bluuebunny/crossref_metadata_2025 huggingface dataset:
Is butyrate the link between diet, intestinal microbiota and obesity‐related metabolic diseases?
Authors: Brahe L. K. , Astrup A. , Larsen L. H.
Published: August 2013

It is increasingly recognized that there is a connection between diet, intestinal microbiota, intestinal barrier function and the low‐grade inflammation that characterizes the progression from obesity to metabolic disturbances, making dietary strategies to modulate the intestinal environment relevant. In this context, the ability of some Gram‐positive anaerobic bacteria to produce the short‐chain fatty acid butyrate is interesting. A lower abundance of butyrate‐producing bacteria has been associated with metabolic risk in humans, and recent studies suggest that butyrate might have an anti‐inflammatory potential that can alleviate obesity‐related metabolic complications, possibly due to its ability to enhance the intestinal barrier function.

Here, we review and discuss the potential of butyrate as an anti‐inflammatory mediator in metabolic diseases, and the potential for dietary interventions increasing the intestinal availability of butyrate.
Human periodontal ligament cell sheets cultured on amniotic membrane substrate
Authors: Adachi K , Amemiya T , Nakamura T , Honjyo K , Kumamoto S , Yamamoto T , Bentley AJ , Fullwood NJ , Kinoshita S , Kanamura N
Published: August 2013

Objective

Periodontal ligament (PDL) cells and their substrates play key roles in periodontal regeneration. However, there has been no report on the use of amniotic membrane (AM) as a substrate for culturing PDL cells. In the current study, we conducted an analysis of PDL cells cultivated on AM to determine the distribution of factors responsible for maintaining the characteristics of PDL.

Materials and Methods

Amniotic membrane was obtained from women undergoing cesarean sections, whereas PDL tissue was obtained from human maxillary third molars. The harvested PDL cells were maintained in explant culture for three or four passages, following which they were cultured on AM.

Results

After 3 weeks of culture, the PDL cells had grown well on AM. Immunofluorescence showed that these cells were capable of proliferating and potentially maintaining their PDL‐like properties. In addition, strong cell–cell adhesion structures, namely desmosomes and tight junctions, were shown to be present between cells. Electron microscopy images showed that the cultured PDL cells had differentiated and proliferated on AM with lateral conjugation and adhesion to AM.

Conclusion

We conclude that AM may represent a suitable substrate for culturing PDL cells and that PDL cells cultured on AM show sheet formation.
Safe Single‐Dose Administration of Propofol in Patients with Established Brugada Syndrome: A Retrospective Database Analysis
Authors: FLAMÉE PANAGIOTIS , DE ASMUNDIS CARLO , BHUTIA JIGME T. , CONTE GIULIO , BECKERS STEFAN , UMBRAIN VINCENT , VERBORGH CHRISTIAN , CHIERCHIA GIAN‐BATTISTA , VAN MALDEREN SOPHIE , CASADO‐ARROYO RUBÉN , SARKOZY ANDREA , BRUGADA PEDRO , POELAERT JAN
Published: August 2013

Background

Propofol is an anesthetic drug with a very attractive pharmacokinetic profile, which makes it the induction agent of choice, especially in day‐case surgery. Data on its potential proarrhythmic effects in patients with Brugada syndrome (BS) patients are still lacking. The aim of our study was to investigate whether a single dose of propofol triggered any adverse events in consecutive high‐risk patients with BS.

Methods

All consecutive patients with BS having undergone an implantable cardiac defibrillator implantation under general anesthesia were eligible for this study. The anesthetic chart of each patient was reviewed, and the occurrence of malignant arrhythmic events as well as the need for defibrillation during induction and maintenance of anesthesia was investigated. Further monitoring of the patient comprised five‐lead electrocardiogram (ECG), pulse oxymetry, and continuous carbon dioxide monitoring through side sampling from the ventilator tubes. Anesthesia was induced with propofol and sufentanyl. Injection of propofol occurred in a single‐shot bolus—as often performed by most anesthetists—over a few seconds. Anesthesia was maintained with volatile anesthetics (sevoflurane or desflurane) in an oxygen‐air mixture.

Results

From 1996 to 2011, 57 high‐risk patients with BS (35 males; mean age: 43 ± 16 years) underwent an automated implantable cardioverter defibrillator implantation at our center using propofol as induction drug of general anesthesia. Three patients had a history of spontaneous type I ECG, three had aborted sudden death, and 51 had a history of recurrent or unexplained syncope. The induction dose ranged between 0.8 mg/kg and 5.0 mg/kg (2.2 ± 0.7 mg/kg). Only one case received propofol to maintain anesthesia. The surgical procedure involved an anesthetic period of 75 ± 25 minutes. No patient developed a malignant rhythm during induction and maintenance of anesthesia. All patients were then safely discharged from the postanesthetic care unit after 1 hour. No adverse events were noticed during the recovery phase. In our study, administration of a single‐dose propofol in patients with BS was safe. Nevertheless, extreme caution is still recommended when conducting general anesthesia in patients with BS, especially if BS patients are sedated with propofol for longer periods.
Washout times of desflurane, sevoflurane and isoflurane from the GE healthcare Aisys® and Avance® Carestation® and Aestiva® Anesthesia System
Authors: Kim Tae W. , Tham Robert Q.
Published: August 2013

Background/Aim

Malignant hyperthermia susceptible patients may experience a fatal reaction to volatile anesthetic gases. This study sought to determine the washout characteristics of desflurane, sevoflurane, and isoflurane from the Aisys®, Avance®, and Aestiva® anesthesia machines. (GE Healthcare, Madison, WI, USA).

