bluuebunny/crossref_metadata_2025 huggingface dataset:
Adsorption behaviors of (–)-epigallocatechin gallate and caffeine on macroporous adsorption resins functionalized with carbazole and N-methylimidazole
Authors: Liu Yongfeng , Liu Yi , Di Duolong
Published: March 2020

Purpose

The purpose of this study is to focus on the preparation of macroporous adsorption resins (MARs) functionalized with carbazole and N-methylimidazole, and adsorption behaviors of (–)-epigallocatechin gallate (EGCG) and caffeine (CAF) on the functionalized MARs.

Design/methodology/approach

Based on the Friedel–Crafts and amination reactions, novel MARs functionalized with carbazole and N-methylimidazole were synthesized and characterized by the BET method. Accordingly, adsorption behaviors and structure-activity relationships for EGCG and CAF were studied in detail.

Findings

The results showed that pseudosecond-order kinetic model was provided with a better correlation for the adsorption of EGCG and CAF onto L-1 and L-2, and pseudofirst-order kinetic model was the most suitable model to illustrate the adsorption process for EGCG and CAF on L-3. The result indicated that Langmuir, Freundlich, Temkin–Pyzhev and Dubinin–Radushkevich isotherms all could better illustrate the adsorption processes of EGCG and CAF on L-1, L-2 and L-3.

Practical implications

This study provides theoretical guidance and technical support for the efficient separation and purification of EGCG and CAF from waste tea leaves by MARs on a large scale. In addition, the results showed that this novel MARs would provide useful help and be used in large-scale production of active ingredients from natural products in the industry and other fields.

Originality/value

Adsorption kinetic models such as pseudofirst-order, pseudosecond-order and intra-particle diffusion kinetic models, and adsorption isotherm models such as Langmuir, Freundlich, Temkin–Pyzhev and Dubinin–Radushkevich isotherms models were adopted to illustrate the adsorption mechanisms of EGCG and CAF. The main driving forces for MARs with no functional groups were pore sieving effects, p–p conjugation effects and hydrophobic interactions, and the other significant driving forces for MARs functionalized with carbazole and N-methylimidazole were electrostatic interactions, ion-dipole and hydrogen bonding interactions. This study might provide scientific references and useful help for large-scale separating and enriching active ingredients in natural products using the technology of MARs with special functional groups.
Digoxin use and following risk of psoriasis: A population‐based cohort study in Taiwan
Authors: Li I‐Hsun , Pan Ke‐Ting , Wang Wei‐Ming , Chien Wu‐Chien , Shih Jui‐Hu , Kao Li‐Ting
Published: March 2020

This study examined the association between digoxin use and subsequent psoriasis risk using a population‐based database in Taiwan. This cohort study enrolled 15 545 digoxin users and 15 545 propensity score‐matched non‐users from the Taiwan National Health Insurance Research Database. Each patient was independently followed up for 5 years to confirm whether they had been diagnosed with psoriasis. Cox proportional hazard regression was used to estimate psoriasis risk among digoxin users. Subgroup and sensitivity analyses were also performed. The psoriasis incidence rates were 3.02 and 2.27 per 1000 person‐years among digoxin users and non‐users, respectively. After adjustment for confounders, psoriasis risk was significantly higher among digoxin users than among non‐users. Notably, in most subgroup analyses, digoxin use tended to increase psoriasis risk, particularly among patients with heart failure, diabetes, hypertension and hyperlipidaemia. Moreover, significantly increased psoriasis risk was noted over 2, 3, 4 and 5 years of digoxin use. In conclusion, our findings confirm that digoxin use increases subsequent psoriasis risk. Thus, physicians should be aware of this association and accordingly estimate the risks and benefits of digoxin use. Nevertheless, some patient variables, such as body mass index and obesity, were unavailable in this study. The findings in this study should be elucidated carefully because the potential effects of these factors could not be considered.
Iron alters Ca2+ homeostasis in doxorubicin‐resistant K562 cells
Authors: Yalcintepe Leman , Erdag Demet , Akbas Fahri , Kucukkaya Bahire
Published: March 2020

Iron is an essential trace element especially in cell proliferation, and growth for various cellular events. An increasing amount of research has shown that iron metabolism is altered in tumour cells which usually have rapid growth rates. However, the number of studies on iron metabolism, and calcium regulation are limited in drug‐resistant tumour cells. Previously, we have shown that modulation of iron metabolism through iron chelation regulated the intracellular calcium, and increased the doxorubicin sensitivity. In the present study, we investigated the effects of iron on mRNA expression profiles of fifteen key genes (IP3R1/2/3, RYR1/2, SERCA1/2/3, NCX1/2/3, PMCA1/2/3, and PMCA4) related to calcium homeostasis in the parental cell line K562 and its subclone doxorubicin‐resistant K562 cells. According to the ΔΔCt method with a two‐fold expression difference (P < .05) as a cut‐off level, although iron showed differential effects on most of the genes, IP3R and PMCA genes were especially determined to have changed significantly. These results show that iron metabolism is an important metabolism due to changes in the expression of genes involved in calcium regulation and is a new perspective to overcome cancer/drug resistance.
The 2018 California Wildfires: Integration of Rapid DNA to Dramatically Accelerate Victim Identification
Authors: Gin Kim , Tovar Jason , Bartelink Eric J. , Kendell Ashley , Milligan Colleen , Willey P. , Wood James , Tan Eugene , Turingan Rosemary S. , Selden Richard F.
Published: March 2020

