bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Early Progressive Resistive Exercise Therapy on Balance Control of Patients With Total Knee Arthroplasty
Authors: Yousefian Molla Razieh , Sadeghi Heydar , Kahlaee Amir Hossein
Published: October 2017

Background and Purpose:

Although total knee arthroplasty (TKA) is a common treatment for severe osteoarthritis, high risks of fall and balance loss are the main complications of this procedure. While multiple rehabilitation protocols have been suggested for TKA, efficacy of early resistive exercise therapy aimed at improving balance has not yet been thoroughly investigated.

Methods:

In this double-blind randomized controlled trial study, 40 patients with severe osteoarthritis, sampled by a simple convenient method, were randomly assigned into either “control” group or “early resistive exercise” group. After TKA surgery, both groups attended a routine rehabilitation program while the experimental group received extra early resistive exercises. Static, semidynamic, and dynamic balance were assessed by the Sharpened Romberg (SRBT), Star Excursion (SEBT), and Berg (BBT) balance tests prior to surgery, after the rehabilitation process (seventh week), and at a 2-week later follow-up time (ninth week).

Results:

At the end of the seventh and ninth weeks, in both groups all 3 balance scores were significantly enhanced comparing the baseline scores (P< .001). The experimental group had significantly higher scores than the control group in SRBT, SEBT, and BBT after the intervention and at the follow-up time (P< .001).

Discussion and Conclusions:

The findings of this study showed that rehabilitation following TKA is accompanied by balance (static, semidynamic, and dynamic) improvement, and this improvement is greater among patients participating in an early resistive exercise regimen. Early progressive resistive exercise in addition to routine physical therapy may lead to better balance performance than routine physical therapy and might be incorporated into the postoperative physical therapy of these patients. Further studies with longer follow-up periods are needed to confirm these results.
The Effects of a Dance-Based Program on the Postural Control in Older Women
Authors: Rodacki André Luiz Felix , Cepeda Christina Paramustchak Cruz , Lodovico Angélica , Ugrinowitsch Carlos
Published: October 2017

This study investigated the effect of an 8-week dance-based program on the postural control and functional capacity in older women. Thirty women were assigned onto 2 groups: ballroom dancing (DG: n = 15; 69.1 ± 6.6 years) and control group (CG: n = 15; 71.5 ± 7.5 years). The DG improved functional performance (6-minute walk, the Tinetti test, and the Time Up and Go tests), static balance (center of pressure path length, mean sway velocity, median frequency sway area), and dynamic balance (step test) (P < .05), whereas the CG remained unaltered. Dance-based programs are attractive to produce balance and functional performance gains in older adults.
Supporting Patient Provider Communication Across Medical Settings
Authors: Nordness Amy S. , Beukelman David R.
Published: October 2017

Medical errors and poor patient care have been impacted by communication failures despite mandates for effective patient–provider communication (The Joint Commission, 2010). There are a high number of communication vulnerable individuals in medical situations due to new medical conditions, preexisting conditions, and language differences, to name a few. The purpose of this article is to highlight strategies to support consistent, effective patient–provider communication in a medical setting. However, to guarantee patient–provider communication is consistent, policies and procedures must be in place to ensure appropriate orders are activated in a timely manner, personnel are assigned to support patient–provider communication, individualized communication needs are recognized and met, and quality measures are in place to ensure that high standards continue over time.
Health Care Provider Accommodations for Patients With Communication Disorders
Authors: Burns Michael I. , Baylor Carolyn , Dudgeon Brian J. , Starks Helene , Yorkston Kathryn
Published: October 2017

Health care providers can experience increased difficulty communicating with adult patients during medical interactions when the patients have communication disorders. Meeting the communication needs of these patients can also create unique challenges for providers. The authors explore Communication Accommodation Theory (H. Giles, 1979) as a guide for helping providers learn to adapt, or accommodate, their communication style at the appropriate level (neither too much nor too little) when their patients have communication disorders. Using principles of Communication Accommodation Theory, this article navigates case examples of medical interactions involving 2 hypothetical patients, 1 with aphasia and 1 with dysarthria. We use these two patients to illustrate some appropriate accommodations for patients with aphasia or dysarthria. Suggested accommodations stem from the FRAME mnemonic for communicating with patients with communication disorders and are organized using SEGUE, a framework outlining specific steps in a typical medical interaction. This article may also serve as a resource for speech–language pathologists providing in-services to their health care colleagues on this topic and to support interprofessional practices.
Central vertigo
Authors: Choi Jeong-Yoon , Lee Seung-Han , Kim Ji-Soo
Published: October 2017

Purpose of review

This review considers recent advances in central vertigo in terms of clinical and laboratory features and pathophysiology.

Recent findings

Strokes presenting dizziness–vertigo are more likely to be associated with a misdiagnosis in the emergency setting. The risk of future strokes after discharge is higher in patients diagnosed with peripheral vertigo than in control patients. Strokes and transient ischemic attacks account for one-quarter of acute transient vestibular syndrome. Diagnosis of acute combined central and peripheral vestibulopathy such as anterior inferior cerebellar artery infarction requires additional consideration whenever applying the HINTS (head impulse test, direction-changing gaze-evoked nystagmus, and test of skew). Heat illness and metronidazole have been recognized as new causes of central vestibulopathy. Some new findings have also been added to the clinical and laboratory features of central vertigo.

