bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of circulating zonulin as a potential marker in the pathogenesis of nonalcoholic fatty liver disease
Authors: Hendy Olfat M. , Elsabaawy Maha M. , Aref Mona M. , Khalaf Fatma M. , Oda Abdel Moaty A. , El Shazly Helmy M.
Published: April 2017

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of liver disorders ranging from simple hepatic steatosis up to nonalcoholic steatohepatitis (NASH) evolving to cirrhosis and hepatocellular carcinoma (HCC). Liver biopsy is still the gold standard modality for diagnosing and staging NAFLD. The linkage between intestinal microbiota and NAFLD, might suggest a potential role of serum zonulin in NAFLD diagnosis. To appraise the role of circulating zonulin in NAFLD pathogenesis, 56 subjects with proved NAFLD by ultrasonography and liver biopsy, as well as 20 healthy controls were tested. Liver function tests, serum glucose, fasting insulin, C peptide, lipid profile, homeostasis model assessment of insulin resistance (HOMA‐IR), IL‐6, and circulating zonulin were performed to all subjects. Aspartate transaminase (AST), alanine transaminase (ALT), gamma‐glutamyl transferase (GGT), triglycerides, HDL‐c, fasting insulin, C peptide, HOMA‐IR, IL‐6, and serum zonulin were higher in NAFLD group than in controls (p < 0.05), and in NASH patients than those with simple steatosis (p < 0.05). Zonulin was positively correlated with body mass index (BMI), ALT, triglycerides, fasting insulin, HOMA‐IR, liver histopathology, and serum IL‐6 (p < 0.05), with inverse correlation to HDL‐C (p < 0.05). At cut off 8.3 pc/mL, serum zonulin was found to be of diagnostic value of NASH occurrence with 100% sensitivity and specificity (AUR = 1.000, p‐value = <0.001). The increasing zonulin levels in NAFLD patients with steep rise in NASH group denotes a possible role in pathogenesis of NAFLD occurrence and progression. This could open a new avenue of implicating zonulin antagonists as targeted therapies in NAFLD prevention.
A five‐miRNA expression signature predicts survival in hepatocellular carcinoma
Authors: Liu Gang , Wang Hui , Fu Jin‐dong , Liu Jing‐ying , Yan Ai‐guo , Guan Yan‐yan
Published: April 2017

The aim of this study was to identify a microRNA (miRNA) expression signature for predicting HCC (hepatocellular carcinoma) survival. A total of 322 HCC patients in The Cancer Genome Atlas (TCGA) database were randomly divided into training and testing set. miRNAs, associated with survival time in the training set, were identified by using univariate Cox regression analysis. The risk score was formulated based on the expression levels of these miRNAs. Then the miRNA signature was validated in testing set through Kaplan–Meier analysis and log‐rank test. hsa‐miR‐301a, hsa‐miR‐132, hsa‐miR‐212, hsa‐miR‐489, and hsa‐miR‐1468 were identified to formulate risk score in training set and used to calculate the risk score of each patients in testing set. About 161 patients in testing set were segregated into high‐ and low‐risk group according to the median risk score. The survival time of high‐risk group was significantly shorter (p = 0.0248) than low‐risk group in testing test. The target genes of five miRNAs were significantly enriched in valine, leucine, and isoleucine degradation pathway and PPAR signaling pathway. hsa‐miR‐1468 had an up‐regulated tendency in HCC tissues compared to adjacent tumor tissues. The expression of hsa‐miR‐301a, hsa‐miR‐132, hsa‐miR‐212, hsa‐miR‐489, and hsa‐miR‐1468, which might be potential biomarkers to evaluate HCC patients' prognosis.
A thirst for development: mapping water stress using night‐time stable lights as predictors of province‐level water stress in China
Authors: You Xiaojun , Monahan Kyle M
Published: April 2017

Given the rapid development within China, the inequality of available water resources has been increasingly of interest. Current methods for assessing water stress are inadequate for province‐scale rapid monitoring. A more responsive indicator at a finer scale is needed to understand the distribution of water stress in China. This paper selected Defense Meteorological Satellite Program Operational Line‐scan System night‐time stable lights as a proxy for water stress at the province level in China from 2004 to 2012, as night‐time lights are closely linked with population density, electricity consumption and other social, economic and environmental indicators associated with water stress. The linear regression results showed the intensity of night‐time lights can serve as a predictive tool to assess water stress across provinces with an R2 from 0.797 to 0.854. The model worked especially well in some regions, such as East China, North China and South West China. Nonetheless, confounding factors interfered with the predictive relationship, including population density, level of economic development, natural resource endowment and industrial structures, etc. The model was not greatly improved by building a multi‐variable linear regression including agricultural and industrial indicators. A straightforward predictor of water stress using remotely sensed data was developed.
Effects of Aluminium on Long‐Term Memory in Rats and on SIRT1 Mediating the Transcription of CREB‐Dependent Gene in Hippocampus
Authors: Yan Dongying , Jin Cuihong , Cao Yang , Wang Lulu , Lu Xiaobo , Yang Jinghua , Wu Shengwen , Cai Yuan
Published: April 2017

