bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanism and implications of CXCR4‐mediated integrin activation by Porphyromonas gingivalis
Authors: Hajishengallis G. , McIntosh M.L. , Nishiyama S.‐I. , Yoshimura F. 
Published: December 2012

SummaryIn monocytes and macrophages, the interaction of Porphyromonas gingivalis with Toll‐like receptor 2 (TLR2) leads to the activation of a MyD88‐dependent antimicrobial pathway and a phosphatidylinositol‐3 kinase (PI3K) ‐dependent pro‐adhesive pathway, which activates the β2‐integrin complement receptor 3 (CR3). By means of its fimbriae, P. gingivalis binds CXC‐chemokine receptor 4 (CXCR4) and induces crosstalk with TLR2 that inhibits the MyD88‐dependent antimicrobial pathway. In this paper, we investigated the impact of the P. gingivalis‐CXCR4 interaction on the pro‐adhesive pathway. Using human monocytes, mouse macrophages, or receptor‐transfected cell lines, we showed that the binding of P. gingivalis fimbriae to CXCR4 induces CR3 activation via PI3K, albeit in a TLR2‐independent manner. An isogenic strain of P. gingivalis expressing mutant fimbriae that do not interact with CXCR4 failed to efficiently activate CR3, leading to enhanced susceptibility to killing in vivo compared with the wild‐type organism. This in vivo observation is consistent with previous findings that activated CR3 mediates safe entry of P. gingivalis into macrophages. Taken together with our previous work, these results indicate that the interaction of P. gingivalis with CXCR4 leads to inhibition of antimicrobial responses and enhancement of pro‐adhesive responses, thereby maximizing its adaptive fitness in the mammalian host.
KCa3.1 channel downregulation and impaired endothelium‐derived hyperpolarization‐type relaxation in pulmonary arteries from chronically hypoxic rats
Authors: Kroigaard Christel , Kudryavtseva Olga , Dalsgaard Thomas , Wandall‐Frostholm Christine , Olesen Søren‐Peter , Simonsen Ulf 
Published: December 2012

New Findings
What is the central question of this study?Do the function and expression of small (KCa2) and intermediate (KCa3.1) conductance calcium‐activated potassium channels increase as a compensatory mechanism to counteract hypoxia‐induced pulmonary hypertension in rats?
What is the main finding and its importance?Our findings provide evidence for impaired endothelium‐derived hyperpolarization‐type relaxation in chronically hypoxic pulmonary small arteries despite upregulation of KCa2.3 channels. Our findings suggest that KCa3.1 channels are important for the maintenance of endothelium‐derived hyperpolarization‐type relaxation.
Calcium‐activated potassium channels of small (KCa2, SK) and intermediate (KCa3.1, IK) conductance are involved in endothelium‐dependent relaxation of pulmonary arteries. We hypothesized that the function and expression of KCa2 and KCa3.1 increase as a compensatory mechanism to counteract hypoxia‐induced pulmonary hypertension in rats. For functional studies, pulmonary arteries were mounted in microvascular myographs for isometric tension recordings. The KCa channel expression was evaluated by immunoblotting and quantitative PCR. Although ACh induced similar relaxations, the ACh‐induced relaxations were abolished by the combined inhibition of nitric oxide synthase (by l‐nitro‐arginine, l‐NOARG), cyclo‐oxygenase (by indomethacin) and soluble guanylate cyclase (by ODQ) in pulmonary arteries from hypoxic rats, whereas 20 ± 6% (n= 8) maximal relaxation in response to ACh persisted in arteries from normoxic rats. Inhibiting Na+,K+‐ATPase with ouabain or blocking KCa2 and KCa3.1 channels reduced the persisting ACh‐induced relaxation. In the presence of l‐NOARG and indomethacin, a novel KCa2 and KCa3.1 channel activator, NS4591, induced concentration‐ and endothelium‐dependent relaxations, which were markedly reduced in arteries from chronically hypoxic rats compared with arteries from normoxic rats. The mRNA levels of KCa2.3 and KCa3.1 were unaltered, whereas KCa2.3 protein expression was upregulated and KCa3.1 protein expression downregulated in pulmonary arteries from rats exposed to hypoxia. In conclusion, endothelium‐dependent relaxation was conserved in pulmonary arteries from chronically hypoxic rats, while endothelium‐derived hyperpolarization (EDH)‐type relaxation was impaired in chronically hypoxic pulmonary small arteries despite upregulation of KCa2.3 channels. Since impaired EDH‐type relaxation was accompanied by KCa3.1 channel protein downregulation, these findings suggest that KCa3.1 channels are important for the maintenance of EDH‐type relaxation.
Effects of dietary history on energy metabolism and physiological parameters in C57BL/6J mice
Authors: Hoevenaars Femke P. M. , Keijer Jaap , Swarts Hans J. , Snaas‐Alders Sophie , Bekkenkamp‐Grovenstein Melissa , van Schothorst Evert M. 
Published: December 2012

