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Impact of Intraoperative Norepinephrine Support on Pediatric Living Donor Liver Trans...
Yu-Gang Lu
Jiang-Long Chen

Yu-Gang Lu

and 6 more

April 14, 2020
Aim Norepinephrine (NE) is often administered during the perioperative period of liver transplantation. However, its role and safety profile have yet to be evaluated in pediatric living donor liver transplantation (LDLT). The aims of this study was to analyze the effect of intraoperative NE infusion on recipients’ survival following pediatric LDLT. Methods A retrospective study of 430 pediatric patients receiving LDLT between 2014 and 2016 at Renji Hospital was conducted. We evaluated patient survival among recipients who received intraoperative NE infusion (NE group, 85 recipients) and those that did not (Non-NE group, 345 recipients). Results The number of children aged over 24 months and weighing more than 10 kg in NE group was more than that in Non-NE group. And children in NE group had longer operative time, longer anhepatic phase time and more fluid infusion. After multivariate regression analysis and propensity score regression adjusting for confounding factors to determine the influence of intraoperative NE infusion on patient survival, the NE group had a 169% more probability of dying. Although there was no difference in mean arterial pressure changes relative to the baseline between the two groups, we did observe increased heart rates in NE group compared with those of the Non-NE group at anhepatic phase (P=0.025), neohepatic phase (P=0.012) and operation end phase (P=0.017) of the operation. Conclusion Intraoperative NE infusion was associated with poor prognosis for pediatric LDLT recipients. We recommend the application of NE during pediatric LDLT should be indicated carefully to avoid potentially hazardous effects.
Diastolic Function of the Left and Right Ventricles of the Heart in Outpatients with...
Venera Kirillova
Alla Garganeeva

Venera Kirillova

and 2 more

April 14, 2020
The aim of the study is to investigate the impairment of diastolic function of the left ventricle (LV) and the right ventricle (RV) in arterial hypertension outpatients. Materials and methods. Arterial hypertension patients (n=299) and practically healthy people (n=62) were examined on an outpatient basis. Echocardiographically, diastolic dysfunctions of both ventricles were evaluated. Results. All the arterial hypertension patients had a pattern of diastolic dysfunction (DD) of the RV of different grades (grade I RVDD and grade II RVDD), regardless of the presence or absence of pulmonary arterial hypertension. Patterns of grade I LVDD and grade I RVDD were detected in 84 patients. Patterns of grade I LVDD and grade II RVDD were detected in 77 patients. Patterns of grade II LVDD and grade II RVDD were detected in 41 patients. A pattern of grade II RVDD with normal left ventricular diastolic function was detected in 97 patients with a short duration of disease (3.92±0.48 years) versus the other groups with more than 15 years of hypertension. 175 arterial hypertension patients had grade I or II LVDD only in 18.3% of cases according to the recommendations of the American and European societies of echocardiographers (2016). Conclusion. The patients with a short period of hypertensive disease have only the pseudonormal pattern of RVDD, which can be an early diagnostic marker of heart failure. Echocardiographic diagnosis of diastolic function made according to various criteria can both increase the number of chronic heart failure patients and significantly decrease it.
Functional significance of intra-left ventricular vortices on energy efficiency in no...
Miwa Sarashina
Hiroyuki Iwano

Miwa Sarashina

and 12 more

April 14, 2020
Purpose: To investigate the influence of changes in intra left ventricular (LV) vortices on LV energy efficiency (EE) in normal and diseased hearts. Methods: Vector flow mapping echocardiography was performed in 36 normal subjects (N), 36 patients with dilated cardiomyopathy (D), and 36 patients with LV hypertrophy (H). The circulation of main anterior vortex was measured as a parameter of vortex strength and EE was calculated as energy loss divided by LV stroke work. Results: Circulation increased in the order of N, H, and D (N: 15±4, D: 19±8, H: 17±6 10-3m2/s; analysis of variance [ANOVA], P<0.01). Conversely, EE increased in the order of N, D, and H (N: 0.22±0.07, D: 0.26±0.16, H: 0.30±0.16 10-5J/mmHg·mL·m·s; ANOVA, P=0.04), suggesting worst EE in group H. We found a positive correlation between circulation and stroke work only in group N and positive correlation between circulation and EE only in diseased groups (D: R=0.55, P<0.01; H: R=0.44, P<0.01). Multivariable analyses revealed that circulation was the independent determinant of EE in both of groups D and H. Conclusions: Enhanced vortices could work effectively to increase LV external work without loss of EE in normal hearts, while in failing hearts only to worse EE, regardless of the LV morphology.
Audit of lower segment caesarean section at New Mowasat hospital in Kuwait: “Cross -s...
AMINA ELASY
sangeeta dhawan

