Hydrogels were highly flexible and relatively strong at 37 degrees C, with tensile strengths from 0.3 to 1.1 MPa and elongations at break from 344 to 1841% depending on NIPAAm/HEMAPLA ratio, AAc content, and polylactide length. Increasing the collagen content decreased both buy AS1842856 elongation at break and tensile strength. Hydrogel weight loss at 37 degrees C was 85-96% over 21 days and varied with polylactide content. Hydrogel weight loss at 37 degrees C was 85-96% over 21 days and varied with polylactide content. Degradation products were

shown to be noncytotoxic. Cell adhesion on the hydrogels was 30% of that for tissue culture polystyrene but increased to statistically approximate this control surface after collagen incorporation. These newly described thermoresponsive copolymers demonstrated attractive properties to serve as cell or pharmaceutical delivery vehicles for a variety of tissue engineering applications.”
“Epileptic seizures increase the birth of new neurons in the adult hippocampus. Although the consequences of aberrant neurogenesis on behavior are not fully understood, one hypothesis is that seizure-generated neurons might form faulty circuits that disrupt hippocampal functions, such as learning and memory. In the present study, we employed long-term amygdala kindling (i.e., rats receive 99-electrical stimulations)

to examine the effect of repeated selleck chemical seizures on hippocampal neurogenesis and behavior. We labeled seizure-generated cells with the proliferation marker BrdU after 30-stimulations and continued kindling for an additional 4 weeks to allow newborn neurons to mature under conditions of repeated seizures. After kindling was complete, rats were tested in a trace fear conditioning task and sacrificed 2 h later to examine if 4-week old

newborn cells were recruited into circuits involved in the retrieval of emotional memory. Compared to non-kindled controls, long-term kindled rats showed significant impairments in fear memory reflected in a decrease in conditioned freezing to both tone and contextual Bafilomycin A1 mw cues during testing. Moreover, long-term kindling also prevented the activation of 4-week old newborn cells in response to fear memory retrieval. These results indicate that the presence of seizure activity during cell maturation impedes the ability of new neurons to integrate properly into circuits important in memory formation. Together, our findings suggest that aberrant seizure-induced neurogenesis might contribute to the development of learning impairments in chronic epilepsy and raise the possibility that targeting the reduced activation of adult born neurons could represent a beneficial strategy to reverse cognitive deficits in some epileptic patients. (C) 2012 Elsevier Inc. All rights reserved.

In addition, nodules formed by R. etli rpoH1 and rpoH2 rpoH1 mutants showed premature senescence. It was also determined that fixNf and fixKf expression was affected in rpoH1 mutants. Both rpoH genes were induced under microaerobic conditions and in the stationary growth phase, but not in response to heat shock. Analysis of the upstream region of rpoH1 revealed a sigma(70) and a probable sigma(E) promoter, whereas in rpoH2, one probable sigma(E)-dependent promoter was detected. In conclusion, the two RpoH proteins operate under different stress conditions,

RpoH1 in heat-shock and oxidative responses, and RpoH2 in osmotic tolerance.”
“This DZNeP datasheet paper is concerned with optimal harvesting policy for predator-prey system of three species with age-dependent. The existence and uniqueness of non-negative solution of the system are proved using the fixed

pint theorem. The existence of optimal control strategy is discussed, optimality conditions are derived by means of normal cone and Dubovitskii-Milyutin’s general theory. Our results extend some known criteria.”
“Our objective was to examine the association of attention deficit and disorganization in boys with and without specific developmental disorder of motor function. Four groups of boys between the age of 7 and 12 years(1) Disorganization + coordination disorder (n = 30); (2) Coordination disorder (n = 33); (3) Disorganization (n = 28); and (4) Control (n = 29)were included. Teachers completed the Questionnaire for Assessing the Students’ Organizational Abilities for the Teacher and the Conners’ Teachers Rating MAPK inhibitor Scale-Revised. The Movement Assessment

Battery for Children and 2 subscales of an intelligence test (vocabulary and similarities) were administered. A significantly increased rate of attention deficit in children with organizational deficit was identified. Attention deficit in children with specific motor disorder was exclusively associated with an organizational deficit. Organizational deficit in childhood is highly associated with attention deficit, and this association is particularly relevant in children with specific coordination see more disorder.”
“Hsp70 molecular chaperones are implicated in a wide variety of cellular processes, including protein biogenesis, protection of the proteome from stress, recovery of proteins from aggregates, facilitation of protein translocation across membranes, and more specialized roles such as disassembly of particular protein complexes. It is a fascinating question to ask how the mechanism of these deceptively simple molecular machines is matched to their roles in these wide-ranging processes. The key is a combination of the nature of the recognition and binding of Hsp70 substrates and the impact of Hsp70 action on their substrates. In many cases, the binding, which relies on interaction with an extended, accessible short hydrophobic sequence, favors more unfolded states of client proteins.