Epidemiological investigations have shown that aluminium (Al) is an important neurotoxicant which can be absorbed by organisms via various routes. Previous studies have confirmed that exposure to Al could cause neurodegenerative diseases, decline CREB phosphorylation and then down‐regulate the transcription and protein expression of its target genes including BDNF. However, recent studies revealed that CREB activation alone was far from enough to activate the expression of long‐term memory (LTM)‐related genes; there might be other regulatory factors involved in this process. Several studies showed that TORC1 might be involved in regulating the transcription of downstream target genes as well. Also, TORC1 could be mediated by SIRT1 during the formation of LTM. However, the role of CREB regulating system in Al‐induced LTM impairment was still not utterly elucidated till now. This study was designed to establish the rat model of subchronic Al exposure to observe the neuroethology, regulatory factor levels and molecular biological alterations in hippocampal cells. The results showed that, with the increasing AlCl3 dose, blood Al content increased gradually; morphology of the hippocampus and neuronal ultrastructure were aberrant; in the Morris water maze test, the escape latency and distance travelled became longer, swimming traces turned more complicated in the place navigation test; intracellular Ca2+, cAMP levels declined significantly in AlCl3‐treated rats, followed by abated nuclear translocation of TORC1 and decreased SIRT1, TORC1 and pCREB levels. These results indicate that SIRT1 and TORC1 might play an important mediating role in Al‐induced LTM impairment.
Pedagogical, social and technical designs of a blended synchronous learning environment
Authors: Wang Qiyun , Huang Changqin
Published: April 2017

In this study, a blended synchronous learning environment (BSLE) was designed from pedagogical, social and technical perspectives. It was created for a group of master's students to attend lessons in the classroom and at the same time allow a few of them to join the identical sessions using video conferencing from different sites. The purpose of the study was to describe the guiding principles for pedagogical, social and technical designs and specific strategies applied, and identify the students' learning experiences and perceptions of the environment. Results showed that the BSLE could extend certain features of classroom instruction to the online students and they had equivalent learning experiences. They also liked the flexibility and convenience of attending lessons via video conferencing. This study further found that smooth and clear audio communication, redesign of certain learning activities and the quality of audio were crucial for the BSLE to be useful in practice.
Impacts of taxonomic inertia for the conservation ofAfrican ungulate diversity: an overview
Authors: Gippoliti Spartaco , Cotterill Fenton P. D. , Zinner Dietmar , Groves Colin P.
Published: April 2017

ABSTRACT

We review the state of African ungulate taxonomy over the last 120 years, with an emphasis on the introduction of the polytypic species concept and the discipline's general neglect since the middle of the 20th century. We single out negative consequences of ‘orthodox’ taxonomy, highlighting numerous cases of neglect of threatened lineages, unsound translocations that led to lineage introgression, and cases of maladaptation to local conditions including parasitic infections. Additionally, several captive breeding programmes have been hampered by chromosome rearrangements caused by involuntary lineage mixing. We advocate that specimen‐based taxonomy should regain its keystone role in mammal research and conservation biology, with its scientific values augmented with genomic evidence. While integration with molecular biology, ecology and behaviour is needed for a full understanding of ungulate alpha diversity, we stress that morphological diversity has been neglected despite its tremendous practical importance for some groups of ‘utilizers’ such as trophy hunters, wildlife tourists and conservationists. We conclude that there is no evidence that purported ‘taxonomic inflation’ has adverse effects on ungulate conservation: rather, it is taxonomic inertia that has such adverse effects. We stress that sound science, founded on robust taxonomy, should underpin effective sustainable management (hunting, ranching, captive breeding and reintroduction programmes) of this unique African natural resource.
α‐Mangostin decreases β‐amyloid peptides production via modulation of amyloidogenic pathway
Authors: Zhao Lan‐Xue , Wang Yan , Liu Ting , Wang Yan‐Xia , Chen Hong‐Zhuan , Xu Jian‐Rong , Qiu Yu
Published: April 2017

Aims

β‐amyloid (Aβ) aggregation and deposition play a central role in the pathogenic process of Alzheimer's disease (AD). α‐Mangostin (α‐M), a polyphenolic xanthone, have been shown to dissociate Aβ oligomers. In this study, we further investigated the effect of α‐M on Aβ production and its molecular mechanism.

Methods

The Aβ and soluble amyloid precursor protein α (sAPPα) in culture medium of cortical neurons were measured by ELISA. The activities of α‐, β‐, and γ‐secretases were assayed, and the interaction between α‐M and β‐ or γ‐secretases was simulated by molecular docking.

Results

α‐M significantly decreased Aβ40 and Aβ42 production. α‐M did not affect the expression of enzymes involved in nonamyloidogenic and amyloidogenic pathways, but significantly decreased the activities of β‐secretase and likely γ‐secretase with IC50 13.22 nmol·L−1 and 16.98 nmol·L−1, respectively. Molecular docking demonstrated that α‐M interacted with β‐site amyloid precursor protein cleaving enzyme 1 and presenilin 1 to interfere with their active sites.

