bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of PomA Mutants Defective in the Functional Assembly of the Na
+
-Driven Flagellar Motor in Vibrio alginolyticus
Authors: Takekawa Norihiro , Li Na , Kojima Seiji , Homma Michio
Published: February 2012

The polar flagellar motor of
Vibrio alginolyticus
rotates using Na
+
influx through the stator, which is composed of 2 subunits, PomA and PomB. About a dozen stators dynamically assemble around the rotor, depending on the Na
+
concentration in the surrounding environment. The motor torque is generated by the interaction between the cytoplasmic domain of PomA and the C-terminal region of FliG, a component of the rotor. We had shown previously that mutations of FliG affected the stator assembly around the rotor, which suggested that the PomA-FliG interaction is required for the assembly. In this study, we examined the effects of various mutations mainly in the cytoplasmic domain of PomA on that assembly. All mutant stators examined, which resulted in the loss of motor function, assembled at a lower level than did the wild-type PomA. A His tag pulldown assay showed that some mutations in PomA reduced the PomA-PomB interaction, but other mutations did not. Next, we examined the ion conductivity of the mutants using a mutant stator that lacks the plug domain, PomA/PomB
ΔL
(Δ41–120), which impairs cell growth by overproduction, presumably because a large amount of Na
+
is conducted into the cells. Some PomA mutations suppressed this growth inhibition, suggesting that such mutations reduce Na
+
conductivity, so that the stators could not assemble around the rotor. Only the mutation H136Y did not impair the stator formation and ion conductivity through the stator. We speculate that this particular mutation may affect the PomA-FliG interaction and prevent activation of the stator assembly around the rotor.
Can lightweight rescuers adequately perform CPR according to 2010 resuscitation guideline requirements?
Authors: Krikscionaitiene Asta , Stasaitis Kestutis , Dambrauskiene Milda , Dambrauskas Zilvinas , Vaitkaitiene Egle , Dobozinskas Paulius , Vaitkaitis Dinas
Published: February 2012

Aim

To evaluate associations between rescuers' anthropometric characteristics and chest compressions (CC) depth according to 2010 resuscitation guidelines.

Methods

186 medical and pharmacy students, never trained in basic life support (BLS) before, underwent video self-instruction training. The participants were asked to perform a BLS test on a manikin connected to a PC for 6 min immediately after training, and the quality of the cardiopulmonary resuscitation (CPR) skills was evaluated.

Results

Women with body weights less than 56 kg were 6.29 times more likely to produce insufficient CCs than women weighing 56–62.7 kg, and 4.72 times more likely to produce insufficient CCs compared with women weighing more than 62.7 kg.

Conclusions

Lightweight rescuers may have difficulty achieving the full compression depth of 5–6 cm required by new resuscitation guidelines. These rescuers require special attention during CPR training, with an emphasis on correct body positioning and use of body weight for CCs.
Stroke intervention for middle cerebral artery thrombus in a young patient with an ipsilateral Spetzler–Martin grade V arteriovenous malformation
Authors: Abla Adib A , Dumont Travis M , Kan Peter , Hopkins L Nelson , Siddiqui Adnan H , Levy Elad I
Published: February 2012

A patient (in their late 20s) was admitted with a right frontal stroke, left hemiparesis and hemianopsia, and a National Institutes of Health Stroke Scale (NIHSS) score of 11. CT perfusion imaging revealed an ischemic penumbra. A CT angiogram showed a Spetzler–Martin grade V arteriovenous malformation (AVM) in the right frontal lobe and a second, smaller AVM in the medial occipital region. Successful mechanical thrombectomy for middle cerebral artery thrombi improved flow from a Thrombolysis in Cerebral Infarction score of 0 to 2b. Following endovascular mechanical thrombectomy, the NIHSS dramatically improved from 11 to 2 and the patient was discharged home in 7 days. Evaluation 1 month after treatment disclosed a nearly complete recovery, with mild residual arm weakness (NIHSS 1). This case illustrates acute stroke intervention in the setting of an ipsilateral, large, high flow AVM in a young adult and is the first such reported case to our knowledge.
IN MEMORIAM CHANDRA KINTALA
Authors: KAPPES MARTIN , MALCHER ANDREAS , WOTSCHKE DETLEF
Published: February 2012

With this contribution we would like to commemorate Chandra M. R. Kintala, who passed away in November 2009. We will give short overviews of his CV and his contributions to the field of theoretical and applied computer science and, given the opportunity, will attempt to present his influence on areas like limited nondeterminism and resources as well as software reliability in an exemplary fashion. Finally, we will briefly touch on some research topics which hopefully will be addressed in the not-so-distant future.
PRODUCT OF PARIKH MATRICES AND COMMUTATIVITY
Authors: MAHALINGAM KALPANA , SUBRAMANIAN K. G.
Published: February 2012

The Parikh vector of a word enumerates the symbols of the alphabet that occur in the word. The Parikh matrix of a word which has been recently introduced, is an extension of the notion of Parikh vector and gives more numerical information about the word in terms of certain subwords. Intensive investigation on various theoretical properties of Parikh matrices has taken place. This paper deals with the problem of finding properties of words so that their Parikh matrices commute.
COLE–COLE DIAGRAM IN A PARAELECTRIC PHASE IN A SMALL PARTICLE: MULTIRESONANCE SINGLE RELAXATION TIME CASE
Authors: HUDAK MATEJ , HUDAK ONDREJ
Published: February 2012