Central vertigo is a heterogeneous group of disorders with diverse clinical spectrums. An integrated approach based on understanding of clinical features, laboratory findings, speculated mechanisms, and limitations of current diagnostic tests will lead to better clinical practice.
Controlling septin filament flexibility and bundling
Authors: Khan Anum , Newby Jay , Gladfelter Amy S
Published: October 2017

Septins self-assemble into heteromeric rods and filaments to act as scaffolds and modulate membrane properties. How cells tune the biophysical properties of septin filaments to control filament flexibility and length, and in turn the size, shape, and position of higher-order septin structures is not well understood. We examined how rod composition and nucleotide availability influence physical properties of septins such as annealing, fragmentation, bundling and bending. We found that septin complexes have symmetric termini, even when both Shs1 and Cdc11 are coexpressed. The relative proportion of Cdc11/Shs1 septin complexes controls the biophysical properties of filaments and influences the rate of annealing, fragmentation, and filament flexibility. Additionally, the presence and exchange of guanine nucleotide also alters filament length and bundling. An Shs1 mutant that is predicted to alter nucleotide hydrolysis has altered filament length and dynamics in cells and impacts cell morphogenesis. These data show that modulating filament properties through rod composition and nucleotide binding can control formation of septin assemblies that have distinct physical properties and functions.
Unstable Population Dynamics in Obligate Co-Operators
Authors: Halloway Abdel , Malone Margaret A. , Brown Joel S.
Published: October 2017

Cooperation significantly impacts a species’ population dynamics as individuals choose others to associate with based upon fitness opportunities. Models of these dynamics typically assume that individuals can freely move between groups. Such an assumption works well for facultative co-operators (e.g. flocking birds, schooling fish, and swarming locusts) but less so for obligate co-operators (e.g. canids, cetaceans, and primates). With obligate co-operators, the fitness consequences from associations are stronger compared to facultative co-operators. Consequently, individuals within a group should be more discerning and selective over their associations, rejecting new members and even removing current members. Incorporating such aspects into population models may better reflect obligately cooperative species. In this paper, we create and analyze a model of the population dynamics of obligate co-operators. In our model, a behavioral game determines within-group population dynamics that then spill over into between-group dynamics. Our analysis shows that group number increases when population dynamics are stable, but additional groups lead to unstable population dynamics and an eventual collapse of group numbers. Using a more general analysis, we identify a fundamental mismatch between the stability of the behavioral dynamics and the stability of the population dynamics. When one is stable, the other is not. Our results suggest that group turnover may be inherent to the population dynamics of obligate co-operators. The instability arises from a non-chaotic deterministic process, and such dynamics should be predictable and testable.
N-acetyl-2-aminofluorene (AAF) processing in adult rat hepatocytes in primary culture occurs by high-affinity low-velocity and low-affinity high-velocity AAF metabolite-forming systems
Authors: Koch K.S. , Moran T. , Shier W.T. , Leffert H.L.
Published: October 2017

N-acetyl-2-aminofluorene (AAF) is a procarcinogen used widely in physiological investigations of chemical hepatocarcinogenesis. Its metabolic pathways have been described extensively, yet little is known about its biochemical processing, growth cycle expression and pharmacological properties inside living hepatocytes ‒ the principal cellular targets of this hepatocarcinogen. In this report, primary monolayer adult rat hepatocyte cultures and high specific-activity [ring G-3H]-N-acetyl-2-aminofluorene were used to extend previous observations of metabolic activation of AAF by highly differentiated, proliferation-competent hepatocytes in long-term cultures. AAF metabolism proceeded by zero-order kinetics. Hepatocytes processed significant amounts of procarcinogen (≈12 μg AAF/106cells/day). Five ring-hydroxylated and one deacylated species of AAF were secreted into the culture media. Extracellular metabolite levels varied during the growth cycle (days 0-13), but their rank quantitative order was time invariant: 5-OH-AAF > 7-OH-AAF > 3-OH-AAF > N-OH-AAF > aminofluorene (AF) > 1-OH-AAF. Lineweaver-Burk analyses revealed two principal classes of metabolism: System I (high-affinity and low-velocity), Km[APPARENT]= 1.64 × 10−7M and VMAX[APPARENT]= 0.1 nmols/106cells/day; and, System II (low-affinity and high-velocity), Km[APPARENT]= 3.25 × 10−5M and VMAX[APPARENT]= 1000 nmols/106cells/day. A third system of metabolism of AAF to AF, with Km[APPARENT]and VMAX[APPARENT]constants of 9.6 × 10−5M and 4.7 nmols/106cells/day, was also observed. Evidence provided in this report and its companion paper suggests selective roles and intracellular locations for System I- and System II-mediated AAF metabolite formation during hepatocarcinogenesis, although some of the molecules and mechanisms responsible for multi-system processing remain to be fully defined.
Characterization of a Novel Model of Overuse-Induced Calcific Achilles Tendinopathy in Mice: Contralateral Tendinopathy Following Unilateral Tenotomy
Authors: Wang Liang , Zhang Jie , Yin Gang-hui , Zhang Zhong-min , Chen Tian-yu , Jin Jian , Lai Ping-lin , Huang Bin , Yan Bo , Chen Yu-hui , Jin Da-di , Huang Min-jun
Published: October 2017

Objective

To develop a simple but reproducible overuse induced animal model of Achilles tendinopathy in mice for better understanding the underlying mechanism and prevention of calcific Achilles tendinopathy.

