bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement in left intraventricular pressure gradients after aortic valve replacement in aortic stenosis patients
Authors: Guerra Miguel , Mendes‐Ferreira Pedro , Adão Rui , Pereira Eulália , Vieira Manuela , Lourenço André P. , Brás‐Silva Carmen , Bastos Pedro , Vouga Luís , Leite‐Moreira Adelino F.
Published: February 2017

New Findings

What is the central question of this study?

Normal diastolic and systolic intraventricular pressure gradients are decreased when left ventricular filling and/or emptying are compromised. We hypothesized that in patients with severe aortic valve stenosis, a condition that interferes with ventricular filling and emptying, those gradients would be disturbed.

What is the main finding and its importance?

We showed the existence of intraventricular pressure gradients throughout the cardiac cycle in the human left ventricle. Moreover, we demonstrated, for the first time, that diastolic and systolic gradients, which are markers of normal ventricular filling and emptying, respectively, improved in patients with severe aortic valve stenosis immediately after valve replacement.

The present study was conducted to characterize left intraventicular pressure gradients, which are markers of normal cardiac function, in patients with severe aortic stenosis, a condition that interferes with ventricular filling and emptying. In 10 patients (four male; mean age 71.3 ± 4.8 years old) undergoing aortic valve replacement, two high‐fidelity pressure catheters were inserted inside the cavity of the left ventricle through an apical puncture and positioned in the apex and outflow tract below the aortic valve. Pressures were continuously acquired and gradients calculated as apical minus outflow tract pressure, before and immediately after aortic valve replacement. During early filling, we recorded a negative intraventricular gradient along the basal portion of the left ventricle in the apical direction (−0.82 ± 0.45 mmHg), which increased to −3.97 ± 0.42 mmHg after aortic valve replacement. In late filling, intraventricular flow was now directed towards the outflow tract, with a positive pressure gradient both before (+1.23 ± 0.37 mmHg) and after surgery (+2.12 ± 0.58 mmHg). During systole, before surgery we observed a positive pressure gradient between the apex and outflow tract during both rapid (+1.60 ± 0.21 mmHg) and slow ejection phases (+1.68 ± 0.12 mmHg), whereas after aortic valve replacement the positive gradient (+1.54 ± 0.15 mmHg) during rapid ejection was inverted (−3.92 ± 0.34 mmHg) during the slow ejection phase. We demonstrated that in patients with severe aortic stenosis both diastolic and systolic intraventricular pressure gradients are significantly attenuated but can be restored immediately after aortic valve replacement. The assessment and measurement of intraventricular pressure gradients and their modulation in pathophysiological conditions may provide novel insights into cardiac physiology.
Fetal adaptations in insulin secretion result from high catecholamines during placental insufficiency
Authors: Limesand Sean W. , Rozance Paul J.
Published: February 2017

Placental insufficiency and intrauterine growth restriction (IUGR) of the fetus affects approximately 8% of all pregnancies and is associated with short‐ and long‐term disturbances in metabolism. In pregnant sheep, experimental models with a small, defective placenta that restricts delivery of nutrients and oxygen to the fetus result in IUGR. Low blood oxygen concentrations increase fetal plasma catecholamine concentrations, which lower fetal insulin concentrations. All of these observations in sheep models with placental insufficiency are consistent with cases of human IUGR. We propose that sustained high catecholamine concentrations observed in the IUGR fetus produce developmental adaptations in pancreatic β‐cells that impair fetal insulin secretion. Experimental evidence supporting this hypothesis shows that chronic elevation in circulating catecholamines in IUGR fetuses persistently inhibits insulin concentrations and secretion. Elevated catecholamines also allow for maintenance of a normal fetal basal metabolic rate despite low fetal insulin and glucose concentrations while suppressing fetal growth. Importantly, a compensatory augmentation in insulin secretion occurs following inhibition or cessation of catecholamine signalling in IUGR fetuses. This finding has been replicated in normally grown sheep fetuses following a 7‐day noradrenaline (norepinephrine) infusion. Together, these programmed effects will potentially create an imbalance between insulin secretion and insulin‐stimulated glucose utilization in the neonate which probably explains the transient hyperinsulinism and hypoglycaemia in some IUGR infants.

image
Magnetohydrodynamic CuO–Water Nanofluid in a Porous Complex-Shaped Enclosure
Authors: Sheikholeslami M. , Rokni Houman B.
Published: February 2017

Steady nanofluid convective flow in a porous cavity is investigated. Darcy and Koo–Kleinstreuer–Li (KKL) models are considered for porous media and nanofluid, respectively. The solutions of final equations are obtained by control volume-based finite element method (CVFEM). Effective parameters are CuO–water volume fraction, number of undulations, and Rayleigh and Hartmann numbers for porous medium. A correlation for Nuave is presented. Results depicted that heat transfer improvement reduces with the rise of buoyancy forces. Influence of adding nanoparticle augments with augment of Lorentz forces. Increasing Hartmann number leads to decrease in temperature gradient.
Fatigue Performance Evaluations of Vehicle Toroidal Liquefied Petroleum Gas Fuel Tanks
Authors: Kartal Fuat , Kisioglu Yasin
Published: February 2017

