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Is it safe to remove central lines in patients with platelets less than 20,000/uL
Priya Marwah
Stalin Ramprakash

Priya Marwah

and 10 more

May 07, 2021
Background: Patients with tunnelled CVL may develop blood stream infections which at times are difficult to control without line removal. Concomitant severe thrombocytopenia with platelet transfusion refractoriness is often considered a hard contraindication to any procedure involving a major blood vessel. There is very little literature on the actual clinical risks of tunnelled central line removal in febrile pancytopenic patients. Procedure: We analysed complications and outcomes in all or patients, a total of 52, who underwent CVL removal with platelets <20,000/uL. Results: No bleeding episodes or unplanned transfusions could be associated with CVL removal. No other complications were also reported. All patients had time to hemostasis within 5 minutes of catheter removal. A total 31 patients were febrile at the time of CVL removal, of which 17 became afebrile within 2 days. We found no difference in response when comparing those whose antibiotic therapy was change/escalation versus those who did not. Removal of CVL under local anaesthesia remained complication-free even at platelets counts less than 20.000/uL. With only RDP support 17 lines were pulled out without any complications when platelets were below 5.000. Conclusion: Our findings suggest that central lines can be safely removed with platelet counts less than 20.000/ul and that this may result in enhanced blood stream infection control. This might be particularly relevant to neutropenic patients in this day and age of MDR germs emergence and paucity of new effective antibiotics.
Long-Haul COVID Clinics: a trip without a map.            
Edoardo Cervoni

Edoardo Cervoni

May 10, 2021
Far more intense efforts are needed to identify the characteristics of the long COVID before nourishing the ambition of being able to address the problem effectively. Syndromes are, by definition, heterogeneous and difficult to manage in the absence of a clear understanding of the causal mechanisms. The plethora of symptoms affecting multiple systems exhibited by "long COVID sufferers" suggests several underlying mechanisms1,2,3. In this sense, long COVID is a syndrome par excellence. Being a heterogeneous condition from a pathophysiological point of view requires efforts to improve its understanding, diagnostic accuracy and, above all, establish an effective therapeutic program. The latter cannot be achieved ahead of the antecedent two steps. The National Institute for Health and Care Excellence (NICE), the Scottish Intercollegiate Guidelines Network and the Royal College of General Practitioners have developed a quick guideline for managing the long-term effects of Covid-19. The current guideline lacks essential details, including a comprehensive list of organ complications seen in patients with long COVID, the required investigations, and specific interventions for these complications4,5. It is not clear which speciality could be more suitable for aggregating patients suffering from long COVID. Preliminary to initial referral mandatory exams include FBC, U&E, LFTs, CRP, CK, haematinics, TSH, HbA1c, Calcium, BNP, ECG, CXR, SpO2, RR, HR and temperature. The lack of a specific target underlines the generality of the approach. It leaves us with doubts about what the clinics responsible for managing long COVID are expected to do, at least in the hospital setting. Furthermore, we are moving from the premises of a diagnosis of exclusion. It is even not clear what the overall cost of the initial referral is. Costing should include the charges for the multitude of mandatory tests - often already recently performed, but not within the six weeks antecedent to the referral as per requirement - plus the first hospital consultation charge to the NHS. It also remains to be established what the referring doctor and the patient should expect from the referral, especially in the treatment plan. A cost-benefit analysis – that is, the process used to measure the benefits minus the costs associated - of the long COVID clinics in their current form appears to be lacking. Such analysis should also factor in the opportunity cost in the decision-making process. Opportunity costs are alternative benefits deriving from choosing one alternative over another. In other words, the opportunity cost is the forgone or missed opportunity because of a choice or decision.  The above situation, once again, emphasizes the need for at least more solid diagnostic and pathophysiological premises before proceeding further with clinics and therapeutic programs, other than in a field of scientific research aimed at obtaining more information. In the absence of measures so designed, the long COVID can produce a second crisis of the health system and the job sector in the wake of the pandemic itself. Until we have a better idea of dealing effectively with long COVID, there is a strong case for redirecting any money destined to the Long COVID Clinics to clinical research on long COVID and Primary Care. A golden rule in healthcare is that spending more on prevention, early detection, and better-diagnosing spares patients suffering and leads to less complex and less expensive care later.
Conformational variability in proteins bound to single-stranded DNA: a new benchmark...
Dominique MIAS-LUCQUIN
Isaure Chauvot de Beauchêne