AMINA ELASY

and 2 more

April 14, 2020
Background Auditing the CS according to a standard criterion will lead to avoid many complications. Clinical audit is a tool to improve quality of care and to reduce maternal and perinatal morbidity and mortality. Objective: to evaluate the current practice and audit against international standards for various parameters relating to elective lower segment caesarean section and to assess compliance of physicians to audit standards. Design: A cross-sectional study. Setting: New Mowasat Hospital in Kuwait from 1st October 2018 until 1st October 2019. Sample: Three hundred and twenty six (326) cases of elective caesarean sections. Methods: The hospital medical, electronic records and case notes were reviewed for study participants. Those women were booked under the care of internal and external physicians. Demographic data and primary outcomes were collected. Outcome: measuring the compliance to the recognized Caesarean Section international standards: consent form, grade of LSCS, antacid and anti-emetics, type of anesthesia, uses of antibiotics, umbilical cord blood PH, and thrombopropylaxis. Results: compliance for a signed consent form (100%) ,cord blood PH(100%),use of preoperative antacid and antiemetic (99.4%) , combined regional anesthesia(53.4%), second generation cephalosporin(61.3%) , thrombopophylaxis ( 78.5 %)of which (33.6%) completed a 10 days duration . There was a statistically significant difference between internal and external physicians compliance regarding, type of anesthesia 2.3 (95%CI, 1.3-4.1p=0.004), type and timing of antibiotics 0.42(95%CI 0.22-0.79, p=0.007) and 0.33 (95%CI 0.172-0.63, p=0.0006) and thrombopophylaxis 8.1 (95%CI 2.80-23.23, p=0.000). Conclusion: the results are encouraging, but suboptimal compliance was noticed mainly among external physicians. Funding: None
Acute brainstem encephalitis associated with Mycoplasma pneumoniae in an adult
Jung-won Shin
Min-Hee Woo

Jung-won Shin

and 1 more

April 14, 2020
Brainstem encephalitis (BE) associated with Mycoplasma pneumoniae in adults is rare and the diagnosis is challenging. We diagnosed BE associated with M. pneumoniae through increasing IgM level using EIA with clinical feature. This method of clinical diagnosis would be helpful to treat with macrolide antibiotics earlier and showed good outcomes.
On The Theoretical and Mathematical Analysis of Hydrodynamics Boundary Layer Fluid Fl...
Ammar Fathi
Ala'a Mahdi

Ammar Fathi

and 2 more

April 14, 2020
References 1. Schlichting, H. and K. Gersten, Boundary-layer theory . 2016: Springer.2. YUNUS, A.C. and J.M. CIMBALA, Fluid Mechanics Fundamentals and Applications. New York, NY–USA: ed . 2006, Mc Graw Hill–Higher Education.3. Reynolds, O., Iv. on the dynamical theory of incompressible viscous fluids and the determination of the criterion. Philosophical transactions of the royal society of london.(a.), 1895(186): p. 123-164.4. Massey, B. and J. Ward-Smith, Mechanics of fluids 8th ed . 2005, Taylor & Francis e-Library.5. Versteeg, H.K. and W. Malalasekera, An introduction to computational fluid dynamics: the finite volume method . 2007: Pearson education.6. Munson, B.R., et al., Fundamentals of Fluid Mechanics, John Wiley & Sons. Inc., USA, 2006.7. Abdulsada, M., Flashback and blowoff characteristics of gas turbine swirl combustor . 2011, Cardiff University.8. Prasad, R. and K. Sreenivasan, The measurement and interpretation of fractal dimensions of the scalar interface in turbulent flows. Physics of Fluids A: Fluid Dynamics, 1990.2 (5): p. 792-807.9. Syred, N., et al. Experimental investigation of the Effect of Air Diffusive injection on premixing swirl flames . in 55th AIAA Aerospace Sciences Meeting . 2017.10. PJ, P., Fox and McDonald’s Introduction to Fluid Mechanics. Hoboken . 2011, NJ: John Wiley & Sons, Inc.11. Houghton, E., et al., Aerodynamics for Engineering Students, 6th Hrsg . 2013, Oxford: Elsevier.
Population pharmacokinetics of gabapentin in patients with neuropathic pain: the role...
Ana Carolina Costa
Jhohann Richard Benzi