In this study, fatigue performances of the vehicle toroidal liquefied petroleum gas (LPG) fuel tanks were examined to estimate the fatigue life and its failure locations using both experimental and finite element analysis (FEA) methods. The experimental investigations performed as accelerated fatigue tests were carried out using a hydraulics test unit in which the tanks were internally pressurized by hydraulic oil. The LPG tanks were subjected to repeated cyclic pressure load varying from zero to service pressure (SP) of the tank. The computerized FEA modeling of these tanks were developed in three-dimensional (3D) form using nonuniform geometrical parameters and nonlinear material properties. These models were also subjected to zero-based high cycle fatigue pressure load considering the stress life approach. The FEA modeling process was also simulated in nonhomogeneous material conditions. Therefore, the fatigue life performance and failure location of the toroidal LPG fuel tanks were predicted using the computer-aided simulations and compared with the experimental results.
Ductile Rupture Pressure Prediction for Capped-Open Casing and Tubing Under Combined Loads
Authors: Sun Yongxing , Deng Kuanhai , Lin Yuanhua , Shi Taihe
Published: February 2017

Casing and tubing is widely used as protective conduits during all the phases of operations and productions for the oil and gas industry. Recently, casing and tubing burst failure accidents often take place in high pressure and high temperature (HPHT) oil and gas wells during production. Therefore, it is very important to accurately predict casing and tubing bust strength in the casing and tubing design and operation process. PD CEN ISO-TR 10400 presents the ductile rupture model for capped-end conditions, but capped-end casing and tubing applied in oil fields is few. For this case, this document establishes the ductile rupture model for capped-open conditions under combined loads on the base of PD CEN ISO-TR 10400. Numerical and experimental comparisons show that the ductile rupture model for capped-open conditions under combined loads prediction values essentially coincides with burst data provided by PD CEN ISO-TR 10400.
4.4 Peter Rühmkorf: 'Rotkäppchen und der Wolfspelz'
Authors: -- --
Published: February 2017

Parody Grimm Rühmkorf Rotkäppchen
Vorwort
Authors: Voit Friedrich
Published: February 2017

Vorwort
Kurt Singer - Karl Wolfskehl - "Der Mensch ist ein Ganzes, eins in jeder seiner unterschiedlichen Erscheinungen, eins auf jedem seiner unterschiedlichen Wege."
Authors: Schilling Ulrike
Published: February 2017

Wolfskehl
"Von Krieg und Kriegsgeschrei": Fontanes Kriegsdarstellungen im Kontext
Authors: -- --
Published: February 2017

Fontane
"Italian Hours": Theodor Fontane und Henry James in Italien in den 1870er Jahren
Authors: -- --
Published: February 2017

Fontane
Christian Grawe: Veröffentlichungen über Fontane
Authors: -- --
Published: February 2017

Grawe Fontane
I. Teil: Autor und Oeuvre
 Warum Fontane kein Barbarossa-Epos schrieb und andere Vermutungen über den mittleren Fontane
Authors: -- --
Published: February 2017

Fontane
Die Nibelungen und anderes Volk - Fahrten in eine fremde, unheimliche Welt
Authors: Smits Kathryn
Published: February 2017

Nibelungenlied
Statcast and the Baseball Trajectory Calculator
Authors: Kagan David , Nathan Alan M.
Published: February 2017

Baseball’s flirtation with technology began in 2005 when PITCHf/x® by Sportvision started to be installed in major league ballparks. Every stadium had the system operational by 2007. Since then, the trajectories of over six million pitches have been measured to within about half an inch using three 60-Hz video cameras to track the position of the ball.
Conceptualizing Rolling Motion Through an Extreme Case Reasoning Approach
Authors: Hasović Elvedin , Mešić Vanes , Erceg Nataša
Published: February 2017

In this paper we are going to show how learning about some counterintuitive aspects of rolling motion can be facilitated by combining the use of analogies with extreme case reasoning. Specifically, the intuitively comprehensible examples of “rolling” polygonal prisms are used as an analogical anchor that is supposed to help the students develop conceptual understanding about counterintuitive aspects of rolling motion.
A Student-Centered, Inquiry-Based Approach to Young’s Double-Slit Experiment (and Other Investigations of Light’s Wave Character)
Authors: Meyer Daniel Z.
Published: February 2017

Young’s double-slit experiment is one of the most historically significant works in physics, and one that is easily done in an introductory physics class. It is also an excellent example of an investigation that allows us to infer the nature of phenomena beyond direct observation. Unfortunately, perhaps because of this, it is often also an excellent example of the problem with canned cookbook labs. Students dutifully go through the physical motions of the investigation and can easily get good measurements. But actual intellectual engagement is missing. This paper details an instructional sequence that allows an authentic, student-centered approach to this historic investigation. Key to the approach is creating the context in which students can meaningfully devise an investigation into light’s wave character.
Reference equivalent threshold sound pressure levels for Apple EarPods
Authors: Ho Cheng-Yu , Li Pei-Chun , Young Shuenn-Tsong
Published: February 2017

