bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small‐molecule auxin inhibitors that target YUCCA are powerful tools for studying auxin function
Authors: Kakei Yusuke , Yamazaki Chiaki , Suzuki Masashi , Nakamura Ayako , Sato Akiko , Ishida Yosuke , Kikuchi Rie , Higashi Shouichi , Kokudo Yumiko , Ishii Takahiro , Soeno Kazuo , Shimada Yukihisa 
Published: September 2015

SummaryAuxin is essential for plant growth and development, this makes it difficult to study the biological function of auxin using auxin‐deficient mutants. Chemical genetics have the potential to overcome this difficulty by temporally reducing the auxin function using inhibitors. Recently, the indole‐3‐pyruvate (IPyA) pathway was suggested to be a major biosynthesis pathway in Arabidopsis thaliana L. for indole‐3‐acetic acid (IAA), the most common member of the auxin family. In this pathway, YUCCA, a flavin‐containing monooxygenase (YUC), catalyzes the last step of conversion from IPyA to IAA. In this study, we screened effective inhibitors, 4‐biphenylboronic acid (BBo) and 4‐phenoxyphenylboronic acid (PPBo), which target YUC. These compounds inhibited the activity of recombinant YUC in vitro, reduced endogenous IAA content, and inhibited primary root elongation and lateral root formation in wild‐type Arabidopsis seedlings. Co‐treatment with IAA reduced the inhibitory effects. Kinetic studies of BBo and PPBo showed that they are competitive inhibitors of the substrate IPyA. Inhibition constants (Ki) of BBo and PPBo were 67 and 56 nm, respectively. In addition, PPBo did not interfere with the auxin response of auxin‐marker genes when it was co‐treated with IAA, suggesting that PPBo is not an inhibitor of auxin sensing or signaling. We propose that these compounds are a class of auxin biosynthesis inhibitors that target YUC. These small molecules are powerful tools for the chemical genetic analysis of auxin function.
Dissecting the contributions of GC content and codon usage to gene expression in the model alga Chlamydomonas reinhardtii
Authors: Barahimipour Rouhollah , Strenkert Daniela , Neupert Juliane , Schroda Michael , Merchant Sabeeha S. , Bock Ralph 
Published: September 2015

SummaryThe efficiency of gene expression in all organisms depends on the nucleotide composition of the coding region. GC content and codon usage are the two key sequence features known to influence gene expression, but the underlying molecular mechanisms are not entirely clear. Here we have determined the relative contributions of GC content and codon usage to the efficiency of nuclear gene expression in the unicellular green alga Chlamydomonas reinhardtii. By comparing gene variants that encode an identical amino acid sequence but differ in their GC content and/or codon usage, we show that codon usage is the key factor determining translational efficiency and, surprisingly, also mRNA stability. By contrast, unfavorable GC content affects gene expression at the level of the chromatin structure by triggering heterochromatinization. We further show that mutant algal strains that permit high‐level transgene expression are less susceptible to epigenetic transgene suppression and do not establish a repressive chromatin structure at the transgenic locus. Our data disentangle the relationship between GC content and codon usage, and suggest simple strategies to overcome the transgene expression problem in Chlamydomonas.
Hepatitis E virus and the safety of plasma products: investigations into the reduction capacity of manufacturing processes
Authors: Farcet Maria R. , Lackner Cornelia , Antoine Gerhard , Rabel Philip O. , Wieser Andreas , Flicker Andreas , Unger Ulrike , Modrof Jens , Kreil Thomas R. 
Published: September 2015

BACKGROUNDHepatitis E virus (HEV) has been transmitted by transfusion of labile blood products and the occasional detection of HEV RNA in plasma pools indicates that HEV viremic donations might enter the manufacturing process of plasma products. To verify the safety margins of plasma products with respect to HEV, virus reduction steps commonly used in their manufacturing processes were investigated for their effectiveness to reduce HEV.STUDY DESIGN AND METHODSDetection methods for HEV removal (by reverse transcription quantitative polymerase chain reaction) and inactivation (using an infectivity assay) were established. Immunoaffinity chromatography and 20‐nm virus filtration for Factor (F)VIII, cold ethanol fractionation, and low‐pH treatment for immunoglobulin, heat treatment for human albumin, and 35‐nm nanofiltration for FVIII inhibitor‐bypassing activity (FEIBA) were investigated for their capacity to reduce HEV or the physicochemically similar viruses feline calicivirus (FCV) and hepatitis A virus (HAV).RESULTSFor FVIII, HEV reduction of 3.9 and more than 3.9 log was demonstrated for immunoaffinity chromatography and 20‐nm nanofiltration, respectively, and the cold ethanol fractionation for immunoglobulin removed more than 3.5 log of HEV, to below the limit of detection (LOD). Heat treatment of human albumin inactivated more than 3.1 log of HEV to below the LOD and 35‐nm nanofiltration removed 4.0 log of HEV from the FEIBA intermediate. The results indicated HAV rather than FCV as the more relevant model virus for HEV.CONCLUSIONSubstantial HEV reduction during processes commonly used in the manufacturing of plasma products was demonstrated, similar to that previously demonstrated for HAV.
β‐Adrenergic modulation of skeletal muscle contraction: key role of excitation–contraction coupling
Authors: Cairns Simeon P. , Borrani Fabio 
Published: September 2015

