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Simulating streamflow in ungauged catchments using regionalization methods in southea...
Afshin Jahanshahi
Kaka Shahedi

Afshin Jahanshahi

and 4 more

July 07, 2020
Simulating streamflow in ungauged catchments is a challenge for the management of surface water resources around the world, especially in dry regions. Here, we transfer parameters of two HBV and IHACRES hydrological models from gauged (donor) to ungauged catchments using three main regionalization approaches including Physical Similarity (PS), Multiple Regression (MR), Spatial Proximity (SP) and an integrated approach, which is basically an extension of PS approach through Inverse Distance Weighted (IDW) method (IDW-PS). We use a set of 21 catchments in Hamoun-Jazmourian River Basin in southeast Iran, to compare regionalization approaches. The results indicate that (1) generally, the HBV model performs slightly better than IHACRES model in calibration, verification, and regionalization, (2) the physical similarity method under 2 to 4 donor catchments and multiple regression method provide the best and least satisfactory results respectively. The IDW-PS method improves the performance of IDW method, (3) for the physical similarity, eight Catchment Descriptors (CDs) in four main groups of climate, physiographic, location, and land use perform best in prediction performance, (5) the HBV parameters related to snow and runoff components, are associated with highest and lowest uncertainties respectively. For the IHACRES, the most and least robustness parameters are plant stress threshold factor, f and the proportion of slow flow to total flow, vs respectively. Testing the parameter transferability using main approaches of regionalization at two distinct climate regions located in such an extensive river basin is a novelty. The results suggest that the methodology used in this study is rather suitable to simulate streamflow time series of ungauged catchments in the southeast Iran. However, further research is still needed to use this approach in other river basins of Iran.
The allometry of plant height explains species loss under nitrogen addition
Yao Xiao
Xiang Liu

Yao Xiao

and 4 more

July 07, 2020
Light asymmetry, with a higher light acquisition per unit biomass for larger plants, has been proposed as a major mechanism of species loss after nitrogen addition. However, solid evidence for this has been scarce. We measured the allometric size-height relationships of 25 plant species along a nitrogen addition gradient manipulated annually for eight years in a speciose alpine meadow and found that the rare species advantage of light acquisition (i.e., low height scaling exponent) in natural conditions disappeared after nitrogen addition. Those species failing to lower their height scaling exponents decreased in relative abundance after nitrogen addition, thereby decreasing the community weighted mean and dispersion of the height scaling exponent and ultimately the species richness. Our results provided some unique evidence for light asymmetry induced species loss after nitrogen addition and a new insight from the perspective of allometric growth to explain biodiversity maintenance in the face of global changes.
A guide to use of the term “functional trait”
Mar Sobral

Mar Sobral

July 07, 2020
Functional traits are defined such as traits which affect individual fitness. I argue that the use of the term “functional trait” complicates the progress of the field because all traits are potentially linked to fitness. Obviating the potential link of all traits with fitness is related to dismissing (i) the integration of the phenotype, (ii) the spatio-temporal variation of environmental pressures and (iii) the genotype by environment interaction effect on the phenotype. These conceptual gaps could explain the weak predictive power of many functional ecology studies. I develop here some of the reasons why we should consider that all traits are related to fitness -advocating simultaneously for a change in terminology.
Catheter Ablation of Atrial Tachycardias After Mitral Valve Surgery
Youssef Jalloul
Marwan Refaat

Youssef Jalloul

and 1 more

July 07, 2020
A document by Youssef Jalloul. Click on the document to view its contents.
ANAC044 modulates P reutilization in P deficient Arabidopsis thaliana root cell wall...
Qi Wu
ye Tao

Qi Wu

and 4 more

July 07, 2020
Phosphorus (P) deficiency is a major problem in agriculture, thus identifying factors affecting plant’s ability to reutilize previously assimilated P is a prerequisite for improving the P homeostasis in crops grown with P deficient soil. Here, we report the involvement of a NAC (No apical meristem [NAM], Arabidopsis transcription activation factor [ATAF] and Cup-shaped cotyledon [CUC]) transcription factor in P deficiency resistance in Arabidopsis. Compared to the wild type (WT, Col-0) plants, the anac044 mutant displayed P deficiency resistant phenotype, together with the increasing root length, root and shoot biomass under P deficiency. ANAC044 was frequently expressed, including roots and shoots. Upon P deficient treatment even within 1 d, ANAC044 transcript accumulation was strongly up-regulated. Further analysis revealed that, under P-deficient condition, the cell wall, particularly the pectin of anac044, released more P than that of WT, accompanied by an increment of ethylene production, as a result, more soluble P was available in anac044 root and shoot. Thus, the study here uncovers the role of ANAC044 in maintenance of P homeostasis through ethylene signaling.
Impact assessment of bioclogging on hydraulic conductivity of porous media
Kushal Singh
S, Visali

