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Rhabdomyoma Association With Atrioventricular Septal Defect in an Infant, A Rare Co-i...
Ilker Mercan
Muhammet Akyuz

Ilker Mercan

and 2 more

April 07, 2020
Cardiac rhabdomyoma is the most common primary heart tumor in childhood. This tumor, which is frequently associated with tuberous sclerosis complex, mostly disappears in childhood with spontaneous regression. Surgical resection is required in case of outflow obstruction, arrhythmia and protruding enough to disrupt the filling of the heart cavities. There are very few case series in the literature about rhabdomyom, whose relationship with other congenital heart defects has not been clearly demonstrated. In this case of tuberous sclerosis we presented to you, we reported our approach to the tumor during the corrective surgery of the infant, who was diagnosed with atrioventricular septal defect and patent ductus arteriosus, and rhabdomyoma accompanying these malformations.
A polyvalent and universal tool for genomic studies in gastropod molluscs (Heterobran...
Juan Moles
Gonzalo Giribet

Juan Moles

and 1 more

April 07, 2020
Molluscs are the second most diverse animal phylum and heterobranch gastropods present ~44,000 species. These comprise fascinating creatures with a huge morphological and ecological disparity. Such great diversity comes with even larger phylogenetic uncertainty and many taxa have been largely neglected in molecular assessments. Genomic tools have provided resolution to deep cladogenic events but generating large numbers of transcriptomes/genomes is expensive and usually requires fresh material. Here we leverage a target enrichment approach to design and synthesize a probe set based on available genomes and transcriptomes across Heterobranchia. Our probe set contains 57,606 70mer baits and targets a total of 2,259 ultra-conserved elements (UCEs). Post-sequencing capture efficiency was tested against 31 marine heterobranchs from major groups, including Acochlidia, Acteonoidea, Aplysiida, Cephalaspidea, Pleurobranchida, Pteropoda, Runcinida, Sacoglossa, and Umbraculida. The combined Trinity and Velvet assemblies recovered up to 2,211 UCEs in Tectipleura and up to 1,978 in Nudipleura, the most distantly related taxon to our core study group. Total alignment length was 525,599 bp and contained 52% informative sites and 21% missing data. Maximum-likelihood and Bayesian inference approaches recovered the monophyly of all orders tested as well as the larger clades Nudipleura, Panpulmonata, and Euopisthobranchia. The successful enrichment of diversely preserved material and DNA concentrations demonstrate the polyvalent nature of UCEs, and the universality of the probe set designed. We believe this probe set will enable multiple, interesting lines of research, that will benefit from an inexpensive and largely informative tool that will, additionally, benefit from the access to museum collections to gather genomic data.
Better than Expected Prognosis of Minimal Tracheal Invasion in Well Differentiated th...
Narin  Nard-Carmel
Dana Amsterdam

Narin Nard-Carmel

and 9 more

April 07, 2020
Background: The aim of this study was to compare outcomes of patients with minimal tracheal invasion undergoing shave resection to other forms of ETE in lieu of the new American Joint Committee on Cancer (AJCC) staging. Methods: All patients diagnosed with well differentiated thyroid cancer (WDTC) and ETE were analyzed. Structural recurrence was measured and compared between various forms of ETE. Results: A total of 132 patients were included in the study. Twenty-seven patients (20.4%) had strap muscle invasion, twenty-two patients (16.7%) had minimal tracheal invasion and 83 patients (62.9%) had other forms of ETE. Kaplan-Meier models for structural recurrence revealed that when combining T3b patients with T4a shave patients and comparing them to other T4a patients, the former performed better than the latter (p=0.028 for all ages; p= 0.021; for patients >55 years). Conclusions: Patients with minimal tracheal may be more correctly staged as T3b rather than T4a.
Better triage tests needed for HPV positive women. (Mini commentary on BJOG-20-0093.R...
Pedro Vieira-Baptista

Pedro Vieira-Baptista

April 07, 2020
Mini-commentary on BJOG-20-0093.R1: The impact of age and high risk human papillomavirus (hrHPV) status on the prevalence of high grade cervical intra-epithelial neoplasia (CIN2+) in women with persistent hrHPV positive, cytology negative screening samples: a prospective cohort study.
Are reproductive traits related to pollen limitation in plants? A case study from a C...
Michael Bartoš
Štepán Janeček

