bluuebunny/crossref_metadata_2025 huggingface dataset:
Antifibrotic properties of c-Ski and its regulation of cardiac myofibroblast phenotype and contractility
Authors: Cunnington Ryan H. , Wang Baiqiu , Ghavami Saeid , Bathe Krista L. , Rattan Sunil G. , Dixon Ian M. C.
Published: October 2010

Cardiac myofibroblasts are key players in chronic remodeling of the cardiac extracellular matrix, which is mediated in part by elevated transforming growth factor-β1 (TGF-β1). The c-Ski proto-oncoprotein has been shown to modify TGF-β1 post-receptor signaling through receptor-activated Smads (R-Smads); however, little is known about how c-Ski regulates fibroblast phenotype and function. We sought to elucidate the function of c-Ski in primary cardiac myofibroblasts using a c-Ski overexpression system. Cardiac myofibroblasts expressed three forms of c-Ski with the predominant band at 105 kDa, and adenoviral c-Ski treatment resulted in overexpression of 95-kDa c-Ski in cellular nuclei. Exogenous c-Ski led to significant inhibition of type I collagen secretion and myofibroblast contractility using two-dimensional semifloating gel contraction assay in both basal and with TGF-β1 (10 ng/ml for 24 h) stimulation. Overexpressed c-Ski did not inhibit nuclear translocation of phosphorylated R-Smad2, despite their binding, as demonstrated by immunoprecipitation. Acute treatment of primary myofibroblasts with TGF-β1 in vitro revealed a marked nuclear shuttling of c-Ski at 24 and 48 h following stimulation. Remarkably, overexpression of c-Ski led to a stepwise reduction of the myofibroblast marker α-smooth muscle actin with increasing multiplicity of infection, and these results indicate that 95-kDa c-Ski overexpression may effect a loss of the myofibroblastic phenotype. Furthermore, adenovirus (Ad) for hemagglutinin-tagged c-Ski infection led to a reduction in the number of myofibroblasts versus Ad-LacZ-infected and uninfected controls, due to induction of apoptosis. Finally, we observed a significant increase in 105-kDa c-Ski in the cytosolic fraction of cells of the infarct scar and adjacent remnant myocardium vs. noninfarcted controls.
Effect of denervation-induced muscle disuse on mitochondrial protein import
Authors: Singh Kaustabh , Hood David A.
Published: October 2010

This study determined whether muscle disuse affects mitochondrial protein import and whether changes in protein import are related to mitochondrial content and function. Protein import was measured using a model of unilateral peroneal nerve denervation in rats for 3 ( n = 10), 7 ( n = 12), or 14 ( n = 14) days. We compared the import of preproteins into the matrix of subsarcolemmal (SS) and intermyofibrillar (IMF) mitochondria isolated from the denervated and the contralateral control tibialis anterior muscles. Denervation led to 50% and 29% reductions in protein import after 14 days of disuse in SS and IMF mitochondria, respectively. This was accompanied by significant decreases in mitochondrial state 3 respiration, muscle mass, and whole muscle cytochrome c oxidase activity. To investigate the mechanisms involved, we assessed disuse-related changes in 1) protein import machinery components and 2) mitochondrial function, reflected by respiration and reactive oxygen species (ROS) production. Denervation significantly reduced the expression of translocases localized in the inner membrane (Tim23), outer membrane (Tom20), and mitochondrial heat shock protein 70 (mtHsp70), especially in the SS subfraction. Denervation also resulted in elevated ROS generation, and exogenous ROS was found to markedly reduce protein import. Thus our data indicate that protein import kinetics are closely related to alterations in mitochondrial respiratory capacity ( r = 0.95) and are negatively impacted by ROS. Deleterious changes in the protein import system likely facilitate the reduction in mitochondrial content and the increase in organelle dysfunction (i.e., increased ROS production and decreased respiration) during chronic disuse, which likely contribute to the activation of degradative pathways leading to muscle atrophy.
Coffee polyphenols suppress diet-induced body fat accumulation by downregulating SREBP-1c and related molecules in C57BL/6J mice
Authors: Murase Takatoshi , Misawa Koichi , Minegishi Yoshihiko , Aoki Masafumi , Ominami Hideo , Suzuki Yasuto , Shibuya Yusuke , Hase Tadashi
Published: October 2010

The prevalence of obesity is increasing globally, and obesity is a major risk factor for type 2 diabetes and cardiovascular disease. We investigated the effects of coffee polyphenols (CPP), which are abundant in coffee and consumed worldwide, on diet-induced body fat accumulation. C57BL/6J mice were fed either a control diet, a high-fat diet, or a high-fat diet supplemented with 0.5 to 1.0% CPP for 2–15 wk. Supplementation with CPP significantly reduced body weight gain, abdominal and liver fat accumulation, and infiltration of macrophages into adipose tissues. Energy expenditure evaluated by indirect calorimetry was significantly increased in CPP-fed mice. The mRNA levels of sterol regulatory element-binding protein (SREBP)-1c, acetyl-CoA carboxylase-1 and -2, stearoyl-CoA desaturase-1, and pyruvate dehydrogenase kinase-4 in the liver were significantly lower in CPP-fed mice than in high-fat control mice. Similarly, CPP suppressed the expression of these molecules in Hepa 1–6 cells, concomitant with an increase in microRNA-122. Structure-activity relationship studies of nine quinic acid derivatives isolated from CPP in Hepa 1–6 cells suggested that mono- or di-caffeoyl quinic acids (CQA) are active substances in the beneficial effects of CPP. Furthermore, CPP and 5-CQA decreased the nuclear active form of SREBP-1, acetyl-CoA carboxylase activity, and cellular malonyl-CoA levels. These findings indicate that CPP enhances energy metabolism and reduces lipogenesis by downregulating SREBP-1c and related molecules, which leads to the suppression of body fat accumulation.
Induction of ketosis in rats fed low-carbohydrate, high-fat diets depends on the relative abundance of dietary fat and protein
Authors: Bielohuby Maximilian , Menhofer Dominik , Kirchner Henriette , Stoehr Barbara J. M. , Müller Timo D. , Stock Peggy , Hempel Madlen , Stemmer Kerstin , Pfluger Paul T. , Kienzle Ellen , Christ Bruno , Tschöp Matthias H. , Bidlingmaier Martin
Published: October 2010

