Transgalactosylation and hydrolytic activities of commercial preparations of β-galactosidase for the synthesis of prebiotic carbohydrates.

PubMed

Guerrero, Cecilia; Vera, Carlos; Conejeros, Raúl; Illanes, Andrés

2015-03-01

β-Galactosidases exhibit both hydrolytic and transgalactosylation activities; the former has been used traditionally for the production of delactosed milk and dairies, while the latter is being increasingly used for the synthesis of lactose-derived oligosaccharides: balance between both activities was highly dependent on the enzyme origin: β-galactosidases from Aspegillus oryzae and Bacillus circulans exhibited high transgalactosylation activity, while those from one from Kluyveromyces exhibited high hydrolytic activity but quite low transgalactosylation activity. Also the affinity for the donors (lactose or lactulose) and the acceptors (lactose, lactulose or fructose) of transgalactosylated galactose was dependent on the enzyme origin, as reflected by the Michaelis constants obtained in the synthesis of galacto-oligosaccharides, fructosyl-galacto-oligosaccharides and lactulose. Finally, the balance between transgalactosylation and hydrolytic activities of β-galactosidases could be tuned by changing the concentration of galactose donor. Copyright © 2014 Elsevier Inc. All rights reserved.

Selective Deletion of the Brain-Specific Isoform of Renin Causes Neurogenic Hypertension.

PubMed

Shinohara, Keisuke; Liu, Xuebo; Morgan, Donald A; Davis, Deborah R; Sequeira-Lopez, Maria Luisa S; Cassell, Martin D; Grobe, Justin L; Rahmouni, Kamal; Sigmund, Curt D

2016-12-01

The renin-angiotensin system (RAS) in the brain is a critical determinant of blood pressure, but the mechanisms regulating RAS activity in the brain remain unclear. Expression of brain renin (renin-b) occurs from an alternative promoter-first exon. The predicted translation product is a nonsecreted enzymatically active renin whose function is unknown. We generated a unique mouse model by selectively ablating the brain-specific isoform of renin (renin-b) while preserving the expression and function of the classical isoform expressed in the kidney (renin-a). Preservation of renal renin was confirmed by measurements of renin gene expression and immunohistochemistry. Surprisingly, renin-b-deficient mice exhibited hypertension, increased sympathetic nerve activity to the kidney and heart, and impaired baroreflex sensitivity. Whereas these mice displayed decreased circulating RAS activity, there was a paradoxical increase in brain RAS activity. Physiologically, renin-b-deficient mice exhibited an exaggerated depressor response to intracerebroventricular administration of losartan, captopril, or aliskiren. At the molecular level, renin-b-deficient mice exhibited increased expression of angiotensin-II type 1 receptor in the paraventricular nucleus, which correlated with an increased renal sympathetic nerve response to leptin, which was dependent on angiotensin-II type 1 receptor activity. Interestingly, despite an ablation of renin-b expression, expression of renin-a was significantly increased in rostral ventrolateral medulla. These data support a new paradigm for the genetic control of RAS activity in the brain by a coordinated regulation of the renin isoforms, with expression of renin-b tonically inhibiting expression of renin-a under baseline conditions. Impairment of this control mechanism causes neurogenic hypertension. © 2016 American Heart Association, Inc.

Effects of hydrolysis of milk glycerides on the antimutagenicity of a hexane extract of milk.

PubMed

Nadathur, S R; Zhou, L; Lowry, R R; Bakalinsky, A T

1998-03-01

Reconstituted nonfat dry milk was treated with different amounts of lipase from Pseudomonas fluorescens. Hexane extracts of treated milks were dissolved in dimethylsulfoxide and assayed for antimutagenicity using the Ames test (Salmonella typhimurium TA 100) against N-methyl, N'-nitro, N-nitrosoguanidine. Anti-N-methyl, N'-nitro, N-nitrosoguanidine activity increased significantly as the amount of added lipase increased. At the highest lipase concentration tested, activity increased 5-fold, suggesting that liberated fatty acids contributed to the increased antimutagenicity. The activities of mixtures of pure fatty acids on antimutagenesis were examined using the Ames test. At the lowest concentrations tested, mixtures of palmitic and stearic acids and mixtures of palmitic and isopalmitic acids exhibited greater activity than did the individual acids. At all doses tested, mixtures of the monoacylglycerides of palmitic and stearic acids exhibited the same activity as the individual components. Quantification of fatty acids in milk and yogurt by gas chromatography indicated a 2 to 20-fold greater content of free fatty acids in yogurt. The increase in free fatty acids may contribute to the increase in antimutagenicity of yogurt relative to that of milk.

Antidepressant-like effect of food-derived pyroglutamyl peptides in mice.

PubMed

Yamamoto, Yukako; Mizushige, Takafumi; Mori, Yukiha; Shimmura, Yuki; Fukutomi, Ruuta; Kanamoto, Ryuhei; Ohinata, Kousaku

2015-06-01

The N-terminal glutamine residue, exposed by enzymatic cleavage of precursor proteins, is known to be modified to a pyroglutamyl residue with a cyclic structure in not only endogenous but also food-derived peptides. We investigated the effects of wheat-derived pyroglutamyl peptides on emotional behaviors. Pyroglutamyl leucine (pyroGlu-Leu, pEL) and pyroglutamyl glutaminyl leucine (pyroGlu-Gln-Leu, pEQL) exhibited antidepressant-like activity in the tail suspension and forced swim tests in mice. pEQL exhibited more potent antidepressant-like activity than pEL after i.p. and i.c.v. administration. pEQL exhibited antidepressant-like activity at a lower dose than Gln-Gln-Leu, suggesting that pyroglutamyl peptide had more potent activity. To examine whether pyroglutamyl peptides increased hippocampus neurogenesis, associated with the effects of antidepressants, we measured 5-bromo-2'-deoxyuridine (BrdU) incorporation. pEL and pEQL increased BrdU-positive cells in the dentate gyrus of the hippocampus. Intriguingly, pEL did not increase hippocampal mRNA and protein expression of brain-derived neurotrophic factor (BDNF), which is a factor associated with both neuropoietic and antidepressive effects. Thus, pyroglutamyl peptides may enhance hippocampal neurogenesis via a pathway independent of BDNF. We also confirmed that pEL and pEQL were produced in the subtilisin digest of major wheat proteins, glutenin and gliadin, after heat treatment. pEL and pEQL are the first peptides derived from wheat proteins to be shown to exhibit an antidepressant-like activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

Aspartame-fed zebrafish exhibit acute deaths with swimming defects and saccharin-fed zebrafish have elevation of cholesteryl ester transfer protein activity in hypercholesterolemia.

PubMed

Kim, Jae-Yong; Seo, Juyi; Cho, Kyung-Hyun

2011-11-01

Although many artificial sweeteners (AS) have safety issues, the AS have been widely used in industry. To determine the physiologic effect of AS in the presence of hyperlipidemia, zebrafish were fed aspartame or saccharin with a high-cholesterol diet (HCD). After 12 days, 30% of zebrafish, which consumed aspartame and HCD, died with exhibiting swimming defects. The aspartame group had 65% survivability, while the control and saccharin groups had 100% survivability. Under HCD, the saccharin-fed groups had the highest increase in the serum cholesterol level (599 mg/dL). Aspartame-fed group showed a remarkable increase in serum glucose (up to 125 mg/dL), which was 58% greater than the increase in the HCD alone group. The saccharin and HCD groups had the highest cholesteryl ester transfer protein (CETP) activity (52% CE-transfer), while the HCD alone group had 42% CE-transfer. Histologic analysis revealed that the aspartame and HCD groups showed more infiltration of inflammatory cells in the brain and liver sections. Conclusively, under presence of hyperlipidemia, aspartame-fed zebrafish exhibited acute swimming defects with an increase in brain inflammation. Saccharin-fed zebrafish had an increased atherogenic serum lipid profile with elevation of CETP activity. Copyright © 2011 Elsevier Ltd. All rights reserved.

Synthetic (+)-antroquinonol exhibits dual actions against insulin resistance by triggering AMP kinase and inhibiting dipeptidyl peptidase IV activities

PubMed Central

Hsu, C Y; Sulake, R S; Huang, P-K; Shih, H-Y; Sie, H-W; Lai, Y-K; Chen, C; Weng, C F

2015-01-01

BACKGROUND AND PURPOSE The fungal product (+)-antroquinonol activates AMP kinase (AMPK) activity in cancer cell lines. The present study was conducted to examine whether chemically synthesized (+)-antroquinonol exhibited beneficial metabolic effects in insulin-resistant states by activating AMPK and inhibiting dipeptidyl peptidase IV (DPP IV) activity. EXPERIMENTAL APPROACH Effects of (+)-antroquinonol on DPP IV activity were measured with a DPPIV Assay Kit and effects on GLP-1-induced PKA were measured in AR42J cells. Translocation of the glucose transporter 4, GLUT4, induced either by insulin-dependent PI3K/AKT signalling or by insulin-independent AMPK activation, was assayed in differentiated myotubes. Glucose uptake and GLUT4 translocation were assayed in L6 myocytes. Mice with diet-induced obesity were used to assess effects of acute and chronic treatment with (+)-antroquinonol on glycaemic control in vivo. KEY RESULTS The results showed that of (+)-antroquinonol (100 μM ) inhibited the DPP IV activity as effectively as the clinically used inhibitor, sitagliptin. The phosphorylation of AMPK Thr172 in differentiated myotubes was significantly increased by (+)-antroquinonol. In cells simultaneously treated with S961 (insulin receptor antagonist), insulin and (+)-antroquinonol, the combination of (+)-antroquinonol plus insulin still increased both GLUT4 translocation and glucose uptake. Further, (+)-antroquinonol and sitagliptin reduced blood glucose, when given acutely or chronically to DIO mice. CONCLUSIONS AND IMPLICATIONS Chemically synthesized (+)-antroquinonol exhibits dual effects to ameliorate insulin resistance, by increasing AMPK activity and GLUT4 translocation, along with inhibiting DPP IV activity. PMID:24977411

Synthesis and Antibacterial Activities of Antibacterial Peptides with a Spiropyran Fluorescence Probe

PubMed Central

Chen, Lei; Zhu, Yu; Yang, Danling; Zou, Rongfeng; Wu, Junchen; Tian, He

2014-01-01

In this report, antibacterial peptides1-3 were prepared with a spiropyran fluorescence probe. The probe exhibits a change in fluorescence when isomerized from a colorless spiro-form (spiropyran, Sp) to a colored open-form (merocyanine, Mc) under different chemical environments, which can be used to study the mechanism of antimicrobial activity. Peptides 1-3 exhibit a marked decrease in antimicrobial activity with increasing alkyl chain length. This is likely due to the Sp-Mc isomers in different polar environments forming different aggregate sizes in TBS, as demonstrated by time-dependent dynamic light scattering (DLS). Moreover, peptides 1-3 exhibited low cytotoxicity and hemolytic activity. These probe-modified peptides may provide a novel approach to study the effect of structural changes on antibacterial activity, thus facilitating the design of new antimicrobial agents to combat bacterial infection. PMID:25358905

Inhibition of Excessive Monoamine Oxidase A/B Activity Protects Against Stress-induced Neuronal Death in Huntington Disease.

PubMed

Ooi, Jolene; Hayden, Michael R; Pouladi, Mahmoud A

2015-12-01

Monoamine oxidases (MAO) are important components of the homeostatic machinery that maintains the levels of monoamine neurotransmitters, including dopamine, in balance. Given the imbalance in dopamine levels observed in Huntington disease (HD), the aim of this study was to examine MAO activity in a mouse striatal cell model of HD and in human neural cells differentiated from control and HD patient-derived induced pluripotent stem cell (hiPSC) lines. We show that mouse striatal neural cells expressing mutant huntingtin (HTT) exhibit increased MAO expression and activity. We demonstrate using luciferase promoter assays that the increased MAO expression reflects enhanced epigenetic activation in striatal neural cells expressing mutant HTT. Using cellular stress paradigms, we further demonstrate that the increase in MAO activity in mutant striatal neural cells is accompanied by enhanced susceptibility to oxidative stress and impaired viability. Treatment of mutant striatal neural cells with MAO inhibitors ameliorated oxidative stress and improved cellular viability. Finally, we demonstrate that human HD neural cells exhibit increased MAO-A and MAO-B expression and activity. Altogether, this study demonstrates abnormal MAO expression and activity and suggests a potential use for MAO inhibitors in HD.

Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds.

PubMed

Ganesan, P; Kumar, Chandini S; Bhaskar, N

2008-05-01

In vitro antioxidant activities of three selected Indian red seaweeds - viz., Euchema kappaphycus, Gracilaria edulis and Acanthophora spicifera were evaluated. Total phenolic content and reducing power of crude methanol extract were determined. The antioxidant activities of total methanol extract and five different solvent fractions (viz., petroleum ether (PE), ethyl acetate (EA), dichloromethane (DCM), butanol (BuOH) and aqueous) were also evaluated. EA fraction of A. spicifera exhibited higher total antioxidant activity (32.01 mg ascorbic acid equivalent/g extract) among all the fractions. Higher phenolic content (16.26 mg gallic acid equivalent/g extract) was noticed in PE fraction of G. edulis. Reducing power of crude methanol extract increased with increasing concentration of the extract. Reducing power and hydroxyl radical scavenging activity of E. kappaphycus were higher compared to standard antioxidant (alpha-tocopherol). The total phenol content of all the seaweeds was significantly different (P<0.05). In vitro antioxidant activities of methanol extracts of all the three seaweeds exhibited dose dependency; and increased with increasing concentration of the extract.

Capacitance enhancement of polyaniline coated curved-graphene supercapacitors in a redox-active electrolyte

NASA Astrophysics Data System (ADS)

Chen, Wei; Rakhi, R. B.; Alshareef, H. N.

2013-05-01

We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50 000 cycles).We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50 000 cycles). Electronic supplementary information (ESI) available: Experimental section, supporting figures including SEM, TEM, XPS, BET, CV and CD curves and a summary table of capacitance. See DOI: 10.1039/c3nr00773a

Thyroid hormone regulation of Sirtuin 1 expression and implications to integrated responses in fasted mice.

PubMed

Cordeiro, Aline; de Souza, Luana Lopes; Oliveira, Lorraine Soares; Faustino, Larissa Costa; Santiago, Letícia Aragão; Bloise, Flavia Fonseca; Ortiga-Carvalho, Tania Maria; Almeida, Norma Aparecida Dos Santos; Pazos-Moura, Carmen Cabanelas

2013-02-01

Sirtuin 1 (SIRT1), a NAD(+)-dependent deacetylase, has been connected to beneficial effects elicited by calorie restriction. Physiological adaptation to starvation requires higher activity of SIRT1 and also the suppression of thyroid hormone (TH) action to achieve energy conservation. Here, we tested the hypothesis that those two events are correlated and that TH may be a regulator of SIRT1 expression. Forty-eight-hour fasting mice exhibited reduced serum TH and increased SIRT1 protein content in liver and brown adipose tissue (BAT), and physiological thyroxine replacement prevented or attenuated the increment of SIRT1 in liver and BAT of fasted mice. Hypothyroid mice exhibited increased liver SIRT1 protein, while hyperthyroid ones showed decreased SIRT1 in liver and BAT. In the liver, decreased protein is accompanied by reduced SIRT1 activity and no alteration in its mRNA. Hyperthyroid and hypothyroid mice exhibited increases and decreases in food intake and body weight gain respectively. Food-restricted hyperthyroid animals (pair-fed to euthyroid group) exhibited liver and BAT SIRT1 protein levels intermediary between euthyroid and hyperthyroid mice fed ad libitum. Mice with TH resistance at the liver presented increased hepatic SIRT1 protein and activity, with no alteration in Sirt1 mRNA. These results suggest that TH decreases SIRT1 protein, directly and indirectly, via food ingestion control and, in the liver, this reduction involves TRβ. The SIRT1 reduction induced by TH has important implication to integrated metabolic responses to fasting, as the increase in SIRT1 protein requires the fasting-associated suppression of TH serum levels.

Long-term hypoxia increases calcium affinity of BK channels in ovine fetal and adult cerebral artery smooth muscle

PubMed Central

Tao, Xiaoxiao; Lin, Mike T.; Thorington, Glyne U.; Wilson, Sean M.; Longo, Lawrence D.

2015-01-01

Acclimatization to high-altitude, long-term hypoxia (LTH) reportedly alters cerebral artery contraction-relaxation responses associated with changes in K+ channel activity. We hypothesized that to maintain oxygenation during LTH, basilar arteries (BA) in the ovine adult and near-term fetus would show increased large-conductance Ca2+ activated potassium (BK) channel activity. We measured BK channel activity, expression, and cell surface distribution by use of patch-clamp electrophysiology, flow cytometry, and confocal microscopy, respectively, in myocytes from normoxic control and LTH adult and near-term fetus BA. Electrophysiological data showed that BK channels in LTH myocytes exhibited 1) lowered Ca2+ set points, 2) left-shifted activation voltages, and 3) longer dwell times. BK channels in LTH myocytes also appeared to be more dephosphorylated. These differences collectively make LTH BK channels more sensitive to activation. Studies using flow cytometry showed that the LTH fetus exhibited increased BK β1 subunit surface expression. In addition, in both fetal groups confocal microscopy revealed increased BK channel clustering and colocalization to myocyte lipid rafts. We conclude that increased BK channel activity in LTH BA occurred in association with increased channel affinity for Ca2+ and left-shifted voltage activation. Increased cerebrovascular BK channel activity may be a mechanism by which LTH adult and near-term fetal sheep can acclimatize to long-term high altitude hypoxia. Our findings suggest that increasing BK channel activity in cerebral myocytes may be a therapeutic target to ameliorate the adverse effects of high altitude in adults or of intrauterine hypoxia in the fetus. PMID:25599571

The Arabidopsis cax1 Mutant Exhibits Impaired Ion Homeostasis, Development, and Hormonal Responses and Reveals Interplay among Vacuolar Transporters

PubMed Central

Cheng, Ning-Hui; Pittman, Jon K.; Barkla, Bronwyn J.; Shigaki, Toshiro; Hirschi, Kendal D.