Conclusions

Our data demonstrate that α‐M decreases Aβ production through inhibiting activities of β‐secretase and likely γ‐secretase in the amyloidogenic pathway. The current data together with previous study indicated that α‐M could be a novel neuroprotective agent through intervention of multiple pathological processes of AD.
Expanding access to naloxone for family members: The Massachusetts experience
Authors: Bagley Sarah M. , Forman Leah S. , Ruiz Sarah , Cranston Kevin , Walley Alexander Y.
Published: April 2017

Introduction and Aims

The Massachusetts Department of Public Health Overdose Education and Naloxone Distribution Program provides overdose education and naloxone rescue kits to people at risk for overdose and bystanders, including family members. Using Massachusetts Department of Public Health data, the aims are to: (i) describe characteristics of family members who receive naloxone; (ii) identify where family members obtain naloxone; and (iii) describe characteristics of rescues by family members.

Design and Methods

We conducted a retrospective review using program enrollee information collected on a standardised form between 2008 and 2015. We calculated descriptive statistics, including demographics, current substance use, enrolment location, history of witnessed overdoses and rescue attempt characteristics. We conducted a stratified analysis comparing family members who used drugs with those who did not.

Results

Family members were 27% of total program enrollees (n = 10 883/40 801). Family members who reported substance use (n = 4679) were 35.6 years (mean), 50.6% female, 76.3% non‐Hispanic white, 75.6% had witnessed an overdose, and they obtained naloxone most frequently at HIV prevention programs. Family members who did not report substance use (n = 6148) were 49.2 years (mean), 73.8% female, 87.9% non‐Hispanic white, 35.3% had witnessed an overdose, and they obtained naloxone most frequently at community meetings. Family members were responsible for 20% (n = 860/4373) of the total rescue attempts.

Discussion and Conclusions

The Massachusetts experience demonstrates that family members can be active participants in responding to the overdose epidemic by rescuing family members and others. Targeted intervention strategies for families should be included in efforts to expand overdose education and naloxone in Massachusetts.
HIV/AIDS and other household shocks as catalysts of local commercialization of non‐timber forest products in Southern Africa
Authors: Weyer D. , Shackleton C. M. , Adam Y. O.
Published: April 2017

Local trade in non‐timber forest products (NTFPs) is increasing globally, yet the causes have been little studied. We examine household shock as a driver of NTFP trade in five southern African countries, with an emphasis on HIV/AIDS‐related illness and death. Over the past two years, 95% of trader households experienced at least one shock, with family illness and death recorded for 68% and 42% of households, respectively. Almost 40% had entered the trade because of HIV/AIDS‐related shocks. Additional shocks included natural disasters, crop pests or failure and livestock loss. The sale of NTFPs was the third most common coping strategy, after kinship and agricultural adjustments. Coping strategies differed between sites and type of shock.
Impacts of grazing intensity and increased precipitation on a grasshopper assemblage (Orthoptera: Acrididae) in a meadow steppe
Authors: ZHU HUI , QU YEKUAN , ZHANG DUO , LI JUNJIAN , WEN MING , WANG DELI , REN BINGZHONG
Published: April 2017

1. Grasshoppers are dominant herbivores in grassland ecosystems, and many studies have examined how grazing by large herbivores and precipitation patterns individually influence the dynamics of grassland grasshopper assemblages, but their combined effects are largely unknown.

2. In this study, grazing intensities (ungrazed, moderate, and heavy) were manipulated and precipitation (ambient and increased amount of rainfall) altered in a field experiment to test the effects of grazing and altered precipitation on a grasshopper community in a meadow steppe in northeastern China.

3. It was found that grasshopper species richness did not change according to different grazing intensities under ambient precipitation, but was significantly higher (by 38.1%) in moderate grazing intensities under increased precipitation. Grasshopper abundance increased considerably with increasing grazing intensities in ambient precipitation treatments; however, grasshopper abundance in heavy grazing intensities was significantly lower (by 32.9%) than in the other two grazing intensities under increased precipitation. Moreover, the responses of grasshopper abundance to grazing under altered precipitation were species‐specific.

4. Grazing effects on grasshopper species diversity were mediated through the species richness and biomass of grasses (food resources), but the effects on grasshopper abundance were mediated through plant height (vegetation structure) under altered precipitation.

5. These results suggest that appropriate grazing by large herbivores would be considered as beneficial management practices for maintaining grasshopper diversity and abundance under conditions of increased precipitation in grassland ecosystems. Additionally, greater attention should be paid to the population dynamics of different grasshopper species to better understand the responses of grasslands to grazing and altered precipitation.
Oviposition preference and offspring performance in container breeding mosquitoes: evaluating the effects of organic compounds and laboratory colonisation
Authors: ALLGOOD DAVID W. , YEE DONALD A.
Published: April 2017

1. The preference–performance hypothesis (PPH) predicts that organisms lacking parental care should oviposit in habitats that optimise offspring performance. Preference–performance relationships were investigated for theAsian tiger mosquito (Aedes albopictusSkuse) and the southern house mosquito (Culex quinquefasciatusSay) (Diptera:Culicidae), two medically important container‐breeding species, in response to an organic chemical blend mimicking decaying plant matter. Additionally, the effects of long‐term laboratory colonisation ofCx. quinquefasciatususing wild and laboratory strains were evaluated.

2. Oviposition bioassays were conducted by releasing gravid mosquitoes into field enclosures with automobile tires containing low and high concentrations of the chemical blend, and water controls. The offspring were then reared in water collected from the tires in which they were deposited.