Michael Bartoš

and 7 more

April 07, 2020
The deficiency of pollen grains for ovule fertilization can be the main factor limiting plant reproduction and fitness. Due to ongoing global changes, such as biodiversity loss and landscape fragmentation, a better knowledge of the prevalence and predictability of pollen limitation is challenging within current ecological research. In our study we used pollen supplementation to evaluate pollen limitation (at the level of seed number and weight) in 22 plant species growing in a wet semi-natural meadow. We investigated the correlation between the Pollen Limitation index (PL) and floral traits associated with plant reproduction or pollinator foraging behaviour. We recorded significant pollen limitation for approximately 41% of species (9 out of 22 surveyed). Seven species had a significant positive response in seed production and two species increased in seed weight after pollen supplementation. Considering traits, PL significantly decreased with the number of pollinator functional groups. The relationship of PL with other examined traits was not supported by our results. The causes of pollen limitation may vary among species with regard to 1) different reproductive strategies and life history, and/or 2) temporary changes in influence of biotic and abiotic factors at a site.
The context dependence of non-consumptive predator effects
Aaron Wirsing
Michael Heithaus

Aaron Wirsing

and 4 more

April 07, 2020
Non-consumptive predator effects (NCEs) are now widely recognized for their capacity to shape ecosystem structure and function. Yet, forecasting the propagation of these predator-induced trait changes through particular communities remains a challenge, in part because we lack a predictive framework that accounts for environmental and species context. Accordingly, focusing on plasticity in prey anti-predator behaviors, we conceptualize the multi-stage process by which predators trigger direct and indirect NCEs, review and then distill potential drivers of NCE contingencies into three key categories (properties of the prey, predator, and setting), and conduct a meta-analysis to quantify the extent to which prey behavioral plasticity in response to predation risk hinges on a well-studied driver – prey energetic state. Our synthesis underscores the myriad factors that can generate NCE contingencies while guiding how research might better anticipate and account for them. We highlight two key knowledge gaps that continue to hinder development of a comprehensive framework for exploring non-consumptive predator-prey interactions. These are insufficient exploration of 1) context-dependent indirect NCEs and 2) the ways in which direct and indirect NCEs are shaped interactively by multiple drivers of context dependence.
Anomalous Origin of the Right Coronary Artery from the Left Coronary Sinus in a child...
Neeraj Awasthy

Neeraj Awasthy

April 07, 2020
A 11 year-old boy with no relevant past cardiac history presented with complain of chest pain last 10 days . Electrocardiography showed sinus rhythm incomplete RBBB with no ST –T changes at rest ,Subsequent echo revealed abnormal origin of RCA with normal systolic and diastolic biventricular functions, CT- Coronary angiography finally confirmed the diagnosis and showed abnormal origin of right coronary artery that arose from the left coronary sinus- that has been associated with angina, myocardial infarction, and sudden cardiac death. The incidence of coronary anomalies in patients undergoing coronary angiography varies from 0.64% to 1.3%. Many of these anomalies are clinically benign; however, others are associated with serious morbidity6. We describe the case of a patient in whom evaluation of chest pain revealed an anomalous right coronary artery arising from the left coronary sinus. We discuss the clinical importance of this anomaly and review the literature concerning current views and therapy.
Increase of the lethal activity of Cytotoxic T cells and Natural killer cells as a re...
mohmmed salem
Nehal Elmashad

mohmmed salem

and 3 more

April 07, 2020
Cytotoxic T cells are one of the most specialized immune cells to defend the body against foreign invaders in the best scenario, but failure in the function of these cells, leading to decrease defense of the body against cancer. We aims to address the functionality of cytotoxic T lymphocytes (CTLs), Natural killer (NK) and Natural killer T-cells (NKT) cells in lung cancer patient’s pre and post-stimulation of these cells in-vitro using laboratory activation protocol. Five healthy persons as volunteers and fifteen lung cancer patients were subjected to this study. The count of CTLs, NK and NKT cells and the expression of their intracellular granzyme B (GzB) pre and post-stimulation for 72 hrs in-vitro was determined. The plasma level of cytokines and chemokines was correlated with the patient’s prognosis. Data showed that after culture, there were highly significantly increased in the fold change of the percentage of GzB expression on CD3, CD4, CD8 and NKCD8 T cells in lung cancer patients before induction of chemotherapy when compared to healthy control and other lung cancer patients. The level of Proinflammatory cytokines in patients before and during induction of chemotherapy showed IL-1 and CCL-2 in a 13000, 250 fold increase respectively while it decreases in patients after induction of chemotherapy compared with the control group. Patients before the induction of chemotherapy have the ability to improve their CTL and NK functionality under activation conditions. The use of immune activation mechanisms is needed before the induction of chemotherapy.
High resolution multi-marker DNA metabarcoding reveals sexual dietary differentiation...
Luis Silva
Vanessa Mata