New Findings
What is the central question of this study?Do intake patterns of diets with a different energy content have a lasting effect on body weight persistence?
What is the main finding and its importance?After switches between semi‐purified diets differing only in the fat‐to‐sugar ratio, the last consumed diet determined the energy intake, energy expenditure, body weight, body fat stores, circulating hormones and metabolites in C57BL/6J mice. In contrast with persistent effects observed in studies using diets with different ingredients, suggesting diet‐induced set points, this study shows that body weight and metabolic parameters ‘settle’ based on current energetic input and output. This supports the settling point theory and underlines the importance of the choice of diet in physiological studies.
Understanding body weight regulation is essential to fight obesity. Mouse studies, using different types of diets, showed conflicting results in terms of body weight persistence after changing from an ad libitum high‐fat diet to an ad libitum low‐fat diet. In this study, we questioned specifically whether the energy content of the diet has a lasting effect on energy balance and body weight, using multiple switches and two purified diets with a different fat‐to‐sugar ratio, but otherwise identical ingredients. Young‐adult obesity‐prone male C57BL/6J mice were fed single or double switches of semi‐purified diets with either 10 energy % (en%) fat (LF) or 40en% fat (HF), with starch replaced by fat, while protein content remained equal. After none, one or two dietary changes, energy metabolism was assessed at 5, 14 and 19 weeks. We observed no systematic continuous compensation in diet and energy intake when returning to LF after HF consumption. Body weight, white adipose tissue mass and histology, serum metabolic parameters, energy expenditure and substrate usage all significantly reflected the current diet intake, independent of dietary changes. This contrasts with studies that used diets with different ingredients and showed persistent effects of dietary history on body weight, suggesting diet‐dependent metabolic set points. We conclude that body weight and metabolic parameters ‘settle’, based on current energetic input and output. This study also highlights the importance of considering the choice of diet in physiological and metabolic intervention studies.
Intracoronary secretin increases cardiac perfusion and function in anaesthetized pigs through pathways involving β‐adrenoceptors and nitric oxide
Authors: Grossini Elena , Molinari Claudio , Morsanuto Vera , Mary David A. S. G , Vacca Giovanni 
Published: December 2012

New Findings
What is the central question of this study?What is the primary effect of secretin on cardiac function and perfusion? Are the autonomic nervous system, secretin receptors and NO involved?
What is the main finding and its importance?Intracoronary secretin increases cardiac perfusion and function through β‐adrenoceptors and secretin receptors in the anaesthetized pig, with the coronary vasodilatation involving NO release. As downstream effectors of the observed NO production, cAMP/protein kinase A and phosphoinositide 3‐kinase/Akt‐related signalling were found. Thus, secretin could play an important role in the modulation of cardiovascular reflexes elicited by stimulation of gastrointestinal mechano/chemoreceptors. Moreover, secretin could hypothetically have a potential use in the treatment of acute left ventricular failure or ischaemic heart disease.
Secretin has been implicated in cardiovascular regulation through its specific receptors, as well as through β‐adrenoceptors and nitric oxide, although data on its direct effect on coronary blood flow and cardiac function have remained scarce. The present study aimed to determine the primary in vivo effect of secretin on cardiac function and perfusion and the mechanisms related to the autonomic nervous system, secretin receptors and NO. In addition, in coronary endothelial cells the intracellular pathways involved in the effects of secretin on NO release were also examined. In 30 pigs, intracoronary secretin infusion at 2.97 pg for each millilitre per minute of coronary blood flow at constant heart rate and aortic blood pressure increased coronary blood flow, maximal rate of change of left ventricular pressure, segmental shortening, cardiac output and coronary NO release (P < 0.05). These responses were graded in a further five pigs. Moreover, while blockade of muscarinic cholinoreceptors (n= 5) and of α‐adrenoceptors (n= 5) did not abolish the observed responses to secretin, blockade of β1‐adrenoceptors (n= 5) prevented the effects of secretin on cardiac function. In addition, blockade of β2‐adrenoceptors (n= 5) and NO synthase inhibition (n= 5) prevented the coronary response and the effect of secretin on NO release. All these effects were abolished by a secretin receptor inhibitor (n= 5). In coronary endothelial cells, the increased NO production caused by secretin was found to be related to cAMP/protein kinase A signalling activated as downstream effectors of stimulation of secretin receptors and β2‐adrenoceptors. In conclusion, in anaesthetized pigs secretin primarily increased cardiac function and perfusion through the involvement of specific receptors, β‐adrenoceptors and NO release.
On Waves and Distributions in Population Dynamics
Authors: Vitanov Nikolay Kolev , Dimitrova Zlatinka Ivanova 
Published: December 2012