3.Aedes albopictusand wildCx. quinquefasciatuslaid more eggs in the chemical blend than water controls but did not differentiate between the low and high concentrations. Conversely, laboratoryCx. quinquefasciatusonly preferred the high concentration to the low concentration. No statistical associations between oviposition preference and larval survival were found, as the chemical blend did not affect survivorship of either species.

4. The oviposition preference for the chemical blend over water controls suggests that both species oviposit in the best available resource environment, but further studies are needed before conclusions regarding preference–performance relationships can be drawn.

5. It was found that long‐term laboratory colonisation affects the oviposition behaviour inCx. quinquefasciatus, suggesting that behavioural studies on laboratory strains are not always applicable to wild populations.
Working whilst studying in higher education: The impact of the economic crisis on academic and labour market success
Authors: Sanchez‐Gelabert Albert , Figueroa Mijail , Elias Marina
Published: April 2017

An analysis of the phenomenon of combining work and study amongst university students is made using data obtained from surveys of graduates carried out four years after finishing their degrees. First, the article reviews the evolution of the phenomenon over the last ten years, taking into account the Catalan University Quality Assurance Agency (AQU) labour market insertion surveys for 2005, 2008, 2011 and 2014. Second, the 2008 and 2014 waves are compared to analyse the impact of the economic crisis. In this case, how combining work and study affects academic results and labour market insertion is studied, in addition to whether or not differences occur according to the family's educational background. A random stratified two‐stage sampling is used to obtain the results; descriptive and ANOVA analyses with different factors are performed. The evolution shows how the numbers of students who combine work and study has increased, especially among those whose parents have little education. Furthermore, this means that lower marks are obtained and that there is a greater degree of inequality in labour market insertion, depending on the educational background of the family of origin. In general, the relationship between the different variables shows how combining work and study has negative effects on marks but positive effects on labour market insertion, especially if the work experience whilst at university is related to the studies.
Transcriptional mechanisms underlying life‐history responses to climate change in the three‐spined stickleback
Authors: Kim Sin‐Yeon , Costa Maria M. , Esteve‐Codina Anna , Velando Alberto
Published: April 2017

Phenotypic plasticity, the ability of an organism to express different phenotypes depending on the environment, provides an important mechanism by which an animal population can persist under rapid climate change. We experimentally tested both life‐history and transcriptional responses of an ecological model species, the three‐spined stickleback, to warm acclimation at the southern edge of its European range. We explored cross‐environment genetic correlations of key life‐history traits in male sticklebacks exposed to long‐term temperature changes to examine whether the plasticity pattern was variable among genotypes by using a character‐state approach. We also studied gene expression plasticity by analysing both whole‐transcriptome and candidate gene expression in brain and liver. Male sticklebacks that developed under warmer conditions during winter were smaller in size and invested less in nuptial coloration at the beginning of the breeding season, showing similar responses across different genotypes. The lack of genetic variation in life‐history responses may limit any future evolution of the thermal reaction norm in the study population. After long‐term exposure to increased winter temperatures, genes responsible for several metabolic and oxidation–reduction processes were upregulated, and some hormone genes involved in growth and reproduction were downregulated in the brain. In the liver, there was no significantly represented gene ontology by the differentially expressed genes. Since a higher temperature leads to a higher resting metabolic rate, living in warmer environments may incur higher energetic costs for ectotherms to maintain cellular homoeostasis, resulting in negative consequences for life‐history traits. The expression of genes related to metabolism, cellular homoeostasis and regulatory signalling may underlie temperature‐induced changes in life history.
Lights, Camera, Activism: Using a Film Series to Generate Feminist Dialogue About Campus Sexual Violence
Authors: Purcell John B. K. , Oldham C. Rebecca , Weiser Dana A. , Sharp Elizabeth A.
Published: April 2017

We examine the use of an interdisciplinary film series, “2015 Sexism | Cinema: 50 Years on the Silver Screen,” as a space for discussion where attendees can discover allies, express critical thought, and advance their thinking. A film series is a useful response to the widespread problem of campus sexual assault in three critical ways: (a) a theater provides an informal, recreational space for discussion of feminist thought; (b) the content of the films highlights the insidious nature of sexual violence and gender inequality in our culture; and (c) there exists a degree of separation that subverts defensiveness while inspiring a critical dialogue. We discuss the utility of a film series as an accessible approach to the cultural antecedents of sexual violence on college campuses. We offer our own experiences of the film series and recommend film as a feminist pedagogical tool to address sexual violence.
Feminist Agency, Sexual Scripts, and Sexual Violence: Developing a Model for Postgendered Family Communication
Authors: Rossetto Kelly R. , Tollison Andrew C.
Published: April 2017

We explore the interrelated research on intersectionality, feminist agency, script theory, and gender socialization to uncover the ways in which college students may experience institutionalized sexual scripts and perceptions of agency in sexual encounters. We theorize that changes at the family level could ultimately help create a shift in a campus culture that has become entrenched, with biased sexual scripts that lead to power imbalances and sexual violence. With underpinnings of social role theory and modeling, this article develops a model of postgendered family communication. Practical family communication suggestions based on the model are provided for parents and family educators that could help shift sexual scripts, enable feminist agency, and improve rates of sexual assault incidence and reporting at the institutional level.
Peridynamics for predicting damage and its growth in composites
Authors: Hu Y. , Madenci E. , Phan N.
Published: April 2017