Low-carbohydrate/high-fat diets (LC-HFDs) in rodent models have been implicated with both weight loss and as a therapeutic approach to treat neurological diseases. LC-HFDs are known to induce ketosis; however, systematic studies analyzing the impact of the macronutrient composition on ketosis induction and weight loss success are lacking. Male Wistar rats were pair-fed for 4 wk either a standard chow diet or one of three different LC-HFDs, which only differed in the relative abundance of fat and protein (percentages of fat/protein in dry matter: LC-75/10; LC-65/20; LC-55/30). We subsequently measured body composition by nuclear magnetic resonance (NMR), analyzed blood chemistry and urine acetone content, evaluated gene expression changes of key ketogenic and gluconeogenic genes, and measured energy expenditure (EE) and locomotor activity (LA) during the first 4 days and after 3 wk on the respective diets. Compared with chow, rats fed with LC-75/10, LC-65/20, and LC-55/30 gained significantly less body weight. Reductions in body weight were mainly due to lower lean body mass and paralleled by significantly increased fat mass. Levels of β-hydroxybutyate were significantly elevated feeding LC-75/10 and LC-65/20 but decreased in parallel to reductions in dietary fat. Acetone was about 16-fold higher with LC-75/10 only ( P < 0.001). In contrast, rats fed with LC-55/30 were not ketotic. Serum fibroblast growth factor-21, hepatic mRNA expression of hydroxymethylglutaryl-CoA-lyase, peroxisome proliferator-activated receptor-γ coactivator-1α, and peroxisome proliferator-activated receptor-γ coactivator-1β were increased with LC-75/10 only. Expression of phospho enolpyruvate carboxykinase and glucose-6-phosphatase was downregulated by 50–70% in LC-HF groups. Furthermore, EE and LA were significantly decreased in all groups fed with LC-HFDs after 3 wk on the diets. In rats, the absence of dietary carbohydrates per se does not induce ketosis. LC-HFDs must be high in fat, but also low in protein contents to be clearly ketogenic. Independent of the macronutrient composition, LC-HFD-induced weight loss is not due to increased EE and LA.
Impact of electro-acupuncture and physical exercise on hyperandrogenism and oligo/amenorrhea in women with polycystic ovary syndrome: a randomized controlled trial
Authors: Jedel Elizabeth , Labrie Fernand , Odén Anders , Holm Göran , Nilsson Lars , Janson Per Olof , Lind Anna-Karin , Ohlsson Claes , Stener-Victorin Elisabet
Published: October 2010

Polycystic ovary syndrome (PCOS), the most common endocrine disorder in women of reproductive age, is characterized by hyperandrogenism, oligo/amenorrhea, and polycystic ovaries. We aimed to determine whether low-frequency electro-acupuncture (EA) would decrease hyperandrogenism and improve oligo/amenorrhea more effectively than physical exercise or no intervention. We randomized 84 women with PCOS, aged 18–37 yr, to 16 wk of low-frequency EA, physical exercise, or no intervention. The primary outcome measure changes in the concentration of total testosterone (T) at week 16 determined by gas and liquid chromatography-mass spectrometry was analyzed by intention to treat. Secondary outcome measures were changes in menstrual frequency; concentrations of androgens, estrogens, androgen precursors, and glucuronidated androgen metabolites; and acne and hirsutism. Outcomes were assessed at baseline, after 16 wk of intervention, and after a 16-wk follow-up. After 16 wk of intervention, circulating T decreased by −25%, androsterone glucuronide by −30%, and androstane-3α,17β-diol-3-glucuronide by −28% in the EA group ( P = 0.038, 0.030, and 0.047, respectively vs. exercise); menstrual frequency increased to 0.69/month from 0.28 at baseline in the EA group ( P = 0.018 vs. exercise). After the 16-wk follow-up, the acne score decreased by −32% in the EA group ( P = 0.006 vs. exercise). Both EA and exercise improved menstrual frequency and decreased the levels of several sex steroids at week 16 and at the 16-wk follow-up compared with no intervention. Low-frequency EA and physical exercise improved hyperandrogenism and menstrual frequency more effectively than no intervention in women with PCOS. Low-frequency EA was superior to physical exercise and may be useful for treating hyperandrogenism and oligo/amenorrhea.
Acute starvation alters lipopolysaccharide-induced fever in leptin-dependent and -independent mechanisms in rats
Authors: Inoue Wataru , Luheshi Giamal N.
Published: October 2010