Methods

80 C57/B6 mice (8-9 weeks old) were employed and randomly divided into control group and experimental group. Unilateral Achilles tenotomy was performed on the right hindlimb of experiment group. After 12 weeks, the onset of Achilles tedinopathy in the contralateral Achilles tendon was determined by radiological assessment, histological analysis, electron microscopy observation and biomechanical test.

Results

The onset of calcific Achilles tendinopathy in contralateral Achilles tendon was confirmed after 12 weeks unilateral tenotomy. The contralateral Achilles tendon of experimental group was characterized as hypercelluarity, neovascularization and fused collagen fiber disarrangement, compared to the control group. Importantly, intratendon endochondral ossification and calcaneus deformity was featured in contralateral Achilles tendon. Additionally, poor biomechanical properties in the contralateral Achilles tendon revealed the incidence of Achilles tedinopathy.

Conclusion

We hereby introduce a novel simple but reproducible spontaneous contralateral calcific Achilles tendinopathy model in mice, which represents the overuse conditions during the tendinopathy development in human-beings. It should be a useful tool to further study the underlying pathogenesis of calcific Achilles tendinopathy.
Marine cyanolichens from different littoral zones are associated with distinct bacterial communities
Authors: West Nyree J. , Parrot Delphine , Fayet Claire , Grube Martin , Tomasi Sophie , Suzuki Marcelino T.
Published: October 2017

The microbial diversity and function of terrestrial lichens has been well studied, but knowledge about the non-photosynthetic bacteria associated with marine lichens is still scarce. 16S rRNA gene Illumina sequencing was used to assess the culture-independent bacterial diversity in the strictly marine cyanolichen speciesLichina pygmaeaandLichina confinis, and the maritime chlorolichen speciesXanthoria aureolawhich occupy different areas on the littoral zone. Inland terrestrial cyanolichens from Austria were also analysed as for the marine lichens to examine further the impact of habitat/lichen species on the associated bacterial communities. TheL. confinisandL. pygmaeacommunities were significantly different from those of the maritimeXanthoria aureolalichen found higher up on the littoral zone and these latter communities were more similar to those of the inland terrestrial lichens. The strictly marine lichens were dominated by the Bacteroidetes phylum accounting for 50% of the sequences, whereas Alphaproteobacteria, notablySphingomonas, dominated the maritime and the inland terrestrial lichens. Bacterial communities associated with the twoLichinaspecies were significantly different sharing only 33 core OTUs, half of which were affiliated to the Bacteroidetes generaRubricoccus, TunicatimonasandLewinella, suggesting an important role of these species in the marineLichinalichen symbiosis. Marine cyanolichens showed a higher abundance of OTUs likely affiliated to moderately thermophilic and/or radiation resistant bacteria belonging to the Phyla Chloroflexi, Thermi, and the families Rhodothermaceae and Rubrobacteraceae when compared to those of inland terrestrial lichens. This most likely reflects the exposed and highly variable conditions to which they are subjected daily.
Preovulatory oocyte aging in mice affects fertilization rate and embryonic genome activation
Authors: Demond Hannah , Dankert Debora , Grümmer Ruth , Horsthemke Bernhard
Published: October 2017

Delayed ovulation, or preovulatory aging, can seriously compromise the developmental competence of oocytes. In the present study, we have investigated the effect of preovulatory aging on preimplantation embryos. Delaying ovulation with the gonadotropin releasing hormone (GnRH) antagonist Cetrorelix led to a decline in 2-cell rate from 76 to 46%. From control mice, an average of 17 embryos per mouse was retrieved. This number decreased to a mean of 5 embryos per mouse after preovulatory aging, suggesting that fertilization is impaired by aging. For analysis of zygotic genome activation, 2-cell embryos were incubated with BrUTP, which was incorporated into nascent RNA and detected by immunohistochemistry. A 2.85-fold increase in fluorescence intensity was detected after aging, pointing to a precocious activation of the genome. A possible effect of preovulatory aging on genomic imprint maintenance was investigated at the 8-cell stage. Deep amplicon bisulfite sequencing ofIgf2r,Snrpn,H19andPou5f1showed no significant changes between embryos derived from preovulatory-aged oocytes and control embryos, indicating stable imprint maintenance throughout epigenetic reprogramming. We conclude that preovulatory aging of the oocyte affects fertilization and embryonic genomic activation.
Robust identification of deletions in exome and genome sequence data based on clustering of Mendelian errors
Authors: Manheimer Kathryn B. , Patel Nihir , Richter Felix , Gorham Joshua , Tai Angela C. , Homsy Jason , Boskovski Marko T. , Parfenov Michael , Goldmuntz Elizabeth , Chung Wendy K. , Brueckner Martina , Tristani-Firouzi Martin , Srivastava Deepak , Seidman Jonathan G. , Seidman Christine E. , Gelb Bruce D. , Sharp Andrew J.
Published: October 2017