Kushal Singh

and 4 more

July 07, 2020
Microorganisms can do physical and chemical transformations in the media during their growth in an organic-rich favorable environment. Adequate infiltration of organic-rich water into the porous media such as aquifers may cause intensive microbial activity and clog the pores by microorganisms. A sandbox laboratory experiment has been conducted for understanding impact assessment of bioclogging on the hydraulic properties of the porous media caused by aerobic and anaerobic microbial activities. A tank packed with medium-grained sand was saturated with growth medium prepared by dissolving source of organic matter, nitrate, sulfate, and iron in a tap water. To grow the complex microbial species in the tank, a 10 ml bacterial seed taken from the Winogradsky column was injected in the middle of the tank at a depth of 10 cm. To achieve the preset objective, bacterial population density and hydraulic measurements both in aerobic and anaerobic zones were conducted every 15 days and 30 days, respectively. This study reveals that hydraulic conductivity is initially increased in the aerobic zone and subsequently begins decreasing, whereas, in the anaerobic region, it reduces during the entire period of experimentation. It is also found that the conductivity in the anaerobic zone decreases with an increase in bacterial populations of nitrate, iron, and sulfate reducers. However, in the aerobic zone, hydraulic conductivity increases with an increase in population E.coli due to the dissolution of sand grains induced by aerobic and facultative microorganisms.
Prospects of monoclonal antibodies in COVID-19 treatment: a systematic review.
Emeka Ogiji
Casimir Ofor

Emeka Ogiji

and 9 more

July 07, 2020
Introduction We reviewed the types of monoclonal antibodies being repurposed for COVID-19 therapeutics, the clinical outcomes and adverse effects so as to provide evidence the bedside physicians, the health policy-makers and the general public could employ in the COVID-19 management protocol. Methods This systematic review was conducted following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The Joanna Briggs Institute’s critical appraisal checklists for evaluation of the quality of studies were employed to assess the quality of the different types of primary studies included in the review. Results Our search strategy identified 396 potentially relevant articles which decreased to 322 after duplicates were removed. 281 articles were screened out due to lack of relevance. The full text of the remaining 41 relevant papers were retrieved for full text evaluation after which only 19 studies from eight countries met our eligibility criteria and were included in the review. Majority (42%) of the studies emanated from Italy. Also, 94.7% of the studies used tocilizumab. A total of 698 patients were included in all the studies with a male/female ratio of 1.94:1. 78.9% of the studies stated patients’ co-morbidities which include hypertension (80%), diabetes mellitus (73.3%), cardiovascular disease (53.3%) and obesity (26.7%). 75.9% of the patients recovered. Adverse effects reported included viral myocarditis, bacteraemia, candidaemia and invasive aspergillosis. Conclusion Monoclonal antibodies, especially tocilizumab and eculizumab hold some promise in the treatment of the disease but controlled clinical trials using them as monotherapy are needed to further evaluate this finding.
Therapeutic drug monitoring of biologic agents in inflammatory bowel disease: limits...
Jose María Giráldez-Montero
Jaime González-López