We study the Cole–Cole diagram for the case of a paraelectric particle for which the relaxation time is the same for every mode and the resonance frequency changes and there is an infinite number of such modes. We will calculate the Cole–Cole diagram for temperature a = 10 and damping g = 1 in a and g units (see below) from exact expression for the dynamic susceptibility. We have found that there is a smooth Cole–Cole diagram the curve of which starts from small frequencies 0.001 from the point near Y = 1.5 and X = 0 on the diagram down to the peak (in imaginary part) values of X near 1.6 and Y near 0.5 increasing frequency. Increasing further frequency to 20, the real and imaginary parts tend to zero value. Thus there exists a single maximum of the imaginary part of the susceptibility (for 1000 modes and for 5000 modes), and a single maximum and minimum for the real part of the susceptibility.
ENTROPY AND ITS QUANTUM THERMODYNAMICAL IMPLICATION FOR ANOMALOUS SPECTRAL SYSTEMS
Authors: WANG CHUN-YANG , ZHAO AN-QI , KONG XIANG-MU
Published: February 2012

The state function entropy and its quantum thermodynamical implication for two typical dissipative systems with anomalous spectral densities are studied by investigating on their low-temperature quantum behavior. In all cases, it is found that the entropy decays quickly and vanishes as the temperature approaches zero. This reveals a good conformity with the third law of thermodynamics and provides another evidence for the validity of fundamental thermodynamical laws in the quantum dissipative region.
Airway smooth muscle electrophysiology in a state of flux?
Authors: Janssen Luke J.
Published: February 2012

Activation of chloride currents and release of internally sequestered Ca2+in airway smooth muscle have long been associated with excitation and contraction. Surprisingly, however, two recent publications (Deshpande DA, Wang WC, McIlmoyle EL, Robinett KS, Schillinger RM, An SS, Sham JS, Liggett SB. Nat Med 16: 1299–1304, 2010; Gallos G, Yim P, Chang S, Zhang Y, Xu D, Cook JM, Gerthoffer WT, Emala CW Sr. Am J Physiol Lung Cell Mol Physiol 302: L248–L256, 2012) have linked both events to relaxation. This begs a closer look at our understanding of airway smooth muscle electrophysiology and its contribution to excitation-contraction coupling. This Editorial Focus highlights those two aforementioned studies and several other equally paradoxical findings and proposes some possible reinterpretations of the data and/or new directions of research in which the answers might be found.
TRPV1 induction in airway vagal low-threshold mechanosensory neurons by allergen challenge and neurotrophic factors
Authors: Lieu Tina Marie , Myers Allen C. , Meeker Sonya , Undem Bradley J.
Published: February 2012

We addressed the hypothesis that allergic inflammation in guinea pig airways leads to a phenotypic switch in vagal tracheal cough-causing, low-threshold mechanosensitive Aδ neurons, such that they begin expressing functional transient receptor potential vanilloid (TRPV1) channels. Guinea pigs were actively sensitized to ovalbumin (OVA) and beginning 21 days later exposed via aerosol to OVA daily for 3 days. Tracheal-specific neurons were identified in the nodose ganglion using retrograde tracing techniques. Tracheal specific neurons were isolated, and mRNA expression was evaluated at the single-neuron level using RT-PCR analysis. Electrophysiological studies have revealed that the vast majority of vagal nodose afferent nerves innervating the trachea are capsaicin-insensitive Aδ-fibers. Consistent with this, we found <20% of these neurons express TRPV1 mRNA or respond to capsaicin in a calcium assay. Allergen exposure induced de novo TRPV1 mRNA in a majority of the tracheal-specific nodose neurons ( P < 0.05). The allergen-induced TRPV1 induction was mimicked by applying either brain-derived neurotrophic factor (BDNF) or glial-derived neurotrophic factor (GDNF) to the tracheal lumen. The BDNF-induced phenotypic change observed at the level of mRNA expression was mimicked using a calcium assay to assess functional TRPV1 ion channels. Finally, OVA exposure induced BDNF and GDNF production in the tracheal epithelium, the immediate vicinity of the nodose Aδ -fibers terminations. The induction of TRPV1 in nodose tracheal Aδ -fibers would substantively expand the nature of stimuli capable of activating these cough-causing nerves.
Na,K-ATPase is a target of cigarette smoke and reduced expression predicts poor patient outcome of smokers with lung cancer
Authors: Huynh Thu P. , Mah Vei , Sampson Valerie B. , Chia David , Fishbein Michael C. , Horvath Steve , Alavi Mohammad , Wu Debbie C. , Harper Jeffrey , Sarafian Ted , Dubinett Steven M. , Langhans Sigrid A. , Goodglick Lee , Rajasekaran Ayyappan K.
Published: February 2012

Diminished Na,K-ATPase expression has been reported in several carcinomas and has been linked to tumor progression. However, few studies have determined whether Na,K-ATPase function and expression are altered in lung malignancies. Because cigarette smoke (CS) is a major factor underlying lung carcinogenesis and progression, we investigated whether CS affects Na,K-ATPase activity and expression in lung cell lines. Cells exposed to CS in vitro showed a reduction of Na,K-ATPase activity. We detected the presence of reactive oxygen species (ROS) in cells exposed to CS before Na,K-ATPase inhibition, and neutralization of ROS restored Na,K-ATPase activity. We further determined whether Na,K-ATPase expression correlated with increasing grades of lung adenocarcinoma and survival of patients with smoking history. Immunohistochemical analysis of lung adenocarcinoma tissues revealed reduced Na,K-ATPase expression with increasing tumor grade. Using tissue microarray containing lung adenocarcinomas of patients with known smoking status, we found that high expression of Na,K-ATPase correlated with better survival. For the first time, these data demonstrate that CS is associated with loss of Na,K-ATPase function and expression in lung carcinogenesis, which might contribute to disease progression.
Alternative Exercise Technologies to Fight against Sarcopenia at Old Age: A Series of Studies and Review
Authors: Kemmler Wolfgang , von Stengel Simon
Published: February 2012