Ana Carolina Costa

and 7 more

April 14, 2020
Aims: Gabapentin (GBP) is an α2-δ ligand drug widely used to treat neuropathic pain, especially diabetic neuropathy. The drug presents a saturable absorption in therapeutic doses and it is mainly eliminated unchanged in the urine. GBP excretion has been suggested to be dependent on glomerular filtration rate and active transport by renal drug carriers. Our objective was to evaluate the role of diabetes and glycaemic control on GBP pharmacokinetics using a population pharmacokinetic modelling approach. Methods: A clinical trial was conducted in participants with neuropathic pain of intensity ≥ 4 evaluated by visual analogue scale (VAS) (n=29), due to lumbar or cervical disc herniation or due to diabetic neuropathy. All participants were treated with a single oral dose of 300 mg GBP. Blood samples were collected up to 24 hours after GBP administration. A population pharmacokinetic analysis was conducted to evaluate the inter-individual variability considering as potential covariates weight, height, body mass index (BMI), sex, biomarkers of renal function and diabetes, and genotypes for the main genetic polymorphisms of SLC22A2 and SLC22A4, the genes encoding the transporters for organic cations OCT2 and OCTN1. Results: Population estimates for lag time, first-order absorption rate, total clearance and apparent volume of distribution at steady state were 0.32 h, 1.13 h-1, 14.7 L/h and 140 L, respectively. The total plasma clearance of GBP is affected by the estimated glomerular filtration rate and the volume of distribution increases with higher glycaemic levels. Conclusion: GBP population pharmacokinetics was affected by renal function and glycaemic control.
Understanding Health Care Providers Experiences toward Discussing Costs in the Clinic...
Huthaifah Khrais
Ibrahim Khrais

Huthaifah Khrais

and 1 more

April 14, 2020
Background: Health care providers spend most of their time with patients talking about their physical and emotional status, yet the cost issues is minimally discussed. Objectives: We sought to describe Jordanian nurses and physicians experiences toward cost communication and explore potential predictors for healthcare providers’ experiences toward cost communication. Design: Descriptive correlational survey design. A 15-item questionnaire was used to measure healthcare providers’ experiences regarding the cost communication with patients, focusing on out-of-pocket costs. After piloting, a total of 122 Jordanian nurse and physician (N = 122) were participated in this study. Basic descriptive and inferential statistics were applied. Results: Jordanian health care providers have demonstrating a positive attitude toward communicating cost issues with their patients. Most, about 68%, preferred to explain the cost that patients have to pay. Also, the years of experiences significantly predicted health care provider’s attitude in cost discussion (β = 0.214, p<0.05) Conclusion: Findings support the importance of discussing cost-related issues with patients. Jordanian healthcare providers comfort with and desire to discuss treatment-associated costs; however, some of them lack for quality resources that could help them in cost discussions.
Splice-disrupt genomic variants in prostate cancer: Association of some splice-disrup...
Esmaeil Ebrahimie
Manijeh Manijeh Mohammadi-Dehcheshmeh

Esmaeil Ebrahimie

and 1 more

April 14, 2020
Precise pre-mRNA splicing is vital for appropriate protein translation where splice-disrupt variants may change the structure of transcripts and their encoded proteins, resulting in a complete loss of function or acquiring a new function. Splice-disrupt genomic variants are one of the causes of cancer-causing errors in gene expression. Little is known about splice-disrupt genomic variants. Here, pattern of splice-disrupt variants in different types of prostate cancer was investigated using huge deposited genomic variants in prostate cancer (21,842,764 variants). HLA-A, MSR1, and EGFR had the highest allele frequency of splice-disrupt variation in prostate cancer, castration-resistant prostate cancer, familial prostate cancer, and metastatic castration-resistant, respectively. Intron, followed by CDs and 3’UTR were enriched with the splice-disrupt mutations. Some splice-disrupt variants, on CDs of NCOR2, PTPRC, and CRP that were solely present in advanced metastatic castration-resistant prostate cancer. Damaging splice-disrupt variants were identified based on PolyPhen, SIFT, and GERP++ scores as well as clinical significance. Functional annotation of damaging splice-disrupt variants highlighted important cancer-associated functions including endocrine resistance, lipid metabolic process, steroid metabolic process, regulation of mitotic cell cycle, and regulation of metabolic process. This is the first study that profiles the splice-disrupt genomic variants and their target genes in prostate cancer.
Hemophagocytic lymphohistiocytosis in a patient with worsening weakness
Edward Nabrinsky
Ronald Sirota

Edward Nabrinsky

and 2 more

April 14, 2020
Hemophagocytic lymphohistiocytosis is an under-recognized clinical entity that can present in adults. It is important to consider in the differential diagnosis of patients presenting with non-specific multi-organ dysfunction and inflammation.
Left ventricular cavity obliteration: mechanism of the intracavitary gradient and dif...
Charles Pollick

Charles Pollick

April 14, 2020
Controversy surrounds the cause of the pressure gradient in patients with hypertrophic obstructive cardiomyopathy (HOCM). Left ventricular cavity obliteration (LVCO) was first described as the cause of the gradient but subsequently systolic anterior motion (SAM) of the mitral valve has been established as the cause. Nevertheless, the two gradients, though different in origin and significance, share similar characteristics. They both have a similar “dagger” profile, are obtained from the cardiac apex, are associated with a hyperdynamic left ventricle, and the gradients are worsened by Valsalva. The distinction has clinical relevance, because treating the intra cavitary gradient (ICG) of LVCO as if it were a SAM associated gradient associated with HOCM would be inappropriate and possibly harmful.    To clarify the cause and characteristics of the ICG in patients with LVCO in patients without HOCM we assessed the extent and duration of cavity obliteration and for differentiation we compared the spectral profiles with patients with HOCM and severe aortic stenosis (AS). Higher ICG is associated with greater extent and more prolonged apposition of LV walls. The spectral profile of patients with AS, HOCM and LVCO are differentiated by the peak/mean gradient ratios of 2 or less, 2-3, and 3 or greater, respectively in > 90% of patients. Most patients with LVCO without HOCM or severe LVH have an ICG < 36 mmHg. The magnitude of ICG is quantitatively associated with extent and duration of LVCO. Spectral profiles of severe AS, HOCM, and LVCO can be differentiated by the peak/mean gradient ratio.
Asymptomatic Chronic Traumatic Aortic Valve Perforation with Severe Aortic Regurgitat...
Neeta Bachani
avishek bagchi