2003-01-01

The Arabidopsis Ca2+/H+ transporter CAX1 (Cation Exchanger1) may be an important regulator of intracellular Ca2+ levels. Here, we describe the preliminary localization of CAX1 to the tonoplast and the molecular and biochemical characterization of cax1 mutants. We show that these mutants exhibit a 50% reduction in tonoplast Ca2+/H+ antiport activity, a 40% reduction in tonoplast V-type H+-translocating ATPase activity, a 36% increase in tonoplast Ca2+-ATPase activity, and increased expression of the putative vacuolar Ca2+/H+ antiporters CAX3 and CAX4. Enhanced growth was displayed by the cax1 lines under Mn2+ and Mg2+ stress conditions. The mutants exhibited altered plant development, perturbed hormone sensitivities, and altered expression of an auxin-regulated promoter-reporter gene fusion. We propose that CAX1 regulates myriad plant processes and discuss the observed phenotypes with regard to the compensatory alterations in other transporters. PMID:12566577

The Arabidopsis cax1 mutant exhibits impaired ion homeostasis, development, and hormonal responses and reveals interplay among vacuolar transporters.

PubMed

Cheng, Ning-Hui; Pittman, Jon K; Barkla, Bronwyn J; Shigaki, Toshiro; Hirschi, Kendal D

2003-02-01

The Arabidopsis Ca(2+)/H(+) transporter CAX1 (Cation Exchanger1) may be an important regulator of intracellular Ca(2+) levels. Here, we describe the preliminary localization of CAX1 to the tonoplast and the molecular and biochemical characterization of cax1 mutants. We show that these mutants exhibit a 50% reduction in tonoplast Ca(2+)/H(+) antiport activity, a 40% reduction in tonoplast V-type H(+)-translocating ATPase activity, a 36% increase in tonoplast Ca(2+)-ATPase activity, and increased expression of the putative vacuolar Ca(2+)/H(+) antiporters CAX3 and CAX4. Enhanced growth was displayed by the cax1 lines under Mn(2+) and Mg(2+) stress conditions. The mutants exhibited altered plant development, perturbed hormone sensitivities, and altered expression of an auxin-regulated promoter-reporter gene fusion. We propose that CAX1 regulates myriad plant processes and discuss the observed phenotypes with regard to the compensatory alterations in other transporters.

Antiviral activity of silver nanoparticle/chitosan composites against H1N1 influenza A virus

NASA Astrophysics Data System (ADS)

Mori, Yasutaka; Ono, Takeshi; Miyahira, Yasushi; Nguyen, Vinh Quang; Matsui, Takemi; Ishihara, Masayuki

2013-02-01

Silver nanoparticle (Ag NP)/chitosan (Ch) composites with antiviral activity against H1N1 influenza A virus were prepared. The Ag NP/Ch composites were obtained as yellow or brown floc-like powders following reaction at room temperature in aqueous medium. Ag NPs (3.5, 6.5, and 12.9 nm average diameters) were embedded into the chitosan matrix without aggregation or size alternation. The antiviral activity of the Ag NP/Ch composites was evaluated by comparing the TCID50 ratio of viral suspensions treated with the composites to untreated suspensions. For all sizes of Ag NPs tested, antiviral activity against H1N1 influenza A virus increased as the concentration of Ag NPs increased; chitosan alone exhibited no antiviral activity. Size dependence of the Ag NPs on antiviral activity was also observed: antiviral activity was generally stronger with smaller Ag NPs in the composites. These results indicate that Ag NP/Ch composites interacting with viruses exhibit antiviral activity.

Lead tolerance of water hyacinth (Eichhornia crassipes Mart. - Pontederiaceae) as defined by anatomical and physiological traits.

PubMed

Pereira, Fabricio J; Castro, Evaristo M de; Oliveira, Cynthia de; Pires, Marinês F; Pereira, Marcio P; Ramos, Silvio J; Faquin, Valdemar

2014-09-01

This study aimed at verifying the lead tolerance of water hyacinth and at looking at consequent anatomical and physiological modifications. Water hyacinth plants were grown on nutrient solutions with five different lead concentrations: 0.00, 0.50, 1.00, 2.00 and 4.00 mg L-1 by 20 days. Photosynthesis, transpiration, stomatal conductance and the Ci/Ca rate were measured at the end of 15 days of experiment. At the end of the experiment, the anatomical modifications in the roots and leaves, and the activity of antioxidant system enzymes, were evaluated. Photosynthetic and Ci/Ca rates were both increased under all lead treatments. Leaf anatomy did not exhibit any evidence of toxicity effects, but showed modifications of the stomata and in the thickness of the palisade and spongy parenchyma in the presence of lead. Likewise, root anatomy did not exhibit any toxicity effects, but the xylem and phloem exhibited favorable modifications as well as increased apoplastic barriers. All antioxidant system enzymes exhibited increased activity in the leaves, and some modifications in roots, in the presence of lead. It is likely, therefore, that water hyacinth tolerance to lead is related to anatomical and physiological modifications such as increased photosynthesis and enhanced anatomical capacity for CO2 assimilation and water conductance.

Age-related increase in brain activity during task-related and -negative networks and numerical inductive reasoning.

PubMed

Sun, Li; Liang, Peipeng; Jia, Xiuqin; Qi, Zhigang; Li, Kuncheng

2014-01-01

Recent neuroimaging studies have shown that elderly adults exhibit increased and decreased activation on various cognitive tasks, yet little is known about age-related changes in inductive reasoning. To investigate the neural basis for the aging effect on inductive reasoning, 15 young and 15 elderly subjects performed numerical inductive reasoning while in a magnetic resonance (MR) scanner. Functional magnetic resonance imaging (fMRI) analysis revealed that numerical inductive reasoning, relative to rest, yielded multiple frontal, temporal, parietal, and some subcortical area activations for both age groups. In addition, the younger participants showed significant regions of task-induced deactivation, while no deactivation occurred in the elderly adults. Direct group comparisons showed that elderly adults exhibited greater activity in regions of task-related activation and areas showing task-induced deactivation (TID) in the younger group. Our findings suggest an age-related deficiency in neural function and resource allocation during inductive reasoning.

Photobactericidal activity of methylene blue derivatives against vancomycin-resistant Enterococcus spp.

PubMed

Wainwright, M; Phoenix, D A; Gaskell, M; Marshall, B

1999-12-01

The toxicities and phototoxicities of methylene blue and its two methylated derivatives were measured against one standard and three vancomycin-resistant pathogenic strains of Enterococcus spp. Each of the compounds was bactericidal and the derivatives exhibited photobactericidal activity on illumination at a 'light' dose of 6.3 J/cm(2) against one or more of the strains. Increased bactericidal and photobactericidal activity in the methylated derivatives is thought to be due to their higher hydrophobicities allowing greater interaction with the bacterial cell wall. In addition, the derivatives exhibited higher inherent photosensitizing efficacies.

Moderate pressure massage elicits a parasympathetic nervous system response.

PubMed

Diego, Miguel A; Field, Tiffany

2009-01-01

Twenty healthy adults were randomly assigned to a moderate pressure or a light pressure massage therapy group, and EKGs were recorded during a 3-min baseline, during the 15-min massage period and during a 3-min postmassage period. EKG data were then used to derive the high frequency (HF), low frequency (LF) components of heart rate variability and the low to high frequency ratio (LF/HF) as noninvasive markers of autonomic nervous system activity. The participants who received the moderate pressure massage exhibited a parasympathetic nervous system response characterized by an increase in HF, suggesting increased vagal efferent activity and a decrease in the LF/HF ratio, suggesting a shift from sympathetic to parasympathetic activity that peaked during the first half of the massage period. On the other hand, those who received the light pressure massage exhibited a sympathetic nervous system response characterized by decreased HF and increased LF/HF.

Profiling Coping Strategies in Male and Female Rats: Potential neurobehavioral markers of increased resilience to depressive symptoms

PubMed Central

Kent, Molly; Bardi, Massimo; Hazelgrove, Ashley; Sewell, Kaitlyn; Kirk, Emily; Thompson, Brooke; Trexler, Kristen; Terhune-Cotter, Brennan; Lambert, Kelly

2018-01-01

Coping strategies have been associated with differential stress responsivity, perhaps providing a valuable neurobiological marker for susceptibility to the emergence of depressogenic symptoms or vulnerability to other anxiety-related disorders. Rats profiled with a flexible coping phenotype, for example, exhibit increased neurobiological markers of emotional regulation compared to active and passive copers (Bardi et al., 2012; Lambert et al., 2014). In the current study, responses of male and female rats to prediction errors in a spatial foraging task (dry land maze; DLM) were examined after animals were exposed to chronic unpredictable stress (CUS). Brains were processed following the DLM training/assessment for fos-activation patterns and several measures of neuroplasticity in relevant areas. Behavioral responses observed during both the CUS and DLM phases of testing suggested that males and females employ different means of gathering information such as increased ambulatory exploration in males and rear responses in females. Fecal samples collected during baseline and following CUS swim exposure revealed higher corticosterone (CORT) in active copers, whereas flexible copers had higher dehydroepiandrosterone (DHEA) and DHEA/CORT ratios, both indications of enhanced emotional regulation. Focusing on the neural analysis, flexible copers exhibited fewer fos-immunoreactive cells in the basolateral amygdala and a trend toward lower activation in the insula while encountering the prediction error associated with the DLM probe trial. Coping profiles also differentially influenced markers of neuroplasticity; specifically, flexible copers exhibited higher levels nestin-immunoreactivity (ir). Further, less hippocampal glucocorticoid receptor-ir was observed in the flexible copers than the active and passive copers. In sum, flexible coping rats exhibited evidence of emotional resilience as indicated by several neurobiological measures; however, despite increased rates of depression and related symptoms reported in human females, sex effects weren’t as pervasive as coping strategy profiles in the analysis of neurobiological markers employed in the current study. PMID:28755980

Refolding of β-Stranded Class I Chitinases of Hippophae rhamnoides Enhances the Antifreeze Activity during Cold Acclimation

PubMed Central

Gupta, Ravi; Deswal, Renu

2014-01-01

Class I chitinases hydrolyse the β-1,4-linkage of chitin and also acquire antifreeze activity in some of the overwintering plants during cold stress. Two chitinases, HrCHT1a of 31 kDa and HrCHT1b of 34 kDa, were purified from cold acclimated and non-acclimated seabuckthorn seedlings using chitin affinity chromatography. 2-D gels of HrCHT1a and HrCHT1b showed single spots with pIs 7.0 and 4.6 respectively. N-terminal sequence of HrCHT1b matched with the class I chitinase of rice and antifreeze proteins while HrCHT1a could not be sequenced as it was N-terminally blocked. Unlike previous reports, where antifreeze activity of chitinase was cold inducible, our results showed that antifreeze activity is constitutive property of class I chitinase as both HrCHT1a and HrCHT1b isolated even from non-acclimated seedlings, exhibited antifreeze activity. Interestingly, HrCHT1a and HrCHT1b purified from cold acclimated seedlings, exhibited 4 and 2 times higher antifreeze activities than those purified from non-acclimated seedlings, suggesting that antifreeze activity increased during cold acclimation. HrCHT1b exhibited 23–33% higher hydrolytic activity and 2–4 times lower antifreeze activity than HrCHT1a did. HrCHT1b was found to be a glycoprotein; however, its antifreeze activity was independent of glycosylation as even deglycosylated HrCHT1b exhibited antifreeze activity. Circular dichroism (CD) analysis showed that both these chitinases were rich in unusual β-stranded conformation (36–43%) and the content of β-strand increased (∼11%) during cold acclimation. Surprisingly, calcium decreased both the activities of HrCHT1b while in case of HrCHT1a, a decrease in the hydrolytic activity and enhancement in its antifreeze activity was observed. CD results showed that addition of calcium also increased the β-stranded conformation of HrCHT1a and HrCHT1b. This is the first report, which shows that antifreeze activity is constitutive property of class I chitinase and cold acclimation and calcium regulate these activities of chitinases by changing the secondary structure. PMID:24626216

Refolding of β-stranded class I chitinases of Hippophae rhamnoides enhances the antifreeze activity during cold acclimation.

PubMed

Gupta, Ravi; Deswal, Renu

2014-01-01

Class I chitinases hydrolyse the β-1,4-linkage of chitin and also acquire antifreeze activity in some of the overwintering plants during cold stress. Two chitinases, HrCHT1a of 31 kDa and HrCHT1b of 34 kDa, were purified from cold acclimated and non-acclimated seabuckthorn seedlings using chitin affinity chromatography. 2-D gels of HrCHT1a and HrCHT1b showed single spots with pIs 7.0 and 4.6 respectively. N-terminal sequence of HrCHT1b matched with the class I chitinase of rice and antifreeze proteins while HrCHT1a could not be sequenced as it was N-terminally blocked. Unlike previous reports, where antifreeze activity of chitinase was cold inducible, our results showed that antifreeze activity is constitutive property of class I chitinase as both HrCHT1a and HrCHT1b isolated even from non-acclimated seedlings, exhibited antifreeze activity. Interestingly, HrCHT1a and HrCHT1b purified from cold acclimated seedlings, exhibited 4 and 2 times higher antifreeze activities than those purified from non-acclimated seedlings, suggesting that antifreeze activity increased during cold acclimation. HrCHT1b exhibited 23-33% higher hydrolytic activity and 2-4 times lower antifreeze activity than HrCHT1a did. HrCHT1b was found to be a glycoprotein; however, its antifreeze activity was independent of glycosylation as even deglycosylated HrCHT1b exhibited antifreeze activity. Circular dichroism (CD) analysis showed that both these chitinases were rich in unusual β-stranded conformation (36-43%) and the content of β-strand increased (∼11%) during cold acclimation. Surprisingly, calcium decreased both the activities of HrCHT1b while in case of HrCHT1a, a decrease in the hydrolytic activity and enhancement in its antifreeze activity was observed. CD results showed that addition of calcium also increased the β-stranded conformation of HrCHT1a and HrCHT1b. This is the first report, which shows that antifreeze activity is constitutive property of class I chitinase and cold acclimation and calcium regulate these activities of chitinases by changing the secondary structure.

Impact of BDNF Val66Met and 5-HTTLPR polymorphism variants on neural substrates related to sadness and executive function.

PubMed

Wang, L; Ashley-Koch, A; Steffens, D C; Krishnan, K R R; Taylor, W D

2012-04-01

The brain-derived neurotrophic factor (BDNF) Val(66) Met allelic variation is linked to both the occurrence of mood disorders and antidepressant response. These findings are not universally observed, and the mechanism by which this variation results in increased risk for mood disorders is unclear. One possible explanation is an epistatic relationship with other neurotransmitter genes associated with depression risk, such as the serotonin-transporter-linked promotor region (5-HTTLPR). Further, it is unclear how the coexistence of the BDNF Met and 5-HTTLPR S variants affects the function of the affective and cognitive control systems. To address this question, we conducted a functional magnetic resonance imaging (fMRI) study in 38 older adults (20 healthy and 18 remitted from major depressive disorder). Subjects performed an emotional oddball task during the fMRI scan and provided blood samples for genotyping. Our analyses examined the relationship between genotypes and brain activation to sad distractors and attentional targets. We found that 5-HTTLPR S allele carriers exhibited stronger activation in the amygdala in response to sad distractors, whereas BDNF Met carriers exhibited increased activation to sad stimuli but decreased activation to attentional targets in the dorsolateral prefrontal and dorsomedial prefrontal cortices. In addition, subjects with both the S allele and Met allele genes exhibited increased activation to sad stimuli in the subgenual cingulate and posterior cingulate. Our results indicate that the Met allele alone or in combination with 5-HTTLPR S allele may increase reactivity to sad stimuli, which might represent a neural mechanism underlying increased depression vulnerability. © 2012 The Authors. Genes, Brain and Behavior © 2012 Blackwell Publishing Ltd and International Behavioural and Neural Genetics Society.

The effects of automated scatter feeders on captive grizzly bear activity budgets.

PubMed

Andrews, Nathan L P; Ha, James C

2014-01-01

Although captive bears are popular zoo attractions, they are known to exhibit high levels of repetitive behaviors (RBs). These behaviors have also made them particularly popular subjects for welfare research. To date, most research on ursid welfare has focused on various feeding methods that seek to increase time spent searching for, extracting, or consuming food. Prior research indicates an average of a 50% reduction in RBs when attempts are successful and, roughly, a 50% success rate across studies. This research focused on decreasing time spent in an RB while increasing the time spent active by increasing time spent searching for, extracting, and consuming food. The utility of timed, automated scatter feeders was examined for use with captive grizzly bears (Ursis arctos horribilis). Findings include a significant decrease in time spent in RB and a significant increase in time spent active while the feeders were in use. Further, the bears exhibited a wider range of behaviors and a greater use of their enclosure.

Increased Selectivity towards Cytoplasmic versus Mitochondrial Ribosome Confers Improved Efficiency of Synthetic Aminoglycosides in Fixing Damaged Genes: A Strategy for Treatment of Genetic Diseases Caused by Nonsense Mutations

PubMed Central

Kandasamy, Jeyakumar; Atia-Glikin, Dana; Shulman, Eli; Shapira, Katya; Shavit, Michal; Belakhov, Valery; Baasov, Timor

2012-01-01

Compelling evidence is now available that gentamicin and geneticin (G418) can induce mammalian ribosome to suppress disease-causing nonsense mutations and partially restore the expression of functional proteins. However, toxicity and relative lack of efficacy at subtoxic doses limit the use of gentamicin for suppression therapy. Although G418 exhibits strongest activity, it is very cytotoxic even at low doses. We describe here the first systematic development of the novel aminoglycoside (S)-11 exhibiting similar in vitro and ex vivo activity to that of G418, while its cell toxicity is significantly lower than those of gentamicin and G418. Using a series of biochemical assays, we provide proof of principle that antibacterial activity and toxicity of aminoglycosides can be dissected from their suppression activity. The data further indicate that the increased specificity towards cytoplasmic ribosome correlates with the increased activity, and that the decreased specificity towards mitochondrial ribosome confers to the lowered cytotoxicity. PMID:23148581

Increasing Student Physical Fitness through Increased Choice of Fitness Activities and Student Designed Fitness Activities for Ninth through Twelfth Graders in Physical Education Class

ERIC Educational Resources Information Center

Jacob, Margo A.

2011-01-01

This action research project report began when the teacher researcher determined that students exhibited physical fitness levels below that of the state and national norms, and also displayed negative attitudes about physical education. The purpose of this action research project was to increase physical fitness and fitness attitudes through…

Improving specific activity and thermostability of Escherichia coli phytase by structure-based rational design.

