bluuebunny/crossref_metadata_2025 huggingface dataset:
Cardiac oxytocin receptor blockade stimulates adverse cardiac remodeling in ovariectomized spontaneously hypertensive rats
Authors: Jankowski Marek , Wang Donghao , Danalache Bogdan , Gangal Marius , Gutkowska Jolanta
Published: July 2010

An increasing amount of evidence demonstrates the beneficial role of oxytocin (OT) in the cardiovascular system. Similar actions are attributed to genistein, an isoflavonic phytoestrogen. The treatment with genistein activates the OT system in the aorta of ovariectomized (OVX) Sprague-Dawley (SD) rats. The objective of this study was to determine the effects of low doses of genistein on the OT-induced effects in rat hypertension. The hypothesis tested was that treatment of OVX spontaneously hypertensive rats (SHRs) with genistein improves heart structure and heart work through a mechanism involving the specific OT receptor (OTR). OVX SHRs or SD rats were treated with genistein (in μg/g body wt sc, 10 days) in the presence or absence of an OT antagonist (OTA) [d(CH2)5, Tyr(Me)2, Orn8]-vasotocin or a nonspecific estrogen receptor antagonist (ICI-182780). Vehicle-treated OVX rats served as controls. RT-PCR and Western blot analysis demonstrated that left ventricular (LV) OTR, downregulated by ovariectomy, increased in response to genistein. In SHRs or SD rats, this effect was blocked by OTA or ICI-182780 administration. The OTR was mainly localized in microvessels expressing the CD31 marker and colocalized with endothelial nitric oxide synthase. In SHRs, the genistein-stimulated OTR increases were associated with improved fractional shortening, decreased blood pressure (12 mmHg), decreased heart weight-to-body weight ratio, decreased fibrosis, and lowered brain natriuretic peptide in the LV. The prominent finding of the study is the detrimental effect of OTA treatment on the LV of SHRs. OTA treatment of OVX SHRs resulted in a dramatic worsening of ejection fractions and an augmented fibrosis. In conclusion, these results demonstrate that cardiac OTRs are involved in the regulation of cardiac function of OVX SHRs. The decreases of OTRs may contribute to cardiac pathology following menopause.
Consistency of Angular Tuning in the Rat Vibrissa System
Authors: Hemelt Marie E. , Kwegyir-Afful Ernest E. , Bruno Randy M. , Simons Daniel J. , Keller Asaf
Published: July 2010

Each region along the rat mystacial vibrissa pathway contains neurons that respond preferentially to vibrissa deflections in a particular direction, a property called angular tuning. Angular tuning is normally defined using responses to deflections of the principal vibrissa, which evokes the largest response magnitude. However, neurons in most brain regions respond to multiple vibrissae and do not necessarily respond to different vibrissae with the same angular tuning. We tested the consistency of angular tuning across the receptive field in several stations along the vibrissa-to-cortex pathway: primary somatosensory (barrel) cortex, ventroposterior medial nucleus of the thalamus (VPM), second somatosensory cortex, and superior colliculus. We found that when averaged across the population, neurons in all of these regions have low (superior colliculus and second somatosensory cortex) or statistically insignificant (barrel cortex and VPM) angular tuning consistencies across vibrissae. Nevertheless, in each region there are a small number of neurons that display consistent angular tuning for at least some vibrissae. We discuss the relevance of these findings for the transformation of inputs along the vibrissa trigeminal pathway and for the detection of sensory cues by whisking animals.
Cluster-Based Ranging for Accurate Localization in Wireless Sensor Networks
Authors: Sergi Simone , Pancaldi Fabrizio , Vitetta Giorgio M.
Published: July 2010

A novel ranging technique based on received signal strength (RSS) and suitable to indoor scenarios is illustrated. In the proposed technique, multiple power measurements, associated with the signals radiated by a cluster of nodes surrounding a given target, are jointly processed to improve the quality of RSS-based estimation of the distance between the target and an anchor. Specific algorithms for the generation of a cluster and for the acquisition of power measurements are described. Simulation results show that, when used in indoor positioning systems, the proposed ranging technique is substantially more accurate than noncooperative strategies. In addition, it allows to concentrate significant processing tasks in a limited number of fixed anchors, so reducing maintenance costs and making it possible to adopt cheap and simple portable wireless nodes.
A Comparison of Anchor-Item Designs for the Concurrent Calibration of Large Banks of Likert-Type Items
Authors: García-Pérez Miguel A. , Alcalá-Quintana Rocío , García-Cueto Eduardo
Published: July 2010

Current interest in measuring quality of life is generating interest in the construction of computerized adaptive tests (CATs) with Likert-type items. Calibration of an item bank for use in CAT requires collecting responses to a large number of candidate items. However, the number is usually too large to administer to each subject in the calibration sample. The concurrent anchor-item design solves this problem by splitting the items into separate subtests, with some common items across subtests; then administering each subtest to a different sample; and finally running estimation algorithms once on the aggregated data array, from which a substantial number of responses are then missing. Although the use of anchor-item designs is widespread, the consequences of several configuration decisions on the accuracy of parameter estimates have never been studied in the polytomous case. The present study addresses this question by simulation, comparing the outcomes of several alternatives on the configuration of the anchor-item design. The factors defining variants of the anchor-item design are (a) subtest size, (b) balance of common and unique items per subtest, (c) characteristics of the common items, and (d) criteria for the distribution of unique items across subtests. The results of this study indicate that maximizing accuracy in item parameter recovery requires subtests of the largest possible number of items and the smallest possible number of common items; the characteristics of the common items and the criterion for distribution of unique items do not affect accuracy.
Incorporating Transformative Consumer Research Into the Consumer Behavior Course Experience
Authors: Petkus Ed
Published: July 2010

