bluuebunny/crossref_metadata_2025 huggingface dataset:
Horizontal transmission and recombination maintain forever young bacterial symbiont genomes
Authors: Russell Shelbi L. , Pepper-Tunick Evan , Svedberg Jesper , Byrne Ashley , Castillo Jennie Ruelas , Vollmers Christopher , Beinart Roxanne A. , Corbett-Detig Russ
Published: August 2019

Bacterial symbionts bring a wealth of functions to the associations they participate in, but by doing so, they endanger the genes and genomes underlying these abilities. When bacterial symbionts become obligately associated with their hosts, their genomes are thought to decay towards an organelle-like fate due to decreased homologous recombination and inefficient selection. However, numerous associations exist that counter these expectations, especially in marine environments, possibly due to ongoing horizontal gene flow. Despite extensive theoretical treatment, no empirical study thus far has connected these underlying population genetic processes with long-term evolutionary outcomes. By sampling marine chemosynthetic bacterial-bivalve endosymbioses that range from primarily vertical to strictly horizontal transmission, we tested this canonical theory. We found that transmission mode strongly predicts homologous recombination rates, and that exceedingly low recombination rates are associated with moderate genome degradation in the marine symbionts with nearly strict vertical transmission. Nonetheless, even the most degraded marine endosymbiont genomes are occasionally horizontally transmitted and are much larger than their terrestrial insect symbiont counterparts. Therefore, horizontal transmission and recombination enable efficient natural selection to maintain intermediate symbiont genome sizes and substantial functional genetic variation.

Author summary

Symbiotic associations between bacteria and eukaryotes are ubiquitous in nature and have contributed to the evolution of radically novel phenotypes and niches for the involved partners. New metabolic or physiological capacities that arise in these associations are typically encoded by the bacterial symbiont genomes. However, the association itself endangers the retention of bacterial genomic coding capacity. Endosymbiont genome evolution theory predicts that when bacterial symbionts become restricted to host tissues, their populations cannot remove deleterious mutations efficiently. This ultimately results in their genomes degrading to small, function-poor states, reminiscent of organellar genomes. However, many ancient marine endosymbionts do not fit this prediction, but instead retain relatively large, gene-rich genomes, indicating that the evolutionary dynamics of this process need more thorough characterization. Here we show that on-going symbiont gene flow via horizontal transmission between bivalve hosts and recombination among divergent gammaproteobacterial symbiont lineages are sufficient to maintain large and dynamic bacterial symbiont genomes. These findings indicate that many obligately associated symbiont genomes may not be as isolated from one another as previously assumed and are not on a one way path to degradation.
Are trade‐offs really the key drivers of ageing and life span?
Authors: Cohen Alan A. , Coste Christophe F. D. , Li Xiang‐Yi , Bourg Salomé , Pavard Samuel
Published: August 2019

Current thinking in life‐history theory and the biology of ageing suggests that ageing rates, and consequently life spans, evolve largely as a function of trade‐offs with reproduction. While various evolutionary constraints are generally acknowledged to exist, their potential role in determining ageing rates is rarely considered.

This review integrates three types of information to assess the relative importance of constraints and trade‐offs in shaping ageing rates: (a) empirical work on the presence of intraspecific trade‐offs; (b) theoretical work on factors limiting the force of trade‐offs; and (c) consideration of the biological mechanisms of ageing, as currently understood.

At the empirical level, evidence for intraspecific trade‐offs is mixed, including some surprising failures to observe a trade‐off in model organisms. At the theoretical level, the presence of multiple currencies and nonlinearity can weaken the strength and/or generality of trade‐offs. Additionally, trade‐offs among lower‐level functions, such as between sources of mortality, can create constraints at higher organizational levels, for example such that reductions in reproduction are unable to produce decreases in ageing rate. In terms of ageing mechanisms, some mechanisms, such as the regulation of IGF‐1 and related pathways, seem to agree quite well with trade‐offs as a driving force; however, other mechanisms, such as dysregulation of the vertebrate stress response and stem cell exhaustion, seem more likely to impose constraints than to mediate trade‐offs.

Taken together, these findings suggest that trade‐offs alone are insufficient to understand how ageing rates evolve; instead, both trade‐offs and constraints likely play important roles in shaping evolutionary patterns, with their relative importance varying across taxa. Accordingly, it is time to revisit the broad assumption that survival–reproduction trade‐offs are the key force structuring much of life‐history variation and the evolution of ageing rates.

A free Plain Language Summary can be found within the Supporting Information of this article.
P‐wave complex‐valued traveltimes in homogeneous attenuating transversely isotropic media
Authors: Hao Qi , Waheed Umair bin , Alkhalifah Tariq
Published: August 2019

Computation of complex‐valued traveltimes provides an efficient approach to describe the seismic wave attenuation for applications like attenuation tomography, inverse Q filtering and Kirchhoff migration with absorption compensation. Attenuating acoustic transverse isotropy can be used to describe the directional variation of velocity and attenuation of P‐waves in thin‐bedding geological structures. We present an approximate method to solve the acoustic eikonal equation for an attenuating transversely isotropic medium with a vertical symmetry axis. We take into account two similar parameterizations of an attenuating vertical symmetry axis medium. The first parameterization uses the normal moveout velocity, whereas the second parameterization uses the horizontal velocity. For each parameterization, we combine perturbation theory and the Shanks transform in different ways to derive analytic solutions. Numerical examples show that the analytic solutions derived from the second parameterization yield better accuracy. The Shanks transform solution with respect to only the anellipticity parameter from the second parameterization is demonstrated numerically to be the most accurate among all the analytic solutions.
‘Are we there yet?’ Australian HR professionals and the Fourth Industrial Revolution
Authors: Nankervis Alan , Connell Julia , Cameron Roslyn , Montague Alan , Prikshat Verma
Published: August 2019

