Neurotoxins from Snake Venom

Found within snake venoms are a variety of toxic and nontoxic proteins. The effects of snake venoms depend on all of the components of that venom. However, the lethal effects are usually related to the most potent toxins found within the venom; the two most toxic proteins found in snake venom are neuro- and cardiotoxins. This article reviews a variety of neurotoxins found in snake venom. The range of neurotoxins present in snake venom is varied and includes: peripheral and noncentral, presynaptic, postsynaptic, potassium-channel inhibiting, muscarinic transmission inhibiting, and anticholinesterase types

When Do Abusive Leaders Experience Guilt?

Purpose: Drawing from the appraisal theory, this paper aims to examine the conditions under which abusive leaders experience guilt and suggests that guilt motivates leaders to help followers. Design/methodology/approach: A scenario study with a sample of 285 hospitality supervisors was used to test the theoretical model. Path analyses were conducted to test the three-way-moderated mediation model. Findings: Results show a three-way interaction among enacted abuse, managerial abuse and agreeableness on the guilt: leaders are more likely to experience guilt over their enacted abusive supervision when they do not perceive their direct manager as abusive and when they are agreeable. Moreover, guilt mediates the relationship between enacted abuse and a leader’s intention to help their followers. Research limitations/implications: This study shows that abusive supervisors pay an emotional cost for their enacted abuse (in terms of guilt). Practical implications: Hospitality organization should assign non-abusive mentors to leaders, especially agreeable ones, to detect and reduce abusive supervision. Originality/value: First, this study addressed the lack of research on the effect of abusive supervision on the abusers by studying the conditions under which abusive leaders experience guilt. Second, this study shows that because of guilt, abusive leaders have a higher intention to help their followers. It explains why abusive leaders can be helpful

Potential and limitations of NARX for defect detection in guided wave signals

Previously, a nonlinear autoregressive network with exogenous input (NARX) demonstrated an excellent performance, far outperforming an established method in optimal baseline subtraction, for defect detection in guided wave signals. The principle is to train a NARX network on defect-free guided wave signals to obtain a filter that predicts the next point from the previous points in the signal. The trained network is then applied to new measurement and the output subtracted from the measurement to reveal the presence of defect responses. However, as shown in this paper, the performance of the previous NARX implementation lacks robustness; it is highly dependent on the initialisation of the network and detection performance sometimes improves and then worsens over the course of training. It is shown that this is due to the previous NARX implementation only making predictions one point ahead. Subsequently, it is shown that multi-step prediction using a newly proposed NARX structure creates a more robust training procedure, by enhancing the correlation between the training loss metric and the defect detection performance. The physical significance of the network structure is explored, allowing a simple hyperparameter tuning strategy to be used for determining the optimal structure. The overall detection performance of NARX is also improved by multi-step prediction, and this is demonstrated on defect responses at different times as well as on data from different sensor pairs, revealing the generalisability of this method

Comparison of Sea Snake (Hydrophiidae) Neurotoxin to Cobra (Naja) Neurotoxin

Both sea snakes and cobras have venoms containing postsynaptic neurotoxins. Comparison of the primary structures indicates many similarities, especially the positions of the four disulfide bonds. However, detailed examination reveals differences in several amino acid residues. Amino acid sequences of sea snake neurotoxins were determined, and then compared to cobra neurotoxins by computer modeling. This allowed for easy comparison of the similarities and differences between the two types of postsynaptic neurotoxins. Comparison of computer models for the toxins of sea snakes and cobra will reveal the three dimensional difference of the toxins much clearer than the amino acid sequence alone

Isolation and Chemical Characterization of a Toxin Isolated from the Venom of the Sea Snake, Hydrophis torquatus aagardi

Sea snakes (family: Hydrophiidae) are serpents found in the coastal areas of the Indian and Pacific Oceans. There are two subfamilies in Hydrophiidae: Hydrophiinae and Laticaudinae. A toxin, aagardi toxin, was isolated from the venom of the Hydrophiinae snake, Hydrophis torquatus aagardi and its chemical properties such as molecular weight, isoelectric point, importance of disulfide bonds, lack of enzymatic activity and amino acid sequence were determined. The amino acid sequence indicated a close relationship to the primary structure of other Hydrophiinae toxins and a significant difference from Laticaudinae toxins, confirming that primary toxin structure is closely related to sea snake phylogenecity