Dominique MIAS-LUCQUIN

and 1 more

May 07, 2021
We explored the Protein Data-Bank (PDB) to collect protein-ssDNA structures and create a multi-conformational docking benchmark including both bound and unbound protein structures. Due to ssDNA high flexibility when not bound, no ssDNA unbound structure is included. For the 143 groups identified as bound-unbound structures of the same protein , we studied the conformational changes in the protein induced by the ssDNA binding. Moreover, based on several bound or unbound protein structures in some groups, we also assessed the intrinsic conformational variability in either bound or unbound conditions, and compared it to the supposedly binding-induced modifications. This benchmark is, to our knowledge, the first attempt made to peruse available structures of protein – ssDNA interactions to such an extent, aiming to improve computational docking tools dedicated to this kind of molecular interactions.
Guidelines for reporting protein modelling studies
Mauno Vihinen

Mauno Vihinen

May 07, 2021
Computational modelling tools are widely used, however, articles describing modelling studies frequently do not contain sufficient details to allow the reader to comprehend the modelling procedure, quality of the produced model and validity of interpretations and predictions made based on the model. Here, guidelines were developed for items that have to be included when reporting studies and results based on protein modelling. A brief and concise checklist of required data items was compiled. These guidelines are simple to follow and apply, but require meticulous description of details, many of which can be placed to supplementary material. Authors have to pay attention to details when reporting modelling process. The generated structural models should be made publicly available, preferably by submitting to one of the existing repositories.
Intelligent polymer droplets eject membranes and drive multimodal-propulsion  of floa...
Pietro Ferraro

Pietro Ferraro

and 2 more

May 10, 2021
Self-propulsion of bodies floating in water is of great interest for developing new robotic and intelligent systems at different scales. Frequently, the propulsion concept has been related to the Marangoni effect often demonstrated through surfactants. Here we show for the first time that polymer droplets, made of appropriate combination of solvent/polymer, can represent a new strategy to activate different functionalities on water. We demonstrate that, by dispensing such intelligent polymer droplets, it is possible to propel motions with different modalities of any class of floating objects made of different shapes/materials. On demand propulsion and self-rotation (free and along a pivot) are reported for different objects. Furthermore, we discovered that meanwhile the object is propelled, polymer membranes can be created through the spreading phenomena on water’s surface. Such thin polymer membranes can cover extensive areas and follow predefined paths as function on the motion assumed. We report preliminary example of possible exploitation of these new combined functionalities induced by the intelligent polymer droplets for propulsion of multiple objects and water cleaning through particles’ capture. In perspective, the droplet can be endowed with intelligence to control the various operations by knowing a priori the exact location of the delivery and its volume.
Avian influenza virus in water: global subtype diversity and spatial distribution pat...
Jessica Mateus-Anzola
Beatriz Martínez-López

Jessica Mateus-Anzola

and 3 more

May 07, 2021
The current COVID-19 pandemic highlights the need for zoonotic infectious disease surveillance. Avian influenza virus (AIV) poses a significant threat to animal and public health due to its pandemic potential. Virus-contaminated water has been suggested as an important AIV spread mechanism among multiple species. Nevertheless, few studies have characterized the global AIV subtype diversity and distribution in environmental water. Therefore, this study aims to provide an updated descriptive and phylogenetic analysis of AIVs isolated in water samples from high risk-sites for influenza outbreaks (i.e., live bird markets, poultry farms, and wild bird habitats) on a global scale. A total of 234 hemagglutinin (HA) gene sequences of 21 subtypes were reported from nine countries between 2003 – 2020. Fourteen AIV subtypes were solely reported from Asian countries. Most of the viral sequences were obtained in China and Bangladesh with 47.44% and 23.93%, respectively. Likewise, the greatest global AIV subtype diversity was observed in China with twelve subtypes. Live bird markets represented the main sampling site for AIV detection in water samples (64.10%), mostly from poultry cage water. Nevertheless, the highest subtype diversity was observed in water samples from wild bird habitats, especially from the Izumi plain and the Dongting Lake located in Japan and China, respectively. Water from drinking poultry troughs evidenced the greatest subtype diversity in live bird markets, meanwhile, environmental water used by ducks had the highest number of different subtypes in poultry farms. The maximum-likelihood phylogenetic tree showed that some HA sequences were closely related among different poultry/wild bird-related environments from different geographic origins. Therefore, the results suggest that even though the availability of HA gene sequences in public-access databases varies greatly among countries, environmental AIV surveillance represents a useful tool to elucidate potential viral diversity in wild and domestic bird populations.
Telomere dynamics in relation to experimentally increased locomotion costs and fitnes...
Els Atema
Arie van Noordwijk