Although still in its early stages, the Fourth Industrial Revolution (FIR), which involves a broad range of artificial intelligence, robotics and machine learning technologies, will fundamentally change the way many of us work and relate to one another. Driven by technology, this transformation presents a range of challenges, as well as opportunities, where we might expect Human Resource (HR) professionals would lead the way. However, little is currently known in relation to how prepared HR professionals in Australia are to ready their organisations for this new era of work and associated resourcing. Consequently, this paper goes some way towards closing that gap. Specifically, the study reported here sets out to explore the levels of preparedness amongst Australian HRM professionals for the impact of the FIR on organisations, workplaces, jobs and skills, as well as on their own professional roles and competencies. The study utilised a sequential mixed methods research design with two phases, the first was qualitative focus groups (n = 5) followed by a quantitative online survey of selected senior HR practitioners (n = 150). The findings indicate that, while most believe that FIR technologies might be useful for their organisations and assist with improving job performance, increasing productivity and making jobs easier for employees, contrarily many did not intend to use them in the foreseeable future. Marginal support was also evident in relation to the potential contributions of FIR technologies to HR process enhancement and overall HR effectiveness. Most respondents were also not impressed with the lack of current Australian government FIR strategies and policies.
Are Earnings Forecasts Informed by Proxy Statement Compensation Disclosures?
Authors: Larocque Stephannie A. , Martin Melissa A. , Walther Beverly R.
Published: August 2019

We investigate the extent to which market participants use compensation payouts released in the DEF 14A proxy statement (DEF14A) to assess future firm performance by examining sell‐side analysts' earnings forecasts. Consistent with prior work, we confirm that CEO compensation unexplained by current observable economic factors is positively associated with future firm performance. We find that both the likelihood that analysts revise their forecasts following release of the DEF14A and the magnitude and direction of analysts' forecast revisions are positively associated with unexplained CEO compensation. These associations are stronger after the SEC required additional compensation‐related disclosures in late 2006 but lower if the firm has weak corporate governance or more precise other information. Analysts' reactions are not complete, however. Analysts' forecast errors measured months after the DEF14A release are associated with past unexplained compensation, especially in the pre‐2006 period and for analysts who do not revise at the DEF14A release. Taken together, our results suggest that compensation payouts released in the DEF14A contain useful forward‐looking information that is recognized by at least some sophisticated market participants and that the increased disclosure regulations assisted market participants in incorporating this information.
Express Yourself: Why Managers' Disclosure Tone Varies Across Time and What Investors Learn from It
Authors: Campbell John L. , Lee Hye Seung “Grace” , Lu Hsin‐Min , Steele Logan B.
Published: August 2019

We argue that volatility in a manager's disclosure tone across time should be a function of two components: (i) the firm's innate operating risk and (ii) the extent to which the manager's disclosure transparently reflects that risk. Consistent with this argument, we find that both operating risk and disclosure transparency are important determinants of disclosure tone volatility. We then examine whether investors incorporate the incremental information provided by disclosure tone volatility into their assessments of firm risk. If disclosure tone volatility primarily provides investors with incremental information about a firm's operating risk, we should find a positive association between tone volatility and market‐based assessments of risk. On the other hand, if disclosure tone volatility primarily provides investors with incremental information about a manager's disclosure transparency, we should find a negative association between tone volatility and market‐based assessments of risk. Consistent with an operating risk explanation, we find a positive association between disclosure tone volatility and market‐based assessments of firm risk after controlling for a comprehensive set of proxies for operating risk and transparency. We find little support for an information risk explanation, even when we examine multiple measures specifically designed to capture information risk. Taken together, our results suggest that although disclosure tone volatility is a function of both a firm's operating risk and a manager's disclosure transparency, investors appear to respond as if disclosure tone volatility only provides incremental information about a firm's operating risk.
Toward a robust tool for pharmacokinetic‐based personalization of treatment with tacrolimus in solid organ transplantation: A model‐based meta‐analysis approach
Authors: Nanga Tom M. , Doan Thao T.P. , Marquet Pierre , Musuamba Flora T.
Published: August 2019

Aims

The objective of this study is to develop a generic model for tacrolimus pharmacokinetics modelling using a meta‐analysis approach, that could serve as a first step towards a prediction tool to inform pharmacokinetics‐based optimal dosing of tacrolimus in different populations and indications.

Methods

A systematic literature review was performed and a meta‐model developed with NONMEM software using a top‐down approach. Historical (previously published) data were used for model development and qualification. In‐house individual rich and sparse tacrolimus blood concentration profiles from adult and paediatric kidney, liver, lung and heart transplant patients were used for model validation. Model validation was based on successful numerical convergence, adequate precision in parameter estimation, acceptable goodness of fit with respect to measured blood concentrations with no indication of bias, and acceptable performance of visual predictive checks. External validation was performed by fitting the model to independent data from 3 external cohorts and remaining previously published studies.