Luis da Silva

and 4 more

April 07, 2020
Although sexual dietary differentiation is well known in birds, it is usually linked with significant morphological dimorphism between males and females, with lower differentiation reported in sexually monomorphic or only slightly dimorphic species. However, this may be an artefact of poor taxonomic resolution achieved in most conventional dietary studies, which may be unable to detect subtle intraspecific differentiation in prey consumption. Here we show the power of multi-marker metabarcoding to address these issues, focusing on a slightly dimorphic generalist passerine, the black wheatear Oenanthe leucura. Using markers from four genomic regions (18S, 16S, COI and trnL), we analysed faecal droppings collected from 93 adult black wheatears during the breeding season. We found that sexes were rather similar in bill and body features, though males had a slightly thicker bill and longer wings and tail than females. Diet was dominated in both sexes by a very wide range of arthropod species and a few fleshy fruits, but the overall diet diversity was higher for males than females, and there was a much higher frequency of occurrence of ants in female (58%) than male (29%) diets. We hypothesise that the observed sexual differentiation was likely related to females foraging closer to their offspring on abundant prey, while males consumed a wider variety of prey while foraging more widely. Overall, our results suggest that dietary sexual differentiation in birds may be more widespread than recognised at present, and that multi-marker DNA metabarcoding is a particularly powerful tool to unveiling such differences.
Investigating characteristics of health-related quality of life in different types of...
David Bächinger
Wilma Grossmann

David Bächinger

and 3 more

April 07, 2020
Objectives: To investigate characteristics of health-related quality of life and evaluate the association between health-related quality of life (HRQoL) and hearing among different types of chronic middle ear diseases (CMED). Design: Prospective longitudinal cohort study. Setting: Tertiary referral centre. Participants: Adult patients undergoing surgical treatment for CMED. Main outcomes measures: Pure-tone audiometry, Zurich Chronic Middle Ear Inventory (ZCMEI-21). Results: A total of 108 patients (55 females, 53 males; mean age 51.0 years [SD 15.9]) were included. CMED included COM with cholesteatoma (epitympanic [n = 39]; pars tensa [n = 7]), persistent mastoid cavity (with recurrent cholesteatoma; n = 15; without recurrent cholesteatoma, n = 10), COM without cholesteatoma (n = 22), revision ossiculoplasty for hearing restoration (n = 14), and postinflammatory meatal fibrosis (n = 1). No significant differences between pre- and postoperative air conduction pure-tone average was observed in any type of CMED. Preoperatively, mean ZCMEI-21 score showed statistically significant differences among different types of CMED (p = 0.007) with persistent mastoid cavity without cholesteatoma exhibiting the highest mean ZCMEI-21 score (34.1, SD 7.7) indicating a poor HRQoL. At a mean follow-up period of 183 days, no statistically significant differences in ZCMEI-21 scores among different types of CMED were observed (p = 0.67). Conclusion: This study objectifies differences in HRQoL among different types of CMED. In types of CMED with indication for functional surgery only, such as persistent mastoid cavity without cholesteatoma or ossiculoplasty, the worst HRQoL was observed. Yet, in these types of CMED, HRQoL guides decision for treatment. Moreover, differences in HRQoL among different types of CMED are not closely associated with hearing, but largely depend on other symptoms, such as tinnitus, discharge or vertigo.
Pharmacologic and genetic inhibition of G6PD activity attenuates right ventricle pres...
Atsushi Kitagawa
Christina Jacob