PubMed

Wu, Tzu-Hui; Chen, Chun-Chi; Cheng, Ya-Shan; Ko, Tzu-Ping; Lin, Cheng-Yen; Lai, Hui-Lin; Huang, Ting-Yung; Liu, Je-Ruei; Guo, Rey-Ting

2014-04-10

Escherichia coli phytase (EcAppA) which hydrolyzes phytate has been widely applied in the feed industry, but the need to improve the enzyme activity and thermostability remains. Here, we conduct rational design with two strategies to enhance the EcAppA performance. First, residues near the substrate binding pocket of EcAppA were modified according to the consensus sequence of two highly active Citrobacter phytases. One out of the eleven mutants, V89T, exhibited 17.5% increase in catalytic activity, which might be a result of stabilized protein folding. Second, the EcAppA glycosylation pattern was modified in accordance with the Citrobacter phytases. An N-glycosylation motif near the substrate binding site was disrupted to remove spatial hindrance for phytate entry and product departure. The de-glycosylated mutants showed 9.6% increase in specific activity. On the other hand, the EcAppA mutants that adopt N-glycosylation motifs from CbAppA showed improved thermostability that three mutants carrying single N-glycosylation motif exhibited 5.6-9.5% residual activity after treatment at 80°C (1.8% for wild type). Furthermore, the mutant carrying all three glycosylation motifs exhibited 27% residual activity. In conclusion, a successful rational design was performed to obtain several useful EcAppA mutants with better properties for further applications. Copyright © 2014 Elsevier B.V. All rights reserved.

Overexpression of a specific soybean GmGSTU4 isoenzyme improves diphenyl ether and chloroacetanilide herbicide tolerance of transgenic tobacco plants.

PubMed

Benekos, Kostantinos; Kissoudis, Christos; Nianiou-Obeidat, Irini; Labrou, Nikolaos; Madesis, Panagiotis; Kalamaki, Mary; Makris, Antonis; Tsaftaris, Athanasios

2010-10-01

Plant glutathione transferases (GSTs) superfamily consists of multifunctional enzymes and forms a major part of the plants herbicide detoxification enzyme network. The tau class GST isoenzyme GmGSTU4 from soybean, exhibits catalytic activity towards the diphenyl ether herbicide fluorodifen and is active as glutathione-dependent peroxidase (GPOX). Transgenic tobacco plants of Basmas cultivar were generated via Agrobacterium transformation. The aim was to evaluate in planta, GmGSTU4's role in detoxifying the diphenyl ether herbicides fluorodifen and oxyfluorfen and the chloroacetanilides alachlor and metolachlor. Transgenic tobacco plants were verified by PCR and Southern blot hybridization and expression of GmGSTU4 was determined by RT-PCR. Leaf extracts from transgenic plants showed moderate increase in GST activity towards CDNB and a significant increase towards fluorodifen and alachlor, and at the same time an increased GPOX activity towards cumene hydroperoxide. GmGSTU4 overexpressing plants when treated with 200 μM fluorodifen or oxyfluorfen exhibited reduced relative electrolyte leakage compared to wild type plants. Moreover all GmGSTU4 overexpressing lines exhibited significantly increased tolerance towards alachlor when grown in vitro at 7.5 mg/L alachlor compared to wild type plants. No significant increased tolerance was observed to metolachlor. These results confirm the contribution of this particular GmGSTU4 isoenzyme from soybean in the detoxification of fluorodifen and alachlor, and provide the basis towards the development of transgenic plants with improved phytoremediation capabilities for future use in environmental cleanup of herbicides. Copyright © 2010 Elsevier B.V. All rights reserved.

MK-801 increases locomotor activity in a context-dependent manner in zebrafish.

PubMed

Tran, Steven; Muraleetharan, Arrujyan; Fulcher, Niveen; Chatterjee, Diptendu; Gerlai, Robert

2016-01-01

Zebrafish have become a popular animal model for behavioral neuroscience with an increasing number of studies examining the effects of pharmacological compounds targeting the brain. Exposure to MK-801, a non-competitive N-methyl-d-aspartate receptor antagonist has been shown to increase locomotor activity in zebrafish. However, others have failed to replicate this finding as several contradicting studies report no changes in locomotor activity following exposure to similar doses. In the current study we reconcile these behavioral reports by demonstrating that zebrafish do not exhibit changes in locomotor activity during exposure to non-sedative doses of MK-801. Interestingly, zebrafish do exhibit significant increases in locomotion if pre-treated with MK-801 followed by subsequent testing in a novel environment, which suggests the effects of MK-801 are context-dependent. In addition, we examine the potential role of the dopaminergic system in mediating MK-801's locomotor stimulant effect by quantifying the levels of dopamine and its metabolite 3,4-dihydroxyphenylacetic acid (DOPAC) in the brains of zebrafish following a 30 min exposure to 10 μM of MK-801 (the dose found to induce the largest increase in locomotor activity). Our findings indicate that the MK-801-induced increase in locomotor activity is not accompanied by changes in whole-brain levels of dopamine or DOPAC. Overall, our results suggest that MK-801's context-dependent locomotor stimulant effect may be independent of whole-brain dopaminergic activation. Copyright © 2015 Elsevier B.V. All rights reserved.

The antioxidant activity of allylpyrocatechol is mediated via decreased generation of free radicals along with escalation of antioxidant mechanisms.

PubMed

Sarkar, Debjani; Kundu, Sunanda; De, Soumita; Hariharan, Chellaram; Saha, Piu; Manna, Alak; Chattopadhyay, Subrata; Chatterjee, Mitali

2013-03-01

Allylpyrocatechol (APC) is responsible for the antiinflammatory activity exhibited by the methanolic extract of leaves of Piper betle. As antiinflammatory compounds may display antioxidant properties and vice versa, we investigated the antioxidant effect of APC. APC effectively reduced phorbol-myristate-acetate-induced generation of reactive oxygen species and superoxide in murine peritoneal macrophages as well as inhibited Escherichia-coli-induced phagocytic activity of macrophages. Furthermore, pBluescript SK(+) plasmid DNA damage induced by addition of sodium ascorbate was attenuated by APC as it inhibited transformation of the supercoiled form to a relaxed form. In addition, APC increased the enzymatic (catalase) and nonenzymatic (GSH) antioxidant components of murine macrophages. Taken together, APC exhibited an antioxidant activity which was mediated both via decreased generation of free radicals along with increase in cellular antioxidants. Copyright © 2012 John Wiley & Sons, Ltd.

Saraca indica Bark Extract Shows In Vitro Antioxidant, Antibreast Cancer Activity and Does Not Exhibit Toxicological Effects

PubMed Central

Yadav, Navneet Kumar; Saini, Karan Singh; Hossain, Zakir; Omer, Ankur; Sharma, Chetan; Gayen, Jiaur R.; Singh, Poonam; Arya, K. R.; Singh, R. K.

2015-01-01

Medicinal plants are used as a complementary and alternative medicine in treatment of various diseases including cancer worldwide, because of their ease of accessibility and cost effectiveness. Multicomposed mixture of compounds present in a plant extract has synergistic activity, increases the therapeutic potential many folds, compensates toxicity, and increases bioavailability. Saraca indica (family Caesalpiniaceae) is one of the most ancient sacred plants with medicinal properties, exhibiting a number of pharmacological effects. Antioxidant, antibreast cancer activity and toxicological evaluation of Saraca indica bark extract (SIE) were carried out in the present study. The results of the study indicated that this herbal preparation has antioxidant and antibreast cancer activity. Toxicological studies suggest that SIE is safer to use and may have a potential to be used as complementary and alternative medicine for breast cancer therapy. PMID:25861411

Telmisartan enhances mitochondrial activity and alters cellular functions in human coronary artery endothelial cells via AMP-activated protein kinase pathway.

PubMed

Kurokawa, Hirofumi; Sugiyama, Seigo; Nozaki, Toshimitsu; Sugamura, Koichi; Toyama, Kensuke; Matsubara, Junichi; Fujisue, Koichiro; Ohba, Keisuke; Maeda, Hirofumi; Konishi, Masaaki; Akiyama, Eiichi; Sumida, Hitoshi; Izumiya, Yasuhiro; Yasuda, Osamu; Kim-Mitsuyama, Shokei; Ogawa, Hisao

2015-04-01

Mitochondrial dysfunction plays an important role in cellular senescence and impaired function of vascular endothelium, resulted in cardiovascular diseases. Telmisartan is a unique angiotensin II type I receptor blocker that has been shown to prevent cardiovascular events in high risk patients. AMP-activated protein kinase (AMPK) plays a critical role in mitochondrial biogenesis and endothelial function. This study assessed whether telmisartan enhances mitochondrial function and alters cellular functions via AMPK in human coronary artery endothelial cells (HCAECs). In cultured HCAECs, telmisartan significantly enhanced mitochondrial activity assessed by mitochondrial reductase activity and intracellular ATP production and increased the expression of mitochondria related genes. Telmisartan prevented cellular senescence and exhibited the anti-apoptotic and pro-angiogenic properties. The expression of genes related anti-oxidant and pro-angiogenic properties were increased by telmisartan. Telmisartan increased endothelial NO synthase and AMPK phosphorylation. Peroxisome proliferator-activated receptor gamma signaling was not involved in telmisartan-induced improvement of mitochondrial function. All of these effects were abolished by inhibition of AMPK. Telmisartan enhanced mitochondrial activity and exhibited anti-senescence effects and improving endothelial function through AMPK in HCAECs. Telmisartan could provide beneficial effects on vascular diseases via enhancement of mitochondrial activity and modulating endothelial function through AMPK activation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Weaker Seniors Exhibit Motor Cortex Hypoexcitability and Impairments in Voluntary Activation

PubMed Central

Taylor, Janet L.; Hong, S. Lee; Law, Timothy D.; Russ, David W.

2015-01-01

Background. Weakness predisposes seniors to a fourfold increase in functional limitations. The potential for age-related degradation in nervous system function to contribute to weakness and physical disability has garnered much interest of late. In this study, we tested the hypothesis that weaker seniors have impairments in voluntary (neural) activation and increased indices of GABAergic inhibition of the motor cortex, assessed using transcranial magnetic stimulation. Methods. Young adults (N = 46; 21.2±0.5 years) and seniors (N = 42; 70.7±0.9 years) had their wrist flexion strength quantified along with voluntary activation capacity (by comparing voluntary and electrically evoked forces). Single-pulse transcranial magnetic stimulation was used to measure motor-evoked potential amplitude and silent period duration during isometric contractions at 15% and 30% of maximum strength. Paired-pulse transcranial magnetic stimulation was used to measure intracortical facilitation and short-interval and long-interval intracortical inhibition. The primary analysis compared seniors to young adults. The secondary analysis compared stronger seniors (top two tertiles) to weaker seniors (bottom tertile) based on strength relative to body weight. Results. The most novel findings were that weaker seniors exhibited: (i) a 20% deficit in voluntary activation; (ii) ~20% smaller motor-evoked potentials during the 30% contraction task; and (iii) nearly twofold higher levels of long-interval intracortical inhibition under resting conditions. Conclusions. These findings indicate that weaker seniors exhibit significant impairments in voluntary activation, and that this impairment may be mechanistically associated with increased GABAergic inhibition of the motor cortex. PMID:25834195

Overexpression of the Type 1 Adenylyl Cyclase in the Forebrain Leads to Deficits of Behavioral Inhibition

PubMed Central

Cao, Hong; Saraf, Amit; Zweifel, Larry S.

2015-01-01

The type 1 adenylyl cyclase (AC1) is an activity-dependent, calcium-stimulated adenylyl cyclase expressed in the nervous system that is implicated in memory formation. We examined the locomotor activity, and impulsive and social behaviors of AC1+ mice, a transgenic mouse strain overexpressing AC1 in the forebrain. Here we report that AC1+ mice exhibit hyperactive behaviors and demonstrate increased impulsivity and reduced sociability. In contrast, AC1 and AC8 double knock-out mice are hypoactive, and exhibit increased sociability and reduced impulsivity. Interestingly, the hyperactivity of AC1+ mice can be corrected by valproate, a mood-stabilizing drug. These data indicate that increased expression of AC1 in the forebrain leads to deficits in behavioral inhibition. PMID:25568126

Behavioral and Neural Sustained Attention Deficits in Disruptive Mood Dysregulation Disorder and Attention-Deficit/Hyperactivity Disorder.

PubMed

Pagliaccio, David; Wiggins, Jillian Lee; Adleman, Nancy E; Curhan, Alexa; Zhang, Susan; Towbin, Kenneth E; Brotman, Melissa A; Pine, Daniel S; Leibenluft, Ellen

2017-05-01

Disruptive mood dysregulation disorder (DMDD), characterized by severe irritability, and attention-deficit/hyperactivity disorder (ADHD) are highly comorbid. This is the first study to characterize neural and behavioral similarities and differences in attentional functioning across these disorders. Twenty-seven healthy volunteers, 31 patients with DMDD, and 25 patients with ADHD (8 to 18 years old) completed a functional magnetic resonance imaging attention task. Group differences in intra-subject variability in reaction time (RT) were examined. The present functional magnetic resonance imaging analytic approach precisely quantified trial-wise associations between RT and brain activity. Group differences manifested in the relation between RT and brain activity (all regions: p < .01, F > 2.54, partial eta-squared [η p 2 ] > 0.06). Patients with DMDD showed specific alterations in the right paracentral lobule, superior parietal lobule, fusiform gyrus, and cerebellar culmen. In contrast, patients with DMDD and those with ADHD exhibited blunted compensatory increases in activity on long RT trials. In addition, youth with DMDD exhibited increased activity in the postcentral gyrus, medial frontal gyrus, and cerebellar tonsil and declive (all regions: p < .05, F > 2.46, η p 2 > 0.06). Groups in the imaging sample did not differ significantly in intra-subject variability in RT (F 2,79  = 2.664, p = .076, η p 2  = 0.063), although intra-subject variability in RT was significantly increased in youth with DMDD and ADHD when including those not meeting strict motion and accuracy criteria for imaging analysis (F 2,96  = 4.283, p = .017, η p 2  = 0.083). Patients with DMDD exhibited specific alterations in the relation between pre-stimulus brain activity and RT. Patients with DMDD and those with ADHD exhibited similar blunting of compensatory neural activity in frontal, parietal, and other regions. In addition, patients with DMDD showed increased RT variability compared with healthy youth. This work is the first to identify common and unique behavioral and neural signatures of DMDD and ADHD. Published by Elsevier Inc.

Immunopharmacological properties of noopept.

PubMed

Kovalenko, L P; Shipaeva, E V; Alekseeva, S V; Pronin, A V; Durnev, A D; Gudasheva, T A; Ostrovskaja, R U; Seredenin, S B

2007-07-01

Noopept, a peptide analog of piracetam, enhanced phagocytic activity of mouse peritoneal macrophages, stimulated humoral and cellular immune response to various antigens, and markedly increased spontaneous proliferative activity of splenocytes. In animals with secondary immune deficiency caused by cyclophosphamide, noopept exhibited immunocorrector properties.

Controlled preparation of Ag–Cu{sub 2}O nanocorncobs and their enhanced photocatalytic activity under visible light

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Siyuan; Zhang, Shengsen; College of Science, South China Agricultural University, Guangzhou 510642

Graphical abstract: The corncob-like Ag–Cu{sub 2}O nanostructure with suitably exposed Ag surface exhibited much higher photocatalytic activity than Ag@Cu{sub 2}O nanocables and Cu{sub 2}O nanowires. - Highlights: • Ag–Cu{sub 2}O nanocorncobs have been controllably prepared by a simple synthesis. • The possible formation mechanism of Ag–Cu{sub 2}O has been studied. • Ag–Cu{sub 2}O exhibits noticeable improved photocurrent compared with the pure Cu{sub 2}O NWs. • Ag–Cu{sub 2}O with suitably exposed Ag surface shows much higher photocatalytic activity. - Abstract: Novel corncob-like nano-heterostructured Ag–Cu{sub 2}O photocatalyst has been controllably prepared by adjusting the synthetic parameters, and the possible formation mechanism hasmore » been also studied. The photoelectrochemical and photocatalytic performances demonstrated that the as-prepared Ag–Cu{sub 2}O nanocorncobs exhibited higher photocatalytic activity than both pure Cu{sub 2}O nanowires and cable-like Ag@Cu{sub 2}O nano-composites. It was concluded that Ag–Cu{sub 2}O nanocorncobs with suitably exposed Ag surface not only effectively inhibit the recombination of electron–hole pairs but also suitably increase the active sites of electronic conduction, and thus increasing the photocatalytic activity under visible light irradiation.« less

Age-related increase in brain activity during task-related and -negative networks and numerical inductive reasoning

PubMed Central

Sun, Li; Liang, Peipeng; Jia, Xiuqin; Qi, Zhigang; Li, Kuncheng

2014-01-01

Objective: Recent neuroimaging studies have shown that elderly adults exhibit increased and decreased activation on various cognitive tasks, yet little is known about age-related changes in inductive reasoning. Methods: To investigate the neural basis for the aging effect on inductive reasoning, 15 young and 15 elderly subjects performed numerical inductive reasoning while in a magnetic resonance (MR) scanner. Results: Functional magnetic resonance imaging (fMRI) analysis revealed that numerical inductive reasoning, relative to rest, yielded multiple frontal, temporal, parietal, and some subcortical area activations for both age groups. In addition, the younger participants showed significant regions of task-induced deactivation, while no deactivation occurred in the elderly adults. Direct group comparisons showed that elderly adults exhibited greater activity in regions of task-related activation and areas showing task-induced deactivation (TID) in the younger group. Conclusions: Our findings suggest an age-related deficiency in neural function and resource allocation during inductive reasoning. PMID:25337240

Maintaining physical activity during refeeding improves body composition, intestinal hyperpermeability and behavior in anorectic mice

PubMed Central

Achamrah, Najate; Nobis, Séverine; Breton, Jonathan; Jésus, Pierre; Belmonte, Liliana; Maurer, Brigitte; Legrand, Romain; Bôle-Feysot, Christine; Rego, Jean Luc do; Goichon, Alexis; Rego, Jean Claude do; Déchelotte, Pierre; Fetissov, Sergueï O; Claeyssens, Sophie; Coëffier, Moïse

2016-01-01

A role of gut-brain axis emerges in the pathophysiology of anorexia nervosa and maintaining adapted physical activity during refeeding remains discussed. We aimed to assess gastrointestinal protein metabolism and investigate the contribution of physical activity during refeeding in C57BL/6 mice with activity-based anorexia (ABA). ABA mice exhibited lower body weight and food intake with increase of lean mass/fat mass ratio and fat oxidation. Colonic permeability was increased in ABA. Ad libitum food access was then restored and ABA group was divided into two subgroups, with access to running wheel (ABA-PA) or not (ABA-NPA). After refeeding, fat free mass was completely restored only in ABA-PA. Colonic permeability was enhanced in ABA-NPA. Finally, muscle kynurenine conversion into kynurenic acid was lower in ABA-NPA who also exhibited altered behavior. Maintaining physical activity during refeeding may thus limit colonic hyperpermeability and improve behavior in anorectic mice. PMID:26906060

Effect of obesity on acute hemostatic responses to live-fire training drills.