Reference equivalent threshold sound pressure levels (RETSPLs) are used when calibrating audiometric equipment to a hearing threshold level of zero at various frequencies. To the best of the authors' knowledge, the RETSPLs for Apple EarPods (MB770G) have not been reported, and so this study aimed to measure them. The hearing thresholds of 36 normal-hearing subjects (72 ears) were measured at 250, 500, 1000, 2000, 4000, and 8000 Hz, with the measurements being performed twice in 33 subjects (66 ears) for evaluating the test–retest reliability. This study provides Apple EarPod RETSPLs and shows significant Pearson's correlations (p < 0.001) with no significant Wilcoxon signed-rank test differences (p > 0.01), which confirm the test reliability.
Cognitive Appraisal of Sources of Stress Experienced by Elite Male Wheelchair Basketball Players
Authors: Campbell Elizabeth , Jones Graham
Published: February 2017

This is the second in a two-part study that examined how Great Britain male wheelchair basketball players (n = 10) cognitively appraise sources of stress. The first part (Campbell & Jones, 2002) established 10 distinct general stress source dimensions. The second part (reported herein) describes how the players rated each source of stress on challenge, threat, harm, controllability, severity, and frequency. Data was collected by interviews. Five significant positive relationships, ranging from .64 to .71, were shown between the variables: challenge and controllability, harm/loss and threat, threat and severity, harm/loss and severity, and frequency and severity. The findings show the importance of obtaining information about stress source variables if researchers and practitioners are to fully understand the nature of the sources of stress experienced by elite athletes.
Toward an Understanding of Developmental Coordination Disorder
Authors: Henderson Sheila E. , Henderson Leslie
Published: February 2017

We consider three issues concerning unexpected difficulty in the acquisition of motor skills: terminology, diagnosis, and intervention. Our preference for the label Developmental Coordination Disorder (DCD) receives justification. Problems in diagnosis are discussed, especially in relation to the aetiology-dominated medical model. The high degree of overlap between DCD and other childhood disorders appears to militate against its acceptance as a distinct syndrome. In this context, we emphasize the need to determine whether incoordination takes different forms when it occurs alone is combined with general developmental delay or with other specific disorders in children of normal intelligence. Studies of intervention have mostly shown positive effects but do not, as yet, allow adjudication between different sorts of content. We suggest that the study of DCD and its remediation would benefit greatly from the employment of the simple but rich paradigms developed for the experimental analysis of fully formed adult movement skills.
Perceived Competence, Discrepancy Scores, and Global Self-Worth
Authors: Rose Elizabeth , Larkin Dawne
Published: February 2017

According to Harter (1985a), global self-worth (GSW) can be predicted from the relationship between perceptions of competence and importance ratings. In this study, we employed Harter’s (1985b) Importance Rating Scale (IRS) and Self-Perception Profile for Children (SPPC) to examine importance ratings, discrepancy scores, and domain-specific perceptions of competence as predictors of GSW. Children (N = 130, 62 boys and 68 girls) aged 8-12 years were categorized into high (HMC; n = 62) and low motor coordination (LMC; n = 68) groups according to their scores on a motor proficiency battery (McCarron, 1982). Regression analyses using domain-specific perceptions of competence, importance, and discrepancy scores confirmed that self-perception ratings were the best predictors of GSW. For both groups, perceptions of physical appearance, social acceptance, and behavioral conduct contributed significantly to prediction of GSW. By contrast, perceived athletic competence increased prediction of GSW for the HMC group but not the LMC group.
Validating the Physical Educators’ Attitude Toward Teaching Individuals with Disabilities III (PEATID III) Survey for Future Professionals
Authors: Folsom-Meek Sherry L. , Rizzo Terry L.
Published: February 2017

The purpose of this study was to assess validity and reliability of the Physical Educators’ Attitude Toward Teaching Individuals with Disabilities III (PEATID III; Rizzo, 1993) for future professionals. Participants (N = 3,464) were undergraduate students enrolled in the introductory adapted physical education course at 235 colleges and universities. Construct validity was obtained through principal components analysis with oblique rotation and supported by principal components analysis with varimax rotation. Results showed that PEATID III measures three factors: (a) outcomes of teaching students with disabilities in regular classes, (b) effects on student learning, and (c) need for more academic preparation to teach students with disabilities. Reliability, as estimated through coefficient alpha, was .88 for the total scale and .71 or greater for each of the disability subscales.
Comparison of Practicum Types in Changing Preservice Teachers’ Attitudes and Perceived Competence
Authors: Hodge Samuel R. , Davis Ronald , Woodard Rebecca , Sherrill Claudine
Published: February 2017

The purpose was to compare the effects of two practicum types (off campus and on campus) on physical education teacher education (PETE) students’ attitudes and perceived competence toward teaching school-aged students with physical disabilities or moderate-severe mental retardation. PETE students, enrolled in a 15-week introductory adapted physical education (APE) course and involved in eight sessions of either off-campus (n = 22) or on-campus (n = 15) practicum experiences, completed Rizzo’s (1993a) Physical Educators’ Attitudes Toward Teaching Individuals with Disabilities-III (PEATID-III) two times. Analysis of pretest data revealed that groups were equated on gender, experience, attitude, and perceived competence. Kruskal-Wallis ANOVA revealed no significant difference between practicum types on posttest attitude and perceived competence measures. Attitude scores did not differ significantly from pretest to posttest. Perceived competence improved significantly from pretest to posttest under both practicum types. Implications for professional preparation are discussed.
Parents’ Perceptions of Motor Interventions for Infants and Toddlers with Down Syndrome
Authors: Sayers L. Kristi , Cowden Jo E. , Sherrill Claudine
Published: February 2017