Association Between Medication Adherence and the Outcomes of Heart Failure

Background Previous studies of heart failure patients have demonstrated an association between cardiovascular medication adherence and hospitalizations or a composite end point of hospitalization and death. Few studies have assessed the impact of treatment adherence within large general medical populations that distinguish the health outcomes of emergency department visits, hospitalization, and death. Objective To determine the association of incremental cardiovascular medication adherence on emergency department visits, hospitalization, and death in adult heart failure patients in Indiana. Design Retrospective cohort study conducted using electronic health record data from the statewide Indiana Network for Patient Care (INPC) between 2004 and 2009. Methods Patients were at least 18 years of age with a diagnosis of heart failure and prescribed at least one cardiovascular medication for heart failure. Adherence was measured as the proportion of days covered (PDC) using pharmacy transaction data. Clinical end points included emergency department visits, hospital admissions, length of hospital stay, and mortality. Generalized linear models were used to determine the effect of a 10% increase in PDC on clinical end points adjusting for age, sex, race, Charlson comorbidity index, and medications. Results Electronic health records were available for 55,312 patients (mean age ± standard deviation [SD] 68 ± 16 years; 54% women; 65% white). Mean PDC for all heart failure medications was 63% ± 23%. For every 10% increase in PDC, emergency department visits decreased 11% (rate ratio [RR] 0.89; 95% confidence interval [CI] 0.89‐0.89), hospital admissions decreased 6% (RR 0.94; 95% CI 0.94‐0.94), total length of hospital stay decreased 1% (RR 0.99; 95% CI 0.99‐1.00), and all‐cause mortality decreased 9% (odds ratio 0.91; 95% CI 0.90‐0.92). Conclusion Incremental medication adherence was associated with reductions in emergency department visits, hospital admissions, length of hospital stay, and all‐cause mortality

Mortality of Youth Offenders Along a Continuum of Justice System Involvement

Introduction Black male youth are at high risk of homicide and criminal justice involvement. This study aimed to determine how early mortality among youth offenders varies based on race; gender; and the continuum of justice system involvement: arrest, detention, incarceration, and transfer to adult courts. Methods Criminal and death records of 49,479 youth offenders (ages 10–18 years at first arrest) in Marion County, Indiana, from January 1, 1999, to December 31, 2011, were examined. Statistical analyses were completed in November 2014. Results From 1999 to 2011 (aggregate exposure, 386,709 person-years), 518 youth offender deaths occurred. The most common cause of death was homicide (48.2%). The mortality rate of youth offenders was nearly 1.5 times greater than that among community youth (standardized mortality ratio, 1.48). The youth offender mortality rate varied depending on the severity of justice system involvement. Arrested youth had the lowest rate of mortality (90/100,000), followed by detained youth (165/100,000); incarcerated youth (216/100,000); and youth transferred to adult court (313/100,000). A proportional hazards model demonstrated that older age, male gender, and more severe justice system involvement 5 years post-arrest predicted shorter time to mortality. Conclusions Youth offenders face greater risk for early death than community youth. Among these, black male youth face higher risk of early mortality than their white male counterparts. However, regardless of race/ethnicity, mortality rates for youth offenders increase as youth involvement in the justice system becomes more protracted and severe. Thus, justice system involvement is a significant factor to target for intervention

Decreasing delirium through music (DDM) in critically ill, mechanically ventilated patients in the intensive care unit: Protocol for a randomized controlled trial

Background Delirium is a highly prevalent and morbid syndrome in intensive care units (ICUs). Changing the stressful environment within the ICU via music may be an effective and a scalable way to reduce the burden of delirium. Methods/design The Decreasing Delirium through Music (DDM) study is a three-arm, single-blind, randomized controlled feasibility trial. Sixty patients admitted to the ICU with respiratory failure requiring mechanical ventilation will be randomized to one of three arms (20 participants per arm): (1) personalized music, (2) non-personalized relaxing music, or (3) attention-control. Music preferences will be obtained from all enrolled participants or their family caregivers. Participants will receive two 1-h audio sessions a day through noise-cancelling headphones and mp3 players. Our primary aim is to determine the feasibility of the trial design (recruitment, adherence, participant retention, design and delivery of the music intervention). Our secondary aim is to estimate the potential effect size of patient-preferred music listening in reducing delirium, as measured by the Confusion Assessment Method for the ICU (CAM-ICU). Participants will receive twice daily assessments for level of sedation and presence of delirium. Enrolled participants will be followed in the hospital until death, discharge, or up to 28 days, and seen in the Critical Care Recovery Clinic at 90 days. Discussion DDM is a feasibility trial to provide personalized and non-personalized music interventions for critically ill, mechanically ventilated patients. Our trial will also estimate the preliminary efficacy of music interventions on reducing delirium incidence and severity. Trial registration ClinicalTrials.gov, Identifier: NCT03095443. Registered on 23 March 2017

Age-period-cohort analysis of trends in amyotrophic lateral sclerosis incidence

Amyotrophic Lateral Sclerosis (ALS) is a progressive neurodegenerative disease with an unknown cause. Studies have reported that the incidence rate of ALS might be changing. As ALS is an age related disease, crude incidence could increase as population structure changes and overall life expectancy improves. Age-period-cohort (APC) models are frequently used to investigate trends in demographic rates such as incidence. Age-specific incidence rate for ALS from 1996 to 2014 were taken from a population-based ALS register in Ireland. To circumvent the well-known identifiability issue in APC models, we apply the method of Partial Least Squares Regression to separate the effects of Age, Period and Cohort on ALS incidence over time. This APC analysis shows no cohort effect and the initial signs of a period effect; increasing incidence of ALS in the most recently diagnosed group. As further years of data accrue to the Irish register it will become clear if this effect emerges as a strong trend in the incidence of ALS in Ireland and replication of these analyses in other populations will show if our findings on temporal patterns in ALS incidence are shared elsewhere