Methods

All machines were inspected by a GE Healthcare engineer prior to testing. The machines were primed with desflurane 7 vol%, sevoflurane 2.5 vol%, and isoflurane 1.2 vol% on three separate occasions for 2 h each with each gas. The Aisys® and Avance® were tested with and without an Advanced Breathing System (ABS™, GE Healthcare, Madison, WI, USA). The Aestiva® was tested without modification to its breathing system. Additionally, the Aisys was evaluated with desflurane 1.2 vol% and the Avance with a preflushed fresh gas line was tested with an autoclaved ABS. After priming, disposable components of the patient breathing system were replaced. The fresh gas flow was increased to 15 lpm. Gas measurements were recorded until the concentration was 4 parts per million (p.p.m).

Results

The fastest median washout time was achieved by the Avance in 3 min or less without an ABS or with an autoclaved ABS. The longest median time was 35 min for the Aestiva®. Clearance of desflurane was the most time consuming for all machines.

Conclusion

This study demonstrates that saturated vapor pressure and priming concentration exert a greater effect on washout times than gas solubility. The Aisys utilizes an electronic vaporizer system that may expose the breathing system to retained saturated vapor. The breathing systems for all machines may hinder washout of gases.
The overexpression of a maize mitogen‐activated protein kinase gene (ZmMPK5) confers salt stress tolerance and induces defence responses in tobacco
Authors: Zhang D. , Jiang S. , Pan J. , Kong X. , Zhou Y. , Liu Y. , Li D.
Published: August 2013

As sessile organisms, plants are exposed to potential dangers, including multiple biotic and abiotic stresses. The mitogen‐activated protein kinase (MAPK) is a universal signalling pathways involved in these processes. A previous study showed that maize ZmMPK5 is induced by various stimuli at transcriptional and post‐translational levels. In this study, ZmMPK5 was overexpressed in tobacco to further analyse its biological functions. Under salt and oxidative stresses, ZmMPK5‐overexpressing lines displayed less severe damage and stronger growth phenotypes corresponding to a series of physiological changes. In addition, the transgenic lines accumulated less reactive oxygen species (ROS) and had higher levels of antioxidant enzyme activity and metabolites than wild‐type (WT) plants following NaCl treatment. Quantitative RT‐PCR revealed that the expression of ROS‐related and stress‐responsive genes was higher in transgenic plants than in WT plants. Furthermore, transgenic lines exhibited enhanced resistance to viral pathogens, and expressed constitutively higher transcript levels of pathogenesis‐related genes, such as PR1a, PR4, PR5 and EREBP. Taken together, these results demonstrated that ZmMPK5 is involved in salt stress, oxidative stress and pathogen defence signalling pathways, and its function may be at least partly devoted to efficiently eliminating ROS accumulation under salt stress.
The Temporal Consistency of Personality Effects: Evidence from the British Household Panel Survey
Authors: Bloeser Andrew J. , Canache Damarys , Mitchell Dona‐Gene , Mondak Jeffery J. , Poore Emily Rowan
Published: August 2013

Personality traits have been posited to function as stable influences on political attitudes and behavior. Although personality traits themselves exhibit high levels of temporal stability, it is not yet known whether the effects of these traits are marked by comparable temporal consistency. To address this question, this research note examines data from Wave 13 (2003–2004), Wave 15 (2005–2006) and Wave 17 (2007–2008) of the British Household Panel Survey (BHPS). Twenty‐seven behavioral and 14 attitudinal dependent variables are studied. Consistency of effects is gauged via a series of multilevel models in which personality effects are permitted to vary by year. High levels of temporal consistency are observed for personality traits as represented by the Big Five framework.
Personality Dispositions and Political Preferences Across Hard and Easy Issues
Authors: Johnston Christopher D. , Wronski Julie
Published: August 2013

A wealth of theoretical and empirical work suggests that conservative orientations in the mass public are meaningfully associated with personality dispositions related to needs for certainty and security. Recent empirical research, however, suggests that (1) associations between these needs and economic conservatism are substantially weaker than associations with conservative identifications and social conservatism, and (2) political sophistication plays an important role in moderating the translation of needs into political preferences within the economic domain. The present article extends this work by offering a theoretical model of the heterogeneous translation of personality dispositions into political preferences across issues and issue domains. We argue that these needs structure preferences directly for highly symbolic issues like those in the social domain, but they structure preferences indirectly through partisanship for difficult issues like those in the economic domain. We test this theory utilizing a national survey experiment in the United States and explore its broader implications for both the literature on the psychological determinants of political ideology and for debates over the “culture war” in the United States.
Integrating Models and Data to Estimate the Structural Reliability of Utility Poles During Hurricanes
Authors: Han Seung‐Ryong , Rosowsky David , Guikema Seth
Published: August 2013

Utility systems such as power and communication systems regularly experience significant damage and loss of service during hurricanes. A primary damage mode for these systems is failure of wooden utility poles that support conductors and communication lines. In this article, we present an approach for combining structural reliability models for utility poles with observed data on pole performance during past hurricanes. This approach, based on Bayesian updating, starts from an imperfect but informative prior and updates this prior with observed performance data. We consider flexural and foundation failure mechanisms in the prior, acknowledging that these are an incomplete, but still informative, subset of the possible failure mechanisms for utility poles during hurricanes. We show how a model‐based prior can be updated with observed failure data, using pole failure data from Hurricane Katrina as a case study. The results of this integration of model‐based estimates and observed performance data then offer a more informative starting point for power system performance estimation for hurricane conditions.
On the Evaluation of the Elastic Modulus of Soft Materials Using Beams with Unknown Initial Curvature
Authors: Khatam H. , Ravi‐Chandar K.
Published: August 2013