Multiple tools have been developed to identify copy number variants (CNVs) from whole exome (WES) and whole genome sequencing (WGS) data. Current tools such as XHMM for WES and CNVnator for WGS identify CNVs based on changes in read depth. For WGS, other methods to identify CNVs include utilizing discordant read pairs and split reads and genome-wide local assembly with tools such as Lumpy and SvABA, respectively. Here, we introduce a new method to identify deletion CNVs from WES and WGS trio data based on the clustering of Mendelian errors (MEs). Using our Mendelian Error Method (MEM), we identified 127 deletions (inherited and de novo) in 2,601 WES trios from the Pediatric Cardiac Genomics Consortium, with a validation rate of 88% by digital droplet PCR. MEM identified additional de novo deletions compared to XHMM, and also identified sample switches, DNA contamination, a significant enrichment of 15q11.2 deletions compared to controls and eight cases of uniparental disomy. We applied MEM to WGS data from the Genome In A Bottle Ashkenazi trio and identified deletions with 97% specificity. MEM provides a robust, computationally inexpensive method for identifying deletions, and an orthogonal approach for verifying deletions called by other tools.
mobsim: An R package for the simulation and measurement of biodiversity across spatial scales
Authors: May Felix , Gerstner Katharina , McGlinn Dan , Xiao Xiao , Chase Jonathan M.
Published: October 2017

1. Estimating biodiversity and its changes in space and time poses serious methodological challenges. First, there has been a long debate on how to quantify biodiversity, and second, measurements of biodiversity change are scale-dependent. Therefore comparisons of biodiversity metrics between communities are ideally carried out across scales. Simulation can be used to study the utility of biodiversity metrics across scales, but most approaches are system specific and plagued by large parameter spaces and therefore cumbersome to use and interpret. However, realistic spatial biodiversity patterns can be generated without reference to ecological processes, which suggests a simple simulation framework could provide an important tool for ecologists.

2. Here, we present the R package mobsim that allows users to simulate the abundances and the spatial distribution of individuals of different species. Users can define key properties of communities, including the total numbers of individuals and species, the relative abundance distribution, and the degree of spatial aggregation. Furthermore, the package provides functions that derive biodiversity patterns from simulated communities, or from observed data, as well as functions that simulate different sampling designs.

3. We show several example applications of the package. First, we illustrate how species rarefaction and accumulation curves can be used to disentangle changes in the fundamental biodiversity components: (i) total abundance, (ii) relative abundance distribution, (iii) and species aggregation. Second, we demonstrate how mobsim can be used to assess the performance of species-richness estimators. The latter indicates how spatial aggregation challenges classical non-spatial species-richness estimators.

4. mobsim allows the simulation and analysis of a large range of biodiversity scenarios and sampling designs in an efficient and comprehensive way. The simplicity and control provided by the package can also make it a useful didactic tool. The combination of controlled simulations and their analysis will facilitate a more rigorous interpretation of real world data that exhibit sampling effects and scale-dependence.
Structural robustness of mammalian transcription factor networks reveals plasticity across development
Authors: Caldu-Primo JL , Alvarez-Buylla ER , Davila-Velderrain J
Published: October 2017

Network biology aims to understand cell behavior through the analysis of underlying complex biomolecular networks. Inference of condition-specific interaction networks from epigenomic data enables the characterization of the structural plasticity that regulatory networks can acquire in different tissues of the same organism. From this perspective, uncovering specific patterns of variation by comparing network structure among tissues could provide insights into systems-level mechanisms underlying cell behavior. Following this idea, here we propose an empirical framework to analyze mammalian tissue-specific networks, focusing on characterizing and contrasting their structure and behavior in response to perturbations. We structurally represent the state of the cell/tissue by condition specific transcription factor networks generated using chromatin accessibility data, and we profile their systems behavior in terms of the structural robustness against random and directed perturbations. Using this framework, we unveil the structural heterogeneity existing among tissues at different levels of differentiation. We uncover a novel and conserved systems property of regulatory networks underlying embryonic stem cells (ESCs): in contrast to terminally differentiated tissues, the promiscuous regulatory connectivity of ESCs produces a globally homogeneous network resulting in increased structural robustness. Possible biological consequences of this property are discussed.
A physical model of cell metabolism
Authors: Fernandez-de-Cossio-Diaz Jorge , Vazquez Alexei
Published: October 2017

