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Toxoplasmosis, a rare case report that led to a successful pregnancy.
THOMAS NTOUNIS
Sofoklis Stavros

THOMAS NTOUNIS

and 7 more

April 17, 2021
A 19-year-old pregnant patient was diagnosed with primary toxoplasmosis infection. The patient was successfully treated with spiramycin and finally delivered normally a healthy boy. Serological tests for detection of anti-toxoplasma antibodies along with ultrasonography findings are the gold standard for the diagnosis. Spiramycin was used for embryo protection.
Postpartum Congestive Heart Failure Due to Diastolic Dysfunction: Importance of Advan...
Matthew Gottbrecht
Leslie Panella

Matthew Gottbrecht

and 5 more

April 17, 2021
We present a case of a 25 year-old female who developed acute hypoxic respiratory failure secondary to postpartum heart failure with preserved ejection fraction. Despite essentially normal tissue Doppler velocities and E/e’ ratio by existing guidelines for the adult population, available literature suggests that our patient’s markers of diastolic function were significantly abnormal relative to what is expected in the third trimester of pregnancy. Advanced echo-Doppler analysis and her clinical presentation support the presence of underlying diastolic dysfunction. This case illustrates the challenges associated with the diagnosis of diastolic dysfunction during pregnancy and the need for pregnancy specific guidelines.
Worm addendum thickness and gear curvature interference for enveloping cylindrical wo...
Xinyue Zhu
Yaping Zhao

Xinyue Zhu

and 4 more

April 17, 2021
The purpose of this paper is to provide the calculation methods on worm addendum thickness and curvature interference limit line, and find the feasible value range of the technological crossing angle to avoiding addendum sharpening and curvature interference for enveloping cylindrical worm drive with arc-toothed worm. In accordance with the features of the proposed worm, the mathematical models of cutting and working are established. Based on this, the tooth profile geometry of the worm in its axial section and the worm addendum thickness are obtained by geometric analysis and calculation, and then, the feasible value range of the technological crossing angle is given. In virtue of vector rotation and elimination method, the nonlinear equation with one variable for solving the interference limit line is determined. In the process of solving nonlinear equation, the method of geometric construction is used to judge the existence of solutions and provide an initial value for the subsequent iterative calculation. The numerical example results show that with the increases of the technological crossing angle, the interference limit line is close to the boundary line of the conjugate region of the worm pair, and the hazard of curvature interference evident increases. Generally, a smaller value of the technological crossing angle within its available value range can completely avoid the occurrence of the curvature interference.
Evaluation of endothelial dysfunction in COVID-19 with flow-mediated dilatation
Aslı Kurtar Mansıroğlu
Hande SEYMEN

Aslı Kurtar Mansıroğlu

and 3 more

April 17, 2021
Aim: It is a well-known fact that inflammation plays a crucial role in many diseases including COVID-19. Using flow-mediated dilatation (FMD), we aimed to compare the effects of inflammation on endothelial dysfunction in patients with COVID-19 and the control group. Materials and Methods: The present study was conducted on a total of 161 participants, of whom 80 were diagnosed with COVID-19 within the last 6 months (comprising 48 women and 32 men with a mean age of 32.10 ± 5.87 years) and 81 were healthy controls (comprising 45 women and 36 men with a mean age of 30.51 ± 7.33 years). We analyzed the findings of transthoracic echocardiography and FMD in all participants. Results: Except for FMD, there was no statistically significant difference in echocardiographic parameters. (9.52 ± 5.98 vs. 10.53 ± 6.31, p=0.010). In multivariate analysis with the forward stepwise model, FMD was significantly different in the control group compared to the COVID group (1.086 (1.026 - 1.149), p=0.04). Spearman’s correlation test indicated that FMD (r=0.27, p=0.006) had a significantly positive correlation with the presence of COVID. A receiver operating curve analysis revealed that an FMD value of <10.62% was capable of predicting the presence of COVID with a sensitivity and specificity of 64% and 59%, respectively (AUC=0.625, 95% CI, 0.538 - 0.711). Conclusion: The value of FMD decreased significantly in COVID-19 patients compared to the healthy subjects, which may be an early marker for COVID-19 induced endothelial dysfunction. KEYWORDS: COVID-19, endothelial dysfunction, flow-mediated dilatation (FMD
Evaluation of Right Ventricular Function in Patients with Severe and Very Severe Mitr...
Leila Bigdelu
Morteza Boskabady