Els Atema

and 2 more

May 07, 2021
Evidence that telomere length (TL) and dynamics can be interpreted as proxy for ‘life stress’ experienced by individuals stems largely from correlational studies. We tested for effects of an experimental increase of workload on telomere dynamics by equipping male great tits (Parus major) with a 0.9 gram backpack for a full year. In addition, we analysed associations between natural life-history variation, TL and TL dynamics. Carrying 5% extra weight for a year did not significantly accelerate telomere attrition. This agrees with our earlier finding that this experiment did not affect survival or future reproduction. Apparently, great tit males were able to compensate behaviourally or physiologically for the increase in locomotion costs we imposed. We found no cross-sectional association between reproductive success and TL, but individuals with higher reproductive success (number of recruits) lost fewer telomere base pairs in the subsequent year. We used the TRF method to measure TL, which method yields a TL distribution for each sample, and the association between reproductive success and telomere loss was more pronounced in the higher percentiles of the telomere distribution, in agreement with the higher impact of ageing on longer telomeres within individuals. Individuals with longer telomeres and less telomere shortening were more likely to survive to the next breeding season, but these patterns did not reach statistical significance. Whether successful individuals are characterized by losing fewer or more base pairs from their telomeres varies between species, and we discuss aspects of ecology and social organisation that may explain this variation.
High-performance interactive scientific visualization with DatoViz via the Vulkan low...
Cyrille Rossant
International Brain Laboratory

Cyrille Rossant

and 2 more

May 17, 2021
IntroductionMost scientific disciplines are facing exponentially increasing amounts of data, which require scalable interactive scientific visualization technology. The development of massively parallel graphics processing units (GPU), fostered by the video game industry and artificial intelligence, represents a remarkable opportunity in this respect.Real-time computer graphics technology has been used in scientific visualization for decades, mostly via OpenGL, a popular open-source graphics library created in 1992. It has been used by many video games, graphics applications, and scientific visualization software. During its first decade, OpenGL provided a fixed function pipeline that was simple to use, but not particularly powerful because of the lack of control of the rendering pipeline. In 2004, OpenGL 2.X introduced a programmable pipeline that gave the user a way to customize the various stages of rendering. Since then, there have been various open-source libraries providing OpenGL-based scientific visualization, mostly focused on 3D rendering. Mayavi is a popular example in Python \cite{Ramachandran_2011}.In 2013, Luke Campagnola, Almar Klein, Cyrille Rossant, and Nicolas P. Rougier wrote a new visualization library: VisPy \cite{np2015}. This library took full advantage of the GL ES 2.x API to achieve both fast and scalable rendering of the most common plotting objects, in both 2D and 3D (lines, scatters, images, colormaps, volumes, meshes, etc.). Within a few years, VisPy reached a large scientific audience and became the main real-time 2D/3D scientific rendering library in Python.Although usage of OpenGL is still widespread in the graphics and scientific communities for legacy reasons, the industry is steadily moving to newer low-level graphics APIs such as Vulkan (Khronos), WebGPU (W3C), Metal (Apple), and DirectX 12 (Microsoft). In this context, VisPy is now facing the same problem as Mayavi faced a few years back: it must decide on its future.The Khronos group introduced the Vulkan API in 2016 (https://www.khronos.org/news/press/khronos-releases-vulkan-1-0-specification). This has been a complete redesign from the ground up to give much more control (compared to OpenGL) and to support all features of the latest GPU hardware. However, Vulkan has a huge barrier to entry: drawing a simple triangle using the Vulkan API directly involves about a thousand lines of code. In particular, all the logic related to the presentation of images to the screen, using a swapchain for double- or triple-buffering, all the synchronization of the different GPU tasks and CPU-GPU interactions in the main rendering loop must be done manually. To leverage the power of Vulkan for applications such as scientific visualization, there is thus a crucial need for intermediate-level libraries that drastically simplify the access to Vulkan.One potential solution isbe to use existing rendering engines such as Ogre (https://www.ogre3d.org/), Unity (https://unity.com/), or Unreal (https://www.unrealengine.com/). However, although scientific visualization and video games do share many similarities, they are quite different in their ends. Games are generally highly dynamic and interactive, whereas scientific visualization is much more static and less interactive (to some extent) and can be indifferently 1D, 2D, or 3D. Furthermore, scientific visualization involves a number of concepts that are generally not present in game engines, such as colormaps, labeled axes, non-cartesian projections, image interpolations, etc. Scientific visualization must also be faithful to the data and this requires a highly precise rendering to achieve high representational accuracy. Besides, it is not unusual to render millions or even billions of points in a scientific visualization — while a modern GPU has no problem rendering such a large collection, the corresponding API must be aware of such extreme cases to ensure proper rendering. All these limitations disqualify typical video game rendering engines as a general purpose API for scientific visualization.This exposes a crucial need for a rendering engine that is to scientific visualization what game engines are to video games: an intermediate-level library that allows developers of custom scientific visualizations, or developers of high-level plotting libraries, to leverage Vulkan without delving into an incredibly complicated low-level API. We report here progress that we have made in the past couple of years towards a cross-platform, cross-language scientific visualization engine that leverages Vulkan for scalable, low-overhead, high-performance scientific visualization.
Speciation in the face of long-range dispersal: population genomic structure within a...
Phillip Shults
Matthew Hopken