In contrast to understanding consumer behavior for the benefit of business organizations, transformative consumer research (TCR) seeks to understand consumer behavior for the benefit of consumers themselves. Following Mari’s (2008) call for the incorporation of TCR in doctoral programs in marketing, this article outlines the relevance of TCR to the undergraduate consumer behavior course experience and develops topical and structural recommendations for implementation. Empirical evidence indicates positive student perceptions of TCR-based course projects in terms of complementing traditional projects, personal relevance, awareness of social responsibility issues, and marketing applications.
Internal Fire Whirls in a Vertical Shaft
Authors: Chow W.K. , He Z. , Gao Y.
Published: July 2010

Internal fire whirls induced by a pool fire in a vertical shaft of height 15 m with different ventilation conditions are studied experimentally. Ventilation is provided through a rectangular gap at the side wall with varying widths. Gasoline pool fires with diameters up to 0.46 m are set up at the center of the floor. Flame height and burning duration of the pool fire are measured. Average flame height ranged from 1 to 4.5 m when whirling is onsetted in the vertical shaft. Experimental studies indicate that air supply to the upper part of the shaft is a key factor for onsetting internal fire whirls. Oxygen is required to sustain combustion to generate heat for inducing whirling motions. Therefore, flame will not whirl without adequate oxygen supply. In this study, the flaming zone in a vertical shaft is divided into four stages: the initial stage, flame rising-up stage, stable flame, whirling stage and decay stage. Based on the flame height correlations for free burning pool fires, the fuel consumption rate of the pool fire in the shaft at each stage is estimated. Correlations of the whirling flame height with fuel mass and other key parameters are then derived. Computational fluid dynamics is applied to examine the validity of the derived correlation expressions.
Implementing Environmental Management Systems in Small- and Medium-Sized Hotels: Obstacles
Authors: Chan Eric S. W.
Published: July 2010

Small- and medium-sized enterprises (SMEs) make up the vast majority of businesses in Hong Kong. However, a review of the literature about environmental management and environmental management systems (EMSs) reveals that very few studies have examined EMS implementation in small- and medium-sized hotels (SMHs). This study aimed to identify the barriers to the adoption and implementation of a formal EMS by SMHs in Hong Kong. Exploratory factor analysis indicated that nine factors can hinder the adoption of such a system by SMHs, five of which are unique to these hotels. In descending order, they are (a) lack of a sense of urgency, (b) ambiguity of EMS standards, (c) lack of qualified verifiers/consultants, (d) conflicting guidance, and (e) inconsistent support. The findings offer some explanation for the limited action taken by these hotels to improve their environmental performance. The policy implications for hotel managers who are committed to implementing an EMS are also discussed.
Niacin improves small artery vasodilatory function and compliance in statin-treated type 2 diabetic patients
Authors: Hamilton Sandra J , Chew Gerard T , Davis Timothy ME , Watts Gerald F
Published: July 2010

We investigated the effect of niacin (nicotinic acid prolonged release) on forearm vasodilatory function and arterial compliance in statin-treated type 2 diabetic patients with endothelial dysfunction. In a parallel group study, we randomised 15 subjects, with LDL-cholesterol ≤2.5 mmol/L, to niacin (dose titrated to 1500 mg/day over 8 weeks, then maintained for a further 12 weeks) or no additional treatment. Niacin increased maximal post-ischaemic forearm blood flow (mean ± SEM 6.4±2.4 vs. —2.3±1.2 ml/100 ml/min, p = 0.001) and small artery compliance (1.3±0.8 vs. —2.3±1.1 ml/mmHg, p = 0.01) compared with no additional treatment, but did not alter large artery compliance, blood pressure nor heart rate. Niacin decreased serum triglycerides by 47% ( p = 0.04), with no change in LDL-cholesterol, HDL-cholesterol, apolipoprotein (Apo) B-100 nor ApoA-I ( p > 0.05). Adding niacin to statin therapy improves small artery vasodilatory function and compliance in type 2 diabetes. This may relate to a decrease in serum triglycerides and/or a direct benefit of niacin on vascular biology.
The mean does not mean as much anymore: finding sub-groups for tailored therapeutics
Authors: Ruberg Stephen J , Lei Chen  , Yanping Wang
Published: July 2010

Background The genomics revolution is still in its infancy, and there is much to learn about how to transform biological knowledge into useful medicines to further public health. At the bedside, we are asking how and why individual patients respond to different drug treatments in different ways. In addition to genetic mechanisms, there are many clinical markers (e.g. medical history, disease severity) as well as social/environmental factors (e.g. smoking habits) that can be used to identify who may or may not respond to treatment.

Purpose This issue has some considerable statistical complexity, and different approaches to the analysis of clinical trials may yield more interesting insights into the problem. Novel applications of statistical methods will be discussed, and examples will be used to demonstrate sub-group identification.

Methods In order to evaluate many potential predictors of response, we use recursive partitioning methods to identify predictor variables and their cut-off values to define sub-groups of patients with differential treatment response. Validation of this variable/model selection approach was done using independent data from other clinical trials.

Results In one example, a classification tree was developed using baseline measures to define important sub-groups of patients that responded much better than the overall mean response in the study. In a second example, a classification tree was built based on measures of response early in treatment to predict longer-term responders and nonresponders.

Limitation Classification algorithms can be prone to over-fitting, and validation of results is an important consideration. Obviously, analyses are limited by the available predictor variables.