PubMed

Smith, Denise L; Horn, Gavin P; Petruzzello, Steven J; Freund, Gregory G; Woods, Jeffrey A; Cook, Marc D; Goldstein, Eric; Fernhall, Bo

2014-12-01

The objective of this study was to evaluate the impact of obesity and firefighting activities on coagulation and fibrinolytic activity in relatively young, apparently healthy firefighters. Firefighters performed simulated firefighting activities for 18 minutes in a live-fire training structure. Blood samples were obtained at baseline, before firefighting, and within a few minutes of completing the activity. Nearly all markers of coagulation and fibrinolytic activity increased immediately after firefighting with an overall shift toward a procoagulatory profile. Obese firefighters exhibited lower levels of tissue plasminogen activator activity (0.98 vs 0.63 IU/ml) and higher levels of plasminogen activator inhibitor-1 activity (2.2 vs 4.5 ng/ml) at baseline compared with normal-weight firefighters, suggesting that fibrinolytic activity was lower in obese firefighters. There were few interactions between body mass index and firefighting activity, thus our findings suggest that obese firefighters did not exhibit a greater procoagulatory response to live firefighting compared with normal-weight firefighters. Acute live firefighting produced increases in both fibrinolytic and coagulatory responses; although obesity was associated with a reduced fibrinolytic profile at baseline, the changes produced by acute firefighting were similar in obese and nonobese firefighters. Copyright © 2014 Elsevier Inc. All rights reserved.

Activity budgets and the relationship between feeding and stereotypic behaviors in Asian elephants (Elephas maximus) in a Zoo.

PubMed

Rees, Paul A

2009-03-01

Activity budgets were studied in eight Asian elephants (Elephas maximus) at Chester Zoo (UK) for 35 days, between January and November 1999. Recordings were made between 10:00 and 16:00 hr (with most behavior frequencies calculated between 10:00 and 14:00 hr). The elephants exhibited variation in activity depending on their age, sex, the time of day and the time of year. Only the five adult cows exhibited stereotypic behavior, with frequencies ranging from 3.9 to 29.4% of all observations. These elephants exhibited individual, diurnal and seasonal variation in stereotypic behavior. This has implications for studies that use short sampling periods and may make comparisons of data collected at different times of the day or year invalid. The six adult elephants spent 27.4-41.4% of the time feeding (between 10:00 and 14:00 hr), 22.9-42.0% standing still, 6.1-19.2% walking and 3.9-9.6% dusting. The hypothesis that the frequency of stereotypic behavior in adult cow elephants was negatively correlated with the frequency of feeding behavior was tested and was found to be true. Stereotypic behavior increased in frequency toward the end of the day-while waiting to return to the elephant house for food--and elephants spent more time stereotyping during the winter months than during the summer months. Elephants were inactive (i.e. exhibited behaviors other than locomotion) for between 70.1 and 93.9% of the time. Creating more opportunities for elephants to exhibit foraging behavior and the introduction of greater unpredictability into management regimes, especially feeding times, may reduce the frequency of stereotypic behavior and increase general activity levels.

Halophilic Bacteria of Lunsu Produce an Array of Industrially Important Enzymes with Salt Tolerant Activity.

PubMed

Gupta, Sonika; Sharma, Parul; Dev, Kamal; Sourirajan, Anuradha

2016-01-01

The halophilic bacterial isolates SS1, SS2, SS3, SS5, and SS8 were characterized for production of industrially important enzymes like amylase, protease, lipase, and glutaminase. Halophilic bacterial isolates SS1 and SS3 exhibited salt dependent extracellular amylase and protease activities. Both the halophilic isolates SS1 and SS3 exhibited maximum amylase and protease activities in the presence of 1.5 and 1.0 M NaCl, respectively, with the optimum pH 8 and temperature 40°C. SS2 showed maximum extracellular protease and lipase activities in the presence of 0.75 M NaCl, at optimum pH of 7, and temperature 37°C. The glutaminase activity of SS3 increased with increase in concentration of NaCl up to 2.5 M. The optimum pH and temperature for L-glutaminase activity of SS3 was 8 and 40°C, respectively. The combined hydrolytic activities of these halophilic bacterial isolates can be used for bioconversion of organic materials to useful products.

Halophilic Bacteria of Lunsu Produce an Array of Industrially Important Enzymes with Salt Tolerant Activity

PubMed Central

Gupta, Sonika; Sharma, Parul; Dev, Kamal; Sourirajan, Anuradha

2016-01-01

The halophilic bacterial isolates SS1, SS2, SS3, SS5, and SS8 were characterized for production of industrially important enzymes like amylase, protease, lipase, and glutaminase. Halophilic bacterial isolates SS1 and SS3 exhibited salt dependent extracellular amylase and protease activities. Both the halophilic isolates SS1 and SS3 exhibited maximum amylase and protease activities in the presence of 1.5 and 1.0 M NaCl, respectively, with the optimum pH 8 and temperature 40°C. SS2 showed maximum extracellular protease and lipase activities in the presence of 0.75 M NaCl, at optimum pH of 7, and temperature 37°C. The glutaminase activity of SS3 increased with increase in concentration of NaCl up to 2.5 M. The optimum pH and temperature for L-glutaminase activity of SS3 was 8 and 40°C, respectively. The combined hydrolytic activities of these halophilic bacterial isolates can be used for bioconversion of organic materials to useful products. PMID:26885394

A systematic review and meta-analysis of lower limb neuromuscular alterations associated with knee osteoarthritis during level walking.

PubMed

Mills, Kathryn; Hunt, Michael A; Leigh, Ryan; Ferber, Reed

2013-08-01

Neuromuscular alterations are increasingly reported in individuals with knee osteoarthritis (KOA) during level walking. We aimed to determine which neuromuscular alterations are consistent in KOA individuals and how these may be influenced by osteoarthritis severity, varus alignment and/or joint laxity. Electronic databases were searched up to July 2012. Cross-sectional observational studies comparing lower-limb neuromuscular activity in individuals with KOA, healthy controls or with different KOA cohorts were included. Two reviewers assessed methodological quality. Effect sizes were used to quantify the magnitude of observed differences. Where studies were homogenous, effect sizes were pooled using a fixed-effects model. Fourteen studies examining neuromuscular alterations in indices of co-contraction, muscle amplitude and muscle activity duration were included. Data pooling revealed that moderate KOA individuals exhibit increased co-contraction of lateral knee muscles (ES 0.64 [0.3 to 0.97]) and moderately increased rectus femoris (ES 0.73 [0.23 to 1.22]), vastus lateralis (ES 0.77 [0.27 to 1.27]) and biceps femoris (ES 1.18 [0.67 to 1.7]) mean amplitude. Non-pooled data indicated prolonged activity of these muscles. Increased medial knee neuromuscular activity was prevalent for those exhibiting varus alignment and medial knee joint laxity. Interpretation Individuals with KOA exhibited increased co-contraction, amplitude and duration of lateral knee muscles regardless of disease severity, limb alignment or medial joint laxity. Individuals with severe disease, varus alignment and medial joint laxity demonstrate up-regulation of medial knee muscles. Future research investigating the efficacy of neuromuscular rehabilitation programs should consider the effect of simultaneous up-regulation of medial and lateral knee muscles on disease progression. © 2013.

Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region

USGS Publications Warehouse

Kassotis, Christopher D.; Tillitt, Donald E.; Davis, J. Wade; Hormann, Anette M.; Nagel, Susan C.

2014-01-01

The rapid rise in natural gas extraction using hydraulic fracturing increases the potential for contamination of surface and ground water from chemicals used throughout the process. Hundreds of products containing more than 750 chemicals and components are potentially used throughout the extraction process, including more than 100 known or suspected endocrine-disrupting chemicals. We hypothesized thataselected subset of chemicalsusedin natural gas drilling operationsandalso surface and ground water samples collected in a drilling-dense region of Garfield County, Colorado, would exhibit estrogen and androgen receptor activities. Water samples were collected, solid-phase extracted, and measured for estrogen and androgen receptor activities using reporter gene assays in human cell lines. Of the 39 unique water samples, 89%, 41%, 12%, and 46% exhibited estrogenic, antiestrogenic, androgenic, and antiandrogenic activities, respectively. Testing of a subset of natural gas drilling chemicals revealed novel antiestrogenic, novel antiandrogenic, and limited estrogenic activities. The Colorado River, the drainage basin for this region, exhibited moderate levels of estrogenic, antiestrogenic, and antiandrogenic activities, suggesting that higher localized activity at sites with known natural gas–related spills surrounding the river might be contributing to the multiple receptor activities observed in this water source. The majority of water samples collected from sites in a drilling-dense region of Colorado exhibited more estrogenic, antiestrogenic, or antiandrogenic activities than reference sites with limited nearby drilling operations. Our data suggest that natural gas drilling operationsmayresult in elevated endocrine-disrupting chemical activity in surface and ground water.

Transgenic alfalfa (Medicago sativa) with increased sucrose phosphate synthase activity shows enhanced growth when grown under N2-fixing conditions.

PubMed

Gebril, Sayed; Seger, Mark; Villanueva, Fabiola Muro; Ortega, Jose Luis; Bagga, Suman; Sengupta-Gopalan, Champa

2015-10-01

Overexpression of SPS in alfalfa is accompanied by early flowering, increased plant growth and an increase in elemental N and protein content when grown under N2-fixing conditions. Sucrose phosphate synthase (SPS; EC 2.3.1.14) is the key enzyme in the synthesis of sucrose in plants. The outcome of overexpression of SPS in different plants using transgenic approaches has been quite varied, but the general consensus is that increased SPS activity is associated with the production of new sinks and increased sink strength. In legumes, the root nodule is a strong C sink and in this study our objective was to see how increasing SPS activity in a legume would affect nodule number and function. Here we have transformed alfalfa (Medicago sativa, cv. Regen SY), with a maize SPS gene driven by the constitutive CaMV35S promoter. Our results showed that overexpression of SPS in alfalfa, is accompanied by an increase in nodule number and mass and an overall increase in nitrogenase activity at the whole plant level. The nodules exhibited an increase in the level of key enzymes contributing to N assimilation including glutamine synthetase and asparagine synthetase. Moreover, the stems of the transformants showed higher level of the transport amino acids, Asx, indicating increased export of N from the nodules. The transformants exhibited a dramatic increase in growth both of the shoots and roots, and earlier flowering time, leading to increased yields. Moreover, the transformants showed an increase in elemental N and protein content. The overall conclusion is that increased SPS activity improves the N status and plant performance, suggesting that the availability of more C in the form of sucrose enhances N acquisition and assimilation in the nodules.

A Fractal Dimension Survey of Active Region Complexity

NASA Technical Reports Server (NTRS)

McAteer, R. T. James; Gallagher, Peter; Ireland, Jack

2005-01-01

A new approach to quantifying the magnetic complexity of active regions using a fractal dimension measure is presented. This fully-automated approach uses full disc MDI magnetograms of active regions from a large data set (2742 days of the SoHO mission; 9342 active regions) to compare the calculated fractal dimension to both Mount Wilson classification and flare rate. The main Mount Wilson classes exhibit no distinct fractal dimension distribution, suggesting a self-similar nature of all active regions. Solar flare productivity exhibits an increase in both the frequency and GOES X-ray magnitude of flares from regions with higher fractal dimensions. Specifically a lower threshold fractal dimension of 1.2 and 1.25 exists as a necessary, but not sufficient, requirement for an active region to produce M- and X-class flares respectively .

Overweight female rats selectively breed for low aerobic capacity exhibit increased myocardial fibrosis and diastolic dysfunction

PubMed Central

Johnson, Megan S.; Ma, Lixin; Pulakat, Lakshmi; Mugerfeld, Irina; Hayden, Melvin R.; Garro, Mona; Knight, William; Britton, Steven L.; Koch, Lauren G.; Sowers, James R.

2012-01-01

The statistical association between endurance exercise capacity and cardiovascular disease suggests that impaired aerobic metabolism underlies the cardiovascular disease risk in men and women. To explore this connection, we applied divergent artificial selection in rats to develop low-capacity runner (LCR) and high-capacity runner (HCR) rats and found that disease risks segregated strongly with low running capacity. Here, we tested if inborn low aerobic capacity promotes differential sex-related cardiovascular effects. Compared with HCR males (HCR-M), LCR males (LCR-M) were overweight by 34% and had heavier retroperitoneal, epididymal, and omental fat pads; LCR females (LCR-F) were 20% heavier than HCR females (HCR-F), and their retroperitoneal, but not perireproductive or omental, fat pads were heavier as well. Unlike HCR-M, blood pressure was elevated in LCR-M, and this was accompanied by left ventricular (LV) hypertrophy. Like HCR-F, LCR-F exhibited normal blood pressure and LV weight as well as increased spontaneous cage activity compared with males. Despite normal blood pressures, LCR-F exhibited increased myocardial interstitial fibrosis and diastolic dysfunction, as indicated by increased LV stiffness, a decrease in the initial filling rate, and an increase in diastolic relaxation time. Although females exhibited increased arterial stiffness, ejection fraction was normal. Increased interstitial fibrosis and diastolic dysfunction in LCR-F was accompanied by the lowest protein levels of phosphorylated AMP-actived protein kinase [phospho-AMPK (Thr172)] and silent information regulator 1. Thus, the combination of risk factors, including female sex, intrinsic low aerobic capacity, and overweightness, promote myocardial stiffness/fibrosis sufficient to induce diastolic dysfunction in the absence of hypertension and LV hypertrophy. PMID:22345570

Enhancement of the anti-inflammatory activity of temporin-1Tl-derived antimicrobial peptides by tryptophan, arginine and lysine substitutions.

PubMed

Rajasekaran, Ganesan; Kamalakannan, Radhakrishnan; Shin, Song Yub

2015-10-01

Temporin-1Tl (TL) is a 13-residue frog antimicrobial peptide (AMP) exhibiting potent antimicrobial and anti-inflammatory activity. To develop novel AMP with improved anti-inflammatory activity and antimicrobial selectivity, we designed and synthesized a series of TL analogs by substituting Trp, Arg and Lys at selected positions. Except for Escherichia coli and Staphylococcus epidermidis, all TL analogs exhibited retained or increased antimicrobial activity against seven bacterial strains including three methicillin-resistant Staphylococcus aureus strains compared with TL. TL-1 and TL-4 showed a little increase in antimicrobial selectivity, while TL-2 and TL-3 displayed slightly decreased antimicrobial selectivity because of their about twofold increased hemolytic activity. All TL analogs demonstrated greatly increased anti-inflammatory activity, evident by their higher inhibition of the production tumor necrosis factor-α (TNF-α) and nitric oxide and the mRNA expression of inducible nitric oxide synthase and TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells, compared with TL. Taken together, the peptide anti-inflammatory activity is as follows: TL-2 ≈ TL-3 ≈ TL-4 > TL-1 > TL. In addition, LPS binding ability of the peptides corresponded with their anti-inflammatory activity. These results apparently suggest that the anti-inflammatory activity of TL analogs is associated with the direct binding ability between these peptides and LPS. Collectively, our designed TL analogs possess improved anti-inflammatory activity and retain antimicrobial activity without a significant increase in hemolysis. Therefore, it is evident that our TL analogs constitute promising candidates for the development of peptide therapeutics for gram-negative bacterial infection. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.

S-nitrosocaptopril nanoparticles as nitric oxide-liberating and transnitrosylating anti-infective technology.

PubMed

Mordorski, Breanne; Pelgrift, Robert; Adler, Brandon; Krausz, Aimee; da Costa Neto, Alexandre Batista; Liang, Hongying; Gunther, Leslie; Clendaniel, Alicea; Harper, Stacey; Friedman, Joel M; Nosanchuk, Joshua D; Nacharaju, Parimala; Friedman, Adam J

2015-02-01

Nitric oxide (NO), an essential agent of the innate immune system, exhibits multi-mechanistic antimicrobial activity. Previously, NO-releasing nanoparticles (NO-np) demonstrated increased antimicrobial activity when combined with glutathione (GSH) due to formation of S-nitrosoglutathione (GSNO), a transnitrosylating agent. To capitalize on this finding, we incorporated the thiol-containing ACE-inhibitor, captopril, with NO-np to form SNO-CAP-np, nanoparticles that both release NO and form S-nitrosocaptopril. In the presence of GSH, SNO-CAP-np demonstrated increased transnitrosylation activity compared to NO-np, as exhibited by increased GSNO formation. Escherichia coli and methicillin-resistant Staphylococcus aureus were highly susceptible to SNO-CAP-np in a dose-dependent fashion, with E. coli being most susceptible, and SNO-CAP-np were nontoxic in zebrafish embryos at translatable concentrations. Given SNO-CAP-np's increased transnitrosylation activity and increased E. coli susceptibility compared to NO-np, transnitrosylation rather than free NO is likely responsible for overcoming E. coli's resistance mechanisms and ultimately killing the pathogen. This team of authors incorporated the thiol-containing ACE-inhibitor, captopril, into a nitric oxide releasing nanoparticle system, generating nanoparticles that both release NO and form S-nitrosocaptopril, with pronounced toxic effects on MRSA and E. coli in the presented model system. Copyright © 2015 Elsevier Inc. All rights reserved.

Motivating the Reluctant Reader.

