CFSSP: Chou and Fasman Secondary Structure Prediction server

CFSSP (Chou & Fasman Secondary Structure Prediction Server) is an online protein secondary structure prediction server. This server predicts regions of secondary structure from the protein sequence such as alpha helix, beta sheet, and turns from the amino acid sequence.The output of predicted secondary structure is also displayed in linear sequential graphical view based on the probability of occurrence of alpha helix, beta sheet, and turns. The method implemented in CFSSP is Chou-Fasman algorithm, which is based on analyses of the relative frequencies of each amino acid in alpha helices, beta sheets, and turns based on known protein structures solved with X-ray crystallography. CFSSP is freely accessible via ExPASy server or directly from BioGem tools at http://www.biogem.org/tool/chou-fasman

Changes in Emergency Department Care Intensity from 2007-16: Analysis of the National Hospital Ambulatory Medical Care Survey

Introduction: Emergency departments (ED) in the United States (US) have increasingly taken the central role for the expedited diagnosis and treatment of acute episodic illnesses and exacerbations of chronic diseases, allowing outpatient management to be possible for many conditions that traditionally required hospitalization and inpatient care. The goal of this analysis was to examine the changes in ED care intensity in this context through the changes in ED patient population and ED care provided.Methods: We analyzed the National Hospital Ambulatory Medical Care Survey (NHAMCS) from 2007-2016. Incorporating survey design and weight, we calculated the changes in ED patient characteristics and ED care provided between 2007 and 2016. We also calculated changes in the proportion of visits with low-severity illnesses that may be safely managed at alternative settings. Lastly, we compared ED care received and final ED dispositions by calculating adjusted relative risk (aRR) comparing ED visits in 2007 to 2016, using survey weighted multivariable logistic regression.Results: NHAMCS included 35,490 visits in 2007 and 19,467 visits in 2016, representing 117 million and 146 million ED visits, respectively. Between 2007 and 2016, there was an increase in the proportion of ED patients aged 45-64 (21.0% to 23.6%) and 65-74 (5.9% to 7.5%), while visits with low-severity illnesses decreased from 37.3% to 30.4%. There was a substantial increase in the proportion of Medicaid patients (22.2% to 34.0%) with corresponding decline in the privately insured (36.2% to 28.3%) and the uninsured (15.4% to 8.6%) patients. After adjusting for patient and visit characteristics, there was an increase in the utilization of advanced imaging (aRR 1.29; 95% confidence interval [CI], 1.17-1.41), blood tests (aRR 1.16; 95% CI, 1.10-1.22), urinalysis (aRR 1.22; 95% CI, 1.13-1.31), and visits where the patient received four or more medications (aRR 2.17; 95% CI, 1.88-2.46). Lastly, adjusted hospitalization rates declined (aRR 0.74; 95% CI, 0.64-0.84) while adjusted discharge rates increased (aRR 1.06; 95%CI 1.03-1.08). Conclusion: From 2007 to 2016, ED care intensity appears to have increased modestly, including aging of patient population, increased illness severity, and increased resources utilization. The role of increased care intensity in the decline of ED hospitalization rate requires further study

Skin Necrosis Distal to a Rapid Infusion Catheter: Understanding Possible Complications of Large-bore Vascular Access Devices.

Rapid infusion catheters (RICs) allow expedient conversion of peripheral intravenous (PIV) catheters to peripheral sheaths; however, little is known about potential complications. In this case, a 64-year-old male polytrauma patient had a 20-gauge PIV catheter in the right cephalic vein upsized to an 8.5 French (Fr) RIC without incident during an arrest with pulseless electrical activity (PEA). On RIC post-placement day two, the patient developed edema and ecchymosis extending from the right dorsal mid-hand to the antecubital fossa, just distal to the RIC insertion point. Compartments were soft; the volar surface (including an arterial line location), fingers, and upper arm were normal. The RIC flushed and returned blood appropriately. Ultrasound revealed a noncompressible cephalic vein either related to the catheter or thrombosis, and imaging of the hand showed an ulnar styloid fracture and a minimally displaced triquetral fracture. The RIC was removed immediately. Over the next week, the areas of ecchymosis developed bullae and then sloughed, leaving open wounds extending into the dermis. The patient later expired from unrelated causes. The area and timing of the skin necrosis were highly suspicious for a catheter-associated complication, despite the presence of the arterial line and small distal fractures. The necrosis was potentially due to thrombosis of the superficial venous outflow system, leading to congestion and skin compromise, but we found no similar reports. Alternatively, the catheter may have ruptured the vein and caused a gravity-dependent ecchymosis, but the volar surface was not impacted, and the catheter was functioning properly. The RIC may also have encroached on the arterial space, decreasing flow, but we would have expected distal hand changes. The only published reports we could find on RIC complications involved a lost guide wire, fragmentation of a catheter during placement, and a case of compartment syndrome, raising the question of whether skin necrosis is truly a rare event or simply underreported with the RIC. Although the exact causal relationship remains unknown in our case, RICs should be removed as soon as possible after immediate stabilization

Atmospheric teleconnection mechanisms of extratropical North Atlantic SST influence on Sahel rainfall