Conclusions Using classification trees proved to be very useful in evaluating large numbers of potential predictors to find sub-groups of patients with exceptional response. The method is easy to use, and clinicians can easily interpret and implement results. This approach can be helpful in tailoring treatments to individual patients. Clinical Trials 2010; 7: 574—583. http://ctj.sagepub.com
Feed the world
Authors: Donaldson Caitlyn
Published: July 2010

In the UK and many other developed countries, it may be easy to forget that hunger, not obesity, is the more urgent concern for most of the world’s population. Yet the economic downturn and high food prices have set back the fight against under-nutrition — Caitlyn Donaldson asks are we doomed to have hungry people on earth forever?
Application of advanced analytical techniques to study structure–property relationship of hot rolled high strength low alloy steel
Authors: Timokhina I. B. , Hodgson P. D. , Ringer S. P. , Zheng R. K. , Pereloma E. V.
Published: July 2010

The microstructure–property relationship in conventional high strength low alloy (HSLA) steel was evaluated using data obtained from transmission electron microscopy (TEM) and atom probe tomography (APT). Atom probe tomography allowed the characterisation of fine TiC particles with average radius of 3±1·2 nm that were not observed by TEM. The increase in the yield strength of steel due to the presence of fine precipitates was calculated to be 128 MPa.
Determination of transition temperatures during freezing and melting of interdendritic phases in Ni based superalloys
Authors: D'Souza N. , Dong H. B.
Published: July 2010

Differential scanning calorimetry (DSC) coupled with microstructural analysis has been used to characterise the freezing and melting response in a typical Ni based superalloy, CMSX10K. Transition temperatures and evolution of fraction solid (or liquid) during freezing and melting are determined from enthalpy considerations. Significant differences in heat capacity ( CP) curves exist between the heating and cooling. It is shown that differences between freezing and melting kinetics occur because of undercooling, which is most significant beyond the solidus temperature up to the onset of eutectic freezing. The correlation of DSC heating and cooling curves to quantitatively characterise directional solidification has been demonstrated.
Compressive properties of closed cell Al alloy–fly ash particle composite foams
Authors: Mu Y. L. , Yao G. C. , Luo H. J.
Published: July 2010

The closed cell aluminium alloy–fly ash particle composite (Al/FA) foams containing 1·5 wt- fly ash were manufactured by molten body transitional foaming process. The quasi-static compressive properties of Al/FA have been investigated. Results show the compressive stress–strain curves of Al/FA foams exhibit three regions, i.e. the elastic region, the plastic plateau region and the densification region. A linear relationship between the densification strain and the relative density was obtained. The relation between the plastic collapse stress and the relative density can be described with Gibson and Ashby's model. The energy absorption capacities of the Al/FA foams gradually increase with increasing strain and relative density.
Endothelium-derived but not platelet-derived protein disulfide isomerase is required for thrombus formation in vivo
Authors: Jasuja Reema , Furie Bruce , Furie Barbara C.
Published: July 2010

Protein disulfide isomerase (PDI) catalyzes the oxidation reduction and isomerization of disulfide bonds. We have previously identified an important role for extracellular PDI during thrombus formation in vivo. Here, we show that endothelial cells are a critical cellular source of secreted PDI, important for fibrin generation and platelet accumulation in vivo. Functional PDI is rapidly secreted from human umbilical vein endothelial cells in culture upon activation with thrombin or after laser-induced stimulation. PDI is localized in different cellular compartments in activated and quiescent endothelial cells, and is redistributed to the plasma membrane after cell activation. In vivo studies using intravital microscopy show that PDI appears rapidly after laser-induced vessel wall injury, before the appearance of the platelet thrombus. If platelet thrombus formation is inhibited by the infusion of eptifibatide into the circulation, PDI is detected after vessel wall injury, and fibrin deposition is normal. Treatment of mice with a function blocking anti-PDI antibody completely inhibits fibrin generation in eptifibatide-treated mice. These results indicate that, although both platelets and endothelial cells secrete PDI after laser-induced injury, PDI from endothelial cells is required for fibrin generation in vivo.
Expression pattern of the thrombopoietin receptor (Mpl) in the murine central nervous system
Authors: Ivanova Anna , Wuerfel Jens , Zhang Juan , Hoffmann Olaf , Ballmaier Matthias , Dame Christof
Published: July 2010

Background

Thrombopoietin (Thpo) and its receptor (Mpl), which regulate megakaryopoiesis, are expressed in the central nervous system (CNS), where Thpo is thought to exert pro-apoptotic effects on newly generated neurons. Mpl expression has been analysed in brain tissue on transcript level and in cultured primary rat neurons and astrocytes on protein level. Herein, we analysed Mpl expression in the developing and adult murine CNS by immunohistochemistry and investigated the brain of mice with homozygous Mpl deficiency (Mpl
-/-) by MRI.

Results

Mpl was not detectable at developmental stages E12 to E15 in any resident cells of the CNS. From E18 onwards, robust Mpl expression was found in various brain areas, including cerebral cortex, olfactory bulb, thalamus, hypothalamus, medulla, pons, and the grey matter of spinal cord. However, major developmental changes became obvious: In the subventricular zone of the cerebral cortex Mpl expression occurred only during late gestation, while in the hippocampus Mpl expression was detectable for first time at stage P4. In the white matter of the cerebellum Mpl expression was restricted to the perinatal period. In the adult cerebellum, Mpl expression switched to Purkinje cell. The majority of other Mpl-positive cells were NeuN-positive neurons. None of the cells could be double-labelled with astrocyte marker GFAP. Mpl
-/- mice showed no gross abnormalities of the brain.