A decrease in leptin levels with the onset of starvation triggers a myriad of physiological responses including immunosuppression and hypometabolism/hypothermia, both of which can counteract the fever response to pathogens. Here we examined the role of leptin in LPS-induced fever in rats that were fasted for 48 h prior to inflammation with or without leptin replacement (12 μg/day). The preinflammation fasting alone caused a progressive hypothermia that was almost completely reversed by leptin replacement. The LPS (100 μg/kg)-induced elevation in core body temperature ( T core) was attenuated in the fasted animals at 2–6 h after the injection, an effect that was not reversed by leptin replacement. Increasing the LPS dose to 1,000 μg/kg caused a long-lasting fever that remained unabated for up to 36 h after the injection in the fed rats. This sustained response was strongly attenuated in the fasted rats whose T core started to decrease by 18 h after the injection. Leptin replacement almost completely restored the prolonged fever. The attenuation of the prolonged fever in the fasted animals was accompanied by the diminution of proinflammatory PGE2 in the cerebrospinal fluid and mRNA of proopiomelanocortin (POMC) in the hypothalamus. Leptin replacement prevented the fasting-induced reduction of POMC but not PGE2. Moreover, the leptin-dependent fever maintenance correlated closely with hypothalamic POMC levels ( r = 0.77, P < 0.001). These results suggest that reduced leptin levels during starvation attenuate the sustained fever response by lowering hypothalamic POMC tone but not PGE2 synthesis.
VEGF-modified human embryonic mesenchymal stem cell implantation enhances protection against cisplatin-induced acute kidney injury
Authors: Yuan Li , Wu Min-Juan , Sun Hong-Yu , Xiong Jun , Zhang Yi , Liu Chun-Yan , Fu Li-Li , Liu Dong-Mei , Liu Hou-Qi , Mei Chang-Lin
Published: October 2010

The implantation of mesenchymal stem cells (MSC) has been reported as a new technique to restore renal tubular structure and improve renal function in acute kidney injury (AKI). Vascular endothelial growth factor (VEGF) plays an important role in the renoprotective function of MSC. Whether upregulation of VEGF by a combination of MSC and VEGF gene transfer could enhance the protective effect of MSC in AKI is not clear. We investigated the effects of VEGF-modified human embryonic MSC (VEGF-hMSC) in healing cisplatin-injured renal tubular epithelial cells (TCMK-1) with a coculture system. We found that TCMK-1 viability declined 3 days after cisplatin pretreatment and that coculture with VEGF-hMSC enhanced cell protection via mitogenic and antiapoptotic actions. In addition, administration of VEGF-hMSC in a nude mouse model of cisplatin-induced kidney injury offered better protective effects on renal function, tubular structure, and survival as represented by increased cell proliferation, decreased cellular apoptosis, and improved peritubular capillary density. These data suggest that VEGF-modified hMSC implantation could provide advanced benefits in the protection against AKI by increasing antiapoptosis effects and improving microcirculation and cell proliferation.
mTORC1/2 and rapamycin in female Han:SPRD rats with polycystic kidney disease
Authors: Belibi Franck , Ravichandran Kameswaran , Zafar Iram , He Zhibin , Edelstein Charles L.
Published: October 2010

Rapamycin slows disease progression in the male Han:SPRD (Cy/+) rat with polycystic kidney disease (PKD). The aim of this study was to determine the effect of rapamycin on PKD and the relative contributions of the proproliferative mammalian target of rapamycin complexes 1 and 2 (mTORC1 and mTORC2) in female Cy/+ rats. Female Cy/+ rats were treated with rapamycin from 4 to 12 wk of age. In vehicle-treated Cy/+ rats, kidney volume increased by 40% and cyst volume density (CVD) was 19%. Phosphorylated S6 (p-S6) ribosomal protein, a marker of mTORC1 activity, was increased in Cy/+ rats compared with normal littermate controls (+/+) and decreased by rapamycin. Despite activation of mTORC1 in female Cy/+ rats, rapamycin had no effect on kidney size, CVD, number of PCNA-positive cystic tubular cells, caspase-3 activity, or the number of terminal deoxynucleotidyl transferase dUTP-mediated nick-end label-positive apoptotic cells. To determine a reason for the lack of effect of rapamycin, we studied the mTORC2 signaling pathway. On immunoblot of kidney, phosphorylated (Ser473) Akt (p-Akt), a marker of mTORC2 activity, was increased in female Cy/+ rats treated with rapamycin. Phosphorylated (Ser657) PKCα, a substrate of mTORC2, was unaffected by rapamycin in females. In contrast, in male rats, where rapamycin significantly decreases PKD, p-Akt (Ser473) was decreased by rapamcyin. PKCα (Ser657) was increased in male Cy/+ rats but was unaffected by rapamycin. In summary, in female Cy/+ rats, rapamycin had no effect on PKD and proproliferative p-Akt (Ser473) activity was increased by rapamycin. There were differential effects of rapamycin on mTORC2 signaling in female vs. male Cy/+ rats.
Ribosomal biogenesis induction by high glucose requires activation of upstream binding factor in kidney glomerular epithelial cells
Authors: Mariappan Meenalakshmi M. , D'Silva Kristin , Lee Myung Ja , Sataranatarajan Kavithalakshmi , Barnes Jeffrey L. , Choudhury Goutam Ghosh , Kasinath Balakuntalam S.
Published: October 2010

