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On the integro-differential equations with reflection
El Hadi Ait Dads
Safoua Khelifi

El Hadi Ait Dads

and 2 more

May 02, 2020
There are a few purely periodic phenomena in nature, which allows one to consider several other generalizations, such as almost automorphic and measure pseudo almost automorphic oscillations. In this paper, by developing important properties on the composition of functions with reflection, using some exponential dichotomy properties and an application of the fixed-point theorem, several new sufficient conditions for the existence and the uniqueness of an pseudo almost automorphic solutions with measure for some general type reflection integro-differential equations. We suppose that the nonlinear part is measure pseudo almost automorphic and in which we distinguish the two constant and variable cases for the lipschitz coefficients of the functions associated with this part. It is assumed that the linear part of the equation considered admits an exponential dichotomy. Finally, an application is given on the very interesting model of Markus and Yamabe.
Global existence and nonexistence of solutions to the Cahn-Hilliard equation with var...
Van Chuong Quach
Le Cong Nhan

Van Chuong Quach

and 2 more

May 02, 2020
This paper deals with a Cahn-Hilliard equation with variable exponent sources. By using the potential well method, we give some threshold results on existence and nonexistence of global weak solutions when initial data with energy less than the potential well depth $d$. In the former case, we also show the exponential decay properties of energy functional. We finally obtain some sufficient conditions for the global existence and non-global existence results with high energy initial data. The results of this paper extend some recent results of Han (2018) \cite{Han18} and Zhou (2019) \cite{Zhou19} to the case of PDEs with variable exponent sources.
The Step-type Contrast Structure for A Second Order Semi-linear Singularly Perturbed...
Mei Xu
Honghui Yin

Mei Xu

and 1 more

May 02, 2020
The step-type contrast structure for a second order semi-linear singularly perturbed differential-difference equation is studied. Using the methods of boundary function and fractional steps, we construct the formula asymptotic expansion of the problem. At the same time, based on sewing techniques, the existence of the step-type contrast structure solution and the uniform validity of the asymptotic expansion are proved.
Critical exponent for semi-linear structurally damped wave equation of derivative typ...
Ahmad Fino
Tuan Anh Dao

Ahmad Fino

and 1 more

May 02, 2020
The main purpose of this paper is to study the following semi-linear structurally damped wave equation with nonlinearity of derivative type: $$u_{tt}- \Delta u+ \mu(-\Delta)^{\sigma/2} u_t= |u_t|^p,\quad u(0,x)= u_0(x),\quad u_t(0,x)=u_1(x),$$ with $\mu>0$, $n\geq1$, $\sigma \in (0,2]$ and $p>1$. In particular, we are going to prove the non-existence of global weak solutions by using a new test function and suitable sign assumptions on the initial data in both the subcritical case and the critical case.
Entropy optimized Darcy-Forchheimer slip flow of Fe3O4-(CH2OH)2 nanofluid past a stre...
Manoj Nayak
Sachin Shaw

Manoj Nayak

and 1 more

May 02, 2020
The present article reveals the extent of effectiveness available from the investigation on entropy generation, thermal radiation, viscous dissipation on Darcy-Forchheimer convective slip flow of Fe3O4-(CH2OH)2 nanofluid past stretching/shrinking rotating disk subject to suction. The concepts of different parameters and their effects on velocity, temperature, entropy generation number and Bejan number profiles have been elaborated in this explanatory paper. The explanations using graphs and numerical tables help smoothen the understanding and strengthen the interpretations of the results of the study. The major eye-catching outcome of the study is that the augmented slip parameter undermines the tangential velocity and fluid suction invites a diminutive radial velocity as well as temperature distribution due to stretching/shrinking rotating disk. Enhanced Reynolds number peters the entropy generation number out for stretching rotating disk which was the goal of the study to be accomplished.
AUGMENTATION OF HEAT TRANSFER IN A MICROTUBE AND A WAVY MICROCHANNEL USING HYBRID NAN...
Shikhar Singh
Suvanjan  Bhattacharyya

Shikhar Singh

and 4 more

May 02, 2020
The paper discusses the numerical investigation involving forced convective heat transfer (HT) in the laminar flow regime is carried out for nanofluid (NF) and hybrid nanofluid (HNF) in a microtube and wavy microchannel. Water-based Al2O3 nanofluid and water-based Al2O3-Ag hybrid nanofluid is studied for this purpose. Reynolds Number (Re), temperature, volume fraction, and nanoparticle (NP) size are varied for the analysis at a constant heat transfer rate. Numerical results characterizing the performances of nanofluid and hybrid nanofluid are presented in terms of the local heat transfer coefficient. It is found that with the increase in Reynolds number, volume fraction and temperature, local heat transfer coefficient is increased. Comparison of nanofluid and hybrid nanofluid reveals superior heat transfer property of the later. However, microtube exhibits better heat transfer coefficient than the wavy channel at constant heat flux, length and area.
Unguided research and noncompliance may have intensified the COVID-19 pandemic
Farid Rahimi
Amin Talebi Bezmin Abadi