Neeta Bachani

and 7 more

April 14, 2020
Here we present a young asymptomatic male incidentally diagnosed to have aortic regurgitation (AR). The patient had a history of a blunt trauma to the thorax two years back but did never have any symptoms. Transthoracic echocardiography showed a moderately dilated left ventricle with normal systolic function and severe AR with normal nondilated aortic root and tri-leaflet aortic valve. To diagnose the etiology of the AR a trans-esophageal echocardiogram (TEE) was done, which revealed a perforation in the non-adjacent leaflet (NAL) and confirmed severe AR with two AR jets being clearly visualised, one through the point of incomplete coaptation and other one through the perforated area in the NAL. The patient was treated with aortic valve replacement and was doing well on follow-up.
Processi per il controllo delle emissioni industriali: verso i metodi biologici
Carmen Granato

Carmen Granato

May 08, 2020
Come risultato della crescente consapevolezza sociale e sviluppo della legislazione, affrontare il problema legato al fastidio degli odori dovuti alle emissioni di composti organici volatili (COV) provenienti da una vasta gamma di impianti industriali, diventa spesso obbligatorio. Per il controllo delle suddette emissioni e per la rimozione, sono disponibili diverse soluzioni che si basano su processi chimico/fisici (assorbimento o lavaggio) che hanno bisogno a loro volta di ulteriori trattamenti oppure su processi biologici e processi avanzati di ossidazione (AOP) che presentano soluzioni più efficaci. Nella prima parte dello studio sono stati confrontati tra loro i principali processi per il trattamento delle emissioni odorigene, attraverso un modello di confronto a coppie prendendo in considerazione  efficacia, prestazioni di processo, possibilità di recupero e impatti ambientali .  Negli ultimi decenni si è assistito a un significativo aumento dell'interesse per i processi di trattamenti biologici quali biofiltri e biotrickling filter in quanto più sostenibili dei convenzionali processi chimico/fisici. Questi ultimi, sono stati anch'essi esaminati attraverso un modello di confronto a coppie, associando, inoltre, un approccio per la selezione del processo in maniera preventiva, per mezzo di un algoritmo semplice basato su un modello ad albero decisionale. I risultati rilevano che la filtrazione biotrickling è il metodo più efficace per la rimozione dei COV idrofili, mentre i biofiltri consentono una rimozione più efficace per i COV idrofobici . Questo articolo può essere utile quando si seleziona, in maniera preliminare e basandosi solo su dati input, una procedura di trattamento per i composti odorosi rispetto ad un’altra.
De novo sequencing and chromosomal-scale genome assembly of leopard coral grouper, Pl...
QIAN ZHOU
Xinyu Guo

QIAN ZHOU

and 11 more

April 14, 2020
The leopard coral grouper, Plectropomus leopardus, belonging to genus Plectropomus, family Epinephelinae, is a carnivorous coral reef fish widely distributing in the tropical and subtropical water of Indo-Pacific Oceans. Due to its appealing body appearance and delicious taste, P. leopardus has become a popular commercial fish for aquaculture in many countries. However, the lack of genomic and molecular resources for P. leopardus hinders its biological studies and genomic breeding programs. Here we report the de novo sequencing and assembly of P. leopardus genome using 10× Genomics and high-throughput chromosome conformation capture (Hi-C) technologies. Using 127.36 Gb 10× Genomics we generated a 902.90 Mb genome assembly with a contig and scaffold N50 of 31.8 Kb and 33.47 Mb, respectively. The scaffolds were clustered and oriented into 24 pseudo-chromosomes with 13.39 Gb valid Hi-C data. BUSCO analysis showed that 95.3% of the conserved single-copy genes were retrieved, indicating a good entirety of the assembly. We predicted 23,234 protein-coding genes, among which 96.5% were functional annotated. The P. leopardus genome provides a valuable genomic resource for genetics, evolutionary and biological studies of this species. Particularly, it is expected to benefit the development of genomic breeding programs in the farming industry.
Association of maternal pre-pregnancy body mass index with adverse pregnancy outcomes...
Jie Tang
Xinhong Zhu