This study concerns progressive damage analysis of composite laminates by using peridynamics. It is not limited to any fibre orientation and laminate layup. Its validity is established by comparing against the recent data generated by the Air Force Research Laboratory under the Tech Scout Project. The model simulations predict the stiffness, strength and damage progression in each ply for three different laminate layups with a circular hole under tensile/compressive loading. These predictions compare well with the experimental observations and measurements for each laminate layup.
Do Private Utilities Outperform Local Government-Owned Utilities? Evidence from German Retail Electricity
Authors: Stiel Caroline , Cullmann Astrid , Nieswand Maria
Published: April 2017

Against the background of remunicipalisation trends in European public service sectors, this paper estimates firm-level productivity for German electricity retailers and tests whether the ownership type has a significant impact on productivity. We specify a production function for the retail sector with labour and external services as main inputs, which is estimated using a control function approach. Employing a newly constructed dataset on German utilities by the German Federal Statistical Office for the years 2003-12, we find that firm-level productivity generally increased until 2008 but not afterwards. We do not find any evidence for ownership having an impact on productivity.
A systematic review of ultrasound imaging as a tool for evaluating haemophilic arthropathy in children and adults
Authors: Ligocki C. C. , Abadeh A. , Wang K. C. , Adams‐Webber T. , Blanchette V. S. , Doria A. S.
Published: April 2017

The purpose of this study was to semi‐quantitatively assess the evidence on the value of ultrasound (US) for assessment of haemophilic arthropathy (HA) in children and adults based on the following questions: (1) Does early diagnosis of pathological findings, using available US techniques, impact the functional status of the joint? (2) Do current available US techniques have the ability to accurately detect pathological changes in target joints in haemophilic patients? (3) Does treatment (prophylaxis) improve US evidence of haemophilic arthropathy in children and adults? (4) Is there any association between various US scoring systems and other clinical/radiological constructs? Of the 6880 citations identified searching databases such as MEDLINE, Embase, CENTRAL and Web of Science, 20 articles investigating either the diagnostic accuracy of US and/or US scanning protocols and scoring systems for assessment of HA met the inclusion criteria for the study. Of these, 14 articles evaluating the diagnostic accuracy of US were assessed by two independent reviewers for reporting quality using the Standards for Reporting of Diagnostic Accuracy (STARD) tool and for methodological quality using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS‐2) tool. Using STARD, 1/14 studies (7%) was scored as of high reporting quality and 8/14 (57%), of moderate quality. Assessment with QUADAS‐2 reported 2/14 (14%) studies as having high methodological quality and 6/14 (43%) as having moderate quality. There is fair evidence (Grade B) to recommend US as an accurate technique for early diagnosis of HA, to demonstrate that US scores correlate with clinical/US constructs and to prove an association between US findings and functional status of the joint. However, there is insufficient evidence (Grade I) to conclude that US‐detectable findings in HA are sensitive to changes in therapy.
Patients’ experiences of consultations with physician associates in primary care in England: A qualitative study
Authors: Halter Mary , Drennan Vari M. , Joly Louise M. , Gabe Jonathan , Gage Heather , de Lusignan Simon
Published: April 2017

Background

Physician associates are new to English general practice and set to expand in numbers.

Objective

To investigate the patients’ perspective on consulting with physician associates in general practice.

Design

A qualitative study, using semi‐structured interviews, with thematic analysis.

Setting and participants

Thirty volunteer patients of 430 who had consulted physician associates for a same‐day appointment and had returned a satisfaction survey, in six general practices employing physician associates in England.

Findings

Some participants only consulted once with a physician associate and others more frequently. The conditions consulted for ranged from minor illnesses to those requiring immediate hospital admission. Understanding the role of the physician associate varied from ‘certain and correct’ to ‘uncertain’, to ‘certain and incorrect’, where the patient believed the physician associate to be a doctor. Most, but not all, reported positive experiences and outcomes of their consultation, with some choosing to consult the physician. Those with negative experiences described problems when the limits of the role were reached, requiring additional GP consultations or prescription delay. Trust and confidence in the physician associate was derived from trust in the NHS, the general practice and the individual physician associate. Willingness to consult a physician associate was contingent on the patient's assessment of the severity or complexity of the problem and the desire for provider continuity.

Conclusion

Patients saw physician associates as an appropriate general practitioner substitute. Patients’ experience could inform delivery redesign.
Concentration threshold effect on properties of zinc‐doped lithium niobate crystals
Authors: Palatnikov Mikhail N. , Sidorov Nikolay V. , Makarova Olga V. , Manukovskaya Diana V. , Aleshina Ludmila A. , Kadetova Alexandra V.
Published: April 2017

Results of LiNbO3:Zn researches often diverge because sharp changes in physicochemical characteristics of the system melt‐crystal that occur at doping are usually not taken into consideration. When a series of doped crystals is grown Zn is usually added to the melt with step 1.5‐2 mol%. This obstructs detection of exact threshold concentration. We have grown LiNbO3:Zn crystals doped by 4.0÷9.0 mol% ZnO with step ~1 mol%. Around the dopant, threshold concentration step was narrowed to ~0.1 mol%. We have researched physicochemical properties of the system melt‐crystal and structure evolution by Raman spectroscopy and full‐profile analysis of XRD. We have detected exact threshold concentration for LiNbO3:Zn and concluded that crystals doped by prethreshold concentrations of ZnO are the best for most applications because of the higher optical homogeneity.
Parental Education and Expensive Consumption Habits
Authors: Zwarthoed Danielle
Published: April 2017