A non‐linear optimization procedure is established to determine the elastic modulus of slender, soft materials using beams with unknown initial curvature in the presence of large rotations. Specifically, the deflection of clamped‐free beams under self‐weight – measured at different orientations with respect to gravity – is used to determine the modulus of elasticity and the intrinsic curvature in the unloaded state. The approach is validated with experiments on a number of different materials – steel, polyetherimide, rubber and pig skin. Because the loading is limited to self‐weight, the strain levels attained in these tests are small enough to assume a linear elastic material behaviour. This non‐destructive methodology is also applicable to engineered tissues and extremely delicate materials in order to obtain a quick estimate of the material's elastic modulus.
Stiffness Improvement of 45S5 Bioglass®‐Based Scaffolds Through Natural and Synthetic Biopolymer Coatings: An Ultrasonic Study
Authors: Hum J. , Luczynski K. W. , Nooeaid P. , Newby P. , Lahayne O. , Hellmich C. , Boccaccini A. R.
Published: August 2013

Due to its excellent bioactivity, 45S5 Bioglass® is being highly considered in tissue engineering scaffold development. In order to enhance vascularization promoting tissue growth, these scaffolds typically have a highly interconnected porous structure with a porosity between 80 and >90%. Often, Bioglass®‐based scaffolds of such a high porosity have insufficient stiffness. In order to increase the stiffness of Bioglass®‐based scaffolds fabricated by the foam replica method, the herein investigated scaffolds were coated with a number of different biopolymers, including: collagen, gelatin, polycaprolactone (PCL), alginate and poly(l‐lactic acid). The resulting stiffness gain was quantified by means of ultrasonic measurements. Accordingly, PCL and collagen coatings increased the scaffold stiffness, as compared to uncoated scaffolds, by 58 and 38%, respectively; while no remarkable stiffness increase was recorded for the other coatings. Additionally, scanning electron microscopy images of polymer coated scaffolds revealed that PCL coatings had not clogged the scaffold's micropores, which is deemed essential for cell seeding and to enable in‐growth of bone tissue. Thus, the application of PCL coatings represents a promising strategy for mechanical competence enhancement of Bioglass®‐based scaffolds for bone tissue engineering.
Disseminated microsporidiosis in a renal transplant recipient: case report and review of the literature
Authors: Nagpal A. , Pritt B.S. , Lorenz E.C. , Amer H. , Nasr S.H. , Cornell L.D. , Iqbal S. , Wilhelm M.P.
Published: August 2013

Microsporidia are opportunistic pathogens that usually cause a limited disease in the gastrointestinal tract. Occasionally, they can cause disseminated disease. In solid organ transplant recipients, disseminated disease has been reported only rarely. We describe a 68‐year‐old woman who presented with fever, cough, and acute kidney injury 6 months after kidney transplantation. Dissemination was confirmed by identification of microsporidial spores in urine and bronchoalveolar lavage fluid. Polymerase chain reaction analysis identified the species as Encephalitozoon cuniculi.
Interaction between avoidance of photon absorption, excess energy dissipation and zeaxanthin synthesis against photooxidative stress in Arabidopsis
Authors: Cazzaniga Stefano , Dall' Osto Luca , Kong Sam‐Geun , Wada Masamitsu , Bassi Roberto
Published: August 2013

Plants evolved photoprotective mechanisms in order to counteract the damaging effects of excess light in oxygenic environments. Among them, chloroplast avoidance and non‐photochemical quenching concur in reducing the concentration of chlorophyll excited states in the photosynthetic apparatus to avoid photooxidation. We evaluated their relative importance in regulating excitation pressure on photosystem II. To this aim, genotypes were constructed carrying mutations impairing the chloroplast avoidance response (phot2) as well as mutations affecting the biosynthesis of the photoprotective xanthophyll zeaxanthin (npq1) or the activation of non‐photochemical quenching (npq4), followed by evaluation of their photosensitivity in vivo. Suppression of avoidance response resulted in oxidative stress under excess light at low temperature, while removing either zeaxanthin or PsbS had a milder effect. The double mutants phot2 npq1 and phot2 npq4 showed the highest sensitivity to photooxidative stress, indicating that xanthophyll cycle and qE have additive effects over the avoidance response. The interactions between non‐photochemical quenching and avoidance responses were studied by analyzing the kinetics of fluorescence decay and recovery at different light intensities. phot2 fluorescence decay lacked a component, here named as qM. This kinetic component linearly correlated with the leaf transmittance changes due to chloroplast relocation induced by white light and was absent when red light was used as actinic source. On these basis we conclude that a decrease in leaf optical density affects the apparent non‐photochemical quenching (NPQ) rise kinetic. Thus, excess light‐induced fluorescence decrease is in part due to avoidance of photon absorption rather than to a genuine quenching process.
Computational Fluid Dynamics Thermohydrodynamic Analysis of Three-Dimensional Sector-Pad Thrust Bearings With Rectangular Dimples
Authors: Papadopoulos C. I. , Kaiktsis L. , Fillon M.
Published: August 2013