“
“Background. Coronary artery bypass surgery employing minimal extracorporeal circulation (MECC) was compared with standard extracorporeal circulation (ECC) and off-pump coronary artery bypass graft surgery (OPCABG) with regard to the perioperative course.\n\nMethods. From January 2004 to December 2007, 1,674 patients (n = 558 MECC, n = 558 ECC, n = 558 OPCABG) who underwent coronary bypass surgery were studied. The primary end point was in-hospital mortality; secondary end points were perioperative variables, intensive care, and in-hospital course.\n\nResults. Demographic data, comorbidity,

and the European System for Cardiac Operative Risk Evaluation score (MECC 3.0%, ECC 3.5%, OPCABG 3.2%) were similar among the groups, but in-hospital mortality

for elective and urgent/emergent patients was lower in the MECC and OPCABG groups (MECC 3.2%, OPCABG 3.7%, ECC 6.9%; p < 0.05). The number of distal anastomoses was lowest in the OPCABG group, but comparable selleck inhibitor for MECC and ECC patients. Postoperative ventilation time, release of creatinine kinase, catecholamine therapy, drainage loss, and transfusion requirements were lower in the MECC and OPCABG groups, whereas stay in the intensive care unit was shorter only in the latter (p < 0.05).\n\nConclusions. Minimal extracorporeal circulation is an easy and safe procedure for coronary artery bypass graft surgery. In selected patients, the advantages of MECC equal those of OPCABG. MECC should be considered as an alternative to OPCABG GSK2879552 mw and standard ECC procedures.”
“Proteins with internal repeats (Pir) belong to a minor group of covalently linked yeast cell wall proteins. They are not essential for viability

but important for cell wall strength, reduced permeability against plant antifungal enzymes and maintenance of osmotic stability. Here we show the importance of Pir proteins of Saccharomyces cerevisiae for growth at low pH and in presence of various inhibitors. Cell wall analysis of Delta pir1,2,3,4 SU5402 Protein Tyrosine Kinase inhibitor deletion strain revealed slightly increased chitin content and changes in relative proportion of alkali-soluble and insoluble glucan and chitin fractions. Activation of the cell wall integrity pathway was indicated by increased levels of double phosphorylated Mpk1p/Slt2p in the pir deletants.”
“Background: The use of subject-specific finite element (FE) models in clinical practice requires a high level of automation and validation. In Yosibash et al. [2007a. Reliable simulations of the human proximal femur by high-order finite element analysis validated by experimental observations. J. Biomechanics 40, 3688-3699] a novel method for generating high-order finite element (p-FE) models from CT scans was presented and validated by experimental observations on two fresh frozen femurs (harvested from a 30 year old male and 21 year old female). Herein, we substantiate the validation process by enlarging the experimental database (54 year old female femur).

The mechanism of cell adhesion to keratin biomaterials, however, is poorly understood. Therefore, the goal of this work was to investigate the mechanisms by which human hair keratin-based biomaterials facilitate cellular adhesion. Milciclib ic50 Hepatocytes were used as a model cell type due to the abundance of published data on cell adhesion mechanisms and their relatively copious attachment to keratin substrates. The roles of beta(1)- and beta(2)-integrins and the hepatic asialoglycoprotein receptor (ASGPR) in hepatocyte adhesion to keratin substrates

were studied using attachment assays with and without function blocking antibodies. Blocking of the hepatic integrin subunits did not decrease hepatocyte attachment to keratin. Furthermore, adhesion to keratin did not result in the formation of focal

complexes or focal adhesions, nor did it produce an upregulation of phosphorylated-focal adhesion kinase. However, inhibition of hepatic ASGPR decreased the ability of hepatocytes to attach to keratin substrates, which is indicative of the role of this glycoprotein receptor in hepatocyte binding to keratin biomaterials. (C) 2011 Elsevier Ltd. All rights reserved.”
“In flies, the zinc-finger protein Teashirt promotes trunk segmental identities, in part, by repressing the expression and function of anterior hox paralog group (PG) 1-4 genes that specify head fates. Anterior-posterior patterning of the vertebrate hindbrain also requires Hox PG 1-4 function, but the role of vertebrate Ulixertinib teashirt-related genes in this process has not been investigated. In this work, we use overexpression and structure-function