Phillip Shults

and 6 more

May 07, 2021
The level of gene flow between diverging lineages ultimately determines the outcome of a speciation event. If secondary contact occurs before this process is complete, reproductive isolation barriers must exist or evolve to prevent hybridization. The selective pressures facilitating and maintaining genetic divergence do not always involve an observable phenotypic response, thus cryptic species form. The inability to distinguish between sibling species can be a particularly serious problem in groups responsible for pathogen transmission. Culicoides biting midges occur almost world-wide and vector many disease-causing pathogens that affect wildlife and livestock. In North America, the C. variipennis species complex contains three currently recognized species, only one of which is a vector, and limited molecular and morphological differences have hindered vector surveillance. Here, genomic methods were used to investigate speciation and genetic structure within this complex. Single nucleotide polymorphism (SNP) data were generated using ddRAD sequencing for 206 individuals originating from 17 locations throughout the United States and Canada. Clustering analyses consistently suggest the occurrence of five putative species with significant differentiation occurring in both sympatric and allopatric populations. Evidence of hybridization was detected in three different species pairings, indicating a lack of pre-zygotic reproductive isolation within the complex. Mitochondrial genes were used to trace the hybrid parentage of these individuals, which illuminated discordance with the SNP data. In this study, we highlight the potential role of geographic, ecological, and behavioral isolation in speciation and in maintaining species boundaries, despite hybridization and long range dispersal.
Ochronotic heart disease leading to severe aortic valve and coronary artery stenosis
Ana Velez
Natalie Gaughan

Ana Velez

and 3 more

May 07, 2021
Cardiac ochronosis is a rare disease, estimated to affect 1 in 250,000 persons. While there is extensive evidence of the musculoskeletal alterations of the disease, cardiac involvement has not been widely studied and most information we currently have derives from case reports and case series. We report the case of a 64-year old patient with a known history of alkaptonuria who presented with dyspnea and weight loss. On evaluation, he was found to have severe aortic stenosis, coronary artery disease, and interventricular septal hypertrophy. Surgery revealed extensive ochronotic pigment deposition affecting the cardiac septum, both internal thoracic arteries, the native coronary arteries, and the aortic valve. Ochronotic heart disease is an often disregarded presentation of alkaptonuria. More information is needed on the course of the disease, as well as long-term outcomes after valve replacement surgery and/or CABG in patients with alkaptonuria.
Calculations of Complex Chemical Reaction Equilibria using Free Energy Minimization a...
Housam Binous
Ahmed Bellagi

Housam Binous

and 1 more

May 07, 2021
In the present paper, we determine the chemical equilibrium compositions for two combustion reactions involving either hydrazine or propane at fixed high pressure and temperature values using several computational approaches. Then, we compute the chemical equilibria for reacting systems under a multitude of temperature and pressure conditions and various initial system compositions. These sensitivity analyses are based on a combination of the method of Lagrangian multipliers and the arc-length continuation technique. Indeed, three industrially relevant case studies are elucidated: (1) the synthesis of ammonia using the Haber process, (2) the gasification of a typical biomass surrogate: glucose using steam and (3) the gasification of cellulose using steam. For all the above reacting systems, our results are benchmarked against their counterparts obtained either from the ubiquitous process simulator: ASPEN-Plus® or from data available in the open literature.
The effect of obturator nerve blockade on oncological outcomes of patients with later...
Ozan Horsanali
Huseyin Eren

