative Stress.

INTRODUCTION: The etiology of radiation-induced erectile dysfunction (ED) is complex and multifactorial, and it appears to be mainly atherogenic. AIM: To focus on vascular aspects of radiation-induced ED and to elucidate whether the protective effects of sildenafil are mediated by attenuation of oxidative stress and apoptosis in the endothelial cells. METHODS: Bovine aortic endothelial cells (BAECs), with or without pretreatment of sildenafil (5 µM at 5 minutes before radiation), were used to test endothelial dysfunction in response to external beam radiation at 10-15 Gy. Generation of reactive oxygen species (ROS) was studied. Extracellular hydrogen peroxide (H2O2) was measured using the Amplex Red assay and intracellular H2O2 using a fluorescent sensor. In addition, ROS superoxide (O2•-) was measured using a O2•- chemiluminescence enhancer. Both H2O2 and O2•- are known to reduce the bioavailability of nitric oxide, which is the most significant chemical mediator of penile erection. Generation of cellular peroxynitrite (ONOO-) was measured using a chemiluminescence assay with the PNCL probe. Subsequently, we measured the activation of acid sphingomyelinase (ASMase) enzyme by radioenzymatic assay using [14C-methylcholine] sphingomyelin as substrate, and the generation of the proapoptotic C16-ceramide was assessed using the diacylglycerol kinase assay. Endothelial cells apoptosis was measured as a readout of these cells' dysfunction. MAIN OUTCOME MEASURES: Single high-dose radiation therapy induced NADPH oxidases (NOXs) activation and ROS generation via the proapoptotic ASMase/ceramide pathway. The radio-protective effect of sildenafil on BAECs was due to inhibition of this pathway. RESULTS: Here, we demonstrate for the first time that radiation activated NOXs and induced generation of ROS in BAECs. In addition, we showed that sildenafil significantly reduced radiation-induced O2•- and as a result there was reduction in the generation of peroxynitrite in these cells. Subsequently, sildenafil protected the endothelial cells from radiation therapy-induced apoptosis. STRENGTHS AND LIMITATIONS: This is the first study demonstrating that single high-dose radiation therapy induced NOXs activation, resulting in the generation of O2•- and peroxynitrite in endothelial cells. Sildenafil reduced ROS generation by inhibiting the ASMase/ceramide pathway. These studies should be followed in an animal model of ED. CONCLUSIONS: This study demonstrated that sildenafil protects BAECs from radiation-induced oxidative stress by reducing NOX-induced ROS generation, thus resulting in decreased endothelial dysfunction. Therefore, it provides a potential mechanism to better understand the atherogenic etiology of postradiation ED. Wortel RC, Mizrachi A, Li H, et al. Sildenafil Protects Endothelial Cells From Radiation-Induced Oxidative Stress. J Sex Med 2019;16:1721-1733.

Modifications of the National Early Warning Score for patients with chronic respiratory disease.

BACKGROUND: The National Early Warning Score (NEWS) uses physiological variables to detect deterioration in hospitalized patients. However, patients with chronic respiratory disease may have abnormal variables not requiring interventions. We studied how the Capital Region of Denmark NEWS Override System (CROS), the Chronic Respiratory Early Warning Score (CREWS) and the Salford NEWS (S-NEWS) affected NEWS total scores and NEWS performance. METHODS: In an observational study, we included patients with chronic respiratory disease. The frequency of use of CROS and the NEWS total score changes caused by CROS, CREWS and S-NEWS were described. NEWS, CROS, CREWS and S-NEWS were compared using 48-h mortality and intensive care unit (ICU) admission within 48 h as outcomes. RESULTS: We studied 11,266 patients during 25,978 admissions; the use of CROS lowered NEWS total scores in 40% of included patients. CROS, CREWS and S-NEWS had lower sensitivities than NEWS for 48-h mortality and ICU admission. Specificities and PPV were higher. CROS, CREWS and S-NEWS downgraded, respectively, 51.5%, 44.9% and 32.8% of the NEWS total scores from the 'mandatory doctor presence' and 'immediate doctor presence and specialist consultation' total score intervals to lower intervals. CONCLUSION: Capital Region of Denmark NEWS Override System was frequently used in patients with chronic respiratory disease. CROS, CREWS and S-NEWS reduced sensitivity for 48-h mortality and ICU admission. Using the methodology prevalent in the NEWS literature, we cannot conclude on the safety of these systems. Future prospective studies should investigate the balance between detection rate and alarm fatigue of different systems, or use controlled designs and patient-centred outcomes.