In November 2018, Butte County, California, was decimated by the Camp Fire, the deadliest wildfire in state history. Over 150,000 acres were destroyed, and at its peak, the fire consumed eighty acres per minute. The speed and intensity of the oncoming flames killed scores of people, and weeks before the fire was contained, first responders began searching through the rubble of 18,804 residences and commercial buildings. As with most mass disasters, conventional identification modalities (e.g., fingerprints, odontology, hardware) were utilized to identify victims. The intensity and duration of the fire severely degraded most of the remains, and these approaches were useful in only 22 of 84 cases. In the past, the remaining cases would have been subjected to conventional DNA analysis, which may have required months to years. Instead, Rapid DNA technology was utilized (in a rented recreational vehicle outside the Sacramento morgue) in the victim identification effort. Sixty‐nine sets of remains were subjected to Rapid DNA Identification and, of these, 62 (89.9%) generated short tandem repeat profiles that were subjected to familial searching; essentially all these profiles were produced within hours of sample receipt. Samples successfully utilized for DNA identification included blood, bone, liver, muscle, soft tissue of unknown origin, and brain. In tandem with processing of 255 family reference samples, 58 victims were identified. This work represents the first use of Rapid DNA Identification in a mass casualty event, and the results support the use of Rapid DNA as an integrated tool with conventional disaster victim identification modalities.
Estimating and accounting for genotyping errors in RAD‐seq experiments
Authors: Bresadola Luisa , Link Vivian , Buerkle C. Alex , Lexer Christian , Wegmann Daniel
Published: March 2020

In non‐model organisms, evolutionary questions are frequently addressed using reduced representation sequencing techniques due to their low cost, ease of use, and because they do not require genomic resources such as a reference genome. However, evidence is accumulating that such techniques may be affected by specific biases, questioning the accuracy of obtained genotypes, and as a consequence, their usefulness in evolutionary studies. Here, we introduce three strategies to estimate genotyping error rates from such data: through the comparison to high quality genotypes obtained with a different technique, from individual replicates, or from a population sample when assuming Hardy‐Weinberg equilibrium. Applying these strategies to data obtained with Restriction site Associated DNA sequencing (RAD‐seq), arguably the most popular reduced representation sequencing technique, revealed per‐allele genotyping error rates that were much higher than sequencing error rates, particularly at heterozygous sites that were wrongly inferred as homozygous. As we exemplify through the inference of genome‐wide and local ancestry of well characterized hybrids of two Eurasian poplar (Populus) species, such high error rates may lead to wrong biological conclusions. By properly accounting for these error rates in downstream analyses, either by incorporating genotyping errors directly or by recalibrating genotype likelihoods, we were nevertheless able to use the RAD‐seq data to support biologically meaningful and robust inferences of ancestry among Populus hybrids. Based on these findings, we strongly recommend carefully assessing genotyping error rates in reduced representation sequencing experiments, and to properly account for these in downstream analyses, for instance using the tools presented here.
Medical marijuana laws and driving under the influence of marijuana and alcohol
Authors: Fink David S. , Stohl Malki , Sarvet Aaron L. , Cerda Magdalena , Keyes Katherine M. , Hasin Deborah S.
Published: March 2020

Aims

Medical marijuana law (MML) enactment in the United States has been associated with increased cannabis use but lower traffic fatality rates. We assessed the possible association of MML and individual‐level driving under the influence of cannabis (DUIC) and also under the influence of alcohol (DUIA).

Design and setting

Three cross‐sectional U.S. adult surveys: The National Longitudinal Alcohol Epidemiologic Survey (NLAES; 1991–1992), the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; 2001–2002), and the NESARC‐III (2012–2013).

Participants

The total n was 118 497: 41 764, 41 184, and 35 549 from NLAES, NESARC, and NESARC‐III, respectively.

Measurements

Across the three surveys, similar questions in the Alcohol Use Disorder and Associated Disabilities Interview Schedule assessed DUIC and DUIA. Ever‐MML states enacted MML between 1991–1992 and 2012–2013 (overall period). Early‐MML states enacted MML between 1991–1992 and 2001–2002 (early period). Late‐MML states enacted MML between 2001–2002 and 2012–2013 (late period). MML effects on change in DUIC and DUIA prevalence were estimated using a difference‐in‐differences specification to compare changes in MML and other states.

Findings

From 1991–1992 to 2012–2013, DUIC prevalence nearly doubled (from 1.02% to 1.92%), increasing more in states that enacted MML than other states (difference‐in‐differences [DiD] = 0.59%; 95% CI = 0.06%–1.12%). Most change in DUIC prevalence occurred between 2001–2002 and 2012–2013. DUIC prevalence increased more in states that enacted MML 2001–2002 to 2012–2013 than in never‐MML states (DiD = 0.77%; 95% CI = −0.05%‐1.59%), and in two early‐MML states, California (DiD = 0.82; 95% CI = 0.06–1.59) and Colorado (DiD = 1.32; 95% CI = 0.11–2.53). In contrast, DUIA prevalence appeared unrelated to MML enactment.