Farid Rahimi

and 1 more

May 02, 2020
In February 2020, WHO officially named the novel coronavirus disease as the Coronavirus disease 2019 (COVID-19), and on March 11, proclaimed it a pandemic. The daily increasing number of cases infected with COVID-19 has distressed people and alarmed health authorities worldwide. While no prophylactic vaccine or effective drug for COVID 19 exists, the pandemic is mainly managed by avoidance strategies. We posit that two factors may have accelerated the propagation of the pandemic. First, undertaking unguided research may have negatively influenced the intervention measures against the pandemic. Second, noncompliance with timely in-house isolation of infected cases has undoubtedly worsened the pandemic. Successful management of the pandemic highly depends on the cumulative knowledge about the virus.
A case of biatrial thrombus in a patient with mitral stenosis presenting as systemic...
HARSHWARDHAN KHANDAIT
Vinod Khandait

HARSHWARDHAN KHANDAIT

and 2 more

May 02, 2020
Rheumatic heart disease is a sequelae of rheumatic fever. Mitral stenosis in rheumatic heart disease is common and leads to left atrial dilation and atrial fibrillation. Atrial fibrillation predisposes to thrombus formation in the left atrium and its appendage and is associated with embolic complications. Systemic embolism is frequent and associated with considerable mortality, especially in the developing world. Pulmonary embolism is rarely documented. Herein we report an extremely rare case of biatrial thrombus in a patient with rheumatic heart disease presenting as systemic as well as pulmonary embolism. Keywords: rheumatic, biatrial, thrombus, embolism
Ectopic olfactory receptors in human: New therapeutic possibilities
Rifat Nowshin Raka
Hua Wu

Rifat Nowshin Raka

and 6 more

May 02, 2020
The distributions of olfactory receptors (ORs) are widely available throughout our body, not compartmentalized in nasal parts, which are known as Ectopic olfactory receptors (EORs). Their functions are diverse but the majority of them are yet to be determined. ORs in non-olfactory tissues transduce their signals via different pathways that vary depending on their placements. As they are G-protein coupled receptors (GPCR), they stimulate Golf protein following the activation with specific ligands. They are involved in several cellular processes like chemotaxis, tissue repairing, hair growth, cell proliferation, energy metabolism, inflammation, apoptosis, etc. All these functions make them prospective therapeutic targets. The transformed expression level of ORs in the healthy and cancerous cells might open a new door to detect and diagnose cancer in the early stages. Ligand-based activation can also block the cancer pathway. This review summarizes the therapeutic potential of the EORs including their manifold functions outlined till date.
To what extent have key recommendations from the Getting It Right First Time programm...
William Gray
Jamie Day

William Gray

and 3 more

May 02, 2020
Rationale, aims and objectives: The Getting It Right First Time (GIRFT) programme was set up to reduce unwarranted variation in healthcare practice and outcomes in England. The aim of this study was to investigate early changes in practice in urology based on the recommendations made. Key recommendations included: 1) to increase rates of day-case surgery for transurethral resection of bladder tumour (TURBT), 2) to reduce use of stenting as a primary procedure for emergency presentations with ureteric stones and 3) to reduce waiting times for male bladder outflow tract surgery following emergency presentation with urinary retention. Methods: Data on patient age, the treatment provider, dates of admission and discharge, diagnoses and procedures conducted were extracted from the Hospital Episodes Statistics database from January 2014 to December 2019. The dates of visits by members of the GIRFT team was taken as the intervention point. Interrupted time series analysis was used to identify trends pre- and post-intervention. Results: There was evidence of a significant increase in the proportion of patients seen as day-cases for TURBT and decreased use of stents and increased use of ureteroscopy or extracorporeal shock-wave lithotripsy on first presentation with ureteric stones following GIRFT visits. However, there was no significant change in waiting times for surgery to treat patients who had an emergency presentation with urinary retention. Conclusions: In the first 18 months following the last of the GIRFT visits, there is some evidence that the recommendations made are already having an impact on clinical practice. The reasons why some recommendation appear to be harder to implement requires further investigation.
An unusual cause of heart failure in postoperative Tetralogy of Fallot
GURBHEJ SINGH
Arun Gopalakrishnan

GURBHEJ SINGH

and 2 more

May 02, 2020
The long term results of Tetralogy of Fallot (TOF) repair have been good, pulmonary regurgitation and consequent right ventricular dilatation is the most common long term sequel of definitive surgery. Even in such a setting, overt systemic venous congestion is limited to the rare setting where right ventricular dysfunction sets in due to deferred surgery or progressive arrhythmia. Here we report a unique case where a patient developed right heart failure from an unexpected etiology 14 years after TOF repair.
Association of lymph node promotion activity to cervical lymph node yield of oral can...
Ching-Chieh Yang
Bor-Hwang  Kang