Conclusions

Our data locate Mpl expression to neurons at different subdivisions of the spinal cord, rhombencephalon, midbrain and prosencephalon. Besides neuronal cells Mpl protein is also expressed in Purkinje cells of the adult cerebellum.
The extracellular matrix microtopography drives critical changes in cellular motility and Rho A activity in colon cancer cells
Authors: Rapier Rebecca , Huq Jameela , Vishnubhotla Ramana , Bulic Marinka , Perrault Cecile M , Metlushko Vitali , Cho Michael , Tay Roger Tran Son , Glover Sarah C
Published: July 2010

We have shown that the microtopography (mT) underlying colon cancer changes as a tumor de-differentiates. We distinguish the well-differentiated mT based on the increasing number of "pits" and poorly differentiated mT on the basis of increasing number of "posts." We investigated Rho A as a mechanosensing protein using mT features derived from those observed in the ECM of colon cancer. We evaluated Rho A activity in less-tumorogenic (Caco-2 E) and more tumorigenic (SW620) colon cancer cell-lines on microfabricated pits and posts at 2.5 μm diameter and 200 nm depth/height. In Caco-2 E cells, we observed a decrease in Rho A activity as well as in the ratio of G/F actin on surfaces with either pits or posts but despite this low activity, knockdown of Rho A led to a significant decrease in confined motility suggesting that while Rho A activity is reduced on these surfaces it still plays an important role in controlling cellular response to barriers. In SW620 cells, we observed that Rho A activity was greatest in cells plated on a post microtopography which led to increased cell motility, and an increase in actin cytoskeletal turnover.
Cerebral microcirculation is impaired during sepsis: an experimental study
Authors: Taccone Fabio Silvio , Su Fuhong , Pierrakos Charalampos , He Xinrong , James Syril , Dewitte Olivier , Vincent Jean-Louis , De Backer Daniel
Published: July 2010

Introduction

Pathophysiology of brain dysfunction due to sepsis remains poorly understood. Cerebral microcirculatory alterations may play a role; however, experimental data are scarce. This study sought to investigate whether the cerebral microcirculation is altered in a clinically relevant animal model of septic shock.

Methods

Fifteen anesthetized, invasively monitored, and mechanically ventilated female sheep were allocated to a sham procedure (n = 5) or sepsis (n = 10), in which peritonitis was induced by intra-abdominal injection of autologous faeces. Animals were observed until spontaneous death or for a maximum of 20 hours. In addition to global hemodynamic assessment, the microcirculation of the cerebral cortex was evaluated using Sidestream Dark-Field (SDF) videomicroscopy at baseline, 6 hours, 12 hours and at shock onset. At least five images of 20 seconds each from separate areas were recorded at each time point and stored under a random number to be analyzed, using a semi-quantitative method, by an investigator blinded to time and condition.

Results

All septic animals developed a hyperdynamic state associated with organ dysfunction and, ultimately, septic shock. In the septic animals, there was a progressive decrease in cerebral total perfused vessel density (from 5.9 ± 0.9 at baseline to 4.8 ± 0.7 n/mm at shock onset, P = 0.009), functional capillary density (from 2.8 ± 0.4 to 2.1 ± 0.7 n/mm, P = 0.049), the proportion of small perfused vessels (from 95 ± 3 to 85 ± 8%, P = 0.02), and the total number of perfused capillaries (from 22.7 ± 2.7 to 17.5 ± 5.2 n/mm, P = 0.04). There were no significant changes in microcirculatory flow index over time. In sham animals, the cerebral microcirculation was unaltered during the study period.

Conclusions

In this model of peritonitis, the cerebral microcirculation was impaired during sepsis, with a significant reduction in perfused small vessels at the onset of septic shock. These alterations may play a role in the pathogenesis of septic encephalopathy.
Bedside quantification of dead-space fraction using routine clinical data in patients with acute lung injury: secondary analysis of two prospective trials
Authors: Siddiki Hassan , Kojicic Marija , Li Guangxi , Yilmaz Murat , Thompson Taylor B , Hubmayr Rolf D , Gajic Ognjen
Published: July 2010

Introduction

Dead-space fraction (Vd/Vt) has been shown to be a powerful predictor of mortality in acute lung injury (ALI) patients. The measurement of Vd/Vt is based on the analysis of expired CO2 which is not a part of standard practice thus limiting widespread clinical application of this method. The objective of this study was to determine prognostic value of Vd/Vt estimated from routinely collected pulmonary variables.

Methods

Secondary analysis of the original data from two prospective studies of ALI patients. Estimated Vd/Vt was calculated using the rearranged alveolar gas equation:

Vd
/
Vt
=
1
−
[
(
0.
86
×

V
˙

CO

2est

)
/

(

VE
×

PaCO

2

)

]

where

V
˙

CO

2
est

is the estimated CO2 production calculated from the Harris Benedict equation, minute ventilation (VE) is obtained from the ventilator rate and expired tidal volume and PaCO2 from arterial gas analysis. Logistic regression models were created to determine the prognostic value of estimated Vd/Vt.

Results

One hundred and nine patients in Mayo Clinic validation cohort and 1896 patients in ARDS-net cohort demonstrated an increase in percent mortality for every 10% increase in Vd/Vt in a dose response fashion. After adjustment for non-pulmonary and pulmonary prognostic variables, both day 1 (adjusted odds ratio-OR = 1.07, 95%CI 1.03 to 1.13) and day 3 (OR = 1.12, 95% CI 1.06 to 1.18) estimated dead-space fraction predicted hospital mortality.