analyses to show that zebrafish Fer-1 tshz3b antagonizes Hox-dependent hindbrain segmentation. Ectopic Tshz3b perturbs the specification of rhombomere identities and leads to the caudal expansion of r1, the only rhombomere whose identity is specified independently of Hox function. This overexpression phenotype does not require the homeodomain and C-terminal zinc fingers that are unique to vertebrate Teashirt-related proteins, but does require that Tshz3b function as a repressor. Together, these results argue that the negative regulation of Hox PG 1-4 function is a conserved characteristic of Teashirt-related proteins. genesis 49: 725-742, 2011. (C) 2011 Wiley-Liss, Inc.”
“The administration of kainic acid (KA) causes seizures and produces neurodegeneration in hippocampal CA3 pyramidal cells. The present study investigated a possible role of acupuncture in reducing hippocampal cell death and inflammatory events, using a mouse model of kainic acid-induced epilepsy. Male C57BL/6 mice received acupuncture treatments at acupoint HT8 or in the tail area bilaterally once a day for 2 days and again immediately after an intraperitoneal injection of KA (30 mg/kg). HT8 is located on the palmar surface of the forelimbs, between the fourth and fifth metacarpal bones.

(C) 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 696-705, 2009.”
“Scaffold

proteins contain multiple protein protein interaction modules that physically assemble functionally find more related proteins into larger complexes. ZIPs [PKC (protein kinase C) zeta-interacting proteins] link the enzymatic activity of the atypical PKC isoforms PKC lambda/iota or PKC zeta to target proteins and are associated with neurodegenerative disorders. In the rat, alternative splicing generates three ZIP variants. Previously, we identified the ZIP3 transcript, containing 13 C-terminal amino acids encoded by intron 4, in the rat CNS (central nervous system). In the present study, we identified intronic polyadenylation signals in rat and human ZIP genes [known as SQSTM1 (sequestosome-1) in humans] and detected the corresponding ZIP3-like transcripts. In addition, we generated ZIP3-specific immune sera and observed expression of the protein in the brain and retina of the adult rat. In the retina, ZIP3 is present in nuclear layers where it co-localizes with PKC zeta. An immune serum recognizing all three ZIP isoforms labelled www.selleckchem.com/products/ipi-549.html the same cells as the newly generated ZIP3-specific antibodies and, in addition, stained both synaptic layers of the retina. There, ZIPs are localized in axon terminals of rod bipolar cells

that also contain ZIP-interacting PKC zeta and GABA(C) (gamma-aminobutyric acid type C) receptors. In summary, we detected ZIP3-like transcripts in rat- and human-derived samples and describe the expression of ZIP3 in the rat CNS.”
“Recent studies

have revealed that the maturation state of vessels in tumors, in addition to vascularity, is a critical determinant of tumor growth. The role of oxygen-dependent signaling pathways SN-38 in hypoxia-stimulated angiogenesis is well established, however, little is known about their impact on vessel maturation in tumors. Here, we have studied the function of the cellular oxygen sensor, factor inhibiting HIF-1 (FIH), which controls the activity of hypoxia-inducible factor-1. FIH silencing in mouse LM8 osteosarcoma stimulated angiogenesis but did not influence tumor growth. In contrast, FIH overexpression led to increased pericyte coverage of the tumor vasculature, reduced vessel leakiness and enhanced tumor growth. Vessel maturation was paralleled by up-regulation of platelet-derived growth factor (PDGF)-C in tumors and expression of PDGF receptor-a on pericytes. Ablation of PDGF-C in FIH-overexpressing tumor cells reduced pericyte coverage and tumor growth. Our data suggest that FIH-mediated PDGF-C induction in LM8 osteosarcoma stimulates the recruitment of PDGFR-a positive pericytes to the tumor vasculature, leading to vessel maturation and enhanced tumor growth.