Conclusions

Medical marijuana law enactment in US states appears to have been associated with increased prevalence of driving under the influence of cannabis, but not alcohol.
Cardiovascular immune‐related adverse events: Evaluation, diagnosis and management
Authors: Liu Yingxian , Wu Wei
Published: March 2020

Cardiotoxicities are associated with immune checkpoint inhibitor (ICI) therapy. Recent case series and retrospective studies have shown that cardiac immune‐related adverse events (irAEs) are rare but potentially fatal complications of immunotherapy, with various underlying risk factors such as combinations of different ICIs. High mortality rates and overreactive inflammation have been observed with ICI‐associated cardiotoxicities, highlighting the necessity of baseline and serial evaluations and the identification and management of cardiac irAEs as early as possible. The clinical presentations of irAEs range from asymptomatic cardiac biomarker elevation, myocarditis and pericardial diseases to heart failure and mild to fatal arrhythmia. Troponin measurement and electrocardiogram are sensitive initial tests, whereas cardiac magnetic resonance imaging and endomyocardial biopsy are both gold standard components of the diagnostic criteria. Close monitoring and timely consultation with a cardiologist are important for the diagnosis of ICI‐related cardiotoxicities, with decisions of stopping or rechallenging ICIs and strategies to manage heart injuries. Treatment principles are made according to risk stratifications. The first‐line medication is glucocorticoids of various doses, and the second‐line immunosuppression includes intravenous immunoglobin, antithymocyte globulin and other immunosuppressants, which are recommended in life‐threatening cases or in cases of resistance/no response to steroids.
Understanding the challenges faced by adolescents and young adults with allergic conditions: A systematic review
Authors: Vazquez‐Ortiz Marta , Angier Elizabeth , Blumchen Katharina , Comberiati Pasquale , Duca Bettina , DunnGalvin Audrey , Gore Claudia , Hox Valérie , Jensen Britt , Pite Helena , Santos Alexandra F. , Sanchez Silvia , Alviani Cherry , Garriga‐Baraut Teresa , Knibb Rebecca , Mortz Charlotte G. , Gowland M. Hazel , Timmermans Frans , Roberts Graham
Published: March 2020

Background

Adolescence represents a vulnerable time for individuals with asthma and allergic conditions. They suffer an unexpected degree of morbidity. This systematic review aimed to understand the challenges faced by adolescents and young adults with these conditions.

Methods

A systematic literature search was undertaken across eight databases. References were checked by two reviewers for inclusion. Study data were extracted, and their quality was assessed in duplicate. A narrative meta‐synthesis was undertaken.

Results

A total of 108 papers describing 106 studies were retrieved, most focused on asthma. Five themes were identified across studies: (a) Health‐related quality of life—impairment was associated with poor disease control, psychosocial issues, adolescent‐onset allergic disease and female sex; (b) Psychological factors—asthma and food allergy were associated with anxiety and depression, atopic dermatitis was associated with suicidal ideation, and that parental emotional support may be protective; (c) Adherence—suboptimal adherence was associated with older age, barriers to medication usage, poor symptom perception and failure to take responsibility, and positive factors were routines, simpler treatment regimes, better knowledge and perceptions about medications; (d) Self‐management—facilitated by education, knowledge and a positive attitude; and (e) Supportive relationships—families could modify barriers to adherence and foster positive views about self‐management, adolescents suggested that their peers should be more involved in supporting them, and adolescents also wished to have support from nonjudgemental healthcare professionals.

Conclusions

We have some understanding of the challenges faced by adolescents with asthma, less so for other allergic conditions. This knowledge will be used to support guidelines for managing adolescents.
Hybrid laparoscopic pancreaticoduodenectomy: an Australian experience and a proposed process for implementation
Authors: Pham Helen , Nahm Christopher B. , Hollands Michael , Pang Tony , Johnston Emma , Pleass Henry , Richardson Arthur , Lam Vincent , Yuen Lawrence
Published: March 2020

Background

Laparoscopic pancreaticoduodenectomy (LPD) is gaining interest with several series reporting favourable outcomes. However, there are significant limitations to the successful implementation of LPD programmes in Australian and New Zealand (ANZ) settings. This study presents a local series of consecutive hybrid LPD (HLPD) and a suggested protocol for implementation of an LPD programme in ANZ settings.

Methods

A retrospective review of consecutive patients undergoing HLPD with a laparoscopic resection and open reconstruction performed by a single surgeon at two centres in Sydney, Australia, between February 2014 and October 2019 was undertaken. Data were collected from a prospectively maintained database and patient records.

Results

Eighteen patients underwent HLPD. Median operative time was 370 min, with a median laparoscopic resection time of 253 min. Median length of stay was 11 days. There was no mortality within 90 days. Post‐operative complications included two patients requiring a return to operating theatre for post‐operative pancreatic fistula, and five patients with delayed gastric emptying. Median number of lymph nodes harvested was 13 (interquartile range 11–15.8). Resection margins were negative in 15 patients (83.3%).

Conclusion

HLPD is associated with satisfactory perioperative outcomes and may be feasible as a first step towards eventual implementation of LPD in ANZ hospitals.
Integrating knowledge of ecological succession into invasive alien plant management: A case study from Portugal
Authors: Neto Duarte Liliana , Pinto Gomes Carlos , Marchante Hélia , Marchante Elizabete
Published: March 2020

Aims

Knowledge of invasive alien plant (IAP) ecology and plant community succession (synphytosociology) is crucial for successful restoration and prevention of (re)invasions; nevertheless, these two fields are rarely combined. Our case study aims to demonstrate how they can be integrated, by analysing the variation of IAP distribution within biogeographic territories, identifying the potential native plant communities and the ecological conditions that favour (or prevent) each IAP.