Imaging Acetaldehyde Formation During Ethanol Metabolism in Living Cells using a Hydrazinyl Naphthalimide Fluorescent Probe.

The metabolism of ethanol to acetaldehyde has been visualized in living lung epithelial cells using a hydrazinyl naphthalimide fluorescent probe. Utilizing a condensation reaction between carbonyls and a hydrazine moeity, we demonstrate that the fluorescent probe (Aldehydefluor-1) AF1 reacts with a range of reactive carbonyl species including formaldehyde, acetaldehyde, glyoxylic acid, and methyl glyoxal. With AF1, it is possible to directly visualize endogenous carbonyl metabolites. Here, we have applied it towards the visualization of acetaldehyde generated from alcohol dehydrogenase mediated ethanol metabolism, validating it as a useful tool to study the roles of alcohol in respiratory disease and other pathological mechanisms.

Respiratory rates measured by a standardised clinical approach, ward staff, and a wireless device.

BACKGROUND: Respiratory rate is among the first vital signs to change in deteriorating patients. The aim was to investigate the agreement between respiratory rate measurements by three different methods. METHODS: This prospective observational study included acutely admitted adult patients in a medical ward. Respiratory rate was measured by three methods: a standardised approach over 60 s while patients lay still and refrained from talking, by ward staff and by a wireless electronic patch (SensiumVitals). The Bland-Altman method was used to compare measurements and three breaths per minute (BPM) was considered a clinically relevant difference. RESULTS: We included 50 patients. The mean difference between the standardised approach and the electronic measurement was 0.3 (95% CI: -1.4 to 2.0) BPM; 95% limits of agreement were -11.5 (95% CI: -14.5 to -8.6) and 12.1 (95% CI: 9.2 to 15.1) BPM. Removal of three outliers with huge differences lead to a mean difference of -0.1 (95% CI: -0.7 to 0.5) BPM and 95% limits of agreement of -4.2 (95% CI: -5.3 to -3.2) BPM and 4.0 (95% CI: 2.9 to 5.0) BPM. The mean difference between staff and electronic measurements was 1.7 (95% CI: -0.5 to 3.9) BPM; 95% limits of agreement were -13.3 (95% CI: -17.2 to -9.5) BPM and 16.8 (95% CI: 13.0 to 20.6) BPM. CONCLUSION: A concerning lack of agreement was found between a wireless monitoring system and a standardised clinical approach. Ward staff's measurements also seemed to be inaccurate.

End points for validating early warning scores in the context of rapid response systems: a Delphi consensus study.

INTRODUCTION: When investigating early warning scores and similar physiology-based risk stratification tools, death, cardiac arrest and intensive care unit admission are traditionally used as end points. A large proportion of the patients identified by these end points cannot be saved, even with optimal treatment. This could pose a limitation to studies using these end points. We studied current expert opinion on end points for validating tools for the identification of patients in hospital wards at risk of imminent critical illness. METHODS: The Delphi consensus methodology was used. We identified 22 experts based on objective criteria; 17 participated in the study. Each expert panel member's suggestions for end points were collected and distributed to the entire expert panel in anonymised form. The experts reviewed, rated and commented the suggested end points through the rounds in the Delphi process, and the experts' combined rating of the usefulness of each suggestion was established. RESULTS: A gross list of 86 suggestions for end points, relating to 13 themes, was produced. No items were uniformly recognised as ideal. The themes cardiac arrest, death, and level of care contained the items receiving highest ratings. CONCLUSIONS: End points relating to death, cardiac arrest and intensive care unit admission currently comprise the most obvious compromises for investigating early warning scores and similar risk stratification tools. Additional end points from the gross list of suggested end points could become feasible with the increased availability of large data sets with a multitude of recorded parameters.

Chemiluminescent Probes for Imaging H2S in Living Animals.

Hydrogen sulphide (H2S) is an endogenous mediator of human health and disease, but precise measurement in living cells and animals remains a considerable challenge. We report the total chemical synthesis and characterization of three 1,2-dioxetane chemiluminescent reaction-based H2S probes, CHS-1, CHS-2, and CHS-3. Upon treatment with H2S at physiological pH, these probes display instantaneous light emission that is sustained for over an hour with high selectivity against other reactive sulphur, oxygen, and nitrogen species. Analysis of the phenol/phenolate equilibrium and atomic charges has provided a generally applicable predictive model to design improved chemiluminescent probes. The utility of these chemiluminescent reagents was demonstrated by applying CHS-3 to detect cellularly generated H2S using a multi-well plate reader and to image H2S in living mice using CCD camera technology.

Handover of patients: a topical review of ambulance crew to emergency department handover.