Jose María Giráldez-Montero

and 3 more

July 07, 2020
Since the publication of the American Gastroenterological Association’s (AGA) recommendations in 2017, there have been no significant changes in the biological monitoring recommendations. Lack of evidence on proactive therapeutic drug monitoring (pTDM) over the reactive therapeutic drug monitoring (rTDM) and the absence of recommendations on the individualized dosage methods have been limiting. The aims of this review were to identify updates on TDM strategies and in individualized dosing methods. For the analysis of the TDM strategies and individualized dosing method, a search was carried out in PubMed and Cochrane Central. In TDM case, since 2017. A total of 263 publications were found. Only 7 related to pTDM. Two of them were clinical trials and one systematic review. Of the 8 studies analyzed, 7 found benefit from pTDM over rTDM and one found no difference. Only one study was prospective. Regarding the individualized dosing method, 229 results were found. Population pharmacokinetics was the most widely used technique to explore and develop individual dosage models. It has been used to analyze the influence of factors on drug concentrations (serum albumin, weight… etc. We have not found major changes in TDM strategies. The available evidence is limited and of low quality. Retrospective designs and low power of the studies are the main problems. Population pharmacokinetics methods are the most widely used. But are more used to identify factors that affect drug concentrations than for dosage individualization.
Lockdown, Social Media exposure regarding COVID-19 and the relation with self-assessm...
Ariana-Anamaria Cordos
Sorana D. Bolboacă

Ariana-Anamaria Cordos

and 1 more

July 07, 2020
Introduction. Locking the humanity in their homes, COVID-19 forced people to use the technology at hand to keep informed about the outbreak and to keep close to their loved ones. During this time, even if physical health is theoretically unaffected, keeping calm and sane can be challenging. The aim of this research was to evaluate whether exposure to COVID-19 information available in the digital space has a different impact on the mental condition of Romanian medical staff, compared to general population, particularly searching for depression and anxiety symptoms. Materials and methods. An online survey was conducted from April 6 to 16, 2020 within the Romanian users of Social Media platforms. The questionnaire assessed depression with the WHO-Five Well-Being Index, anxiety with the Generalized Anxiety Disorder Scale and Social Media exposure by asking how often the respondents saw COVID-19 related information on the most popular Social Media channels in Romania. Information about: gender, age, educational level, occupation, area of living and risk category was also collected. The risk categories were defined as no risk, medium risk, and medical staff. Results. Almost 90% of the 402 participants received daily through at least one Social Media channel information related to the COVID-19 outbreak. The Social Media Exposure significantly associated with the risk group only for Facebook and LinkedIn. However, exposure to information regarding COVID-19 was neither associated with anxiety nor depression. No significant association was identified neither between age class and self-assessed anxiety nor self-assessed depression. The self-assessment of depression was significantly more frequent as compared to self-assessment of anxiety. Conclusion. The results of this research are opposite to most of the already published literature. Depression and anxiety could not be correlated with the context of lockdown and excessive COVID-19-related information.
Mechanisms of action and adverse effects of the major therapeutic agents in trial for...
Emeka Ogiji
Obumneme  Ezeanosike

Emeka Ogiji

and 5 more

July 07, 2020
Coronavirus disease 2019, an infectious viral disease caused by severe acute respiratory syndrome coronavirus 2 has been declared a global pandemic by World Health Organisation. The race to find an effective cure for it is on. Most of the candidate drugs in various clinical trials are being re-purposed but none has been approved as at date. It is pertinent for the bedside physicians to understand the mechanisms of action of these agents and their peculiar adverse effects so they are properly guided on the risk/benefit of the drugs they choose in managing COVID-19 patients. In this review, we aimed to review the mechanisms of action and adverse effects of the major drugs in clinical trials for COVID-19 therapeutics. Clinicaltrials.gov, the international clinical trials platform of the WHO, the EU clinical trials register and the Cochrane Central Register of Controlled Trials were searched for registered clinical trials. Studies in therapeutic trials were considered eligible for the work. Frequency table was made for the most common trialled drugs and the mechanisms of actions and adverse effects of the selected drugs were reviewed. 10 studies were selected for review in a descending order of their frequency in different therapeutic trials and these are ritonavir, lopinavir, chloroquine/hydroxychloroquine, interferon, remdesvir, favipravir, umifenovir, darunavir, tocilizumab and methylprednisolone. The bedside physicians need to understand the mechanisms of action of these agents and their peculiar adverse effects so they are properly guided on the risk/benefit of the drugs they choose in managing COVID-19 patients.
International Study on Impact of COVID 19 on Cardiac and Thoracic Aortic Aneurysm Sur...
Mohammed Idhrees
Professor Mohamad Bashir