Diabetes promotes protein synthesis to induce kidney hypertrophy and increase renal matrix proteins. Increased capacity for mRNA translation by way of ribosomal biogenesis facilitates sustained stimulation of protein synthesis. We tested the hypothesis that high glucose induces ribosomal biogenesis as indicated by an increase in rRNA synthesis in the setting of augmented protein synthesis. High glucose (30 mM) increased global protein synthesis, expression of matrix proteins, laminin γ1and fibronectin, and rDNA transcription in glomerular epithelial cells (GECs) compared with 5 mM glucose. High glucose induced Ser388phosphorylation of upstream binding factor (UBF), an rDNA transcription factor, along with increased phosphorylation of Erk and p70S6 kinase. Inactivation of Erk and p70S6 kinase either by their respective chemical inhibitors or by expression of their inactive mutant constructs blocked high-glucose-induced UBF phosphorylation. High glucose reduced nuclear content of p19ARF and promoted dissolution of inactive UBF-p19ARF complex. High glucose also promoted association of UBF with RPA194, a subunit of RNA polymerase I. Inhibition of Erk, p70S6 kinase, and UBF1 by transfecting GECs with their respective inactive mutants abolished laminin γ1synthesis, protein synthesis, and rDNA transcription. Renal cortex from type 1 diabetic rats and type 2 diabetic db/ db mice showed increased phosphorylation of UBF, Erk, and p70S6 kinase coinciding with renal hypertrophy and onset of matrix accumulation. Our data suggest that augmented ribosome biogenesis occurs in an UBF-dependent manner during increased protein synthesis induced by high glucose in the GECs that correlates with UBF activation and renal hypertrophy in rodents with type 1 and type 2 diabetes.
Expression and distribution of transient receptor potential (TRP) channels in bladder epithelium
Authors: Yu Weiqun , Hill Warren G. , Apodaca Gerard , Zeidel Mark L.
Published: October 2010

The urothelium is proposed to be a sensory tissue that responds to mechanical stress by undergoing dynamic membrane trafficking and neurotransmitter release; however, the molecular basis of this function is poorly understood. Transient receptor potential (TRP) channels are ideal candidates to fulfill such a role as they can sense changes in temperature, osmolarity, and mechanical stimuli, and several are reported to be expressed in the bladder epithelium. However, their complete expression profile is unknown and their cellular localization is largely undefined. We analyzed expression of all 33 TRP family members in mouse bladder and urothelium by RT-PCR and found 22 specifically expressed in the urothelium. Of the latter, 10 were chosen for closer investigation based on their known mechanosensory or membrane trafficking functions in other cell types. Western blots confirmed urothelial expression of TRPC1, TRPC4, TRPV1, TRPV2, TRPV4, TRPM4, TRPM7, TRPML1, and polycystins 1 and 2 (PKD1 and PKD2) proteins. We further defined the cellular and subcellular localization of all 10 TRP channels. TRPV2 and TRPM4 were prominently localized to the umbrella cell apical membrane, while TRPC4 and TRPV4 were identified on their abluminal surfaces. TRPC1, TRPM7, and TRPML1 were localized to the cytoplasm, while PKD1 and PKD2 were expressed on the apical and basolateral membranes of umbrella cells as well as in the cytoplasm. The cellular location of TRPV1 in the bladder has been debated, but colocalization with neuronal marker calcitonin gene-related peptide indicated clearly that it is present on afferent neurons that extend into the urothelium, but may not be expressed by the urothelium itself. These findings are consistent with the hypothesis that the urothelium acts as a sentinel and by expressing multiple TRP channels it is likely it can detect and presumably respond to a diversity of external stimuli and suggest that it plays an important role in urothelial signal transduction.
Oxidative stress alters renal D1 and AT1 receptor functions and increases blood pressure in old rats
Authors: Chugh Gaurav , Lokhandwala Mustafa F. , Asghar Mohammad
Published: October 2010

Aging is associated with an increase in oxidative stress and blood pressure (BP). Renal dopamine D1 (D1R) and angiotensin II AT1 (AT1R) receptors maintain sodium homeostasis and BP. We hypothesized that age-associated increase in oxidative stress causes altered D1R and AT1R functions and high BP in aging. To test this, adult (3 mo) and old (21 mo) Fischer 344 × Brown Norway F1 rats were supplemented without/with antioxidant tempol followed by determining oxidative stress markers (urinary antioxidant capacity, proximal tubular NADPH- gp91phox, and plasma 8-isoprostane), D1R and AT1R functions, and BP. The D1R and AT1R functions were determined by measuring diuretic and natriuretic responses to D1R agonist (SKF-38393; 1 μg·kg−1·min−1iv) and AT1R antagonist (candesartan; 10 μg/kg iv), respectively. We found that the total urinary antioxidant capacity was lower in old rats, which increased with tempol treatment. In addition, tempol decreased the elevated NADPH- gp91phoxand 8-isoprostane levels in old rats. Systolic, diastolic, and mean arterial BPs were higher in old rats and were reduced by tempol. Although SKF-38393 produced diuresis in both adult and old rats, urinary sodium excretion (UNaV) increased only in adult rats. While candesartan increased diuresis and UNaV in adult and old rats, the magnitude of response was greater in old rats. Tempol treatment in old rats reduced candesartan-induced increase in diuresis and UNaV. Our results demonstrate that diminished renal D1R and exaggerated AT1R functions are associated with high BP in old rats. Furthermore, oxidative stress may cause altered renal D1R and AT1R functions and high BP in old rats.
Physiological complexity and system adaptability: evidence from postural control dynamics of older adults
Authors: Manor Brad , Costa Madalena D. , Hu Kun , Newton Elizabeth , Starobinets Olga , Kang Hyun Gu , Peng C. K. , Novak Vera , Lipsitz Lewis A.
Published: October 2010