Handover has major implications for patient care. The handover process between ambulance and emergency department (ED) staff has been sparsely investigated. The purpose of this paper is, based on a literature review, to identify and elaborate on the major factors influencing the ambulance to ED handover, and to bring suggestions on how to optimize this process. A literature search on handovers to EDs was performed in PubMed, Embase, Web of Science and Cochrane databases. A total of 18 papers were included. Issues regarding transfer of information are highlighted. Newer studies suggest that implementing a structured handover format holds the possibilities for improving the process. Electronic equipment could play a part in reducing problems. Cultural and organizational factors impact the process in different ways. The professions perceive the value and quality of information given differently. Giving and taking over responsibility is an important issue. The handover of patients to the ED has the potential to be improved. Cultural issues and a lack of professional recognition of handover importance need to be approached. Multidisciplinary training in combination with a structured tool may have a potential for changing the culture and improving handover.

A one-day "Helping Babies Breathe" course improves simulated performance but not clinical management of neonates.

OBJECTIVE: "Helping Babies Breathe" (HBB) is a simulation-based one-day course developed to help reduce neonatal mortality globally. The study objectives were to (1) determine the effect on practical skills and management strategies among providers using simulations seven months after HBB training, and (2) describe neonatal management in the delivery room during the corresponding time period before/after a one-day HBB training in a rural Tanzanian hospital. METHODS: The one-day HBB training was conducted by Tanzanian master instructors in April 2010. Two simulation scenarios; "routine care" and "neonatal resuscitation" were performed by 39 providers before (September 2009) and 27 providers after (November 2010) the HBB training. Two independent raters scored the videotaped scenarios. Overall "pass/fail" performance and different skills were assessed. During the study time period (September 2009-November 2010) no HBB re-trainings were conducted, no local ownership was established, and no HBB action plans were implemented in the labor ward to facilitate transfer and sustainability of performance in the delivery room at birth. Observational data on neonatal management before (n=2745) and after (n=3116) the HBB training was collected in the delivery room by observing all births at the hospital during the same time period. RESULTS: The proportion of providers who "passed" the simulated "routine care" and "neonatal resuscitation" scenarios increased after HBB training; from 41 to 74% (p=0.016) and from 18 to 74% (p≤0.0001) respectively. However, the number of babies being suctioned and/or ventilated at birth did not change, and the use of stimulation in the delivery room decreased after HBB training. CONCLUSION: Birth attendants in a rural hospital in Tanzania performed significantly better in simulated neonatal care and resuscitation seven months after one day of HBB training. This improvement did not transfer into clinical practice.

Hydrophobic interaction and charge accumulation at the diamond-electrolyte interface.

The hydrophobic interaction of surfaces with water is a well-known phenomenon, but experimental evidence of its influence on biosensor devices has been lacking. In this work we investigate diamond field-effect devices, reporting on Hall effect experiments and complementary simulations of the interfacial potential at the hydrogen-terminated diamond/aqueous electrolyte interface. The interfacial capacitance, derived from the gate-dependent Hall carrier concentration, can be modeled only when considering the hydrophobic nature of this surface and its influence on the structure of interfacial water. Our work demonstrates how profoundly the performance of potentiometric biosensor devices can be affected by their surfaces' hydrophobicity.

Implementation of team training in medical education in Denmark.

In the field of medicine, team training aiming at improving team skills such as leadership, communication, co-operation, and followership at the individual and the team level seems to reduce risk of serious events and therefore increase patient safety. The preferred educational method for this type of training is simulation. Team training is not, however, used routinely in the hospital. In this paper, we describe a framework for the development of a team training course based on need assessment, learning objectives, educational methods including full-scale simulation and evaluations strategies. The use of this framework is illustrated by the present multiprofessional team training in advanced cardiac life support, trauma team training and neonatal resuscitation in Denmark. The challenges of addressing all aspects of team skills, the education of the facilitators, and establishment of evaluation strategies to document the effect of the different types of training on patient safety are discussed.

Training trauma teams in the Nordic countries: an overview and present status.

BACKGROUND: During the last decade there has been an increased interest in the organisation and quality of trauma care in the Nordic countries. Still, most patients are initially cared for at hospitals with low caseloads of severe trauma. More than 200 hospitals offer initial care to trauma patients. Training of trauma teams using simulators or simulated patients has evolved in the same period, as one important factor to overcome lack of practical training. This overview describes the present state of trauma team training in the Nordic countries. METHODS: Members of a Nordic working group on the use of simulation in medicine reviewed present literature on training with simulation and described the present use of team training in their own countries during winter 2004. RESULTS: There is an increasing amount of evidence indicating that training of teams with simulation reduces treatment errors and improves performance. The training activities do not need to be complex, but skilled debriefing seems necessary. Few Nordic hospitals train their trauma teams. The training activities vary considerably between and within countries. CONCLUSION: There is considerable evidence supporting an increased use of experience gained in other high-risk domains where training in communication, leadership and decision-making is the focus for safety and improvement efforts. There is a need for more widespread training of trauma teams. The different training activities actually undertaken should be scientifically evaluated.