Location

Southern Portugal.

Methods

Several native plant indicators and nine selected IAPs were surveyed in 60 1‐km2 sampling plots across the four biogeographic sectors of the study area. The native plant indicators were then used to identify the vegetation series in which IAPs occurred. Ecological requirements favouring the establishment of each IAP were inferred based on expert knowledge and on the characteristics of published vegetation series and bioclimatic data.

Results

Littoral areas were more invaded, particularly those with sand dune habitats, which are highly dynamic and exposed to disturbance. The most frequent IAPs were Acacia dealbata, Arundo donax, Acacia longifolia and Opuntia ficus‐indica. Riparian vegetation series were the most invaded, especially ash woodlands and willow galleries, as well as the littoral psammophilous cork oak and maritime turbinate juniper series. The most adequate native species to recover each of these invaded communities varies, and examples are provided for each situation.

Conclusions

Integrating knowledge about IAP ecological requirements and the dynamics of native vegetation series can help practitioners select native plants that are more likely to function as efficient natural barriers to (re)invasion, predict areas more prone to invasion by IAPs and establish management priorities.
Review: Social networking sites and associations with depressive and anxiety symptoms in children and adolescents – a systematic review
Authors: Piteo Elena Marie , Ward Kelly
Published: March 2020

Background

Given social networking sites (SNSs) have become a pervasive part of culture; it is critical to understand the ways in which they may be advantageous or detrimental to the mental health of young people. This systematic narrative review examined the relationships between SNS and depressive and anxiety symptoms in the child and adolescent population (5–18 years).

Methods

Four databases were searched, and all articles between January 2005 and March 2019 were identified.

Results

Increased time spent or frequency of SNS use, and problematic and addictive behaviour on SNS were significantly associated with higher levels of depressive symptoms. Two cross‐sectional studies found that increased time spent or frequency of SNS use and higher levels of investment on SNS were significantly associated with higher levels of anxiety symptoms. However, other potential confounding factors could explain the relationship between SNS and depressive and anxiety symptoms, including perceived social support, social comparison and fear of missing out (FoMO).

Conclusions

While there is evidence that there is a relationship between SNS and anxiety and depressive symptoms, the effect size tends to be small and informed by studies of poor quality. Therefore, results should be interpreted cautiously. Methodological issues in conceptualising SNS complicated the findings. Future studies should explore the various conditions by which SNS may either interfere or enhance the development of emotional regulation in young people. These findings help to inform clinicians and educators in targeting vulnerable young people who are at risk of developing mental health problems.
Context dependency of biotic interactions and its relation to plant rarity
Authors: Kempel Anne , Vincent Hugo , Prati Daniel , Fischer Markus
Published: March 2020

Aim

Biotic interactions can determine rarity and commonness of species, however, evidence that rare and common species respond differently to biotic stress is scarce. This is because biotic interactions are notoriously context dependent and traits leading to success in one habitat might be costly or unimportant in another. We aim to identify plant characteristics that are related to biotic interactions and may drive patterns of rarity and commonness, taking environmental context into account.

Location

Switzerland.

Methods

In a multispecies experiment, we compared the response to biotic interactions of 19 rare and 21 widespread congeneric plant species in Switzerland, while also accounting for variation in environmental conditions of the species' origin.

Results

Our results restrict the long‐standing hypothesis that widespread species are superior competitors to rare species to only those species originating from resource‐rich habitats, in which competition is usually strong. Tolerance to herbivory and ambient herbivore damage, on the other hand, did not differ between widespread and rare species. In accordance with the resource‐availability hypothesis, widespread species from resource‐rich habitats where more damaged by herbivores (less defended) than widespread species from resource‐poor habitats—such a growth‐defence trade‐off was lacking in rare species. This indicates that the evolutionary important trade‐off between traits increasing competitive ability and defence is present in widespread species but may have been lost or never evolved in rare species.

Main conclusions

Our results indicate that biotic interactions, above all competition, might indeed set range limits and underlines the importance of including context dependency in studies comparing traits of common and rare or invasive and non‐invasive species.
Changes in working memory influence the transition from reactive to proactive cognitive control during childhood
Authors: Troller‐Renfree Sonya V. , Buzzell George A. , Fox Nathan A.
Published: March 2020

Cognitive control develops rapidly over the first decade of life, with one of the dominant changes being a transition from reliance on ‘as‐needed’ control (reactive control) to a more planful, sustained form of control (proactive control). Although the emergence of proactive control is important for mature behavior, we know little about how this transition takes place, the neural correlates of this transition, and whether development of executive functions influences the ability to adopt a proactive control strategy. This study addresses these questions, focusing on the transition from reactive to proactive control in a cross‐sectional sample of 79 children—forty‐one 5‐year‐olds and thirty‐eight 9‐year‐olds. Children completed an adapted version of the AX‐Continuous Performance Task while electroencephalography was recorded and a standardized executive function battery was administered. Results revealed 5‐year‐olds predominantly employed reactive strategies, whereas 9‐year‐olds used proactive strategies. Use of proactive control was predicted by working memory ability, above and beyond other executive functions. Moreover, when enacting proactive control, greater increases in neural activity underlying working memory updating were observed; links between working memory ability and proactive control strategy use were mediated by such neural activity. These results provide convergent evidence that the transition from reactive to proactive control may be dependent on age‐related changes in neurocognitive indices of working memory and that working memory may influence adopting a proactive control strategy.
Sex‐based differences in fatty acid composition of adult walleye
Authors: Johnston Thomas A. , Wiegand Murray D. , Szmadyla Robin L. , Porteous Lindsay R. , Casselman John M. , Leggett William C.
Published: March 2020