The purpose of the study was to analyze parents’ perceptions of their participation in a university-directed, parent-implemented, home-based pediatric strength intervention program as (a) one approach to evaluating the effectiveness of a program conducted over a 4-year period with families of infants and toddlers with Down syndrome and (b) a means of deriving guidelines for future early intervention programs. Participants were 22 parents from 11 families of children with Down syndrome; the children ranged in age from 6 to 42 months. Participatory evaluation research, semistructured audio recorded home interviews, and qualitative content analysis were used. The results indicated that the parents (a) perceived themselves as being empowered to implement the program, (b) perceived their expectations about improved motor development of their children had been met, and (c) perceived the program was worthwhile. The parents’ perceptions provided meaningful evaluation data that enabled the development of guidelines for future pediatric strength intervention programs.
Taxonomic Theory and the ICF: Foundations for a Unified Disability Athletics Classification
Authors: Tweedy Sean M.
Published: February 2017

Development of a unified classification system to replace four of the systems currently used in disability athletics (i.e., track and field) has been widely advocated. The definition and purpose of classification, underpinned by taxonomic principles and collectively endorsed by relevant disability sport organizations, have not been developed but are required for successful implementation of a unified system. It is posited that the International classification of functioning, disability, and health (ICF), published by the World Health Organization (2001), and current disability athletics systems are, fundamentally, classifications of the functioning and disability associated with health conditions and are highly interrelated. A rationale for basing a unified disability athletics system on ICF is established. Following taxonomic analysis of the current systems, the definition and purpose of a unified disability athletics classification are proposed and discussed. The proposed taxonomic framework and definitions have implications for other disability sport classification systems.
An Evaluative Case Study of a Psychological Skills Training Program for Athletes with Intellectual Disabilities
Authors: Gorely Trish , Jobling Anne , Lewis Kellie , Bruce David
Published: February 2017

The purpose was to develop an evaluative case study of six 3-hr sessions, spaced over 3 months, of psychological skills training (PST) provided to athletes with an intellectual disability who were training for the Basketball Australia State Championships. Participants were 7 males and 7 females, aged 15.8 to 27.1 years, with a receptive language level of 7 to 13.7 years, 2 female coaches, 2 psychologists, and 1 registered psychologist supervisor. Sessions focused specifically on stress management, with primary attention given to cue words, breathing techniques, and positive thinking. Findings, based on interviews and participant observations, revealed that all participants believed that the PST was appropriate and worthwhile.
Gait Pattern Classification of Children with Developmental Coordination Disorder
Authors: Woodruff Sarah J. , Bothwell-Myers Connie , Tingley Maureen , Albert Wayne J.
Published: February 2017

The purpose was to develop an index of walking performance and to examine gait pattern classifications of children with developmental coordination disorder (DCD). The San Diego database (Sutherland, Olshen, Biden, & Wyatt, 1988) provided data for our calculation of the index and for determining that the index was able to differentiate between gait variables of older (ages 3 to 7) and younger (ages 1 to 2.5) children comprising the database. We obtained cinematographical data on 17 biomechanical markers of 6 boys and 1 girl, ages 6 to 7, with DCD, during walking. Analysis of individuals with DCD gait patterns revealed that most had abnormal walking patterns. The means of the time/distance gait variables did not differ between children with DCD and San Diego children, ages 3 to 7. Children with DCD had much larger variances than other children, indicating no systematic pattern in individual gait differences.
Construct Validity of the Test of Gross Motor Development: A Cross-Validation Approach
Authors: Evaggelinou Christina , Tsigilis Nikolaos , Papa Areti
Published: February 2017

This study was designed to examine the underlying structure of the Test of Gross Motor Development (TGMD) in Ulrich (1985). The TGMD was administered to 644 children who were randomly divided into two groups (calibration group and validation group). The calibration group (n = 324) included 150 boys and 174 girls, and the validation group included 160 boys and 160 girls, ranging from 3 to 10 years. A two-factor model was postulated and supported. According to the model, seven variables measuring children’s ability for moving into space loaded on one factor (locomotor skills), while five variables measuring children’s ability for controlling objects loaded on the other factor (object control skills). In addition, the proposed model was found to be invariant across the two groups. Good cross-generalizability of the TGMD appears to support its validity. Physical educators working with young children may use it with confidence when assessing and planning physical education programs involving locomotor and object control skills.
Papers of note in
Science
355
(6325)
Authors: VanHook Annalisa M.
Published: February 2017

This week’s articles report that neural activity promotes localized miRNA-mediated translational silencing at synapses and that activation of B cells triggers an unusual form of autophagy in these cells.
Pseudophosphatase as E3 ubiquitin ligase inhibitor
Authors: Gough Nancy R.
Published: February 2017

The pseudophosphatase STYX prevents the substrate recognition subunit FBXW7 from binding the catalytic E3 ubiquitin ligase complex.
Papers of note in
Nature
542
(7640)
Authors: Foley John F.
Published: February 2017

This week’s articles show how intestinal immune cell populations are controlled and how epithelial cells recognize oncogenic neighbors.
Determining the Clinical Utility of an Absolute Procalcitonin Value for Predicting a Positive Culture Result
Authors: Caffarini Erica M. , DeMott Joshua , Patel Gourang , Lat Ishaq
Published: February 2017