AbstractOur aim is to describe the acute effects of catecholamines/β‐adrenergic agonists on contraction of non‐fatigued skeletal muscle in animals and humans, and explain the mechanisms involved. Adrenaline/β‐agonists (0.1–30 μm) generally augment peak force across animal species (positive inotropic effect) and abbreviate relaxation of slow‐twitch muscles (positive lusitropic effect). A peak force reduction also occurs in slow‐twitch muscles in some conditions. β2‐Adrenoceptor stimulation activates distinct cyclic AMP‐dependent protein kinases to phosphorylate multiple target proteins. β‐Agonists modulate sarcolemmal processes (increased resting membrane potential and action potential amplitude) via enhanced Na+–K+ pump and Na+–K+–2Cl− cotransporter function, but this does not increase force. Myofibrillar Ca2+ sensitivity and maximum Ca2+‐activated force are unchanged. All force potentiation involves amplified myoplasmic Ca2+ transients consequent to increased Ca2+ release from sarcoplasmic reticulum (SR). This unequivocally requires phosphorylation of SR Ca2+ release channels/ryanodine receptors (RyR1) which sensitize the Ca2+‐induced Ca2+ release mechanism. Enhanced trans‐sarcolemmal Ca2+ influx through phosphorylated voltage‐activated Ca2+ channels contributes to force potentiation in diaphragm and amphibian muscle, but not mammalian limb muscle. Phosphorylation of phospholamban increases SR Ca2+ pump activity in slow‐twitch fibres but does not augment force; this process accelerates relaxation and may depress force. Greater Ca2+ loading of SR may assist force potentiation in fast‐twitch muscle. Some human studies show no significant force potentiation which appears to be related to the β‐agonist concentration used. Indeed high‐dose β‐agonists (∼0.1 μm) enhance SR Ca2+‐release rates, maximum voluntary contraction strength and peak Wingate power in trained humans. The combined findings can explain how adrenaline/β‐agonists influence muscle performance during exercise/stress in humans.
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Interaction between Reverse Transcriptase and Integrase Is Required for Reverse Transcription during HIV-1 Replication
Authors: Tekeste Shewit S. , Wilkinson Thomas A. , Weiner Ethan M. , Xu Xiaowen , Miller Jennifer T. , Le Grice Stuart F. J. , Clubb Robert T. , Chow Samson A. 
Published: September 2015

ABSTRACTHuman immunodeficiency virus type 1 (HIV-1) replication requires reverse transcription of its RNA genome into a double-stranded cDNA copy, which is then integrated into the host cell chromosome. The essential steps of reverse transcription and integration are catalyzed by the viral enzymes reverse transcriptase (RT) and integrase (IN), respectively.In vitro, HIV-1 RT can bind with IN, and the C-terminal domain (CTD) of IN is necessary and sufficient for this binding. To better define the RT-IN interaction, we performed nuclear magnetic resonance (NMR) spectroscopy experiments to map a binding surface on the IN CTD in the presence of RT prebound to a duplex DNA construct that mimics the primer-binding site in the HIV-1 genome. To determine the biological significance of the RT-IN interaction during viral replication, we used the NMR chemical shift mapping information as a guide to introduce single amino acid substitutions of nine different residues on the putative RT-binding surface in the IN CTD. We found that six viral clones bearing such IN substitutions (R231E, W243E, G247E, A248E, V250E, and I251E) were noninfectious. Further analyses of the replication-defective IN mutants indicated that the block in replication took place specifically during early reverse transcription. The recombinant INs purified from these mutants, though retaining enzymatic activities, had diminished ability to bind RT in a cosedimentation assay. The results indicate that the RT-IN interaction is functionally relevant during the reverse transcription step of the HIV-1 life cycle.IMPORTANCETo establish a productive infection, human immunodeficiency virus type 1 (HIV-1) needs to reverse transcribe its RNA genome to create a double-stranded DNA copy and then integrate this viral DNA genome into the chromosome of the host cell. These two essential steps are catalyzed by the HIV-1 enzymes reverse transcriptase (RT) and integrase (IN), respectively. We have shown previously that IN physically interacts with RT, but the importance of this interaction during HIV-1 replication has not been fully characterized. In this study, we have established the biological significance of the HIV-1 RT-IN interaction during the viral life cycle by demonstrating that altering the RT-binding surface on IN disrupts both reverse transcription and viral replication. These findings contribute to our understanding of the RT-IN binding mechanism, as well as indicate that the RT-IN interaction can be exploited as a new antiviral drug target.
Human Cytomegalovirus pUL93 Is Required for Viral Genome Cleavage and Packaging
Authors: DeRussy Bernadette M. , Tandon Ritesh 
Published: September 2015