Differences in reproductive strategies of male and female fishes are presumably accompanied by differences in nutrient allocation and predicted to lead to divergence in body composition between the sexes. We compared patterns of variation in fatty acid profiles of lipids extracted from ova, liver, muscle and visceral fat between mature male and female walleye (Sander vitreus) sampled from two wild spawning stocks. Fatty acid profiles differed significantly among body tissues in both males and females, with the strongest contrast between muscle and visceral fat. Significant differences in fatty acid composition between the sexes were found in liver, muscle and visceral fat tissues. Variation among sexes and populations was greater in liver than in the other tissues. Female livers had lower relative abundances of palmitic acid (PA, 16:0) and oleic acid (OA, 18:1(n‐9)), and higher relative abundances of arachidonic acid (ARA, 20:4(n‐6)), eicosapentaenoic acid (EPA, 20:5(n‐3)) and docosahexaenoic acid (DHA, 22:6(n‐3)) compared to male livers. In addition, female muscle had higher relative abundance of OA and lower relative abundance of DHA compared to male muscle. Our results illustrate the differential effects of reproductive demands on the biochemical composition of males and females and have implications for the analysis of fatty acid profiles in studies of wild fish populations.
Haliotis tuberculata, a generalist marine herbivore that prefers a mixed diet, but with consistent individual foraging activity
Authors: Roussel Sabine , Poitevin Pierre , Day Robert , Le Grand Fabienne , Stiger‐Pouvreau Valérie , Leblanc Catherine , Huchette Sylvain
Published: March 2020

While population foraging behaviour of herbivores has been extensively studied, individual choice is still poorly understood. Very few studies have focused on the individual consistency of foraging behaviour in marine herbivores. Because marine ectotherms are strongly influenced by their environment and because a mixed diet is appropriate for herbivores, we hypothesized that Haliotis tuberculata, a large marine gastropod, would not exhibit significant individual consistency in foraging activity and would display generalist food choices. To test these hypotheses, the behaviour of 120 abalone was studied using a choice test of eight macroalgal species over 3 weeks, with video recording 24 hr a day. In addition, primary components, secondary metabolites and toughness of the eight algae were measured. At the population level, food choice was mainly related to the protein composition and the toughness of the macroalgae. We found that H. tuberculata is a generalist species feeding on a variety of algae (IS = 0.64), even if 21% of the individuals can be considered to be specialists. However, in contrast to our hypothesis, highly consistent between‐individual variation was observed in foraging activity (ICC = 0.81 for time spent feeding and ICC = 0.74 for number of feeding visits per day). The high individual consistency of foraging activity has some ecological and evolutionary implications currently not understood for this marine herbivore.
Navigating netnography: A guide for the accounting researcher
Authors: Jeacle Ingrid
Published: March 2020

Netnography (Kozinets) is a new research method that has become increasingly popular within the social sciences. The purpose of this paper is to introduce the accounting scholar to this new methodology and suggest its role in researching issues of accountability. The paper first advocates the significance of the online world as a research site for the accounting scholar and provides a review of the extant accounting literature that has used the internet as a data source. It then summarizes the key components of netnography and reviews the recent scholarship in qualitative accounting that has used this new methodology. Opportunities for future research are subsequently discussed. In particular, the paper promotes the use of netnography for furthering an understanding of accountability, whether that be in private, public, or nonprofit organizations. Advances in technology have created new forms of engagement between corporates and stakeholders and between government and citizens. It has launched new arenas to complain and voice opinion and a plethora of new performance metrics. Netnography offers scholars the methodological tools to research such new modes of accountability in the digital age.
A Guide to Native Mass Spectrometry to determine complex interactomes of molecular machines
Authors: Puglisi Rita , Boeri Erba Elisabetta , Pastore Annalisa
Published: March 2020

Native mass spectrometry is an emerging technique in biology that gives the possibility to study noncovalently bound complexes with high sensitivity and accuracy. It thus allows the characterization of macromolecular assemblies, assessing their mass and stoichiometries and mapping the interacting surfaces. In this review, we discuss the application of native mass spectrometry to dynamic molecular machines based on multiple weak interactions. In the study of these machines, it is crucial to understand which and under which conditions various complexes form at any time point. We focus on the specific example of the iron–sulfur cluster biogenesis machine because this is an archetype of a dynamic machine that requires very specific and demanding experimental conditions, such as anaerobicity and the need of retaining the fold of marginally folded proteins. We describe the advantages, challenges and current limitations of the technique by providing examples from our own experience and suggesting possible future solutions.
Comparing the effects of direct and indirect synchronous written corrective feedback: Learning outcomes and students' perceptions
Authors: Kim YouJin , Choi Bumyong , Kang Sanghee , Kim Binna , Yun Hyunae
Published: March 2020