Ozan Horsanali

and 6 more

May 07, 2021
Objective: To investigate the effect of obturator nerve blockade on oncological outcomes of patients with a diagnosis of lateral wall localized non-muscle invasive bladder cancer. Materials and Methods: One hundred six patients diagnosed with lateral wall localized non-invasive bladder cancer were evaluated between January 2015 and March 2020 in this retrospective, cross-sectional observational study. The patients were divided into two groups: patients receiving only spinal anaesthesia and those receiving spinal anaesthesia combined with ultrasound-guided obturator nerve blockade. Oncological outcomes of the groups were compared statistically. Results: We observed recurrent tumours in 25 patients (45.5%) in Group 1 and 11 patients (21.6%) in Group 2. In addition, we observed tumour progression in eight patients (14.5%) in Group 1 and two patients (3.9%) in Group 2. We observed statistical significance in differences between groups regarding tumour size, recurrence rate, adequate muscle tissue sampling, the ability for complete resection and persistent obturator reflex. The efficacy rate of obturator blockade was 92.1% in Group 2. One-year recurrence-free survival (RFS) was 98.0% and five-year RFS was 23.5% for Group 1, while they were, respectively, 97.4% and 57.2% for Group 2. Conclusion: The obturator reflex is a common and challenging reflex that may cause major complications and result in unintended consequences such as incomplete resection or tumour recurrence with transurethral resection of bladder tumours. In this study, we demonstrated that combining spinal anaesthesia with obturator nerve blockade for lateral wall localized non-muscle invasive bladder cancer may prevent tumour recurrence and reduce perioperative complications.
Multi-State Diagnosis and Prognosis of Lubricating Oil Degradation using Sticky Hiera...
Monika Tanwar

Monika Tanwar

and 2 more

May 07, 2021
In this study, we present a state-based diagnostic and prognostic methodology for lubricating oil degradation based on a nonparametric Bayesian approach i.e. sticky hierarchical Dirichlet process-hidden Markov model (HDP-HMM). An accurate health state-space assessment for diagnostics and prognostics has always been unobservable and hypothetical in the past. The lubrication condition monitoring (LCM) data is in general segregated only as "healthy or unhealthy", representing a binary state-based perspective to the problem. This two-state performance-based formulation poses limitations to the precision and accuracy of the diagnosis and prognosis for real data wherein there may be multiple states of discrete performance that are characteristic of the system functionality. In particular, the reversible and non-linear time-series trends of degradation data increase the complexity of state-based modeling. We propose a multi-state diagnostic and prognostic framework for LCM data in the wear-out phase (i.e. the unhealthy portion of degradation data) accounting for regular oil replenishment and oil change effects (i.e. nonlinearity in the degradation signal). The LCM data is simulated for an elementary mechanical system with four components. The sticky HDP sets the prior for the HMM parameters. The unsupervised learning over infinite observations and emission then reveals the existence of four discrete health states and helps estimate the associated state transition probabilities. The inferred state sequence provides information relating to the state dynamics which in turn provides further guidance to maintenance decision making. The decision making is further backed by prognostics based on the conditional reliability function and mean residual life estimation.
Snail communities improve submerged macrophytes growth by graze epiphytic algae and p...
Tian Lv
Xin Guan

Tian Lv

and 3 more

May 07, 2021
The relationship between producers (e.g., macrophyte, phytoplankton and epiphytic algae) and snails plays an important role in maintaining the function and stability of the shallow ecosystems. A complex relationship exists among macrophytes, epiphytic algae, phytoplankton and snails. An outdoor mesocosm experiment with two-way factorials was carried out, three species submerged macrophytes (Hydrilla verticillate, Vallisneria natans or one exotic submerged plant Elodea nuttallii) and two grazing treatments (4 snail species present or absent) to elucidate those relationships. The results showed that the snail communities reducing the biomass of phytoplankton and epiphytic algae indirect then enhanced the growth of the submerged macrophytes. The macrophyte with complex architecture supported more snail and epiphytic algae, and snails preferred to feed on native plants. Competition drove snails change the grazing preferences to achieve coexistence, so that led to the assembling of snail communities towards the direction of highest resource utilization.
Molecular Dynamics Simulation of Octacosane for Phase Diagrams and Properties via Uni...
Ling Dai
Pavlo Rutkevych

