bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel Pet‐Degrading Enzymes: Structure‐Function from a Computational Perspective
Authors: Berselli Alessandro , Ramos Maria J. , Menziani Maria Cristina 
Published: January 2021

AbstractThe bacterium strain Ideonella sakaiensis 201‐F6 is able to hydrolyze low‐crystallinity PET films at 30 °C due to two enzymes named PETase and MHETase. Since its discovery, many efforts have been dedicated to elucidating the structure and features of those two enzymes, and various authors have highlighted the necessity to optimize both the substrate binding site and the global structure in order to enhance the stability and catalytic activity of these PET biocatalysts so as to make them more suitable for industrial applications. In this review, the strategies adopted by different research groups to investigate the structure and functionality of both PETase and MHETase in depth are described, emphasizing the advantages provided by the use of computational methods to complement and drive experiments. Subsequently, the modifications implemented with protein engineering are discussed. The versatility of the enzymes secreted by I. sakaiensis enables the prediction that they will find several applications in the disposal of PET debris, encouraging a prioritization of efforts in this prolific research field.
Potential surrogate quantitative immunomodulatory potency assay for monitoring human umbilical cord‐derived mesenchymal stem cells production
Authors: Teng Sen‐Wen , Sung Hsin‐Yu , Wen Yu‐Chieh , Chen Ssu‐Yu , Lovel Ronald , Chang Wen‐Ying , Wu Tang Bo‐Chung , Hsuan Yogi Cheng‐Yo , Lin Willie 
Published: January 2021

AbstractMesenchymal stem cells (MSCs) play an important role as immune modulator through interaction with several immune cells, including macrophages. In this study, the immunomodulatory potency of human umbilical cord‐derived mesenchymal stem cells (hUC‐MSCs) was demonstrated in the in vivo middle cerebral artery occlusion (MCAo)‐induced brain injury rat model and in vitro THP‐1‐derived macrophages model. At 24 h after induction of MCAo, hUC‐MSCs was administered via tail vein as a single dose. Remarkably, hUC‐MSCs could inhibit M1 polarization and promote M2 polarization of microglia in vivo after 14 days induction of MCAo. Compared with THP‐1‐derived macrophages which had been stimulated by lipopolysaccharide, the secretion of proinflammatory cytokines, tumor necrosis factor‐α (TNF‐α) and interferon‐γ inducible protein (IP‐10), were significantly reduced in the presence of hUC‐MSCs. Moreover, the secretion of anti‐inflammatory cytokine, interleukin‐10 (IL‐10), was significantly increased after cocultured with hUC‐MSCs. Prostaglandins E2 (PGE2), secreted by hUC‐MSCs, is one of the crucial immunomodulatory factors and could be inhibited in the presence of COX2 inhibitor, NS‐398. PGE2 inhibition suppressed hUC‐MSCs immunomodulatory capability, which was restored after addition of synthetic PGE2, establishing the minimum amount of PGE2 required for immunomodulation. In conclusion, our data suggested that PGE2 is a crucial potency marker involved in the therapeutic activity of hUC‐MSCs through macrophages immune response modulation and cytokines regulation. This study provides the model for the development of a surrogate quantitative potency assay of immunomodulation in stem cells production.
Disparate impact of severe aortic and mitral regurgitation on left ventricular dilation
Authors: Schott Jason P. , Dixon Simon R. , Goldstein James A. 
Published: January 2021