The most effective physiologic mean to prevent sarcopenia and related muscle malfunction is a physically active lifestyle, or even better, physical exercise. However, due to time constraints, lack of motivation, or physical limitations, a large number of elderly subjects are either unwilling or unable to perform conventional workouts. In this context, two new exercise technologies, whole-body vibration (WBV) and whole-body electromyostimulation (WB-EMS), may exhibit a save, autonomous, and efficient alternative to increase or maintain muscle mass and function. Regarding WB-EMS, the few recent studies indeed demonstrated highly relevant effects of this technology on muscle mass, strength, and power parameters at least in the elderly, with equal or even higher effects compared with conventional resistance exercise. On the contrary, although the majority of studies with elderly subjects confirmed the positive effect of WBV on strength and power parameters, a corresponding relevant effect on muscle mass was not reported. However, well-designed studies with adequate statistical power should focus more intensely on this issue.
Some Slater′s Type Inequalities for Convex Functions Defined on Linear Spaces and Applications
Authors: Dragomir S. S.
Published: February 2012

Some inequalities of the Slater type for convex functions defined on general linear spaces are given. Applications for norm inequalities and f‐divergence measures are also provided.
Geodesic Effect Near an Elliptical Orbit
Authors: Vîlcu Alina-Daniela
Published: February 2012

Using a differential geometric treatment, we analytically derived the expression for De Sitter (geodesic) precession in the elliptical motion of the Earth through the gravitational field of the Sun with Schwarzschild′s metric. The expression obtained in this paper in a simple way, using a classical approach, agrees with that given in B. M. Barker and R. F. O′Connell (1970, 1975) in a different setting, using the tools of Newtonian mechanics and the Euler‐Lagrange equations.
A Regularized Gradient Projection Method for the Minimization Problem
Authors: Yao Yonghong , Kang Shin Min , Jigang Wu , Yang Pei-Xia
Published: February 2012

We investigate the following regularized gradient projection
algorithm xn+1 = Pc(I − γn(∇f + αnI))xn, n ≥ 0. Under some different control conditions, we prove that this gradient projection algorithm
strongly converges to the minimum norm solution of the minimization problem minx∈Cf(x).
Variational Approach to Quasi‐Periodic Solution of Nonautonomous Second‐Order Hamiltonian Systems
Authors: Kuang Juhong
Published: February 2012

We deal with the quasi‐periodic solutions of the following
second‐order Hamiltonian systems
(t) = ∇F(t, x(t)), where x(t) = (x1(t), …, xN(t)), and we present a new approach via variational methods and Minmax method to obtain the existence of quasi‐periodic solutions to the above equation.
A Newton Interpolation Approach to Generalized Stirling Numbers
Authors: Xu Aimin
Published: February 2012

We employ the generalized factorials to define a Stirling‐type pair {s(n, k; α, β, r), S(n, k; α, β, r)} which unifies various Stirling‐type numbers investigated by previous authors. We make use of the Newton interpolation and divided
differences to obtain some basic properties of the generalized Stirling numbers including the recurrence relation, explicit expression, and generating function. The generalizations of the well‐known Dobinski′s formula are further investigated.
Trends in Adaptive Array Processing
Authors: Singh Hema , Jha Rakesh Mohan
Published: February 2012

Enormous progress has been made during the past five decades in the area of adaptive array processing. Increased computational power has resulted in many practical applications of optimum algorithms. The present paper deals with many facets of array signal processing and adaptive beam forming. It provides a comprehensive description of various beam-forming schemes, adaptive algorithms to adjust the required weighting on antenna elements, direction-of-arrival estimation methods, including their performance comparison. The effects of various types of errors on the performance of an array system are illustrated along with their remedial measures. Since array signal processing has widespread applications, the study is carried out across various disciplines.
Approximation of Common Fixed Points of Nonexpansive Semigroups in Hilbert Spaces
Authors: Zhang Dan , Qin Xiaolong , Gu Feng
Published: February 2012

Let H be a real Hilbert space. Consider on H a nonexpansive semigroup S = {T(s) : 0 ≤ s < ∞} with a common fixed point, a contraction f with the coefficient 0 < α < 1, and a strongly positive linear bounded self‐adjoint operator A with the coefficient >  0. Let /α. It is proved that the sequence {xn} generated by the iterative method converges strongly to a common fixed point x* ∈ F(S), where F(S) denotes the common fixed point of the nonexpansive semigroup. The point x* solves the variational inequality 〈(γf − A)x*, x − x*〉≤0 for all x ∈ F(S).
Study of a Triazole Derivative as Corrosion Inhibitor for Mild Steel in Phosphoric Acid Solution
Authors: Wang Lin , Zhu Ming-Jie , Yang Fa-Chang , Gao Cheng-Wei
Published: February 2012