Leila Bigdelu

and 5 more

April 17, 2021
Background: Right Ventricular (RV) failure has a critical role in the onset and progression of clinical symptoms and the prognosis of patients with Mitral Stenosis (MS), but the exact role, effect, and pathophysiology of RV dysfunction in MS is still controversial. In this study, we aimed to evaluate echocardiographic signs of systolic RV dysfunction using Tissue Doppler Imaging (TDI) and Velocity Vector Imaging (VVI) in subjects with severe and very severe MS. Methods: 46 isolated MS cases (23 severe and 23 very severe) and 23 healthy controls were enrolled in this study. RV function was assessed by tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and peak systolic velocity of the tricuspid annulus (S’) using TDI, and RV free wall strain (RVFWS) employing VVI. Furthermore, these values were compared with mitral valve area (MVA) and pulmonary arterial pressure (PAP). Results: TAPSE, FAC, S’, and RVFWS values were substantially declined in MS cases compared with healthy controls. Moreover, PAP values were considerably increased in MS subjects. Additionally, S’ and TAPSE values were significantly lower in very severe MS patients compared with severe patients. Conclusion: RV systolic function deteriorates in patients with severe and very severe MS. It appears that the degree of the severity of MS can proportionately affect the extent of RV dysfunction and some of its echocardiographic markers such as S’ and TAPSE. TDI and VVI can be used as practical early diagnostic methods for RV dysfunction in MS.
Model-informed precision dosing of levetiracetam in pediatrics population
Julia Macente
Frederico Martins

Julia Macente

and 7 more

April 17, 2021
Aims: Assessing the suitability and safety of doses of levetiracetam in pediatrics using physiologic-based pharmacokinetic (PBPK) modeling. Methods: A PBPK model of levetiracetam was developed and validated for healthy adults and scaled for children (0.5 to 12 years old). Prediction of levetiracetam exposure at steady- state, were carried out for different therapeutic regimens to achieve the target of Cmax values within the therapeutic range of 5 to 46 µg ml-1. Then, a multivariate linear regression analysis (MLR) was applied to correlate the simulated data with covariates: dose, therapeutic regimen, sex, age and body weight (BW), to describe the best model prediction for the initial dosing in pediatrics. Results: The results indicated the suitability of the PBPK model for adults and pediatrics. For children aged 0.5 to 6 y.o. the dose range capable of reaching the pharmacokinetic target is between 10 and 100 mg kg-1 day-1, for 7 to 9 y.o. doses between 20 and 90 mg kg-1 day-1, and for 10 to 12 y.o. doses between 20 to 80 mg kg-1 day-1. Further, the MLR related Cmax to dose, therapeutic regimen, and BW. Conclusions: For 3 daily administrations, it is suggested that maximum daily doses of 80 mg kg-1 could be used for ages between 0.5 and 6 y.o. and 100 mg kg-1 for ages above 7 years old, since they weigh below 50 kg. The PBPK model lumped to MLR could be very supportive for clinical decisions to safety and effectiveness of prescription of levetiracetam along the titration phase.
Four key challenges in the era of big data: Ecology must move beyond Noah's ark
Rob Salguero-Gómez

Rob Salguero-Gómez

and 1 more

April 19, 2021
A document by Rob Salguero-Gómez. Click on the document to view its contents.
Histone acetylation regulates the expression of genes involved in worker reproduction...
Marina Choppin
Barbara Feldmeyer

Marina Choppin

and 2 more

April 29, 2021
In insect societies, the queen monopolizes reproduction while workers perform tasks such as brood care or foraging. Queen loss leads to ovary development and lifespan extension in workers from many ants. However, the underlying molecular mechanisms of this phenotypic plasticity remain unclear. Recent studies highlight the importance of epigenetics in regulating plastic traits in social insects. We investigated the role of histone acetylation in the regulation of worker reproduction in the ant Temnothorax rugatulus. We removed queens from their colonies to induce worker fecundity, and either fed workers with chemical inhibitors of histone acetylation (C646), deacetylation (Trichostatin A), or the solvent (DMSO) as control. We monitored worker number for six weeks after which we assessed ovary development and sequenced fat body mRNA. Workers survived better in queenless colonies and developed their ovaries after queen removal in control colonies as expected, but not in colonies treated with chemical inhibitors. Both inhibitors affected gene expression, although the inhibition of histone acetylation using C646 influenced the expression of more genes with immunity, fecundity, and longevity functionalities. Interestingly, these C646-treated workers shared many upregulated genes with infertile workers from queenright colonies. We also identified one gene with antioxidant properties commonly downregulated in infertile workers from queenright colonies and both C646 and TSA-treated workers from queenless colonies. Our results indicate that histone acetylation is involved in the molecular regulation of worker reproduction and lifespan, and thus point to an important role of histone modifications in modulating phenotypic plasticity of life history traits in social insects.
Peripheral vascular access from the arms for electrophysiology procedures using ultra...
Suraj Kadiwar
Jack Griffiths