ERIC Educational Resources Information Center

Buzard, Barbara; Jarosz, Diane; Lato, Kelly; Zimmermann, Lori

This report describes a program for increasing student reading motivation through the use of cooperative learning activities, differentiating reading instruction, and active reading strategies. The students of the targeted second, fourth, sixth and eighth grade classes exhibited a reluctance to read that interfered with academic growth. Probable…

Chemical Composition and Biological Activities of Mono- and Heterofloral Bee Pollen of Different Geographical Origins

PubMed Central

Araújo, Jucilene Silva; Chambó, Emerson Dechechi; Costa, Maria Angélica Pereira de Carvalho; Cavalcante da Silva, Samira Maria Peixoto; Lopes de Carvalho, Carlos Alfredo; M. Estevinho, Leticia

2017-01-01

Recent research shows variations in pollen chemical constituents and, consequently, in their therapeutic properties. Mono and multifloral bee pollen extracts were investigated for antioxidant and enzyme inhibitory activity properties, phenolic compounds and fatty acid composition. Generally, Eucalyptus spp. and multifloral extracts exhibited potent inhibitory activity against α-amylase, acetylcholinesterase, tyrosinase, lipoxygenase, lipase and hyaluronidase. On the other hand, Miconia spp. demonstrated higher antihemolytic activity. Cocos nucifera and Miconia spp. extracts exhibited important antioxidant properties in the different assays (ABTS, DPPH, β-carotene/linoleic acid and reducing power). Moreover, these extracts had greater amounts of total phenols and flavonoids in comparison to others. The increase in antioxidant activity (decrease in EC50 values) was accompanied by an increase in the amount of total phenols in the extracts. The pollen extracts contained linoleic acid and α-linolenic acid as major fatty acids, followed by palmitic acid, and oleic acid. In this study, differences were observed in both chemical constituents and biological activities of the samples related to the geographical and botanical origin of bee pollen. PMID:28448467

Bringing Hands-on Activities and Real Scientists to Students: Bishop Museum's X-treme Science Exhibit, Holoholo Science Program, and Planned Science Learning Center

NASA Astrophysics Data System (ADS)

Hills, D. J.; Fullerton, K.; Hoddick, C.; Ali, N.; Mosher, M. K.

2002-12-01

Bishop Museum developed the "X-treme Science: Exploring Oceans, Volcanoes, and Outer Space" museum exhibit in conjunction with NASA as part of their goal to increase educational outreach. A key element of the exhibit was the inclusion of real scientists describing what they do, and fostering the interaction between scientists and students. Highlights of the exhibit were interviews with local (Hawaii-based) scientists involved in current ocean, volcano, and space research. These interviews were based on questions that students provided, and were available during the exhibit at interactive kiosks. Lesson plans were developed by local teachers and scientists, and provided online to enhance the exhibit. However, one limitation of the museum exhibit was that not all students in the state could visit, or spend enough time with it. To serve more remote schools, and to provide for additional enrichment for those who did attend, the education department at Bishop Museum developed a traveling program with the X-treme Science exhibit as the basis. The Holoholo (Hawaiian for "fun outing") Science program brings a scientist into the classroom with a hands-on scientific inquiry activity. The activity is usually a simplified version of a problem that the scientist actually deals with. The students explore the activity, reach conclusions, and discuss their results. They are then given the opportunity to question the scientist about the activity and about what the scientist does. This allows students to understand that science is not something mystical, but rather something attainable. A key element of Holoholo remains the active participation of real-life scientists in the experience. The scientists who have participated in the program have had overwhelmingly positive experiences. Bishop Museum is developing a science learning center, with the objective of meeting local and national science standards using inquiry based science. The unifying theme of all three of these projects is involving students with active scientists who are accessible to them. AGU scientists are vital to realizing this goal.

How active was solar cycle 22?

NASA Technical Reports Server (NTRS)

Hoegy, W. R.; Pesnell, W. D.; Woods, T. N.; Rottman, G. J.

1993-01-01

Solar EUV observations from the Langmuir probe on Pioneer Venus Orbiter suggest that at EUV wavelengths solar cycle 22 was more active than solar cycle 21. The Langmuir probe, acting as a photodiode, measured the integrated solar EUV flux over a 13 1/2 year period from January 1979 to June 1992, the longest continuous solar EUV measurement. The Ipe EUV flux correlated very well with the SME measurement of L-alpha during the lifetime of SME and with the UARS SOLSTICE L-alpha from October 1991 to June 1992 when the Ipe measurement ceased. Starting with the peak of solar cycle 21, there was good general agreement of Ipe EUV with the 10.7 cm, Ca K, and He 10830 solar indices, until the onset of solar cycle 22. From 1989 to the start of 1992, the 10.7 cm flux exhibited a broad maximum consisting of two peaks of nearly equal magnitude, whereas Ipe EUV exhibited a strong increase during this time period making the second peak significantly higher than the first. The only solar index that exhibits the same increase in solar activity as Ipe EUV and L-alpha during the cycle 22 peak is the total magnetic flux. The case for high activity during this peak is also supported by the presence of very high solar flare intensity.

Occurrence and potential causes of androgenic activities in source and drinking water in China.

PubMed

Hu, Xinxin; Shi, Wei; Wei, Si; Zhang, Xiaowei; Feng, Jianfang; Hu, Guanjiu; Chen, Sulan; Giesy, John P; Yu, Hongxia

2013-09-17

The increased incidences of disorders of male reproductive tract as well as testicular and prostate cancers have been attributed to androgenic pollutants in the environment. Drinking water is one pathway of exposure through which humans can be exposed. In this study, both potencies of androgen receptor (AR) agonists and antagonists were determined in organic extracts of raw source water as well as finished water from waterworks, tap water, boiled water, and poured boiled water in eastern China. Ten of 13 samples of source water exhibited detectable AR antagonistic potencies with AR antagonist equivalents (Ant-AR-EQs) ranging from <15.3 (detection limit) to 140 μg flutamide/L. However, no AR agonistic activity was detected in any source water. All finished water from waterworks, tap water, boiled water, and poured boiled water exhibited neither AR agonistic nor antagonistic activity. Although potential risks are posed by source water, water treatment processes effectively removed AR antagonists. Boiling and pouring of water further removed these pollutants. Phthalate esters (PAEs) including diisobutyl phthalate (DIBP) and dibutyl phthalate (DBP) were identified as major contributors to AR antagonistic potencies in source waters. Metabolites of PAEs exhibited no AR antagonistic activity and did not increase potencies of PAEs when they coexist.

Synthesis of molecular imprinted polymer modified TiO{sub 2} nanotube array electrode and their photoelectrocatalytic activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu Na; Chen Shuo; Wang Hongtao

2008-10-15

A tetracycline hydrochloride (TC) molecularly imprinted polymer (MIP) modified TiO{sub 2} nanotube array electrode was prepared via surface molecular imprinting. Its surface was structured with surface voids and the nanotubes were open at top end with an average diameter of approximately 50 nm. The MIP-modified TiO{sub 2} nanotube array with anatase phase was identified by XRD and a distinguishable red shift in the absorption spectrum was observed. The MIP-modified electrode also exhibited a high adsorption capacity for TC due to its high surface area providing imprinted sites. Photocurrent was generated on the MIP-modified photoanode using the simulated solar spectrum andmore » increased with the increase of positive bias potential. Under simulated solar light irradiation, the MIP-modified TiO{sub 2} nanotube array electrode exhibited enhanced photoelectrocatalytic (PEC) activity with the apparent first-order rate constant being 1.2-fold of that with TiO{sub 2} nanotube array electrode. The effect of the thickness of the MIP layer on the PEC activity was also evaluated. - Graphical abstract: A tetracycline hydrochloride molecularly imprinted polymer modified TiO{sub 2} nanotube array electrode was prepared via surface molecular imprinting. It showed improved response to simulated solar light and higher adsorption capability for tetracycline hydrochloride, thereby exhibiting increased PEC activity under simulated solar light irradiation. The apparent first-order rate constant was 1.2-fold of that on TiO{sub 2} nanotube array electrode.« less

Design and activity of novel lactoferrampin analogues against O157:H7 enterohemorrhagic Escherichia coli.

PubMed

Cruz, Jenniffer; Ortiz, Claudia; Guzmán, Fanny; Cárdenas, Constanza; Fernandez-Lafuente, Roberto; Torres, Rodrigo

2014-04-01

Lactoferrampin 265-284 (LFampin 265-284) is a peptide consisting of residues 265-284 of N1-domain of bovine Lactoferrin (LF). This peptide has several cationic groups in the C-terminal lobe, exhibiting an antibacterial activity against a wide range of microorganisms. However, LFampin 265-284 exhibits low antimicrobial activity against the O157:H7 enterohaemorrhagic Escherichia coli (EHEC O157:H7) when compared with Lactoferrin chimera and Lactoferricin. Here, we have designed three analogues of LFampin 265-284 based on the distribution of cationic groups, hydrophobicity, size, and sequence. Analogues were synthesized by solid phase chemistry using Fmoc methodology obtaining peptides with 95% purity. All peptides maintain the ability to adopt helical conformations (checked by circular dichroism spectra and molecular simulations). Some of these analogues exhibited a significant increase in antimicrobial activity by counting colony forming units against EHEC O157:H7 compared to native LFampin 265-284, with MIC of 10 and 40 µM for 264G-D265K and 264G-D265K/S272R, respectively. The incorporation of a GKLI sequence in the N-terminal lobe increased dramatically its antibacterial activity, an effect which has been attributed to the addition of cationic groups in the N-terminal side that may stabilize the helical conformation of the new designed peptides. Copyright © 2013 Wiley Periodicals, Inc.

Estimates of increased black carbon emissions from electrostatic precipitators during powdered activated carbon injection for mercury emissions control.

PubMed

Clack, Herek L

2012-07-03

The behavior of mercury sorbents within electrostatic precipitators (ESPs) is not well-understood, despite a decade or more of full-scale testing. Recent laboratory results suggest that powdered activated carbon exhibits somewhat different collection behavior than fly ash in an ESP and particulate filters located at the outlet of ESPs have shown evidence of powdered activated carbon penetration during full-scale tests of sorbent injection for mercury emissions control. The present analysis considers a range of assumed differential ESP collection efficiencies for powdered activated carbon as compared to fly ash. Estimated emission rates of submicrometer powdered activated carbon are compared to estimated emission rates of particulate carbon on submicrometer fly ash, each corresponding to its respective collection efficiency. To the extent that any emitted powdered activated carbon exhibits size and optical characteristics similar to black carbon, such emissions could effectively constitute an increase in black carbon emissions from coal-based stationary power generation. The results reveal that even for the low injection rates associated with chemically impregnated carbons, submicrometer particulate carbon emissions can easily double if the submicrometer fraction of the native fly ash has a low carbon content. Increasing sorbent injection rates, larger collection efficiency differentials as compared to fly ash, and decreasing sorbent particle size all lead to increases in the estimated submicrometer particulate carbon emissions.

dSir2 mediates the increased spontaneous physical activity in flies on calorie restriction.

PubMed

Parashar, Vijay; Rogina, Blanka

2009-06-22

Calorie restriction (CR) is the most effective way to increase life span and delay the onset of age-related symptoms in animals. We have previously reported that CR affects a variety of physiological phenotypes in flies and results in dramatic behavioral, physical and demographic changes. Here we show effects of low and high calorie levels on the spontaneous physical activity of flies. Wild type flies maintained on a low calorie diet exhibit higher spontaneous activity compared to flies on higher calorie diets. This increase is dependent on the presence of Sir2 since a low calorie diet does not increase the activity of dSir2 null flies. Similarly, increasing dSir2 activity by feeding flies resveratrol, a CR mimetic, increases spontaneous physical activity of flies on high caloric food. In Drosophila, spontaneous physical activity therefore closely mimics life span in its dependence on Sir2.

Oxidative stress plays a role in high glucose-induced activation of pancreatic stellate cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryu, Gyeong Ryul; Lee, Esder; Chun, Hyun-Ji

Highlights: •High glucose increased production of reactive oxygen species in cultured pancreatic stellate cells. •High glucose facilitated the activation of these cells. •Antioxidant treatment attenuated high glucose-induced activation of these cells. -- Abstract: The activation of pancreatic stellate cells (PSCs) is thought to be a potential mechanism underlying islet fibrosis, which may contribute to progressive β-cell failure in type 2 diabetes. Recently, we demonstrated that antioxidants reduced islet fibrosis in an animal model of type 2 diabetes. However, there is no in vitro study demonstrating that high glucose itself can induce oxidative stress in PSCs. Thus, PSCs were isolated andmore » cultured from Sprague Dawley rats, and treated with high glucose for 72 h. High glucose increased the production of reactive oxygen species. When treated with high glucose, freshly isolated PSCs exhibited myofibroblastic transformation. During early culture (passage 1), PSCs treated with high glucose contained an increased number of α-smooth muscle actin-positive cells. During late culture (passages 2–5), PSCs treated with high glucose exhibited increases in cell proliferation, the expression of fibronectin and connective tissue growth factor, release of interleukin-6, transforming growth factor-β and collagen, and cell migration. Finally, the treatment of PSCs with high glucose and antioxidants attenuated these changes. In conclusion, we demonstrated that high glucose increased oxidative stress in primary rat PSCs, thereby facilitating the activation of these cells, while antioxidant treatment attenuated high glucose-induced PSC activation.« less

Ethylene Regulates Energy-Dependent Non-Photochemical Quenching in Arabidopsis through Repression of the Xanthophyll Cycle.

PubMed

Chen, Zhong; Gallie, Daniel R

2015-01-01

Energy-dependent (qE) non-photochemical quenching (NPQ) thermally dissipates excess absorbed light energy as a protective mechanism to prevent the over reduction of photosystem II and the generation of reactive oxygen species (ROS). The xanthophyll cycle, induced when the level of absorbed light energy exceeds the capacity of photochemistry, contributes to qE. In this work, we show that ethylene regulates the xanthophyll cycle in Arabidopsis. Analysis of eto1-1, exhibiting increased ethylene production, and ctr1-3, exhibiting constitutive ethylene response, revealed defects in NPQ resulting from impaired de-epoxidation of violaxanthin by violaxanthin de-epoxidase (VDE) encoded by NPQ1. Elevated ethylene signaling reduced the level of active VDE through decreased NPQ1 promoter activity and impaired VDE activation resulting from a lower transthylakoid membrane pH gradient. Increasing the concentration of CO2 partially corrected the ethylene-mediated defects in NPQ and photosynthesis, indicating that changes in ethylene signaling affect stromal CO2 solubility. Increasing VDE expression in eto1-1 and ctr1-3 restored light-activated de-epoxidation and qE, reduced superoxide production and reduced photoinhibition. Restoring VDE activity significantly reversed the small growth phenotype of eto1-1 and ctr1-3 without altering ethylene production or ethylene responses. Our results demonstrate that ethylene increases ROS production and photosensitivity in response to high light and the associated reduced plant stature is partially reversed by increasing VDE activity.

Ethylene Regulates Energy-Dependent Non-Photochemical Quenching in Arabidopsis through Repression of the Xanthophyll Cycle

PubMed Central

Chen, Zhong; Gallie, Daniel R.

2015-01-01

Energy-dependent (qE) non-photochemical quenching (NPQ) thermally dissipates excess absorbed light energy as a protective mechanism to prevent the over reduction of photosystem II and the generation of reactive oxygen species (ROS). The xanthophyll cycle, induced when the level of absorbed light energy exceeds the capacity of photochemistry, contributes to qE. In this work, we show that ethylene regulates the xanthophyll cycle in Arabidopsis. Analysis of eto1-1, exhibiting increased ethylene production, and ctr1-3, exhibiting constitutive ethylene response, revealed defects in NPQ resulting from impaired de-epoxidation of violaxanthin by violaxanthin de-epoxidase (VDE) encoded by NPQ1. Elevated ethylene signaling reduced the level of active VDE through decreased NPQ1 promoter activity and impaired VDE activation resulting from a lower transthylakoid membrane pH gradient. Increasing the concentration of CO2 partially corrected the ethylene-mediated defects in NPQ and photosynthesis, indicating that changes in ethylene signaling affect stromal CO2 solubility. Increasing VDE expression in eto1-1 and ctr1-3 restored light-activated de-epoxidation and qE, reduced superoxide production and reduced photoinhibition. Restoring VDE activity significantly reversed the small growth phenotype of eto1-1 and ctr1-3 without altering ethylene production or ethylene responses. Our results demonstrate that ethylene increases ROS production and photosensitivity in response to high light and the associated reduced plant stature is partially reversed by increasing VDE activity. PMID:26630486

Synthesis and Anticancer Mechanism Investigation of Dual Hsp27 and Tubulin Inhibitors

PubMed Central

Zhong, Bo; Chennamaneni, Snigdha; Lama, Rati; Yi, Xin; Geldenhuys, Werner J.; Pink, John J.; Dowlati, Afshin; Xu, Yan; Zhou, Aimin; Su, Bin

2013-01-01

Heat shock protein 27 (Hsp27) is a chaperone protein, and its expression is increased in response to various stress stimuli including anticancer chemotherapy, which allows the cells to survive and causes drug resistance. We previously identified lead compounds that bound to Hsp27 and tubulin via proteomic approaches. Systematic ligand based optimization in the current study significantly increased the cell growth inhibition and apoptosis inducing activities of the compounds. Compared to the lead compounds, one of the new derivatives exhibited much better potency to inhibit tubulin polymerization but a decreased activity to inhibit Hsp27 chaperone function, suggesting that the structural modification dissected the dual targeting effects of the compound. The most potent compounds 20 and 22 exhibited strong cell proliferation inhibitory activities at subnanomolar concentration against 60 human cancer cell lines conducted by Developmental Therapeutic Program at the National Cancer Institute and represented promising candidates for anticancer drug development. PMID:23767669

Antioxidant capacities and total phenolic contents increase with gamma irradiation in two types of Malaysian honey.

PubMed

Hussein, Saba Zuhair; Yusoff, Kamaruddin Mohd; Makpol, Suzana; Yusof, Yasmin Anum Mohd

2011-07-27

Two types of monofloral Malaysian honey (Gelam and Nenas) were analyzed to determine their antioxidant activities and total phenolic and flavonoid contents, with and without gamma irradiation. Our results showed that both types of honey can scavenge free radicals and exhibit high antioxidant-reducing power; however, Gelam honey exhibited higher antioxidant activity (p < 0.05) than Nenas honey, which is in good correlation (r = 0.9899) with its phenolic contents. Interestingly, we also noted that both irradiated honeys have higher antioxidant activities and total phenolic and flavonoid contents compared to nonirradiated honeys by Folin-Ciocalteu and UV-spectrophotometry methods, respectively. However, HPLC analysis for phenolic compounds showed insignificant increase between irradiated and nonirradiated honeys. The phenolic compounds such as: caffeic acid, chlorogenic acid, ellagic acid, p- coumaric acid, quercetin and hesperetin as indicated by HPLC method were found to be higher in Gelam honey versus Nenas honey. In conclusion, irradiation of honey causes enhanced antioxidant activities and flavonoid compounds.