Ling Dai

and 7 more

May 07, 2021
We used united atom scheme to build three types of crystalline structures for octacosane (C28H58) and carried out molecular dynamic simulations to investigate their properties. By gradual heating the three polymorphs, we successfully reproduced the sequence of experimentally reported crystalline phase, intermediate rotator phase and liquid phase. The obtained structural properties of the phases, such as molecule chain morphology, density, chain tilt angle, cell anisotropy. We revealed three mechanisms which well described the kinetic deformation and expansion during the annealing process. Furthermore, our model successfully predicted the melting temperature and the heat of fusion. We also reproduced characteristics of the rotator phases and the liquid phase, indicating the transferability of the united atom scheme among different condensed phases of octacosane. Our methodology represents an effective and efficient means of numerical study for octacosane and may have implication for other members of the n-alkane family.
No evidence to support the effectiveness of surgical masks compared to respirators in...
saleem mastan
Rahul Geetala

saleem mastan

and 4 more

May 06, 2021
We systematically assessed the evidence comparing surgical facemasks to respirators in the prevention of COVID-19 in HCW providing non AGP care in a hospital setting. We identified only one relevant study which reported no significant difference in COVID-19 infection rates amongst HCWs wearing surgical facemasks or FFP1 face-covers as compared to FFP2 respirators. This was an observational study with substantial methodological deficiencies and highlights the need for high quality evidence. However, until this evidence is available, and given that inadequate mask use may increase the risk of nosocomial infection amongst patients and HCWs, we would recommend respirators for non-AGP care.
A Comparison of L-Dopa and Clonidine Growth Hormone Stimulation Tests in Children wit...
Semih Bolu
Abdulvahit Aşık

Semih Bolu

and 1 more

May 06, 2021
Background: Growth hormone (GH) release is pulsatile, and daytime GH levels are low. GH stimulation tests are therefore needed in cases requiring GH level investigation. The purpose of this study was to compare the results of L-dopa and clonidine GH stimulation tests applied in children with short stature and to identify which of these tests should be primarily selected. Methods: The records of 68 patients aged between 2.5 and 16.6 years presenting to the pediatric endocrinology clinic with short stature and undergoing GH stimulation tests between September 2016 and February 2021 were evaluated retrospectively. Cases with GH levels <10 ng/dl following the first GH stimulation test then underwent the other GH stimulation test. Thirty-four (50%) of the cases in the study consisted of individuals beginning with the clonidine test, while the other 34 (50%) started with the L-dopa test. Results: Seventeen (50%) individuals in whom clonidine was employed in the first test had low GH responses, while a low GH response was determined at the second, L-dopa test, in 15 (88.2%) of these individuals, significant variation being observed between the groups (p< 0.001). Conclusion: GH stimulation tests performed to investigate GHD are laborious and time-consuming. The first stimulation test to be applied to differentiate GHD from ISS must therefore be well selected. The clonidine stimulation test, with higher sensitivity than but similar specificity to the L-dopa test, can be employed as the first test.
Detecting non-random mating or selection in natural populations using multi-locus gen...
Gabe O'Reilly
Oliver Manlik

Gabe O'Reilly

and 5 more

May 06, 2021
New sequencing technologies have opened the door to many new research opportunities, but these advances in data collection are not always compatible with some important methods for data analysis. Fis has been a staple calculation in the field of population genetics. Fis can be used to measure either a departure from random mating, or measure underlying selective pressures for or against heterozygote genotypes. However, when using Next Generation Sequencing (NGS) technology on multi-locus gene families it is often impossible to discern which allelic variants are present at each locus. Some important multi-locus gene families are: the major histocompatibility complex (MHC) in animals; homeobox genes in fungi; or the self-incompatibility genes in plants. This in turn makes it impossible to calculate either locus-specific expected heterozygosity, or observed heterozygosity, both of which are required to calculate Fis. Without the ability to calculate Fis from NGS of multi-locus gene families, we need a new multi-locus measure that will allow us to detect the underlining mating, and selective patterns present in such multi-locus genes. This paper provides such a novel multi-locus measure, called 1His. We demonstrate the accuracy of the 1His equation using simulated data, and two datasets taken from natural populations of dolphins and penguins. The introduction of this new measure is particularly important because of the great interest in mating patterns and selection of multi-locus gene families, such as MHC.
Quantitative evaluation of hemodynamic parameters by echocardiography in patients wit...
Fu-Yong Ye
Yuwen Yang