From a sociocultural perspective, collaborative writing tasks offer opportunities to negotiate in decision‐making processes while also sharing responsibility for the production of a single text (Storch, 2013, Collaborative writing in L2 classrooms. Bristol: Multilingual Matters). Although research has found benefits for such tasks (Storch, 2019, Lang Teach, 52, 40–59; Taguchi & Kim, 2016, Appl Linguist, 37, 416–437), variation in how different types of synchronous written corrective feedback (SWCF) in such a setting impacts students' language learning and their perception of SWCF has not been examined. This study compares the role of direct and indirect SWCF during collaborative writing tasks on the learning of Korean among high beginning‐level students. The study was conducted during an existing beginning level Korean course and focused on three textbook units over 6 weeks. Fifty‐three learners of Korean were assigned to one of three conditions: no feedback, indirect SWCF, or direct SWCF. All students completed a pretest, two collaborative writing tasks, a posttest, and a survey for each unit. At the end of the third unit, students in the feedback groups also participated in an exit interview session. The study targeted a total of 12 linguistic features (e.g., auxiliary verbs), which were the focus of the three textbook units. The amount of feedback and students' responses to the feedback were analyzed in terms of the accuracy of resolution on their writing. Students' learning of these linguistic features was measured using written production tests, and their responses were coded for suppliance of target forms and accurate production of them. Our findings indicate that direct SWCF was more useful in helping students produce accurate writing, but both feedback types were effective in promoting learning of new linguistic features through collaborative writing. In terms of students' perceptions, there seemed to be no difference between the two feedback conditions. The findings of the study are discussed in light of effective ways to implement collaborative writing tasks as well as the provision of SWCF.
Antidepressant mechanism of classical herbal formula lily bulb and Rehmannia decoction: insights from gene expression profile of medial prefrontal cortex of mice with stress‐induced depression‐like behavior
Authors: Zhang Hongxiu , Chi Xiansu , Pan Wenchao , Wang Shijun , Zhang Zhe , Zhao Haijun , Wang Yuan , Wu Zhichun , Zhou Miaomiao , Ma Shan , Zhao Qitao , Ma Ke
Published: March 2020

According to traditional Chinese medicine, lily bulb and Rehmannia decoction (LBRD) is a specialized formula for the treatment of “lily disease”, the symptoms of which resemble the clinical manifestations of major depression. However, the molecular basis of the antidepressant mechanism of LBRD and the quality marker ingredients of LBRD remain unclear. This study aimed to investigate the quality marker ingredients of LBRD and to show the molecular mechanism of its antidepressant activities. In this study, we adopted the chronic unpredicted mild stress paradigm to construct a depression model. High‐performance liquid chromatography (HPLC) was used to determine the levels of the main markers in LBRD. The underlying mechanism of LBRD was explored by measuring neurotransmitter and cytokine levels using enzyme‐linked immunosorbent assay, and by quantifying differentially expressed gene (DEG) of transcriptome in the medial prefrontal cortex (mPFC) tissue through RNA sequencing. HPLC results showed that the average levels of quality marker ingredients of LBRD (ferulic acid, dioscin, verbascoside and catalpol) were 0.00079%, 0.00039%, 0.7% and 1.6% (w/w), respectively. LBRD intervention significantly attenuated the depressive phenotype compared with that in the depressed group. LBRD treatment altered the enriched DEGs in the signaling pathways of γ‐aminobutyric acid (GABA) and glutamate neurotransmitter, synaptic plasticity and axon guidance, circadian rhythm and neural‐immunity. GABAergic and glutamatergic synapses as well as brain‐derived neurotrophic factor (BDNF)/TrkB‐dependent phosphoinositide 3‐kinase (PI3K)/Akt/mammalian target of rapamycin‐1 (mTOR1), might be the main signaling pathways underlying the multi‐target therapeutic effects of LBRD against depression.
The Enrichment Process of Groundwater Fluorine in Sea Water Intrusion Area of Gaomi City, China
Authors: Chen Qiao , Hao Decheng , Gao Zongjun , Shi Mengjie , Wang Min , Feng Jianguo , Deng Qinghai , Xia Lu , Zhang Chunrong , Yu Yongbo
Published: March 2020

A typical area, Gaomi City in China, was chosen to discuss the enrichment process of groundwater fluorine in sea water intrusion area. The groundwater had fluorine levels of 0.09–10.99 mg/L, with an average concentration of 1.38 mg/L. The high‐fluorine groundwater was mainly distributed in the unconsolidated Quaternary sediments, where concentrations in 83.6% of the samples exceeded the national limit of 1.0 mg/L. The groundwater in the Quaternary sediments also had higher levels of Cl−, TDS, Mg2+, and pH and lower levels of Ca2+, Co, Ni, and Cu than that in the bedrock. The groundwater fluorine levels in the Quaternary sediments are positively correlated with Cl−, TDS, Mg2+, pH, and negatively correlated with Ca2+, γCa2+/γMg2+, Co, Ni, Cu. Geochemical indices of Cl− and TDS indicate sea water intrusion in the Quaternary high‐fluorine groundwater area (F− > 1.0 mg/L), while they do not indicate any intrusion in the bedrock area. The chemical weathering of minerals was intensified with the intrusion of sea water. Cation exchange was confirmed to occur in the Quaternary sediments and was promoted by sea water intrusion. Cation exchange consumes part of groundwater Ca2+ and permits more F− dissolving. Consequently, in the Quaternary sediments, the groundwater was supersaturated with CaF2 minerals and undersaturated with MgF2 minerals when F− > 1.0 mg/L, while CaF2 and MgF2 minerals both are undersaturated when F− < 1.0 mg/L. Thus, the chemical weathering of minerals and cation exchange caused by sea water intrusion are the crucial processes controlling the groundwater fluorine levels, which should be considered when the groundwater fluorine enrichment mechanism is discussed along coastal zones.
Annual eradication rate of bismuth‐containing quadruple therapy as second‐line treatment forHelicobacter pyloriinfection: A 15‐year prospective study at a tertiary hospital in Korea
Authors: Yoon Kichul , Kim Nayoung , Lee Jung Won , Yoon Hyuk , Shin Cheol Min , Park Young Soo , Lee Dong Ho
Published: March 2020