The corrosion inhibition by a triazole derivative (PAMT) on mild steel in phosphoric acid (H3PO4) solution has been investigated by weight loss and polarization methods. The experimental results reveal that the compound has a significant inhibiting effect on the corrosion of steel in H3PO4solution. It also shows good corrosion inhibition at higher concentration of H3PO4. Potentiodynamic polarization studies have shown that the compound acts as a mixed-type inhibitor retarding the anodic and cathodic corrosion reactions with predominant effect on the cathodic reaction. The values of inhibition efficiency obtained from weight loss and polarization measurements are in good agreement. The adsorption of this compound is found to obey the Langmuir adsorption isotherm. Some kinetic and thermodynamic parameters such as apparent activation energy, frequency factor, and adsorption free energy have been calculated and discussed.
Wireless Sensor Network for Environmental Monitoring: Application in a Coffee Factory
Authors: Valverde J. , Rosello V. , Mujica G. , Portilla J. , Uriarte A. , Riesgo T.
Published: February 2012

Wireless sensor networks have been a big promise during the last few years, but a lack of real applications makes difficult the establishment of this technology. In this paper a real monitoring application in an instant coffee factory is presented. This application belongs to the group of environmental solutions based on wireless sensor networks, and it is focused on the impact of the instant coffee production processes in one of the largest instant coffee factories in Europe. The paper includes the entire application scenario, from the hardware of the WSN nodes to the software that will evaluate the impact and will close the loop.
Periodic Points and Fixed Points for the Weaker (ϕ, φ)‐Contractive Mappings in Complete Generalized Metric Spaces
Authors: Chen Chi-Ming , Sun W. Y.
Published: February 2012

We introduce the notion of weaker (ϕ, φ)‐contractive mapping in complete metric spaces and prove the periodic points and fixed points for this type of contraction. Our results generalize or improve many recent fixed point theorems in the literature.
Association ofFTOPolymorphisms with Early Age of Obesity in Obese Italian Subjects
Authors: Sentinelli Federica , Incani Michela , Coccia Federica , Capoccia Danila , Cambuli Valentina Maria , Romeo Stefano , Cossu Efisio , Cavallo Maria Gisella , Leonetti Frida , Baroni Marco Giorgio
Published: February 2012

Obesity is recognized as a major health problem worldwide. Genetic factors play a major role in obesity, and genomewide association studies have provided evidence that several common variants within the fat mass- and obesity-associated (FTO) gene are significantly associated with obesity. Very limited data is available onFTOin the Italian population. Aims of our study are to investigate: (1) the association ofFTOgene SNPs rs9939609 and rs9930506 with body mass index (BMI) and obesity-related parameters in a large cohort (n=752) of Italian obese subjects; (2) the association between the twoFTOSNPs and age of onset of obesity. Our results demonstrate a strong association betweenFTOSNPs rs9939609 (P<0.043) and rs9930506 (P<0.029) with BMI in the Italian population.FTOrs9930506 was significantly associated with higher BMI in a G allele dose-dependent manner (BMI+1.4 kg/m2per G allele). We also observed that the association with BMI of the twoFTOvariants varied with age, with the carriers of the risk alleles developing an increase in body weight earlier in life. In conclusion, our study further demonstrates a role of the genetic variability inFTOon BMI in a large Italian population.
Phyllanthus urinariaInduces Apoptosis in Human Osteosarcoma 143B Cells via Activation of Fas/FasL- and Mitochondria-Mediated Pathways
Authors: Wu Hsin-Yi , Lin Tsu-Kung , Kuo Hsiao-Mei , Huang Ya-Ling , Liou Chia-Wei , Wang Pei-Wen , Chuang Jiin-Haur , Huang Sheng-Teng
Published: February 2012

Phyllanthus urinaria (P. urinaria), in this study, was used for the treatment of human osteosarcoma cells, which is one of the tough malignancies with few therapeutic modalities. Herein, we demonstrated thatP. urinariainhibited human osteosarcoma 143B cells growth through an apoptotic extrinsic pathway to activate Fas receptor/ligand expression. Both intracellular and mitochondrial reactive oxygen species were increased to lead to alterations of mitochondrial membrane permeability and Bcl-2 family including upregulation of Bid, tBid, and Bax and downregulation of Bcl-2.P. urinariatriggered an intrinsic pathway and amplified the caspase cascade to induce apoptosis of 143B cells. However, upregulation of both intracellular and mitochondrial reactive oxygen species and the sequential membrane potential change were less pronounced in the mitochondrial respiratory-defective 143Bρ0cells compared with the 143B cells. This study offers the evidence that mitochondria are essential for the anticancer mechanism induced byP. urinariathrough both extrinsic and intrinsic pathways.
The PPAR Gamma Agonist Troglitazone Regulates Erk 1/2 Phosphorylation via a PPARγ-Independent, MEK-Dependent Pathway in Human Prostate Cancer Cells
Authors: Bolden Adrienne , Bernard Lynikka , Jones Danielle , Akinyeke Tunde , Stewart LaMonica V.
Published: February 2012

Thiazolidinediones (TZDs) dramatically reduce the growth of human prostate cancer cellsin vitroandin vivo. To determine whether the antitumor effects of TZDs were due in part to changes in the MEK/Erk signaling pathway, we examined the regulation of Erk phosphorylation by the TZD troglitazone within the PC-3 and C4-2 human prostate cancer cell lines. Western blot analysis revealed troglitazone-induced phosphorylation of Erk in both PC-3 and C4-2 cells. Troglitazone-induced increases in Erk phosphorylation were suppressed by the MEK inhibitor U0126 but not by the PPARγantagonist GW9662. Pretreatment with U0126 did not alter the ability of troglitazone to regulate expression of two proteins that control cell cycle, p21, and c-Myc. Troglitazone was also still effective at reducing PC-3 proliferation in the presence of U0126. Therefore, our data suggest that troglitazone-induced Erk phosphorylation does not significantly contribute to the antiproliferative effect of troglitazone.
Analyzing the Pivotal Trial That Compared Sunitinib and IFN-α in Renal Cell Carcinoma, Using a Method That Assesses Tumor Regression and Growth
Authors: Stein Wilfred D. , Wilkerson Julia , Kim Sindy T. , Huang Xin , Motzer Robert J. , Fojo Antonio Tito , Bates Susan E.
Published: February 2012

Purpose: We applied a method that analyzes tumor response, quantifying the rates of tumor growth (g) and regression (d), using tumor measurements obtained while patients receive therapy. We used data from the phase III trial comparing sunitinib and IFN-α in metastatic renal cell carcinoma (mRCC) patients.