AbstractIn asymptomatic severe aortic (AR) and mitral regurgitation (MR), left ventricular (LV) dimension criteria were established to guide timing of valve replacement to prevent irreversible LV dysfunction. Given both lesions are primary LV volume overload ''leaks'', it might be expected that both lesions would induce similar impact on the LV and result in equivalent dimension criteria for intervention. However, the dimension‐based intervention criteria for AR versus MR (developed through natural history studies), differ markedly. The pathophysiological foundations for such discordance have neither been fully elucidated nor emphasized. This case‐based treatise compares the two regurgitant lesions with respect to: (a) ''total regurgitant circuits''; (b) ''driving pressures'' resulting in LV volume overload from each respective ''leak''; and (c) volume and afterload wall stresses imposed on the LV.Key points
The ''total circuits'' of volume overload differ: The AR circuit includes the LV and systemic vasculature, whereas MR includes the LV ejecting into the left atrium/pulmonary veins and systemic circulation.
The ''driving pressure'' of regurgitation and afterload are high with AR and low with MR.
Differing ''total circuits'' and ''driving pressures'' impose disparate wall stresses upon the LV. Parallel and serial sarcomere replication occurs in AR, while only serial replication occurs in MR.
It therefore follows that for regurgitation of similar severities, AR results in greater LV dilation at the point of irreversible myocardial dysfunction compared to MR. These considerations may explain, at least in part, the disparate dimension criteria employed for valve intervention for severe AR vs MR.
800 Gram Infant with A bronchial foreign body
Authors: Alruwaili Abdulmajeed , Payson Allison , Tirado Yamilet 
Published: January 2021

AbstractReport of successful foreign body removal in a micro‐preemie infant utilizing instruments outside of the normal armamentarium. Challenges encountered during the removal process of the foreign body and technique utilized are explained with the intention of providing steps that can be reproducible in a similar clinical setting.
Silica‐Templated Metal Organic Framework‐Derived Hierarchically Porous Cobalt Oxide in Nitrogen‐Doped Carbon Nanomaterials for Electrochemical Glucose Sensing
Authors: Sun Qiuhong , Ding Junyang , Chen Dandan , Han Cheng , Jiang Minghua , Li Ting‐Ting , Hu Yue , Qian Jinjie , Huang Shaoming 
Published: January 2021

AbstractAs glucose molecules are well recognized to supplement the main energy source of living cells as the intermediate product of metabolism in human body, it is of great importance to develop a convenient and quantitative glucose sensor with high selectivity, high sensitivity, and high accuracy. In this work, a simple and novel strategy has been developed to obtain a high‐performance non‐enzymatic glucose sensor by constructing hierarchically porous Co3O4 embedded into the metal organic framework (MOF)‐derived N‐doped carbon matrix based on a SiO2 template, denoted as ST‐Co3O4. The removal of the SiO2 template creates abundant voids and a large specific surface for the obtained layered mesoporous ST‐Co3O4 composite, which enhances the electron transfer kinetics and the ability to adsorb biomolecules, further greatly improving the surface reaction efficiency and promoting the improvement of its catalytic performance. Compared with pure Co3O4 nanoparticles from ZIF‐67 without a silica template, as‐obtained ST‐Co3O4 shows a good mesoporous environment, provides more active sites, and makes the non‐enzymatic glucose sensor exhibit high sensitivity (2860 μA mM−1 cm−2) and fast response time (<1 s) over a wide linear glucose concentration range of 1.0–1300.0 μM. Additionally, the ST‐Co3O4/CC electrode demonstrates good anti‐interference, high repeatability, and robust stability (>3000 s), which can repeatedly detect the glucose species in real human serum (RSD<9.69 %, n=3), and shows broad prospects in non‐enzymatic sensors.
PROTOCOL: Water, sanitation and hygiene for reducing childhood mortality in low‐ and middle‐income countries
Authors: Sharma Waddington Hugh , Cairncross Sandy 
Published: January 2021

AbstractRespiratory tract infections and diarrhoea are the two biggest killers of children in low income contexts. They are closely related to access to, and use of improved water, sanitation and hygiene (WASH). However, there is no high quality systematic review that quantifies the effect of WASH improvements on childhood mortality. Existing systematic reviews of WASH improvements measure effects on morbidity, under the (often implicit) assumption that morbidity is closely correlated with mortality. This is at least partly because the impact evaluations on which they are based are only designed to detect changes in morbidity with statistical precision, whereas mortality is a relatively rare outcome. The proposed review will address this evidence synthesis gap, using the greater statistical power of meta‐analysis to pool findings across studies.
Remote magnetic‐guided ablation for three origins of idiopathic ventricular arrhythmias with right bundle branch block and superior axis
Authors: Li Xiang , Shang Wentao , Zhang Ning , Xie Yun , Wei Yue , Lin Changjian , Ling Tianyou , Chen Kang , Pan Wenqi , Wu Liqun , Bao Yangyang , Jin Qi 
Published: January 2021