The aim of this article is to investigate the general and special obligations of parents with respect to the shaping of consumption habits, from a liberal egalitarian perspective. The article argues that, in virtue of them being well placed to shape the next generation's consumption habits, parents have a duty of justice to prevent their children from developing expensive consumption habits in order to enable them to leave their fair share to others. In virtue of the special relationship they have with their children, parents have a duty of care, and this may also require parents to prevent their children from developing expensive consumption habits. Then the article discusses whether and under which conditions these duties hold in unjust circumstances, where a consumerist ethos is predominant and where other parents and educational agents do not collaborate effectively.
Atrial fibrillation patients with isolated pulmonary veins: Is sinus rhythm achievable?
Authors: Szilágyi Judit , Marcus Gregory M. , Badhwar Nitish , Lee Byron K. , Lee Randall J. , Vedantham Vasanth , Tseng Zian H. , Walters Tomos , Scheinman Melvin , Olgin Jeffrey , Gerstenfeld Edward P.
Published: April 2017

Background

The cornerstone of atrial fibrillation (AF) ablation is isolation of the pulmonary veins (PVs). Patients with recurrent AF undergoing repeat ablation usually have PV reconnection (PVr). The ablation strategy and outcome of patients undergoing repeat ablation who have persistent isolation of all PVs (PVi) at the time of repeat ablation is unknown.

Methods and results

We studied consecutive patients with recurrent AF undergoing repeat ablation and compared patients with PVi to those with PVr. One hundred fifty‐two patients underwent repeat ablation, and of these, 25 patients (16.4%) had PVi. Patients with PVi underwent ablation targeting any isoproterenol induced AF triggers, atrial substrate, or inducible atrial tachycardias or flutters. Patients with PVi compared to PVr were more likely to have a history of persistent AF (64% vs. 26%; P < 0.0001), obesity (BMI 30.4 vs. 28.2; P = 0.05), and prior use of contact force sensing catheters (28% vs. 0.8%, P < 0.0001). After a mean follow‐up of 19 ± 15 months, 56% of PVi patients remained in sinus rhythm compared to 76.3% of PVr patients (P = 0.036). In a multivariable model, PVi patients and those with cardiomyopathy had a higher risk of recurrent atrial tachyarrhythmias (HR = 3.6 95%, CI 1.6–8.3, P = 0.002 and HR = 6.2, 95% CI 2.3–16.3, P < 0.0001, respectively).

Conclusion

In patients who have all PVs isolated at the time of the redo AF ablation, a strategy of targeting non‐PV AF triggers and inducible flutters can still lead to AF freedom in more than half of patients. Patients with PVr, however, have a better long‐term outcome.
Preliminary findings on the safety of 1.5 and 3 Tesla magnetic resonance imaging in cardiac pacemaker patients
Authors: van Dijk Vincent F. , Delnoy Peter Paul H.M. , Smit Jaap Jan J. , Ramdat Misier R. Anand , Elvan Arif , van Es H. Wouter , Rensing Benno J.W.M. , Raciti Giovanni , Boersma Lucas V.A.
Published: April 2017

Introduction

Modern pacemakers are designed to allow patients to undergo magnetic resonance imaging (MRI) under a set of specific conditions. Aim of this study is to provide confirmatory evidence of safety and performance of a new pacing system (ImageReady™, Boston Scientific) in patients undergoing 1.5 and 3T MRI.

Methods and results

Two prospective, nonrandomized, single‐arm studies were designed to provide confirmatory data of no impact of MRI on device function, lead parameters, and patient conditions in subjects implanted with the system undergoing a clinically non‐indicated 1.5T and 3T MRI, respectively. Device measurements were done within 1 hour before and after the scan and at 1 month follow‐up. Thirty‐two subjects underwent MRI visit (17 subjects with 1.5T MRI and 15 subjects with 3T MRI). There were no unanticipated adverse effects related to the pacemaker. Device measurements taken pre‐ and post‐MRI scan did not show any clinical relevant change that could indicate an effect of the MRI on the device or at the lead‐tissue interface (RV threshold change: 0.01 ± 0.13 V, P = 0.60; RA threshold change: 0.01 ± 0.11 V, P = 0.53; R wave change: −0.44 ± 1.73 mV, P = 0.36; R wave change: 0.12 ± 1.67 mV, P = 0.73), with data confirmed at 1‐month follow‐up visit.

Conclusion

The study documented safety of the pacing system in the 1.5T and 3T MRI environment by showing no adverse events related to device or MRI scan. Additional data are required to cover the more complex scenarios involving different diagnostic needs, conditions of use, clinical conditions, and new emerging technologies.
Use of adenosine to shorten the post ablation waiting period for cavotricuspid isthmus‐dependent atrial flutter
Authors: Morales Gustavo , Darrat Yousef H. , Lellouche Nicolas , Kim Sun Moon , Butt Muhammad , Bidwell Katrina , Lippert William , Ogunbayo Gbolahan , Hamon David , Di Biase Luigi , Natale Andrea , Parrott Kevin , Elayi Claude S
Published: April 2017

Background

Dormant conduction unmasked by adenosine predicts clinical recurrences of cavotricuspid isthmus (CTI) dependent atrial flutter following catheter ablation. Conventional practice involves a waiting period of 20 to 30 minutes after achievement of a bidirectional line of block (BDB) to monitor for recovery of conduction.