Methods: The analysis used an equation that extracts d and g.

Results: For sunitinib, overall survival (OS) was strongly correlated with log g (Rsq = 0.44, P < 0.0001); much less with log d (Rsq = 0.04; P = 0.0002). The median g of tumors in these patients (0.00082 per days; log g = −3.09) was about half that (P < 0.001) of tumors in patients receiving IFN-α (0.0015 per day; log g = −2.81). With IFN-α, the OS/log g correlation (Rsq = 0.14) was weaker. Values of g from measurements obtained by study investigators or central review were highly correlated (Rsq = 0.80). No advantage resulted in including data from central review in regressions. Furthermore, g can be estimated accurately four months before treatment discontinuation. Extrapolating g in a model that incorporates survival generates the hypothesis that g increased after discontinuation of sunitinib but did not accelerate.

Conclusions: In patients with mRCC, sunitinib reduced tumor growth rate, g, more than did IFN-α. Correlating g with OS confirms earlier analyses suggesting g may be an important clinical trial endpoint, to be explored prospectively and in individual patients. Clin Cancer Res; 18(8); 2374–81. ©2012 AACR.
Alzheimer’s Disease Is Associated with a Low Prevalence of Hypertension
Authors: Kuyumcu Mehmet Emin , Yesil Yusuf , Oztürk Zeynel Abidin , Halil Meltem , Ulger Zekeriya , Yavuz Burcu Balam , Cankurtaran Mustafa , Cınar Esat , Arıoğul Servet
Published: February 2012

Background/Aim: Dementia is one of the most common health problems in the world. Alzheimer’s disease (AD) is the most common form of dementia. The relation between blood pressure (BP) and dementia has been the subject of numerous epidemiological studies, and midlife hypertension (HT) is a risk factor for AD. The association between BP and risk of dementia is lower in the older population. The aim of this study was to examine the association between the prevalence of HT and AD in elderly individuals. Methods: In this cross-sectional study, 193 patients with AD and 1,860 patients with normal cognitive function were evaluated. Results: The prevalence of HT was lower in the AD group (60.6 vs. 70.5%; p = 0.005). In multivariate analysis, AD was found to be negatively correlated with HT (OR = 0.649; 95% CI 0.461–0.916). Conclusion: The prevalence of HT was lower in patients with AD compared to subjects without AD. Physicians who deal with AD patients must keep in mind that the need for antihypertensive medication may decline during the dementia process.
Mutations in the Essential Escherichia coli Gene, yqgF, and Their Effects on Transcription
Authors: Iwamoto Akira , Osawa Atsushi , Kawai Makiko , Honda Hirofumi , Yoshida Saori , Furuya Nobuhisa , Kato Jun-ichi
Published: February 2012

The Escherichia coli yqgF gene is highly conserved across a broad spectrum of bacterial genomes. The gene was first identified as being essential for cell growth during screening for targets for broad-spectrum antibiotics. YqgF is structurally similar to RuvC, a Holliday junction resolvase, but its function has not been established. This study describes the isolation of a temperature-sensitive yqgF mutant, the growth of which was inhibited by rho or nusA multicopy plasmids, indicating that YqgF is involved in transcription. Rho is a global transcription termination factor that acts at Rho-dependent terminator sites, which exist not only at the ends of genes but also within genes. The transcription of genes possessing intragenic, or upstream, Rho-dependent terminators was reduced in temperature-sensitive yqgF mutants. This transcription inhibition was sensitive to the Rho inhibitor, bicyclomycin. In addition, the transcription of mutant tnaA genes defective for upstream Rho-dependent termination was not significantly affected by the yqgF mutation. Taken together, these results suggest that YqgF is involved in anti-termination at Rho-dependent terminators in vivo.
Associations of Pregnancy Complications With Calculated Cardiovascular Disease Risk and Cardiovascular Risk Factors in Middle Age
Authors: Fraser Abigail , Nelson Scott M. , Macdonald-Wallis Corrie , Cherry Lynne , Butler Elaine , Sattar Naveed , Lawlor Debbie A.
Published: February 2012

Background—

The nature and contribution of different pregnancy-related complications to future cardiovascular disease (CVD) and its risk factors and the mechanisms underlying these associations remain unclear.

Methods and Results—

We studied associations of pregnancy diabetes mellitus, hypertensive disorders of pregnancy, preterm delivery, and size for gestational age with calculated 10-year CVD risk (based on the Framingham score) and a wide range of cardiovascular risk factors measured 18 years after pregnancy (mean age at outcome assessment, 48 years) in a prospective cohort of 3416 women. Gestational diabetes mellitus was positively associated with fasting glucose and insulin, even after adjustment for potential confounders, whereas hypertensive disorders of pregnancy were associated with body mass index, waist circumference, blood pressure, lipids, and insulin. Large for gestational age was associated with greater waist circumference and glucose concentrations, whereas small for gestational age and preterm delivery were associated with higher blood pressure. The association with the calculated 10-year CVD risk based on the Framingham prediction score was odds ratio 1.31 (95 confidence interval, 1.11–1.53) for preeclampsia and 1.26 (95 confidence interval, 0.95–1.68) for gestational diabetes mellitus compared with women without preeclampsia and without gestational diabetes mellitus, respectively.