Results

A total of 76 models were found relevant for meta‐model building from the literature and the related parameters recorded. The meta‐model developed using patient level data was structurally a 2‐compartment model with first‐order absorption, absorption lag time and first‐time varying elimination. Population values for clearance, intercompartmental clearance, central and peripheral volume were 22.5 L/h, 24.2 L/h, 246.2 L and 109.9 L, respectively. The absorption first‐order rate and the lag time were fixed to 3.37/h and 0.33 hours, respectively. Transplanted organ and time after transplantation were found to influence drug apparent clearance whereas body weight influenced both the apparent volume of distribution and the apparent clearance. The model displayed good results as regards the internal and external validation.

Conclusion

A meta‐model was successfully developed for tacrolimus in solid organ transplantation that can be used as a basis for the prediction of concentrations in different groups of patients, and eventually for effective dose individualization in different subgroups of the population.
Ten years of pulling: Ecosystem recovery after long‐term weed management in Garry oak savanna
Authors: Shackelford Nancy , Murray Sean M. , Bennett Joseph R. , Lilley Patrick L. , Starzomski Brian M. , Standish Rachel J.
Published: August 2019

Ecosystem restoration is the practice of assisting recovery in degraded ecological communities. The aims of restoration are typically broad, involving the reinstatement of composition, structure, function, and resilience to disturbances. One common restoration tactic in degraded urban systems is to control invasive species, relying on passive restoration for further ecosystem‐level recovery. Here, we test whether this is an effective restoration strategy in Garry oak savanna, a highly threatened and ecologically important community in the North American Pacific Northwest. In urban savanna patches surrounding Victoria, British Columbia, community members have been actively removing aggressive invasive exotic species for over a decade. Based on vegetation surveys from 2007, we tested ecosystem changes in structure, composition, and resilience (i.e., functional redundancy and response diversity) across 10 years of varied management levels. We expected higher levels of invasive species management would correspond with improvements to these ecosystem metrics. However, management explained little of the patterns found over the 10‐year‐period. Woody encroachment was a complicated process of native and exotic invasion, while resilience and compositional changes were most closely tied with landscape connectivity. Thus, though invasive species management may prevent further degradation, active restoration strategies after removal are likely required for recovery of the ecosystem.
Pediatric malignancies: Is the prechemotherapy left ventricular function normal?
Authors: Akam‐Venkata Jyothsna , Kadiu Gilda , Galas James , Aggarwal Sanjeev
Published: August 2019

Purpose

We compared the left ventricular (LV) systolic function in children with cancer before initiation of chemotherapy with matched controls using speckle tracking echocardiography.

Methods and results

In this retrospective study, we analyzed the echocardiograms of 89 cancer patients before the initiation of chemotherapy and 82 age‐ (8.4 ± 5.2 vs. 8.9 ± 3.9 years, P = .4) and gender‐matched (64% vs. 67%, males, P = .4) healthy controls. Peak systolic LV longitudinal strain (LS) was significantly lower in cancer patients in apical two (−19.8 ± 3.0 vs. −23.5 ± 4.0, P < .001), three (−19.4 ± 3.2 vs. −23.4 ± 4.0, P < .001), and four‐chamber views (−19.7 ± 3.4 vs. −22.5 ± 3.0, P < .001) compared to controls, as was global longitudinal strain (GLS) (−19.8 ± 2.7 vs. −23.4 ± 3.2, P < .001). The prechemotherapy group also had a higher E/e' ratio compared to controls at the septal (9.3 ± 3.9 vs. 7.9 ± 1.7, P = .005) and lateral annulus (7.9 ± 3.3 vs. 5.9 ± 1.4, P < .001) of the mitral valve. The LV ejection fraction was lower in cancer patients compared to controls (63.5 ± 4.9 vs. 66.8 ± 4.1, P < .001), although still within normal limits. There were no differences in LV myocardial performance index (0.30 ± 0.05 vs. 0.30 ± 0.09, P < .65) and shortening fraction (35.8 ± 5.2 vs. 36.1 ± 6.1, P < 0.75) between the two groups. Subgroup analysis showed no difference in LV GLS between patients with solid tumors (n = 56) and blood cancers (n = 33) (GLS −19.2 ± 2.9 vs. 19.5 ± 2.4, P > 0.05).

Conclusion

Our data demonstrating abnormalities in LV GLS in pediatric cancer patients even prior to initiation of chemotherapy are novel and perplexing. Further longitudinal follow‐up is required to assess the implications of this abnormal LV function in these patients.
Trends in the use of echocardiography in patients with Staphylococcus aureus bacteremia: an analysis using the Nationwide Inpatient Sample data
Authors: Urja Prakrity , Walters Ryan W. , Vivekanandan Renuga , Kumar Mukund , Abdulghani Saadi , Hari Belbase Ram , Zook Nina , Mahesh Alla Venkata
Published: August 2019

Background

Infective endocarditis occurs in approximately 10%‐30% of patients with Staphylococcus aureus bacteremia (SaB). Guidelines recommend echocardiography in patients with SaB and risk factors for infective endocarditis in the absence of any obvious source of infection. Herein, we explored the trends in the use of echocardiography in patients with SaB and its relationship to outcomes using a large national database.