Atsushi Kitagawa

and 5 more

April 07, 2020
Background and Purpose: Pulmonary hypertension (PH) is a disease of hyperplasia of pulmonary vascular cells. The pentose phosphate pathway (PPP) – a fundamental glucose metabolism pathway – is vital for cell growth. Because treatment for PH is inadequate, our goal was to determine whether inhibition of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the PPP, prevents maladaptive gene expression that promotes smooth muscle cell (SMC) growth, reduces pulmonary artery remodeling, and normalizes hemodynamics in experimental models of PH. Experimental Approach: PH was induced in mice by exposure to 10% oxygen (Hx) or weekly injection of vascular endothelial growth factor receptor blocker (Sugen5416 (SU); 20 mg.kg-1) during exposure to hypoxia (Hx+SU), and in rats by injecting SU, exposure to 3 weeks Hx, and then 5 weeks normoxia. G6PD inhibitor (PDD4091;1.5 mg kg-1) was injected daily during exposure to Hx. We measured right ventricular (RV) pressure and left ventricular (LV) pressure-volume relationships, and gene expression in lungs of normoxic, Hx, and Hx+SU, and G6PD inhibitor-treated, mice and rats. Key Results: RV systolic and end-diastolic pressures were higher in Hx and Hx+SU than normoxic-control mice. Hx and Hx+SU decreased expression of epigenetic modifiers, increased hypomethylation of the DNA, and induced aberrant gene expression in lungs. G6PD inhibition decreased maladaptive expression of genes and SMC growth, reduced pulmonary vascular remodeling, and decreased RV pressures, compared to untreated PH groups. Conclusions and Implications: Inhibition of G6PD efficaciously reduces RV pressure overload in Hx and Hx+SU mice and rats and appears to be a safe pharmacotherapeutic strategy.
NKp30 -- a prospective target for new cancer immunotherapy strategies
Pedro Pinheiro
Gonçalo Justino

Pedro Pinheiro

and 2 more

April 07, 2020
NK cells are an important arm of the innate immune system, and they constitutively express the NKp30 receptor. NKp30-mediated responses are triggered by the binding of specific ligands, such as tumour cell-derived B7-H6, and involve the secretion of cytotoxic mediators TNF-α, IFN-γ, perforins and granzymes. The latter two constitute a target cell-directed response that is critical in the process of immunosurveillance. The structure of NKp30 is presented, focusing on the ligand-binding site, on the ligand-induced structural changes, and on the experimental data available correlating structure and binding affinity. The translation of NKp30 structural changes to disease progression is also reviewed. NKp30 role in immunotherapy has been explored in chimeric antigen receptor T-cell (CAR-T) therapy. However, antibodies or small ligands targeting NKp30 have not yet been developed. The data reviewed unveils the key structural aspects that must be considered for drug design in order to develop novel immunotherapy approaches.
Pathogenesis of Beta-lactam-induced Serum Sickness-Like Reaction: The potential role...
Abdelbaset Elzagallaai
Awatif Abuzgaia

Abdelbaset Elzagallaai

and 4 more

April 07, 2020
Aims: Drug-induced serum sickness-like reactions (SSLRs) are idiosyncratic drug-induced hypersensitivity reactions that occur in susceptible patients 1-3 weeks after exposure to the culprit drug. The pathophysiology of this type of reactions is not well understood and its diagnosis is difficult due to the lack of safe and reliable diagnostic tests for identifying the culprit drug. The lymphocyte toxicity assay (LTA) is an in vitro test used as a diagnostic and investigative tool for drug hypersensitivity reactions (DHRs). In this pilot study, we investigated the pathogenesis of SSLR using the LTA test to evaluate the potential role of reactive drug metabolites in the pathogenesis of SSLR. Methods: Nineteen patients (14 males and 5 females) were recruited to this study. Demographic data was collected form the patents and blood samples were withdrawn from all patients and from 19 healthy controls. The LTA test was performed on all subjects and data is expressed as percentage increase in cell death compared to control (vehicle without the drug). Results: There was a significant (p<0.05) concentration-related increase in cell death in cells isolated from patients as compared to cells from healthy controls when incubated with the drug in the presence of phenobarbitone-induced rat liver microsomes (MICs). Conclusion: This data suggests the initial bioactivation of the drug to a reactive metabolite followed by a toxic response is a key first step in -lactam antibiotic-induced SSLRs. Further research is needed to explore the implications of this data as to the pathogenesis of -lactam antibiotic induced SSLR.
Synthesis of ppy-MgO-CNT nanocomposites for Ultraviolet application
kumanan Bharathi yazhini
xin wang

kumanan Bharathi yazhini

and 3 more

April 07, 2020
Cotton is one of the most important raw materials for textile and clothing production. Compared with some synthetic polymer fibers, the main drawback of cotton fibers is its poor mechanical properties and its high flammability, and therefore it cannot be used for special textiles. Cotton fabrics treated with modern flame-retardant and reinforcement finishes often cannot meet rigid military specifications. polypyrrole-Magnesium oxide (ppy-MgO) and polypyrrole-Magnesium oxide-Carbon nanotube (ppy-MgO-CNT) composites were prepared with various weight ratios by in-situ chemical polymerization method. 1, 2, 3, 4-butane tetracarboxylic acid (BTCA) was used as cross-linking agent in presence of sodium hypophosphite (SHP). The composite sol was coated on cotton fabric using pad-dry-cure technique. The coated cotton fabrics were characterized by SEM, EDAX, XRD, UV-DRS and FT-IR analysis and tested for flame retardant and UPF application. It was found that ppy-MgO-CNT composite was found to be efficient.
Limited liver resection of a giant hepatic hemangioma is based on graft to recipient...
gaofeng Tang
Bing Wang