Conclusions—

Hypertensive disorders of pregnancy and pregnancy diabetes mellitus are independently associated with an increased calculated 10-year CVD risk. Preeclampsia may be the better predictor of future CVD because it was associated with a wider range of cardiovascular risk factors. Our results suggest that pregnancy may be an important opportunity for early identification of women at increased risk of CVD later in life.
Validation of the Bleeding Academic Research Consortium Definition of Bleeding in Patients With Coronary Artery Disease Undergoing Percutaneous Coronary Intervention
Authors: Ndrepepa Gjin , Schuster Tibor , Hadamitzky Martin , Byrne Robert A. , Mehilli Julinda , Neumann Franz-Josef , Richardt Gert , Schulz Stefanie , Laugwitz Karl-Ludwig , Massberg Steffen , Schömig Albert , Kastrati Adnan
Published: February 2012

Background—

The Bleeding Academic Research Consortium (BARC) has recently proposed a unified definition of bleeding in patients receiving antithrombotic therapy. We investigated the relationship between bleeding events as defined by BARC and 1-year mortality in patients undergoing percutaneous coronary intervention (PCI) and assessed whether the BARC bleeding definition is superior to existing bleeding definitions in regard to mortality prediction in patients after PCI procedures.

Methods and Results—

This study represents a patient-level pooled analysis of 12 459 patients recruited in 6 randomized trials of patients undergoing PCI. Bleeding events were assessed with the use of BARC, Thrombolysis in Myocardial Infarction (TIMI), and Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) trial criteria. The primary outcome was 1-year mortality. Bleeding occurred in 1233 patients (9.9%) according to BARC (679 patients or 5.4% with BARC class ≥2 bleeding), in 374 patients (3.0%) according to TIMI, and in 491 patients (3.9%) according to REPLACE-2 criteria. There were 340 deaths (2.7%) over the first year after PCI. BARC class ≥2 bleeding was associated with a significant increase in 1-year mortality (adjusted hazard ratio 2.72; 95% confidence interval, 2.03–3.63). The predictivity of a multivariable model for 1-year mortality was significantly improved after inclusion of bleeding defined according to BARC to an extent comparable to that provided by TIMI and REPLACE-2 criteria.

Conclusions—

The present study demonstrated a close association between bleeding events defined according to BARC and 1-year mortality after PCI.
Associations of Maternal Prepregnancy Body Mass Index and Gestational Weight Gain With Adult Offspring Cardiometabolic Risk Factors
Authors: Hochner Hagit , Friedlander Yechiel , Calderon-Margalit Ronit , Meiner Vardiella , Sagy Yael , Avgil-Tsadok Meytal , Burger Ayala , Savitsky Bella , Siscovick David S. , Manor Orly
Published: February 2012

Background—

Accumulating evidence demonstrates that both maternal prepregnancy body mass index (mppBMI) and gestational weight gain (GWG) are associated with adult offspring adiposity. However, whether these maternal attributes are related to other cardiometabolic risk factors in adulthood has not been comprehensively studied.

Methods and Results—

We used a birth cohort of 1400 young adults born in Jerusalem who had extensive archival data and clinical information at 32 years of age to prospectively examine the associations of mppBMI and GWG with adiposity and related cardiometabolic outcomes. Greater mppBMI, independently of GWG and confounders, was significantly associated with higher offspring BMI, waist circumference, systolic and diastolic blood pressures, insulin, and triglycerides and with lower high-density lipoprotein cholesterol. For example, the effect sizes were translated to nearly 5 kg/m
2
higher mean BMI, 8.4 cm higher waist circumference, 0.13 mmol/L (11.4 mg/dL) higher triglycerides, and 0.10 mmol/L (3.8 mg/dL) lower high-density lipoprotein cholesterol among offspring of mothers within the upper mppBMI quartile (mppBMI >26.4 kg/m
2
) compared with the lower quartile (mppBMI <21.0 kg/m
2
). GWG, independently of mppBMI, was positively associated with offspring adiposity; differences of 1.6 kg/m
2
in BMI and 2.4 cm in waist were observed when offspring of mothers in the upper (GWG >14 kg) and lower (GWG <9 kg) quartiles of GWG were compared. Further adjustment for offspring adiposity attenuated the observed associations to the null.