Cell metabolism is characterized by three fundamental energy demands to sustain cell maintenance, to trigger aerobic fermentation and to achieve maximum metabolic rate. Here we report a physical model of cell metabolism that explains the origin of these three energy scales. Our key hypothesis is that the maintenance energy demand is rooted on the energy expended by molecular motors to fluidize the cytoplasm and counteract molecular crowding. Using this model and independent parameter estimates we make predictions for the three energy scales that are in quantitative agreement with experimental values. The model also recapitulates the dependencies of cell growth with extracellular osmolarity and temperature. This theory brings together biophysics and cell biology in a tractable model that can be applied to understand key principles of cell metabolism.
A modified sequence capture approach allowing standard and methylation analyses of the same enriched genomic DNA sample
Authors: Olohan Lisa , Gardiner Laura-Jayne , Lucaci Anita , Steuernagel Burkhard , Wulff Brande , Kenny John , Hall Neil , Hall Anthony
Published: October 2017

Background

Bread wheat has a large complex genome that makes whole genome resequencing costly. Therefore, genome complexity reduction techniques such as sequence capture make re-sequencing cost effective. With a high-quality draft wheat genome now available it is possible to design capture probe sets and to use them to accurately genotype and anchor SNPs to the genome. Furthermore, in addition to genetic variation, epigenetic variation provides a source of natural variation contributing to changes in gene expression and phenotype that can be profiled at the base pair level using sequence capture coupled with bisulphite treatment. Here, we present a new 12 Mbp wheat capture probe set, that allows both the profiling of genotype and methylation from the same DNA sample. Furthermore, we present a method, based on Agilent SureSelect Methyl-Seq, that will use a single capture assay as a starting point to allow both DNA sequencing and methyl-seq.

Results

Our method uses a single capture assay that is sequentially split and used for both DNA sequencing and methyl-seq. The resultant genotype and epi-type data is highly comparable in terms of coverage and SNP/methylation site identification to that generated from separate captures for DNA sequencing and methyl-seq. Furthermore, by defining SNP frequencies in a diverse landrace from the Watkins collection we highlight the importance of having genotype data to prevent false positive methylation calls. Finally, we present the design of a new 12 Mbp wheat capture and demonstrate its successful application to re-sequence wheat.

Conclusion

We present a cost-effective method for performing both DNA sequencing and methyl-seq from a single capture reaction thus reducing reagent costs, sample preparation time and DNA requirements for these complementary analyses.
The DEAD box RNA helicase Ddx39a is essential for myocyte and lens development in zebrafish
Authors: Zhang Linlin , Li Beibei , Yang Yuxi , Scott Ian C. , Lou Xin
Published: October 2017

RNA helicases from the DEAD-box family are found in almost all organisms and have important roles in RNA metabolism including RNA synthesis, processing and degradation. The function and mechanism of action of most of these helicases in animal development and human disease are largely unexplored. In a zebrafish mutagenesis screen to identify genes essential for heart development we identified a zebrafish mutant, which disrupts the gene encoding the RNA helicase DEAD-box 39a (ddx39a).Homozygous ddx39a mutant embryos exhibit profound cardiac and trunk muscle dystrophy, along with lens abnormalities caused by abrupt terminal differentiation of cardiomyocyte, myoblast and lens fiber cells. Further investigation indicated that loss of ddx39a hindered mRNA splicing of members of the kmt2 gene family, leading to mis-regulation of structural gene expression in cardiomyocyte, myoblast and lens fiber cells. Taken together, these results show that Ddx39a plays an essential role in establishment of proper epigenetic status during cell differentiation.
Unbiased association and expression studies identify novel genes for tooth development
Authors: Williams Meredith A. , Biguetti Claudia , Romero-Bustillos Miguel , Maheshwari Kanwal , Dinckan Nuriye , Cavalla Franco , Liu Xiaoming , Silva Renato , Akyalcin Sercan , Uyguner Z Oya , Vieira Alexandre R. , Amendt Brad A. , Fakhrouri Walid D , Letra Ariadne
Published: October 2017

Previously reported co-occurrence of colorectal cancer (CRC) and tooth agenesis (TA) and the overlap in disease-associated gene variants suggest involvement of similar molecular pathways. In this study, we took an unbiased approach and tested genome-wide significant CRC-associated variants for association with isolated TA. Thirty single nucleotide variants (SNVs) in CRC-predisposing genes/loci were genotyped in a discovery dataset composed of 440 individuals with and without isolated TA. Genome-wide significant associations were found between TA andDUSP10rs6687758 (P=1.25 × 10−9) andATF1rs11169552 (P=4.36 × 10−10), with strong association found withCASC8rs10505477 (P=8.2 × 10−5). Additional CRC marker haplotypes were also significantly associated with TA (P<0.0002). Genotyping an independent dataset consisting of 52 cases with TA and 427 controls confirmed the association withCASC8.