ABSTRACT
Human cytomegalovirus (HCMV) pUL93 is essential for virus growth, but its precise function in the virus life cycle is unknown. Here, we characterize a UL93 stop mutant virus (UL93st-TB40/E-BAC) to demonstrate that the absence of this protein does not restrict viral gene expression; however, cleavage of viral DNA into unit-length genomes as well as genome packaging is abolished. Thus, pUL93 is required for viral genome cleavage and packaging.
Interplay between the Herpes Simplex Virus 1 gB Cytodomain and the gH Cytotail during Cell-Cell Fusion
Authors: Rogalin Henry B. , Heldwein Ekaterina E. 
Published: September 2015

ABSTRACT
Herpesvirus entry into cells is mediated by the viral fusogen gB, which is thought to refold from the prefusion to the postfusion form in a series of large conformational changes that energetically couple refolding to membrane fusion. In contrast to most viral fusogens, gB requires a conserved heterodimer, gH/gL, as well as other nonconserved proteins. In a further mechanistic twist, gB-mediated cell-cell fusion appears restricted by its intraviral or cytoplasmic domain (cytodomain) because mutations within it result in a hyperfusogenic phenotype. Here, we characterized a panel of hyperfusogenic HSV-1 gB cytodomain mutants and show that they are fully functional in cell-cell fusion at shorter coincubation times and at lower temperatures than those for wild-type (WT) gB, which suggests that these mutations reduce the kinetic energy barrier to fusion. Despite this, the mutants require both gH/gL and gD. We confirm previous observations that the gH cytotail is an essential component of the cell-cell fusion mechanism and show that the N-terminal portion of the gH cytotail is critical for this process. Moreover, the fusion levels achieved by all gB constructs, WT and mutant, were proportionate to the length of the gH cytotail. Putting these results together, we propose that the gH cytotail, in addition to the gH/gL ectodomain, plays an essential role in gB activation, potentially acting as a “wedge” to release the gB cytodomain “clamp” and enable gB activation.

IMPORTANCE
Herpesviruses infect their hosts for life and cause a substantial disease burden. Herpes simplex viruses cause oral and genital sores as well as rare yet severe encephalitis and a panoply of ocular ailments. Infection initiates when the viral envelope fuses with the host cell membrane in a process orchestrated by the viral fusogen gB, assisted by the viral glycoproteins gH, gL, and gD and a cellular gD receptor. This process is more complicated than that of most other viruses and is subject to multiple regulatory inputs. Antiviral and vaccine development would benefit from a detailed mechanistic knowledge of this process and how it is regulated.
Effects of evidence-based prevention training on neuromuscular and biomechanical risk factors for ACL injury in adolescent female athletes: a randomised controlled trial
Authors: Zebis Mette K , Andersen Lars L , Brandt Mikkel , Myklebust Grethe , Bencke Jesper , Lauridsen Hanne Bloch , Bandholm Thomas , Thorborg Kristian , Hölmich Per , Aagaard Per 
Published: September 2015