Objective

Assess whether abolition of dormant conduction with adenosine immediately after CTI ablation and BDB can predict the lack of CTI conduction recovery during the following 30 minutes.

Methods

Consecutive patients undergoing catheter ablation for CTI‐dependent atrial flutter were studied. Following the completion of CTI ablation and documentation of BDB, adenosine (≥12 mg IV) was administered immediately. In cases of dormant conduction, the CTI was ablated again until its abolition. After the achievement of BDB without dormant conduction, spontaneous CTI reconnection during the following 30 minutes and dormant conduction with adenosine at 30 minutes were evaluated.

Results

A CTI block was achieved in 171 patients. Nine patients (5.3%) had dormant conduction across the CTI immediately after ablation and BDB, and required further ablation. Two patients (1.2%) had subsequent spontaneous time‐dependent reconnection within 30 minutes. Two other patients (1.2%) developed late dormant conduction with adenosine at 30 minutes. All 4 patients underwent further ablation.

Conclusion

A negative adenosine challenge immediately after CTI ablation with bidirectional block, or after abolition of dormant conduction with further ablation, strongly predicted the absence of subsequent spontaneous reconnection within 30 minutes. Based on these results, the conventional waiting period is unnecessary in 97.6% patients without dormant conduction after CTI‐dependent flutter ablation.
Impaired left atrial function predicts inappropriate shocks in primary prevention implantable cardioverter‐defibrillator candidates
Authors: Tao Susumu , Ashikaga Hiroshi , Ciuffo Luisa A. , Yoneyama Kihei , Lima Joao A.C. , Frank Terry F. , Weiss Robert G. , Tomaselli Gordon F. , Wu Katherine C.
Published: April 2017

Introduction

Inappropriate implantable cardioverter‐defibrillator (ICD) shocks, commonly caused by atrial fibrillation (AF), are associated with an increased mortality. Because impaired left atrial (LA) function predicts development of AF, we hypothesized that impaired LA function predicts inappropriate shocks beyond a history of AF.

Methods and results

We prospectively analyzed the association between LA function and incident inappropriate shocks in primary prevention ICD candidates. In the Prospective Observational Study of ICD (PROSE‐ICD), we assessed LA function using tissue‐tracking cardiac magnetic resonance (CMR) prior to ICD implantation. A total of 162 patients (113 males, age 56 ± 15 years) were included. During the mean follow‐up of 4.0 ± 2.9 years, 26 patients (16%) experienced inappropriate shocks due to AF (n = 19; 73%), supraventricular tachycardia (n = 5; 19%), and abnormal sensing (n = 2; 8%). In univariable analyses, inappropriate shocks were associated with AF history prior to ICD implantation, age below 70 years, QRS duration less than 120 milliseconds, larger LA minimum volume, lower LA stroke volume, lower LA emptying fraction, impaired LA maximum and preatrial contraction strains (Smax and SpreA), and impaired LA strain rate during left ventricular systole and atrial contraction (SRs and SRa). In multivariable analysis, impaired Smax (hazard ratio [HR]: 0.96, P = 0.044), SpreA (HR: 0.94, P = 0.030), and SRa (HR: 0.25, P < 0.001) were independently associated with inappropriate shocks. The receiver‐operating characteristics curve showed that SRa improved the predictive value beyond the patient demographics including AF history (P = 0.033).

Conclusion

Impaired LA function assessed by tissue‐tracking CMR is an independent predictor of inappropriate shocks in primary prevention ICD candidates beyond AF history.
Association of obstructive sleep apnea with arterial stiffness and nondipping blood pressure in patients with hypertension
Authors: Jenner Raimundo , Fatureto‐Borges Fernanda , Costa‐Hong Valéria , Lopes Heno F. , Teixeira Sandra H. , Marum Elias , Giorgi Dante A. M. , Consolim‐Colombo Fernanda M. , Bortolotto Luiz A. , Lorenzi‐Filho Geraldo , Krieger Eduardo M. , Drager Luciano F.
Published: April 2017

Whether sex influences the association of obstructive sleep apnea (OSA) with markers of cardiovascular risk in patients with hypertension is unknown. In this study, 95 hypertensive participants underwent carotid‐femoral pulse wave velocity, 24‐hour ambulatory blood pressure monitoring, echocardiogram, and polysomnography after a 30‐day standardized treatment with hydrochlorothiazide plus enalapril or losartan. OSA was present in 52 patients. Compared with non‐OSA patients, pulse wave velocity values were higher in the OSA group (men: 11.1±2.2 vs 12.7±2.4 m/s, P=.04; women: 11.8±2.4 vs 13.2±2.2 m/s, P=.03). The proportion of diastolic dysfunction was significant in men and women with OSA. Compared with non‐OSA patients, nondipping systolic blood pressure in OSA was higher in men (14.3% vs 46.4%) and in women (41.4% vs 65.2%). OSA was independently associated with pulse wave velocity (β=1.050; P=.025) and nondipping systolic blood pressure (odds ratio, 3.03; 95% confidence interval, 1.08–8.55; P=.035) in the regression analysis. In conclusion, OSA is independently associated with arterial stiffness and nondipping blood pressure in patients with hypertension regardless of sex.
ShRNA knock‐down of CXCR7 inhibits tumour invasion and metastasis in hepatocellular carcinoma after transcatheter arterial chemoembolization
Authors: Zhao Zhong‐Wei , Fan Xiao‐Xi , Song Jing‐Jing , Xu Min , Chen Min‐Jiang , Tu Jian‐Fei , Wu Fa‐Zong , Zhang Deng‐Ke , Liu Lu , Chen Li , Ying Xi‐Hui , Ji Jian‐Song
Published: April 2017