Atf1 and Dusp10 expression was detected in the mouse developing teeth from early bud stages to the formation of the complete tooth, suggesting a potential role for these genes and their encoded proteins in tooth development. Our findings suggest Atf1 and Dusp10 as new tooth development genes, while having a role in colorectal cancer. While their individual contributions in tooth development remain to be elucidated, these genes may be considered additional candidates to be tested in future human genetic studies.
Cantu syndrome-associated SUR2 (ABCC9) mutations in distinct structural domains result in KATP channel gain-of-function by differential mechanisms
Authors: McClenaghan Conor , Hanson Alex , Sala-Rabanal Monica , Roessler Helen I. , Josifova Dragana , Grange Dorothy K. , Haaften Gijs van , Nichols Colin G.
Published: October 2017

The complex cardiovascular disorder Cantu Syndrome arises from gain-of-function mutations in either KCNJ8 or ABCC9, the genes encoding the Kir6.1 and SUR2 subunits of ATP-sensitive potassium (KATP) channels. Recent reports indicate that such mutations can increase channel activity by multiple molecular mechanisms. In this study, we determine the mechanism by which KATP function is altered by several mutations in distinct structural domains of SUR2: D207E in the intracellular L0-linker and Y985S, G989E, M1060I, and R1154Q/W in TMD2. Mutations were engineered at their equivalent position in rat SUR2A (D207E, Y981S, G985E, M1056I and R1150Q/W) and functional effects were investigated using macroscopic rubidium (86Rb+) efflux assays and patch clamp electrophysiology. The results show that D207E increases KATP activity by increasing intrinsic stability of the open state, whilst the cluster of Y981S/G985E/M1056I mutations, as well as R1150Q/W, augment Mg-nucleotide activation. The response of mutant channels to inhibition by the sulfonylurea drug glibenclamide, a potential pharmacotherapy for CS, was also tested. There was no major effect on glibenclamide sensitivity for the D207E, Y981S, G985E or M1056I mutations, but glutamine and tryptophan substitution at R1150 resulted in significant decreases in potency.
Deep sequencing of natural and experimental populations of Drosophila melanogaster reveals biases in the spectrum of new mutations
Authors: Assaf Zoe June , Tilk Susanne , Park Jane , Siegal Mark L. , Petrov Dmitri A.
Published: October 2017

Mutations provide the raw material of evolution, and thus our ability to study evolution depends fundamentally on having precise measurements of mutational rates and patterns. We generate a data set for this purpose using (1) de novo mutations from mutation accumulation experiments and (2) extremely rare polymorphisms from natural populations. The first, mutation accumulation (MA) lines are the product of maintaining flies in tiny populations for many generations, therefore rendering natural selection ineffective and allowing new mutations to accrue in the genome. The second, rare genetic variation from natural populations allows the study of mutation because extremely rare polymorphisms are relatively unaffected by the filter of natural selection. We use both methods in Drosophila melanogaster, first generating our own novel data set of sequenced MA lines and performing a meta-analysis of all published MA mutations (∼2000 events) and then identifying a high quality set of ∼70,000 extremely rare (≤0.1%) polymorphisms that are fully validated with resequencing. We use these data sets to precisely measure mutational rates and patterns. Highlights of our results include: a high rate of multinucleotide mutation events at both short (∼5 bp) and long (∼1 kb) genomic distances, showing that mutation drives GC content lower in already GC-poor regions, and using our precise context-dependent mutation rates to predict long-term evolutionary patterns at synonymous sites. We also show that de novo mutations from independent MA experiments display similar patterns of single nucleotide mutation and well match the patterns of mutation found in natural populations.
The potential of hexatungstotellurate(VI) to induce a significant entropic gain during protein crystallization
Authors: Molitor Christian , Bijelic Aleksandar , Rompel Annette
Published: October 2017

The limiting factor in protein crystallography is still the production of high-quality crystals. In this regard, the authors have recently introduced hexatungstotellurate(VI) (TEW) as a new crystallization additive, which proved to be successful within the liquid–liquid phase separation (LLPS) zone. Presented here are comparative crystal structure analyses revealing that protein–TEW binding not only induces and stabilizes crystal contacts, but also exhibits a significant impact on the solvent-driven crystallization entropy, which is the driving force for the crystallization process. Upon the formation of TEW-mediated protein–protein contacts, the release of water molecules from the hydration shells of both molecules,i.e.TEW and the protein, causes a reduced solvent-accessible surface area, leading to a significant gain in solvent entropy. Based on the crystal structures of aurone synthase (in the presence and absence of TEW), insights have also been provided into the formation of a metastable LLPS, which is caused by the formation of protein clusters, representing an ideal starting point in protein crystallization. The results strongly encourage the classification of TEW as a valuable crystallization additive.
Thermomechanical effect in molecular crystals: the role of halogen-bonding interactions
Authors: Mittapalli Sudhir , Perumalla D. Sravanakumar , Nanubolu Jagadeesh Babu , Nangia Ashwini
Published: October 2017