Mohammed Idhrees

and 3 more

July 07, 2020
Background: The COVID19 pandemic gripped every nation’s healthcare system and provisions on all levels. In cardiac and aortic surgery, as it is with most specialities, elective surgeries were halted. Aims of the study: We captured reflections, contingencies, and current practices across of high-volume centres in cardiac and aortic surgery globally. We also aimed this study to assess decision on prioritization of the surgical patients, the need for personal protection equipment and choice of preoperative investigations in current dynamic and fluid climate. Methods: A validated web-based questionnaire was constructed and was circulated to the international surgeons amongst high volume cardiac and aortic surgery centres. Their intrinsic feedback on decision making, impact of the lockdown and perspectives for the future ahead us all were noted. Mixed method approach was constructed. Qualitative data analysis was introduced to signify the impact globally. Results: Overall, 23 centers from 18 countries participated in this international study. 91.7% of the respondents stopped operating on elective patients during the pandemic. Majority of the surgeons agreed that acute aortic dissection (87.1%) should be operated as emergency procedure and stable triple vessel disease (87.1%) to be considered as elective procedure. Three-fifth (60%) of the respondents relied on CT chest as a preoperative screening modality. Conclusion: In the present climate where there is paucity of evidence, this will give an interim consensus for the cardiac surgeons. With the increase in cumulative number of COVID19 patients, careful utilization of the resources regarding hospital beds and manpower is of paramount importance.
Application of Methylene Blue -Vitamin C-N-acetyl Cysteine for Treatment of Criticall...
daryoush Hamidi Alamdari
Ahmad  Bagheri Moghaddam

daryoush Hamidi Alamdari

and 9 more

July 07, 2020
Introduction: COVID-19 is a global catastrophic event that causes severe acute respiratory syndrome. The mechanism of the disease remains unclear, and hypoxia is one of the main complications. There is no currently approved protocol for treatment. The microbial threat as induced by COVID-19 causes the activation of macrophages to produce a huge amount of inflammatory molecules and nitric oxide (NO). Activation of macrophages population into a pro-inflammatory phenotype induces a self-reinforcing cycle. Oxidative stress and NO contribute to this cycle, establishing a cascade inflammatory state that can kill the patient. Interrupting this vicious cycle by a simple remedy may save critical patients’ lives. Methods: Nitrite, nitrate (the metabolites of NO), methemoglobin, and prooxidant-antioxidant-balance levels were measured in 25 ICU COVID-19 patients and 25 healthy individuals. As the last therapeutic option, five patients were administered methylene blue-vitamin C-N-acetyl Cysteine (MCN). Results: Nitrite, nitrate, methemoglobin, and oxidative stress were significantly increased in patients in comparison to healthy individuals. Four of the five patients responded well to treatment. Discussion: NO, methemoglobin and oxidative stress may play a central role in the pathogenesis of critical COVID-19 disease. MCN treatment seems to increase the survival rate of these patients. Considering the vicious cycle of macrophage activation leading to deadly NO, oxidative stress, and cytokine cascade syndrome; the therapeutic effect of MCN seems to be reasonable. Accordingly, a wider clinical trial has been designed. It should be noted that the protocol is using the low-cost drugs which the FDA approved for other diseases.
“If you do what you always did, you will get what you always got.” RCOG Green-top Gui...
Jan Willem de Leeuw
Oliver Daly

Jan Willem de Leeuw

and 1 more

July 07, 2020
A document by Jan Willem de Leeuw. Click on the document to view its contents.
Abundance of Montane Salamanders Over an Elevational Gradient
Daniel Hocking
John Crawford

Daniel Hocking

and 3 more

July 07, 2020
Climate change is expected to systematically alter the distribution and poEurycea pulation dynamics of species around the world. The effects are expected to be particularly strong at high latitudes and elevations, and for ectothermic species with small ranges and limited movement potential, such as salamanders in the southern Appalachian Mountains. In this study, we sought to establish baseline abundance estimates for plethodontid salamanders (family: Plethodontidae) over an elevational gradient in Great Smoky Mountains National Park. In addition to generating these baseline data for multiple species, we describe methods for surveying salamanders that allow for meaningful comparisons over time by separating observation and ecological processes generating the data. We found that Plethodon jordani had a mid-elevation peak (1500 m) in abundance and Desmognathus wrighti increased in abundance with elevation up to the highest areas of the park (2025 m), whereas Eurycea wilderae increased in abundance up to 1600 m and then plateaued with increasing uncertainty. In addition to elevation, litter depth, herbaceous ground cover, and proximity to stream were important predictors of abundance (dependent upon species), whereas daily temperature, precipitation, ground cover, and humidity influenced detection rates. Our data provide some of the first minimally biased information for future studies to assess changes in the abundance and distribution of salamanders in this region. Understanding abundance patterns along with detailed baseline distributions will be critical for comparisons with future surveys to understand the population and community-level effects of climate change on montane salamanders.
Oviposition of the mosquito Aedes aegypti in forest and domestic habitats in Africa
Siyang Xia
Hany Dweck