Background

Bismuth‐containing quadruple therapy is widely used as second‐line treatment forHelicobacter pyloriinfection. This prospective study investigated the changes in the annualH. pylorieradication rates of quadruple therapy.

Methods

This study included an intention‐to‐treat (ITT) population of 452 subjects who failed first‐line eradication therapy forH. pyloribetween 2003 and 2018. All subjects received a 14‐day course of bismuth‐containing quadruple therapy consisting of esomeprazole (40 mg twice daily), metronidazole (500 mg thrice daily), bismuth subcitrate (120 mg four times daily), and tetracycline (500 mg four times daily). Per‐protocol (PP) analysis of data was performed in subjects who followed up with strict treatment adherence. Eradication was confirmed based on the results of the13C‐urea breath test, rapid urease test (CLOtest®), and histopathologic evaluation. Compliance and adverse effects were also investigated. A minimal inhibitory concentration test was performed on tissue samples obtained from 103 subjects.

Results

The overall eradication rates following ITT and PP analyses were 78.8% (356/452) and 89.5% (314/351), respectively. The annual eradication success rate did not show significant changes (P = .062 [ITT],P = .857 [PP]) over the 15‐year study period. Adverse events were reported in 57.3% of the ITT population. The rates of resistance to metronidazole and tetracycline were 44.7% and 18.4%, respectively.

Conclusions

Despite high antibiotic resistance rates, no significant reduction in annual eradication rates was observed during the study period.
Chronic methyl bromide toxicity is ameliorated by haemodialysis
Authors: Khor Nicole W. M. , Hepburn Kirsten S. , Chiew Angela L. , Somerville Ernest , Micallef Milton , Lee Alexandra T. K. , Endre Zoltán H.
Published: March 2020

Methyl bromide is an odourless, colourless, highly volatile gas, primarily used in fumigation. It can cause significant neurotoxicity, especially with chronic exposure. Haemodialysis has been used in acute toxicity, but its utility in chronic exposure has never been reported. We report the use of haemodialysis in a 20‐year‐old man with chronic methyl bromide toxicity affecting the optic nerves, brain and spinal cord. The patient underwent eight haemodialysis sessions with improvement in plasma bromine concentration, half‐life and marked clinical recovery. The case demonstrates the utility of haemodialysis in the treatment of chronic methyl bromide toxicity.
Crystal structure, bond energy, Raman spectra, and microwave dielectric properties of Ti‐doped Li3Mg2NbO6 ceramics
Authors: Wang Gang , Zhang Dainan , Li Jie , Gan Gongwen , Rao Yiheng , Huang Xin , Yang Yan , Shi Liang , Liao Yulong , Liu Cheng , Jin Lichuan , Zhang Huaiwu
Published: March 2020

Crystal structure exerts dominant influence on the microwave dielectric performance enabling satisfying the demands for 5G communication system. In this study, the Ti‐doped Li3Mg2Nb1‐xTixO6‐x/2 (x = 0.0‐0.1) ceramics were prepared by the solid‐state reaction procedure. Crystal structure refinement and microstructure analysis indicate pure phase with orthorhombic structure and homogeneous microstructure with grain size (~14 μm). The relative permittivity was affected by the relative density, cell volume, and polarizability. The Q × f value was dominated by the Nb‐O bond energy and grain size. The τf value was correlated with the NbO6 octahedral distortion and Nb‐O bond valence. Particularly, the composition (x = 0.04) exhibited remarkable microwave dielectric performance: εr = 15.88, Q × f = 131 000 GHz and τf = −26.8 ppm/°C, providing a promising candidate for millimeter‐wave applications.
Face‐to‐face, blended, flipped, or online learning environment? Impact on learning performance and student cognitions
Authors: Thai Ngoc Thuy Thi , De Wever Bram , Valcke Martin
Published: March 2020