Suraj Kadiwar

and 9 more

April 17, 2021
Introduction Vascular access has traditionally been gained from the femoral vessels, however, a ‘radial-first’ approach has become increasingly popular and resulted in lower complication rates and reduced healthcare costs. A “superior” approach has been reported for electrophysiology (EP) studies but is associated with an increased risk. To provide comprehensive anatomical evidence that the vessels of the arms are suitable for use during EP procedures, as assessed by vascular ultrasound. Methods A portable ultrasound device was used to measure the diameter of the brachial artery, brachial, basilic & cephalic veins on the left and right upper limbs of 63 healthy volunteers. A subgroup of 15 volunteers had additional measurements taken with a tourniquet. Results The basilic vein had the largest diameter with a median of 4.6 mm and 4.5 mm (right and left diameter, respectively), followed by the cephalic (median of 3.1 and 3.0 mm) and the brachial vein (median of 2.8 mm). 100% of volunteers had at least one vein that was equal to a 3 mm diameter (which would allow for an 8F sheath), with 98% having 2 suitable veins and >80% having 3 suitable venous vessels. More than 90 % had a suitable diameter for both the right and left brachial artery. There was no correlation between BMI, height, weight, but men had significantly larger basilic veins and brachial arteries (p<0.05). Conclusion We demonstrate the anatomic evidence that the vessels in the arm(s) are capable of housing the size of sheath commonly used in the EP lab.
Effects of Sevelamer Carbonate versus Calcium Acetate on Vascular Calcification, Infl...
Darius Mason
Kavitha Godugu

Darius Mason

and 3 more

April 17, 2021
Rationale & Objective: Hyperphosphatemia is present in most patients with end-stage renal disease (ESRD) and has been associated with increased cardiovascular mortality. Phosphate binders (calcium-based and calcium free) are the mainstay pharmacologic treatment to lower phosphorus levels in patients with ESRD. Study Design: We evaluated biochemical markers of vascular calcification, inflammation, and endothelial dysfunction in patients with Chronic Kidney Disease (CKD) treated with sevelamer carbonate versus calcium acetate. Setting & Participants: We enrolled 50 CKD patients (stages 3 and 4) and treated them with sevelamer carbonate and calcium acetate for 12 weeks. Outcomes: At the end of the study the biomarkers of vascular calcification, inflammation, and endothelial dysfunction were analyzed. Results: A significant increase in HDL-cholesterol was observed with sevelamer carbonate but not with calcium acetate. Treatment with sevelamer carbonate reduced serum phosphate, calcium phosphate, and FGF-23 levels and there was no change with calcium acetate treatment. The inflammatory markers IL-8, IFN-γ, and TNFα decreased with response to both treatments. The levels of IL-6 significantly increased with calcium acetate treatment and no change was observed in the sevelamer carbonate treatment group. Conclusion: Sevelamer carbonate showed favorable effects on anti-inflammatory and vascular calcification biomarkers compared to calcium acetate treatment. Funding: Funding was received from Sanofi/Genzyme. Trial Registration: Registered at trial.com, registration number NCT01277497.
A constraint-based modeling approach to reach an improved chemically defined minimal...
Aidin  Behravan
atieh hashemi

Aidin Behravan

and 2 more

April 17, 2021
Increasing demand for recombinant therapeutic proteins highlights the necessity of their yield improvement. Culture medium formulation is a popular approach for bioprocess optimization to improve therapeutic protein production. Constraint-based modeling can empower high-precision optimization through information on how media compounds affect metabolism and cell growth. In the current study, a genome-scale metabolic model (GEMM) of Escherichia coli cells was employed to design strategies of minimal medium supplementation for higher antiEpEX-scFv production. Dynamic flux balance analysis of the recombinant E. coli cell model predicted that ammonium was depleted during the process. Based on the simulations, three amino acids (Asn, Gln and Arg) were chosen to be added to the medium to compensate for ammonium depletion. Experimental validation suggested that the addition of these amino acids (one-by-one, or in combinations) can indeed improve cell growth and recombinant protein production. Then, design of experiment was used to optimize the concentrations of amino acids in the growth medium. About two-fold increase in the growth rate and total scFv expression level was observed using this strategy. We conclude that the GEMM-based approach can provide insights into an effective feeding strategy to improve the production of recombinant protein in E. coli.
Nitrogen and phosphorus addition differentially enhance seed production of dominant s...
Lei Su
Mengzhou Liu