Ching-Chieh Yang

and 4 more

May 02, 2020
Objectives: High quality of lymph node yield could increase survival but strategies to improve it was seldom reported. This study was aim to assess the impact of a lymph node promotion activi-ty (LNPA) in oral cancer surgery through a difference-in-differences research design. Design: A retrospective based study. Setting: Medical center in Taiwan. Subjects and methods: A total of 400 oral cancer patients underwent primary tumor resection and neck dissection including elective neck dissection (END) and radical neck dissection (RND) were recruited after propensity score matching by clinical T and N category between 2009 Janu-ary and 2018 October. Oral cancer patients were treated by two independent departments in our institute. Since 2015 Oct, a LNPA was initiated in one department (target group), and another department was as a control group. The impact of LNPA on LN yield and regional recurrence were analyzed and compared between these two groups by difference-in-differences (DID) linear regression analysis. Results: The mean age was 55.2+11.1 years, and 92% were male. 180 (45%) oral cancer patients had T3-4 disease, and 128 (32%) patients had N2-3 disease. In DID analysis, a lower LN yield among the target group before 2015 Oct (coefficient=-11.05, p<0.001). LNPA launched after 2015 Oct in target group showed a positive promotion of LN yield (coefficient=13.24, p<0.001). Moreover, a borderline protective effect of LNPA on regional recurrence among those with cN0 disease (coefficient= -9.4%, p=0.087) was noted. Conclusion: Strategy, like LNPA was associated increased LN yield and decreased regional re-currence in oral cancer. This kind of activity to promote surgeons to improve their quality of neck dissection was feasible and could be applied widespread.
Causality assessment of adverse drug reactions detected in a Brazilian public hospita...
Renata Menezes
Maria das Dores Silva

Renata Menezes

and 6 more

May 02, 2020
Adequate categorization of adverse drug reaction (ADR) causality may contribute to its early recognition in the assessment of ADR. The method proposed by World Health Organization and Uppsala Monitoring Center (WHO-UMC system) is universally used for causality assessment. We sought to evaluate ADR causality in hospitalized patients using WHO-UMC system. ADR preventability was also evaluated in this study. We reviewed cases of ADR identified in a Brazilian university hospital. Three healthcare professionals adjudicated, independently, each ADR reported using WHO-UMC method. Overall, 90 ADR involving 64 patients were evaluated and adjudicated as possible in 47 (52.2%) cases. Slight concordance was found in the agreement analyses, with kappa range of 0.10-1.18, indicating poor reproducibility of WHO-UMC system. Our results suggest the involvement of interdisciplinary teams could improve the quality of the monitoring process of ADR. A great number of preventable ADR reinforce the need for improvements in pharmacovigilance strategies in hospital settings.
Ensuring Bi-Directional Cavo-Tricuspid Isthmus Conduction Block During Ablation for T...
Gregory Feld

Gregory Feld

May 02, 2020
This editorial will review the new pacing method described by the authors in this issue of the journal that they propose to ensure bi-directional cavo-tricuspid isthmus (CTI) conduction block after radiofrequency catheter ablation in patients with CTI dependent atrial flutter.
Patients' Experience after Cryoballoon Ablation Under Moderate Sedation and General A...
Youssef Jalloul
Marwan Refaat