Method

All patients with a principal discharge diagnosis of SaB were identified using the National Inpatient Sample database from 2001 to 2014. Procedure code 88.72 was used to identify echocardiography. Logistic regression models were estimated to identify the year‐over‐year trends in echocardiogram, predictors of use, and association with mortality.

Results

From 2001 to 2014, there were 668 423 hospitalizations with SaB diagnosis and 86 387 (12.9%) had echocardiogram. The rate of echocardiography increased from 10.7% in 2001 to 15.2% in 2014 (ptrend < 0.001). Major predictors of echocardiogram usage were younger age, male gender, presence of sepsis, valvular or congenital heart disease, prosthetic heart valve (PHV), cardiac implantable electronic device (CIED), hemodialysis, and drug abuse. The adjusted rates of echocardiography increased from approximately 10% to 15% in hospitalizations without risk factors for IE while for high‐risk groups like PHV and CIED it remained constant at 30% and 19%, respectively. Echocardiography was associated with 31% lower odds of in‐hospital mortality.

Conclusion

The increase in echocardiography rate was largely attributable to increased use in those without risk factors while usage in those with PHV and CIED remained much lower than expected. Echocardiography use was associated with lower risk‐adjusted mortality. These findings require further study and confirmation.
Differential effects of dopamine D1‐like and D2‐like receptor agonists on water drinking behaviour under thirsty conditions in mice with reduced dopamine secretion
Authors: Kao Kung‐Chun , Hisatsune Tatsuhiro
Published: August 2019

The mesolimbic dopamine system is important for reward‐oriented behaviours, such as drinking and eating. However, the precise involvement of dopaminergic neurons and dopamine receptors in water drinking behaviour remains unclear. Here, we generated triple transgenic mice harbouring Slc6a3(DAT)‐icre/ERT2, Camk2a‐loxP‐STOP‐loxP‐tetracycline transactivator and tetO‐tetanus toxin constructs, in which the release of dopamine is blocked by tetanus toxin. These mice, referred to as dopamine secretion interference mice, had reduced dopamine secretion in the striatum (61.4%) and the nucleus accumbens (54.5%). They showed adequate limb strength and food consumption, similarly to control mice, but exhibited motor control impairment in a challenging rotarod test. Dopamine secretion interference mice made fewer licks and had fewer bursts than control mice during a licking test under thirsty conditions. To elucidate the influence of dopamine receptors in the altered drinking behaviour, a dopamine D1 or D2/D3 receptor agonist (A68930 or ropinirole, respectively) was administered prior to the licking microstructure analysis. Treatment with the D1 agonist restored the total number of licks but not the burst number in dopamine secretion interference mice. By contrast, the D2/3 agonist impeded water drinking behaviour in both transgenic and control mice. The present findings indicate that D1 receptor activation partially ameliorates the altered drinking behaviour of the dopamine secretion interference mice and suggest that D1 receptor activity impacts drinking under thirsty conditions.
Evaluation of safety, humoral immune response and faecal shedding in horses inoculated with a modified‐live bovine coronavirus vaccination
Authors: Prutton J. S. W. , Barnum S. , Pusterla N.
Published: August 2019

Equine coronavirus (ECoV) is considered an emerging enteric virus with reported morbidity rates ranging from 10 to 83% and fatality rates ranging from 7 to 27% in adult horses; a vaccine for ECoV is currently not available. This study investigated the safety, humoral response and viral shedding in horses inoculated with a commercially available modified‐live bovine coronavirus (BCoV) vaccine. Twelve healthy adult horses were vaccinated twice, 3 weeks apart, either orally, intranasally or intrarectally. Two healthy unvaccinated horses served as sentinel controls. Following each vaccine administration, horses were monitored daily for physical abnormalities whilst the onset and duration of BCoV shedding was determined by quantitative PCR (qPCR) in nasal secretions and faeces. Whole blood was collected every 3 weeks to determine BCoV‐specific antibody response. With the exception of transient and self‐limiting changes in faecal character observed in seven vaccinated and one control horse, no additional abnormal clinical findings were found in the study horses. Following the first and second vaccine administration, two and one horse, respectively, tested qPCR‐positive for BCoV in nasal secretions 1‐day post intranasal vaccination. No vaccinated horses tested qPCR‐positive for BCoV in faeces following each vaccine administration. One of the two horses that shed BCoV seroconverted to BCoV after the first vaccine administration and an additional two vaccinated horses (oral and intrarectal) seroconverted to BCoV after the second vaccine administration. In conclusion, the results show that the modified‐live BCoV is safe to administer to horses via various routes, causes minimal virus shedding and results in detectable antibodies to BCoV in 27% of the vaccinates.
Recumbency following diagnostic analgesia of the sacroiliac joint regions: 15 horses
Authors: Nagy A. , Dyson S.
Published: August 2019