Lei Su

and 6 more

April 16, 2021
Previous studies have demonstrated changes in plant growth and reproduction in response to nutrient availability, but how investigations of such responses to multiple levels of nutrient enrichment remains unclear. In this study, we manipulated nitrogen (N) and phosphorus (P) availability to examine seed production responses to three levels each of N and P addition in a factorial experiment: no N addition (0 g N m-2 yr-1), low N addition (10 g N m-2 yr-1), high N addition (40 g N m-2 yr-1), and no P addition (0 g P m-2 yr-1), low P addition (5 g P m-2 yr-1), high P addition (10 g P m-2 yr-1). Low N addition enhanced seed production by 814%, 1371%, and 1321% under ambient, low, and high P addition levels, respectively. High N addition increased seed production by 2136%, 3560%, and 3550% under ambient, low, and high P addition levels, respectively. However, P addition did not affect seed production in the absence of N addition, but it did enhance it under N addition. Furthermore, N addition enhanced seed production mainly by increasing the tiller number and inflorescence abundance per plant, whereas P addition stimulated it by decreasing the plant density yet stimulating height of plants and their seed number per inflorescence. Our results indicate seed production is limited not by P but rather by N in the temperate steppe, whereas seed production will be increased by P addition when N availability is improved. These findings enable a better understanding of plant reproduction dynamics of steppe ecosystems under intensified nutrient enrichment and can inform their improved management in the future.
Long Term Disruption of Cytokine Signalling Networks are Evident Following SARS-CoV-2...
Sinead Ahearn Ford
Nonhlanhla Lunjani

Sinead Ahearn Ford

and 17 more

April 16, 2021
Long Term Disruption of Cytokine Signalling Networks are Evident Following SARS-CoV-2 InfectionSinead Ahearn-Ford1, Nonhlanhla Lunjani1, Brian McSharry1,2, John MacSharry1,2,3, Liam Fanning1,3, Gerard Murphy4, Cormac Everard4, Aoife Barry4, Aimee McGreal4, Sultan Mohamed al Lawati4, Susan Lapthorne4, Colin Sherlock4, Anna McKeogh4, Arthur Jackson4, Eamonn Faller4, Mary Horgan3,4, Corinna Sadlier4, Liam O’Mahony1,2,3*1APC Microbiome Ireland, University College Cork, Cork, Ireland2School of Microbiology, University College Cork, Cork, Ireland3Department of Medicine, University College Cork, Cork, Ireland4 Department of Infectious Diseases, Cork University Hospital, Cork, Ireland*Corresponding author – liam.omahony@ucc.ieTo the Editor,The current pandemic caused by the SARS-CoV-2 virus has so far infected more than 130 million people worldwide, resulting in approximately 3 million deaths. While the current clinical and public health priorities are designed to limit severe acute and fatal episodes of the disease, and to quickly roll out vaccines to the general population, it has become apparent that there may also be significant detrimental long-term effects following SARS-CoV-2 infection that impact daily functioning and quality of life1. The mechanisms underpinning the post-acute sequelae of SARS-CoV-2 infection’s long-lasting symptoms can include direct effects of the infection (e.g. endothelial damage, lung fibrosis) or indirect effects associated with changes in the microbiome or abnormalities in inflammatory and immune signalling pathways stimulated by the infection2,3.In order to examine the potential long-term immune changes that occur following elimination of the primary infection, we examined the levels of 52 cytokines and growth factors (using MSD multiplex kits) in the serum of patients that attended follow-up post-COVID infection clinics at Cork University Hospital, Cork, Ireland (The Clinical Research Ethics Committee of the Cork Teaching Hospitals approved this study and all patients provided informed consent). All patients had been hospitalised for PCR-proven SARS-CoV-2 infection (median in-patient stay of 5.5 days, range 1 day to 24 days) during the first wave of the pandemic in Ireland (March-May 2020). 38 serum samples were obtained from 24 patients (median age 53.5 years, 11 female) at 3-9 months following hospital discharge. Clinical severity ranged from mild to critical during hospitalisation and the most common symptoms at follow-up clinics were fatigue and/or dyspnoea (supplementary Table S1). Sera obtained prior to the pandemic from 29 healthy volunteers (median age 43.2 years, 14 female) were analysed in parallel.Of the 52 analytes measured, 19 were significantly elevated in post-COVID patient sera compared to healthy controls (supplementary Table S2). These 19 mediators are illustrated as dot plots in Figure 1 and Figure 2. One group of mediators, c-reactive protein (CRP), serum amyloid A (SAA), Interleukin-1 receptor antagonist (IL-1RA), IL-6, IL-8, IL-15, IL-16, monocyte chemotactic protein (MCP)-1 and MCP-4, can be broadly categorised as being associated with ongoing inflammatory responses (Figure 1a)4. These mediators remained as elevated in samples taken 6-9 months following hospital discharge as those levels observed 3-6 months following discharge (p<0.05 versus controls, ANOVA). A second group of mediators, vascular endothelial growth factor (VEGF-A), soluble tyrosine-protein kinase receptor Tie-2 (Tie-2), soluble intercellular adhesion molecule (ICAM-1) and basic fibroblast growth factor (bFGF), can be generally associated with endothelial dysfunction, remodelling and angiogenesis (Figure 1b)5. The remaining elevated mediators are associated with patterns of lymphocyte polarisation. Elevated IL-4, macrophage-derived chemokine (MDC) and thymic stromal lymphopoietin (TSLP) sera levels indicate activation of TH2 responses (Figure 2a), while IL-17A, macrophage inflammatory protein (MIP)-3α and IL-12/23p40 indicate ongoing TH17 activity (Figure 2b). Other indicators of TH2-associated activities are just outside statistical significance (IL-5, p=0.06; supplementary Table S2). While TH1 responses are well described to be upregulated during acute infection6, the levels of these mediators (e.g. IFN-γ, IP-10) decrease following elimination of the virus and are at control levels in our cohort of post-COVID patients (supplementary Table S2).Our data suggests that there are long term immunological consequences following SARS-CoV-2 infection, at least in those that had acute symptoms severe enough to require hospitalisation. While the relatively low number of patients included in our study at this stage does not allow us to perform subgroup analysis, it is possible that these immune mediators may associate with clinically meaningful disease variables and ultimately may be of therapeutic value, if findings are replicated in future studies. Of particular interest is the elevation in TH2-associated mediators. Could this response be a component of the mucosal repair mechanisms that occur following viral damage, or does this indicate new TH2-associated pathological immune activity that might underpin an increased risk of developing allergy or asthma? Clearly the potential immune mechanisms underpinning the emerging post-COVID clinical entities will become increasingly more important to understand as the health care systems adapt to caring for large numbers of COVID-19 survivors during the coming months and years.
Use of Evidence in Acute Stroke Decision-Making: Implications for Evidence-Based Medi...
Timothé Langlois-Thérien
Brian Dewar