Fu-Yong Ye

and 5 more

May 06, 2021
Objective: To investigate the value of echocardiography in monitoring hemodynamics of postcardiotomy cardiac shock (PCS) patients before, during, and after weaning from extracorporeal membrane oxygenation (ECMO). Methods: Fifty-two patients were divided into a successful weaning group (Group A, n=23) and non-successful group (Group B, n=29). Hemodynamic parameters measured by echocardiography were collected before, during, and after ECMO. The intra-group changes and inter-group differences were analyzed. Results: In group A, the central venous pressure (CVP), proximal right ventricular outflow tract (RVOT), tricuspid annular plane systolic excursion (TAPSE), velocity of tricuspid valve (TVDV), and systolic velocity of tricuspid annulus (s‘TV) during EMCO were significantly lower than before ECMO. After ECMO, left ventricular ejection fraction (LVEF), systolic velocity of mitral annulus (s‘MV), and velocity-time integral of LV outflow tract (LVOT-VTI) were higher than pre-ECMO, and CVP, LVEF, s‘MV, LVOT-VTI, RVOT, TAPSE, TVDV and s‘TV were higher than during ECMO (all p<0.05). In group B, compared to pre-ECMO, subjects exhibited decreased CVP, RVOT, TAPSE, TVDV and s‘TV during ECMO. TAPSE, TVDV, and s‘TV were continuously lower after ECMO, while CVP and RVOT became higher after ECMO (all p<0.05). After ECMO, LVEF, s‘MV, LVOT-VTI, TAPSE, TVDV and s‘TV in group A were higher than those in group B (all p<0.05). Multiple logistic regression analysis showed that LVEF (OR=1.387, 95%CI: 1.072-1.793, p=0.013) and Tei index (OR=-0.005, 95% CI: 0.000-0.939, p=0.047) were independent factors related to the successfulness of ECMO weaning. Conclusions: Quantitative assessment of both LV and RV by echocardiography is important for ECMO weaning.
Transapical mitral valve repair procedures: primetime for microinvasive mitral valve...
Augusto D'Onofrio
Alessandro Fiocco

Augusto D'Onofrio

and 3 more

May 06, 2021
Introduction: Nowadays micro-invasive procedures (off-pump, beating heart) for mitral valve repair (MVRe) are abruptly expanding with the potential to be adopted as a valuable alternative to surgery. In the present manuscript, the Authors review the available technologies intended to treat mitral regurgitation (MR) through transapical approach, including annuloplasty and chordal repair options. Annuloplasty: To date, Valcare Amend is the only transapical mitral valve (MV) ring to have been implanted in patients. The device allows for stabilization of the annulus through a complete semirigid D-shaped ring. The first-in-human successful procedure was performed in 2016 by our Group and subsequent clinical experience included a total of 14 implanted patients. Currently the technology is under clinical trial evaluation to validate the efficacy and safety profile of the device. Chordal Repair: Beating heart chordal implantation via trans-apical approach is a current feasible, safe and reproducible option. Neochord DS1000 is the most widely used technology in the field, with a solid procedural experience and good results in well-selected patients. Its clinical use has been validated in Europe since 2012, while it is still under clinical investigation in the United States. Harpoon TDS-5 system is a novel technology, recently CE mark approved for clinical use. Conclusions: Transapical micro-invasive technologies are current viable therapies to treat MR in selected patients. Embracing transcatheter MVRe therapies should guide the cardiac surgeon through the new revolution of micro-invasive MV tailored repair.
Lower surgical Apgar score is predictive on delirium in patients following off-pump c...
Liang Yin
Zhen Zhu

Liang Yin

and 6 more

May 06, 2021
Objective To determine the predictive value of surgical Apgar score on delirium postoperatively following OPCABG. Method Intraoperative anesthesia data of patients underwent OPCABG during the period of January 2012 and December 2019 were reviewed and SAS score of each patient was calculated. Relationship between SAS score and postoperative occurrence of delirium were analyzed to determine the underlying mechanism. Results There are a total of 436 patients included with a mean age of 62.8±13.8 and 61.2±16.8 in each group. Patients in Delirium group had significantly higher incidence of heart failure (P=0.043) preoperatively in the Delirium group. No significant difference was observed referring to ASA PS III (P=0.102) and no significant difference was observed in duration of the surgery and anesthesia. Also no significant differences was observed as to dexmedetomidine and propofol use (P=0.256, P=0.278). The mean SAS score was in 4.2±0.8, 7.8±1.2 in two groups respectively (P<0.001) and 96(22.02%) postoperative delirium events were recorded. Patients in Delirium group had much more EBL (P<0.001) while LHR (P=102) showed no significant statistical difference between two groups. Univariate and multivariate regression analysis showed that the intraoperative SAS score was significant predictors of delirium following OPCABG (P<0.001; P<0.001). After adjustment for other clinical predictors, the addition of SAS also improved and the area under the curve to predict delirium was 0.934 (95%CI, 0.907-0.960, P<0.001). Conclusions Intraoperative SAS score is associated with postoperatively following OPCABG and SAS score may be a valuable component to improve preoperative risk stratification of delirium among patient under OPCABG.
Supporting Information for "Learning Assembly Tasks in a Few Minutes by Combining Imp...
Padmaja Kulkarni
Jens Kober