Jie Tang

and 7 more

April 14, 2020
Objective To clarify the association of pre-pregnancy body mass index (BMI) with adverse pregnancy outcomes according to maternal age in a large and diverse population in China. Design Retrospective cohort study. Setting Guangdong Province, China. Population 669101 women participated in the National Free Preconception Health Examination Project in Guangdong Province, China, from 2013 to 2017. Methods BMI were calculated and classified into four categories according to Chinese criteria: underweight (BMI <18.5kg/m2), normal weight (18.5-23.9kg/m2), overweight (24.0-27.9kg/m2), and obesity (≥28.0kg/m2). Main outcome measures Outcomes were preterm birth (PTB), large for gestational age (LGA), small for gestational age (SGA), primary caesarean delivery, shoulder dystocia or birth injury, and stillbirth. Log-binomial models were employed to estimate the adjusted risk ratios (RRs) and 95% confidential intervals (95%CIs) for underweight, overweight and obesity. Results The incidence ratios PTB, LGA, SGA, primary caesarean delivery, shoulder dystocia or birth injury and stillbirth were 5.0%, 11.2%, 9.7%, 14.5%, 1.1% and 1.2‰, respectively. Overall, compared with normal BMI, underweight was associated with increased risk of PTB (adjusted RR 1.06, 95%CI 1.04-1.09) and SGA (1.23, 1.22-1.26); overweight was associated with the increased risk of LGA (1.17, 1.14-1.19), primary caesarean delivery (1.18, 1.16-1.20) and stillbirths (1.44, 1.03-2.06); and obesity was associated with increased risk of PTB (1.12, 1.05-1.20), LGA (1.32, 1.27-1.37), primary caesarean delivery (1.45, 1.40-1.50). These associations were different according to maternal age. Conclusion Maternal pre-pregnancy abnormal BMI were associated with the risks of adverse pregnancy outcomes among Chinese population, but the risks differed according to maternal age.
Volleyball-related Adult Maxillofacial Trauma Injuries: A NEISS Database Study
Jeremy Reich
Jason Cohn

Jeremy Reich

and 5 more

April 14, 2020
Objectives: To describe volleyball-associated craniofacial injuries presenting to emergency departments (EDs) in the United States by patient demographics, injury type, anatomical location, and disposition. Design: An analysis of volleyball-related trauma was conducted using the National Electronic Injury Surveillance System (NEISS). Chi-squared testing (X2) was performed to compare categorical variables. Setting: The NEISS database collects information from approximately 100 EDs under the United States Consumer Product Safety Commission and provides data extrapolated to a nationally representative sample. Participants: The database was queried from years 2009-2018. Main outcome measures: Volleyball-related craniofacial injuries categorized by demographics (age, sex, and race), medical injury information (injury type and location), and patient disposition (observed and discharged, admitted, deceased). Results: A total of 235 volleyball-related facial traumas were recorded with an estimated 10,424 visits occurring nationally. The majority of injuries were among young adults aged 20-29 (52.3%) and was evenly distributed for men and women. Lacerations were the most frequent injury type (37.9%), while the face was the most common site of injury (41.7%). The majority of fractures involved the nose (71.4%) and amongst individuals aged 20 through 49 (90.5%). Males had significantly more lacerations than females (75.3% vs. 24.7%), whereas females had significantly more contusions/abrasions (64.5% vs. 35.5%) and concussions (72.9% vs. 27.1%). Conclusions: Volleyball-related craniofacial injuries can vary depending on patient demographics. This information can help with the development of safety and preventative measures for individuals participating in the sport.
To be decoded. (Mini-commentary on BJOG-19-1802.R1 & BJOG-19-1803.R1)
Zarko Alfirevic
Simon Gates