Conclusions

Elevated estimated Vd/Vt predicts mortality in ALI patients in a dose response manner. A modified alveolar gas equation may be of clinical value for a rapid bedside estimation of Vd/Vt, utilizing routinely collected clinical data.
A Proposed Rapid Visual Screening Procedure for Seismic Evaluation of RC-Frame Buildings in India
Authors: Jain Sudhir K. , Mitra Keya , Kumar Manish , Shah Mehul
Published: July 2010

Poor performance of reinforced concrete (RC) frame buildings in India during past earthquakes has been a matter of serious concern. Hence, it becomes important to identify and strengthen the deficient buildings. When dealing with a large building stock, one needs evaluation methods for quick assessment of the seismic safety of existing buildings so that corrective retrofitting measures may be undertaken on the deficient buildings. This paper presents a review of some of the available methods for rapid visual screening (RVS) of RC-frame buildings and proposes a RVS method for RC-frame buildings in India based on systematic studies on damage data of the 2001 Bhuj earthquake.
Site-Response Characteristics Evaluated from Strong Motion Records of the 2003 Boumerdes, Algeria, Earthquake
Authors: Meslem Abdelghani , Yamazaki Fumio , Maruyama Yoshihisa , Benouar Djillali , Laouami Nasser , Benkaci Nassima
Published: July 2010

Site response characteristics at seismic stations were investigated using horizontal-to-vertical (H/V) spectral ratios calculated from a seismic-motion dataset of the 2003 Boumerdes earthquake, and transfer functions were evaluated from soil profile data. Although high peak ground acceleration (PGA) values were recorded at some sites, the nonlinear effect at these stations was not clear. The H/V spectral ratios calculated from weak and strong motion events did not show a clear difference in the predominant period and amplitudes, and the shapes of the H/V ratios were flat for some stations. These observations are characteristic of the presence of firm to hard layers under the stations; however, one station was located on Quaternary deposits showed a remarkable amplification at the predominant period and a high PGA value.
Evidence of Oxidative Stress in Alzheimer's Disease Brain and Antioxidant Therapy
Authors: Praticò Domenico
Published: July 2010

Alzheimer's disease (AD) is the most common form of neurodegenerative disease associated with dementia in the elderly. Although the initiating events are still unknown, it is clear that AD, at least in its sporadic form, results from the combination of genetic risk factors with different epigenetic events. Among them, a growing body of evidence suggests that an imbalance between free radical formation and destruction is involved in AD pathogenesis. This concept originally derived from the free radical hypothesis of aging, which states that the age‐related accumulation of free radicals results in damaged cell components. The fact that age is a key risk factor in AD provides support for this hypothesis. There is a long list of surrogate markers, which includes lipid, DNA, and protein oxidation, of oxidant stress‐mediated injury that have been reported as elevated in the AD brain. Moreover, epidemiologic studies show that dietary intake of natural or synthetic products with a putative antioxidant effect, such as (but not only) vitamin E, reduces the risk of AD. On the other hand, antioxidative intervention studies in animal models of AD‐like amyloidosis show a significant reduction in amyloid β deposition and behavioral improvements. However, a randomized clinical trial of vitamin E supplementation in AD patients shows only a marginal positive effect. Another study reports no effect of vitamin E on the rate of progression of AD in subjects with mild cognitive impairment. This article will review both promises and caveats of the available data and propose future directions to be taken for addressing them.
Chronic Corticosterone Exposure Increases Expression and Decreases Deoxyribonucleic Acid Methylation of Fkbp5 in Mice
Authors: Lee Richard S. , Tamashiro Kellie L. K. , Yang Xiaoju , Purcell Ryan H. , Harvey Amelia , Willour Virginia L. , Huo Yuqing , Rongione Michael , Wand Gary S. , Potash James B.
Published: July 2010

There is evidence for hypercortisolemia playing a role in the generation of psychiatric symptoms and for epigenetic variation within hypothalamic-pituitary-adrenal (HPA) axis genes mediating behavioral changes. We tested the hypothesis that expression changes would be induced in Fkbp5 and other HPA axis genes by chronic exposure to corticosterone and that these changes would occur through the epigenetic mechanism of loss or gain of DNA methylation (DNAm). We administered corticosterone (CORT) to C57BL/6J mice via their drinking water for 4 wk and tested for behavioral and physiological changes and changes in gene expression levels using RNA extracted from hippocampus, hypothalamus, and blood for the following HPA genes: Fkbp5, Nr3c1, Hsp90, Crh, and Crhr1. The CORT mice exhibited anxiety-like behavior in the elevated plus maze test. Chronic exposure to CORT also caused a significant decrease in the hippocampal and blood mRNA levels of Nr3c1 and a decrease in Hsp90 in blood and caused an increase in Fkbp5 for all tissues. Differences were seen in Fkbp5 methylation in hippocampus and hypothalamus. To isolate a single-cell type, we followed up with an HT-22 mouse hippocampal neuronal cell line exposed to CORT. After 7 d, we observed a 2.4-fold increase in Fkbp5 expression and a decrease in DNAm. In the CORT-treated mice, we also observed changes in blood DNAm in Fkbp5. Our results suggest DNAm plays a role in mediating effects of glucocorticoid exposure on Fkbp5 function, with potential consequences for behavior.
Serotonin 2B receptor signaling is required for craniofacial morphogenesis and jaw joint formation in Xenopus
Authors: Reisoli Elisa , De Lucchini Stefania , Nardi Irma , Ori Michela
Published: July 2010