Efflux Pumps Are Involved in the Defense of Gram-Negative Bacteria against the Natural Products Isobavachalcone and Diospyrone ▿

PubMed Central

Kuete, Victor; Ngameni, Bathélémy; Tangmouo, Jean G.; Bolla, Jean-Michel; Alibert-Franco, Sandrine; Ngadjui, Bonaventure T.; Pagès, Jean-Marie

2010-01-01

The activities of two naturally occurring compounds, isobavachalcone and diospyrone, against documented strains and multidrug-resistant (MDR) Gram-negative bacterial isolates were evaluated. The results indicated that the two compounds exhibited intrinsic antibacterial activity against several Gram-negative bacteria, and their activities were significantly improved in the presence of an efflux pump inhibitor (MIC values decreased to below 10 μg/ml). In addition, the activities of isobavachalcone and diospyrone against various strains exhibiting deletions of the major efflux pump components (AcrAB, TolC) were significantly increased. The overall results indicate that isobavachalcone and diospyrone could be candidates for the development of new drugs against MDR strains and that their use in combination with efflux pump inhibitors reinforces their activity. PMID:20160051

Transformation of Lactuca sativa L. with rol C gene results in increased antioxidant potential and enhanced analgesic, anti-inflammatory and antidepressant activities in vivo.

PubMed

Ismail, Hammad; Dilshad, Erum; Waheed, Mohammad Tahir; Sajid, Moniba; Kayani, Waqas Khan; Mirza, Bushra

2016-12-01

Lettuce is an important edible crop which possesses various medicinal properties. In this study Lactuca sativa L. (cv Grand Rapids) was transformed by Agrobacterium-mediated transformation with rol C gene. Transgene integration and expression was confirmed through PCR and semiquantitative RT-PCR. The transformed extracts were evaluated for their in vitro antioxidant and in vivo analgesic, anti-inflammatory and antidepressant activities in rats. The transformed plants showed 53-98 % increase in total phenolic and 45-58 % increase in total flavonoid contents compared with untransformed plants. Results of total reducing power and total antioxidant capacity exhibited 90-118 and 61-75 % increase in transformed plants, respectively. In contrast to control, DPPH, lipid peroxidation and DNA protection assay showed up to 37, 20 and 50 % enhancement in transformed plants, respectively. The extracts showed similar but significant enhancement behavior in hot plate analgesic and carrageenan-induced hind paw edema test. The transformed extracts showed 72.1 and 78.5 % increase for analgesic and anti-inflammatory activities, respectively. The transformants of rol C gene exhibited prominent antidepressant activity with 64-73 % increase compared with untransformed plants. In conclusion, the present work suggests that transformation with rol C gene can be used to generate lettuce with enhanced medicinally important properties, such as antioxidant, analgesic, anti-inflammatory and antidepressant potential.

[Antiradical activity and resistance of flaxseed oil enriched with the antioxidants to oxidative changes].

PubMed

Guseva, D A; Prozorovskaia, N N; Rusina, I F; Ipatova, O M

2008-01-01

Using the chemiluminescence technique, the effective concentration of antioxidants (AO) and its reactivity towards peroxyl radicals (constant k7) have been measured for the oil "Ubicato-flax" (biological active supplement) and flaxseed oil, enriched with Aronia melanocarpa extract. Ubicato-flax exhibited the highest antiradical activity but it was less resistant to oxidative changes as compared with flaxseed oil + extract. Ubicato oil produced on basis of natural AO exhibited higher antiradical activity in comparison with Ubicato oil produced on basis of the chemical synthetic AO. Aronia extract added to flaxseed oil caused marked inhibition of the increase in the peroxide value. Ubicato-flax may serve as a source of AO for not more than 6 months.

Alcohol Attenuates Load-related Activation During a Working Memory Task: Relation to Level of Response to Alcohol

PubMed Central

Paulus, Martin P.; Tapert, Susan F.; Pulido, Carmen; Schuckit, Marc A.

2008-01-01

Background A low level of response to alcohol is a major risk factor for the development of alcohol dependence, but neural correlates of this marker are unclear. Method Ten healthy volunteers were classified by median split on level of response to alcohol and underwent 2 sessions of functional magnetic resonance imaging following ingestion of a moderate dose of alcohol and a placebo. The blood oxygen level–dependent activation to an event-related visual working memory test was examined. Results The subjects exhibited longer response latencies and more errors as a function of increasing working memory load and showed a load-dependent increase in activation in dorsolateral prefrontal cortex, posterior parietal cortex, and visual cortex. Alcohol did not affect performance (errors or response latency), but attenuated the working memory load–dependent activation in the dorsolateral prefrontal cortex. During the placebo condition, individuals with a low level of response to alcohol showed greater activation in dorsolateral prefrontal cortex and posterior parietal cortex than those with a high level of response to alcohol. During the alcohol condition, groups showed similar attenuation of load-dependent brain activation in these regions. Conclusion Low-level responders relative to high-level responders exhibited an increased working memory load–dependent activation in dorsolateral prefrontal cortex and posterior parietal cortex when not exposed to alcohol. This increase in brain response was attenuated in low-level responders after ingesting a moderate dose of alcohol. PMID:16899039

The physiological and biochemical effects of salicylic acid on sunflowers (Helianthus annuus) exposed to flurochloridone.

PubMed

Kaya, Armagan; Yigit, Emel

2014-08-01

In this study, we comparatively evaluated the effects of the flurochloridone as well as flurochloridone and exogenously applied salicylic acid (SA) on Helianthus annuus L. to find out herbicide-induced toxicity reducing influence of SA. We examined and compared the physiological and biochemical effects of different concentrations of flurochloridone (11, 32 and 72 mM) in both the SA pre-treated and non-treated plants. The plants treated with flurochloridone exhibited reduced total chlorophyll, carotenoid, and relative water content compared to the control group, whereas the plants that were pre-treated with SA exhibited relatively higher values for the same physiological parameters. In the SA non-treated plants, the superoxide dismutase, glutathione reductase and glutathione S-transferase activities were increased in the treatment groups compared to the control group. In the treatment groups, these enzyme activities were decreased in the SA-pre-treated plants compared to the non-treated plants. Ascorbate peroxidase and catalase activities decreased in the flurochloridone-treated plants compared to the control plants. The ascorbate peroxidase activity increased in the control groups but decreased in the treatment groups in the SA pre-treated plants compared to the non-treated plants. However, SA treatment decreased the activity of catalase in the control and treatment groups compared to the plants that were not treated with SA. Flurochloridone treatment increased the malondialdehyde content in the treated groups compared to the control groups, whereas SA-pretreatment decreased malondialdehyde content compared to plants that were not treated with SA. Flurochloridone treatment increased endogenous SA content compared to the control. Although the residual levels of herbicide in the plants increased proportionately with increasing herbicide concentrations, the SA-pre-treated plants exhibited reduced residual herbicide levels compared to the plants that were not treated with SA. These results indicate that the flurochloridone induces various physiological and biochemical responses in non-target plants and that treatment with exogenous SA can increase stress resistance by altering these responses. Copyright © 2014 Elsevier Inc. All rights reserved.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skordas, E. S., E-mail: eskordas@phys.uoa.gr

By applying Detrended Fluctuation Analysis (DFA) to the time series of the geomagnetic data recorded at three measuring stations in Japan, Rong et al. in 2012 recently reported that anomalous magnetic field variations were identified well before the occurrence of the disastrous Tohoku M{sub w}9.0 earthquake that occurred on 11 March 2011 in Japan exhibiting increased “non-uniform” scaling behavior. Here, we provide an explanation for the appearance of this increase of “non-uniform” scaling on the following grounds: These magnetic field variations are the ones that accompany the electric field variations termed Seismic Electric Signals (SES) activity which have been repeatedlymore » reported that precede major earthquakes. DFA as well as multifractal DFA reveal that the latter electric field variations exhibit scaling behavior as shown by analyzing SES activities observed before major earthquakes in Greece. Hence, when these variations are superimposed on a background of pseudosinusoidal trend, their long range correlation properties—quantified by DFA—are affected resulting in an increase of the “non-uniform” scaling behavior. The same is expected to hold for the former magnetic field variations. This explanation is strengthened by recent findings showing that the fluctuations of the order parameter of seismicity exhibited an unprecedented minimum almost two months before the Tohoku earthquake occurrence which is characteristic for an almost simultaneous emission of Seismic Electric Signals activity.« less

Threonine deaminase from extremely halophilic bacteria - Cooperative substrate kinetics and salt dependence.

NASA Technical Reports Server (NTRS)

Lieberman, M. M.; Lanyi, J. K.

1972-01-01

The effect of salt on the activity, stability, and allosteric properties of catabolic threonine deaminase from Halobacterium cutirubrum was studied. The enzyme exhibits sigmoidal kinetics with the substrate, threonine. The Hill slope is 1.55 at pH 10. The enzyme is activated by ADP at low substrate concentrations. In the presence of this effector, sigmoidal kinetics are no longer observed. At pH 10, in the absence of ADP, enzyme activity increases with increasing NaCl concentration from 0 to 4 M.

76 FR 25240 - Clothianidin; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-04

... neurotoxicity were exhibited in both rats (decreased arousal, motor activity and locomotor activity) and mice... (decreased body weight gains and absolute thymus weights in pups, delayed sexual maturation and an increase.../day FQPA SF = 1x day.. based on decreased body weight gains and delayed sexual maturation, decreased...

Osteocytes mediate the anabolic actions of canonical Wnt/β-catenin signaling in bone

PubMed Central

Tu, Xiaolin; Delgado-Calle, Jesus; Condon, Keith W.; Maycas, Marta; Zhang, Huajia; Carlesso, Nadia; Taketo, Makoto M.; Burr, David B.; Plotkin, Lilian I.; Bellido, Teresita

2015-01-01

Osteocytes, >90% of the cells in bone, lie embedded within the mineralized matrix and coordinate osteoclast and osteoblast activity on bone surfaces by mechanisms still unclear. Bone anabolic stimuli activate Wnt signaling, and human mutations of components along this pathway underscore its crucial role in bone accrual and maintenance. However, the cell responsible for orchestrating Wnt anabolic actions has remained elusive. We show herein that activation of canonical Wnt signaling exclusively in osteocytes [dominant active (da)βcatOt mice] induces bone anabolism and triggers Notch signaling without affecting survival. These features contrast with those of mice expressing the same daß-catenin in osteoblasts, which exhibit decreased resorption and perinatal death from leukemia. daßcatOt mice exhibit increased bone mineral density in the axial and appendicular skeleton, and marked increase in bone volume in cancellous/trabecular and cortical compartments compared with littermate controls. daßcatOt mice display increased resorption and formation markers, high number of osteoclasts and osteoblasts in cancellous and cortical bone, increased bone matrix production, and markedly elevated periosteal bone formation rate. Wnt and Notch signaling target genes, osteoblast and osteocyte markers, and proosteoclastogenic and antiosteoclastogenic cytokines are elevated in bones of daßcatOt mice. Further, the increase in RANKL depends on Sost/sclerostin. Thus, activation of osteocytic β-catenin signaling increases both osteoclasts and osteoblasts, leading to bone gain, and is sufficient to activate the Notch pathway. These findings demonstrate disparate outcomes of β-catenin activation in osteocytes versus osteoblasts and identify osteocytes as central target cells of the anabolic actions of canonical Wnt/β-catenin signaling in bone. PMID:25605937

Molecular Docking and Site-directed Mutagenesis of a Bacillus thuringiensis Chitinase to Improve Chitinolytic, Synergistic Lepidopteran-larvicidal and Nematicidal Activities

PubMed Central

Ni, Hong; Zeng, Siquan; Qin, Xu; Sun, Xiaowen; Zhang, Shan; Zhao, Xiuyun; Yu, Ziniu; Li, Lin

2015-01-01

Bacterial chitinases are useful in the biocontrol of agriculturally important pests and fungal pathogens. However, the utility of naturally occurring bacterial chitinases is often limited by their low enzyme activity. In this study, we constructed mutants of a Bacillus thuringiensis chitinase with enhanced activity based on homology modeling, molecular docking, and the site-directed mutagenesis of target residues to modify spatial positions, steric hindrances, or hydrophilicity/hydrophobicity. We first identified a gene from B. thuringiensis YBT-9602 that encodes a chitinase (Chi9602) belonging to glycosyl hydrolase family 18 with conserved substrate-binding and substrate-catalytic motifs. We constructed a structural model of a truncated version of Chi9602 (Chi960235-459) containing the substrate-binding domain using the homologous 1ITX protein of Bacillus circulans as the template. We performed molecular docking analysis of Chi960235-459 using di-N-acetyl-D-glucosamine as the ligand. We then selected 10 residues of interest from the docking area for the site-directed mutagenesis experiments and expression in Escherichia coli. Assays of the chitinolytic activity of the purified chitinases revealed that the three mutants exhibited increased chitinolytic activity. The ChiW50A mutant exhibited a greater than 60 % increase in chitinolytic activity, with similar pH, temperature and metal ion requirements, compared to wild-type Chi9602. Furthermore, ChiW50A exhibited pest-controlling activity and antifungal activity. Remarkable synergistic effects of this mutant with B. thuringiensis spore-crystal preparations against Helicoverpa armigera and Caenorhabditis elegans larvae and obvious activity against several plant-pathogenic fungi were observed. PMID:25678849

Capacitance enhancement of polyaniline coated curved-graphene supercapacitors in a redox-active electrolyte.

PubMed

Chen, Wei; Rakhi, R B; Alshareef, H N

2013-05-21

We show, for the first time, a redox-active electrolyte in combination with a polyaniline-coated curved graphene active material to achieve significant enhancement in the capacitance (36-92% increase) compared to supercapacitors that lack the redox-active contribution from the electrolyte. The supercapacitors based on the redox-active electrolyte also exhibit excellent rate capability and very long cycling performance (>50,000 cycles).

Peroxisome proliferator-activated receptor gamma modulation and lipogenic response in adipocytes of small-for-gestational age offspring

PubMed Central

2012-01-01

Background Small-for-gestational age (SGA) at birth increases risk of development of adult obesity and insulin resistance. A model of SGA rat offspring has been shown to exhibit increased adipose tissue expression of a key adipogenic transcription factor, peroxisome proliferator-activated receptor gamma (PPARγ), and increased fatty acid de novo synthesis during the nursing period, prior to onset of obesity. PPARγ agonists have been studied for potential use in the prevention of insulin resistance. Moreover, SGA adipocytes exhibit age-dependent differences in lipogenesis as mediated by PPARγ. The effects of PPARγ modulators on lipogenic gene expression and de novo lipogenesis on the age-dependent changes in SGA adipocytes are not known. The objectives of this study were: 1) to determine the adipogenic and lipogenic potential in SGA adipocytes at postnatal day 1 (p1) and day 21 (p21), 2) to determine how the PPARγ activator- and repressor-ligands affect the lipogenic potential, and 3) to determine the fatty acid metabolic response to PPARγ activator-ligand treatment. Methods Primary adipocyte cultures from p1 and p21 SGA and Control male offspring were established from a known maternal food-restriction model of SGA. Cell proliferation and Oil Red O (ORO) staining were quantified. Adipocytes were treated with increasing doses of rosiglitazone or bisphenol-A diglycidyl ether (BADGE). PPARγ and SREBP1 protein expression were determined. De novo lipogenesis with rosiglitazone treatment at p21 was studied using 50% U13C-glucose and gas chromatography/mass spectrometry. Results At p1 and p21, SGA demonstrated increased cell proliferation and increased ORO staining. At p21, SGA demonstrated increased lipogenic gene expression and increased glucose-mediated fatty acid de novo synthesis compared with Controls. In response to rosiglitazone, SGA adipocytes further increased glucose utilization for fatty acid synthesis. SGA lipogenic gene expression demonstrated resistance to BADGE treatment. Conclusions SGA adipocytes exhibit an enhanced adipogenic and lipogenic potential in early postnatal life. By p21, SGA demonstrated resistance to PPARγ repressor-ligand treatment, and selective response to high dose PPARγ activator-ligand treatment in adipogenic and lipogenic gene expression. p21 SGA adipocytes revealed increased fatty acid de novo synthesis through a complex relationship with glucose metabolism. PMID:22726273

Adiponectin regulates albuminuria and podocyte function in mice

PubMed Central

Sharma, Kumar; RamachandraRao, Satish; Qiu, Gang; Usui, Hitomi Kataoka; Zhu, Yanqing; Dunn, Stephen R.; Ouedraogo, Raogo; Hough, Kelly; McCue, Peter; Chan, Lawrence; Falkner, Bonita; Goldstein, Barry J.

2008-01-01

Increased albuminuria is associated with obesity and diabetes and is a risk factor for cardiovascular and renal disease. However, the link between early albuminuria and adiposity remains unclear. To determine whether adiponectin, an adipocyte-derived hormone, is a communication signal between adipocytes and the kidney, we performed studies in a cohort of patients at high risk for diabetes and kidney disease as well as in adiponectin-knockout (Ad–/–) mice. Albuminuria had a negative correlation with plasma adiponectin in obese patients, and Ad–/– mice exhibited increased albuminuria and fusion of podocyte foot processes. In cultured podocytes, adiponectin administration was associated with increased activity of AMPK, and both adiponectin and AMPK activation reduced podocyte permeability to albumin and podocyte dysfunction, as evidenced by zona occludens–1 translocation to the membrane. These effects seemed to be caused by reduction of oxidative stress, as adiponectin and AMPK activation both reduced protein levels of the NADPH oxidase Nox4 in podocytes. Ad–/– mice treated with adiponectin exhibited normalization of albuminuria, improvement of podocyte foot process effacement, increased glomerular AMPK activation, and reduced urinary and glomerular markers of oxidant stress. These results suggest that adiponectin is a key regulator of albuminuria, likely acting through the AMPK pathway to modulate oxidant stress in podocytes. PMID:18431508

Robust, synergistic regulation of human gene expression using TALE activators.