Conclusions—

Maternal size both before and during pregnancy is associated with cardiometabolic risk factors in young adult offspring. The associations appear to be driven mainly by offspring adiposity. Future studies that explore mechanisms underlying the intergenerational cycle of obesity are warranted to identify potentially novel targets for cardiometabolic risk-reduction interventions.
Granting Conscientious Exemptions: The Need to Take Sides
Authors: Nehushtan Yossi
Published: February 2012

Abstract

There are several possible views of the proper way in which the state should respond to claims to be granted conscientious exemptions. This article discusses, and ultimately rejects, two main approaches to the issue of granting conscientious exemptions: the neutral approach and the ‘equal-regard’ approach. According to the neutral approach the decision whether to grant an exemption should not be affected, at least not directly, by the content of a person’s conscience. The equal-regard approach suggests that, when an exemption is granted to a non-religious conscientious objector, an exemption should also be granted to his equivalent religious objector, and vice versa. It is suggested that the state has to take sides and to evaluate the content of one’s conscience in order to decide whether to grant him an exemption from the law. The general argument that intolerance should normally not be tolerated provides one reason, among others, why the content of someone’s conscience is significant when deciding when to grant conscientious exemptions.
Effects of Aerosol Solubility and Regeneration on Mixed-Phase Orographic Clouds and Precipitation
Authors: Xue Lulin , Teller Amit , Rasmussen Roy , Geresdi Istvan , Pan Zaitao , Liu Xiaodong
Published: February 2012

A detailed bin aerosol-microphysics scheme has been implemented into the Weather Research and Forecast Model to investigate the effects of aerosol solubility and regeneration on mixed-phase orographic clouds and precipitation. Two-dimensional simulations of idealized moist flow over two identical bell-shaped mountains were carried out using different combinations of aerosol regeneration, solubility, loading, ice nucleation parameterizations, and humidity. The results showed the following. 1) Pollution and regenerated aerosols suppress the riming process in mixed-phase clouds by narrowing the drop spectrum. In general, the lower the aerosol solubility, the broader the drop spectrum and thus the higher the riming rate. When the solubility of initial aerosol increases with an increasing size of aerosol particles, the modified solubility of regenerated aerosols reduces precipitation. 2) The qualitative effects of aerosol solubility and regeneration on mixed-phase orographic clouds and precipitation are not affected by different ice nucleation parameterizations. 3) The impacts of aerosol properties on rain are similar in both warm- and mixed-phase clouds. Aerosols exert weaker impact on snow and stronger impact on graupel compared to rain as graupel production is strongly affected by riming. 4) Precipitation of both warm- and mixed-phase clouds is most sensitive to aerosol regeneration, then to aerosol solubility, and last to modified solubility of regenerated aerosol; however, the precipitation amount is mainly controlled by humidity and aerosol loading.
Evaluation of Radial Artery Atherosclerosis by Intravascular Ultrasound
Authors: Moon Keon-Woong , Kim Ji-Hoon , Yoo Ki-Dong , Oh Su-Sung , Kim Dong-Bin , Kim Chul-Min
Published: February 2012

We quantified radial artery atherosclerosis by intravascular ultrasound (IVUS) and determined the relationship between established cardiovascular risk factors and the extent of atherosclerotic plaque. Intravascular ultrasound examination of the radial artery was performed in patients undergoing transradial angiography or intervention. Total 50-mm segments starting at the radioulnar bifurcation were analyzed at 2-mm intervals to compute atheroma volume. In 115 consecutive patients, atheroma volume averaged 67.4 mm3 and percentage atheroma volume was 25.2%. Radial arteries showed age-related acceleration of atherosclerosis. Total atheroma volume was strongly associated with square of age and male gender. Hypertension and diabetes were strong independent predictors of larger radial artery atheroma burden. Radial artery atherosclerosis, which can be quantitatively analyzed by IVUS, could be used as a surrogate marker for atherosclerosis.
A Distributed Perspective on Instructional Leadership in International Baccalaureate (IB) Schools
Authors: Lee Moosung , Hallinger Philip , Walker Allan
Published: February 2012

Purpose: The purpose of this study is to provide a better understanding of how instructional leadership responsibilities are distributed in International Baccalaureate (IB) schools in East Asia. Research Design: Case studies were conducted in five international schools located in Thailand, Vietnam, Hong Kong, and China. These schools were selected on the basis of location in East Asia, the offering of the full continuum of the IB’s three programs, and evidence of prior academic success. In total, 68 teachers and administrators and 25 students were interviewed. Qualitative analysis of the interview data was conducted using pattern coding. Findings: Three broad instructional leadership practices were identified: curriculum articulation, cross-program activities, and strategic staffing. These appeared to enhance curriculum consistency and coherence across the three IB programs, a problem that had been identified in full-continuum IB schools. The qualitative data suggested that distributed instructional leadership forged and sustained professional interactions among staff across programs and organizational units. Conclusions: IB schools globally are often structurally separated into two or three organizational units (e.g., primary, middle, high school). These units operate IB programs that, despite their common origin and international philosophy, employ distinct pedagogical and curricular approaches. The findings reinforce the importance of acting intentionally to distribute responsibilities for instructional leadership widely throughout the school. They also support the assertion that international schools offer a unique and fruitful context for studying distributed instructional leadership.
The Rasch Rating Model and the Disordered Threshold Controversy
Authors: Adams Raymond J. , Wu Margaret L. , Wilson Mark
Published: February 2012

The Rasch rating (or partial credit) model is a widely applied item response model that is used to model ordinal observed variables that are assumed to collectively reflect a common latent variable. In the application of the model there is considerable controversy surrounding the assessment of fit. This controversy is most notable when the set of parameters that are associated with the categories of an item have estimates that are not ordered in value in the same order as the categories. Some consider this disordering to be inconsistent with the intended order of the response categories in a variable and often term it reversed deltas. This article examines a variety of derivations of the model to illuminate the controversy. The examination of the derivations shows that the so-called parameter disorder and order of the response categories are separate phenomena. When the data fit the Rasch rating model the response categories are ordered regardless of the (order of the) values of the parameter estimates. In summary, reversed deltas are not necessarily evidence of a problem. In fact the reversed deltas phenomenon is indicative of specific patterns in the relative numbers of respondents in each category. When there are preferences about such relative numbers in categories, the patterns of deltas may be a useful diagnostic.
All‐Cause Mortality after Tracheostomy at a Tertiary Care Hospital over a 10‐Month Period
Authors: Kejner Alexandra E. , Castellanos Paul F. , Rosenthal Eben L. , Hawn Mary T.
Published: February 2012

Objective

To evaluate perioperative mortality after tracheostomy in intensive care unit (ICU) patients undergoing routine tracheostomy over a 10‐month period.