The paper presents a detailed computational study of flow patterns and performance indices in a dimpled parallel thrust bearing. The bearing consists of eight pads; the stator surface of each pad is partially textured with rectangular dimples, aiming at maximizing the load carrying capacity. The bearing tribological performance is characterized by means of computational fluid dynamics (CFD) simulations, based on the numerical solution of the Navier–Stokes and energy equations for incompressible flow. Realistic boundary conditions are implemented. The effects of operating conditions and texture design are studied for the case of isothermal flow. First, for a reference texture pattern, the effects of varying operating conditions, in particular minimum film thickness (thrust load), rotational speed and feeding oil pressure are investigated. Next, the effects of varying texture geometry characteristics, in particular texture zone circumferential/radial extent, dimple depth, and texture density on the bearing performance indices (load carrying capacity, friction torque, and friction coefficient) are studied, for a representative operating point. For the reference texture design, the effects of varying operating conditions are further investigated, by also taking into account thermal effects. In particular, adiabatic conditions and conjugate heat transfer at the bearing pad are considered. The results of the present study indicate that parallel thrust bearings textured by proper rectangular dimples are characterized by substantial load carrying capacity levels. Thermal effects may significantly reduce load capacity, especially in the range of high speeds and high loads. Based on the present results, favorable texture designs can be assessed.
Analysis of Short-Term Energy Storage for Midsize Hydrostatic Wind Turbine1
Authors: Dutta Rahul , Wang Feng , Bohlmann Bradley F. , Stelson Kim A.
Published: August 2013

This paper presents a novel method of capturing more energy from the wind using short-term energy storage in a hydrostatic wind turbine. A hydrostatic transmission (HST) not only provides reliable operation but also enables energy management features like energy regeneration using hydraulic accumulators. In this study, turbulence-induced wind transients occurring near the rated power are exploited to extract more energy from the wind. Wind characteristics are analyzed to develop models to quantify the energy losses due to the wind turbulence and the potential energy gains from the short-term energy storage. A dynamic simulation model of the hydrostatic wind turbine and the proposed energy storage system is developed. A rule-based control strategy for the energy storage is proposed. Results show that in a 50 kW hydrostatic wind turbine, the annual energy production (AEP) can be increased by 4.1% with a 60 liter hydraulic accumulator.
Field emission properties of carbon nanotube emitters dependent on electrode geometry
Authors: Song Yenan , Hoon Shin Dong , Jeon Seok-Gy , Kim Jung-Il , Jin Lee Cheol
Published: August 2013

Field emission properties of carbon nanotube (CNT) emitters dependent on electrode geometry have been systematically studied using two different types of diode electrode configurations. The experimental and simulation results clearly reveal that field emission properties, such as emission current and long-term emission stability, are strongly influenced by the geometry of the electrode configuration. The enhanced local electric field at the periphery of CNT emitters results in high local edge emissions that severely degrade emission current during long-term emission stability test and reduce the emission current density before electrical breakdown.
Accurate semiautomatic assessment of ligament length variations from MRI data
Authors: Honal Matthias , Lovell‐Smith Cris , Vicari Marco , Weitzel Elisabeth , Izadpanah Kaywan , Weigel Matthias
Published: August 2013

Purpose:

A semiautomatic method for the assessment of ligament length variations during different joint positions based on MRI data is proposed.

Methods:

Ligament lengths are represented as distances between points marking characteristic locations in the ligament insertion regions on the bones. These points are defined manually for one single reference joint position and for all other joint positions they are automatically mapped with high accuracy to the correct locations using image registration methods. The methodology is validated using data from 16 volunteers depicting the coracoclavicular ligaments in the left shoulder during different arm abductions.

Results:

The method yielded a superior reproducibility of the point locations over different joint positions compared to manual point marking. Significant ligament length variations were found for different abductions which was not possible with manual measurements. Acquisition related geometric distortions and inaccuracies during the registration and segmentation process were small.

Conclusions:

The proposed method provides superior accuracy for thein vivo analysis of ligament dynamics compared to manual measurements. This permits a better understanding of the ligament behavior during joint motion and offers new possibilities for presurgical planning which to date has not been possible with manual data analysis.
Slow Earthquakes, Preseismic Velocity Changes, and the Origin of Slow Frictional Stick-Slip
Authors: Kaproth Bryan M. , Marone C.
Published: August 2013

Slow Stick-Slip

While the character of slow earthquakes has been approximated for some time, precise slip histories and the underlying mechanisms have remained elusive.
Kaproth and Marone
(p.
1229
; published online 15 August) have made laboratory observations of repetitive, slow stick-slip in fault-zone materials and developed a mechanical explanation for how earthquake-like dynamic slip nucleation could start and then arrest so as to produce slow slip. As preseismic slip is a precursor to rupture, temporal variations in elastic wave speeds should be monitored in regions of high seismic hazard.
Complete Genome Sequences of Newcastle Disease Virus Strains Isolated from Three Different Poultry Species in China
Authors: Wang Xuan , Gong Zheng , Zhao Lei , Wang Jian , Sun Gege , Liu Yali , Tao Peipei , Zhang Huaikang , Li Shangde , Jiang Fei , Hu Yuanqing , Zhang Xunhai
Published: August 2013