Serotonin (5-HT) is a neuromodulator that plays many different roles in adult and embryonic life. Among the 5-HT receptors, 5-HT2B is one of the key mediators of 5-HT functions during development. We used Xenopus laevis as a model system to further investigate the role of 5-HT2B in embryogenesis, focusing on craniofacial development. By means of gene gain- and loss-of-function approaches and tissue transplantation assays, we demonstrated that 5-HT2B modulates, in a cell-autonomous manner, postmigratory skeletogenic cranial neural crest cell (NCC) behavior without altering early steps of cranial NCC development and migration. 5-HT2B overexpression induced the formation of an ectopic visceral skeletal element and altered the dorsoventral patterning of the branchial arches. Loss-of-function experiments revealed that 5-HT2B signaling is necessary for jaw joint formation and for shaping the mandibular arch skeletal elements. In particular, 5-HT2B signaling is required to define and sustain the Xbap expression necessary for jaw joint formation. To shed light on the molecular identity of the transduction pathway acting downstream of 5-HT2B, we analyzed the function of phospholipase C beta 3 (PLC) in Xenopus development and showed that PLC is the effector of 5-HT2B during craniofacial development. Our results unveiled an unsuspected role of 5-HT2B in craniofacial development and contribute to our understanding of the interactive network of patterning signals that is involved in the development and evolution of the vertebrate mandibular arch.
Developmental RNA processing of 3′UTRs in Hox mRNAs as a context-dependent mechanism modulating visibility to microRNAs
Authors: Thomsen Stefan , Azzam Ghows , Kaschula Richard , Williams Lucy S. , Alonso Claudio R.
Published: July 2010

The Drosophila Hox gene Ultrabithorax (Ubx) controls the development of thoracic and abdominal segments, allocating segment-specific features to different cell lineages. Recent studies have shown that Ubx expression is post-transcriptionally regulated by two microRNAs (miRNAs), miR-iab4 and miR-iab8, acting on target sites located in the 3′ untranslated regions (UTRs) of Ubx mRNAs. Here, we show that during embryonic development Ubx produces mRNAs with variable 3′UTRs in different regions of the embryo. Analysis of the resulting remodelled 3′UTRs shows that each species harbours different sets of miRNA target sites, converting each class of Ubx mRNA into a considerably different substrate for miRNA regulation. Furthermore, we show that the distinct developmental distributions of Ubx 3′UTRs are established by a mechanism that is independent of miRNA regulation and therefore are not the consequence of miR-iab4/8-mediated RNA degradation acting on those sensitive mRNA species; instead, we propose that this is a hard-wired 3′UTR processing system that is able to regulate target mRNA visibility to miRNAs according to developmental context. We show that reporter constructs that include Ubx short and long 3′UTR sequences display differential expression within the embryonic central nervous system, and also demonstrate that mRNAs of three other Hox genes suffer similar and synchronous developmental 3′UTR processing events during embryogenesis. Our work thus reveals that developmental RNA processing of 3′UTR sequences is a general molecular strategy used by a key family of developmental regulators so that their transcripts can display different levels of visibility to miRNA regulation according to developmental cues.
Local Discouragement and Global Collapse: A Theory of Coordination Avalanches
Authors: Jeitschko Thomas D , Taylor Curtis R
Published: July 2010

We study a dynamic game in which all players initially possess the same information and coordinate on a high level of activity. Eventually, players with a long string of bad experiences become inactive. This prospect can cause a coordination avalanche in which all activity in the population stops. Coordination avalanches are part of Pareto-efficient equilibria; they can occur at any point in the game; their occurrence does not depend on the true state of nature; and allowing players to exchange information may merely hasten their onset. We present applications to search markets, organizational meltdown, and inefficient computer upgrades. (JEL D83)
Costly Predation and the Distribution of Competence
Authors: Conlisk John
Published: July 2010

An evolutionary game model shows how an equilibrium distribution of competence may evolve when members of a population prey on one another, but when predatory competence is costly to acquire. Under one interpretation, the competence distribution is an endogenously determined distribution of bounded rationality. An example shows how “tricksters” and “suckers” might coexist in the long run. The analysis leads to a curious result about a mixed equilibrium for a symmetric, zero-sum game. An increase in the costs of one or more competence levels has exactly zero effect on the fraction of the population at those levels. (JEL C79, D89)
Characteristics and discrimination of five types of wood-plastic composites by FTIR spectroscopy combined with principal component analysis
Authors: Lee Chia-Huang , Wu Tung-Lin , Chen Yong-Long , Wu Jyh-Horng
Published: July 2010

The analytical potential of attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy has been tested on the following wood-plastic composites (WPCs): high and low density polyethylene (HDPE and LDPE), polypropylene (PP), polystyrene (PS), and a recycled plastic (rHDPE). The data set of ATR-FTIR spectra has been analyzed by principal component analysis (PCA) and the studied samples could be grouped according to their polymeric matrixes. Additionally, ATR-FTIR spectroscopy proved to be a useful tool for determining the distribution profile of wood and plastic materials within different types of WPCs. Accordingly, the plastic content of the surface layers of HDPE, rHDPE, and PP composites was significantly higher than that of the core layer, whereas homogenous dispersion was observed in the LDPE composite. Among all WPCs, the PS composite displayed the worst dispersion.
Tolerância diferencial de variedades de cana-de-açúcar a estresse por herbicidas
Authors: Ferreira Renato Rodrigues , Oliveira Fabrício Tadeu Rodrigues de , Delite Fabrício de Souza , Azevedo Ricardo Antunes , Nicolai Marcelo , Carvalho Saul Jorge Pinto de , Christoffoleti Pedro Jacob , Figueira Antonio Vargas De Oliveira
Published: July 2010