Study Design

Case series with planned data collection.

Setting

Tertiary care hospital.

Subjects

Mechanically ventilated patients.

Methods

Prospective analysis of ICU patients undergoing tracheostomy placement over 10 months was performed. Variables evaluated were demographics, pretracheostomy length of stay, time on ventilator, time to death, preoperative comorbidities, and cause of death.

Results

There were 129 consultations resulting in 115 tracheostomies, of which 100 were included for study. The overall 30‐day postoperative mortality rate was 25%, including palliative care deaths. Cause of death in all cases was due to a preexisting condition and not from tracheostomy. Patients who died within the 30‐day postoperative period were found to have significant differences in age, pretracheostomy length of stay, location of tracheostomy, and preoperative comorbidity scores. No significant difference was found in time on ventilator, sex, or race/ethnicity. Mean time from consultation to tracheostomy was 2.5 days (range, 0‐12 days).

Conclusion

High rates of mortality after tracheostomy can possibly affect hospital quality ratings for surgical services. There were no deaths directly related to surgery. Despite this, the mortality rate in this population was quite high. This illustrates the significant disease burden in these patients and the need to stratify postoperative mortality as well as to consider comorbidity and age when evaluating patients for tracheostomy.
Diagnosis and Management of Humeral Head Bone Loss in Shoulder Instability
Authors: Skendzel Jack G. , Sekiya Jon K.
Published: February 2012

Humeral head bone defects (Hill-Sachs lesions) are caused by anterior shoulder dislocation with impaction of the posterosuperior humeral head onto the anterior glenoid rim. Frequently, these bony lesions are associated with glenohumeral instability, and large lesions may contribute to recurrent instability after failure of a soft tissue repair. To improve outcomes and minimize the risk of persistent instability, a thorough understanding of the biomechanics of humeral bone loss is required. Detection and quantification of clinically relevant humeral head bone loss are performed through an accurate history, physical examination, and interpretation of imaging studies. The diagnosis and treatment options for reverse Hill-Sachs lesions are discussed, and the various treatment options for Hill-Sachs lesions are reviewed, including operative techniques to limit engagement of the deformity by soft tissue transfer, rotational osteotomy, bone grafting, or osteochondral transplantation.
Anterior Glenohumeral Laxity Is Associated With Posterior Shoulder Tightness Among Professional Baseball Pitchers
Authors: Laudner Kevin , Meister Keith , Noel Bria , Deter Tricia
Published: February 2012

Background: Baseball pitchers often have increased anterior glenohumeral (GH) laxity and posterior shoulder tightness due to large forces produced during the throwing motion. As such, many clinicians have hypothesized that a relationship exists between these common characteristics.

Hypothesis: A negative relationship will exist between anterior GH laxity and the summation of GH adduction range of motion (ROM) and GH internal rotation ROM asymmetry.

Study Design: Cross-sectional study; Level of evidence, 3.

Methods: Anterior GH laxity, GH rotation ROM, and GH horizontal adduction ROM were measured in 58 asymptomatic professional baseball pitchers. Differences in GH internal rotation at 90° of abduction were calculated between both shoulders. A multiple regression analysis was used to determine the strength of the relationships between anterior GH laxity (dependent variable) and GH adduction ROM and GH internal rotation ROM asymmetry (independent variables) ( P < .05).

Results: A large portion of anterior GH laxity was predicted by the summation of GH adduction ROM and GH internal rotation ROM asymmetry ( r2 = .45, P = .001). Furthermore, increased anterior GH laxity had a significant relationship with both decreased GH horizontal adduction ROM ( r = .53, P = .001) and differences in GH internal rotation ROM ( r = .43, P = .001).

Conclusion: The results of this study suggest that decreased GH horizontal adduction and internal rotation ROM may be considered partial predictors for increased anterior GH laxity in the throwing arm of baseball players. Because of the association between these variables, clinicians may find it advantageous to address posterior shoulder tightness during the prevention, diagnosis, and treatment of shoulder injuries associated with anterior GH laxity.
Breastfeeding among Women Exposed to Antidepressants during Pregnancy
Authors: Gorman Jessica R. , Kao Kelly , Chambers Christina D.
Published: February 2012

This prospective cohort study compares the breastfeeding outcomes of women exposed to selective serotonin reuptake inhibitor (SSRI) antidepressants at the time of delivery, those who discontinued use prior to delivery, and those not exposed. Participants include 466 pregnant women who enrolled in the California Teratogen Information Service Clinical Research Program (CTIS) over 10 years. In bivariate analyses, breastfeeding rates were significantly different across SSRI exposure groups, with unexposed women having the highest rates. We used logistic regression to examine the relationship between SSRI exposure and breastfeeding outcomes. After adjustment for potential confounders, those exposed to an SSRI both prior to delivery (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.20-0.94) and at the time of delivery (OR, 0.34; 95% CI, 0.16-0.72) were significantly less likely to initiate breastfeeding as compared to unexposed women. Women exposed to an SSRI during pregnancy appear to be at risk for poorer breastfeeding outcomes and may benefit from additional education and support.