The design and synthesis of mechanically responsive materials is interesting because they are potential candidates to convert thermal energy into mechanical work. Reported in this paper are thermosalient effects in a series of halogen derivatives of salinazids. The chloro derivative, with higher electronegativity and a weaker inter-halogen bond strength (Cl...Cl) exhibits an excellent thermal response, whereas the response is weaker in the iodo derivative with stronger I...I halogen bonding. 3,5-Dichlorosalinazid (Compound-A) exists in three polymorphic forms, two room-temperature polymorphs (Forms I and II) and one high-temperature modification (Form III). The transformation of Form I to Form III upon heating at 328–333 K is a reversible thermosalient transition, whereas the transformation of Form II to Form III is irreversible and non-thermosalient. 3,5-Dibromo- (Compound-B) and 3-bromo-5-chloro- (Compound-C) salinazid are both dimorphic: the Form I to Form II transition in Compound-B is irreversible, whereas Compound-C shows a reversible thermosalient effect (362–365 K). In the case of 3,5-diiodosalinazid (Compound-D) and 3,5-difluorosalinazid (Compound-E), no phase transitions or thermal effects were observed. The thermosalient behaviour of these halosalinazid molecular crystals is understood from the anisotropy in the cell parameters (an increase in theaaxis and a decrease in thebandcaxes upon heating) and the sudden release of accumulated strain during the phase transition. The di-halogen salinazid derivatives (chlorine to iodine) show a decrease in thermal effects with an increase in halogen-bond strength. Interestingly, Compound-B shows solid-state photochromism in its polymorphs along with the thermosalient effect, wherein Form I is cyan and Form II is light orange.
The extended Zintl–Klemm concept, ionic strength I and assessment of the relative stability of lattices using the stability enhancement ratio S
Authors: Jenkins Harry D. Brooke , Vegas Angel
Published: October 2017

This article examines the comparison between the classical formulations used to describe silicates and that derived from the application of the extended Zintl–Klemm concept (EZKC). The ionic strength, I, for 25 silicate lattices is calculated taking into account both formulations, and the results show that, in every single one of the examples, the ionic strength of the Zintl polyanion is higher than that of the classical model which assigns a formal charge of 4+ for silicon. Our earlier study, firstly applied to the germanate (NH4)2Ge[6][Ge[4]
6O15] [Vegas & Jenkins (2017). Acta Cryst. B73, 94–100] and to the polyanion [Ge[4]
6O15]6− equivalent to the pseudo-As2O5 derived from it, explained satisfactorily the charge transfer that takes place in the Zintl compounds. The value of I = ½∑nizi

2 for the Zintl polyanion was greater than for the compound as formulated in the classical way. In that article, a meaningful relationship was found between the electron transfers as defined by the EZKC and the ionic strength I of the anion [Ge[4]
6O15]6− ≡ Ψ-As2O5. Because the ionic strength, I, of a lattice is directly proportional to the lattice potential energy, U
POT, the higher the I the greater the U
POT; thus it is harder to break up the lattice into its constituent ions and hence the lattice itself is more stable, giving support to the idea that the application of the EZKC and the resulting electron shifts yields structures which are inherently thermodynamically more stable than the starting configuration.
(3-Hydroxypiperidin-1-yl)(4-methylphenyl)methanone
Authors: Gomathi S. , Reuben Jonathan D. , Mohamooda Sumaya U. , Dravida Thendral E. R. A. , Usha G.
Published: October 2017

In the title molecule, C13H17NO2, the piperidine ring assumes a chair conformation. The dihedral angle between the mean plane of the piperidine ring and the benzene ring is 45.49 (1)°. In the crystal, molecules are linked by O—H...O intermolecular hydrogen bonds, leading to a molecular chain running along thec-axis direction. The atoms of the hydroxy piperidine ring and the methyl group of methylphenyl ring are disordered over two sets of sites with refined occupancies of 0.754 (5) and 0.246 (5).
3-Methyl-5,5-diphenylimidazolidine-2,4-dione
Authors: Guerrab Walid , Akrad Rachida , Ansar Mhammed , Taoufik Jamal , Mague Joel T. , Ramli Youssef
Published: October 2017

In the title molecule, C16H14N2O2, the imidazolidine-2,4-dione ring carries two phenyl substituents at the 5-position inclined to the five-membered ring plane by 59.17 (6) and 53.21 (6)°. In the crystal, the molecules form chains parallel to thea-axis direction through N—H...O hydrogen bonds. These chains are linked into a three-dimensional network of molecules stacked alongathrough C—H...π(ring) interactions.
From mixed embeddedness to transnational mixed embeddedness
Authors: Bagwell Susan
Published: October 2017

Purpose

The purpose of this paper is to investigate the relevance of the mixed embeddedness thesis (Kloosterman, 2010; Rath and Kloosterman, 2002) to businesses with a more transnational mode of operation.

Design/methodology/approach

Interviews with the owner managers of a sample 24 Vietnamese businesses in London were undertaken to develop an understanding of how micro (individual resources: social, financial and cultural/human capital, and history of migration), meso (local, regional and national markets) and macro (politico-institutional) factors in the UK and overseas influenced business development.

Findings

The findings illustrate how business development is influenced not just by the interaction of the local (UK) opportunity structure and the entrepreneur’s resources, as suggested by the mixed embeddedness thesis, but also by institutional regimes, economies and markets in key countries of the diaspora, and the interaction of these. The extent to which new transnational opportunities can be exploited, however, depends on access to the necessary local and transnational forms of capital.

Practical implications

The empirical evidence presented is used to present a re-working of the mixed embeddedness thesis to provide a framework for understanding the drivers of transnational entrepreneurship.