gaofeng Tang

and 3 more

April 07, 2020
Aims: Major or limited liver resection of giant benign or malignant tumor is clinically challenging relating residual liver volume to. Here we reported a case of limited liver resection basing on graft to recipient weight ratio. Methods: A giant hepatic hemangioma was detected in a 36 year-old female patient using ultrasound and computerized tomography. His normal liver to total volume ratio was about 20%. We calculated that her remnant liver to body weight ratio was 1.61%, sufficient to support her body, so limited liver resection was conducted. Results: The patient went through a uneventful recovery, she was discharged home 11 days after liver resection and has been well on regular followup. Conclusions: Limited liver resection is feasible in technique following graft to recipient weight ratio.
Cutaneous findings in children and adolescents with attention deficit and hyperactivi...
Nihal Altunisik
Ilknur Ucuz

Nihal Altunisik

and 2 more

April 07, 2020
Background/Aim: Attention Deficit and Hyperactivity Disorder (ADHD) is the most frequently diagnosed psychiatric disorder in children. Only one study was found in literature which examined cutaneous findings in ADHD so far. The aim of the present study is to evaluate the cutaneous findings of children and adolescents diagnosed with ADHD and to compare the incidence of these findings with healthy controls. Methods: Forty-six patients diagnosed with ADHD according to The Diagnostic and Statistical Manual of Mental Disorders fifth edition (DSM-V) criteria and 50 healthy controls with no ADHD symptoms who had similar characteristics to the patient group in terms of sociodemographic characteristics such as age and gender were included in the study. All the patients underwent whole body dermatological examination and pathological findings in the skin, hairy skin and nails in the patient and control group were recorded. Results: The most common finding in the patient group was found as onychophagy and/or periungual skin biting with a rate of 76.1%. In addition, statistically significant difference was found between the two groups in terms of xerosis, prurigo and allergy history. Conclusions: It is important to be careful in terms of cutaneous findings that may accompany ADHD in terms of both early treatment and also for preventing possible complications. In addition, determination of these findings will guide future studies in terms of identifying the common aetiology of ADHD and some cutaneous diseases.
Split Air Conditioners and their role in Airborne Infection Spread.    
Raja Singh

Raja Singh

April 07, 2020
As the World Health Organization denies COVID 19 being airborne in nature, there is some research done by the scientific community which differs in this approach. As prevention is always better than cure, it is always safe to give the benefit of doubt to prevention. Even as more data begins to be available regarding COVID, there is proven spread of airborne disease like tuberculosis being transmitted by this route. As the summer months approach, there will be increased use of Air Conditioners in the tropical regions of the world. India, too being in this part of the world sees an active rise in the indoors which are being air conditioned to meet the thermal comfort requirements of the rising urban population which is spending a large chunk of time indoors. This is coupled with the enforced lockdown which encourages people to stay indoors to prevent the spread of infection. In such situations the use of Split air conditioner requires rethinking as they re-circulate the indoor air without any Fresh air supply into the room. To reduce heat gain and save the electric load of the Split AC, people tend to seal the windows further. This requires some rethought by professionals.
Methane and Carbon Dioxide in Dual-Porosity Organic Matter: Molecular Simulations of...
Eliska Rezlerova
John Brennan

Eliska Rezlerova

and 2 more

April 07, 2020
The manuscript describes a computational study that provides molecular-level insight into shale gas adsorption and transport in shale rocks, which are composed of organic and inorganic matter. Atomistic simulations were used to generate realistic models of the organic matter structures with both micro- and mesoporosity, and correspond to mature and overmature type-II kerogens. These porous material models are unique to most other previous kerogen models since they contain other components (asphaltene/resin, hydrocarbons and carbon dioxide/water fractions) that are typically not modeled. The inclusion of these additional components significantly influences the resulting porous structure characteristics. The adsorption and diffusion behavior of methane (as a shale gas proxy) and methane/carbon dioxide mixtures were simulated in the model structures. Several key industrial-relevant findings are described in the manuscript.
How to avoid nosocomial spread during Tracheostomy for Covid-19 patients
Authorea

Yi Zhong et al.