Zarko Alfirevic

and 1 more

April 14, 2020
Mini-commentary on BJOG-19-1802.R1 & BJOG-19-1803.R1Title: To be decodedZarko Alfirevic,Department of Women’s and Children’s Health, University of LiverpoolSimon GatesCancer Research UK Clinical Trials Unit, University of BirminghamEmail contact: Zarko Alfirevic, Zarko@liverpool.ac.ukRandomised trials remain gold standard for evaluation of effectiveness of medical interventions. However, they are expensive, time consuming and demand huge efforts from participants, researchers and clinical services that facilitate them. Even when trials are successfully completed, peer reviewers often find them wanting. One of the most common criticisms is a ‘lack of power’ to tackle clinically important outcomes. Why is this happening time and again?When an important clinical question creates an equipoise, trialists are faced with difficult choices. If they design a trial to tackle the most important (often rare) outcomes aiming to detect modest, but plausible, risk reductions from a proposed intervention, such studies are rarely feasible and very expensive forcing most funders to simply walk away. Common ‘remedies’ are to change the outcome to something more common and less important (often composite), or to propose an unrealistic risk reduction, sometimes in excess of 50%. Trials of magnesium sulphate for neuroprotection included in the seminal Cochrane review (Doyle LW et al. DOI: 10.1002/14651858.CD004661.pub3) that triggered changes in numerous guidelines world-wide were not an exception (Table 1).Cerebral palsy is a rare, but devastating complication of prematurity and even a very modest reduction would, surely, be worth detecting. The problem is that even in the most ‘at risk’ groups, the incidence of cerebral palsy will not exceed 10%. A conventional sample size calculation estimates that to detect a ‘massive’ 25% risk reduction in cerebral palsy, in excess of 5,000 women would have to be randomised.Interestingly, such a priori sample size calculations are not a feature of most published meta-analyses. Step forward Trial Sequential Analysis (TSA). The TSA is a deceptively simple concept; meta-analysis sample size needs to be increased to allow not only for the heterogeneity of included studies, but also for repeated testing when meta-analyses are being updated and therefore subjected to repeated significance testing. Interested readers can find out more from the Copenhagen Trial Unit’s website - vocal proponents of this methodology (www.ctu.dk/tsa).In their two sister papers, Wolf et al have, quite ingeniously, used TSA to determine the size of their randomised trial and, by doing so, avoided the risk of their randomised trial and updated meta analysis being criticised as ‘underpowered’ (Wolf H et al. BJOG 2020 xxxx (RCT); Wolf H et al. (BJOG 2020 xxxx (SR & MA). Could this concept be a methodological ‘game changer’ in perinatal trials?The concept of TSA has been widely criticised, and a Cochrane Collaboration expert panel recommended against its use (https://methods.cochrane.org/sites/default/files/public/uploads/tsa_expert_panel_guidance_and_recommendation_final.pdf). Key criticisms are, first, that decision-makers require a summary of the currently available evidence and this should not depend on past and future updates. Second, TSA focuses only on statistical significance. Interpretation of meta-analysis should be based on the estimates of the treatment effect and its uncertainty, rather than whether an arbitrary significance threshold is passed. Third, the ways that evidence accumulates in systematic reviews and individual trials are fundamentally different. Review updates are not equivalent to trial interim analyses; updates are not pre-planned and their number cannot be determined in advance. Furthermore, reviews address multiple clinically-relevant effects on several outcomes or subgroup analyses, which need to be integrated into an overall conclusion. The Cochrane expert panel concluded: “Any sequential adjustment procedure is necessarily based on a particular instance of the evolution of evidence that applies to a limited context and cannot satisfy the requirements of all decision makers.”Table 1. Key features of randomised trials of MgSO4given to pregnant women for prevention of cerebral palsy in infants born preterm
Biomass and Pigment Production for Arthrospira platensis via Semi-Continuous Cultivat...
Ankush Karemore
Yanhui Yuan

Ankush Karemore

and 3 more

April 14, 2020
Abstract This study describes the response of Arthrospira platensis to a variety of temperature conditions as reflected in variations of photosynthetic parameters, pigmentation, and biomass productivity in indoor photobioreactor (PBR) cultivations. These experiments are designed to better understand the impact of temperature, seasonal variations, and acclimation effects on outdoor biomass production. The irradiance level and temperature range (20 – 39°C) are chosen to enable modeling of semi-continuous operation of large-scale outdoor PBR deployments. Overall, the cultivations were quite stable with some pigment-related instabilities after prolonged high temperature exposure. Changes in productivity with temperature, as reflected in measured photosynthetic parameters, are immediate and mainly attributable to the temperature dependence of the photosaturation parameter, a secondary factor being variation in pigment content on a longer time scale corresponding to turnover of the culture population. Though pigment changes have minimum impact on productivity, prolonged exposure at 35°C and above yields a clear degradation in performance. Productivities in a semi-continuous operation are quantitatively reproduced with a productivity model incorporating photosynthetic parameters measured herein. This study confirms the importance of temperature for biomass and pigment production in Arthrospira cultivations and provides a basis for risk assessments related to temperature mitigation for large-scale outdoor cultivations. Keywords: Arthrospira Platensis, photosynthetic parameters, pigment production, productivity modeling, photobioreactors
Authors’ reply re: Antenatal magnesium sulphate for the prevention of cerebral palsy...
Hanne Wolf
Jesper Brok

Hanne Wolf

and 10 more

April 14, 2020
Letter to the Editor, BJOG Exchange
COVID19 pandemic, are there reasons to worry about the efficacy of the perinatal care...
Anna Kajdy
Andrzej Torbe