AbstractBackgroundIdiopathic ventricular arrhythmias (IVAs) with right bundle branch block (RBBB) and superior axis commonly originate from posterior mitral annulus (PMA), the left ventricular (LV) posterior fascicle (LPF), and the LV posterior papillary muscles (PPM).HypothesisRemote magnetic navigation (RMN)‐guided ablation might be safe and effective for these three origins of IVAs.MethodsThirty consecutive IVA patients with RBBB and superior axis (11 MPA‐IVAs, 11 LPF‐IVAs, and 8 PPM‐IVAs) were included in this study. Electrical mapping and ablation with RMN were performed in the LV through a trans‐septal approach. Navigation index, defined as the ratio of total radiofrequency (RF) time and the time from first burn to last burn, was used to determine the efficiency of RMN‐guided ablation.ResultsThe overall acute success rate was achieved in 93% (PMA, 100%; LPF, 91%; PPM, 88%; p > 0.05). No complication occurred in this study. The procedure time of PPM‐IVAs group was 34 and 14 min longer when compared with MPA‐IVAs and LPF‐IVAs group, respectively, without an increase of X‐ray time. The mean navigation index was 0.45 ± 0.20. The PPM‐IVAs group had an underperforming navigation index value (0.29 ± 0.11) (p < 0.01), as longer RF time was required in the PPM‐IVAs group.ConclusionsRMN‐guided ablation can achieve a high acute success rate for IVAs with RBBB and superior axis. The lower navigation index for PPM‐IVAs indicated that increasing the RF time and improving the catheter contact should be considered when using RMN.
Nonaspirin nonsteroidal anti‐inflammatory drugs and gastric cancer risk after Helicobacter pylori eradication: A territory‐wide study
Authors: Li Bofei , Cheung Ka Shing , Wong Ian Yu‐Hong , Leung Wai Keung , Law Simon 
Published: January 2021

BackgroundDespite Helicobacter pylori (HP) eradication, individuals can still develop gastric cancer (GC). Prior studies have demonstrated that nonaspirin nonsteroidal anti‐inflammatory drugs (NA‐NSAIDs) reduce the risk of GC, but this may be caused by immortal time bias and failure to adjust for HP status. The objective of this study was to investigate whether NA‐NSAIDs reduced the risk of GC in patients who undergo H. pylori eradication.MethodsAdult patients who had received clarithromycin‐based triple therapy between 2003 and 2016 were identified from a territory‐wide health care database. Exclusion criteria included prior GC or GC diagnosed <6 months after HP eradication, prior gastrectomy, gastric ulcer after HP eradication, and failure of triple therapy. Covariates included age, sex, prior peptic ulcer disease, other comorbidities, and concurrent medications (aspirin, proton pump inhibitors, statins, and metformin). To avoid immortal time bias, NA‐NSAID use (≥90 days) was treated as a time‐dependent variable in a multivariable Cox model (time‐dependent analysis). Time‐independent analysis was also performed.ResultsDuring a median follow‐up of 8.9 years (interquartile range, 5.4‐12.6 years), 364 of 92,017 patients (0.4%) who underwent HP eradication developed GC. NA‐NSAID use was associated with a significant reduction in the risk of GC in time‐fixed analysis (adjusted hazard ratio [aHR], 0.65; 95% CI, 0.47‐0.90), but not in time‐dependent multivariable analysis (aHR, 1.35; 95% CI, 0.97‐1.87). Time‐dependent subgroup analyses also did not indicate any significant association between NA‐NSAID use and either cardia GC (aHR, 0.75; 95% CI, 0.27‐2.06) or noncardia GC (aHR, 1.28; 95% CI, 0.83‐1.98).ConclusionsNA‐NSAID use was not associated with a reduced risk of GC among patients who underwent HP eradication. The chemopreventive effect of NA‐NSAIDs observed in prior studies may have been confounded by immortal time bias.
Derivation of Mesenchymal Stromal Cells from Ovine Umbilical Cord Wharton's Jelly
Authors: Carreras‐Sánchez Irene , López‐Fernández Alba , Rojas‐Márquez Raquel , Vélez Roberto , Aguirre Màrius , Vives Joaquim 
Published: January 2021