Sacroiliac (SI) joint region pain is relatively common in sports horses and diagnosis is ideally confirmed by diagnostic analgesia (SI joint region blocks). Anecdotal reports describe complications following SI joint region blocks, but there is no detailed published information. Our aim was to document a series of horses that became recumbent following SI joint region blocks. Clinicians were asked to participate via the e‐mail list of the American College of Veterinary Sports Medicine and Rehabilitation and by contacting clinicians known to the authors to investigate poor performance and lameness in sports horses. Horses (n = 15) were included if they became recumbent following SI joint region blocks, with or without using other substances in addition to local anaesthetic solution. Data on the clinicians’ experience, injection technique, clinical findings before and while the horse was recumbent and the outcome were collected in an online questionnaire. The clinicians’ experience and injection techniques varied. In three horses corticosteroids, with or without pitcher plant extract, were also injected with the local anaesthetic solution. In 14 horses, the injection(s) were performed at a clinic or hospital; 13 horses were injected in stocks. Seven horses were sedated for the procedure. Fourteen horses became recumbent within 10 min and one within 20 min. While recumbent, seven horses were sedated and six anaesthetised. Fourteen horses stood up at a mean time of 3.8 h after becoming recumbent; additional information was available for 13 horses, all of which made a complete recovery. Three horses suffered temporary complications (pneumonia related to intubation, abrasions from a sling and radial nerve dysfunction associated with slinging). One horse was euthanised after 3 days because of failure to regain hindlimb function. In conclusion, recumbency following diagnostic analgesia of the SI joint regions can occur, but in the majority of horses, it has no long‐term consequences.
Family as a eudaimonic bubble: Women entrepreneurs mobilizing resources of care during persistent financial crisis and austerity
Authors: Meliou Elina
Published: August 2019

Drawing on the conceptualization of family as a eudaimonic bubble, the study explores how women entrepreneurs mobilize familial resources to navigate the gendered challenges faced during persistent financial crisis and austerity in Greece, a country affected by acute socioeconomic crisis. Through qualitative interviews with women who started their own business during the financial crisis, it investigates how the allocation of resources and opportunities built on care enabled women to start and sustain their own business and achieve a degree of normative conformity, creating social cohesion in the here and now. The analysis reveals the transformational potential of familial care by illustrating three modes of resources of care that contribute to business viability, and positions the family, an organizing principle, in the centre of research on gendered mobilizations in crisis economies. In that way, the study critically contributes to debates regarding gender, entrepreneurship and austerity.
Identification of heterozygous p.Y150C and p.V274M mutations in the HJV gene in a Japanese patient with a mild phenotype of juvenile hemochromatosis: A case report
Authors: Kawaguchi Takumi , Ikuta Katsuya , Tatsumi Yasuaki , Toki Yasumichi , Hayashi Hisao , Tonan Tatsuyuki , Ohtake Takaaki , Hoshino Seiichiro , Naito Masayasu , Kato Koichi , Okumura Toshikatsu , Torimura Takuji
Published: August 2019

Juvenile hemochromatosis (JH) is known as a progressive iron‐storage disease, and causes severe organ impairments, including cardiomyopathy and liver cirrhosis. However, JH is a rare genetic disorder, and information for genetic mutations and phenotypes is limited. Here, we report a case of JH with heterozygous p.Y150C and p.V274M mutations in the HJV gene. A 39‐year‐old Japanese man was referred to Kurume University Hospital, Kurume, Japan, for fatigue and liver injury, which first appeared at the age of 25 years. There was no history of alcohol abuse and medication, and viral hepatitis, autoimmune liver diseases, and Wilson's disease were absent. However, transferrin saturation, serum ferritin, and fasting serum hepcidin levels were 98.4%, 6421 ng/mL, and 7.4 ng/mL, respectively. Furthermore, a marked reduction in signal intensity of the liver in T1/T2‐weighted magnetic resonance images was seen and the R2* maps showed hepatic iron overload. Family history of hemochromatosis and severe organ impairment, such as cardiac dysfunction and diabetes mellitus, were negative. In addition, the HFE and HAMP genes did not show any mutation. However, we identified novel heterozygous p.Y150C and p.V274M mutations in the HJV gene in the patient. The p.Y150C and p.V274M mutations were seen in his mother and father, respectively. After phlebotomy, fatigue disappeared and serum transaminase levels were normalized. Furthermore, R2* maps showed a reduction of hepatic iron concentration. We first demonstrated heterozygous p.Y150C and p.V274M mutations in the HJV gene of patients with a mild JH phenotype. Thus, genetic testing should be considered even in patients with a mild phenotype of hemochromatosis.
Atypical lipomatous tumour/well‐differentiated liposarcoma and de‐differentiated liposarcoma in patients aged ≤ 40 years: a study of 116 patients
Authors: Waters Rebecca , Horvai Andrew , Greipp Patricia , John Ivy , Demicco Elizabeth G , Dickson Brendan C , Tanas Munir R , Larsen Brandon T , Ud Din Nasir , Creytens David H , Bahrami Armita , Doyle Leona A , Jo Vickie Y , Al‐Ibraheemi Alyaa , Thway Khin , Jenkins Sarah M , Siontis Brittany , Folpe Andrew , Fritchie Karen
Published: August 2019

Aims

Limited data exist on atypical lipomatous tumour (ALT)/well‐differentiated liposarcoma (WDL) and de‐differentiated liposarcoma (DDLPS) in children and young adults.