Implementation of team training in medical education in Denmark.

In the field of medicine, team training aiming at improving team skills such as leadership, communication, co-operation, and followership at the individual and the team level seems to reduce risk of serious events and therefore increase patient safety. The preferred educational method for this type of training is simulation. Team training is not, however, used routinely in the hospital. In this paper, we describe a framework for the development of a team training course based on need assessment, learning objectives, educational methods including full-scale simulation and evaluations strategies. The use of this framework is illustrated by the present multiprofessional team training in advanced cardiac life support, trauma team training and neonatal resuscitation in Denmark. The challenges of addressing all aspects of team skills, the education of the facilitators, and establishment of evaluation strategies to document the effect of the different types of training on patient safety are discussed.

Residents lack knowledge and practical skills in handling the difficult airway.

BACKGROUND: Full-scale simulators have been developed in anaesthesia. We aimed at assessing Danish anaesthesia residents' knowledge and management of a standardized difficult airway situation in an advanced airway simulator. The reliability of the assessment was also determined. METHODS: Thirty-six residents answered a questionnaire testing their knowledge on difficult airway management and practice patterns. Secondly, all residents attempted management of a standardized 'cannot ventilate, cannot intubate' airway scenario. Three observers independently assessed a video recording of the performance. RESULTS: Only 17% of the residents passed the written test. Ninety-seven per cent stated that they had difficulties recalling the American Society of Anesthesiologists'(ASA) difficult airway algorithm and 53% did not know how to oxygenate through the cricothyroid membrane. Seventeen per cent had previously been involved in emergency situations with severe complications due to insufficient airway management. In the scenario 75% of the residents established ventilation using a laryngeal mask airway. After establishing ventilation, 26% would continue with surgery without a definitive airway, despite the risk of aspiration. Analysis of the interobserver agreement showed good (Kappa = 0.63) to excellent (Kappa = 0.78) consistency for objective parameters in the scoring scheme. Inter-observer reliability was satisfactory (R = 0.43) for trained Crisis Resource Management evaluators. CONCLUSIONS: Theoretical and practical education in difficult airway management needs to be improved among Danish anaesthesia residents. Simulator assessment should only be performed using well-defined objective parameters and trained assessors.

A retrospective study of the use of total parenteral nutrition in dogs and cats.

The records of all dogs and cats receiving total parenteral nutrition (TPN) over a 43-month period were examined retrospectively. Dextrose, amino acids, lipids, electrolytes, and vitamins were administered by central venous catheter according to published nutrient recommendations; 72 dogs and 12 cats were studied, accounting for 380 patient days of TPN. Duration of TPN administration was 1-14 days with a mean of 4.5 days. Most animals required TPN because of gastrointestinal dysfunction, and more than half of them gained weight during TPN administration. Mechanical complications were frequent. Metabolic complications, especially lipid and glucose intolerance, were also commonly seen. Septic complications were the least frequently encountered, but resulted in patient morbidity and may have contributed to mortality. Most animals receiving TPN were returned to enteral nutrition and discharged. For critically ill animals unable to tolerate enteral alimentation, TPN can be supportive therapy in the treatment of the primary disease.

[Survey of the availability and utilization of Doppler ultrasound in German-speaking areas]. / Umfrage zur Verbreitung und Anwendung der Dopplersonographie im deutschsprachigen Raum.

The study was performed about the spread and usage of Doppler ultrasound measurements. Standardised questionnaires were sent to the obstetrical departments of 253 universities and teaching hospitals. 59% of the hospitals answered the questions. At the university departments, the method was used regularly. On the average twice the number of patients have been examined compared to the teaching hospitals. The obstetricians in the university departments were more experienced in safety determinations and quality control. Most of the university departments used their own norm curves. When measuring the resistance in the favoured vessels umbilical artery, middle cerebral artery and arcuate arteries, the resistance index (RI) was preferred to the pulsatility Index (PI) in both kinds of hospitals. The most severe pathological findings, zero and reverse flow, occurred with an incidence of more than 2% only in hospitals with less than 500 patients a year, indicating false positive results due to inexperienced physicians. Relevant software is not commercially available; therefore documentation and evaluation of the data was done manually in most of the departments. There are different opinions about the use of Doppler ultrasound as a screening test. However, Doppler ultrasound is seen as a valuable method for diagnosis of hypoxia especially in cases of intrauterine growth retardation and pregnancy-induced hypertension. In the year 2000 the method might be widely used in nearly every small hospital and even in offices. This development without adequate training of the obstetricians might result in a high incidence of false positive results.