In 2000, three Newcastle disease virus (NDV) strains were isolated from outbreaks of infection in layers, ducklings, and geese in the same region of China during the same time period. Here, we report their complete genome sequences, which belong to the NDV genotype VIId. This discovery might provide clues as to the evolution of the NDVs of different avian origins.
Complete Genome Sequence of Serratia liquefaciens Strain ATCC 27592
Authors: Nicholson Wayne L. , Leonard Michael T. , Fajardo-Cavazos Patricia , Panayotova Nedka , Farmerie William G. , Triplett Eric W. , Schuerger Andrew C.
Published: August 2013

We report the complete genome sequence of
Serratia liquefaciens
strain ATCC 27592, which was previously identified as capable of growth under low-pressure conditions. To the best of our knowledge, this is the first announcement of the complete genome sequence of an
S. liquefaciens
strain.
Complete Genome Sequence of
emm
Type 14 Streptococcus pyogenes Strain HSC5
Authors: Port Gary C. , Paluscio Elyse , Caparon Michael G.
Published: August 2013

Streptococcus pyogenes
causes a greater diversity of human disease than any other bacterial pathogen. Here, we present the complete genome sequence of the
emm
type 14
S. pyogenes
strain HSC5. This strain is a robust producer of the cysteine protease SpeB and is capable of producing infection in several different animal models.
Draft Genome Sequences for Three Mercury-Methylating, Sulfate-Reducing Bacteria
Authors: Brown Steven D. , Hurt Richard A. , Gilmour Cynthia C. , Elias Dwayne A.
Published: August 2013

The genetic basis for bacterial mercury methylation has been described recently. For insights into the physiology of mercury-methylating bacteria, we present genome sequences for
Desulfococcus multivorans
strain DSM 2059,
Desulfovibrio alkalitolerans
strain DSM 16529, and
Desulfovibrio
species strain X2.
Transverse colon perforation due to carcinoma rectum: an unusual presentation against Laplace's law
Authors: Sahoo Manash Ranjan , Kumar Anil , Jaiswal Sunil , C Basavaraja
Published: August 2013

We present a case of distal large bowel obstruction, in the setting of a competent ileocaecal valve, the caecum is the most common site of perforation (for Laplace's law). We describe a case of obstruction at the rectum due to constricting carcinomatous growth, presenting with perforation of transverse colon (against Laplace's law). A 60-year-old women presented to the emergency department with acute abdominal pain. The pain was preceded by 3 days of intestinal obstruction. Clinically there was guarding and rigidity. Straight X-ray of the abdomen revealed free gas under diaphragm. Surgical exploration revealed transverse colon perforation with carcinoma of rectum. Loop transverse colostomy was performed as the patient was very sick. The patient improved slowly in the intensive care unit. To conclude, even though the caecum is the most common site for perforation in case of distal obstruction, perforation of transverse colon can occur otherwise as a unique presentation.
A complicated case of altered sensorium
Authors: Vikram Kushaal , KN Shivashankara , Chakraborty Joydeep , Umakanth Shashikiran
Published: August 2013

Tuberculosis and malaria are two common diseases afflicting the population of the Indian subcontinent. Both are associated with fatal neurological complications. Clinically, it may be difficult to differentiate between the two, except for that the focal neurological complications are more common with central nervous system (CNS) tuberculosis than with cerebral malaria. We report the case of a 48-year-old woman who presented with a history of fever and altered sensorium of short duration. She was initially treated for falciparum malaria on the basis of positive peripheral smear and normal CT scan of the brain, but later on diagnosed to have CNS tuberculosis on the basis of persistence of symptoms, development of focal neurological symptoms and MRI of the brain showing multiple tuberculomas. She improved significantly with a course of antitubercular treatment (ATT) and systemic corticosteroids.
Fatal upper gastrointestinal bleed arising from duodenal varices secondary to undiagnosed portal hypertension
Authors: Larson John V , Steensma Elizabeth A , Burke Leandra H , Bartholomew David M
Published: August 2013

Duodenal varices are an unexpected source of upper gastrointestinal haemorrhage associated with high mortality. The prevalence of ectopic variceal bleeding accounts for 2–5% of all variceal bleeding; of this, only 17% occurs in the duodenum. Diagnosis is difficult, and insufficient evidence exists to demonstrate the best treatment option when haemorrhage occurs. We report the case of a 69-year-old man with a history of chronic alcoholism who presented to the emergency department (ED) with nausea, vomiting and several episodes of haematochezia. Diagnostic workup in the ED included CT with multiplanar reconstruction, which revealed a network of large tortuous blood vessels running near the second portion of the duodenum between the inferior vena cava and portal vein. The patient was emergently treated with endoscopic therapy and clipping of the vessel. This failed, and he was subsequently taken to the operating room for suture ligation of the bleeding duodenal varices.
Curcumin protects rat heart mitochondria against anoxia–reoxygenation induced oxidative injury
Authors: Xu PeiHan , Yao YaLi , Guo PengJun , Wang Ting , Yang BingWu , Zhang Zheng
Published: August 2013