Padmaja Kulkarni

and 3 more

October 18, 2021
This Supporting information includes interactive plots, videos, and data captured while performing evaluation and validation experiments for our paper. 
Aortic balloon for the intraoperative management of placenta accreta spectrum: need f...
Eric Jauniaux
Jie Yan

Eric Jauniaux

and 2 more

May 06, 2021
Aortic balloon for the intraoperative management of placenta accreta spectrum: need for standardised methodology and safety dataIn 2003, Bell-Thomas et al (BJOG 2003;110:1120-1122) reported on the emergency use of a transfemoral aortic occlusion catheter to control massive haemorrhage in a case of caesarean hysterectomy for placenta percreta. This was only the second case published in the international literature on the use of an intra-abdominal aortic balloon occlusion (IABO) in the management of placenta accreta spectrum (PAS) (Paull et al. Anesth Intensive Care 1995;23:731-734). A non-exhaustive Pub-Med literature review of articles published in English on this the topic over the last 20 years, identifies 27 articles, 23 of which come from the Peoples Republic of China, where IABO seems to be increasingly popular in the management of PAS.In brief, IABO involves the insertion of a balloon catheter into the infrarenal abdominal aorta above the aortic bifurcation under fluoroscopy guidance. The procedure is performed in a hybrid operating room or interventional radiology (IR) suite with secondary transfer to the operating room. In all but one study (Zhu et al Biomed Res Int.2017:8604849), the balloon was inflated after delivery of the newborn.All publications so far have been retrospective and most are case-control studies, comparing the outcomes of IABO with those of routine surgical techniques with or without additional procedures such as intra-uterine tamponade. Recently, authors have also started to compare IABO with iliac artery balloon occlusion.Overall, these studies have shown that IABO is associated with reduced estimated blood loss and transfusion requirement, ICU admission and hysterectomy and suggested that IABO is more effective than iliac artery balloon occlusion, presumably as arterial occlusion is more effective.However, there is wide variation between studies in prenatal imaging and clinical selection criteria, intraoperative IR methodology and confirmation of the diagnosis of PAS at birth. For example, the pre-operative fluoroscopy time ranges between 2 and 25 minutes with fetal radiation exposure of 4 to 25 mGy; intraoperative balloon inflation/deflation time varies between 5-10/1 minutes and 45-80/10 minutes. The size of the balloon and the need for transfer between the IR room and the operative theatre is rarely described. Most studies lack histopathology confirmation of the diagnosis and/or stratification by PAS grade.Heterogeneity in methodology and design leads to a high risk of confounding, bias or chance. There is also a high risk that the relationship is not causal. One major concern is the risks-benefit ratio of the use of IABO for both mothers and fetuses, in particular if they do not have PAS. The most commonly reported post-operative complication associated with IABO are arterial thrombosis of the external iliac or the femoral artery. There are no data on the long-term follow of the children born after IABO.In 2018, the expert panel of the RCOG green top guidelines 27a (Jauniaux et al., BJOG.2019;126:e1-e48) concluded that larger studies are necessary to determine the safety and efficacy of IR before this technique can be advised in the routine management of PAS. The 10 new studies published in 2019-2010 on the use of IABO in the management of PAS are insufficient to change this statement.Word count: 499
Late detection of communication between juxtaposed atrial appendages
Shinichi Ishida
Masato Mutsuga

Shinichi Ishida

and 3 more

May 06, 2021
A 40-year-old woman underwent an atrial septal defect closure with juxtaposition of the atrial appendages without communication between both appendages 4 years before presentation. She recently experienced desaturation on exercise, and right-to-left shunt coming from the residual communication between both appendages was found. The residual communication was closed from the right to the left atrium. Herein, we report a rare case of juxtaposition of the atrial appendages with residual communication between them after an atrial septal defect closure.
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