BackgroundAdolescent female football and handball players are among the athletes with the highest risk of sustaining anterior cruciate ligament (ACL) injuries.AimThis study evaluated the effects of evidence-based lower extremity injury prevention training on neuromuscular and biomechanical risk factors for non-contact ACL injury.Methods40 adolescent female football and handball players (15–16 years) were randomly allocated to a control group (CON, n=20) or neuromuscular training group (NMT, n=20). The NMT group performed an injury prevention programme as a warm-up before their usual training 3 times weekly for 12 weeks. The CON group completed their regular warm-up exercise programme before training. Players were tested while performing a side cutting movement at baseline and 12-week follow-up, using surface electromyography (EMG) and three-dimensional movement analysis. We calculated: (1) EMG amplitude from vastus lateralis (VL), semitendinosus (ST) and biceps femoris 10 ms prior to initial contact (IC) normalised to peak EMG amplitude recorded during maximal voluntary isometric contraction and (2) VL-ST EMG preactivity difference during the 10 ms prior to foot contact (primary outcome). We measured maximal knee joint valgus moment and knee valgus angle at IC.ResultsThere was a difference between groups at follow-up in VL-ST preactivity (43% between-group difference; 95% CI 32% to 55%). No between-group differences were observed for kinematic and kinetic variables.ConclusionsA 12-week injury prevention programme in addition to training and match play in adolescent females altered the pattern of agonist-antagonist muscle preactivity during side cutting. This may represent a more ACL-protective motor strategy.
Glomerular filtration rate (GFR) during and after STEMI: a single-centre, methodological study comparing estimated and measured GFR
Authors: Venetsanos Dimitrios , Alfredsson Joakim , Segelmark Mårten , Swahn Eva , Lawesson Sofia Sederholm 
Published: September 2015

ObjectivesTo validate the performance of the most commonly used formulas for estimation of glomerular filtration rate (GFR) against measured GFR during the index hospitalisation for ST-elevation myocardial infarction (STEMI).SettingSingle centre, methodological study.Participants40 patients with percutaneous coronary intervention-treated STEMI were included between November 2011 and February 2013. Patients on dialysis, cardiogenic shock or known allergy to iodine were excluded.Outcome measuresCreatinine and cystatin C were determined at admission and before discharge in 40 patients with STEMI. Clearance of iohexol was measured (mGFR) before discharge. We evaluated and compared the Cockcroft-Gault (CG), the Modification of Diet in Renal Disease (MDRD-IDMS), the Chronic Kidney Disease Epidemiology (CKD-EPI) and the Grubb relative cystatin C (rG-CystC) with GFR regarding correlation, bias, precision and accuracy (P30). Agreement between eGFR and mGFR to discriminate CKD was assessed by Cohen's κ statistics.ResultsMDRD-IDMS and CKD-EPI demonstrated good performance to estimate GFR (correlation 0.78 vs 0.81%, bias −1.3% vs 1.5%, precision 17.9 vs 17.1 mL/min 1.73 m2and P30 82.5% vs 82.5% for MDRD-IDMS vs CKD-EPI). CKD was best classified by CKD-EPI (κ 0.83). CG showed the worst performance (correlation 0.73%, bias −1% to 3%, precision 22.5 mL/min 1.73 m2and P30 75%). The rG-CystC formula had a marked bias of −17.8% and significantly underestimated mGFR (p=0.03). At arrival, CKD-EPI and rG-CystC had almost perfect agreement in CKD classification (κ=0.87), whereas at discharge agreement was substantially lower (κ=0.59) and showed a significant discrepancy in CKD classification (p=0.02). Median cystatin C concentration increased by 19%.ConclusionsIn acute STEMI, CKD-EPI showed the best CKD-classification ability followed by MDRD-IDMS, whereas CG performed the worst. STEMI altered the performance of the cystatin C equation during the acute phase, suggesting that other factors might be involved in the rise of cystatin C.
Identification of reciprocal causality between non-alcoholic fatty liver disease and metabolic syndrome by a simplified Bayesian network in a Chinese population
Authors: Zhang Yongyuan , Zhang Tao , Zhang Chengqi , Tang Fang , Zhong Nvjuan , Li Hongkai , Song Xinhong , Lin Haiyan , Liu Yanxun , Xue Fuzhong 
Published: September 2015