It is an important therapeutic strategy to protect mitochondria from oxidative stress, especially during ischemia–reperfusion. Curcumin is a naturally occurring phenolic compound isolated as a yellow pigment from turmeric (Curcuma longa). This compound has received much attention due to its diversity of biological and pharmacological activities. In this study, an attempt has been made to evaluate the protective effects of curcumin on rat heart mitochondrial injuries induced by in vitro anoxia–reoxygenation. It was found that curcumin added before anoxia or immediately prior to reoxygenation exhibited remarkable protective effects against anoxia–reoxygenation induced oxidative damage to mitochondria, in concentrations ranging from picomoles to micromoles, with EC50s in the nanomolar range. The protective effects include inhibition of the decrease of state 3 respiratory activity, the decrease of respiratory control ratio (RCR) and ADP:oxygen (ADP:O) ratio, as well as the increase of state 4 respiratory activity; inhibition of the decrease of the membrane fluidity; inhibition of lipoperoxidation and protein carbonylation; as well as inhibition of the enhanced release of cardiolipin (CL) and cytochrome c (Cyt c). These results demonstrate the superior antioxidative properties of curcumin, and make it a promising candidate for the prevention and (or) therapy for ischemia–reperfusion injuries and the related free radical initiated diseases.
VISCOUS DARK ENERGY IN f(T) GRAVITY
Authors: SHARIF M. , RANI SHAMAILA
Published: August 2013

We study the bulk viscosity taking dust matter in the generalized teleparallel gravity. We consider different dark energy (DE) models in this scenario along with a time-dependent viscous model to construct the viscous equation of state (EoS) parameter for these DE models. We discuss the graphical representation of this parameter to investigate the viscosity effects on the accelerating expansion of the universe. It is mentioned here that the behavior of the universe depends upon the viscous coefficients showing the transition from decelerating to accelerating phase. It leads to the crossing of phantom divide line and becomes phantom dominated for specific ranges of these coefficients.
NOX2 interacts with podocyte TRPC6 channels and contributes to their activation by diacylglycerol: essential role of podocin in formation of this complex
Authors: Kim Eun Young , Anderson Marc , Wilson Cory , Hagmann Henning , Benzing Thomas , Dryer Stuart E.
Published: August 2013

Canonical transient receptor potential-6 (TRPC6) channels have been implicated in the pathophysiology of glomerular diseases. TRPC6 channels are typically activated by diacylglycerol (DAG) during PLC-dependent transduction cascades. TRPC6 channels can also be activated by reactive oxygen species (ROS). We previously showed that podocin is required for DAG analogs to produce robust activation of TRPC6 channels in podocytes. Here we show that endogenous TRPC6 channels in immortalized podocytes reciprocally coimmunoprecipitate with the catalytic subunit of the NADPH oxidase NOX2 (gp91phox). The NOX2-TRPC6 interaction was not detected in cells stably expressing a short hairpin RNA targeting podocin, although NOX2 and TRPC6 were present at normal levels. Application of a membrane-permeable DAG analog [1-oleoyl-2-acetyl- sn-glycerol (OAG)] increased generation of ROS in podocytes, but this effect was not detected in podocin knockdown cells. OAG also increased steady-state surface expression of the NOX2 regulatory subunit p47phox. In whole cell recordings, TRPC6 activation by OAG was reduced in podocytes pretreated with the NOX2 inhibitor apocynin, by the pan-NOX inhibitor diphenylene iodonium, and by tempol, a ROS quencher. Cholesterol depletion and disruption of lipid rafts by methyl-β-cyclodextrin reduced activation of podocyte TRPC6 channels by OAG and also eliminated the NOX2-TRPC6 interaction as assessed by coimmunoprecipitation. These data suggest that active NOX2 assembles with TRPC6 at podocin-organized sterol-rich raft domains and becomes catalytically active in response to DAG. The localized production of ROS contributes to TRPC6 activation by chemical stimuli such as DAG. Podocin appears to be necessary for assembly of the NOX2-TRPC6 complex in lipid rafts.
Oxygen governs Galβ1–3GalNAc epitope in human placenta
Authors: Ermini Leonardo , Bhattacharjee Jayonta , Spagnoletti Antonella , Bechi Nicoletta , Aldi Silvia , Ferretti Cristina , Bianchi Laura , Bini Luca , Rosati Floriana , Paulesu Luana , Ietta Francesca
Published: August 2013

It is becoming increasingly apparent that the dynamics of glycans reflect the physiological state of cells involved in several cell functions including growth, response to signal molecules, migration, as well as adhesion to, interaction with, and recognition of other cells. The presence of glycoconjugates in human placenta suggests their major role in maternal-fetal exchanges, intercellular adhesion, cellular metabolism, and villous vessel branching. Although several studies have described glycoconjugate distribution in the human placenta descriptions of their physiological function and control mechanisms during placental development are lacking. In this study we investigated the developmental distribution and regulation of placental core 1 O- and N-glycans focusing on early and late first trimester human pregnancy. To define the control mechanisms of the oligosaccharide chains during early placentation process, chorionic villous explants and human trophoblast cell lines were exposed to various oxygen levels. We found that oxygen tension regulates changes in core-1 O-glycan (the disaccharide Galβ1–3GalNAc) epitope expression levels. Moreover, by double affinity chromatography and subsequent analysis with mass spectrometry, we identified in the heat shock protein 90-α (HSP90α) a good candidate as carrier of the Galβ1–3GalNAc epitope at low oxygen tension. Our results support a fundamental role of oxygen tension in modulating glycosylation of proteins during placental development.
Increase in parasympathetic tone by pyridostigmine prevents ventricular dysfunction during the onset of heart failure
Authors: Lataro Renata M. , Silva Carlos A. A. , Fazan Rubens , Rossi Marcos A. , Prado Cibele M. , Godinho Rosely O. , Salgado Helio C.
Published: August 2013