The degree of multiscale complexity in human behavioral regulation, such as that required for postural control, appears to decrease with advanced aging or disease. To help delineate causes and functional consequences of complexity loss, we examined the effects of visual and somatosensory impairment on the complexity of postural sway during quiet standing and its relationship to postural adaptation to cognitive dual tasking. Participants of the MOBILIZE Boston Study were classified into mutually exclusive groups: controls [intact vision and foot somatosensation, n = 299, 76 ± 5 (SD) yr old], visual impairment only (<20/40 vision, n = 81, 77 ± 4 yr old), somatosensory impairment only (inability to perceive 5.07 monofilament on plantar halluxes, n = 48, 80 ± 5 yr old), and combined impairments ( n = 25, 80 ± 4 yr old). Postural sway (i.e., center-of-pressure) dynamics were assessed during quiet standing and cognitive dual tasking, and a complexity index was quantified using multiscale entropy analysis. Postural sway speed and area, which did not correlate with complexity, were also computed. During quiet standing, the complexity index (mean ± SD) was highest in controls (9.5 ± 1.2) and successively lower in the visual (9.1 ± 1.1), somatosensory (8.6 ± 1.6), and combined (7.8 ± 1.3) impairment groups ( P = 0.001). Dual tasking resulted in increased sway speed and area but reduced complexity ( P < 0.01). Lower complexity during quiet standing correlated with greater absolute ( R = −0.34, P = 0.002) and percent ( R = −0.45, P < 0.001) increases in postural sway speed from quiet standing to dual-tasking conditions. Sensory impairments contributed to decreased postural sway complexity, which reflected reduced adaptive capacity of the postural control system. Relatively low baseline complexity may, therefore, indicate control systems that are more vulnerable to cognitive and other stressors.
Role of Neuronal Synchrony in the Generation of Evoked EEG/MEG Responses
Authors: Telenczuk Bartosz , Nikulin Vadim V. , Curio Gabriel
Published: October 2010

Evoked EEG/MEG responses are a primary real-time measure of perceptual and cognitive activity in the human brain, but their neuronal generator mechanisms are not yet fully understood. Arguments have been put forward in favor of either “phase-reset” of ongoing oscillations or “added-energy” models. Instead of advocating for one or the other model, here we show theoretically that the differentiation between these two generation mechanisms might not be possible if based solely on macroscopic EEG/MEG recordings. Using mathematical modeling, we show that a simultaneous phase reset of multiple oscillating neuronal (microscopic) sources contributing to EEG/MEG can produce evoked responses in agreement with both, the “added-energy” and the “phase-reset” model. We observe a smooth transition between the two models by just varying the strength of synchronization between the multiple microscopic sources. Consequently, because precise knowledge about the strength of microscopic ensemble synchronization is commonly not available in noninvasive EEG/MEG studies, they cannot, in principle, differentiate between the two mechanisms for macroscopic-evoked responses.
Bilateral Adaptation During Locomotion Following a Unilaterally Applied Resistance to Swing in Nondisabled Adults
Authors: Savin Douglas N. , Tseng Shih-Chiao , Morton Susanne M.
Published: October 2010

Human walking must be flexible enough to accommodate many contexts and goals. One form of this flexibility is locomotor adaptation: a practice-dependent alteration to walking occurring in response to some novel perturbing stimulus. Although studies have examined locomotor adaptation and its storage by the CNS in humans, it remains unclear whether altered movements occurring in the leg contralateral to a perturbation are caused by true practice-dependent adaptation or whether they are generated via feedback corrective mechanisms. To test this, we recorded leg kinematics and electromyography (EMG) from nondisabled adults as they walked on a treadmill before, during, and after a novel force was applied to one leg, which resisted its forward movement during swing phase. The perturbation produced kinematic changes to numerous walking parameters, including swing phase durations, step lengths, and hip angular excursions. Nearly all occurred bilaterally. Importantly, kinematic changes were gradually adjusted over a period of exposure to the perturbation and were associated with negative aftereffects on its removal, suggesting they were adjusted through a true motor adaptation process. In addition, increases in the EMG of both legs persisted even after the perturbation was removed, providing further evidence that the CNS made and stored changes to feedforward motor commands controlling each leg. Our results show evidence for a feedforward adaptation of walking involving the leg opposite a perturbation. This result may help support the application of locomotor adaptation paradigms in clinical rehabilitation interventions targeting recovery of symmetric walking patterns in a variety of patient populations.
Inhibitory and Disinhibitory Effects on I-Wave Facilitation in Motor Cortex
Authors: Cash R.F.H. , Ziemann U. , Thickbroom G. W.
Published: October 2010

A suprathreshold pulse of transcranial magnetic stimulation (TMS) delivered to human motor cortex results in a period of long-interval intracortical inhibition (LICI) followed by a briefer period of disinhibition (late cortical disinhibition [LCD]). Short-interval intracortical facilitation (SICF) is mediated by excitatory networks in the motor cortex responsible for the generation of the indirect (I-) wave volleys that are evoked by TMS at a periodicity of about 1.5 ms. Because the excitatory synaptic network responsible for SICF undergoes inhibitory regulation, we hypothesized that SICF will be modulated during periods of inhibition and disinhibition. In particular we were interested to know whether SICF was up-regulated during disinhibition, implying an increase in excitatory synaptic efficacy. We measured SICF, at a paired-pulse interval of 1.5 ms, at various times (100–300 ms) after a suprathreshold priming stimulus (PS) of sufficient strength to evoke LICI and LCD. We found that the strength of SICF was normal during LICI, but was increased during LCD by an average of 64%. SICF onset latency was reduced by one I-wave interval during LCD and was delayed by one I-wave interval during LICI. We conclude that disinhibition, rather than inhibition, modulates the excitatory neuronal networks that underlie SICF, whereas the I-wave targeted is modified by the presence of both inhibition and disinhibition and that there is therefore a dissociation between the strength and site of SICF interaction. The increase in SICF during disinhibition further indicates that this is a promising period to investigate or modulate excitatory synaptic networks while they are less constrained by ongoing levels of inhibition.
Neuronal Gap Junctions Are Required for NMDA Receptor–Mediated Excitotoxicity: Implications in Ischemic Stroke
Authors: Wang Yongfu , Denisova Janna V. , Kang Ki Sung , Fontes Joseph D. , Zhu Bao Ting , Belousov Andrei B.
Published: October 2010