ObjectivesIt remains unclear whether non-alcoholic fatty liver disease (NAFLD) is a cause or a consequence of metabolic syndrome (MetS). We proposed a simplified Bayesian network (BN) and attempted to confirm their reciprocal causality.SettingBidirectional longitudinal cohorts (subcohorts A and B) were designed and followed up from 2005 to 2011 based on a large-scale health check-up in a Chinese population.ParticipantsSubcohort A (from NAFLD to MetS, n=8426) included the participants with or without NAFLD at baseline to follow-up the incidence of MetS, while subcohort B (from MetS to NAFLD, n=16 110) included the participants with or without MetS at baseline to follow-up the incidence of NAFLD.ResultsIncidence densities were 2.47 and 17.39 per 100 person-years in subcohorts A and B, respectively. Generalised estimating equation analyses demonstrated that NAFLD was a potential causal factor for MetS (relative risk, RR, 95% CI 5.23, 3.50 to 7.81), while MetS was also a factor for NAFLD (2.55, 2.23 to 2.92). A BN with 5 simplification strategies was used for the reciprocal causal inference. The BN's causal inference illustrated that the total effect of NAFLD on MetS (attributable risks, AR%) was 2.49%, while it was 19.92% for MetS on NAFLD. The total effect of NAFLD on MetS components was different, with dyslipidemia having the greatest (AR%, 10.15%), followed by obesity (7.63%), diabetes (3.90%) and hypertension (3.51%). Similar patterns were inferred for MetS components on NAFLD, with obesity having the greatest (16.37%) effect, followed by diabetes (10.85%), dyslipidemia (10.74%) and hypertension (7.36%). Furthermore, the most important causal pathway from NAFLD to MetS was that NAFLD led to elevated GGT, then to MetS components, while the dominant causal pathway from MetS to NAFLD began with dyslipidaemia.ConclusionsThe findings suggest a reciprocal causality between NAFLD and MetS, and the effect of MetS on NAFLD is significantly greater than that of NAFLD on MetS.
Tobacco control policies and perinatal and child health: a systematic review and meta-analysis protocol
Authors: Been Jasper V , Mackenbach Johan P , Millett Christopher , Basu Sanjay , Sheikh Aziz 
Published: September 2015

IntroductionChildren experience considerable morbidity and mortality due to tobacco smoke exposure. Tobacco control policies may benefit child health by reducing this exposure. We aim to comprehensively assess the effects of the range of tobacco control policies advocated by the WHO on perinatal and child health.Methods and analysisWe will systematically search 19 electronic literature databases (from inception) for published studies, and the WHO International Clinical Trials Registry Platform for unpublished studies. Additional work will be identified via handsearching references and citations, and through consulting an international panel of experts. No language restrictions will apply. Following Cochrane Effective Practice and Organisation of Care (EPOC) guidelines, randomised and clinical controlled trials, controlled before-and-after studies, and interrupted time series designs, are eligible. Studies of interest will assess the impact of any of the WHO-advocated tobacco control policies contained in the MPOWER acronym (except ‘Monitoring tobacco use’) on at least one outcome of interest among children aged 0–12 years. The primary outcomes are: perinatal mortality, preterm birth, asthma exacerbations requiring hospital attendance and respiratory infections requiring hospital attendance. Data will be extracted using customised forms and authors will be contacted to obtain missing information. Risk of bias will be assessed using EPOC criteria. Findings will be reported in narrative and tabular form. Between-study heterogeneity will be assessed clinically and statistically using I2. If appropriate and possible, random-effects meta-analysis will be conducted for each unique combination of intervention and outcome. Subgroup analyses will be performed to assess the influence of the comprehensiveness of each policy, and to explore the impact of each policy according to socioeconomic status.Ethics and disseminationNo ethical assessment is necessary as we will summarise existing studies. We will publish our findings in a peer-reviewed scientific journal.Trial registration numberPROSPERO; CRD42015023448.
Risky driving among UK regular armed forces personnel: changes over time
Authors: Sheriff Rebecca J Syed , Forbes Harriet J , Wessely Simon C , Greenberg Neil , Jones Norman , Fertout Mohammed , Harrison Kate , Fear Nicola T 
Published: September 2015

ObjectivesTo compare the prevalence of self-reported risky driving in a sample of UK military personnel at 2 different time points (2004 and 2009), and to identify the incidence of new onset risky driving and possible determinants of becoming a new risky driver.MethodsData were used from 2 phases of a military cohort study investigating the health and well-being of UK military personnel between 2004 and 2009. Participants were included if they were undertaking regular (rather than reserve) engagements, had completed both surveys and reported being a driver at both surveys. Univariable and multivariable logistic regression analyses were performed to examine the relationship between risky driving status and sociodemographic and military characteristics. Data analysis was conducted in 2011.ResultsThe prevalence of risky driving reduced from 18% to 14%, over an average of 3.3 years. The incidence of new onset risky driving was 7%. Predictors for becoming a new risky driver were: younger age, not being in a relationship at phase 2 and harmful alcohol use. Those deployed after 2007 were less likely to become risky drivers following deployment, compared with those deployed before 2007 (adjusted OR 0.62 (95% CI 0.40 to 0.95)).ConclusionsThe prevalence of becoming a risky driver appears to have reduced over time. This paper suggests a number of explanations for this reduction, including changes in the way that the UK military have dealt with road safety with the introduction of the road safety campaign (in 2007).