Youssef Jalloul

and 1 more

May 02, 2020
In 1999, Paul Myles et al. published an important paper outlining the details of a novel assessment tool to measure patients’ quality of recovery (QoR) post-anesthesia and surgery.[1] The following year, Paul Myles et al. published another article outlining the QoR-40. This study, as well as multiple other studies, further studied QoR-40’s validity, reliability, internal consistency, test-retest reliability, inter-rater reliability, and split-half coefficient.[1–3] It can be completed in a relatively short period (around five minutes).[3,4] However, its administration by the investigators provides more complete and timely data as compared to self-administration.[4] It has been translated into multiple languages and validated by these languages as well.[5] However, even though the QoR-40’s score has a maximum score of 200 with a range of 160, the minimal clinically important difference is only 4.8 units to translate into clinically relevant change. The difference between the mean QoR-40 scores post-cardiac surgery (with and without complications) was only four units while maintaining a wide standard deviation within groups.[5,6] QoR’s utility lies in its correlation with patient satisfaction as well as with another measure of patient well-being, the quality of life (QoL) score.[3] Furthermore, the QoR-40’s score three days post-cardiac surgery correlated well with the SF-36’s measure of QoL 3 months after the operation. Hence QoR-40 is helpful in assess patient’s short-term prognosis.[7] These findings hold even three years after the operation; however, the correlation level does decrease. [8]In this issue of the journal of cardiovascular electrophysiology, Wasserlauf et al. utilized the QoR-40 to measure the impact of the anesthesia used during cryoballoon ablation of paroxysmal atrial fibrillation.[9] Catheter ablation has become a common procedure for the management of paroxysmal atrial fibrillation with minor procedural complication. [10,11] Patients undergoing cryoballoon ablation for atrial fibrillation experience less pain than radiofrequency ablation. [12]Multiple sedative modalities can be utilized for cardiac catheter ablation. One modality is the use of a light anesthetic: It alerts the physician of patient discomfort, it comforts the physician and nursing staff and carries a lower risk of drug overdose. However, it does increase the patients’ intraoperative motion.[13] Other modalities include general anesthesia and deep sedation. However, it should be noted that conscious sedation does carry a risk of hypoventilation and aspiration. [14] In a previous study, no significant difference in complication rate was present following ventricular tachycardia ablation during minimal as compared to deep sedation. [15] Also, in another study, patients undergoing percutaneous epicardial access (for ventricular tachycardia or premature ventricular complex) had similar complication rates regardless of whether they did the procedure under general anesthesia or moderate/deep sedation. [16] Furthermore, in a study by Tang et al., patients who underwent non-conscious sedation during catheter ablation for atrial fibrillation had more transient anesthetic complications as compared to conscious sedation. However, these two groups did not reveal a difference in the procedure-related complication/success rates. [17] Finally, Wasserlauf et al. found moderate sedation to carry a lower procedure time without jeopardizing the complication and recurrence rate up to a median follow-up duration of 0.9 years. This paper studied patients undergoing cryoballoon ablation for paroxysmal atrial fibrillation. [18]Given the previously reported evidence supporting the use of conscious anesthesia during atrial fibrillation catheter ablation, Wasserlauf et al. set on a task to expand our knowledge of patients’ tolerance of moderate sedation during cryoballoon ablation. [9] Consequently, they studied patients undergoing cryoballoon ablation for paroxysmal atrial fibrillation under general anesthesia or moderate sedation. Within 24 hours after the procedure, patients would provide the QoR-40 and their likelihood to recommend the procedure and sedation method. The mean QoR-40 was greater than 180 in the two groups with a difference of less than 5 unites. Furthermore, the difference in the QoR-40 scores was not statistically significant. [9] These scores were better than scores observed by Myles in minor surgeries (178 ± 17) and cardiac surgeries without complications (176 ± 16). [6] Moreover, patients reported a high satisfaction rate with a high likelihood to recommend the procedures (83% and 89%) and a high likelihood to recommend the sedation method (94% and 85%) depending on the sedation method (general anesthesia and moderate sedation respectively). However, the difference was not statistically significant.[9] This result is similar to a previous study that found that 96% of patients would recommend radiofrequency ablation for atrial fibrillation.