We discuss dynamics of spatially distributed interacting populations.В The following two cases are discussed: (I.) migration waves for the caseВ or negligible random fluctuations of the populations densities and (II.) probabilityВ distributions of the spatially averaged populations densities for the case ofsignificant random fluctuations of these densities. For each of the cases we obtainВ in general a system of differential equations that is treated analytically (when possible)В or numerically. The obtained results are discussed from the point of view of population dynamics.
The Art of Mathematical Biology: a Foreword for the Launch of BIOMATH
Authors: Schnell Santiago 
Published: December 2012

We cannot debate that the advances made over the past 30 years in molecular biology, biochemistry and cell biology have dramatically changed biology and the biomedical sciences. Academic institutions and funding agencies increasingly recognize the interdisciplinary nature of biology and medicine, including the important role mathematical, statistical and computational modeling play in the analysis and interpretation of data and information.В By and large, biologists and biomedical scientists appear to have more appreciation for mathematical biology research because they are increasingly attracted to discover new biological principles and mechanisms in collaboration with mathematicians.В . . .
From the Editor-in-Chief
Authors: Anguelov Roumen 
Published: December 2012

Interdisciplinary research involving mathematical and biological sciences has deep roots at the Bulgarian Academy of Sciences, established well before the contemporary terms of Mathematical Biology or Biomathematics were coined in. The father of Molecular Biology in Bulgaria, Rumen Tsanev, is also pioneer of Bio-Mathematical research at the Academy. His joint work with Blagovest Sendov in the nineteen sixties using mathematical modelling and computer simulation in studying the cellular proliferation, differentiation and carcinogenesis productively links new developments in both fields for further advancement of knowledge.В . . .В В В В В В В
The Role of Strain Rate Response on Tribological Behavior of
Metals
Authors: Menezes Pradeep L. , Kishore  , Kailas Satish V. , Lovell Michael R. 
Published: December 2012

Abstract
In an effort to study the role of strain rate response on the tribological behavior of metals, room temperature experiments were conducted by sliding commercially pure titanium and a-iron pins against an H-11 die steel flats of various surface textures. The steel flat surface textures were specifically prepared to allow for imposing varying amounts of strain rates at the contacting interface during sliding motion. In the experiments, it was observed that titanium (a harder material than iron) formed a transfer layer on H-11 steel surface textures that produced higher strain rates. In contrast, the titanium pins abraded the steel surfaces that produced lower strain rates. The iron pins were found to abrade the H-11 steel surface regardless of the surface texture characteristics. This unique tribological behavior of titanium is likely due to the fact that titanium undergoes adiabatic shear banding at high strain rates, which creates pathways for lower resistance shear planes. These shear planes lead to fracture and transfer layer formation on the surface of the steel flat, which ultimately promotes a higher strain rate of deformation at the asperity level. Iron does not undergo adiabatic shear banding and thus more naturally abrades the surfaces. Overall, the results clear indicated that a materials strain rate response can be an important factor in controlling the tribological behavior of a plastically deforming material at the asperity level.
Influence of Temperature, Medium, and Storage Duration on Chlamydia trachomatis DNA Detection by PCR
Authors: van Dommelen Laura , Wolffs Petra F. G. , van Tiel Frank H. , Dukers Nicole , Herngreen Selma B. , Bruggeman Cathrien A. , Hoebe Christian J. P. A. 
Published: December 2012