April 06, 2020
As the novel coronavirus (Covid-19) globally spreads, the Covid-19 pandemic is straining healthcare workers worldwide. In hospitalized patients with severe Covid-19, endotracheal intubation is one of the most common and indispensable life-saving interventions. For patients in need of long-term endotracheal intubation, tracheostomy may be considered. Some patients with unfavorable neck anatomy, such as short neck, enlarged thyroid, and neck cicatricial contracture, are not suitable for percutaneous tracheostomy, a minimally invasive method1. In these circumstances, conventional open tracheostomy is the primary option for surgeons. However, it is one of the most hazardous procedures, because the direct airway opening and the coughing of patients causes aerosolization of the virus potentially exposing healthcare workers2. To prevent healthcare-associated infections, we are willing to share our modified tracheostomy procedures with other surgeons worldwide.Detailed optimized procedures are illustrated in Figure 1. There are three distinct steps to protect healthcare workers from the virus spreading in the surgical environment during tracheostomy. First, all procedures should under general anesthesia, with deprivation of spontaneous respiration and application of muscle relaxants (Figure 1A), regardless of whether patients had spontaneous breathing or not. This step is to restrain the cough reflex caused by tracheal stimulation. Second, after the cervical trachea is exposed and immediately before an incision is made in the trachea, the endotracheal tube (ETT) is inserted deeper, positioned with the tip close to carina of the trachea (Figure 1B). This step would prevent the ETT cuff leak due to an accidental damage to the cuff when making the tracheal opening. Third, when the opening is complete, brief interruption of the ventilator is essential. Then the ETT is pulled out, and subsequently the tracheostomy tube quickly inserted into the opening (Figure 1C). Almost simultaneously, the tracheostomy tube cuff is inflated and the tube rapidly connected to the ventilator, with immediate resumption of the ventilator (Figure 1D). Suspension of ventilation support was usually not more than 15 seconds, with satisfactory oxygen saturation.This report describes the optimized procedures in tracheostomy for Covid-19 patients. The three major modifications can avoid the aerosolization of secretions, and protect healthcare workers. Thus, we strongly recommend the modified procedures to be a choice for all surgeons when tracheostomy is considered for Covid-19 patients. It is important to protect healthcare workers from coronavirus during the intraoperative period for their own health and for preservation of the healthcare workforce.Figure
There is no routine head and neck exam during  the COVID-19 pandemic
Authorea

Jason Y K Chan et al.