Al2O3 dielectrics grown at three different temperatures of 700, 900, and 1000 degrees C were analyzed and compared. A low temperature GaN cap layer grown atop Al2O3 enabled a high success rate in the atom probe experiments. The Al2O3/GaN interfaces were found to be intermixed with Ga, N, and O over the distance of a few nm. Impurity measurements data showed that the 1000 degrees C sample contains higher amounts of C (4 x 10(19)/cm(3)) and

lower amounts of H (7 x 10(19)/cm(3)), whereas the 700 degrees C sample exhibits lower C impurities ( smaller than 10(17)/cm(3)) and higher H incorporation BLZ945 solubility dmso (2.2 x 10(20)/cm(3)). On comparing with Al2O3 grown by atomic layer deposition (ALD), it was found that the MOCVD Al2O3/GaN interface is comparatively abrupt. Scanning transmission electron microscopy data showed that the 900 degrees C and 1000 degrees C MOCVD films exhibit polycrystalline nature, while the ALD films were found to be amorphous. (C) 2014 AIP Publishing LLC.”
“Purpose of the study The aim of this study is to describe clinical and radiological outcomes as well as accompanying complications in a series of consecutive lateral transpsoas approaches (XLIF). Materials and methods A retrospective study of 39 patients treated for degenerative see more and post-traumatic lumbar diseases was carried out. Functional status, leg and back pain and radiological outcomes

were evaluated pre and post-operatively using the Oswestry disability index score (ODI) visual analog scales (VAS) and X-ray studies. Results Mean follow-up was 16 months (range 12-24 months). Mean improvement in back and leg pain on VAS was 6.08 (p smaller than 0.01) and 2.77 (p smaller than 0.01), respectively. Mean improvement in the ODI score was 38 (p smaller than 0.01). Increases in lumbar lordosis (32.8 degrees-39.2 degrees, p smaller than 0.05) and disc height (3.6-4.8 mm, p smaller than 0.05) were noted in the post-operative. Mild, transient strength deficit of the quadriceps muscle was also noted in

ten cases with complete regression. Conclusions XLIF proved to be a safe, effective, minimally invasive technique that allows valid arthrodesis to be carried out. Patients achieved check details positive clinical outcomes and satisfactory fusion rates, with sustained restoration of lordosis, spinal alignment and disc height.”
“Using sex pheromone traps baited with 1 mg of Z, E-7-11-hexadecadien-l-yl acetate (or HDA), observations of male adult presence and dispersion of the Angoumois grain moth, Sitotroga cerealella (Olivier) (Lepidoptera Gelechiidae), in warehouse and in field-plots were carried out. The studies were realised during 2012 and 2013 in a conventional small-farm of 10.5 ha located in hilly areas of Benevento, Campania region, Central-Southern Italy. The farm was divided into plots as follows: nursery truffle plants, vineyard, spring wheat, clover, oak grove, corn, tobacco, oats, barley, and olive grove. According to the results, infestations of S.

Pseudo-equilibrium in the brain was reached similar to 45 min post-injection. Metabolite analysis of [F-18]TZ3108 in NHP blood and rodent blood and brain revealed that

similar to 70% parent remained in the plasma of NHPs 60 min post-injection and the major radiometabolite did not cross the blood-brain barrier in rats. In summary, the potent, selective and metabolically stable sigma(1) specific radioligand [F-18]TZ3108 represents a potentially useful PET radioligand for quantifying the sigma(1) AZD2014 datasheet receptor in the brain.”
“Background: Many persistent organic pollutants (POPs) accumulate readily in polar bears because of their position as apex predators in Arctic food webs. The pregnane X receptor (PXR, formally NR1I2, here proposed to be named promiscuous

xenobiotic receptor) is a xenobiotic sensor that is directly CB-839 concentration involved in metabolizing pathways of a wide range of environmental contaminants. Objectives: In the present study, we comparably assess the ability of 51 selected pharmaceuticals, pesticides and emerging contaminants to activate PXRs from polar bears and humans using an in vitro luciferase reporter gene assay. Results: We found that polar bear PXR is activated by a wide range of our test compounds (68%) but has a slightly more narrow ligand specificity than human PXR that was activated by 86% of the 51 test compounds. The majority Evofosfamide concentration of the agonists identified (70%) produces a stronger induction of the reporter gene via human PXR than via polar bear PXR, however with some notable and environmentally relevant exceptions. Conclusions: Due to the observed differences in