ABSTRACT

We validated the use of stored samples for
Chlamydia trachomatis
research.
C. trachomatis
DNA was detected by real-time PCR in clinical (urine and self-taken vaginal swabs) and spiked samples using six different media, five different time points (up to 2 years), and four different temperature conditions.
C. trachomatis
was detected in all 423 samples, and no clinically relevant degradation impact was detected.
Spinal dural arteriovenous malformation presented with intracranial hypertension in a young patient
Authors: Inci Mehmet Fatih , Senoğlu Mehmet , Ozkan Fuat , Yuksel Murvet 
Published: December 2012

Spinal dural arteriovenous malformations (AVM), the most common type of spinal cord vascular malformation, can be a challenge to diagnosis and prompt treatment. The disorder is rare, and the presenting clinical symptoms and signs are non-specific and insidious at onset. Spinal dural AVMs preferentially affect middle-aged men, and patients most commonly present with gait abnormality or lower-extremity weakness and sensory disturbances. İt may rarely present with symptoms of intracranial hypertension including headache and visual disorders.In this report, we present the radiological findings of a 19-year-old male patient with spinal dural AVM presenting with raised intracranial pressure symptoms including papilloedema and headache, and discuss with recent literature.
Prognostic factors for patellofemoral pain: a multicentre observational analysis
Authors: Collins Natalie J , Bierma-Zeinstra Sita M A , Crossley Kay M , van Linschoten Robbart L , Vicenzino Bill , van Middelkoop Marienke 
Published: December 2012

ObjectivesDescribe proportions of individuals with patellofemoral pain (PFP) with an unfavourable recovery over 12 months; identify clinical predictors of poor recovery at 3 and 12 months; and determine baseline values of predictors that identify those with poor 12-month prognosis.MethodsAn observational analysis utilised data from 310 individuals with PFP enrolled in two randomised clinical trials. Thirteen baseline variables (participant, PFP, study characteristics) were investigated for their prognostic ability. Pain, function and global recovery were measured at 3 and 12 months. Multivariate backward stepwise regression analyses (treatment-adjusted, p<0.10) were performed for each follow-up measure. Receiver operator characteristic curves identified cut-points associated with unfavourable recovery at 12 months.Results55% and 40% of participants had an unfavourable recovery at 3 and 12 months, respectively. Longer baseline pain duration was significantly associated with poor 3-month and 12-month recovery on measures of pain severity (β 11.36 to 24.94), Anterior Knee Pain (AKP) Scale (−4.44 to −11.33) and global recovery (OR: 2.32 to 6.11). Greater baseline pain severity and lower AKP Scale score were significantly associated with poor recovery on multiple measures (p<0.05). Baseline duration >2 months and AKP Scale score <70/100 were associated with unfavourable 12-month recovery.ConclusionsA substantial number of individuals with PFP have an unfavourable recovery over 12 months, irrespective of intervention. Knee pain duration >2 months is the most consistent prognostic indicator, followed by AKP Scale score <70. Sports medicine practitioners should utilise interventions with known efficacy in reducing PFP, and promote early intervention to maximise prognosis.Trial registrationAustralian study: Australian Clinical Trials Registry (ACTRN012605000463673), ClinicalTrials.gov (NCT00118521); Dutch study: International Standard Randomised Controlled Trial Number Register (ISRCTN83938749)
Do changes to the local street environment alter behaviour and quality of life of older adults? The ‘DIY Streets’ intervention
Authors: Ward Thompson Catharine , Curl Angela , Aspinall Peter , Alves Susana , Zuin Affonso 
Published: December 2012