N-methyl-d-aspartate receptors (NMDARs) play an important role in cell survival versus cell death decisions during neuronal development, ischemia, trauma, and epilepsy. Coupling of neurons by electrical synapses (gap junctions) is high or increases in neuronal networks during all these conditions. In the developing CNS, neuronal gap junctions are critical for two different types of NMDAR-dependent cell death. However, whether neuronal gap junctions play a role in NMDAR-dependent neuronal death in the mature CNS was not known. Using Fluoro-Jade B staining, we show that a single intraperitoneal administration of NMDA (100 mg/kg) to adult wild-type mice induces neurodegeneration in three forebrain regions, including rostral dentate gyrus. However, the NMDAR-mediated neuronal death is prevented by pharmacological blockade of neuronal gap junctions (with mefloquine, 30 mg/kg) and does not occur in mice lacking neuronal gap junction protein, connexin 36. Using Western blots, electrophysiology, calcium imaging, and gas chromatography–mass spectrometry in wild-type and connexin 36 knockout mice, we show that the reduced level of neuronal death in knockout animals is not caused by the reduced expression of NMDARs, activity of NMDARs, or permeability of the blood–brain barrier to NMDA. In wild-type animals, this neuronal death is not caused by upregulation of connexin 36 by NMDA. Finally, pharmacological and genetic inactivation of neuronal gap junctions in mice also dramatically reduces neuronal death caused by photothrombotic focal cerebral ischemia. The results indicate that neuronal gap junctions are required for NMDAR-dependent excitotoxicity and play a critical role in ischemic neuronal death.
Biochemical Signatures of Doppel Protein in Human Astrocytomas to Support Prediction in Tumor Malignancy
Authors: Rognoni Paola , Chiarelli Laurent R. , Comincini Sergio , Azzalin Alberto , Miracco Clelia , Valentini Giovanna
Published: October 2010

Doppel (Dpl) is a membrane-bound glycoprotein mainly expressed in the testis of adult healthy people. It is generally absent in the central nervous system, but its coding gene sequence is ectopically expressed in astrocytoma specimens and in derived cell lines. In this paper, we investigated the expression and the biochemical features of Dpl in a panel of 49 astrocytoma specimens of different WHO malignancy grades. As a result, Dpl was expressed in the majority of the investigated specimens (86%), also including low grade samples. Importantly, Dpl exhibited different cellular localizations and altered glycan moieties composition, depending on the tumor grade. Most low-grade astrocytomas (83%) showed a membrane-bound Dpl, like human healthy testis tissue, whereas the majority of high-grade astrocytomas (75%) displayed a cytosolic Dpl. Deglycosylation studies with N-glycosidase F and/or neuraminidase highlighted defective glycan moieties and an unexpected loss of sialic acid. To find associations between glial tumor progression and Dpl biochemical features, predictive bioinformatics approaches were produced. In particular, Decision tree and Nomogram analysis showed well-defined Dpl-based criteria that separately clustered low-and high-grade astrocytomas. Taken together, these findings show that in astrocytomas, Dpl undergoes different molecular processes that might constitute additional helpful tools to characterize the glial tumor progression.
Forebrain Ischemia Triggers GABAergic System Degeneration in Substantia Nigra at Chronic Stages in Rats
Authors: Lin B. , Levy S. , Raval A. P. , Perez-Pinzon M. A. , DeFazio R. A.
Published: October 2010

The long-term consequences of forebrain ischemia include delayed Parkinson's syndrome. This study revealed delayed neurodegeneration in the substantia nigra 8 weeks after 12.5 minutes of global ischemia in rat brain. Following neuronal loss of 30–40% in central and dorsolateral striatum at day 3, neuronal damage in the substantia nigra (SN) was assessed at 4–8 weeks using immunohistochemistry for glutamate decarboxylase 67 (GAD67), vesicular GABA transporter (VGAT), and calretinin (CR). At day 56, the optical density of GAD67-, but not VGAT-, immunoreactivity in substantia nigra pars reticulata (SNR)—significantly decreased. CR-neurons concentrated in substantia nigra pars compacta (SNC) were reduced by 27% from day 3 (n=5) to day 56 (n=7, ANOVA,p<.01). Movement coordination was impaired at day 56, as evaluated using beam-walking test (time-to-traverse5.6±1.2 sec versus11.8±5.4 sec; sham versus ischemia,p<.05,n=5, and 7, resp.). Our results demonstrate delayed impairment of the GABAergic system components in SN and associated with movement deficits after global ischemia.
Proteomic Signatures of the Zebrafish (Danio rerio) Embryo: Sensitivity and Specificity in Toxicity Assessment of Chemicals
Authors: Hanisch Karen , Küster Eberhard , Altenburger Rolf , Gündel Ulrike
Published: October 2010

Studies using embryos of the zebrafish Danio rerio (DarT) instead of adult fish for characterising the (eco-) toxic potential of chemicals have been proposed as animal replacing methods. Effect analysis at the molecular level might enhance sensitivity, specificity, and predictive value of the embryonal studies. The present paper aimed to test the potential of toxicoproteomics with zebrafish eleutheroembryos for sensitive and specific toxicity assessment. 2-DE-based toxicoproteomics was performed applying low-dose (EC10) exposure for 48 h with three-model substances Rotenone, 4,6-dinitro-o-cresol (DNOC) and Diclofenac. By multivariate “pattern-only” PCA and univariate statistical analyses, alterations in the embryonal proteome were detectable in nonetheless visibly intact organisms and treatment with the three substances was distinguishable at the molecular level. Toxicoproteomics enabled the enhancement of sensitivity and specificity of the embryonal toxicity assay and bear the potency to identify protein markers serving as general stress markers and early diagnosis of toxic stress.
Investigation of Antiangiogenic Tumor Therapy Potential of Microencapsulated HEK293 VEGF165b Producing Cells
Authors: Afkhami Fatemeh , Durocher Yves , Prakash Satya
Published: October 2010