Hyponatremia and hyperkalemia associated with idiopathic or experimentally induced chylothorax in four dogs.

Two dogs with idiopathic chylothorax and 2 dogs with experimentally induced (ie, ligation of the cranial vena cava) chylothorax were treated by intermittent thoracic drainage. Of these 4 dogs, 3 that did not have evidence of renal failure had normal or near-normal serum sodium and potassium concentrations before thoracic drainage began, and all 3 developed repeatedly marked hyponatremia and hyperkalemia during thoracic drainage. Another dog became weak and depressed, ostensibly because of hyperkalemia. Serum sodium and potassium concentrations in 1 dog with spontaneous chylothorax returned to normal after chylothorax resolved and thoracic drainage was stopped. The other 3 dogs died or were euthanatized, and the effect of stopping thoracic drainage could not be evaluated. In 3 dogs in which it was measured, normal-to-high plasma cortisol concentration was observed before and after adrenocorticotropin administration, and 2 dogs also had hyperaldosteronemia. Hyponatremia was hypothesized to be caused by sodium loss via thoracic drainage whereas hyperkalemia may have been multifactorial in origin, but probably was attributable, at least, in part to decreased renal potassium clearance.

Changes in adrenal cortisol secretion as reflected in the urinary cortisol/creatinine ratio in dogs.

In Experiment 1, voided urine samples were collected from 12 adult dogs at 0500, 1400, and 2200 hr for 4 days. Cortisol was measured in unextracted urine by radioimmunoassay, creatinine by spectrophotometry, and the cortisol/creatinine ratio (UCCR) was calculated for each sample. There was considerable variation both within and among dogs in UCCR but there was no consistent time of day fluctuation in UCCR. In Experiment 2, these dogs were randomly assigned to 1 of 4 groups. The groups received each of 4 treatments (saline, dexamethasone, ACTH gel, and aqueous ACTH) at 7 day intervals in Latin square design. All urine was collected from 0 through 8 hr. Blood samples were collected at 20 minute intervals from 0 through 8 hr. Plasma cortisol exposure was determined by quantifying area under the curve (AUC). UCCR measurement was shown to differentiate basal from elevated, but not lowered, cortisol secretion. A positive linear relationship between UCCR and AUC was seen for all treatments except dexamethasone. These results indicate that changes in cortisol secretion are reflected in changes in UCCR, but measurement of UCCR may lack sensitivity to differentiate basal from reduced states of cortisol secretion. In Experiment 3, urine was collected daily before and during induction therapy with o,p'-DDD from dogs with pituitary-dependent hyperadrenocorticism. Successful suppression of the adrenal glands was accompanied by a progressive decrease in UCCR. There was considerable variation in the rate of adrenal suppression.

Total parenteral nutrition in clinically normal cats.

Seven clinically normal cats were maintained on total parenteral nutrition (TPN) with nothing given PO for 2 weeks. The TPN solution consisted of a mixture of dextrose, amino acids, soybean oil emulsion, electrolytes, and vitamins. Three cats were fed calories in excess of published maintenance requirements, and they gained some weight, vomited occasionally, had oral ulcerations, and had signs of depression after 10 to 13 days on TPN. Four cats that were not overfed did well clinically and maintained stable body weights. All cats developed anemia and thrombocytopenia to varying degrees during TPN administration and had polyuria and serum triglyceride concentrations higher than normal fasting values. Some cats had changes in liver-specific biochemical variables. Hepatocellular swelling and vacuolation and small intestinal villous atrophy and fusion were the most common histopathologic changes seen after TPN. These changes were reversible when TPN was discontinued and the cats were returned to enteral nutrition.

A turbidimetric method for fibronectin assay in the dog.

An immunoturbidimetric method, using spectrophotometry, for the assay of canine plasma fibronectin concentration was compared with the immunoelectrophoretic method. The spectrophotometric method (S) correlated positively (r = 0.7) and significantly (P less than 0.01) with the immunoelectrophoretic method (I). The regression equation was S = 0.37I + 53. Ninety-five percent confidence levels for the regression line were calculated to allow detection, by spectrophotometry, of plasma fibronectin concentrations outside the normal range.