activation of polar bear and human PXRs, exposure of each species to environmental agents is likely to induce biotransformation differently in the two species. Bioinformatics analyses and structural modeling studies suggest that amino acids that are not part of the ligand-binding domain and do not interact with the ligand can modulate receptor activation. (C) 2015 The Authors. Published by Elsevier Inc.”
“Navder KP, He Q, Zhang X, He S, Gong L, Sun Y, Deckelbaum RJ, Thornton J, Gallagher D. Relationship between body mass index and adiposity in prepubertal children: ethnic and geographic comparisons between New York City and Jinan City (China). J Appl Physiol 107: 488-493, 2009. First published June 18, 2009; doi: 10.1152/japplphysiol.00086.2009.-Body mass index (BMI) is often used as a surrogate estimate of percent body fat in epidemiological studies. This study tested the hypothesis that BMI is representative of body fatness independent of age, sex, ethnicity, and geographic location in prepubertal children.

01). Furthermore, HGF and its mRNA expression significantly increased in the drug intervention group (P<0.01), and expression in the high-dose group was significantly higher compared with that of the low-dose group (P<0.01), but similar to that of the fosinopril group (P>0.05). The levels of BUN decreased in the drug intervention group; however, no significant differences were determined in Scr, ALT and AST levels. Herba centellae may have inhibited MCP-1 and its mRNA expression through the upregulation

of HGF and its mRNA expression, in order to achieve resistance to TIF without showing evident hepatorenal toxicity.”
“Dolichoectasia describes the elongation, dilatation and tortuosity of an arterial vessel. In adults, clinical presentation of basilar see more dolichoectasia (BD) is most often with ischaemic stroke. True BD has been very rarely reported in childhood, but the implication is of a congenital susceptibility.\n\nWe describe two cases of infants with BD complicated by brainstem ischaemia.\n\nThis first description of childhood BD associated with ischaemic infarction adds to the understanding of this rarely reported arteriopathy.”
“While the short-term efficacy of intravesical hyaluronan for bladder pain syndrome/interstitial cystitis (BPS/IC) has been demonstrated, no data exist on the long-term outcome of this therapy.\n\nSeventy

SCH727965 BPS/IC patients treated with intravesical hyaluronan therapy from 2001 to 2003 were asked to rate their present status of bladder symptoms on a visual analog scale.\n\nForty-eight of 70 patients responded after a mean follow-up of 4.9 years. The average initial VAS score of 8.15 had been reduced to 2.71 after therapy and further to 2.14 5 years later. Fifty percent of patients (24/48)

reported complete bladder symptom remission at 5 years follow-up without any additional therapy; 41.7% (20/48) with symptom recurrence this website was improved with hyaluronan maintenance therapy. No improvement was reported by four patients.\n\nBesides a high rate of acute symptom remission, intravesical hyaluronan also shows long-term efficacy in a considerable number of BPS/IC patients.”
“The main objective of this work was to develop a protocol for the detection and quantification of ochratoxin A (OTA) to be used directly in food commodities, where sensitivity and robustness are critical factors. In this study, the contamination of wine grapes (var. Merlot) by OTA producer Aspergillus carbonarius was detected by PCR on asymptomatic grape berries. Four varieties of Vitis vinifera harvested directly from the field were used in the PCR-based assay. In the experiments, A. carbonarius was used to develop the PCR method, and Aspergillus niger strain 7096 and other species isolated from grapes were also used to test the specificity of the method presented below.

Additionally, we observed contrasting patterns of phenology between persistent and ephemeral invasive populations, with successful invaders exhibiting delayed annual peaks in population abundance. Two invasive zooplanktersthe copepod Pseudodiaptomus forbesi and larval Asian clam Corbicula flumineadominate the zooplankton community in Selleck EPZ5676 late summer and early autumn. Likewise, our results support conclusions from a growing body of literature that delayed phenology may be a key functional

trait for successful invaders.”
“HER2-specific affibody molecules in different formats have previously been shown to be useful tumor targeting agents for radionuclide-based imaging and therapy applications, but their biological effect on tumor cells is not well known. In this study, two dimeric ((Z(HER2:4))(2) and (Z(HER2:342))(2)) and one monomeric (Z(HER2:342)) HER2-specific affibody molecules are investigated with respect to biological activity. Both (Z(HER2:4))(2) and www.selleckchem.com/products/crenolanib-cp-868596.html (Z(HER2:342))(2) were found to decrease the growth rate of SKBR-3 cells to the same extent as the antibody trastuzumab. When the substances were removed, the cells treated with the dimeric affibody molecules continued to be growth suppressed while the cells treated