PubMed

Maeder, Morgan L; Linder, Samantha J; Reyon, Deepak; Angstman, James F; Fu, Yanfang; Sander, Jeffry D; Joung, J Keith

2013-03-01

Artificial activators designed using transcription activator-like effector (TALE) technology have broad utility, but previous studies suggest that these monomeric proteins often exhibit low activities. Here we demonstrate that TALE activators can robustly function individually or in synergistic combinations to increase expression of endogenous human genes over wide dynamic ranges. These findings will encourage applications of TALE activators for research and therapy, and guide design of monomeric TALE-based fusion proteins.

Functional characterization and modified rescue of novel AE1 mutation R730C associated with overhydrated cation leak stomatocytosis.

PubMed

Stewart, Andrew K; Kedar, Prabhakar S; Shmukler, Boris E; Vandorpe, David H; Hsu, Ann; Glader, Bertil; Rivera, Alicia; Brugnara, Carlo; Alper, Seth L

2011-05-01

We report the novel, heterozygous AE1 mutation R730C associated with dominant, overhydrated, cation leak stomatocytosis and well-compensated anemia. Parallel elevations of red blood cell cation leak and ouabain-sensitive Na(+) efflux (pump activity) were apparently unaccompanied by increased erythroid cation channel-like activity, and defined ouabain-insensitive Na(+) efflux pathways of nystatin-treated cells were reduced. Epitope-tagged AE1 R730C at the Xenopus laevis oocyte surface exhibited severely reduced Cl(-) transport insensitive to rescue by glycophorin A (GPA) coexpression or by methanethiosulfonate (MTS) treatment. AE1 mutant R730K preserved Cl(-) transport activity, but R730 substitution with I, E, or H inactivated Cl(-) transport. AE1 R730C expression substantially increased endogenous oocyte Na(+)-K(+)-ATPase-mediated (86)Rb(+) influx, but ouabain-insensitive flux was minimally increased and GPA-insensitive. The reduced AE1 R730C-mediated sulfate influx did not exhibit the wild-type pattern of stimulation by acidic extracellular pH (pH(o)) and, unexpectedly, was partially rescued by exposure to sodium 2-sulfonatoethyl methanethiosulfonate (MTSES) but not to 2-aminoethyl methanethiosulfonate hydrobromide (MTSEA) or 2-(trimethylammonium)ethyl methanethiosulfonate bromide (MTSET). AE1 R730E correspondingly exhibited acid pH(o)-stimulated sulfate uptake at rates exceeding those of wild-type AE1 and AE1 R730K, whereas mutants R730I and R730H were inactive and pH(o) insensitive. MTSES-treated oocytes expressing AE1 R730C and untreated oocytes expressing AE1 R730E also exhibited unprecedented stimulation of Cl(-) influx by acid pH(o). Thus recombinant cation-leak stomatocytosis mutant AE1 R730C exhibits severely reduced anion transport unaccompanied by increased Rb(+) and Li(+) influxes. Selective rescue of acid pH(o)-stimulated sulfate uptake and conferral of acid pH(o)-stimulated Cl(-) influx, by AE1 R730E and MTSES-treated R730C, define residue R730 as critical to selectivity and regulation of anion transport by AE1.

Aldosterone Activates Transcription Factor Nrf2 in Kidney Cells Both In Vitro and In Vivo

PubMed Central

Oteiza, Patricia I.; Link, Samuel; Hey, Valentin; Stopper, Helga; Schupp, Nicole

2014-01-01

Abstract Aims: An increased kidney cancer risk was found in hypertensive patients, who frequently exhibit hyperaldosteronism, known to contribute to kidney injury, with oxidative stress playing an important role. The capacity of kidney cells to up-regulate transcription factor nuclear factor-erythroid-2-related factor 2 (Nrf2), a key regulator of the cellular antioxidative defense, as a prevention of aldosterone-induced oxidative damage was investigated both in vitro and in vivo. Results: Aldosterone activated Nrf2 and increased the expression of enzymes involved in glutathione (GSH) synthesis and detoxification. This activation depended on the mineralocorticoid receptor (MR) and oxidative stress. In vitro, Nrf2 activation, GSH amounts, and target gene levels decreased after 24 h, while oxidant levels remained high. Nrf2 activation could not protect cells against oxidative DNA damage, as aldosterone-induced double-strand breaks and 7,8-dihydro-8-oxo-guanine (8-oxodG) lesions steadily rose. The Nrf2 activator sulforaphane enhanced the Nrf2 response both in vitro and in vivo, thereby preventing aldosterone-induced DNA damage. In vivo, Nrf2 activation further had beneficial effects on the aldosterone-caused blood pressure increase and loss of kidney function. Innovation: This is the first study showing the activation of Nrf2 by aldosterone. Moreover, the results identify sulforaphane as a substance that is capable of preventing aldosterone-induced damage both in vivo and in vitro. Conclusion: Aldosterone-induced Nrf2 adaptive response cannot neutralize oxidative actions of chronically increased aldosterone, which, therefore could be causally involved in the increased cancer incidence of hypertensive individuals. Enhancing the cellular antioxidative defense with sulforaphane might exhibit beneficial effects. Antioxid. Redox Signal. 21, 2126–2142. PMID:24512358

Weaker Seniors Exhibit Motor Cortex Hypoexcitability and Impairments in Voluntary Activation.

PubMed

Clark, Brian C; Taylor, Janet L; Hong, S Lee; Law, Timothy D; Russ, David W

2015-09-01

Weakness predisposes seniors to a fourfold increase in functional limitations. The potential for age-related degradation in nervous system function to contribute to weakness and physical disability has garnered much interest of late. In this study, we tested the hypothesis that weaker seniors have impairments in voluntary (neural) activation and increased indices of GABAergic inhibition of the motor cortex, assessed using transcranial magnetic stimulation. Young adults (N = 46; 21.2±0.5 years) and seniors (N = 42; 70.7±0.9 years) had their wrist flexion strength quantified along with voluntary activation capacity (by comparing voluntary and electrically evoked forces). Single-pulse transcranial magnetic stimulation was used to measure motor-evoked potential amplitude and silent period duration during isometric contractions at 15% and 30% of maximum strength. Paired-pulse transcranial magnetic stimulation was used to measure intracortical facilitation and short-interval and long-interval intracortical inhibition. The primary analysis compared seniors to young adults. The secondary analysis compared stronger seniors (top two tertiles) to weaker seniors (bottom tertile) based on strength relative to body weight. The most novel findings were that weaker seniors exhibited: (i) a 20% deficit in voluntary activation; (ii) ~20% smaller motor-evoked potentials during the 30% contraction task; and (iii) nearly twofold higher levels of long-interval intracortical inhibition under resting conditions. These findings indicate that weaker seniors exhibit significant impairments in voluntary activation, and that this impairment may be mechanistically associated with increased GABAergic inhibition of the motor cortex. © The Author 2015. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Cystic Fibrosis Transmembrane Conductance Regulator Controls Lung Proteasomal Degradation and Nuclear Factor-κB Activity in Conditions of Oxidative Stress

PubMed Central

Boncoeur, Emilie; Roque, Telma; Bonvin, Elise; Saint-Criq, Vinciane; Bonora, Monique; Clement, Annick; Tabary, Olivier; Henrion-Caude, Alexandra; Jacquot, Jacky

2008-01-01

Cystic fibrosis is a lethal inherited disorder caused by mutations in a single gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein, resulting in progressive oxidative lung damage. In this study, we evaluated the role of CFTR in the control of ubiquitin-proteasome activity and nuclear factor (NF)-κB/IκB-α signaling after lung oxidative stress. After a 64-hour exposure to hyperoxia-mediated oxidative stress, CFTR-deficient (cftr−/−) mice exhibited significantly elevated lung proteasomal activity compared with wild-type (cftr+/+) animals. This was accompanied by reduced lung caspase-3 activity and defective degradation of NF-κB inhibitor IκB-α. In vitro, human CFTR-deficient lung cells exposed to oxidative stress exhibited increased proteasomal activity and decreased NF-κB-dependent transcriptional activity compared with CFTR-sufficient lung cells. Inhibition of the CFTR Cl− channel by CFTRinh-172 in the normal bronchial immortalized cell line 16HBE14o− increased proteasomal degradation after exposure to oxidative stress. Caspase-3 inhibition by Z-DQMD in CFTR-sufficient lung cells mimicked the response profile of increased proteasomal degradation and reduced NF-κB activity observed in CFTR-deficient lung cells exposed to oxidative stress. Taken together, these results suggest that functional CFTR Cl− channel activity is crucial for regulation of lung proteasomal degradation and NF-κB activity in conditions of oxidative stress. PMID:18372427

Cue-induced brain activity in pathological gamblers.

PubMed

Crockford, David N; Goodyear, Bradley; Edwards, Jodi; Quickfall, Jeremy; el-Guebaly, Nady

2005-11-15

Previous studies using functional magnetic resonance imaging (fMRI) have identified differential brain activity in healthy subjects performing gambling tasks and in pathological gambling (PG) subjects when exposed to motivational and emotional predecessors for gambling as well as during gambling or response inhibition tasks. The goal of the present study was to determine if PG subjects exhibit differential brain activity when exposed to visual gambling cues. Ten male DSM-IV-TR PG subjects and 10 matched healthy control subjects underwent fMRI during visual presentations of gambling-related video alternating with video of nature scenes. Pathological gambling subjects and control subjects exhibited overlap in areas of brain activity in response to the visual gambling cues; however, compared with control subjects, PG subjects exhibited significantly greater activity in the right dorsolateral prefrontal cortex (DLPFC), including the inferior and medial frontal gyri, the right parahippocampal gyrus, and left occipital cortex, including the fusiform gyrus. Pathological gambling subjects also reported a significant increase in mean craving for gambling after the study. Post hoc analyses revealed a dissociation in visual processing stream (dorsal vs. ventral) activation by subject group and cue type. These findings may represent a component of cue-induced craving for gambling or conditioned behavior that could underlie pathological gambling.

Carcinogen-induced squamous papillomas and oncogenic progression in the absence of the SSeCKS/AKAP12 metastasis suppressor correlates with FAK upregulation

PubMed Central

Akakura, Shin; Bouchard, Rene; Bshara, Wiam; Morrison, Carl; Gelman, Irwin H.

2011-01-01

The ability of SSeCKS/Gravin/AKAP12 (SSeCKS) to negatively regulate cell cycle progression is thought to relate to its spatiotemporal scaffolding activity for key signaling molecules such as protein kinase A and C, calmodulin, and cyclins. SSeCKS is downregulated upon progression to malignancy in many cancer types, including melanoma and non-melanoma skin cancer. The forced re-expression of SSeCKS is especially potent in suppressing metastasis through the inhibition of VEGF-mediated neovascularization. We have previously shown that SSeCKS-null (KO) mice exhibit hyperplasia and focal dysplasia in the prostate marked by activated Akt. To address whether KO-mice exhibit increased skin carcinogenesis, WT and KO C57BL/6 mice were treated topically with 12-O-tetradecanoylphorbol-13-acetate and 7,12-dimethylbenzanthracene. Compared to WT mice, KO mice developed squamous papillomas more rapidly and in greater numbers, and also exhibited significantly increased progression to squamous cell carcinoma. Untreated KO epidermal layers were thicker than those in age-matched WT mice, and exhibited significantly increased levels of FAK and phospho-ERK1/2, known mediators of carcinogen-induced squamous papilloma progression to carcinoma. Compared to protein levels in WT mouse embryo fibroblasts (MEF), SSeCKS levels were increased in FAK-null cells whereas FAK levels were increased in SSeCKS-null cells. RNAi studies in WT MEF cells suggest that SSeCKS and FAK attenuate each other’s expression. Our study implicates a role for SSeCKS in preventing of skin cancer progression possibly through negatively regulating FAK expression. PMID:21128249

The Influence of Body Mass Index, Sex, & Muscle Activation on Pressure Distribution During Lateral Falls on the Hip.

PubMed

Pretty, Steven P; Martel, Daniel R; Laing, Andrew C

2017-12-01

Hip fracture incidence rates are influenced by body mass index (BMI) and sex, likely through mechanistic pathways that influence dynamics of the pelvis-femur system during fall-related impacts. The goal of this study was to extend our understanding of these impact dynamics by investigating the effects of BMI, sex, and local muscle activation on pressure distribution over the hip region during lateral impacts. Twenty participants underwent "pelvis-release experiments" (which simulate a lateral fall onto the hip), including muscle-'relaxed' and 'contracted' trials. Males and low-BMI individuals exhibited 44 and 55% greater peak pressure, as well as 66 and 56% lower peripheral hip force, compared to females and high-BMI individuals, respectively. Local muscle activation increased peak force by 10%, contact area by 17%, and peripheral hip force by 11% compared to relaxed trials. In summary, males and low-BMI individuals exhibited more concentrated loading over the greater trochanter. Muscle activation increased peak force, but this force was distributed over a larger area, preventing increased localized loading over the greater trochanter. These findings suggest potential value in incorporating sex, gender, and muscle activation-specific force distributions as inputs into computational tissue-level models, and have implications for the design of personalized protective devices including wearable hip protectors.

Impact of ultraviolet radiation treatments on the quality of freshly prepared tomato (Solanum lycopersicum) juice.

PubMed

Bhat, Rajeev

2016-12-15

Impact of ultraviolet (UV-C) radiation treatments (0, 15, 30 and 60min) on freshly extracted tomato juice quality (physicochemical properties, antioxidant activity and microbial load) was evaluated. On exposure to UV-C, level of water activity, total soluble solids, and titratable acidity exhibited non-significant increase up to 30min of exposure time. Regarding colour analysis, L∗ value significantly increased with subsequent decrease in a∗ and b∗ values post UV-C treatments. Clarity, DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity and total phenolics content significantly increased, whereas ascorbic acid level significantly reduced at 60min of UV-C exposure time. So also, lycopene content exhibited a non-significant decrease after UV-C treatment. Microbial studies showed reduction in total plate count and total mould counts post UV-C treatment. Overall, UV-C treatment being a physical, non-thermal method of food preservation holds the ability to improve or preserve vital quality parameters in freshly prepared tomato juices, and henceforth possesses high scope for commercial exploration. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hepatic FGF21 expression is induced at birth via PPARalpha in response to milk intake and contributes to thermogenic activation of neonatal brown fat.

PubMed

Hondares, Elayne; Rosell, Meritxell; Gonzalez, Frank J; Giralt, Marta; Iglesias, Roser; Villarroya, Francesc

2010-03-03

Plasma FGF21 levels and hepatic FGF21 gene expression increase dramatically after birth in mice. This induction is initiated by suckling, requires lipid intake, is impaired in PPARalpha null neonates, and is mimicked by treatment with the PPARalpha activator, Wy14,643. Neonates exhibit reduced FGF21 expression in response to fasting, in contrast to the upregulation occurring in adults. Changes in FGF21 expression due to suckling or nutritional manipulations were associated with circulating free fatty acid and ketone body levels. We mimicked the FGF21 postnatal rise by injecting FGF21 into fasting neonates, and found that this enhanced the expression of genes involved in thermogenesis within brown fat, and increased body temperature. Brown adipocytes treated with FGF21 exhibited increased expression of thermogenic genes, higher total and uncoupled respiration, and enhanced glucose oxidation. We propose that the induction of FGF21 production by the liver mediates direct activation of brown fat thermogenesis during the fetal-to-neonatal transition. 2010 Elsevier Inc. All rights reserved.

Sex-dimorphic psychomotor activation after perinatal exposure to (-)-delta 9-tetrahydrocannabinol. An ontogenic study in Wistar rats.

PubMed

Navarro, M; Rubio, P; Rodríguez de Fonseca, F

1994-12-01

The ontogeny and the adult expression of motor behaviors were studied in male and female rats born from mothers exposed to delta 9-tetrahydrocannabinol (THC, 5 mg/kg) during gestation and lactation. Perinatal exposure to THC increased both rearing and locomotor activities in males and females at immature preweanling ages (P-15 and P-20). These effects disappeared after ceasing THC exposure (postweaning ages), but they were observed again in adult (P-70) females. The effects appeared as persistently high motor activity in familiar environments, disappearing the characteristic habituation profile in locomotor and exploratory behaviors. In novel environment condition tests, adult (P-70) THC-exposed females, but not males, exhibited lower locomotor activity in the socio-sexual approach test, and an increase in the emergence latency in the dark-light emergence test. Additionally, animals of both sexes exposed to THC showed a increase in the time spent grooming measured in novelty conditions. These findings suggest that perinatal exposure to THC affects both the development and the adult expression of motor behaviors and it resulted in a sex-dimorphic psychomotor activation very similar to that observed after perinatal exposure to other drugs of abuse. A possible role of THC-induced pituitary-adrenal (PA) axis activation was also evaluated by measuring plasma corticosterone levels in adult animals perinatally exposed: THC-exposed females exhibit a clear increase of this adrenal hormone, whereas THC-exposed males displayed lower levels of this hormone.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization and antimicrobial activity of sweetpotato starch-based edible film containing origanum (Thymus capitatus) oil.

PubMed

Ehivet, Fabienne E; Min, Byungjin; Park, Mi-Kyung; Oh, Jun-Hyun

2011-01-01

The objectives of this research were to characterize the mechanical and barrier properties of sweetpotato starch (SPS)-based film (SPSF) and to investigate the antimicrobial activity of SPSF containing origanum oil (OG) against foodborne pathogenic bacteria. The SPSF was fabricated with the SPS extracted from commercial sweetpotato roots. Tensile strength (TS), percent elongation at break (E), and water vapor permeability (WVP) were determined to characterize the SPSF fabricated with selected SPS concentrations, plasticizers, and the concentrations of plasticizers. The agar diffusion assay was used to determine the antimicrobial activity of SPSF containing selective concentrations of OG against Salmonella Enteritidis, Escherichia coli O157:H7, and Listeria monocytogenes. The SPSF fabricated with 2.5% SPS exhibited the greatest TS (4.58 MPa). The TS, E, and WVP of SPSF plasticized with 40% sorbitol exhibited 7.96 MPa, 77.92%, 0.212 ng m/m(2) S Pa, respectively. Therefore, the SPSF fabricated with 2.5% SPS and 40% sorbitol was determined as the optimum film. The antimicrobial activity of the SPSF containing OG increased as the concentration of OG increased. And the SPSF containing OG exhibited greater inhibitory effects against the gram-negative bacteria such as S. Enteritidis and E. coli O157:H7 than the gram-positive L. monocytogenes. The greatest antimicrobial activity was observed against S. Enteritidis when the SPSF containing 2% OG was applied, and the maximum square of zone width was 18.43 mm(2).