April 06, 2020
On March 27, 2020, the Center for Disease Control reported that 85,356 individuals in the United States were infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – exceeding, for the first time, the number of cases in Wuhan, China, where the pandemic began in November, 2019. US federal, state and local agencies are facing an unprecedented public health emergency. The scale of the pandemic has never been seen in US; the way forward uncertain.In 2003, the Hong Kong SAR (HK) healthcare system was thrust into a similar crisis, responding to an outbreak of SARS coronavirus 1 (SARS-CoV-1), that developed in Guangdong Province, China late in 2002. Lessons from how HK physicians adapted their practices to this new disease may hold important lessons for the many countries now facing the pandemic .Based upon experience and evidence from SARS-CoV-1 and early-experience with SARS-CoV-2, we provide our perspective and guidance on mitigating transmission risk during head and neck examination, upper airway endoscopy, and head and neck mucosal surgery including tracheostomy. We set out below, recommendations that every physician performing head and neck examination should consider. The goal is to protect healthcare workers (HCW), caregivers, patients, and the community at large in this Personal Protective Equipment (PPE) limited environment, while conforming to their local guidelines.Early on in the 2003 SARS epidemic, the risk of nosocomial spread of infection to HCW posed a critical challenge. At the Prince of Wales Hospital, HK, a single infected patient caused an outbreak, of which over 50% were HCW, devastating human resources to treat and contain the infection . Seventeen years later HK was inflicted with SARS-CoV-2 late January 2020. A benefit of SARS-COV-1 in HK HCW has been the modus operandi since 2003: including wearing surgical masks in hospital wards, wearing gowns and surgical masks in outpatient clinics and scrubs only in the operating room. The resultant individual and institutional appreciation of infection control measures have served HK well in the current pandemic, relative to other countries, with no HCW COVID-19 nosocomial infections to date 1.In the 2003 SARS-CoV-1 outbreak in HK, an otolaryngologist died after being infected during a routine head and neck examination. In 2020, the first COVID-19 physician fatality was an otolaryngologist in Wuhan, China. Patients with COVID-19 caused by SARS-CoV-2 can carry high viral load in the nasal cavity, nasopharynx, and throat. The anatomic viral distribution of these SARS-CoV viruses in the nasopharynx and mucosal airways, coupled with these disquieting cases, indicate that head and neck examinations and procedures must be approached cautiously with thoughtful preparation and protections. HCW who have these exposures are at heightened risk of transmission.In the outpatient setting, all non-essential clinic visits should be transitioned to virtual “video-visits” or postponed. This will reduce the number of patients in the clinic, minimizing patient flow and potential contamination and freeing up valuable medical resources. On March 18, 2020, the Center for Medicare and Medicaid Services in the US released recommendations to postpone all non-essential dental exams and procedures until further notice.Within the clinic, separate gown up and down areas must be designated to prevent cross-contamination. Visual guides and mirrors for self-visualization in these areas on the steps involved in gowning up and gowning down have, from past experience, proven extremely useful particularly for gowning down, where most HCW self-contaminate (Figure 1). Another critical area is the bedside examination of patients. Currently, there are no CDC guidelines on respiratory and aerosol-generating procedures within the scope of the head and neck surgery, but our experience with SARS-CoV-1 highlights that these are potentially high-risk examinations. Therefore, in HK, there is official guidance for Otolaryngology departments to label several common head and neck examination and procedures as having a potential risk of aerosol generation. This designation carries implications on PPE allocations of as seen in table 1.Anesthetic practices vary but local anesthetic is commonly administered via aerosolized spray in the head and neck examination and procedures. This practice has been abandoned in HK since the SARS-COV-1 epidemic and must be avoided in the current COVID-19 environment. Aerosol spray should be replaced by topical local anesthetic on pledgets or dripped via syringe. Table 1 shows guidelines of PPE use within the outpatient clinic with a dedicated endoscopy room, including flexible laryngoscopy - one of the most common procedures performed in head and neck examination. Unless there is gross contamination there is no need to change the gown, mask or eye protection between each patient.For inpatient rounds, all physicians are recommended to wear a surgical mask and scrubs which are changed daily prior to leaving the hospital. Patient visitors to the hospital should be severely restricted, and visiting hours cut, to minimize people flow and maintain social distancing.For all operative procedures, intubation represents an aerosol-generating procedure as first learned during the 2003 SARS-COV-1 epidemic. Therefore, during intubation anyone in the operating room should have appropriate PPE including a fit-tested N95 mask. This should similarly apply to all open airway procedures such as direct laryngoscopy where they may be a leak during ventilation, tracheostomy, or laryngectomy.Tracheostomies for patients with known COVID-19 should be delayed where possible to minimize viral shedding from the patient, as we know from SARS-COV-1, delaying the tracheostomy does not negatively impact the patient. Guidance for a safe tracheostomy emerged from the 2003 epidemic. The following should be considered for tracheostomies in the COVID-19 pandemic:PPE: AAMI level 3 or waterproof apron on top of AAMI level I isolation gown, N95 mask, face shield, waterproof cap and disposable shoe covers. Powered air purifying respirators (PAPR) may be needed in cases with high viral load.Minimize personnel: One intensivist, one surgeon, one nursing member.Procedure: Use a negative pressure operating room. The patient should be completely paralyzed and preoxygenated. Stop ventilation before tracheotomy and only resume once tracheostomy tube balloon cuff is inflatedPost procedure: Gown down safely, and shower.Ideally, the procedure should be done in a negative pressure operating room with senior personnel and not used as a training procedure. Cautery use should be limited as this can produce small particles that may act as a vehicle for the virus . Again, gowning down following the procedure is of utmost importance and is often overlooked. Dry runs prior to the actual procedure may also help reduce errors and prevent the contamination of HCW.For patients with a tracheostomy they should all be covered with a closed system (Figure 2) identical to when a patient is connected to a mechanical ventilator to minimize the aerosol generated that could cross contaminate the surrounding patients and HCW given the suction requirements of these patients . Humidified tracheostomy collars and nebulized therapies must be avoided. All bedside procedures should be performed in a separate treatment room away from patient cubicles with all HCW wearing PPE. The requirements for PPE will be the same as in the outpatient clinic.In summary, with the use of these broad guidelines which reduces the number of procedures and patients seen, coupled with an appreciation that the head and neck examination cannot be taken lightly in the current pandemic, the risk of exposure and contamination in clinics of patients, HCW and in particular, physicians performing a head and neck examination should be reduced.
Managing  the Head and Neck Cancer Patient with  Tracheostomy or Laryngectomy During...
Authorea

Maxwell P. Kligerman et al.