AbstractThe methods described herein allow for the isolation and expansion of fibroblastic‐like ovine Wharton's jelly‐derived mesenchymal stromal cells (oWJ‐MSC) that, similarly to their human counterparts, adhere to standard plastic surfaces in culture; show a mesenchymal profile for specific surface antigens (i.e., positive for CD44 and CD166); and lack expression of endothelial (CD31) and hematopoietic (CD45) markers as well as major histocompatibility complex (MHC) class‐II. Homogeneous cell cultures result from a two‐phase bioprocess design that starts with the isolation of mesenchymal stromal cells (MSC) from the Wharton's jelly of ovine umbilical cords up to a first step of cryopreservation. The second phase allows for further expansion of ovine WJ‐MSC up to sufficient numbers for further studies. Overall, this methodology encompasses a 2‐week bioprocess design that encompasses two cell culture passages ensuring sufficient cells for the generation of a Master Cell Bank. Further thawing and scale expansion results in large quantities of oWJ‐MSC that can be readily used in proof of efficacy and safety studies in the preclinical development stage of the development of cell‐based medicines. © 2021 Wiley Periodicals LLC.This article was corrected on 18 July 2022. See the end of the full text for details.Basic Protocol 1: Isolation and expansion of ovine mesenchymal stromal cells from Wharton's jelly of the umbilical cordBasic Protocol 2: Characterization of ovine mesenchymal stromal cellsBasic Protocol 3: Growth profile determination of ovine mesenchymal stromal cells from Wharton's jelly
Chemical Synthesis of a Locked Nucleic Acid–Substituted Dinucleotide Cap Analog
Authors: Shanmugasundaram Muthian , Senthilvelan Annamalai , Kore Anilkumar R. 
Published: January 2021

AbstractThis article describes a reliable and efficient method for synthesis of the dinucleotide cap analog m7(LNA)G[5′]ppp[5′]G containing a locked nucleic acid moiety. The required LNA intermediate for the final coupling reaction, m7(LNA)GDP, is prepared in six steps starting from 5′‐DMTr‐N‐DMF LNA guanosine. The overall reaction involves removal of DMTr and DMF groups, 5′ monophosphorylation, imidazolide formation, diphosphorylation, and regioselective m7 methylation. The final coupling reaction of m7(LNA)GDP with ImGMP in the presence of zinc chloride as a catalyst affords m7(LNA)G[5′]ppp[5′]G in 59% yield. © 2021 Wiley Periodicals LLC.This article was corrected on 18 July 2022. See the end of the full text for details.Basic Protocol: Synthesis of an LNA‐substituted dinucleotide cap analogSupport Protocol: Preparation of the tris(tributylammonium) phosphate linker
Corporate social responsibility performance and information asymmetry: The moderating role of analyst coverage
Authors: Naqvi Syeda Khiraza , Shahzad Faisal , Rehman Ijaz Ur , Qureshi Fiza , Laique Usama 
Published: January 2021

AbstractThe study investigates the moderating effect of analyst coverage on the relationship between corporate social responsibility performance and information asymmetry. Data for the period 2008–2018 encompass 208 listed firms from nine different sectors in China. The study employs the fixed effect regression to identify dynamic relationships. The findings suggest that firms engaged in corporate social responsibility activities confront a lower level of information asymmetry. The results also indicate that analyst coverage moderates the relationship between corporate social responsibility performance and information asymmetry and that analyst coverage may play an imperative role in reducing the level of information asymmetry for the firm. Our findings advance the understanding of the association between corporate social responsibility performance and information asymmetry with the moderating effect of analyst coverage. The study investigates the moderating effect of analyst coverage on the relationship between corporate social responsibility performance and information asymmetry. Data for the period 2008–2018 encompass 208 listed firms from nine different sectors in China. The study employs the fixed effect regression to identify dynamic relationships. The findings suggest that firms engaged in corporate social responsibility activities confront a lower level of information asymmetry. The results also indicate that analyst coverage moderates the relationship between corporate social responsibility performance and information asymmetry and that analyst coverage may play an imperative role in reducing the level of information asymmetry for the firm. Our findings advance the understanding of the association between corporate social responsibility performance and information asymmetry with the moderating effect of analyst coverage. Moreover, present study contributes to the corporate social responsibility practices in China, it provides a sound base for policymakers for adopting corporate social responsibility performance activities.
Demography_Lab, an educational application to evaluate population growth: Unstructured and matrix models
Authors: Arrontes Julio 
Published: January 2021