Timothe Langlois-Therien

and 3 more

April 16, 2021
Evidence-Based Medicine proposes a prescriptive model of physician decision-making in which “best evidence” is used to guide best practice. And yet, proponents of EBM acknowledge that EBM fails to offer a systematic theory of physician decision-making. In this paper, we explore how physicians from the neurology and emergency medicine communities have responded to an evolving body of evidence surrounding the acute treatment of patients with ischemic stroke. Through analysis of this case study, we argue that EBM’s vision of evidence-based medical decision-making fails to appreciate a process that we have termed epistemic evaluation. Namely, physicians are required to interpret and apply any knowledge — even what EBM would term “best evidence” — in light of their own knowledge, background and experience. This is consequential for EBM as understanding what physicians do and why they do it would appear to be essential to achieving optimal practice in accordance with best evidence.
Bronchoalveolar Lavage Profiles in Uncontrolled Wheezy Children Compared by Asthma Pr...
Dima Ezmigna
Mark Brown

Dima Ezmigna

and 3 more

April 16, 2021
The Asthma Predictive Index (API) predicts later asthma in preschoolers with frequent wheeze. We hypothesized that airway cytology differs between API positive(+ve)/negative(-ve) children with uncontrolled/recurrent wheezing with dominance of eosinophils in API (+ve) and neutrophils in API (-ve) groups respectively. Objective: To compare bronchoalveolar lavage (BAL) cell profiles in API (+ve)/(-ve) children with recurrent wheezing unresponsive to inhaled corticosteroids (ICS). Design: A retrospective analysis of BAL in 43 children, 3-36 months (median: 14 months) receiving ICS (31 API +ve ; 12 API -ve). BAL cell differential counts, bacterial/viral cultures, and lipid-laden macrophage percentages (LLM) were analyzed. Cell counts presented as median (range). Results: Neutrophil percentages were increased in both groups [API -ve 16% (1-76%); API +ve 42% (1-95%); P=NS]. Cell percentages were similar for lymphocytes [API-ve 12% (1-30%); API +ve 7% (1-37%)], and macrophages [API -ve 67.5% (12-97%); API +ve 41 % (2-94%)]. Eosinophil percentages were low in both groups [API -ve 1 % (1-2%); API +ve 1 % (1-11%)]. Bacterial cultures were positive in 16 (80%) API +ve and 4 (33%) API -ve patients (P=0.10). Conclusion: Cell profiles do not differ between API groups in children ≤36 months with recurrent wheezing unresponsive to ICS. Positive correlation between neutrophil percentages and positive bacterial cultures was seen independent of API. Persistent bacterial bronchitis likely plays an important role in the persistence of symptoms unresponsive to inhaled corticosteroid therapy regardless of API status with a trend to more positive cultures in API positive children.
“Money was the Problem”: Financial Difficulty is the Main Reason for Treatment Abando...
Barnabas Atwiine
Imelda Busingye