Various procalcitonin ranges have been established to guide antimicrobial therapy; however, there are no data that establish whether the initial procalcitonin value can determine the likelihood of a positive culture result. This study aimed to establish if the initial procalcitonin value, on clinical presentation, has a positive predictive value for any positive culture result. This was a retrospective study of 813 medical intensive care unit patients. Data collected included patient demographics, procalcitonin assay results, sources of infection, culture results, and lengths of stay. Patients were excluded if they were immunocompromised. The primary outcome of this study was to determine a procalcitonin value that would predict any positive culture. Secondary outcomes included the sensitivity, specificity, positive predictive value, and negative predictive value for procalcitonin. After exclusions, a total of 519 patient charts were reviewed to determine the impact of the initial procalcitonin value on culture positivity. In our analyses, the receiver operating characteristic values were 0.62 for all cultures, 0.49 for pulmonary infections, 0.43 for urinary tract infections, and 0.78 for bacteremia. A procalcitonin value of 3.61 ng/ml was determined to be the threshold value for a positive blood culture result (prevalence, 4%). For bacteremia, the sensitivity of procalcitonin was 75%, the specificity was 72%, the positive predictive value was 20%, and the negative predictive value was 97%. Procalcitonin was a poor predictor of culture positivity. An initial procalcitonin value of less than 3.61 ng/ml may be useful in predicting whether bacteremia is absent. Procalcitonin should not be used as the only predictor for determining initiation of antibiotic therapy.
In Vivo
Pharmacodynamic Evaluation of Omadacycline (PTK 0796) against Streptococcus pneumoniae in the Murine Pneumonia Model
Authors: Lepak Alexander J. , Zhao Miao , Marchillo Karen , VanHecker Jamie , Andes David R.
Published: February 2017

Omadacycline is a novel aminomethylcycline antibiotic in clinical development for community-acquired bacterial pneumonia (CABP). We used a neutropenic murine pneumonia infection model to characterize the
in vivo
pharmacodynamic activity of omadacycline against
Streptococcus pneumoniae
. Four strains with various phenotypic resistances to other antimicrobials, including tetracyclines, were utilized. Drug concentration measurements were performed in the plasma and epithelial lining fluid (ELF) after administration of 0.5, 2, 8, and 32 mg/kg. Pharmacokinetic parameters were calculated using a noncompartmental model and were linear over the dose range. Penetration into ELF ranged from 72 to 102%. Omadacycline demonstrated net cidal activity in relation to the initial burden against all four strains. The pharmacokinetic/pharmacodynamic index AUC/MIC correlated well with efficacy (
R
2
= 0.74). The plasma 24-h static dose AUC/MIC values were 16 to 20 (24-h ELF AUC/MIC of 14 to 18). A 1-log
10
kill was achieved at 24-h plasma AUC/MIC values of 6.1 to 180 (24-h ELF AUC/MIC values 6.0 to 200). A 2-log
10
kill was achieved at 24-h plasma AUC/MIC values of 19 to 56 (24-h ELF AUC/MIC of 17 to 47). The targets identified in this study in combination with
in vitro
potency and favorable human pharmacokinetics make omadacycline an attractive candidate for further development and study in patients with CABP.
qnrE1
, a Member of a New Family of Plasmid-Located Quinolone Resistance Genes, Originated from the Chromosome of Enterobacter Species
Authors: Albornoz Ezequiel , Tijet Nathalie , De Belder Denise , Gomez Sonia , Martino Florencia , Corso Alejandra , Melano Roberto G. , Petroni Alejandro
Published: February 2017

qnrE1
, found in a clinical
Klebsiella pneumoniae
isolate, was undetectable by PCR assays used for the six
qnr
families.
qnrE1
was located on a conjugative plasmid (ca. 185 kb) and differed from
qnrB
alleles by 25%. Phylogenetic reconstructions of
qnr
genes and proteins and analysis of the
qnrE1
surroundings showed that this gene belongs to a new
qnr
family and was likely mobilized by IS
Ecp1
from the chromosome of
Enterobacter
spp. to plasmids of
K. pneumoniae
.
Purified Streptococcus pneumoniae Endopeptidase O (PepO) Enhances Particle Uptake by Macrophages in a Toll-Like Receptor 2- and miR-155-Dependent Manner
Authors: Yao Hua , Zhang Hong , Lan Kai , Wang Hong , Su Yufeng , Li Dagen , Song Zhixin , Cui Fang , Yin Yibing , Zhang Xuemei
Published: February 2017