[19] What these results mean is that they support the use of moderate sedation as compared to general anesthesia, given the similar patient experience, but different procedure time, expense, and possible complications from general anesthesia. [9]This study, however, does have limitations. It was a single-center non-randomized study. The QoR-40 has sections that are heavily dependent on the medical center and staff; hence this is an important issue to consider. Furthermore, the assignment to anesthesia groups was not standardized, and the decision was dependent on physician and patient preference. Though understandable, the physician preference can be made to be dictated by a predefined set of criteria to minimize nonrandom assignment. Finally, we note that the QoR-40 scores presented by Wasserlauf et al. were the means and standard deviations. [9] When calculating the 95% confidence intervals of the difference of the mean QoR-40 scores of the two groups, we find that there is no statistically significant difference between the two groups.In conclusion, Wasserlauf et al. have added to our knowledge of cryoballoon ablation under moderate sedation which might become the more frequently adopted anesthesia strategy during AFib cryoablation.References:1. Myles PS, Hunt JO, Nightingale CE, et al. Development and psychometric testing of a quality of recovery score after general anesthesia and surgery in adults. Anesth Analg. 1999;88(1):83-90. doi:10.1097/00000539-199901000-000162. Myles PS, Weitkamp B, Jones K, Melick J, Hensen S. Validity and reliability of a postoperative quality of recovery score: The QoR-40. Br J Anaesth. 2000;84(1):11-15. doi:10.1093/oxfordjournals.bja.a0133663. Gornall BF, Myles PS, Smith CL, et al. Measurement of quality of recovery using the QoR-40: A quantitative systematic review. Br J Anaesth. 2013;111(2):161-169. doi:10.1093/bja/aet0144. Gower ST, Quigg CA, Hunt JO, Wallace SK, Myles PS. A comparison of patient self-administered and investigator-administered measurement of quality of recovery using the QoR-40. Anaesth Intensive Care. 2006;34(5):634-638. doi:10.1177/0310057x06034005145. Myles PS. Measuring quality of recovery in perioperative clinical trials. Curr Opin Anaesthesiol. 2018;31(4):396-401. doi:10.1097/ACO.00000000000006126. Myles PS. Clinically Important Difference in Quality of Recovery Scores. Anesth Analg. 2016;122(1):13-14. doi:10.1213/ANE.00000000000010607. Myles PS, Hunt JO, Fletcher H, Solly R, Woodward D, Kelly S. Relation between quality of recovery in hospital and quality of life at 3 months after cardiac surgery. Anesthesiology. 2001;95(4):862-867. doi:10.1097/00000542-200110000-000138. Myles PS, Viira D, Hunt JO. Quality of life at three years after cardiac surgery: Relationship with preoperative status and quality of recovery. Anaesth Intensive Care. 2006;34(2):176-183. doi:10.1177/0310057x06034002209. Wasserlauf, Jeremiah; Kaplan, Rachel; Walega, David; Arora, Rishi; Chicos, Alexandr; Kim, Susan; Lin, Albert; Verma, Nishant; Patil, Kaustubha; Knight, Bradley; Passman R. Patient-Reported Outcomes After Cryoballoon Ablation Are Equivalent Between Moderate Sedation And General Anesthesia. J Cardiovasc Electrophysiol. 2020.10. Chung MK, Refaat M, Shen WK, Kutyifa V, Cha YM, Di Biase L, Baranchuk A, Lampert R, Natale A, Fisher J, Lakkireddy DR. Atrial Fibrillation: JACC Council Perspectives. J Am Coll Cardiol. Apr 2020; 75 (14): 1689-1713.11. D’Avila A, Ptaszek LM, Yu PB, Walker JD, Wright C, Noseworthy PA, Myers A, Refaat M, Ruskin JN: Left Atrial-Esophageal Fistula After Pulmonary Vein Isolation. Circulation May 2007; 115(17): e432-3.12. Attanasio P, Huemer M, Shokor Parwani A, et al. Pain Reactions during Pulmonary Vein Isolation under Deep Sedation: Cryothermal versus Radiofrequency Ablation. PACE - Pacing Clin Electrophysiol. 2016;39(5):452-457. doi:10.1111/pace.1284013. Defaye P, Kane A, Jacon P, Mondesert B. Cryoballoon for pulmonary vein isolation: Is it better tolerated than radiofrequency? Retrospective study comparing the use of analgesia and sedation in both ablation techniques. Arch Cardiovasc Dis. 2010;103(6-7):388-393. doi:10.1016/j.acvd.2010.06.00414. Calkins H, Kuck KH, Cappato R, et al. 2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: Recommendations for Patient Selection, Procedural Techniques, Patient Management and Follow-up, Definitions, Endpoints, and Research Trial Design. Heart Rhythm. 2012;9(4):632-696.e21. doi:10.1016/j.hrthm.2011.12.01615. Wutzler A, Mueller A, Loehr L, et al. Minimal and deep sedation during ablation of ventricular tachycardia. Int J Cardiol. 2014;172(1):161-164. doi:10.1016/j.ijcard.2013.12.17516. Killu AM, Sugrue A, Munger TM, et al. Impact of sedation vs. general anaesthesia on percutaneous epicardial access safety and procedural outcomes. Europace. 2018;20(2):329-336. doi:10.1093/europace/euw31317. Tang RB, Dong JZ, Zhao W Du, et al. Unconscious sedation/analgesia with propofol versus conscious sedation with fentanyl/midazolam for catheter ablation of atrial fibrillation: A prospective, randomized study. Chin Med J (Engl). 2007;120(22):2036-2038. doi:10.1097/00029330-200711020-0001818. Wasserlauf J, Knight BP, Li Z, et al. Moderate Sedation Reduces Lab Time Compared to General Anesthesia during Cryoballoon Ablation for AF Without Compromising Safety or Long-Term Efficacy. PACE - Pacing Clin Electrophysiol. 2016;39(12):1359-1365. doi:10.1111/pace.1296119. Ezzat VA, Chew A, McCready JW, et al. Catheter ablation of atrial fibrillation - Patient satisfaction from a single-center UK experience. J Interv Card Electrophysiol. 2013;37(3):291-303. doi:10.1007/s10840-012-9763-5
Protecting the Esophagus During Catheter Ablation: Evaluation of a Novel Vacuum Sucti...
Mohamad El Moheb
Marwan Refaat