Methods and results

Cases of ALT/WDL/DDLPS arising in patients aged ≤ 40 years were collected from multiple institutional and consultation archives. A total of 116 cases of ALT/WDL (75) and DDLPS (41) were identified, representing fewer than 5% of these tumours seen at our institutions during this time‐period. The patients (59 male/57 female) ranged in age from 8 to 40 years. Sites included deep central (abdomen/retroperitoneum/pelvis/groin) (n = 60), extremity (n = 42), trunk (n = 5), head/neck (n = 8) and mediastinum (n = 1). De‐differentiated patterns included: high‐grade pleomorphic sarcoma, myxofibrosarcoma‐like, heterologous rhabdomyoblastic differentiation, low‐grade spindle cell sarcoma and homologous lipoblastic differentiation. Forty‐one patients experienced a local recurrence and 11 patients with DDLPS developed metastasis. ALT arising in the extremities had lower recurrence rates than deep central WDL (5‐year recurrence‐free survival 88.9% versus 59.0%; P = 0.002), while patients with deep central DDLPS experienced significantly more adverse events compared to WDL at this site (5‐year event‐free survival 11.9% versus 59.0%) (P < 0.0001). Seven (of eight) head/neck tumours had follow‐up available; five recurred, and one patient (DDLPS) with recurrence also experienced a metastasis. The single mediastinal tumour (DDLPS) recurred and metastasised.

Conclusion

ALT/WDL and DDLPS occurring in patients aged ≤ 40 years is rare, but exhibits similar morphological features to its counterparts in older adults, including potential for heterologous and homologous de‐differentiation in the latter. Although case numbers are limited, tumours arising in the head and neck exhibit high rates of adverse events, suggesting that classification as WDL rather than ALT is more appropriate.
Effect and mechanism of ZrO2 doping on the cracking behavior of melt‐grown Al2O3 ceramics prepared by directed laser deposition
Authors: Wu Dongjiang , San Junde , Niu Fangyong , Zhao Dake , Liang Xiaokang , Yan Shuai , Ma Guangyi
Published: August 2019

Directed laser deposition (DLD) is a new method for rapidly preparing melt‐grown ceramics, but cracking problem greatly limited its application. In this study, cracking behavior of Al2O3 ceramics was suppressed by doping ZrO2. Crack suppression mechanism of ZrO2 doping in melt‐grown ceramics was also analyzed. Process parameters which are prone to generating cracks were adopted in the experiments, and they contribute to showing the crack clearly. Results show that ZrO2 doping has remarkable crack suppression effects. It is most obvious when ZrO2 content is 37 mol%. Compared with those of pure Al2O3 ceramics, crack density reduces by 43.2%, and the number of longitudinal main cracks reduces by 63.2%. Doping of ZrO2 forms dense composite microstructure with primary α‐Al2O3 grains discretely distributing in eutectic continuous matrix. Therefore, initial crack sources are effectively reduced. Morphology of primary Al2O3 grains transforms from cellular to dendritic, which changes crack propagation mode from inter‐granular to trans‐granular. Mismatch of thermo‐physical properties of different phase promotes the arrest, deflection, and bridging phenomena in crack propagation, contributing to crack suppression. On the basis of ZrO2 doping, we have realized the preparation of crack‐free eutectic ceramic (37 mol%ZrO2) samples through further process optimization. The maximum size of the sample reaches 230 mm.
Density difference in pressure‐filtrated wet cakes produced from spontaneous gelling slurries
Authors: Di Zhengxian , Shimai Shunzo , Zhao Jin , Jin Dongliang , Zhang Jian , Zhou Guohong , Liu Juan , Wang Shiwei
Published: August 2019

Pressure filtration is a key process in ceramic forming; however, the influences of density difference in different parts of a pressure‐filtrated wet cake on subsequent drying and sintering have not yet been explored. In the present work, alumina slurries dispersed by copolymers of isobutylene and maleic anhydride (PIBM) and ammonium salt of polyacrylic acid (PAANH4) were pressure filtrated to examine the impacts of density difference in the as‐prepared wet cakes. In comparison to the wet cake produced from PAANH4, the wet cake with PIBM had much higher bulk density and smaller density difference between its upper and bottom parts (height of ~23 mm). Furthermore, in order to reveal the differences between these two wet cakes, the nature of agglomerates in their slurries was investigated. The slurry with PIBM contained agglomerates with a wider size distribution, bigger average size, and higher sphericity, producing a wet cake with a higher particle packing density and more homogeneous packing structure after pressure filtration. Hence, almost no deformation occurred in a large wet cake (280 mm × 130 mm × 20 mm) with PIBM, whereas that with PAANH4experienced a severe deformation after sintering.
Supraventricular tachycardia with atrial activation earliest at the His bundle region—What is the mechanism?
Authors: Chen Qiufan , Liu Qiang , Jiang Chenyang
Published: August 2019

A 70‐year‐old man with recurrent symptomatic supraventricular tachycardia was referred for catheter ablation. Atrial activation was earliest at the His bundle region with HA longer than AH.
A high BNP level predicts an improvement in exercise tolerance after a successful catheter ablation of persistent atrial fibrillation
Authors: Katsumata Yoshinori , Tamura Yuichi , Kimura Takehiro , Kohsaka Shun , Sadahiro Taketaro , Nishiyama Takahiko , Aizawa Yoshiyasu , Azuma Koichiro , Fukuda Keiichi , Takatsuki Seiji
Published: August 2019

Introduction

Restoration of sinus rhythm (SR) by catheter ablation (CA) of atrial fibrillation (AF) improves exercise tolerance. However, it is still unclear what characteristics of patients are contributing to an improvement in exercise tolerance after CA of AF without heart failure.