Insights into the host-microbial virulence factor interaction, especially the immune signaling mechanisms, could provide novel prevention and treatment options for pneumococcal diseases.
Streptococcus pneumoniae
endopeptidase O (PepO) is a newly discovered and ubiquitously expressed pneumococcal virulence protein. A PepO-mutant strain showed impaired adherence to and invasion of host cells compared with the isogenic wild-type strain. It is still unknown whether PepO is involved in the host defense response to pneumococcal infection. Here, we demonstrated that PepO could enhance phagocytosis of
Streptococcus pneumoniae
and
Staphylococcus aureus
by peritoneal exudate macrophages (PEMs). Further studies showed that PepO stimulation upregulated the expression of microRNA-155 (miR-155) in PEMs in a time- and dose-dependent manner. PepO-induced enhanced phagocytosis was decreased in cells transfected with an inhibitor of miR-155, while it was increased in cells transfected with a mimic of miR-155. We also revealed that PepO-induced upregulation of miR-155 in PEMs was mediated by Toll-like receptor 2 (TLR2)–NF-κB signaling and that the increased expression of miR-155 downregulated expression of SHIP1. Taken together, these results indicate that PepO induces upregulation of miR-155 in PEMs, contributing to enhanced phagocytosis and host defense response to pneumococci and
Staphylococcus aureus
.
Effector Overlap between the
lac
and
mel
Operons of Escherichia coli: Induction of the
mel
Operon with β-Galactosides
Authors: Narang Atul , Oehler Stefan
Published: February 2017

The
lac
(lactose) operon (which processes β-galactosides) and the
mel
(melibiose) operon (which processes α-galactosides) of
Escherichia coli
have a close historical connection. A number of shared substrates and effectors of the permeases and regulatory proteins have been reported over the years. Until now, β-thiogalactosides like TMG (methyl-β-
d
-thiogalactopyranoside) and IPTG (isopropyl-β-
d
-thiogalactopyranoside) have not generally been considered to be inducers of the
mel
operon. The same is true for β-galactosides such as lactose [β-
d
-galactopyranosyl-(1→4)-
d
-glucose], which is a substrate but is not itself an inducer of the
lac
operon. This report shows that all three sugars can induce the
mel
operon significantly when they are accumulated in the cell by Lac permease. Strong induction by β-thiogalactosides is observed in the presence of Lac permease, and strong induction by lactose (more than 200-fold) is observed in the absence of β-galactosidase. This finding calls for reevaluation of TMG uptake experiments as assays for Lac permease that were performed with
mel

+

strains.

IMPORTANCE
The typical textbook picture of bacterial operons is that of stand-alone units of genetic information that perform, in a regulated manner, well-defined cellular functions. Less attention is given to the extensive interactions that can be found between operons. Well-described examples of such interactions are the effector molecules shared by the
lac
and
mel
operons. Here, we show that this set has to be extended to include β-galactosides, which have been, until now, considered not to effect the expression of the
mel
operon. That they can be inducers of the
mel
operon as well as the
lac
operon has not been noted in decades of research because of the
Escherichia coli
genetic background used in previous studies.
Assessment of Insertion Sequence Mobilization as an Adaptive Response to Oxidative Stress in Acinetobacter baumannii Using IS-seq
Authors: Wright Meredith S. , Mountain Stephanie , Beeri Karen , Adams Mark D.
Published: February 2017

Insertion sequence (IS) elements are found throughout bacterial genomes and contribute to genome variation by interrupting genes or altering gene expression. Few of the more than 30 IS elements described in
Acinetobacter baumannii
have been characterized for transposition activity or expression effects. A targeted sequencing method, IS-seq, was developed to efficiently map the locations of new insertion events in
A. baumannii
genomes and was used to identify novel IS sites following growth in the presence of hydrogen peroxide, which causes oxidative stress. Serial subculture in the presence of subinhibitory concentrations of hydrogen peroxide led to rapid selection of cells carrying an IS
Aba1
element upstream of the catalase-peroxidase gene
katG
. Several additional sites for the elements IS
Aba1
, IS
Aba13
, IS
Aba25
, IS
Aba26
, and IS
Aba125
were found at low abundance after serial subculture, indicating that each element is active and contributes to genetic variation that may be subject to selection. Following hydrogen peroxide exposure, rapid changes in gene expression were observed in genes related to iron homeostasis. The IS insertions adjacent to
katG
resulted in more than 20-fold overexpression of the gene and increased hydrogen peroxide tolerance.

IMPORTANCE
Insertion sequences (IS) contribute to genomic and phenotypic variation in many bacterial species, but little is known about how transposition rates vary among elements or how selective pressure influences this process. A new method for identifying new insertion locations that arise under experimental growth conditions in the genome, termed IS-seq, was developed and tested with cells grown in the presence of hydrogen peroxide, which causes oxidative stress. Gene expression changes in response to hydrogen peroxide exposure are similar to those observed in other species and include genes that control free iron concentrations. New IS insertions adjacent to a gene encoding a catalase enzyme confirm that IS elements can rapidly contribute to adaptive variation in the presence of selection.
A new model for turbidity current behavior based on integration of flow monitoring and precision coring in a submarine canyon
Authors: Symons William O. , Sumner Esther J. , Paull Charles K. , Cartigny Matthieu J.B. , Xu J.P. , Maier Katherine L. , Lorenson Thomas D. , Talling Peter J.
Published: February 2017