BackgroundThe burden of ill-health due to inactivity has recently been highlighted. Better studies on environments that support physical activity are called for, including longitudinal studies of environmental interventions. A programme of residential street improvements in the UK (Sustrans ‘DIY Streets’) allowed a rare opportunity for a prospective, longitudinal study of the effect of such changes on older adults’ activities, health and quality of life.MethodsPre–post, cross-sectional surveys were carried out in locations across England, Wales and Scotland; participants were aged 65+ living in intervention or comparison streets. A questionnaire covered health and quality of life, frequency of outdoor trips, time outdoors in different activities and a 38-item scale on neighbourhood open space. A cohort study explored changes in self-report activity and well-being postintervention. Activity levels were also measured by accelerometer and accompanying diary records.ResultsThe cross-sectional surveys showed outdoor activity predicted by having a clean, nuisance-free local park, attractive, barrier-free routes to it and other natural environments nearby. Being able to park one's car outside the house also predicted time outdoors. The environmental changes had an impact on perceptions of street walkability and safety at night, but not on overall activity levels, health or quality of life. Participants’ moderate-to-vigorous activity levels rarely met UK health recommendations.ConclusionsOur study contributes to methodology in a longitudinal, pre–post design and points to factors in the built environment that support active ageing. We include an example of knowledge exchange guidance on age-friendly built environments for policy-makers and planners.
The accuracy of the olfactory sense in detecting alcohol intoxication in trauma patients
Authors: Malhotra Shweta , Kasturi Kannan , Abdelhak Nachama , Paladino Lorenzo , Sinert Richard 
Published: December 2012

IntroductionA common presentation to the emergency department (ED) is the trauma patient with altered sensorium who is presumed to be alcohol intoxicated by physicians based on their olfactory sense. ED physicians may often leave patients suspected of alcohol intoxication aside until the effects wear off, potentially missing trauma as the source of confusion. This often results in delays in diagnosing acute potentially life-threatening injuries in patients with presumed alcohol intoxication.ObjectiveThis study aimed to determine the accuracy of a physician's olfactory sense for diagnosing alcohol intoxication.MethodsPatients suspected of major trauma in the ED underwent an evaluation by the examining physician for alcohol odour and a blood alcohol level. Alcohol intoxication was defined as a serum ethanol level ≥80 mg/100 ml. Data were reported as means with 95% CI or proportions with IQR 25–75%.Results151 patients (70% men) were enrolled, with a median age of 45 years (IQR 33–56). The prevalence of alcohol intoxication was 43% (95% CI 35% to 51%).Operating CharacteristicsPhysician assessment of alcohol intoxication: sensitivity 84% (95% CI 73% to 92%), specificity 87% (95% CI 78% to 93%), positive likelihood ratio 6.6 (95% CI 3.8 to 11.6), negative likelihood ratio 0.18 (95% CI 0.1 to 0.3) and accuracy 86% (95% CI 80% to 91%). 7.3% (95% CI 4% to 13%) of patients were falsely suspected of being intoxicated.ConclusionsAlthough the physicians had a high degree of accuracy in identifying patients with alcohol intoxication based on their olfactory sense, they still falsely overestimated intoxication in significant numbers of non-intoxicated trauma patients.
What factors affect the success rate of the first attempt at endotracheal intubation in emergency departments?
Authors: Kim Changsun , Kang Hyung Goo , Lim Tae Ho , Choi Bo Youl , Shin Young-jeon , Choi Hyuk Joong 
Published: December 2012

Study objectiveThis study aimed to determine the factors associated with successful endotracheal intubation (ETI) on the first-attempt in an emergency department.MethodWe studied all of the ETI data at two urban emergency departments over a 5-year period. We assessed the intubator's specialty and training level, intubation method, device used, predicted airway difficulty and cause of ETIs. Univariate and multivariate logistic regression models were used to identify factors affecting the first-attempt success (FAS) of ETI in emergency departments.ResultsA total of 1478 adult ETIs were analysed. A multivariate logistic analysis revealed that factors such as a non-difficult airway (OR=5.11; 95% CI 3.38 to 7.72), senior physicians (2nd-year to 4th-year resident and attending physicians) (OR=2.39; 95% CI 1.61 to 3.55) and the rapid sequence intubation/induction (RSI) method (OR=2.06; 95% CI 1.04 to 3.03) had significant associations with the FAS for emergency medicine (EM) physicians. For non-EM physicians, however, a non-difficult airway was the only independent predictor of FAS (OR=3.10; 95% CI 1.82 to 5.28).ConclusionsThe predicted airway difficulty was the major factor associated with FAS in emergency department ETI on adults regardless of intubator's specialty. Especially in EM physician group, level of training and using of RSI also affecting on first–attempt success. The overall ETI success rate on first attempt was 80.1%, but EM physicians had success rate of 87.3%. Systematic technical and non-technical airway skill training focused on RSI and continuous quality control and ETI recording could help non-EM physicians increase their FAS rate.