Este trabalho foi desenvolvido com o objetivo de realizar triagem primária para caracterização da tolerância de variedades SP e CTC de cana-de-açúcar à aplicação de dez herbicidas comumente recomendados para manejo de plantas daninhas nesta cultura. Dois experimentos foram desenvolvidos com esquema fatorial entre variedades de cana-de-açúcar e onze tratamentos herbicidas. No primeiro experimento utilizaram-se sete variedades SP (fatorial 7 x 11): SP80-1842, SP80-3280, SP83-2847, SP87-344, SP87-396, SP89-1115 e SP90-3414. No segundo experimento, foram avaliadas seis variedades CTC (fatorial 6 x 11): CTC1, CTC2, CTC3, CTC4, CTC5 e CTC6. Os tratamentos herbicidas aplicados em pós-emergência inicial foram: ametryn, ametryn + trifloxysulfuron-sodium, clomazone, diuron + hexazinone, isoxaflutole, imazapic, 2,4-D, tebuthiuron, sulfentrazone, MSMA e testemunha sem aplicação. Avaliou-se massa fresca, altura, teor de clorofila (índice SPAD) e perfilhamento, todos em termos percentuais relativos à testemunha sem aplicação. Constatou-se tolerância diferencial das variedades de cana-de-açúcar aos herbicidas comumente utilizados na cultura. As variedades SP80-3280 e CTC2 foram as mais tolerantes aos tratamentos herbicidas, podendo ter esta característica explorada em programas de melhoramento genético.
Variação do teor de carboidratos em genótipos de batata armazenados em diferentes temperaturas
Authors: Bervald Clauber Mateus Priebe , Bacarin Marcos Antonio , Deuner Sidnei , Trevizol Fabio Cristiano
Published: July 2010

Um problema de armazenar tubérculos de batata em baixa temperatura é o acúmulo de açúcares redutores. Este acúmulo provoca perda do valor comercial dos tubérculos quando processados na forma de "chips". O objetivo do presente trabalho foi verificar a possível alteração nos teores de carboidratos em tubérculos de diferentes genótipos de batata antes do armazenamento e após o armazenamento a 4 ºC e 20 ºC. Os genótipos produzidos na Embrapa Clima Temperado, em Pelotas (RS), foram avaliados quanto aos teores de amido, sacarose, açúcares solúveis totais e açúcares redutores. O tratamento controle consistiu da análise dos tubérculos logo após a colheita, enquanto os demais foram divididos em dois lotes, padronizados quanto ao tamanho e armazenados a 4 ºC e 20 ºC durante 33 dias, sendo então novamente avaliados pelas mesmas análises descritas anteriormente. Os teores de amido foram pouco alterados pelas condições de armazenamento. Os teores de açúcares solúveis totais e açúcares redutores aumentaram quando os tubérculos foram submetidos à refrigeração, porém com taxas de incremento diferentes entre os genótipos. Para os teores de sacarose, de maneira geral, houve redução com o armazenamento em ambas as condições. A cultivar Pérola e os clones C-1740-11-94 e C-1786-6-94 tiveram o menor acúmulo de açúcares solúveis quando armazenados a baixa temperatura.
Descrição de ovos e ninfas de Triatoma klugi (Hemiptera, Reduviidae, Triatominae)
Authors: Jurberg José , Barbosa Helene S. , Galvão Cleber , Rocha Dayse da S. , Silva Maria Beatriz A.
Published: July 2010

Os autores descreveram as características morfológicas de Triatoma klugi Carcavallo, Jurberg, Lent & Galvão, 2001 pertencente ao grupo de espécies que compõem o "complexo T. oliveirai". Até o presente tem sido difícil separar essas espécies com base nas características ninfais, o que justifica o desenvolvimento deste trabalho. Os espécimes foram coletados em frestas de rochas no morro Malavok na localidade de Linha Brasil, município de Nova Petrópolis, no Estado do Rio Grande do Sul. O local de captura dos triatomíneos situa-se entre 700 e 800 m de altitude (29º18'38''S, 51º04'57''W). Juntamente com T. oliveirai (Neiva, Pinto & Lent, 1939), espécie morfologicamente mais próxima, são as únicas do complexo que não foram encontradas, até o momento, no Estado do Mato Grosso, Mato Grosso do Sul e Goiás, Brasil. Em condições experimentais, já foi testada e comprovada a sua susceptibilidade à infecção pelo Trypanosoma cruzi (Chagas, 1909) e Trypanosoma rangeli (Tejera, 1920). A análise comparativa das ornamentações do exocório dos ovos e de três estádios ninfais de T. klugi por microscopia óptica e microscopia eletrônica de varredura mostrou algumas particularidades morfológicas, com destaque para: a face ventral da cabeça, o sulco estridulatório e os últimos segmentos abdominais (IX, X - futura genitália e XI - tubo anal). Esses dados contribuem para a ampliação dos parâmetros diferenciais visando à diagnose de T. klugi durante o seu desenvolvimento ninfal.
Duas espécies novas de Lophoblatta (Blattellidae, Pseudophyllodromiinae) coletadas na Mata Atlântica, Rio de Janeiro
Authors: Lopes Sonia Maria , Oliveira Edivar H. de
Published: July 2010

São descritas Lophoblatta leuropeltiana sp. nov. e L. tijucana sp. nov. do Rio de Janeiro, com ilustrações da genitália dos machos e da fêmea.
Cardiomiectomia com fundoplicatura parcial videolaparoscópica no tratamento do megaesôfago não avançado: estudo de 50 casos
Authors: Domene Carlos Eduardo , Santo Marco Aurélio , Onari Pedro , Volpe Paula , Pinotti Henrique Walter
Published: July 2010