Submarine turbidity currents create some of the largest sediment accumulations on Earth, yet there are few direct measurements of these flows. Instead, most of our understanding of turbidity currents results from analyzing their deposits in the sedimentary record. However, the lack of direct flow measurements means that there is considerable debate regarding how to interpret flow properties from ancient deposits. This novel study combines detailed flow monitoring with unusually precisely located cores at different heights, and multiple locations, within the Monterey submarine canyon, offshore California, USA. Dating demonstrates that the cores include the time interval that flows were monitored in the canyon, albeit individual layers cannot be tied to specific flows. There is good correlation between grain sizes collected by traps within the flow and grain sizes measured in cores from similar heights on the canyon walls. Synthesis of flow and deposit data suggests that turbidity currents sourced from the upper reaches of Monterey Canyon comprise three flow phases. Initially, a thin (38–50 m) powerful flow in the upper canyon can transport, tilt, and break the most proximal moorings and deposit chaotic sands and gravel on the canyon floor. The initially thin flow front then thickens and deposits interbedded sands and silty muds on the canyon walls as much as 62 m above the canyon floor. Finally, the flow thickens along its length, thus lofting silty mud and depositing it at greater altitudes than the previous deposits and in excess of 70 m altitude.
Hepatopulmonary fusion: a rare and potentially lethal association with right congenital diaphragmatic hernia
Authors: Jain Vishesh , Yadav Devendra Kumar , Kandasamy Devasenathipathy , Gupta Devendra Kumar
Published: February 2017

Hepatopulmonary fusion is an extremely rare accompaniment of right congenital diaphragmatic hernia. It is associated with abnormal systemic arterial supply and venous drainage of the right lung along with congenital heart disease. Children with this condition have a comparatively poor prognosis. We report a case of right congenital diaphragmatic hernia with hepatopulmonary fusion along with review of the literature with stress on diagnosis and management.
PREVALENCE OF ADVERSE DRUG REACTIONS AMONG HIV/AIDS PATIENTS ON HAART IN UNIVERSITY OF MAIDUGURI TEACHING HOSPITAL (UMTH), NIGERIA: A FOUR-YEAR RETROSPECTIVE STUDY
Authors: Bassi Peter , Gashau Wadzani , Olaf Klungel , Dodoo Alexander , Okonkwo Prosper , Kanki Phyllis
Published: February 2017

Background

Current evidence on highly active antiretroviral therapy (HAART) indicates that each person will have to take the drugs for life [1]. Since 2000, the prevalence of HIV in Nigeria has shown a gradual consistent decline from 5.0% in 2003 to 4.1% in 2010 following the introduction of HAART. While HAART improves the quality of life among HIV patients, adverse drug reactions (ADRs) may compromise quality of life in some patients.

Methods

We performed a retrospective study at HIV/AIDs clinic, UMTH Nigeria, among ART-naive adult patients recruited from January 2006 to December 2010 and followed up for 48 months from commencement of HAART. Database and clinical charts of eligible patients were extracted for clinical information, type of reported ADRs, and physician's decision on whether or not ADRs was serious according to ICH E2A guidelines. Data was analysed using SPSS Ver. 21. Logistic regression was used to calculate odds ratios and of ADR associated with patient and treatment characteristics.

Results

Patients initiated on HAART (n=7260) were reviewed with a prevalence of serious ADRs (53.4%). Commonest ADRs were peripheral neuropathy (11.0%), itching (9.5%), anaemia (9.2%), dyspepsia (9.1%) skin rashes (9.1%), and various forms of dermatitis (5.5%). Almost all (96%) the reported ADRs occurred between 3–18 months of treatment. Patients initiating on a zidovudine and efavirenz-based regimen (p=0.015 and p=0.020 respectively), baseline CD4≤200/ mm3 (P=0.000), unemployed patients (P=0.000), students (p=0.000) and petty traders (p=0.000) were statistically significantly associated with increase occurrence of an ADR.

Conclusions

The study has identified the prevalence, types and the determinants of ADRs among HIV/AIDs patients at UMTH, Nigeria. These findings might be helpful in developing clinical guidelines on ADRs profile as a major criterion for choosing HAART drugs, hence promoting pharmacovigilance of ARVs in Nigeria.
STRENGTHENING PRISON HEALTH SYSTEMS: FEASIBILITY AND CHALLENGES OF INTRODUCING PRISON HEALTH COMMITTEES (PRHCS) IN ZAMBIAN CORRECTIONAL FACILITIES
Authors: Moonga Clement , Chileshe Chisele , Magwende George , Henostroza German , Topp Stephanie
Published: February 2017

Background

In Zambia, prison health and health services are in a state of ‘chronic emergency’. Since 2013, the Zambian Corrections Service (ZCS) partnered with Centre for Infectious Disease Research in Zambia (CIDRZ) to understand and strengthen prisoner health and access to healthcare. A key component of this work was the establishment of 11 facility-level Prison Healthcare Committees (PrHCs) comprising officer and inmate members, with a specific remit to deliver health education and provide monitoring for facility level service access. Findings presented are from operations research evaluating the feasibility of these PrHCs.

Methods

Mixed qualitative methods included, in-depth interviews (11 Ministry and ZCS officials; 6 facility managers) and focus group discussions (FGDs) with members of 6 PrHCs, and 6 groups of non-PrHC-inmates in the same facilities. Memos were generated from participant observation in workshops and meetings preceding and after implementation. All activities were subject to verbal informed consent and interviews and FGDs were audio-recorded with permission.

Results

Key informants were strongly supportive of PrHCs, noting potential for improved health information dissemination, strengthened preventive service-coverage, routine service monitoring and facility-level accountability. PrHC members confirmed ZCS-led training had taken place and that they had been given authority to deliver information-based health interventions and facilitate quicker referrals to primary care. The early phase of implementation (3–6 months at data collection) produced mixed accounts regarding PrHCs' capacity to fulfil other preventive services or conduct data collection. Departure of PrHC members due to transfer and/or release was the most frequently listed challenge.