Methods and results

This study consisted of 51 consecutive patients with persistent or long‐standing persistent AF without heart failure who were restored to SR for over 6 months by a successful CA. Exercise tolerance was evaluated by cardiopulmonary exercise testing before and 3 and 6 months after CA. The clinical characteristics contributing to an improvement in exercise tolerance was elucidated. The peak oxygen uptake (VO2)% significantly increased from 101.4 ± 20.3% to 110.9 ± 19.9% 3 months after the CA (P < .001). The improvement rate in the peak VO2% exhibited a positive correlation to the baseline brain natriuretic peptide (BNP; ρ = 0.39, P < .01), but not to the age, AF duration, left ventricular ejection fraction, or left atrial size. The linear regression analysis revealed that the baseline BNP was an independent predictor of an improvement in the peak VO2% (coefficients = 0.32; 95% conﬁdence interval = 0.08, 0.54; P = .01). The peak VO2% improved significantly in the patients whose baseline BNP level was greater than 100 pg/mL, compared to the others (P < .01). These favorable findings were also observed 6 months after the CA.

Conclusion

Elimination of persistent AF by CA was associated with an improvement in exercise tolerance. This was particularly true in patients with high BNP values at baseline.
Impaired orthostatic blood pressure stabilization and reduced hemoglobin in chronic kidney disease
Authors: Liu Wenjin , Wang Lulu , Huang Xiaoqin , He Weichun , Song Zongwei , Yang Junwei
Published: August 2019

Impaired orthostatic blood pressure (BP) stabilization is prevalent in patients with chronic kidney disease (CKD) and is associated with adverse outcomes. We aimed to test the hypothesis that reduced hemoglobin is an important contributor to orthostatic intolerance in CKD in the present study. This study included 262 patients with non‐dialysis‐dependent CKD. Seated and standing BP was measured, and orthostatic BP reduction was calculated for both systolic BP (∆ SBP) and diastolic BP (∆ DBP). The association between orthostatic BP reduction and hemoglobin was determined by multiple linear regression models. We also performed mediation analysis to test to what extent the effect of renal dysfunction on impaired orthostatic BP stabilization can be explained by reduced hemoglobin. The mean age of the patients was 57.7 (±14.5) years, and 61.5% were male. Both ∆ SBP and ∆ DBP correlated negatively with estimated glomerular filtration rate (eGFR). With adjustment for age and sex, hemoglobin level was negatively associated with ∆ SBP (β = −1.4, SE = 0.4, P < .001) and ∆ DBP (β = −0.6, SE = 0.2, P = .009). The associations remained significant with further adjustment for additional covariates. When eGFR was introduced as a covariate, it did not eliminate the significance (both P < .05). The associations remained essentially unchanged in a sensitivity analysis excluding those with concurrent erythropoietin use. Mediation analysis demonstrated that reduced hemoglobin accounted for 35.4% (P = .004) of the effect of eGFR on ∆ SBP and 47.7% (P = .032) on ∆ DBP. Our study suggests that reduced hemoglobin is a potentially important contributor to the development of orthostatic hypotension in CKD.
Dent disease: A window into calcium and phosphate transport
Authors: Anglani Franca , Gianesello Lisa , Beara‐Lasic Lada , Lieske John
Published: August 2019

This review examines calcium and phosphate transport in the kidney through the lens of the rare X‐linked genetic disorder Dent disease. Dent disease type 1 (DD1) is caused by mutations in the CLCN5 gene encoding ClC‐5, a Cl−/H+ antiporter localized to early endosomes of the proximal tubule (PT). Phenotypic features commonly include low molecular weight proteinuria (LMWP), hypercalciuria, focal global sclerosis and chronic kidney disease; calcium nephrolithiasis, nephrocalcinosis and hypophosphatemic rickets are less commonly observed. Although it is not surprising that abnormal endosomal function and recycling in the PT could result in LMWP, it is less clear how ClC‐5 dysfunction disturbs calcium and phosphate metabolism. It is known that the majority of calcium and phosphate transport occurs in PT cells, and PT endocytosis is essential for calcium and phosphorus reabsorption in this nephron segment. Evidence from ClC‐5 KO models suggests that ClC‐5 mediates parathormone endocytosis from tubular fluid. In addition, ClC‐5 dysfunction alters expression of the sodium/proton exchanger NHE3 on the PT apical surface thus altering transcellular sodium movement and hence paracellular calcium reabsorption. A potential role for NHE3 dysfunction in the DD1 phenotype has never been investigated, either in DD models or in patients with DD1, even though patients with DD1 exhibit renal sodium and potassium wasting, especially when exposed to even a low dose of thiazide diuretic. Thus, insights from the rare disease DD1 may inform possible underlying mechanisms for the phenotype of hypercalciuria and idiopathic calcium stones.
Symptom‐specific effects of cognitive‐behavioral therapy, sertraline, and their combination in a large randomized controlled trial of pediatric anxiety disorders
Authors: Cervin Matti , Storch Eric A. , Piacentini John , Birmaher Boris , Compton Scott N. , Albano Anne Marie , Gosch Elizabeth , Walkup John T. , Kendall Philip C.
Published: August 2019

Background

Pediatric anxiety disorders are highly prevalent and associated with significant functional disabilities and lifelong morbidity. Cognitive‐behavioral therapy (CBT), sertraline, and their combination are effective treatments, but little is known about how these treatments exert their effects.