This study compares four learning environments: face‐to‐face learning (F2F), fully e‐learning (EL), blended learning (BL), and flipped classroom (FC) with respect to students' learning performance. Moreover, this present research studies changes in perceived flexibility, intrinsic motivation, self‐efficacy beliefs of students, and the interaction effects in these student variables on learning performance. Two learning environment design elements: (1) lectures (2) group discussions building on guiding questions, were manipulated to create the four learning environments. Third‐year undergraduate students (n = 106), enrolled in the “Animal and Human Physiology” course at CanTho University (Vietnam), were randomly assigned to one of the four learning environments. The results suggest a significant positive differential effect on learning performance when studying in a FC and BL setting. No significant interaction effects could be observed regarding changes in perceived flexibility, intrinsic motivation and self‐efficacy. However, significant differences between learning conditions were observed in perceived flexibility. Analysis of focus group data corroborate the finding that students experience more flexibility in time and place when studying in FC, BL and EL environments. In addition, students in a FC environment reflect significantly larger positive changes in their self‐efficacy. But, the qualitative data show how positive perceptions about flexibility, motivation and self‐efficacy are often cancelled out by negative perceptions.
Radiofrequency or cryoballoon ablation for index pulmonary vein isolation: What is the impact on long‐term clinical outcomes after repeat ablation?
Authors: Inaba Osamu , Metzner Andreas , Rottner Laura , Mathew Shibu , Lemes Christine , Maurer Tilman , Heeger Christian , John Alexander , Hashiguchi Naotaka , Wohlmuth Peter , Ouyang Feifan , Kuck Karl‐Heinz , Rillig Andreas , Reissmann Bruno
Published: March 2020

Aims

The current study sought to assess the impact of the utilized energy source during index ablation on long‐term clinical outcomes after repeat ablation of atrial fibrillation (AF). Index ablation procedures were either performed using radiofrequency current (RFC) (RFC group) or cryoballoon (CB) ablation (CB group). Repeat ablation was performed by the use of RFC.

Methods

A total of 195 patients (138 RFC group; 57 CB group) with paroxysmal AF were included. All patients had a recurrence of AF following the index ablation procedure. Freedom from AF was estimated with the Kaplan‐Meier method.

Results

After a 3 years follow‐up, the estimated arrhythmia‐free survival did not differ between the two groups (RFC group 48% vs CB group 47%, P = .78). During index ablation, procedure times were significantly shorter in the CB group (95 [80, 140] vs 140 [115, 164] minutes, P ≤ .001), whereas fluoroscopy times (16 [11; 22] vs 19 [14; 25] minutes, P = .003), the dose area product (1862 [1203; 2922] vs 3148 [1756; 5888] cGycm2, P ≤ .001) and the amount of contrast dye (92 ± 32 vs 123 ± 33 mL, P ≤ .001) were significantly lower in the RFC group. During repeat ablation, procedure times were significantly shorter in patients being initially treated with RFC (115 [85; 145] vs 125 [105; 150] minutes, P = .007). There was a trend towards a higher pulmonary vein reconnection rate in the RFC group without meeting statistical significance (P = .074).

Conclusions

In patients with repeat ablation of AF, index RFC or CB ablation are equally effective in terms of freedom from AF. Although CB ablation results in shorter index procedures times, durations of repeat ablation are significantly longer.
Dysregulated TFR and TFH cells correlate with B‐cell differentiation and antibody production in autoimmune hepatitis
Authors: Liang Ma , Liwen Zhang , Juan Dai , Yun Zhuang , Yanbo Ding , Jianping Chen
Published: March 2020

Follicular helper T (TFH) cell provides germinal centre (GC) B cell with critical signals for autoantibody production in the immunopathogenesis and progression of autoimmune hepatitis (AIH). However, the immunoregulatory functions of follicular regulatory T (TFR) cell in AIH are still unclear. The numbers of circulating TFR/TFH cells were measured in AIH patients. Moreover, we established experimental autoimmune hepatitis (EAH) model to examine the function of TFR cells on B‐cell differentiation and autoantibody production in vivo and vitro. AIH patients had significantly increased numbers of TFH cells and decreased numbers of TFR cells as well as imbalanced TFR/TFH‐type cytokines (IL‐10, TGF‐β1 and IL‐21) compared with healthy controls (HCs). In addition, TFR cell numbers negatively correlated with TFH cell numbers. Also, serum hypergammaglobulinaemia (IgG and IgM) concentration negatively correlated the levels of serum IL‐21, but positively correlated with the levels of serum IL‐10 in AIH patients. Furthermore, in comparison with control group, significantly higher frequencies of spleen TFR cells but lower frequencies of spleen TFH cells were detected in the EAH group. Further analysis found that TFR cells simultaneously express the phenotypic characteristics of Treg and TFH cells, but exercise as negative regulators of autoantibody production in vitro culture. Our findings demonstrated that dysregulated between TFR and TFH cells might cause excessive production of autoantibodies and destruction of the immune homeostasis, leading to the immunopathological process in AIH.
The light at the end of the tunnel gets vivid for spinal muscular atrophy
Authors: Dutta Debashis , Chandra Goutam , Mohanakumar Kochupurackal P.
Published: March 2020

Kessler et al. in this current issue have attempted to discern biomarker(s) for spinal muscular atrophy (SMA) by assessing alterations in cerebrospinal fluid (CSF) proteomics profile. Recently, antisense oligonucleotide (nusinersen) therapy is shown to mitigate pathologies and provide behavioral improvements in patients. This Editorial highlights the study by Kessler et al on the proteomics of CSF from adult and young patients prior to, and 10 months after nusinersen intrathecal therapy. Although the study by Kessler et al. suffers from small sample size and mixed results that deterred a strong conclusion, yet is a strong case‒control study that is contemporary and important to the patients, clinicians and care‐takers alike. Since identifying biomarker and characterizing the pathology in SMA are imminent necessity to advance this promising therapy, the high‐throughput CSF proteomics data prior and after nusinersen therapy provide possible biomarkers that may help in identification of positive responders, the disease course, efficacy of treatment, and more accurate prognosis.

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