Extratropical North Atlantic cooling has been tied to droughts over the Sahel in both paleoclimate observations and modeling studies. This study, which uses an atmospheric general circulation model (GCM) coupled to a slab ocean model that simulates this connection, explores the hypothesis that the extratropical North Atlantic cooling causes the Sahel droughts via an atmospheric teleconnection mediated by tropospheric cooling. The drying is also produced in a regional climate model simulation of the Sahel when reductions in air temperature (and associated geopotential height and humidity changes) from the GCM simulation are imposed as the lateral boundary conditions. This latter simulation explicitly demonstrates the central role of tropospheric cooling in mediating the atmospheric teleconnection from extratropical North Atlantic cooling. Diagnostic analyses are applied to the GCM simulation to infer teleconnection mechanisms. An analysis of top of atmosphere radiative flux changes diagnosed with a radiative kernel technique shows that extratropical North Atlantic cooling is augmented by a positive low cloud feedback and advected downstream, cooling Europe and North Africa. The cooling over North Africa is further amplified by a reduced greenhouse effect from decreased atmospheric specific humidity. A moisture budget analysis shows that the direct moisture effect and monsoon weakening, both tied to the ambient cooling and resulting circulation changes, and feedbacks by vertical circulation and evaporation augment the rainfall reduction. Cooling over the Tropical North Atlantic in response to the prescribed extratropical cooling also augments the Sahel drying. Taken together, they suggest a thermodynamic pathway for the teleconnection. The teleconnection may also be applicable to understanding the North Atlantic influence on Sahel rainfall over the twentieth century

On integrability of one third-order nonlinear evolution equation

We study one third-order nonlinear evolution equation, recently introduced by Chou and Qu in a problem of plane curve motions, and find its transformation to the modified Korteweg - de Vries equation, its zero-curvature representation with an essential parameter, and its second-order recursion operator.Comment: 10 page

Improved Chou-Fasman method for protein secondary structure prediction

BACKGROUND: Protein secondary structure prediction is a fundamental and important component in the analytical study of protein structure and functions. The prediction technique has been developed for several decades. The Chou-Fasman algorithm, one of the earliest methods, has been successfully applied to the prediction. However, this method has its limitations due to low accuracy, unreliable parameters, and over prediction. Thanks to the recent development in protein folding type-specific structure propensities and wavelet transformation, the shortcomings in Chou-Fasman method are able to be overcome. RESULTS: We improved Chou-Fasman method in three aspects. (a) Replace the nucleation regions with extreme values of coefficients calculated by the continuous wavelet transform. (b) Substitute the original secondary structure conformational parameters with folding type-specific secondary structure propensities. (c) Modify Chou-Fasman rules. The CB396 data set was tested by using improved Chou-Fasman method and three indices: Q3, Qpre, SOV were used to measure this method. We compared the indices with those obtained from the original Chou-Fasman method and other four popular methods. The results showed that our improved Chou-Fasman method performs better than the original one in all indices, about 10–18% improvement. It is also comparable to other currently popular methods considering all the indices. CONCLUSION: Our method has greatly improved Chou-Fasman method. It is able to predict protein secondary structure as good as current popular methods. By locating nucleation regions with refined wavelet transform technology and by calculating propensity factors with larger size data set, it is likely to get a better result

GAIT STABILITY DURING DIRECTION CHANGE WALKING WITH T-POLES IN THE ELDERLY

INTRODUCTION: Falls are the leading cause of injury deaths for the elderly and typically occur when this population is forced into an unbalanced condition, such as changing a direction during gait. It is widely accepted that the elderly are more vulnerable to falls due to age-related declines in balance and gait stability (Hahn & Chou, 2003). Therefore, a better understanding of gait stability mechanics during direction changes would be critical in reducing the incidence of falls among the elderly. One of the most insightful ways to assess gait stability is to use the instantaneous orientation of the line that connects the center of pressure (COP) and whole body center of mass (COM). The angles made by the line with respect to horizontal line (COM-COP inclination angles) are characterized by the whole body position with respect to the supporting foot during gait (Chou, 2006). Recently, telescopestyle walking poles (T-poles) were deemed effective in reducing elderly fall risk factors (Yoon, 2007); however, the effect of T-poles on gait stability is still unknown. The purpose of this study was to investigate the effects of T-poles on elderly gait stability using COM-COP inclination angles in both straight and direction change during gait

Spinal column shortening versus revision detethering for recurrent adult tethered cord syndrome: a preliminary comparison of perioperative and clinical outcomes.

OBJECTIVE:Recurrent tethered cord syndrome (TCS), believed to result from tension on the distal portion of the spinal cord, causes a constellation of neurological symptoms. Detethering surgery has been the traditional treatment for TCS. However, in cases of recurrent TCS, there is a risk of new neurological deficits developing, and subsequent retethering is difficult to prevent. Spinal column shortening has been proposed as an alternative technique to reduce the tension on the spinal cord without incurring the morbidity of revision surgery on the spinal cord. The authors compared the perioperative outcomes and morbidity of patients who were treated with one or the other procedure. METHODS:The medical records of 16 adult patients with recurrent TCS who were treated between 2005 and 2018 were reviewed. Eight patients underwent spinal column shortening, and 8 patients underwent revision detethering surgery. Patient demographics, clinical outcomes, and perioperative factors were analyzed. The authors include a video to illustrate their technique of spinal column shortening. RESULTS:Within the spinal column shortening group, no patients experienced any complications, and all 8 patients either improved or stabilized with regard to lower-extremity and bowel and bladder function. Within the revision detethering group, 2 patients had worsening of lower-extremity strength, 3 patients had worsening of bowel and bladder function, and 1 patient had improvement in bladder function. Also, 3 patients had wound-related complications. The median estimated blood loss was 731 ml in the shortening group and 163 ml in the revision detethering group. The median operative time was 358 minutes in the shortening group and 226 minutes in the revision detethering group. CONCLUSIONS:Clinical outcomes were comparable between the groups, but none of the spinal column shortening patients experienced worsening, whereas 3 of the revision detethering patients did and also had wound-related complications. Although the operative times and blood loss were higher in the spinal column shortening group, this procedure may be an alternative to revision detethering in extremely scarred or complex wound revision cases