Anna Kajdy

and 4 more

April 14, 2020
The COVID19 outbreak has affected many aspects of people’s lives, including those of pregnant women. Apart from social-distancing, prohibition of assemblies, isolation, quarantine and many other imposed measures, there are restrictions on access to planned medical consultations, diagnostic procedures and interventions. These restrictions may both, directly and indirectly, disturb the stability of healthcare systems.The previous commentaries presented in this journal have discussed the novel virus and the readiness of obstetricians for dealing with COVID 19 positive mothers. [1][2] But what about the rest? What about those without symptoms, that in some countries are home on lockdown? Are we ready to take our pregnant women completely “online”? Do they all qualify? Is it safe? Is it efficient? Is it ethical? What if something goes wrong? Are there laws protecting both sides: the patient and the medical professional?Pregnant women are a specific group of patients. The majority of them are young women without co-morbidities. But pregnancy is a time of increased medical supervision aimed at achieving the best perinatal outcome, reduction of both maternal and neonatal morbidity and mortality.  Pregnancy is a risk factor of COVID-19 infection,  especially in the 3rd trimester [3]. Adequate antenatal care according to both national and international standards may be affected by several factors: healthcare providers limiting consultations to those classified as urgent both in outpatient and inpatient facilities, limited access to medical facilities due to restrictions of travel and transport. All these restrictions have been imposed in good faith as a measure of social distancing. But it has to be noted that as a result, women may be reluctant to visit medical facilities because of fear of contracting the virus, therefore voluntarily waiving their right to access antenatal visits.Statements have been published regarding the use of personal protective equipment (PPE) aimed at minimizing the risk of exposition of medical personnel. As reality shows, access to PPE is limited even in the most efficient health systems [4]. This may also be a burden in the provision of optimal antenatal care in some settings.COVID-19 pandemic has reached more than 200 countries [5]. The mortality rate varies and depends mainly on age and comorbidities. The highest is recorded in countries such as Italy and Spain [5]. The average reported by WHO is 3.4%. Recent reports indicate a significantly lower mortality of 0.66% [6] because previous registries have not included asymptomatic patients.Adequate antenatal care is a standardized medical process aimed at achieving perinatal results characterized by a low percentage of prematurity, low maternal and fetal mortality and morbidity. The preventive measures implemented over the years helped prevent in many cases, serious complications. In recent years, our country Poland has achieved the lowest maternal mortality in the entire European region and one of the lowest perinatal mortality rates.These results can be attributed to doctor or midwife assisted antenatal visits every 3-4 weeks and recommended 3-4 ultrasound examinations in each pregnancy. This system was built on experience, research and organization of a national perinatal care system. We fear that the failure of the system to perform adequately in the light of the imposed restrictions may, in a short time, lead to a deterioration of perinatal results. This the least will be caused by COVID-19 infections in pregnancy. According to previous reports, the course of coronavirus infection is not worse than in the non-pregnant population of the same age [7]. Particular attention should be paid to pregnant women with co-morbidities because those are at most significant risk of complication both with and without coronavirus infection.When managing a pregnancy, unassisted 4-5 weeks may have a substantial impact on the outcome. Non-adherence to the right timing of acetylsalicylic acid prophylaxis, vaginal progesterone treatment, glucose tolerance test or anti D immunoglobulin injection, can lead to significant complications. Women that suffer from pre-pregnancy morbidities such as hypertension, diabetes, renal problems, obesity are in these times at risk of an even higher risk of adverse outcome due to reduction in surveillance. In their case, there is a need for more than less scrutiny. In this group of women, on the one hand, we fear that restricted access to health care facilities may lead to deterioration of control of blood pressure values, glucose levels or excessive weight gain. On the other hand, they may become exposed to the coronavirus, which again in this group may lead to an adverse outcome, because these women are at higher risk of severe complications associated with the viral infection. As mentioned before, without fully adhering to the recommended protocols for both low and high risk, but especially high-risk pregnancies, the goals of optimal perinatal care cannot be achieved. In the time of the pandemic adherence to protocols is put to the test, and although interim protocols are published by national and international societies to adjust means to the measure, it may not be enough. [8] Two reports [9,10] show the impact of co-morbidities on the percentage of severe cases among infected with COVID-19 pregnant women. In a study from China, 38 women infected with SARS-CoV-2 were analyzed; none of them had pre-pregnancy comorbidities. Of those women, 3 developed gestational diabetes and one hypertension and one preeclampsia during the course of pregnancy. In the New York group, more than 41% demonstrated associated diseases such as asthma, chronic hypertension and type II diabetes. More than 60% of women in the New York group was diagnosed with obesity – a factor neglected in the China group (Table 1). These factors could have a decisive impact on the reported differences regarding the course of the COVID-19 disease, notably since the age of the patients did not differ based on the published data. Analysis of these two studies shows that the course of the viral infection was quite different. In the study group from China, no severe and critical events were observed, and for women in New York, they totalled 14%. From the WHO report from all provinces of China in which 147 pregnant women were analyzed, 8% of severe cases and 1% of critical cases were reported [11]. Despite a relatively small group, these results show that co-morbidities, including obesity, like in the non-pregnant population, decide about the course of the disease in a given age group.Restrictions of access to routine care, fear of exposition, deliberate avoiding of contact with medical personnel, isolation and quarantine orders, and many other factors can lead to hindered pregnancy surveillance. If affecting weight gain, blood pressure and diabetes control in high-risk groups, it may, as a consequence, affect perinatal outcome regardless of COVID-19 infection.The current situation related to the pandemic requires an intensified effort from medical personnel caring for pregnant women. In many cases, new forms of medical care are implemented, such as telephone and video consultations. This cannot always replace traditional perinatal visits but often is a necessity. RCOG warns their pregnant patients to always discuss with their medical professional the decision about not attending their prenatal visit. [12] Regular monitoring of pregnancy is crucial to achieve an optimal outcome. It is the medical community’s responsibility on all levels (local, national, international) not to allow the burdens resulting from epidemiological restrictions to impact negatively the perinatal results achieved thus far.At the beginning of this commentary, we have asked a series of questions. We do not have answers to them. COVID-19 may be the first pandemic in the modern world, but most probably it is not the last. We do not know and cannot tell for how long this situation is going to continue. We propose to begin a discussion of how this can be managed best. Perhaps this should prompt new ideas of how to incorporate telemedicine and artificial intelligence into obstetric practice. The proposed solutions, of course, should be followed by new protocols and laws protecting both the patient and the medical professional.
Fitting a naturally scaled point system to the ACMG/AMP variant classification guidel...
Sean Tavtigian
Ken Boucher