Heart failure (HF) is characterized by elevated sympathetic activity and reduced parasympathetic control of the heart. Experimental evidence suggests that the increase in parasympathetic function can be a therapeutic alternative to slow HF evolution. The parasympathetic neurotransmission can be improved by acetylcholinesterase inhibition. We investigated the long-term (4 wk) effects of the acetylcholinesterase inhibitor pyridostigmine on sympathovagal balance, cardiac remodeling, and cardiac function in the onset of HF following myocardial infarction. Myocardial infarction was elicited in adult male Wistar rats. After 4 wk of pyridostigmine administration, per os, methylatropine and propranolol were used to evaluate the cardiac sympathovagal balance. The tachycardic response caused by methylatropine was considered to be the vagal tone, whereas the bradycardic response caused by propranolol was considered to be the sympathetic tone. In conscious HF rats, pyridostigmine reduced the basal heart rate, increased vagal, and reduced sympathetic control of heart rate. Pyridostigmine reduced the myocyte diameter and collagen density of the surviving left ventricle. Pyridostigmine also increased vascular endothelial growth factor protein in the left ventricle, suggesting myocardial angiogenesis. Cardiac function was assessed by means of the pressure-volume conductance catheter system. HF rats treated with pyridostigmine exhibited a higher stroke volume, ejection fraction, cardiac output, and contractility of the left ventricle. It was demonstrated that the long-term administration of pyridostigmine started right after coronary artery ligation augmented cardiac vagal and reduced sympathetic tone, attenuating cardiac remodeling and left ventricular dysfunction during the progression of HF in rats.
Contribution of nitric oxide to brachial artery vasodilation during progressive handgrip exercise in the elderly
Authors: Trinity Joel D. , Wray D. Walter , Witman Melissa A. H. , Layec Gwenael , Barrett-O'Keefe Zachary , Ives Stephen J. , Conklin Jamie D. , Reese Van , Richardson Russell S.
Published: August 2013

The reduction in nitric oxide (NO)-mediated vascular function with age has largely been determined by flow-mediated dilation (FMD). However, in light of recent uncertainty surrounding the NO dependency of FMD and the recognition that brachial artery (BA) vasodilation during handgrip exercise is predominantly NO-mediated in the young, we sought to determine the contribution of NO to BA vasodilation in the elderly using the handgrip paradigm. BA vasodilation during progressive dynamic (1 Hz) handgrip exercise performed at 3, 6, 9, and 12 kg was assessed with and without NO synthase (NOS) inhibition [intra-arterial NG-monomethyl-l-arginine (l-NMMA)] in seven healthy older subjects (69 ± 2 yr). Handgrip exercise in the control condition evoked significant BA vasodilation at 6 (4.7 ± 1.4%), 9 (6.5 ± 2.2%), and 12 kg (9.5 ± 2.7%). NOS inhibition attenuated BA vasodilation, as the first measurable increase in BA diameter did not occur until 9 kg (4.0 ± 1.8%), and the change in BA diameter at 12 kg was reduced by ∼30% (5.1 ± 2.2%), with unaltered shear rate (Control: 407 ± 57, l-NMMA: 427 ± 67 s−1). Although shifted downward, the slope of the relationship between BA diameter and shear rate during handgrip exercise was unchanged (Control: 0.0013 ± 0.0004, l-NMMA: 0.0011 ± 0.007, P = 0.6) as a consequence of NOS inhibition. Thus, progressive handgrip exercise in the elderly evokes a robust BA vasodilation, the magnitude of which was only minimally attenuated following NOS inhibition. This modest contribution of NO to BA vasodilation in the elderly supports the use of the handgrip exercise paradigm to assess NO-dependent vasodilation across the life span.
Changes in circulating microRNAs levels with exercise modality
Authors: Banzet Sébastien , Chennaoui Mounir , Girard Olivier , Racinais Sébastien , Drogou Catherine , Chalabi Hakim , Koulmann Nathalie
Published: August 2013

Here, we studied muscle-specific and muscle-related miRNAs in plasma of exercising humans. Our aim was to determine whether they are affected by eccentric and/or concentric exercise modes and could be biomarkers of muscle injuries or possible signaling molecules. On two separate days, nine healthy subjects randomly performed two 30-min walking exercises, one downhill (high eccentric component) and one uphill (high concentric component). Perceived exertion and heart rate were higher during the uphill exercise, while subjective pain and ankle plantar flexor strength losses within the first 48-h were higher following the downhill exercise. Both exercises increased serum creatine kinase and myoglobin with no significant differences between conditions. Plasma levels of circulating miRNAs assessed before, immediately after, and at 2-, 6-, 24-, 48-, and 72-h recovery showed that 1) hsa-mir-1, 133a, 133b, and 208b were not affected by concentric exercise but significantly increased during early recovery of eccentric exercise (2 to 6 h); 2) hsa-mir-181b and 214 significantly and transiently increased immediately after the uphill, but not downhill, exercise. The muscle-specific hsa-mir-206 was not reliably quantified and cardiac-specific hsa-mir-208a remained undetectable. In conclusion, changes in circulating miRNAs were dependent on the exercise mode. Circulating muscle-specific miRNAs primarily responded to a downhill exercise (high eccentric component) and could potentially be alternative biomarkers of muscle damage. Two muscle-related miRNAs primarily responded to an uphill exercise (high exercise intensity), suggesting they could be markers or mediators of physiological adaptations.
Time and volume dependence of dead space in healthy and surfactant-depleted rat lungs during spontaneous breathing and mechanical ventilation
Authors: Dassow Constanze , Schwenninger David , Runck Hanna , Guttmann Josef
Published: August 2013