Barnabas Atwiine

and 10 more

April 16, 2021
Introduction - Treatment abandonment contributes significantly to poor survival of children with cancer in low-middle-income countries (LMICs). In order to inform an approach to this problem at our Cancer Unit, we investigated why caregivers withdraw their children from treatment. Methods – In a qualitative study, in-depth interviews were conducted with caregivers of children who had abandoned cancer treatment at the Paediatric Cancer Unit (PCU) of Mbarara Regional Referral Hospital (MRRH) in South Western Uganda, between May 2017 and September 2020. Recorded in-depth interviews with caregivers were transcribed and analyzed to identify themes of caregiver self-reported reasons for treatment abandonment. Results - Seventy-seven out of 343 (22.4%) children treated for cancer at MRRH abandoned treatment during the study period; 20 contactable and consenting caregivers participated in the study. The median age of children’s caregivers was 37 years and most (65%) were mothers. At the time of this study, eight (40%) children were alive and 5 (62.5%) were males; with a median age of 6.5 years. Financial difficulties, other obligations, the child falsely appearing cured, preference for alternative treatments, belief that cancer was incurable, fear that the child’s death was imminent and chemotherapy side-effects were the caregivers’ reasons for treatment abandonment. Conclusions and Recommendation – Treatment abandonment among children with cancer in Uganda is, most times, as a result of difficult conditions beyond the caregivers’ control and needs to be approached with empathy and support.
RESUSCITATION AFTER CARDIAC SURGERY AWARENESS, AN EGYPTIAN MULTICENTRE SURVEY
Moslem Abdelghafar
Taher Abdelmoiem

Moslem Abdelghafar

and 3 more

April 16, 2021
Aim: Cardiac surgery patients have different resuscitative needs than other patients who experience in-hospital cardiac arrest, this was addressed in the guidelines. However, it is unknown how widely the guidelines are practiced, or a training protocol is followed in different cardiac surgery units in Egypt. Methods: A 21-question survey is created and included: Participants demographics, Prevalence of cardiac arrest, Cardiac arrest protocol, Emergency resternotomy technique, Training protocols. Survey was disseminated through social media messaging platforms during the period between November 2020 and January 2021. Results: 95 responses were from 11 centres across Egypt. 68.5% of the respondents were surgeons, 76.8% of participants were junior surgeons. For patients who go into VF after cardiac surgery, respondents would attempt a median of 3 shocks with only 24.2% commencing defibrillation shocks before external cardiac massage, while the majority initiating CPR immediately and performing emergency resternotomy in a median time of 10 mins. 56.8% would give 1 mg of adrenaline as soon the cardiac arrest was established. If a surgeon was not available, only 36.8% of respondents would allow any trained personnel to perform the emergency resternotomy. Only 9.5% practice regularly on emergency sternotomies. 75% think tailored training is important and staff should be oriented about it in the future. Conclusion: An action plan is required to improve the awareness of the junior surgeons with the Cardiac Advanced Life Support Protocol.
URINER INCONTINENCE SCREENING INVOLVING 6957 MIDDLE SCHOOL STUDENTS IN THE ESKİSEHİR...
AYFER ACIKGOZ
Mukaddes Baskaya

AYFER ACIKGOZ

and 4 more

April 16, 2021
Aim: Urinary incontinence is an important problem that can arise due to neurogenic or functional reasons and can negatively affect the psychological, social and personality development of children. This study was conducted in Eskişehir province, on secondary school students in order to determine the prevalence and nature of urinary incontinence at night and/or daytime. Methods: The study universe included all secondary school students attending state elementary schools in the city center of Eskişehir (N=34.000). Ethics Committee and Provincial Directorate of National Education approval was obtained before conducting the study, which was supported by Eskişehir Osmangazi University Scientific Research Projects Commission (2017-1876) . A data collection form prepared by the researchers, and a consent form were delivered in sealed envelope to the parents via the students. The study data were collected between 09.05.2018-30.05.2018. Only volunteers were included in the study. 6957 questionnaires which have been fully completed from the 7370 surveys have been taken into consideration. The statistical analysis was carried out using the SPSS soft ware package. Results: The number of children found to have urinary incontinence was determined to be 215 (3.1%). It has been determined that 33 children (0.5%) have urinary incontinence only at daytime, 61 children (0.9%) have urinary incontinence both at night and daytime, and 121 children (1.7%) have urinary incontinence only at night. It was observed that 56% of the children suffering from urinary incontinence had not applied to any health institution for treatment before. Conclusions: Children and families with urinary incontinence need medical information and support to cover the cause of the problem and suggestions for solutions. Accompanying pathologies in cases to be detected can be determined in the early period by means of school screenings and medical evaluation and support can prevent the psychosocial and personality development of children from being adversely affected.
Comparison of Household Income In In-Hospital Outcomes After Implantation of Left Ven...
Bertrand Ebner
Morgan Karetnick