Mohamad El Moheb

and 1 more

May 02, 2020
Catheter ablation is the current standard of care for the management of symptomatic atrial fibrillation (AFib) refractory to pharmacological therapy. One of the complications of this procedure is thermal injury to the esophagus due to its anatomical proximity to the posterior wall of the left atrium (1). Rarely (<1%), an atrioesophageal fistula can form connecting the lumen of damaged esophagus to the atrial chamber (2). This complication is almost always fatal and can result in exsanguination, air embolism, and sepsis (3, 4). With a growing number of catheter ablations being performed each year, the rate of atrioesophageal fistulas is only expected to rise (5). Other more frequent complications include esophageal wall erosions and ulcers (47%), and thermal injury to the vagus nerve plexus leading to esophageal dysmotility and gastroparesis (17%) (6, 7). Therefore, protecting the esophagus from thermal injuries is paramount in ablative procedures and several strategies have been devised to help mitigate this risk. Many physicians monitor the luminal esophageal temperature (LET) [ as a surrogate for intramural esophageal tissue temperature] with a single sensor or multisensor temperature probe and interrupt energy delivery when LET reaches 38°C or 39°C during radiofrequency ablation. However, this technique significantly impacts the procedural workflow due to the waiting periods for LET to return to baseline. Alternative strategies involve cooling of the esophagus with ice water or reducing the ablation lesion power, contact force and/or duration but this strategy may increase the chances for pulmonary vein reconnection (8). To that end, there has been a growing interest in mechanical devices capable of deflecting the esophagus away from the atrium protecting it from thermal injury.In the current issue of the Journal of Cardiovascular Electrophysiology, Houmsse et al. introduce a novel device capable of mobilizing the esophagus laterally to protect it from injury when performing catheter ablation for AFib. Although other devices have been developed and/or used for this purpose (such as the transesophageal echocardiography probe, endotracheal stylet, Esosure stylet and DV8 shaped balloon retractor), this is the only one to operate using vacuum suction allowing it to latch onto the esophageal wall. The device consists of four main components: outer extrusion, inner stacking plates, deflecting arm and control handle. The outer extrusion is inserted via a trochanter or a bougie into the esophagus and is the only portion of the retractor that comes in contact with the surrounding tissues. Small perforations at the distal end allow for vacuum suction to adhere to the esophagus and for a radiocontrast agent to be delivered to delineate the esophageal contour. The inner stacking plates are then introduced through the outer extrusion and are designed to allow movement of the deflecting arm in the medio-lateral plane only. The deflecting arm is connected to the distal end of the stacking plates through a pivot point and can be steered using the control handle. The authors have evaluated the effectiveness and safety of the device on canine and swine animal models by measuring the distance and direction of displacement of the esophagus, examining the cellular architecture after prolonged suction, measuring the LET, and assessing compatibility of device with electroanatomical mapping systems. A total of 68 deviations were performed on four canine models. The average rightward deflection was equal to 26.6 ± 2.5mm compared to 18.7 ± 2.3mm for the direct leftward deflection (p<0.001), and 96% of deviations did not have an esophageal trailing edge. With the exception of one study, the average distance displaced using the suction retractor was superior to other devices (9-13). The substantial distance of deflection and the minimal esophageal trailing edge significantly decreased the rise in LET from baseline (mean increase of 0.2°C vs 2.5°C without deflection). Examination of the esophageal tissue integrity following one hour of continuous suctioning revealed no change in the esophageal cellular architecture, and only minimal circular areas of hyperemia in mucosa due to the suction ports without injury to the muscularis layer. Finally, the retractor did not interfere with the electroanatomical mapping systems used (CARTO and EnSite).Despite its interesting findings, this study has several limitations that should be acknowledged. First, the study was performed on swine and canine animal models, which are known to have an anatomy close to humans; however, the safety profile of the device and its effectiveness in displacing the esophagus may not translate in humans. Second, subjects may exhibit symptoms secondary to extreme deviation of the esophagus in the absence of distortion of the cellular architecture. Clinical studies are needed to assess the safety profile and side effects of this esophageal retractor. Third, it is unclear whether these results would be reproducible under monitored anesthesia care. Finally, the fluoroscopic equipment tools lacked electronic caliper capabilities, and the measurements were performed using radiopaque rulers.Overall, the authors should be commended on their efforts to introduce and evaluate an inexpensive and innovative tool for esophageal protection during AFib ablation. This retractor addresses the limitations of other products that serve a similar purpose. In fact, the suctioning power of the product minimizes the trailing edge of the esophagus that could not be managed with other devices which left esophageal tissue in the ablation field (10, 13). In addition, the control handle offers significant flexibility in device manipulation allowing physicians to choose the site of angulation and the angle of deflection depending on the patient’s anatomy. Future studies should focus on evaluating the safety and effectiveness of this device in humans. Given the growing number of esophageal retracting devices, studies should also aim to determine the device that produces the best esophageal protection and most desirable outcomes of ablation.REFERENCES1. Chung MK, Refaat M, Shen WK, Kutyifa V, Cha YM, Di Biase L, Baranchuk A, Lampert R, Natale A, Fisher J, Lakkireddy DR. Atrial Fibrillation: JACC Council Perspectives. J Am Coll Cardiol. Apr 2020; 75 (14): 1689-1713.2. D’Avila A, Ptaszek LM, Yu PB, Walker JD, Wright C, Noseworthy PA, Myers A, Refaat M, Ruskin JN. Left Atrial-Esophageal Fistula After Pulmonary Vein Isolation. Circulation May 2007; 115(17): e432-3.3. Aryana A, Arthur A, O’ Neill PG, D’Avila A. Catastrophic manifestations of air embolism in a patient with atrioesophageal fistula following minimally invasive surgical ablation of atrial fibrillation. Journal of cardiovascular electrophysiology. 2013;24(8):933-4.4. Stöckigt F, Schrickel JW, Andrié R, Lickfett L. Atrioesophageal fistula after cryoballoon pulmonary vein isolation. Journal of cardiovascular electrophysiology. 2012;23(11):1254-7.5. Oral H, Siontis KC. Prevention of Atrioesophageal Fistula After Catheter Ablation: If the Esophagus Cannot Stand the Heat (Cold), Can It Be Moved to the Sidelines? : JACC: Clinical Electrophysiology; 2017.6. Shah D, Dumonceau J-M, Burri H, Sunthorn H, Schroft A, Gentil-Baron P, et al. Acute pyloric spasm and gastric hypomotility: an extracardiac adverse effect of percutaneous radiofrequency ablation for atrial fibrillation. Journal of the American College of Cardiology. 2005;46(2):327-30.7. Schmidt M, Nölker G, Marschang H, Gutleben K-J, Schibgilla V, Rittger H, et al. Incidence of oesophageal wall injury post-pulmonary vein antrum isolation for treatment of patients with atrial fibrillation. Europace. 2008;10(2):205-9.8. Tran VN, Kusa S, Smietana J, Tsai W-C, Bhasin K, Teh A, et al. The relationship between oesophageal heating during left atrial posterior wall ablation and the durability of pulmonary vein isolation. Ep Europace. 2017;19(10):1664-9.9. Mateos JCP, Mateos EIP, Peña TGS, Lobo TJ, Mateos JCP, Vargas RNA, et al. Simplified method for esophagus protection during radiofrequency catheter ablation of atrial fibrillation-prospective study of 704 cases. Brazilian Journal of Cardiovascular Surgery. 2015;30(2):139-47.10. Bhardwaj R, Naniwadekar A, Whang W, Mittnacht AJ, Palaniswamy C, Koruth JS, et al. Esophageal Deviation During Atrial Fibrillation Ablation: Clinical Experience With a Dedicated Esophageal Balloon Retractor. JACC Clin Electrophysiol. 2018;4(8):1020-30.11. Herweg B, Johnson N, Postler G, Curtis AB, Barold SS, Ilercil A. Mechanical esophageal deflection during ablation of atrial fibrillation. Pacing and clinical electrophysiology. 2006;29(9):957-61.12. Palaniswamy C, Koruth JS, Mittnacht AJ, Miller MA, Choudry S, Bhardwaj R, et al. The extent of mechanical esophageal deviation to avoid esophageal heating during catheter ablation of atrial fibrillation. JACC: Clinical Electrophysiology. 2017;3(10):1146-54.13. Parikh V, Swarup V, Hantla J, Vuddanda V, Dar T, Yarlagadda B, et al. Feasibility, safety, and efficacy of a novel preshaped nitinol esophageal deviator to successfully deflect the esophagus and ablate left atrium without esophageal temperature rise during atrial fibrillation ablation: The DEFLECT GUT study. Heart Rhythm. 2018;15(9):1321-7.
Barriers to multidisciplinary team approach in end-of-life decision-making: Insights...
Jaydeep Sengupta
Suhita Chopra Chatterjee