Siyang Xia

and 7 more

July 07, 2020
The theory of ecological divergence provides a useful framework to understand the adaptation of many species to anthropogenic (‘domestic’) habitats. The mosquito Aedes aegypti, a global vector of several arboviral diseases, presents an excellent study system. Ae. aegypti originated in African forests, but the populations that invaded other continents have specialized in domestic habitats. In its African native range, the species can be found in both forest and domestic habitats like villages. A crucial behavioral change between mosquitoes living in different habitats is their oviposition choices. Forest Ae. aegypti lay eggs in natural water containers like tree holes, while their domestic counterparts heavily rely on artificial containers such as plastic buckets. These habitat-specific containers likely have different environmental conditions, which could drive the incipient divergent evolution of oviposition in African Ae. aegypti. To examine this hypothesis, we conducted field research in two African locations, La Lopé, Gabon and Rabai, Kenya, where Ae. aegypti live in both forests and nearby villages. We first characterized a series of environmental conditions of natural oviposition sites, including physical characteristics, microbial density, bacterial composition, and volatile profiles. Our data showed that in both locations, environmental conditions of oviposition sites did differ between habitats. To examine potential behavioral divergence, we then conducted field and laboratory oviposition choice experiments to compare the oviposition preference of forest and village mosquitoes. The field experiment suggested that forest mosquitoes readily accepted artificial containers. In laboratory oviposition assays, forest and village mosquito colonies did not show a differential preference towards several conditions that featured forest versus village oviposition sites. Collectively, there is little evidence from our study that environmental differences lead to strong and easily measurable divergence in oviposition behavior between Ae. aegypti that occupy nearby forest and domestic habitats within Africa, despite clear divergence between African and non-African Ae. aegypti.
13C-Metabolic flux ratio analysis of Pseudomonas aeruginosa simultaneously producing...
Rafael Oliveira
Vânia Novello

Rafael Oliveira

and 4 more

July 07, 2020
Pseudomonas aeruginosa is an important platform for simultaneous production of polyhydroxyalkanoates (PHA) and rhamnolipids (RHL). Advances in the understanding of the biosynthesis metabolism of these biocompounds are crucial for increasing yield. 13C-Metabolic Flux Ratio Analysis (13C-MFA) is a technique to estimate in vivo metabolic fluxes ratios. PHA and RHL are essentially non-growth associated products of biotechnological interest and both contain hydroxyalkanoates (HAs), whose labeling patterns could be accessed by GC-MS. In this study, to reveal the relative contributions of the Entner-Doudoroff (ED) pathway and the non-oxidative Pentose Phosphate (PP) pathway to PHA and RHL production, 13C-MFA was performed in Pseudomonas aeruginosa LFM634 when supplied with labeled glucose. This strain lacks both functional EMP and the oxidative PP branch. Labeling patterns in HAs were measured. Experiments with [U-13C] glucose indicated a low flux trough PP pathway. An optimal design of labeling experiment showed that [6-13C] glucose would be the best substrate to enable an estimation of the ED flux with high accuracy. Results of experiments performed with this isotope indicated that about two-thirds of glyceraldehyde 3-phosphate is recycled through a cyclic ED architecture, suggesting that P. aeruginosa utilizes that cycle to regulate the NADPH/Acetyl-CoA ratio for PHA and RHL biosynthesis.
Molecular simulations on the hydration and underwater oleophobicity of zwitterionic s...
Zheng Chen
Mingrui Liao