To investigate the antiangiogenic potential of encapsulated VEGF165b producing HEK293 cells, Human Embryonic Kidney 293 (HEK293) cells were stably transfected to produce VEGF165b. Then they were encapsulated in alginate - polylysine -alginate (APA) microcapsules. VEGF165b productivity and viability of encapsulated cells were analyzed and compared with the non-encapsulated cells. Results showed that encapsulated cells proliferated and remained viable within the microcapsules throughout the 28-day period of the experiment. The quantity of VEGF165b increased from6.5±1.2 μg/ml at day 13 to13±0.96 μg/ml at day 16. Then it gradually dropped to5±1.2 μg/ml for the last 3 days period as measured at day 28. Production of VEGF165b from encapsulated and non-encapsulated cells was similar. The effect of VEGF165b harvested from encapsulated cells on Human Umbilical Vein Endothelial cells (HUVECs) proliferation were also examined.The same inhibitory effects on HUVECs proliferation was seen when the cells were incubated with a mixture of VEGF165b and a 2-fold VEGF165b or with VEGF165b and 2-fold excess VEGF165b released from encapsulated cells. Subcutaneous injection of microencapsulated VEGF165b producing cells in tumor site of nude mice resulted in the reduction of the number of vessels around the tumors.
Radiotherapy for Soft Tissue Sarcoma of the Proximal Lower Extremity
Authors: Prendergast Brendan , Fiveash John B. , Gibbs C. Parker , Scarborough Mark T. , Indelicato Daniel J.
Published: October 2010

Soft-tissue sarcoma (STS) is a histopathologically diverse group of tumors accounting for approximately 10,000 new malignancies in the US each year. The proximal lower extremity is the most common site for STS, accounting for approximately one-third of all cases. Coordinated multimodality management in the form of surgery and radiation is often critical to local control, limb preservation, and functional outcome. Based on a review of currently available Medline literature and professional experience, this paper provides an overview of the treatment of STS of the lower extremity with a particular focus on the modern role of radiotherapy.
Effect of Different Support Morphologies and Pt Particle Sizes in Electrocatalysts for Fuel Cell Applications
Authors: Sevjidsuren G. , Zils S. , Kaserer S. , Wolz A. , Ettingshausen F. , Dixon D. , Schoekel A. , Roth C. , Altantsog P. , Sangaa D. , Ganzorig Ch.
Published: October 2010

The performance of a low temperature fuel cell is strongly correlated with parameters like the platinum particle size, platinum dispersion on the carbon support, and electronic and protonic conductivity in the catalyst layer as well as its porosity. These parameters can be controlled by a rational choice of the appropriate catalyst synthesis and carbon support. Only recently, particular attention has been given to the support morphology, as it plays an important role for the formation of the electrode structure. Due to their significantly different structure, mesoporous carbon microbeads (MCMBs) and multiwalled carbon nanotubes (MWCNTs) were used as supports and compared. Pt nanoparticles were decorated on these supports using the polyol method. Their size was varied by different heating times during the synthesis, and XRD, TEM, SEM, CV, and single cell tests used in their detailed characterization. A membrane‐electrode assembly prepared with the MCMB did not show any activity in the fuel cell test, although the catalyst′s electrochemical activity was almost similar to the MWCNT. This is assumed to be due to the very dense electrode structure formed by this support material, which does not allow for sufficient mass transport.
Variations in Badger (Meles meles) Sett Microclimate: Differential Cub Survival between Main and Subsidiary Setts, with Implications for Artificial Sett Construction
Authors: Kaneko Yayoi , Newman Chris , Buesching Christina D. , Macdonald David W.
Published: October 2010

Maintaining homeothermy is essential for mammals, but has considerable energetic costs. In this study, we monitored the internal conditions of setts within five European badger (Meles meles) social groups during the cub-rearing season, that is, February to July, in 2004. Sett temperature showed substantial and significant variation over this period, while relative humidity remained stable throughout. Microclimate was least stable during the period for which cubs remain entirely below ground between February and April; however here the instrumented main sett demonstrated a much warmer and more stable temperature regime than did nearby subsidiary outliers. We thus postulate that the energy budget of reproducing females could be affected by even small temperature fluctuations, militating for optimal sett choice. For comparison we also report microclimatic data from two artificial setts and found them to be markedly inferior in terms of thermal insulative properties, suggesting that man-made setts may need more careful consideration in both thermal and spatial setts network in each territory to adequately compensate the loss (e.g., destruction due to development) of a natural sett, especially as a breeding den.
Raf-1 Activation Prevents Caspase 9 Processing Downstream of Apoptosome Formation
Authors: Cagnol Sébastien , Mansour Anna , Van Obberghen-Schilling Ellen , Chambard Jean-Claude
Published: October 2010

In many cell types, growth factor removal induces the release of cytochrome-c from mitochondria that leads to activation of caspase-9 in the apoptosome complex. Here, we show that sustained stimulation of the Raf-1/MAPK1,3 pathway prevents caspase-9 activation induced by serum depletion in CCL39/Raf-1:ER fibroblasts. The protective effect mediated by Raf-1 is sensitive to MEK inhibition that is sufficient to induce caspase-9 cleavage in exponentially growing cells. Raf-1 activation does not inhibit the release of cytochrome-c from mitochondria while preventing caspase-9 activation. Gel filtration chromatography analysis of apoptosome formationin cellsshows that Raf-1/MAPK1,3 activation does not interfere with APAF-1 oligomerization and recruitment of caspase 9. Raf-1-mediated caspase-9 inhibition is sensitive to emetine, indicating that the protective mechanism requires protein synthesis. However, the Raf/MAPK1,3 pathway does not regulate XIAP. Taken together, these results indicate that the Raf-1/MAPK1,3 pathway controls an apoptosis regulator that prevents caspase-9 activation in the apoptosome complex.
Inhibitory Effects of Terminalia catappa on UVB‐Induced Photodamage in Fibroblast Cell Line
Authors: Wen Kuo-Ching , Shih I-Chen , Hu Jhe-Cyuan , Liao Sue-Tsai , Su Tsung-Wei , Chiang Hsiu-Mei
Published: October 2010