Bertrand Ebner

and 8 more

April 16, 2021
Introduction: Due to the inability to keep up with the demand for heart transplantation, there is an increased utilization of left ventricular assist devices (LVAD). However, paucity of data exists regarding the association of household income with in-hospital outcomes after LVAD implantation. Methods: Retrospective cohort study using the NIS to identify all patients ≥18 years who underwent LVAD implantation from 2011-2017. Statistical analysis was performed comparing low household income (≤50th percentile) and high income (>50th percentile). Results: A total of 25,503 patients underwent LVAD implantation. The low-income group represented 53% and the high-income group corresponded to 47% of the entire cohort. The low-income group was found to be younger (mean age 55 ±14 vs. 58 ±14 years), higher proportion of females (24% vs. 22%), and higher proportion of blacks (32% vs. 16%, p<0.001 for all). The low-income group was found to have higher prevalence of hypertension, chronic pulmonary disease, smoking, dyslipidemia, obesity and pulmonary hypertension (p<0.001 for all). However, the high-income cohort had higher rate of atrial tachyarrhythmias and end-stage renal disease (p<0.001). During hospitalization, patients in the high-income group had increased rates of ischemic stroke, acute kidney injury, acute coronary syndrome, bleeding and need of extracorporeal membrane oxygenation (p<0.001 for all). We found that the unadjusted mortality had an OR 1.30 (CI [1.21-1.41], p<0.001) and adjusted mortality of OR 1.14 (CI [1.05-1.23], p=0.002). Conclusion: In patients undergoing LVAD implantation nationwide, low-income was associated with increased comorbidity burden, younger age, and fewer in-hospital complications and all-cause mortality.
Systematic review and meta-analysis of the effect of ABO blood group on the risk of C...
George Balaouras
Paolo Eusebi

George Balaouras

and 2 more

April 16, 2021
We have been experiencing a global pandemic with baleful consequences for mankind, since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) was first identified in Wuhan of China, in December 2019.  So far, several potential risk factors for SARS-CoV-2 infection have been identified. Among them, the role of ABO blood group polymorphisms has been studied with results that are still unclear. The aim of this study was to collect and meta-analyze available studies on the relationship between SARS-CoV-2 infection and different blood groups, as well as Rhesus state. We performed a systematic search on PubMed/MEDLINE and Scopus databases for published articles and preprints. Twenty-two studies, after the removal of duplicates, met the inclusion criteria for meta-analysis with ten of them also including information on Rhesus factor. The odds ratios (OR) and 95% confidence intervals (CI) were calculated for the extracted data. Random-effects models were used to obtain the overall pooled ORs. Publication bias and sensitivity analysis were also performed. Our results indicate that blood groups A, B and AB have a higher risk for COVID-19 infection compared to blood group O, which appears to have a protective effect. An association between Rhesus state and COVID-19 infection could not be estabished. 
Clinical trials in cardiac xenotransplantation: are we ready to handle ethical issues...
Leonardo Rufino Garcia
Flavio Brito

Leonardo Rufino Garcia

and 7 more

April 16, 2021
Heart allotransplantation has become one of the methods of choice in the treatment of severe heart failure. In the face of its difficulties, such as the unmet balance between organ supply and demand, the use of xenotransplantation might be an attractive option in the near future, even more with the ongoing progress achieved regarding the avoidance of hyperacute rejection and primary organ disfunction, maintenance of xenograft function and control of xenograft growth. To make possible this translational challenge, some points must be taken into account indeed, and they are the equipoise of human benefit and animal suffering, the risk of unknown infections, a well prepared informed consent, ethical and religious beliefs, and the role of cardiac xenotransplantation in a ventricular assistance device era.
Reply to “Additional Data on Protection of the Esophagus during Catheter Ablation of...
Mahmoud Houmsse
Emile Daoud