Methods

Using network intervention analysis (NIA), we analyzed data from the largest randomized controlled treatment trial of pediatric anxiety disorders (Child/Adolescent Anxiety Multimodal Study, NCT00052078, clinicaltrials.gov/ct2/show/NCT00052078) and outlined the causal symptom domain‐specific effects of CBT, sertraline, and their combination over the course of the 12‐week treatment while taking into account both specificity and overlap between symptom domains.

Results

All active treatments produced positive effects with the most pronounced and consistent effects emerging in relation to psychological distress, family interference, and avoidance. Psychological distress was consistently the most and physical symptoms the least central symptom domain in the disorder network.

Conclusions

All active treatments showed beneficial effects when compared to placebo, and NIA identified that these effects were exerted similarly across treatments and primarily through a reduction of psychological distress, family interference, and avoidance. CBT and sertraline may have differential mechanisms of action in relation to psychological distress. Given the lack of causal effects on interference outside family and physical symptoms, interventions tailored to target these domains may aid in the building of more effective treatments. Psychological distress and avoidance should remain key treatment focuses because of their central roles in the disorder network. The findings inform and promote developing more effective interventions.
We know DAAs work, so now what? Simplifying models of care to enhance the hepatitis C cascade
Authors: Lazarus J. V. , Pericàs J. M. , Picchio C. , Cernosa J. , Hoekstra M. , Luhmann N. , Maticic M. , Read P. , Robinson E. M. , Dillon J. F.
Published: August 2019

Globally, some 71 million people are chronically infected with hepatitis C virus (HCV). Marginalized populations, particularly people who inject drugs (PWID), have low testing, linkage to care and treatment rates for HCV. Several models of care (MoCs) and service delivery interventions have the potential to improve outcomes across the HCV cascade of care, but much of the relevant research was carried out when interferon‐based treatment was the standard of care. Often it was not practical to scale‐up these earlier models and interventions because the clinical care needs of patients taking interferon‐based regimens imposed too much of a financial and human resource burden on health systems. Despite the adoption of highly effective, all‐oral direct‐acting antiviral (DAA) therapies in recent years, approaches to HCV testing and treatment have evolved slowly and often remain rooted in earlier paradigms. The effectiveness of DAAs allows for simpler approaches and has encouraged countries where the drugs are widely available to set their sights on the ambitious World Health Organization (WHO) HCV elimination targets. Since a large proportion of chronically HCV‐infected people are not currently accessing treatment, there is an urgent need to identify and implement existing simplified MoCs that speak to specific populations’ needs. This article aims to: (i) review the evidence on MoCs for HCV; and (ii) distil the findings into recommendations for how stakeholders can simplify the path taken by chronically HCV‐infected individuals from testing to cure and subsequent care and monitoring.
Linking customer participation to service employees’ work‐to‐family enrichment: The role of job crafting and OBSE
Authors: Loi Raymond , Xu Angela J. , Chow Cheris W.C. , Chan Wilco W.H.
Published: August 2019

Building on work–home resources model, we develop a conceptual model examining job crafting as the mediator between perceived customer participation and service employees’ work‐to‐family enrichment, and organization‐based self‐esteem (OBSE) as the moderator on this indirect relationship. Using two‐wave survey data collected from hotel service employees, we found that customer participation can enrich employees’ family role through increased cognitive and relational job crafting. In addition, employees’ OBSE accentuates the positive linkage between customer participation and employees’ relational crafting, and subsequently their work‐to‐family enrichment. This study makes important contributions to extant literature on work‐to‐family enrichment and job crafting as well. It also carries important implications for organizations to support employees’ proactive participation in job crafting and enrich employees’ family life.

Practitioner points

Organizations should well manage customer participation in order to enhance service employees’ job crafting.

Managers should be aware of how different types of job crafting can enrich their employees’ family domain.

To cultivate effective work‐to‐family enrichment, organizations should develop employees’ self‐worth and sense of competence within the organization.
Using decalcified collagen scaffolds to improve healing after transoral partial glossectomy for squamous cell carcinoma
Authors: Tahim Arpan , Sadiq Zaid
Published: August 2019

Introduction

Transoral partial glossectomy procedures for small squamous cell carcinomas of the anterior tongue often leave significant defects which are challenging to reconstruct. Post‐operative scarring leads to adhesions, reduced tongue mobility and limitations of function. We present a series of cases where a decalcified collagen scaffold was successfully used in this challenging reconstructive setting.

Methods

After standard oncological diagnostic and workup, five patients underwent transoral partial glossectomy procedures. Decalcified collagen scaffolds were used to reconstruct the surgical defect using a standard protocol. Demographic and outcome data were collected retrospectively.

Results

The median length of post‐operative stay was 5 days. There was no reported post‐operative bleeds or infection. Histological margins were clear. Scaffolds remained in situ at 1 week, and functional recovery was apparent at 6 weeks post‐procedure.

Discussion

These results suggest such scaffolds could be used as an adjunct to help reconstruct the anterior tongue after oncological resection.

Conclusion

The study supports a call for further exploration and research into the use of these scaffolds as a potentially beneficial avenue for reconstructing the tongue.