Conclusions

These data suggest the feasibility of establishing a committee comprising both officers and inmates to address a fundamental gap in facility-level mechanisms for health information delivery and service accountability. Findings nonetheless suggest PrHCs will require iterative adjustments and ongoing problem-solving by local officials. Context-sensitive application of these principles to other settings may yield positive outcomes.
Are parents’ motivations to exercise and intention to engage in regular family-based activity associated with both adult and child physical activity?
Authors: Solomon-Moore Emma , Sebire Simon J , Thompson Janice L , Zahra Jesmond , Lawlor Debbie A , Jago Russ
Published: February 2017

Background/aim

To examine the associations between parents’ motivation to exercise and intention to engage in family-based activity with their own and their child’s physical activity.

Methods

Cross-sectional data from 1067 parent–child pairs (76.1% mother–child); children were aged 5–6 years. Parents reported their exercise motivation (ie, intrinsic motivation, identified regulation, introjected regulation, external regulation and amotivation) as described in self-determination theory and their intention to engage in family-based activity. Parents’ and children’s mean minutes of moderate-to-vigorous-intensity physical activity (MVPA) and mean counts per minute were derived from ActiGraph accelerometers worn for 3 to 5 days (including a mixture of weekdays and weekend days). Multivariable linear regression models, adjusted for parent sex, number of children, indices of multiple deprivation and clustering of children in schools were used to examine associations (total of 24 associations tested).

Results

In fully adjusted models, each unit increase in identified regulation was associated with a 6.08 (95% CI 3.27 to 8.89, p<0.001) min-per-day increase in parents’ MVPA. Parents’ external regulation was associated with children performing 2.93 (95% CI −5.83 to −0.03, p=0.05) fewer minutes of MVPA per day and a 29.3 (95% CI −53.8 to −4.7, p=0.02) accelerometer count-per-minute reduction. There was no evidence of association for the other 21 associations tested.

Conclusions

Future family-based physical activity interventions may benefit from helping parents identify personal value in exercise while avoiding the use of external control or coercion to motivate behaviour.
Preliminary evaluation of the efficacy of an intervention incorporating precision teaching to train procedural skills among final cycle medical students
Authors: Lydon Sinéad , Burns Nadine , Healy Olive , O'Connor Paul , Reid McDermott Bronwyn , Byrne Dara
Published: February 2017

Introduction

A lack of preparedness for practice has been observed among new medical graduates. Simulation technology may offer one means of producing competency. This paper describes the application of a simulation-based intervention incorporating precision teaching (PT), a method of defining target skills, assessing individual progress and guiding instructional decisions, which is used to monitor learning and the development of behavioural fluency in other domains, to procedural skills training. Behavioural fluency refers to accurate and rapid responding that does not deteriorate with time, is resistant to distraction and can be adapted into new, more complex responses.

Method

This study used a between-groups design to evaluate the efficacy of a simulation-based intervention incorporating PT for teaching venepuncture among 11 medical students. The intervention consisted of timed learning trials during which participants carried out the skill in pairs and received corrective feedback. Two control groups of 11 untrained medical students and 11 junior doctors were also included in the study.

Results

Intervention group participants required an average of five trials and 21.9 min to reach the criterion for fluency. The intervention group demonstrated significantly higher accuracy in venepuncture performance than either control group. Improvements persisted over time, did not deteriorate during distraction, generalised to performance with patients and performance of an untargeted skill also improved.

Conclusions

The outcomes of this preliminary study support the application of PT within medical education. The implications of these data for clinical and procedural skills training are explored and suggestions are made for further research.
Contributors to pedestrian distraction and risky behaviours during road crossings in Romania
Authors: Hamann Cara , Dulf Diana , Baragan-Andrada Erika , Price Morgan , Peek-Asa Corinne
Published: February 2017

Objective

Pedestrian fatalities due to collisions with motor vehicles are a large public health problem in Romania, ranking them among the highest in Eastern Europe. The purpose of this study was to gain a better understanding of crash factors by examining how roadway and environmental characteristics contribute to pedestrian distraction and risky behaviours at pedestrian MVC (PMVC) locations in Cluj County, Romania.

Methods

A sample of PMVC locations was selected from the 2010 Cluj County police reported crash database for on-site examination. A total of 100 sites were visited to collect details on site characteristics and typical pedestrian and driver behaviours. Variable distributions were examined and rate ratios of pedestrian distraction and risky behaviours were calculated.

Results

Pedestrian distraction and risky behaviours were observed at rates of 6.3 and 24.3 per 100 observed pedestrians. The majority of distractions were related to electronic device use. Risky behaviours were evenly split between unpredictable, partial use of a crosswalk and midblock illegal crossings. Distractions and risky behaviours decreased as the number of pedestrians and average vehicle speeds at a site increased. RR of distraction was higher at intersections and locations with crosswalks.

Conclusions

Pedestrian distraction was highly correlated with pedestrian risky behaviours at PMVC locations in Romania. Higher pedestrian volume was protective against pedestrian distraction and risky behaviours. Locations with painted crosswalks had increased distraction. Targeted distraction prevention, particularly at intersections and crosswalk locations, may contribute to the prevention of PMVCs.