Mahmoud Houmsse

and 1 more

April 16, 2021
Reply to “Additional Data Protection of the Esophagus During Catheter Ablation of Atrial Fibrillation”Mahmoud Houmsse, MD, and Emile G. Daoud, MDDepartment of Medicine, Division of Cardiology, Richard M. Ross Heart HospitalThe Ohio State University Medical Center, Columbus, OHRunning Title: Protection of EsophagusAddress for correspondence: Emile Daoud, MDDHLRI 473 W. 12th Avenue, Suite 200 Columbus, OH 43210-1252 Telephone: 877-478-2478 FAX : 614-293-5614E-Mail: emile.daoud@osumc.eduFunding: NoneDisclosure: Emile Daoud and The Ohio State University have equity ownership and serve as consultants to S4 Medical Corp, which is manufacturing the Esoultion esophageal retractor.Disclosure: Mahmoud Houmsse has no conflict of interestWe Thank Dr.Clark and Dr. Kulstad for their interest in our recent review manuscript “protection of the esophagus during catheter ablation of atrial fibrillation”We agree with Dr. Clark and Dr. Kulstad that utilization of luminal esophageal temperature (LET) monitoring during atrial fibrillation ablation is inadequate method to avoid esophageal injury. These have been reported in multiple studies that were referenced in our manuscript. The newer published studies regrading monitoring LET during atrial fibrillation ablation, which were reported by Dr. Clark and Dr. Kulstad, have been published during our manuscript publication process. Nevertheless, these studies that reported by Dr. Clark and Dr. Kulstad showed same conclusion of inadequate LET monitoring in preventing esophageal injury 1-3.Regarding active cooling, Dr. Clark and Dr. Kulstad reported recent published studies. First study small pilot study that showed active cooling is much more protective than manual liquid instillation4. The second pilot RCT that compared LET and active cooling showed same outcome like the IMPACT study that we reported in our manuscript 5,6.We agree with Dr. Clark and Kulstad, growing interest in the area of esophageal protection during atrial fibrillation ablation.We do believe, as we stated in the conclusion of our manuscript, that “a reliable method to protect the esophagus is of clinical value, but the ancillary value of reducing physician concern during AF ablation, reducing interruption to ablation work flow, perhaps enhancing AF ablation results and simplifying post procedure management of patient symptoms are also of high importance. Considering the ease of use, minimal side effects, and low costs associated with esophageal protection devices, these features offer compelling evidence for use of esophageal protection as routine care for AF ablation”.
Structural and allergenic properties of the Fatty Acid Binding Protein from shrimp Li...
Marlon Munera
Dalgys Martinez

Marlon Munera

and 6 more

April 16, 2021
Background: The shrimp Litopaneus vanammei is an important source of food allergens but its allergenic repertoire is poorly characterized. Cross reactivity between crustacean and mites has been characterized, with tropomyosin, the most relevant allergen involved. The aim of this study was the structural and immunological characterization of an allergen belonging to the Fatty Acid Binding Protein (FABP) family from L. vannamei (LvFABP). Methods: ELISA, skin prick test (SPT) and basophil activation assays were performed to determine IgE reactivity and allergenicity of LvFABP. LC-MS/MS and Circular Dichroism experiments were done for structural analysis. B-cell epitope mapping with overlapping peptides, and cross-inhibition studies using human sera were done to identify antigenic regions and cross-reactivity. Results: The recombinant LvFABP showed IgE reactivity in 27% of allergic patients tested and showed allergenic activity when tested for basophil activation and SPT in shrimp sensitized patients. CD-spectroscopy of LvFABP revealed that the protein is folded with a secondary structure composed of mainly β-strands and a smaller fraction of  helices. This is consistent with molecular modelling results, which exhibit a typical β barrel fold with two α-helices and ten β-strands. Epitope mapping identified two IgE binding antigenic regions and inhibition assays found high cross reactivity between LvFABP and Blo t 13, mediated by the antigenic region involving amino acids 53 to 73. Conclusions: Our results support LvFABP as an allergen with cross reactivity with the allergen Blo t 13. This new allergen could help to understand new mechanisms of sensitization to seafood such as shrimp.
Nutrients and herbivores impact grassland stability across multiple spatial scales th...
Q. Q. Chen
Shaopeng Wang

Q. Q. Chen

and 21 more

April 16, 2021
Nutrients and herbivores have independent effects on the temporal stability of aboveground biomass in grasslands; however, their joint effects may not be additive and may also depend on spatial scales. In an experiment adding nutrients and excluding herbivores in 34 globally distributed grasslands, we found that nutrients and herbivores mainly had additive effects. Nutrient addition consistently reduced stability at the local and larger spatial scales (aggregated local communities), while herbivore exclusion weakly reduced stability at these scales. Moreover, nutrient addition reduced stability primarily by causing changes in local community composition over time and by reducing local species richness and evenness. In contrast, herbivore exclusion weakly reduced stability at the larger scale mainly by decreasing asynchronous dynamics among local communities, but also by weakly decreasing local species richness. Our findings indicate disentangling the influences of processes operating at different spatial scales may improve conservation and management in stabilizing grassland biomass.
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