To investigate the effects of lentiviral vector‐mediated shRNA suppressing CXCR7 on tumour invasion and metastasis in hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE). HCCLM3 cell lines were cultured and assigned into the CXCR7‐shRNA, negative control (NC) and blank groups. The qRT‐PCR and Western blotting were applied to detect the mRNA and protein expressions of CXCR7, CXCR4 and MMP‐2 in HCCLM3 cells. Cell proliferation and invasion were evaluated by MTT and Transwell assays. A Buffalo rat model of HCC was established. Fifty model rats were divided into the CXCR7‐shRNA + TACE, CXCR7‐shRNA, TACE, NC and control groups. Immunohistochemistry was performed to detect the expressions of CXCR7, MMP‐2, vascular endothelial growth factor (VEGF) and intratumoral CD31‐positive vessel count in tumour tissues of mice. Compared with the blank and NC groups, the mRNA and protein expressions of CXCR7 and MMP‐2 were decreased in the CXCR7‐shRNA group. The cell proliferation and invasion rates of the CXCR7‐shRNA group were lower than the blank and NC groups. At the 4th week after TACE, tumour weight of the CXCR7‐shRNA + TACE group increased continuously. The CXCR7‐shRNA + TACE group showed longer survival time and smaller tumour sizes than other groups. Compared with other groups, the CXCR7‐shRNA + TACE and CXCR7‐shRNA groups had less number of lung metastatic nodules and lower expressions of CXCR7, MMP‐2, VEGF and CD31‐positive vessel count. CXCR7‐shRNA inhibits tumour invasion and metastasis to improve the efficacy of TACE in HCC by reducing the expressions of CXCR7, MMP‐2 and VEGF.
Melatonin antagonizes interleukin‐18‐mediated inhibition on neural stem cell proliferation and differentiation
Authors: Li Zheng , Li Xingye , Chan Matthew T.V. , Wu William Ka Kei , Tan DunXian , Shen Jianxiong
Published: April 2017

Neural stem cells (NSCs) are self‐renewing, pluripotent and undifferentiated cells which have the potential to differentiate into neurons, oligodendrocytes and astrocytes. NSC therapy for tissue regeneration, thus, gains popularity. However, the low survivals rate of the transplanted cell impedes its utilities. In this study, we tested whether melatonin, a potent antioxidant, could promote the NSC proliferation and neuronal differentiation, especially, in the presence of the pro‐inflammatory cytokine interleukin‐18 (IL‐18). Our results showed that melatonin per se indeed exhibited beneficial effects on NSCs and IL‐18 inhibited NSC proliferation, neurosphere formation and their differentiation into neurons. All inhibitory effects of IL‐18 on NSCs were significantly reduced by melatonin treatment. Moreover, melatonin application increased the production of both brain‐derived and glial cell‐derived neurotrophic factors (BDNF, GDNF) in IL‐18‐stimulated NSCs. It was observed that inhibition of BDNF or GDNF hindered the protective effects of melatonin on NSCs. A potentially protective mechanism of melatonin on the inhibition of NSC's differentiation caused IL‐18 may attribute to the up‐regulation of these two major neurotrophic factors, BNDF and GNDF. The findings indicate that melatonin may play an important role promoting the survival of NSCs in neuroinflammatory diseases.
Extreme ocean acidification reduces the susceptibility of eastern oyster shells to a polydorid parasite
Authors: Clements J C , Bourque D , McLaughlin J , Stephenson M , Comeau L A
Published: April 2017

Ocean acidification poses a threat to marine organisms. While the physiological and behavioural effects of ocean acidification have received much attention, the effects of acidification on the susceptibility of farmed shellfish to parasitic infections are poorly understood. Here we describe the effects of moderate (pH7.5) and extreme (pH7.0) ocean acidification on the susceptibility ofCrassostrea virginicashells to infection by a parasitic polydorid,Polydora websteri. Under laboratory conditions, shells were exposed to threepHtreatments (7.0, 7.5 and 8.0) for 3‐ and 5‐week periods. Treated shells were subsequently transferred to an oyster aquaculture site (which had recently reported an outbreak ofP. websteri) for 50 days to test for effects ofpHand exposure time onP. websterirecruitment to oyster shells. Results indicated thatpHand exposure time did not affect the length, width or weight of the shells. Interestingly,P. webstericounts were significantly lower under extreme (pH7.0; ~50% reduction), but not moderate (pH7.5; ~20% reduction) acidification levels; exposure time had no effect. This study suggests that extreme levels – but not current and projected near‐future levels – of acidification (∆pH~1 unit) can reduce the susceptibility of eastern oyster shells toP. websteriinfections.