Sean Tavtigian

and 2 more

April 14, 2020
Recently, we demonstrated that the qualitative American College of Medical Genetics and Genomics/ Association for Medical Pathology (ACMG/AMP) guidelines for evaluation of Mendelian disease gene variants are fundamentally compatible with a quantitative Bayesian formulation. Here, we show that the underlying ACMG/AMP “strength of evidence categories” can be abstracted into a point system. These points are proportional to Log(odds), are additive, and produce a system that recapitulates the Bayesian formulation of the ACMG/AMP guidelines. Strengths of this system are its simplicity and that the connection between point values and odds of pathogenicity allows empirical calibration of strength of evidence for individual data types. Weaknesses include that a narrow range of prior probabilities is locked in, and that the Bayesian nature of the system is inapparent. We conclude that a points-based system has useful attributes of user friendliness and can be useful so long as the underlying Bayesian principles are acknowledged.
A Comparison of Quantum and Traditional Fourier Transform Computations
Damian Musk

Damian Musk

November 23, 2020
The quantum Fourier transform (QFT) can calculate the Fourier transform of a vector of size N with time complexity 𝒪(log²N) as compared to the classical complexity of 𝒪(NlogN). However, if one wanted to measure the full output state, then the QFT complexity becomes 𝒪(Nlog²N), thus losing its apparent advantage, indicating that the advantage is fully exploited for algorithms when only a limited number of samples is required from the output vector, as is the case in many quantum algorithms. Moreover, the computational complexity worsens if one considers the complexity of constructing the initial state. In this paper, this issue is better illustrated by providing a concrete implementation of these algorithms and discussing their complexities as well as the complexity of the simulation of the QFT in MATLAB.
How and when should subspecies be defined? Analyses of geographical populations of th...
Zhengzhen Wang
Zixiao Guo

Zhengzhen Wang

and 6 more

April 14, 2020
The designation of subspecies has long been controversial in systematics. In addition to phenotypic divergence, subspecies designation may need to incorporate population genetic analyses. In this study, we perform such a survey on three subspecies of the mangrove tree Avicennia marina, distributed along the Indo-West Pacific coasts. Samples from 16 populations (577 individuals) were collected and 94 nuclear genes were sequenced. We identify four genetic features that support the subspecies designation in this genus. First, genetic divergence that delineates the three subspecies is evident, with discordance found mainly in zones of secondary contact. Moreover, levels of genetic diversity within local populations differ among subspecies. Second, the three subspecies have separate demographic histories inferred by computational modeling. Third, gene flow is detected between subspecies indicating little or no reproductive isolation. Fourth, the delineation of the subspecies varies from locus to locus across the genome, thus hinting continual but uneven exchanges of genes. All these features indicate that the three taxa have proceeded far beyond structured populations. Since they have not satisfied the criteria for full-species designation, the subspecies designation is warranted. We believe these considerations can be generalized to other taxa.
Predictions of coronavirus incidence in New Zealand
Arindam Basu

Arindam Basu

April 14, 2020
Coronavirus predictions in NZ and othersNew Zealand is one of the few countries that seem to have got a control over the recent covid19 outbreak.\cite{james_suppression_nodate} Here we present the incidence of Coronavirus in New Zealand and some predictions as to how and when we can expect to get to a point of zero incident cases in NZ. We used the  incidence  package within R statistical software to create incidence objects\cite{Kamvar_2019}  from data obtained from the JHU CSSE covid19 archives, and use  the graphs to obtain these estimates. We used a realistic estimate of R0 2.4 for the first four weeks of the projected numbers and a series of effect reproductive numbers of 0.70 and 0.90 for the downward trend \cite{dietz_estimation_1993}.
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