This study investigated whether Terminalia catappa L. hydrophilic extract (TCLW) prevents photoaging in human dermal fibroblasts after exposure to UVB radiation. TCLW exhibited DPPH free radical scavenging activity and protected erythrocytes against AAPH‐induced hemolysis. In the gelatin digestion assay, the rates of collagenase inhibition by TCL methanol extract, TCLW, and its hydrolysates were greater than 100% at the concentration of 1 mg/mL. We found that serial dilutions of TCLW (10–500 μg/mL) inhibited collagenase activity in a dose‐dependent manner (82.3% to 101.0%). However, TCLW did not significantly inhibit elastase activity. In addition, TCLW inhibited MMP‐1 and MMP‐9 protein expression at a concentration of 25 μg/mL and inhibited MMP‐3 protein expression at a concentration of 50 μg/mL. TCLW also promoted the protein expression of type I procollagen. We also found that TCLW attenuated the expression of MMP‐1, ‐3, and ‐9 by inhibiting the phosphorylation of ERK, JNK, and p38. These findings suggest that TCLW increases the production of type I procollagen by inhibiting the activity of MMP‐1, ‐3 and ‐9, and, therefore, has potential use in anti‐aging cosmetics.
Phase I Study of NK012, a Novel SN-38–Incorporating Micellar Nanoparticle, in Adult Patients with Solid Tumors
Authors: Hamaguchi Tetsuya , Doi Toshihiko , Eguchi-Nakajima Takako , Kato Ken , Yamada Yasuhide , Shimada Yasuhiro , Fuse Nozomu , Ohtsu Atsushi , Matsumoto Shin-ichi , Takanashi Masaya , Matsumura Yasuhiro
Published: October 2010

Purpose: We conducted a first-in-human phase I study to determine the dose-limiting toxicity (DLT), evaluate the pharmacokinetic profile, and document any antitumor activity of NK012, a novel SN-38–incorporating micellar nanoparticle.

Experimental Design: Patients with solid tumors refractory to standard therapy, or for which no standard therapy is available, were enrolled. NK012 was administered as a 30-minute infusion every 3 weeks. The starting dose was 2 mg/m2 as SN-38 equivalent, and an accelerated titration schedule was used. Pharmacokinetic analysis was conducted in cycles 1 and 2.

Results: Twenty-four patients were enrolled in the study. No UGT1A1*28 homozygous patients were enrolled. Predominant toxicity was neutropenia. Nonhematologic toxicity, especially diarrhea, was mostly grade 1 or 2 during study treatments. Two of nine patients had DLT during cycle 1 at the 28 mg/m2 dose level. DLTs were mostly neutropenia or a related event. Polymer-bound SN-38 (NK012) and SN-38 released from NK012 were slowly eliminated from the plasma, with a terminal-phase half-life of approximately 140 and 210 hours, respectively. Systemic exposure to both polymer-bound SN-38 and SN-38 increased in proportion to the dose. A refractory esophageal cancer patient and a lung carcinoid tumor patient had an objective response and continued the study treatment for 5 and 12 months, respectively.

Conclusions: NK012 was well tolerated and showed antitumor activity including partial responses and several occurrences of prolonged stable disease across a variety of advanced refractory cancers. Phase II studies are ongoing. Clin Cancer Res; 16(20); 5058–66. ©2010 AACR.
No Evidence of Sex-Related Survival Disparities among Head and Neck Cancer Patients Receiving Similar Multidisciplinary Care: A Matched-Pair Analysis
Authors: Roberts Jess C. , Li Guojun , Reitzel Lorraine R. , Wei Qingyi , Sturgis Erich M.
Published: October 2010

Purpose: It is unknown whether there are survival disparities between men and women with squamous cell carcinoma of the head and neck (SCCHN), although some data suggest that men have worse outcomes. We conducted a matched-pair study that controlled for several potentially confounding prognostic variables to assess whether a survival advantage exists for female compared with male SCCHN patients receiving similar care.

Experimental Design: We selected 286 female patients and 286 matched male patients from within a prospective epidemiologic study on 1,654 patients with incident SCCHN evaluated and treated at a single large multidisciplinary cancer center. Matching variables included age (±10 y), race/ethnicity, smoking status (never versus ever), tumor site (oral cavity versus oropharynx versus larynx versus hypopharynx), tumor classification (T1-2 versus T3-4), nodal status (negative versus positive), and treatment (surgery, radiation therapy, surgery and radiation therapy, surgery and chemotherapy, chemoradiotherapy, or surgery and chemoradiotherapy).

Results: Matched-pair and log-rank analyses showed no significant differences between women and men in recurrence-free, disease-specific, or overall survival. When the analysis was restricted to individual sites (oral cavity, oropharynx, or larynx/hypopharynx), there was also no evidence of a disparity in survival associated with sex.

Conclusions: We conclude that there is no evidence to suggest that a survival advantage exists for women as compared with men with SCCHN receiving similar multidisciplinary directed care at a tertiary cancer center. Clin Cancer Res; 16(20); 5019–27. ©2010 AACR.