AbstractTraining in Population Ecology asks for scalable applications capable of embarking students on a trip from basic concepts to the projection of populations under the various effects of density dependence and stochasticity. Demography_Lab is an educational tool for teaching Population Ecology aspiring to cover such a wide range of objectives. The application uses stochastic models to evaluate the future of populations. Demography_Lab may accommodate a wide range of life cycles and can construct models for populations with and without an age or stage structure. Difference equations are used for unstructured populations and matrix models for structured populations. Both types of models operate in discrete time. Models can be very simple, constructed with very limited demographic information or parameter‐rich, with a complex density‐dependence structure and detailed effects of the different sources of stochasticity. Demography_Lab allows for deterministic projections, asymptotic analysis, the extraction of confidence intervals for demographic parameters, and stochastic projections. Stochastic population growth is evaluated using up to three sources of stochasticity: environmental and demographic stochasticity and sampling error in obtaining the projection matrix. The user has full control on the effect of stochasticity on vital rates. The effect of the three sources of stochasticity may be evaluated independently for each vital rate. The user has also full control on density dependence. It may be included as a ceiling population size controlling the number of individuals in the population or it may be evaluated independently for each vital rate. Sensitivity analysis can be done for the asymptotic population growth rate or for the probability of extinction. Elasticity of the probability of extinction may be evaluated in response to changes in vital rates, and in response to changes in the intensity of density dependence and environmental stochasticity.
3‐(4‐Carboxybenzoyl)quinoline‐2‐carboxaldehyde labeling for direct analysis of amino acids in plasma is not suitable for simultaneous quantification of tryptophan, tyrosine, valine, and isoleucine by CE/fluorescence
Authors: Ta Hai Yen , Perquis Lucie , Sarazin Cédric , Guiard Bruno , Meang Varravaddheay Ong , Collin Fabrice , Couderc François 
Published: January 2021

AbstractCapillary electrophoresis coupled to LED‐induced fluorescence detection is a robust and sensitive technique used for amino acids (AA) analysis in biological media, after labeling with 3‐(4‐carboxybenzoyl)quinoline‐2‐carboxaldehyde (CBQCA). We wanted to quantitate in plasma tryptophan (Trp), tyrosine (Tyr), valine (Val), and isoleucine (Ile). Among the different labeled AA‐CBQCA, Trp has the lowest fluorescence yield, which makes its detection and quantification very difficult in biological samples such as plasma. We tried to improve Trp analysis by CE/LED‐induced fluorescence detection to its maximal sensitivity by using large volume sample stacking as a preconcentration step in our analytical protocol. At pH 9.5, this step caused a drop in resolution during the separation of the four AAs and it was therefore necessary to work at pH 10. We have found that Tyr, Val, Ile, and Trp are detected and well separated from the other AAs, but Trp cannot be quantified in plasma samples, mainly because of the low fluorescence yield of the Trp‐CBQCA derivative. The recorded LOD is 0.18 μM for Trp‐CBQCA in standard solution with a resolution between Trp and Tyr of 1.2, while the LOD is 6 μM in plasma with the same resolution.Trp, Tyr, Val, and Ile are, however, efficiently quantified when using a 3 M acetic acid electrolyte and CE associated with capacitively coupled contactless conductivity detection, which also has the advantage of not requiring derivatization or large volume sample stacking. This article demonstrates, for the CE user, that quantitative analysis of these four AA in mouse plasma can be performed by CE‐fluorescence after CBQCA labeling, with the exception of Trp. It can be advantageously replaced by CE/capacitively coupled contactless conductivity detection, the only efficient one for Trp, Tyr, Val, and Ile quantification. In this case, the LOD for Trp is 2 μM. The four AAs are separated with resolution with neighbors above 1.5.