Zheng Chen

and 3 more

July 07, 2020
Zwitterionic materials have attracted increasing attentions in the underwater super-oleophobic applications for its strong hydration via electrostatic interactions. Herein, molecular dynamics simulations were used to investigate the hydration and underwater oleophobicity of sulfobetaine-terminated self-assembled monolayers (SB-SAMs) with different carbon spacer lengths (CSL) between oppositely charged groups of SB molecules. Simulation results show that the hydration of SB-SAMs is positively dependent on CSL; the underwater oleophobicity is strengthened and then weakened with the increase of CSL, reaching optimal performance when CSL = 3; Adhesion force of oil droplet on SB-SAMs is inversely correlated with their contact angles, reaching the minimum value when CSL = 3. Moreover, the addition of NaCl can weaken the self-association of SB molecules resulted from interactions between cationic and anionic groups, which promotes hydration and enhances underwater oleophobicity of SB-SAMs. These results will benefit for the design of novel zwitterion-based materials for anti-fouling and oil-water separation applications.
Association between acupuncture applied during menstruation and change of menstrual c...
Xuecheng Zhang
zhishun Liu

Xuecheng Zhang

and 6 more

July 07, 2020
Background: Previous studies demonstrated that acupuncture is a safe treatment in general population, however, the safety of acupuncture during menstruation remains controversial. This study aimed to evaluate the safety of acupuncture during menstruation, using change of menstrual cycle as primary outcome. Methods: women who were going to receive at least 12 times acupuncture in the coming one month regardless of diagnosis, and experienced at least one menstruation during the period were recruited from four hospitals in Northern China from March 2017 to March 2018. Patients were followed up 3 menstrual cycles since acupuncture treatment, and data was collected through a questionnaire at baseline and 3 follow-up visits. Chi-square tests and logistic regression were used to test the associations between timing of acupuncture and change of menstrual cycle. Result: there were 373 female patients included in analysis, of which 208(55.8%) had acupuncture during menstruation(AM group) and 165(44.2%) did not(NM group). Nearly one fifth(68, 18.2%) of all patients experienced a change in menstrual cycle. The percentage of patients with changed menstrual cycle in AM group(19.7%) was higher than that of NM group(16.4%), but the difference was not significant(OR 1.254, 95% CI 0.647 to 2.431, P=0.503) when adjusted for age, history of menstrual cycle and diagnose. Conclusion: This study indicated that the rate of menstrual cycle change did not differ among patients who received acupuncture during menstruation or not. However, the interpretation and conclusion of the results should be cautious due to the limitations of the study. Key Words: acupuncture, timing, menstrual cycle change, adverse events, safety
Genomic evidence for parallel adaption to cities
Colin Garroway
Chloe Schmidt

Colin Garroway

and 1 more

July 07, 2020
Urban evolutionary biology is the study of rapid evolutionary change in response to humans and our use of lands to support city dwellers. Because cities are relatively modern additions to the natural world, research on urban evolution tends to focus on microevolutionary change that has happened across a few to many hundreds of generations. These questions still fall under the broad purview of evolutionary ecology. But the severity, rapidity, and replication of environmental changes that drive evolution in this context make it worthy of specific attention. Urban evolution provides the opportunity to study the earliest stages of evolution in a context that is scientifically interesting and societally important. The newness of urban populations and their proximity to natural populations also creates challenges when trying to detect population genetic change. In a From the Cover article in this issue of Molecular Ecology, Mueller et al. (2020) use whole genome resequencing data to address some of these challenges while exploring genetic changes associated with urbanization in 3 replicate urban-rural burrowing owl (Athene cunicularia) populations. Combining multiple approaches across these sample sites Mueller et al. find evidence for selection on genes whose function is related to synapses, neuron projections, brain connectivity, and cognitive function in general. That selection was parallel suggests brain processes were likely important for urban adaptation.
Baladi Churna in Management of Anovulatory factor of Infertility (Avranatmaka Apana V...
Nidhi Bajpai
Kamini Dhiman

Nidhi Bajpai

and 1 more

July 07, 2020
A document by Nidhi Bajpai. Click on the document to view its contents.
Accelerated protein engineering using Vibrio natriegens genetic code expansion
Eden Ozer
Lital Alfonta