Jaydeep Sengupta

and 1 more

May 02, 2020
A common perception about Multidisciplinary team (MDT) approach is that it improves quality of care to hospitalized patients, particularly those who are dying. However, there is paucity of information on challenges in implementing such approach in end-of-life care (eolc). The present study explores barriers to MDT functioning in the context of ‘eolc’. Data collected through interviews of physicians, nurses and other staff, and review of case records of deceased patients of a multispecialty hospital in Kolkata (India) suggest that the MDT approach fails to live up to its rhetoric. One of the major challenges is professional boundary that is intrinsic to MDT. Due to this, specialist physicians fail to make consensus end-of-life decisions by overcoming disciplinary boundaries. Moreover, holistic caregiving is compromised in the physician-dominant medical team, where nurses and other non-clinical caregivers feel marginalized. The hospital environment is also not conducive to multidisciplinary teamwork. Application of a disease-specific treatment protocol in ‘eolc’ settings aggravates team coordination. ‘Eolc’ referrals and care transfers becomes very difficult. Dying patients and their families are specially affected by such discordant care. Based on the findings, the study suggests that while team approach is imperative to effective ‘eolc’, there is a need to shift focus from multidisciplinary to transdisciplinary approach to enhance care integration and patient-centric care to terminally ill patients.
Occupation-based practice: Developing a new instrument
Ilande Vorster
Helen Buchanan

Ilande Vorster

and 2 more

May 02, 2020
Rationale and objective: Occupation-based practice (OBP) is a treatment approach unique to occupational therapy. It harnesses the power of occupation to achieve health and well-being. Most hand therapists are occupational therapists, however, current hand therapy treatment methods are component-based, focussing on physical impairments. This is despite an emerging body of evidence that supports the effectiveness of OBP with hand conditions. To explore the use of OBP in hand therapy, the knowledge, attitudes and practices (KAP) of South African occupational therapists towards OBP needed to be first established. There was no contextually-relevant instrument for this, thus this paper reports on the development processes of a new instrument to capture KAP in OBP in South African hand therapists. Method: Questionnaire development followed the Burns et al (2008) methodology. Items were identified following a comprehensive literature search. Face and content validity, clinical utility, and validation of the subsequent Afrikaans translation were undertaken by two purposively-selected sets of participants (experts and peers). Data collection involved cognitive interviewing, iterative email correspondence, face-to-face discussions, and member checking. Final adjustments to questionnaire wording were made through consensus discussion between the first and second authors. Results: Four therapists participated. Seventy-nine questionnaire items were retained, with three items being removed as they were unclear, or did not measure constructs appropriately for context. The final survey instrument had face and content validity and consisted of 63 KAP items and 16 demographic questions. Conclusion: This is believed to be the first instrument designed to capture valid information on KAP in OBP in hand therapy in South Africa. It will assist in identifying gaps in practice quality, and underpin design of effective strategies for education about, and implementation of, OBP within hand therapy. The instrument is suitable for adaptation to other fields of occupational therapy practice in South Africa, and internationally.
Treepie Dendrocitta vagabunda parvula (Passeriformes: Corvidae) as a natural enemy of...
saira bibi
fiaz khan

saira bibi

and 2 more

May 02, 2020
In district Haripur, KPk, Pakistan Treepie Dendrocitta vagabunda parvula (Latham, 1790) (Passeriformes: Corvidae), is a widespread resident bird commonly found. Feeding and Food habits of Treepie were studied by direct focal observation method analysis of gut content and faecal matter. Treepie prefers tree and cultivation areas insects for foraging activities, feeding on animal and plant is an omnivore items ranging from vertebrate species to invertebrate. Feeding upon like red palm weevil, grasshopper, cockroaches, banana stem weevil, nestlings of squirrel and house rat, it feeds up on many pests of agricultural crops Treepie is an important biocontrol agent in the agro ecosystem of the region
Assessment of Eustachian Tube Function in Patients With Chronic Otitis Media With Eff...
Lingxue Zhang
Shan Liu