with trastuzumab immediately resumed normal proliferation. The effects of Z(HER2:342) were minor on both proliferation and cell signaling. The dimeric

https://www.selleckchem.com/products/prt062607-p505-15-hcl.html (Z(HER2:4))(2) and (Z(HER2:342))(2) both reduced growth of SKBR-3 cells and may prove therapeutically useful either by themselves or as carriers of radionuclides or other cytotoxic agents. (C) 2008 Elsevier Inc. All rights reserved.”
“Background: Chemo-resistance to cisplatin-centered cancer therapy is a major obstacle to effective disease treatment. Recently, salinomycin was proven to be highly-effective for the elimination of cancer stem cells both in vitro and in vivo. The objective of the present study was to evaluate the anticancer properties of salinomycin in cisplatin-resistant ovarian cancer cells (A2780cis). Materials and Methods: The tetrazolium dye (MT7′) assay was used to determine cell viability. Flow cytometric analysis was performed to analyze the effect on cell cycle and apoptosis. The expression of apoptosis-related proteins was evaluated by western blot analysis. Results: Cell viability was significantly reduced by salinomycin treatment in a dose-dependent manner. Flow cytometry showed an increase in sub-G(1) phase cells. Salinomycin increased the expression of death receptor-5 (DR5), caspase-8 and Fas-associated protein with death domain (FADD). A decline in the expression of FLICE-like inhibitory protein (FLIP), activation of caspase-3 and increased poly ADP-ribose polymerase (PARP) cleavage, triggered apoptosis.

We evaluated the association between socioeconomic status and the incidence of sudden cardiac arrest, a condition that accounts for a substantial proportion of cardiovascular-related deaths, in seven large North American urban populations.\n\nMethods: Using a population-based registry, we collected data on out-of-hospital sudden cardiac arrests occurring at home or at a residential institution from Apr. 1, 2006, to Mar. 31, 2007. We limited the analysis to cardiac arrests in seven metropolitan areas in the United States (Dallas, Texas; Pittsburgh, Pennsylvania;

Portland, Oregon; and Seattle-King County, Washington) and Canada (Ottawa and Toronto, Ontario; and Vancouver, British Columbia). Each incident was linked to a census tract; tracts were classified into quartiles of median household income.\n\nResults: A total of 9235 sudden cardiac arrests were included in the analysis. For all Kinase Inhibitor Library cell assay sites combined, the incidence of sudden cardiac arrest in the lowest socioeconomic quartile was nearly double that in the highest quartile (incidence rate ratio [IRR] 1.9, 95% confidence interval [CI] 1.8-2.0). This disparity was greater among people less than 65 years old (IRR 2.7, 95% CI 2.5-3.0) than among those 65 or older (IRR 1.3, 95% CI 1.2-1.4). After adjustment for study site and for population age structure of each census

tract, the disparity across socio economic quartiles for all ages combined was greater in the United States (IRR 2.0, 95% CI 1.9-2.2)

than in Canada (IRR selleck chemicals llc 1.8, 95% CI 1.6-2.0) (p < 0.001 for interaction).\n\nInterpretation: The incidence of sudden cardiac arrest at home or at a residential institution was higher in poorer neighbourhoods of the US and Canadian sites studied, click here although the association was attenuated in Canada. The disparity across socioeconomic quartiles was greatest among people younger than 65. The association be tween socio economic status and incidence of sudden cardiac arrest merits consideration in the development of strategies to improve survival from sudden cardiac arrest, and possibly to identify opportunities for prevention.”
“Background: Therapeutic hypothermia (TH, 30 degrees C) protects the brain from hypoxic injury. However, TH may potentiate the occurrence of lethal ventricular fibrillation (VF), although the mechanism remains unclear. The present study explored the hypothesis that TH enhances wavebreaks during VF and Si pacing, facilitates pacing-induced spatially discordant alternans (SDA), and increases the vulnerability of pacing-induced VF\n\nMethods and Results: Using an optical mapping system, epicardial activations of VF were studied in 7 Langendorff-perfused isolated rabbit hearts at baseline (37 degrees C), TH (30 degrees C), and rewarming (37 degrees C). Action potential duration (APD)/conduction velocity (CV) restitution and APD alternans (n=6 hearts) were determined by S1 pacing at these 3 stages.