Volumetric capnography is a standard method to determine pulmonary dead space. Hereby, measured carbon dioxide (CO2) in exhaled gas volume is analyzed using the single-breath diagram for CO2. Unfortunately, most existing CO2 sensors do not work with the low tidal volumes found in small animals. Therefore, in this study, we developed a new mainstream capnograph designed for the utilization in small animals like rats. The sensor was used for determination of dead space volume in healthy and surfactant-depleted rats ( n = 62) during spontaneous breathing (SB) and mechanical ventilation (MV) at three different tidal volumes: 5, 8, and 11 ml/kg. Absolute dead space and wasted ventilation (dead space volume in relation to tidal volume) were determined over a period of 1 h. Dead space increase and reversibility of the increase was investigated during MV with different tidal volumes and during SB. During SB, the dead space volume was 0.21 ± 0.14 ml and increased significantly at MV to 0.39 ± 0.03 ml at a tidal volume of 5 ml/kg and to 0.6 ± 0.08 ml at a tidal volume of 8 and 11 ml/kg. Dead space and wasted ventilation during MV increased with tidal volume. This increase was mostly reversible by switching back to SB. Surfactant depletion had no further influence on the dead space increase during MV, but impaired the reversibility of the dead space increase.
Development and validation of anthropometric prediction equations for estimation of lean body mass and appendicular lean soft tissue in Indian men and women
Authors: Kulkarni Bharati , Kuper Hannah , Taylor Amy , Wells Jonathan C. , Radhakrishna K. V. , Kinra Sanjay , Ben-Shlomo Yoav , Smith George Davey , Ebrahim Shah , Byrne Nuala M. , Hills Andrew P.
Published: August 2013

Lean body mass (LBM) and muscle mass remain difficult to quantify in large epidemiological studies due to the unavailability of inexpensive methods. We therefore developed anthropometric prediction equations to estimate the LBM and appendicular lean soft tissue (ALST) using dual-energy X-ray absorptiometry (DXA) as a reference method. Healthy volunteers ( n = 2,220; 36% women; age 18-79 yr), representing a wide range of body mass index (14–44 kg/m2), participated in this study. Their LBM, including ALST, was assessed by DXA along with anthropometric measurements. The sample was divided into prediction (60%) and validation (40%) sets. In the prediction set, a number of prediction models were constructed using DXA-measured LBM and ALST estimates as dependent variables and a combination of anthropometric indices as independent variables. These equations were cross-validated in the validation set. Simple equations using age, height, and weight explained >90% variation in the LBM and ALST in both men and women. Additional variables (hip and limb circumferences and sum of skinfold thicknesses) increased the explained variation by 5–8% in the fully adjusted models predicting LBM and ALST. More complex equations using all of the above anthropometric variables could predict the DXA-measured LBM and ALST accurately, as indicated by low standard error of the estimate (LBM: 1.47 kg and 1.63 kg for men and women, respectively), as well as good agreement by Bland-Altman analyses (Bland JM, Altman D. Lancet 1: 307–310, 1986). These equations could be a valuable tool in large epidemiological studies assessing these body compartments in Indians and other population groups with similar body composition.
BRD4 Sustains Melanoma Proliferation and Represents a New Target for Epigenetic Therapy
Authors: Segura Miguel F. , Fontanals-Cirera Bárbara , Gaziel-Sovran Avital , Guijarro María V. , Hanniford Doug , Zhang Guangtao , González-Gomez Pilar , Morante Marta , Jubierre Luz , Zhang Weijia , Darvishian Farbod , Ohlmeyer Michael , Osman Iman , Zhou Ming-Ming , Hernando Eva
Published: August 2013

Metastatic melanoma remains a mostly incurable disease. Although newly approved targeted therapies are efficacious in a subset of patients, resistance and relapse rapidly ensue. Alternative therapeutic strategies to manipulate epigenetic regulators and disrupt the transcriptional program that maintains tumor cell identity are emerging. Bromodomain and extraterminal domain (BET) proteins are epigenome readers known to exert key roles at the interface between chromatin remodeling and transcriptional regulation. Here, we report that BRD4, a BET family member, is significantly upregulated in primary and metastatic melanoma tissues compared with melanocytes and nevi. Treatment with BET inhibitors impaired melanoma cell proliferation in vitro and tumor growth and metastatic behavior in vivo, effects that were mostly recapitulated by individual silencing of BRD4. RNA sequencing of BET inhibitor–treated cells followed by Gene Ontology analysis showed a striking impact on transcriptional programs controlling cell growth, proliferation, cell-cycle regulation, and differentiation. In particular, we found that, rapidly after BET displacement, key cell-cycle genes (SKP2, ERK1, and c-MYC) were downregulated concomitantly with the accumulation of cyclin-dependent kinase (CDK) inhibitors (p21 and p27), followed by cell-cycle arrest. Importantly, BET inhibitor efficacy was not influenced by BRAF or NRAS mutational status, opening the possibility of using these small-molecule compounds to treat patients for whom no effective targeted therapy exists. Collectively, our study reveals a critical role for BRD4 in melanoma tumor maintenance and renders it a legitimate and novel target for epigenetic therapy directed against the core transcriptional program of melanoma. Cancer Res; 73(20); 6264–76. ©2013 AACR.