Lingxue Zhang

and 4 more

May 02, 2020
Objective: To explore the pathogenesis of Eustachian tube dysfunction (ETD) in patients with chronic otitis media with effusion (COME) using middle ear pressure-equilibration testing. Methods: Pressure equilibration testing of ET ventilation function was carried out in 72 ears which included 51 ears of COME patients with ventilation tube (COME group) and 21 ears of patients with traumatic tympanic perforation (TP group). According to the results of the test, these ears were further divided into four types: 1. with both passive and active opening, 2. only with passive opening, 3. only with active opening, 4. without passive and active opening. Results: 85.7% ears in the TP group had both active and passive ET function while 88.2% ears in the COME group had ETD. The average frequency of ET opening (P<0.001) and the occurrence rate of pressure rebound wave (P<0.001) was significantly lower in the COME group, while the mean residual pressure after several swallowing acts (P<0.001) and the average ET opening duration (P=0.004) was significantly higher in the COME group than in the TP group. Conclusions: Relatively higher residual pressure, lower effective opening frequency, disappearance of rebound wave and longer ET opening duration indicate poor ET ventilation function and an abnormal contraction pattern of peritubular muscles of the ET in patients with COME. Our results show that ETD is prevalent in most patients with COME with various causes. Therefore, appropriate treatment methods should be adopted to ensure prompt and adequate recovery. Keywords: Eustachian tube function,pressure-equilibration test,chronic otitis media with effusion
Process economics evaluation of cell-free synthesis for the commercial manufacture of...
Christos Stamatis
Suzanne Farid

Christos Stamatis

and 1 more

May 02, 2020
Continuous improvements of cell-free synthesis (CFS) systems have generated interest in adopting the technology for the manufacture of biologics. This paper provides an evaluation of the manufacturing cost-effectiveness of CFS for a range of commercial scenarios. The evaluation was performed using an advanced techno-economic engine (TEE) built in Python. The TEE is programmed in an object-oriented environment capable of simulating a plethora of process flowsheets and predicting size and cost metrics for the process and the facility. A case study was formulated to compare the economics of whole bioprocesses based on either a CFS system or a mammalian cell system (CHO) for the manufacture of an antibody drug conjugate (ADC) at different commercial product demand levels (100 – 1000kg/year). The analysis demonstrated the potential of CFS for the commercial manufacture of biologics and identified key cost drivers related with the system. The CFS system showed approximately a two-fold increase in the cost of goods compared to CHO with a significant cost attributed to the in-house manufacture of the bacterial cell extract, necessary for the CFS reaction step in the process. A sensitivity and target analysis highlighted the impetus for further process improvements especially in the titre for the CFS process to become more competitive against well-established systems.
The Ac2-26 peptide of ANXA1 protects against sepsis-induced acute kidney injury by ne...
yanlei zheng
Li Zhu

yanlei zheng

and 4 more

May 02, 2020
A document by yanlei zheng, written on Authorea.
Comment on “ACE inhibitors and COVID-19: We don’t know yet”
Tevfik Ilcol
Erkan Cure

Tevfik Ilcol

and 2 more

May 02, 2020
We read with great interest the article by Khashkhusha TR et al “ACE inhibitors and COVID-19: We don’t know yet”. The authors discuss whether the use of angiotensin-converting enzyme (ACE) inhibitors (ACEIs) in novel coronavirus disease‐19 (COVID‐19) patients is beneficial or harmful. ACEIs and angiotensin receptor antagonists (ARBs) both upregulate ACE2 levels. We believe that ARBs should be preferred since, unlike ARBs, ACEIs may increase angiotensin II through the chymase pathway. We would like to discuss potential harms ACEI may cause through secondary bradykinin-chymase pathways.
Prognostic Factors for Surgical Margin Status and Recurrence in Partial Nephrectomy
Hüseyin Cihan Demirel
Sedat Çakmak

Hüseyin Cihan Demirel

and 8 more

May 02, 2020
Purpose: To evaluate the prognostic factors affecting surgical margin and recurrence in patients who underwent partial nephrectomy for renal masses. Materials and Methods: Data of 125 patients who underwent open or laparoscopic partial nephrectomy due to renal mass between January 2006 and January 2019 were analyzed retrospectively. Demographic data, habits, additional diseases, clinical and laboratory findings, operational data, the morphology of the tumor in computerized tomography or magnetic-resonance imaging and follow-up data were scanned and acquired via our hospital’s system and archive. Results: Average age was 54.4, male-female ratio was 1.55 and average tumor size was 3.31 cm. 104 patients had malignant pathology and 21 was benign. Positive surgical margin rate was 5.6% and recurrence rate was 3.2%. Average follow-up was 47.4 months. Pathological size of the tumor was larger (p=0.006), warm-ischemia period was lower (p=0.003), and PADUA score was higher (p=0.015) in open technique. Tumor size and tumor stage were statistically higher in patients with recurrence (p=0.009, p<0.001 respectively). No statistically significant difference was observed between surgical margin positivity and tumor size, Fuhrman grades, PADUA scores, R.E.N.A.L. scores, and C-index. (p>0.05) Conclusion: Surgical margin positivity after partial nephrectomy is not significantly associated with tumor characteristics and anatomical scoring systems. Tumor size and stage after partial nephrectomy are valuable parameters in evaluating the recurrence risk. Keywords: nephrectomy, recurrence, margins of excision, prognosis
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