Originality/value

The paper presents new empirical knowledge of transnational activity amongst the UK Vietnamese business community – a little known refugee community. Conceptually, the paper offers a theoretical development of the mixed embeddedness thesis to enable it to provide an explanation of transnational entrepreneurship amongst new migrant communities.
Exploring the evolution of ethnic entrepreneurship: the case of Brazilian immigrants in Florida
Authors: Cruz Eduardo Picanço , Falcao Roberto Pessoa Queiroz , Barreto Cesar Ramos
Published: October 2017

Purpose

The purpose of this paper is to analyze Brazilian entrepreneurial communities in Florida, through the capitals theory approach.

Design/methodology/approach

By adopting a comparative case study approach, the researchers conducted 80 in-depth interviews with Brazilian entrepreneurs in two different communities – Pompano Beach (Miami area) and Orlando, Florida. Data triangulation was performed through interviews with community stakeholders, secondary sources of data and surveys.

Findings

Authors propose a framework of 27 contexts, based on immigrant entrepreneurs’ capital provisions. Evidence points to different evolutionary paths of the two communities of Brazilian immigrants that were compared. Some of these contexts were found in other ethnicities from extant literature, which shows that it might be generalizable to other cases.

Research limitations/implications

The limitations relate to the fact that the comparative study was conducted in one ethnic group. Nevertheless, the paper brings insights to support future studies on immigrant and ethnic entrepreneurship as a building block for future comparative studies on other immigrant communities.

Practical implications

The work presents a guideline for future entrepreneurs in Florida.

Social implications

Implications of practice will arise after further studies in the contexts of economic, human and social capital. The cases of successful immigrant communities enlightened by the capitals theory might be useful to newly born ethnic enclaves.

Originality/value

The originality of the paper lies on the comparison of two entrepreneurial communities of the same ethnicity in Florida, showing different behaviors due to the internal and environmental factors. Moreover, the Brazilian entrepreneur’s particularities add up to the general theory of immigrant or ethnic entrepreneurship.
Health, happiness and your future: using a “men’s group” format to work with homeless men in London
Authors: Thompson Kate , Brown Pippa , Vieira Stephanie
Published: October 2017

Purpose

The purpose of this paper is to describe an intervention with a group of homeless men from the Horn of Africa, service users of the Horn of Africa Health and Wellbeing Project in London. The group was conceived by the second author who noted the presence of significant psychosocial issues for her clients, but equally their reluctance to access mainstream mental health or social care services.

Design/methodology/approach

Designing the group and introducing it to the men involved threw up some challenges which are explored, and the impact of the group on participants is evaluated.

Findings

Overall both the participants and the facilitators evaluated the group positively and it appeared to have led to lasting change for some of the group members, and this is described. The authors argue that this sort of group may be a more acceptable way to work on psychosocial issues than something more directly focused on mental health intervention. The group protocol is outlined along with suggestions for future work in this area.

Originality/value

This intervention represents a creative alternative to more mainstream psychological interventions for homeless or exiled men.
Identifying “best bets” for searching in chemical engineering
Authors: Badia Giovanna
Published: October 2017

Purpose

Performing efficient literature searches and subscribing to the most comprehensive databases for interdisciplinary fields can be challenging since the literature is typically indexed in numerous databases to different extents. Comparing databases will help information professionals make appropriate choices when teaching, literature searching, creating online subject guides, and deciding which databases to renew when faced with fiscal challenges. The purpose of this paper is to compare databases for searching the chemical engineering literature.

Design/methodology/approach

This paper compares journal indexing and search recall across seven databases that cover the chemical engineering literature in order to determine which database and database pair provide the most comprehensive coverage in this area. It also summarizes published, database comparison methods to aid information professionals in undertaking their own comparative assessments.

Findings

SciFinder, Scopus, and Web of Science, listed alphabetically, were the leading databases for searching the chemical engineering literature. SciFinder-Scopus and SciFinder-Web of Science were the top two database pairs. No single database or pair provided 100 percent complete coverage of the literature examined. Searching a second database increased the recall of results by an average of 17.6 percent.

Practical implications

The findings are useful since they identify “best bets” for performing an efficient search of the chemical engineering literature. Information professionals can also use the methods discussed to compare databases for any discipline or search topic.

Originality/value

This paper builds on the previous literature by using a dual approach to compare the coverage of the chemical engineering literature across multiple databases. To the author’s knowledge, comparing databases in the field of chemical engineering has not been reported in the literature thus far.
Bringing out the everyday in everyday information behavior
Authors: Ocepek Melissa G.
Published: October 2017

Purpose

The purpose of this paper is to argue that scholars in the information behavior (IB) field should embrace the theoretical framework of the everyday to explore a more holistic view of IB.

Design/methodology/approach

The paper describes the theory of the everyday and delineates four opportunities offered by scholars of the everyday. The paper concludes with three examples that highlight what a more everyday-focused everyday information behavior might look like.

Findings

The theory of the everyday provides a useful theoretical framework to ground research addressing the everyday world as well as useful concepts for analysis and research methodology.

Originality/value

The theoretical framework of the everyday contributes to IB research by providing a theoretical justification for work addressing everyday life as well as useful concepts for analysis. The paper also outlines the benefits of integrating methods influenced by institutional ethnography, a methodology previously used to address the nuances of the everyday world.