Foram estudados prospectivamente cinqüenta pacientes com megaesôfago não avançado tratados por cardiomiectomia com fundoplicatura parcial por via laparoscópica, avaliados sob o ponto de vista clínico e funcional. Houve 12% de complicações intra-operatórias, duas complicações pós-operatórias imediatas e um óbito. Não houve conversões ou complicações tardias. Os resultados ótimos e bons somaram 97,9% dos casos. Houve tendência à diminuição radiológica do calibre do esôfago e desaparecimento da esofagite à endoscopia. A eletromanometria mostrou diminuição significativa da pressão média do esfíncter inferior do esôfago após a operação; a pHmetria de 24 horas constatou diminuição da estase esofágica e ausência de refluxo gastro-esofágico no pós-operatório. Não houve diferença entre os resultados do tratamento de pacientes com megaesôfago chagásico e não chagásico. Os pacientes tiveram o benefício da cirurgia laparoscópica de menor dor, rápida realimentação, alta precoce e breve retorno às atividades habituais.
Metaphysics in Königsberg prior to Kant (1703-1770)
Authors: Sgarbi Marco
Published: July 2010

The present contribute aims to reconstruct, using the methodology of intellectual history, the broad spectrum of metaphysical doctrines that Kant could know during the years of the formation of his philosophy. The first part deals with the teaching of metaphysics in Königsberg from 1703 to 1770. The second part examines the main characteristics of the metaphysics in the various handbooks, which were taught at the Albertina, in order to have an exhaustive overview of all metaphysical positions.
La libertad civil como condición de posibilidad de la autonomía moral: sobre la aportación de Freud al planteamiento práctico de Kant
Authors: Zahonero Luis Alegre
Published: July 2010

Es frecuente buscar en Freud a un crítico de la Ilustración y, en particular, del modo de pensar la moral heredero del planteamiento kantiano. Sin embargo, Freud se limita a descubrir en la naturaleza humana un importante obstáculo del que el proyecto ilustrado no se podrá ya desentender. Este obstáculo, que afecta de un modo decisivo al modo como entender el paso a la mayoría de edad, remite a la existencia de un determinado reino de la heteronomía cuyo rasgo más característico es su capacidad para suplantar la voz de la autonomía moral: al igual que la ley moral en Kant, el superyó -una vez ha interiorizado en la infancia y asumido como propios determinados contenidos de cultura (independientemente de su racionalidad y de su posible validez como leyes universales)- también ordena poderosamente sin prometer nada (externo) ni amenazar con nada (externo). En estas condiciones, el proyecto de investir a la razón como autoridad suprema (proyecto que Freud y Kant comparten) depende de la existencia de una organización republicana que garantice un programa pedagógico para el que "mayoría de edad" no signifique llamar "yo" a la cristalización interior de las costumbres de los ancestros sino a la capacidad efectiva de guiarse por la propia razón (lo cual, tras el descubrimiento de los mecanismos elementales del psiquismo, se convierte en un imperativo no sólo moral sino también terapéutico).
Bulgakov's sophiology as philosopheme: non-ontology and ontogenesis
Authors: Hryschko Myroslav Feodosijeviè
Published: July 2010

The text examines Sergej Nikolajeviè Bulgakov's description of the philosopheme as thoroughly "immanent" (viz., the immanence of man qua being, such that ontology in Bulgakov becomes a conceptual analogue for immanence) and the corollary that such immanence necessarily excludes the problematic of the "creation of the world." Because of this resolute immanence and the notion that the creation of the world in the form of creatio ex nihilo requires a non-immanent or non-ontological thought and concept, the problematic for Bulgakov is approached only by a theologeme. Appropriating this argument as material for a cursory philosopheme, the text attempts to transform Bulgakov's theologeme into a philosopheme through an elision of God and dogma that overdetermines the theologeme. This philosopheme (nascent within Bulgakov's work itself, in both his hesitation to the overdetermination of immanence and the commitment to the problem of creation) would be a thoroughly non-ontological philosopheme, one that allows for the treatment of the problematic of "creation" or singular ontogenesis, yet with the corollary that this philosopheme must rely on an "ontological zero" Such a philosopheme qua ontologically empty formula nevertheless remains ontologically significant insofar as it is to evince the limit of ontology, in the ontological zero's non-relationality to ontology.
Tratamento colonoscópico de fístula colo-cutânea com plugue de colágeno
Authors: Coelho Júlio Cezar Uili , Gomes Guilherme Francisco , Macedo Júlio Japiassu Marinho de
Published: July 2010

INTRODUÇÃO: Fístulas digestivas permanecem como complicações mais frequentes após operações abdominais. Quando ocorrem, o tempo de internação, custo e a morbimortalidade pós-operatória aumentam. Apesar das várias opções de tratamento, um número significativo de pacientes requerem procedimentos cirúrgicos complexos para fechá-las. O desenvolvimento da endoscopia intervencionista proporcionou nova opção de tratamento para fístulas gastro-intestinais. RELATO DO CASO: Paciente com fístula colocutânea foi tratada com sucesso com um plugue de colágeno. A injeção percutânea de azul de metileno identificou o orifício interno da fístula no cólon transverso. Aplicação de clips anteriormente realizada não foi bem sucedida. A fístula fechou em poucos dias após a introdução de plugue de colágeno através de um procedimento combinado percutâneo-colonoscopico. CONCLUSÃO: O uso de tampões de colágeno por procedimento percutâneo e endoscópico combinado tem a vantagem de permitir a redução do tempo de tratamento da fístula intestinal e pode evitar intervenções cirúrgicas mais complexas.