April 06, 2020
Subtitle: A Review of the Literature and Recommendations for Risk ReductionFull author listMaxwell P. Kligerman, MD, MPH1,2; Neelaysh Vukkadala, MD1,2; Raymond K Y Tsang, FRCS Ed (ORL) MS3; John B. Sunwoo, MD1; F. Christopher Holsinger, MD1; Jason Y K Chan, FRCS Ed (ORL)4; Edward J. Damrose, MD, MPH1,2; Ann Kearney, CScD CCC-SLP, BCS-S2; Heather M. Starmer, MA, CCC-SLP, BCS-S11 Division of Head and Neck Surgery, 2 Division of Laryngology Department of Otolaryngology, Stanford University, Palo Alto, California, U.S.A., 3 Department of Otorhinolaryngology—Head and Neck Surgery, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong SAR, 4 Division of Otorhinolaryngology – Head and Neck Surgery, Department of Surgery, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR
Molecular phylogenetic analysis of wild Tulipa species (Liliaceae) present in Kosovo,...
Avni Hajdari
Bledar Pulaj

Avni Hajdari

and 5 more

April 06, 2020
Species of the genus Tulipa L. (Liliaceae) are characterized with a high variability of vegetative and floral characters, which makes the taxonomy of this genus difficult. In Kosovo the genus Tulipa is represented by eight taxa, which sometimes have been synonymized, erroneously identified, or misclassified. To investigate the phylogenetic relationships of Tulipa species originated from Kosovo, ITS and trnL-trnF DNA sequences were used. In total 55 sequences (29 ITS and 26 trnL-trnF), obtained from 14 taxa were analysed. Forty one sequences were newly generated from eight taxa collected from wild population in Kosovo and 14 sequences were obtained from GenBank. Neighbor-Joining, Maximum Parsimony and Maximum Likelihood trees from independent (ITS and trnL-trnF) and combined (ITS + trnL-trnF) datasets were conducted in PAUP. Based on sequence analyses, our sequences of Tulipa species grouped into two main clades, belonging to the subgenera Eriostemones and Tulipa, respectively. There is not sufficient genetic evidence to distinguish species of the T. scardica complex (T. scardica, T. serbica, T. albanica, T. kosovarica and T. luanica) as independent taxa. Despite the lower resolution of the trnL-trnF than the ITS dataset, both loci do not support the separation of taxa of the T. scardica complex as independent species.
Flame Synthesis of Pd-TiO2 Nanocomposite Catalyst for Oxygen Removal from CO2-rich St...
Sungyoon Jung
Nathan Reed

Sungyoon Jung

and 3 more

April 06, 2020
Pd-TiO2 catalysts with five Pd loadings were synthesized using a flame aerosol reactor. Their initial and changed catalytic properties and kinetic characteristics during/for O2 removal with CH4 were investigated. Different Pd loadings affected the size of Pd sub-nano clusters/nanoparticles and the speciation fraction of Pd (metallic Pd, PdO and PdOx (0〈x〈1)). Increased size of Pd nanoparticles on catalysts’ surface due to sintering and the reduction of PdO to metallic Pd or/and PdOx were observed during the reaction. Fractions of the total surface area of Pd species were calculated, and correlations to the apparent reaction rate constants were established. Apparent kinetic constants were linearly proportional to fractions of total surface areas of metallic Pd or/and reduced Pd oxide were revealed, representing the intrinsic active site. The linear correlation between the O2 reaction rate and the CO2 concentration in the initial gas stream was also observed due to an autocatalytic reaction effect.
Prediction of chromatographic behaviors with Langmuir-artificial neural network adsor...
Shoujiang Li
Shaoyan Wang

Shoujiang Li

and 1 more

April 06, 2020
In order to accurately predict the complex chromatographic behaviors of the components to be separated, by the combination of the Langmuir adsorption formula and the back propagation-artificial neural network (BP-ANN), Langmuir-BP-ANN adsorption model was established. Herein, based on a series of different traditional adsorption isotherms such as with or without competition, one or two kinds of adsorbed sites, monomolecular or multilmolecular adsorption, and so on, the Langmuir adsorption formula was deduced, where the major adsorption parameter Ci was the function of the component concentration, expressed as matrix forms constructed by BP-ANN and obtained by solving the equilibrium dispersive (ED) chromatography model with the inverse method and genetic algorithm (GA). The Langmuir-BP-ANN model was applied to study chromatographic behaviors of m-cresol and p-cresol on MIL-53 (Al) stationary phase.
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