Eden Ozer

and 1 more

July 07, 2020
Escherichia coli has been considered as the most used model bacteria in the majority of studies for several decades. However, a new faster chassis is emerging in the form of the fast-growing gram-negative bacterium Vibrio natriegens. Different methodologies, well established in E. coli, are currently being adapted for the Vibrio natriegens in the hope of enabling a much faster platform for general lab-work. Amongst the vast technologies available for E. coli, genetic code expansion, the incorporation of unnatural amino acids into proteins, serves as a robust tool for protein engineering and biorthogonal modifications. Here we designed and adapted the genetic code expansion methodology for Vibrio natriegens and demonstrate an unnatural amino acid incorporation into a protein for the first time in this organism.
Angiographic Scoring System for Predicting Successful Percutaneous Coronary Intervent...
Lian Gong
Hongyu Peng

Lian Gong

and 13 more

July 07, 2020
BACKGROUND No scoring models for IS-CTO have been established because of its in-stent characteristics. The purpose of this study was to develop a scoring model to predict the technical success of recanalizing in-stent chronic total occlusion (IS-CTO) by percutaneous coronary intervention (PCI). METHODS We retrospectively collected data from 474 patients who underwent an IS-CTO PCI from January 2015 to December 2018, consecutively. We selected clinical and angiographic factors and utilized a derivation and validation cohort (4:1 sampling ratio) analysis. Factors with strong correlations with technical failure, according to multivariable analysis, were assigned 1 point, and a scoring system with a 4-point maximum was established. The model was then validated with a validation cohort. RESULTS The overall procedural success rate was 77.4%. On multivariable analysis, the factors that correlated with technical failure were proximal bending (beta coefficient [β] = 2.142), tortuosity (β = 2.622), stent under expansion (β = 3.052), and poor distal landing zone (β = 2.004). The IS-CTO score demonstrated good calibration and excellent predicting capacity in the derivation (receiver-operator characteristic [ROC] area = 0.973 and Hosmer-Lemeshow Chi-squared = 5.252; p = 0.072) and validation (ROC area = 0.976 and Hosmer-Lemeshow Chi-squared =0.916; p = 0.632) cohorts. In the validation subset, the IS-CTO score demonstrated superior performance to the J-CTO and PROGRESS CTO scores for predicting technical success (area under the a curve [AUC] 0.976 vs 0.662 vs 0.579, respectively; difference in AUC between the IS-CTO score and J-CTO score = 0.314, p < 0.01; difference in AUC between the IS-CTO score and PROGRESS score = 0.397, p < 0.01). CONCLUSIONS Our results suggest that the IS-CTO score system is a helpful tool to predict the technical success of IS-CTO PCI. Key words: In-stent chronic total occlusion; Percutaneous coronary intervention; Predicting factor; Scoring sys
Tissue distributions of antiviral drugs impact on their capabilities of reducing vira...
Yan WANG
Lei Chen

Yan WANG

and 1 more

July 07, 2020
Background and Purpose Previously we reported our hypothesis that the high distribution of antiviral drugs in the lung is a key factor that results in reducing viral loads in COVID-19 patients. So far, chloroquine, lopinavir, hydroxychloroquine, azithromycin, favipiravir, ribavirin, darunavir, remdesivir, and umifenovir have been tested in COVID-19 clinical trials. Here we validate our hypothesis by comparing the pharmacokinetics profiles of these drugs and their capabilities of reducing viral load in clinical trials. Experimental approach The RNA-seq data were obtained from public database and re-analyzed and visualized by Single Cell Portal and Seurat. The tissue/plasma ratio of antiviral drugs were calculated by AUC or Mean values that were compiled from publications. Key Results High expression of both ACE2 and TMPRSS2 makes the lung and intestine vulnerable to SARS-CoV-2. Hydroxychloroquine, chloroquine, and favipiravir, which were highly distributed to the lung, were reported to reduce viral loads in respiratory tract of COVID-19 patients. Conversely, drugs with poor lung distributions, including lopinavir/ritonavir, umifenovir and remdesivir, were insufficient to inhibit SARS-CoV-2 replication. Lopinavir/ritonavir might inhibit SARS-CoV-2 in the GI tract according to their distribution profiles. Conclusion and Implications The antiviral drugs should be distributed straight to or accumulate in the lung for reducing viral loads in respiratory tract of COVID-1 9 patients. Additionally, to better evaluate antiviral drugs that target the intestine, the stool samples should also be collected for viral RNA test in the future.
Combating COVID-19 Temperature could be a key
Indrani Roy

Indrani Roy

July 07, 2020
A document by Indrani Roy. Click on the document to view its contents.
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