Stellar model chromospheres. IX - Chromospheric activity in dwarf stars

NASA Technical Reports Server (NTRS)

Kelch, W. L.; Worden, S. P.; Linsky, J. L.

1979-01-01

High-resolution Ca II K line profiles are used to model the upper photospheres and lower chromospheres of eight main-sequence stars ranging in spectral type from F0 to M0 and exhibiting different degrees of chromospheric activity. The model chromospheres are studied as a function of spectral type and activity for stars of similar spectral type in order to obtain evidence of enhanced nonradiative heating in the upper-photospheric models and in the ratio of minimum temperature at the base of the chromosphere to effective temperature, a correlation between activity and temperature in the lower chromospheres, and a correlation of the width at the base of the K-line emission core and at the K2 features with activity. Chromospheric radiative losses are estimated for the modelled stars and other previously analyzed main-sequence stars. The results obtained strengthen the argument that dMe flare stars exhibit fundamentally solar-type activity but on an increased scale.

Behavioral and Neural Sustained Attention Deficits in Disruptive Mood Dysregulation Disorder and Attention-Deficit/Hyperactivity Disorder

PubMed Central

Pagliaccio, David; Wiggins, Jillian Lee; Adleman, Nancy E.; Curhan, Alexa; Zhang, Susan; Towbin, Kenneth E.; Brotman, Melissa A.; Pine, Daniel S.; Leibenluft, Ellen

2017-01-01

Objective Disruptive mood dysregulation disorder (DMDD), characterized by severe irritability, and attention-deficit/hyperactivity disorder (ADHD) are highly comorbid. This is the first study to characterize neural and behavioral similarities and differences in attentional functioning across these disorders. Method Twenty-seven healthy volunteers, 31 patients with DMDD, and 25 patients with ADHD (8–18-year-olds) completed a functional magnetic resonance imaging (fMRI) attention task. Group differences in intra-subject variability in reaction time (ISVRT) were examined. The current fMRI analytic approach precisely quantified trial-wise associations between reaction time and brain activity. Results Group differences manifested in the relationship between reaction time and brain activity (all regions: p<.01, F>2.54, ηp2>0.06). Patients with DMDD showed specific alterations in the right paracentral lobule, superior parietal lobule, fusiform gyrus, and cerebellar culmen. In contrast, both patients with DMDD and ADHD exhibited blunted compensatory increases in activity on long reaction time trials. Additionally, youth with DMDD exhibited increased activity in the postcentral gyrus, medial frontal gyrus, and cerebellar tonsil and declive (all regions: p<.05, F>2.46, ηp2>0.06). The groups in the imaging sample did not differ significantly in ISVRT (F[2,79]=2.664, p=.076, ηp2=0.063), though ISVRT was significantly elevated among youth with DMDD and ADHD when including those not meeting strict motion and accuracy criteria for the imaging analysis (F[2,96]=4.283, p=.017, ηp2=0.083). Conclusion Patients with DMDD exhibited specific alterations in the relationship between pre-stimulus brain activity and reaction time. Both patients with DMDD and ADHD exhibited similar blunting of compensatory neural activity in frontal, parietal, and other regions. Additionally, patients with DMDD demonstrated elevated reaction time variability relative to healthy youth. This work is the first to identify common and unique behavioral and neural signatures of DMDD and ADHD. PMID:28433092

Honey melanoidins: Analysis of the compositions of the high molecular weight melanoidins exhibiting radical-scavenging activity.

PubMed

Brudzynski, Katrina; Miotto, Danielle

2011-08-01

Size-exclusion chromatography (SEC) and activity-guided fractionation of honeys allowed the isolation of high molecular weight brown compounds, ranging in size from 66 to 235kDa that exhibited peroxyl radical-scavenging activity. Their concentrations, antioxidant activity and degree of browning increased after heat-treatment of honeys, suggesting that they represent melanoidins. Chemical analysis of melanoidins demonstrated the presence of proteins, polyphenols and oligosaccharides. Heat-treatment caused an increased incorporation of phenolics into high molecular weight melanoidins and drastically decreased the protein content in these fractions with a concomitant appearance of high molecular weight protein-polyphenol complexes of reduced solubility. LC-ESI-MS demonstrated the presence of oligosaccharide moieties, supporting the postulated origin of melanoidins. The changes in the phenolic content of melanoidins from heated honeys were strongly correlated with their oxygen radical absorbance capacity (ORAC) values (R=0.75, p<0.0001), indicating that polyphenols contribute to the antioxidant activity of melanoidins. In summary, honey melanoidins are multi-component polymers consisting of protein-polyphenol-oligosaccharide complexes. A direct interaction between polyphenols and melanoidins resulted in a loss or gain of function for melanoidin antioxidant activity. Copyright © 2011 Elsevier Ltd. All rights reserved.

Changes in women's sexual behavior following sexual assault.

PubMed

Deliramich, Aimee N; Gray, Matt J

2008-09-01

The present study examines changes in women's sexual activity and behavior following sexual assault and the relationship between alcohol abuse and postassault promiscuity. Although many researchers have focused on avoidance of sexual activity following an assault, some have suggested that women may exhibit an increase in sexual activity postassault. Such outcomes are not mutually exclusive possibilities but may instead reflect subtypes of sexual assault victims. A significant percentage of assault survivors did report increases in sexual activity following trauma. Assault survivors also reported increases in posttraumatic alcohol consumption relative to a comparison sample of motor vehicle accident survivors. In both groups, increases in posttraumatic alcohol usage predicted increases in posttraumatic sexual activity, suggesting that use of alcohol as a coping strategy may result in an increased likelihood of engaging in risky sexual behavior. If true, this maladaptive coping mechanism could help to account for some instances of revictimization.

Pyrrole-regulated precipitation of titania nanorods on polymer fabrics for photocatalytic degradation of trace toluene in air

NASA Astrophysics Data System (ADS)

Gu, Yi-Jie; Wen, Wei; Xu, Yang; Wu, Jin-Ming

2018-03-01

When compared with nanoparticulate counterparts, TiO2 thin films with vertically aligned one-dimensional (1D) nanostructures exhibit enhanced photocatalytic activity because of the highly accessible surface area. The perpendicular of the 1D nanostructure reduces the charge migration path and hence the carrier recombination rate, which also contributes to the photocatalytic activity. Furthermore, TiO2 thin films on flexible substrates are more suitable to degrade pollutants in either water or air because of its easy recovery and free-bending shape. In this study, flexible polyethylene fabrics were firstly coated with a sol-gel nanoparticulate TiO2 seed layer. Quasi-aligned TiO2 nanorods were then precipitated homogeneously under an atmospheric pressure and a low temperature not exceeding 80 °C, using a peroxy-titanium complex precursor with the additive of pyrrole. It is found that the density of TiO2 nanorods increased with the increasing amount of pyrrole monomers. The resultant TiO2 film on polyethylene fabrics exhibited a much reduced band gap of ca. 2.86 eV, which can be attributed to the surface oxygen deficiencies. When utilized to assist photocatalytic degradation of trace toluene in air under the UV light illumination, the TiO2 film exhibited a gradually increased photocatalytic activity upon the increasing cycles for up to six, because of the gradual removal of trace organics on the TiO2 surface. The highest photocatalytic efficiency is recorded to be 5 times that of TiO2 nanotube arrays, which are regarded as an excellent photocatalyst for air cleaning.

Alkyl Protocatechuate-Loaded Nanostructured Lipid Systems as a Treatment Strategy for Paracoccidioides brasiliensis and Paracoccidioides lutzii In Vitro

PubMed Central

Medina-Alarcón, Kaila P.; Singulani, Junya L.; Voltan, Aline R.; Sardi, Janaina C. O.; Petrônio, Maicon S.; Santos, Mariana B.; Polaquini, Carlos R.; Regasini, Luis O.; Bolzani, Vanderlan S.; da Silva, Dulce H. S.; Chorilli, Marlus; Mendes-Giannini, Maria J. S.; Fusco-Almeida, Ana M.

2017-01-01

Dodecyl protocatechuate (dodecyl) is a derivative of protocatechuic acid (3,4-dihydroxybenzoic acid) that possesses anti-oxidant and antifungal properties. Nanostructured lipid systems (NLS) can potentiate the action of many antifungal agents, reducing the required dose and side effects by improving their activity. This work aimed to evaluate dodecyl protocatechuate loaded into a NLS (NLS+dodecyl) as a strategy for the treatment of Paracoccidioides brasiliensis and P. lutzii in vitro. Antifungal activity against P. brasiliensis and P. lutzii was evaluated using the microdilution technique. NLS+dodecyl showed high antifungal activity with a minimum inhibitory concentration ranging from 0.06 to 0.03 μg/mL; 4- to 16-fold higher than that of free dodecyl. NLS+dodecyl was able to inhibit fungal adhesion of the extracellular artificial matrix proteins (laminin and fibronectin), resulting in 82.4 and 81% inhibition, respectively, an increase of 8–17% compared with free dodecyl. These findings corroborate previous results demonstrating 65 and 74% inhibition of fungal adhesion in pulmonary fibroblast cells by dodecyl and NLS+dodecyl, respectively, representing a 9% increase in inhibition for NLS+dodecyl. Subsequently, cytotoxicity was evaluated using the 0.4% sulforhodamine B assay. NLS+dodecyl did not exhibit cytotoxicity in MRC5 (human pneumocyte) and HepG2 (human hepatic carcinoma) cells, thus increasing the selectivity index for NLS+dodecyl. In addition, cytotoxicity was evaluated in vivo using the Caenorhabditis elegans model; neither dodecyl nor NLS+dodecyl exhibited any toxic effects. Taken together, these results suggest that NLS can be used as a strategy to improve the activity of dodecyl against P. brasiliensis and P. lutzii because it improves antifungal activity, increases the inhibition of fungal adhesion in lung cells and the extracellular matrix in vitro, and does not exhibit any toxicity both in vitro and in vivo. PMID:28659880

Habitat use by fishes of Lake Superior. I. Diel patterns of habitat use in nearshore and offshore waters of the Apostle Islands region

USGS Publications Warehouse

Gorman, O.T.; Yule, D.L.; Stockwell, J.D.

2012-01-01

Diel patterns of distribution of fishes in nearshore (15–80 m depth) and offshore (>80 m) waters of the Apostle Islands region of Lake Superior were described using bottom trawls, mid-water trawls, and acoustic gear during day and night sampling. These data revealed three types of diel migration: diel vertical migration (DVM), diel bank migration (DBM), and no migration. DVM was expressed by fishes migrating from benthopelagic to pelagic strata and DBM was expressed by fishes migrating horizontally from deeper waters in the day to shallower waters at night while remaining within the benthopelagic stratum. Most fishes that did not exhibit diel migration showed increased nighttime densities as a result of increased activity and movement from benthic to benthopelagic strata. Rainbow Smelt (Osmerus mordax), Cisco (Coregonus artedi), Bloater (C. hoyi), Kiyi (C. kiyi), juvenile Trout-Perch (Percopsis omiscomaycus), and adult siscowet (Salvelinus namaycush siscowet) exhibited DVM. Lake Whitefish (C. clupeaformis), lean Lake Trout (Salvelinus namaycush namaycush), and juvenile siscowet exhibited DBM. Adult Trout-Perch and adult Pygmy Whitefish (Prosopium coulteri) exhibited a mixture of DBM and DVM. Burbot (Lota lota), Slimy Sculpin (Cottus cognatus), Spoonhead Sculpin (C. ricei), and Deepwater Sculpin (Myoxocephalus thompsonii) did not exhibit diel migration, but showed evidence of increased nocturnal activity. Ninespine Stickleback (Pungitius pungitius) exhibited a mixture of DVM and non-migration. Juvenile Pygmy Whitefish did not show a diel change in density or depth distribution. Species showing ontogenetic shifts in depth distribution with larger, adult life stages occupying deeper waters included, Rainbow Smelt, lean and siscowet Lake Trout, Lake Whitefish, Pygmy Whitefish, Ninespine Stickleback and Trout-Perch. Of these species, siscowet also showed an ontogenetic shift from primarily DBM as juveniles to primarily DVM as adults. Across all depths, fishes expressing DVM accounted for 73% of the total estimated community areal biomass (kg ha−1) while those expressing DBM accounted for 25% and non-migratory species represented 2% of the biomass. The proportion of total community biomass exhibiting DVM increased with depth, from 59% to 95% across ≤30 m to >90 m depth zones. Along the same depth gradient, the proportion of total community biomass exhibiting DBM declined from 40% to 1%, while non-migrators increased from 1% to 4%. These results indicate that DVM and DBM behaviors are pervasive in the Lake Superior fish community and potentially provide strong linkages that effect coupling of benthic and pelagic and nearshore and offshore habitats.

Arginase 2 deletion leads to enhanced M1 macrophage activation and upregulated polyamine metabolism in response to Helicobacter pylori infection

PubMed Central

Hardbower, Dana M.; Asim, Mohammad; Murray-Stewart, Tracy; Casero, Robert A.; Verriere, Thomas; Lewis, Nuruddeen D.; Chaturvedi, Rupesh; Piazuelo, M. Blanca; Wilson, Keith T.

2016-01-01

We reported that arginase 2 (ARG2) deletion results in increased gastritis and decreased bacterial burden during Helicobacter pylori infection in mice. Our studies implicated a potential role for inducible nitric oxide (NO) synthase (NOS2), as Arg2−/− mice exhibited increased NOS2 levels in gastric macrophages, and NO can kill H. pylori. We now bred Arg2−/− to Nos2−/− mice, and infected them with H. pylori. Compared to wild-type mice, both Arg2−/− and Arg2−/−;Nos2−/− mice exhibited increased gastritis and decreased colonization, the latter indicating that the effect of ARG2 deletion on bacterial burden was not mediated by NO. While Arg2−/− mice demonstrated enhanced M1 macrophage activation, Nos2−/− and Arg2−/−;Nos2−/− mice did not demonstrate these changes, but exhibited increased CXCL1 and CXCL2 responses. There was an increased expression of the Th1/ Th17 cytokines, interferon gamma and interleukin 17, in gastric tissues and splenic T-cells from Arg2−/−, but not Nos2−/− or Arg2−/−;Nos2−/− mice. Gastric tissues from infected Arg2−/− mice demonstrated increased expression of arginase 1, ornithine decarboxylase, adenosylmethionine decarboxylase 1, spermidine/spermine N1-acetyltransferase 1, and spermine oxidase, along with increased spermine levels. These data indicate that ARG2 deletion results in compensatory upregulation of gastric polyamine synthesis and catabolism during H. pylori infection, which may contribute to increased gastric inflammation and associated decreased bacterial load. Overall, the finding of this study is that ARG2 contributes to the immune evasion of H. pylori by restricting M1 macrophage activation and polyamine metabolism. PMID:27074721

Evaluation of wound healing, anti-microbial and antioxidant potential of Pongamia pinnata in wistar rats.

PubMed

Dwivedi, Deepak; Dwivedi, Mona; Malviya, Sourabh; Singh, Vinod

2017-01-01

To investigate wound healing, antimicrobial and antioxidant activity of leaf extract of Pongamia Pinnata . Methanolic extracts of P. pinnata leaf were studied for wound healing efficiency, and was assessed by the rate of wound contraction, tensile strength, breaking strength, hydroxyproline and hexosamine content, along with its effect on pro-inflammatory and anti-inflammatory cytokines was assessed using excision and incision model of wound repair in Wistar rats. Antimicrobial activity against ten microorganisms was also assessed. In vivo antioxidant activity was performed to understand the mechanism of wound healing potency. The results indicated that P. pinnata extract has potent wound healing capacity as evident from the wound contraction and increased tensile strength. Hydroxyproline and hexosamine expression were also well correlated with the healing pattern observed. extract exhibited significant antimicrobial activity, Staphylococcus aureus, Staphylococcus pyogenes, Staphylococcus epidermidis, Escherichia coli, Micrococcus luteus, Enterobacter aerogenes, Salmonella typhi, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger also indicate that P. pinnata posses potent antioxidant activity by inhibition lipid peroxidation, reduce glutathione, superoxide dismutase level and increases catalase activity. During early wound healing phase TNF-α and IL-6 level were found to be up-regulated by P. pinnata treatment. Increased wound contraction and tensile strength, augmented hydroxyproline and hexosamine content, antioxidative activity and moderate antimicrobial activity support the early wound healing exhibited by P. pinnata . Induction in cytokine production may be one of the mechanisms in accelerating the wound healing. Results suggest that P. pinnata may be useful in tropical management of wound healing.

Depression-related increases and decreases in appetite reveal dissociable patterns of aberrant activity in reward and interoceptive neurocircuitry

PubMed Central

Simmons, W. Kyle; Burrows, Kaiping; Avery, Jason A.; Kerr, Kara L.; Bodurka, Jerzy; Savage, Cary R.; Drevets, Wayne C.

2016-01-01

Objective Appetite and weight changes are common but variable diagnostic markers in major depressive disorder: some depressed individuals manifest increased appetite, while others lose their appetite. Many of the brain regions implicated in appetitive responses to food have also been implicated in depression. It is thus remarkable that there exists no published research comparing the neural responses to food stimuli of depressed patients with increased versus decreased appetites. Method Using functional magnetic resonance imaging we compared brain activity in unmedicated depressed patients with increased or decreased appetite, and healthy control subjects, while viewing photographs of food and non-food objects. We also measured how resting-state functional connectivity related to subjects’ food pleasantness ratings. Results Within putative reward regions, depressed participants with increased appetites exhibited greater hemodynamic activity to food stimuli than both those reporting appetite decreases and healthy control subjects. In contrast, depressed subjects experiencing appetite loss exhibited hypoactivation within a region of the mid-insula implicated in interoception, with no difference observed in this region between healthy subjects and those with depression-related appetite increases. Mid-insula activity was negatively correlated with food pleasantness ratings of depressed participants with increased appetites, and its functional connectivity to reward circuitry was positively correlated with food pleasantness ratings. Conclusions Depression-related increases in appetite are associated with hyperactivation of putative mesocorticolimbic reward circuitry, while depression-related appetite loss is associated with hypoactivation of insular regions that support monitoring the body’s physiological state. Importantly, the interactions among these regions also contribute to individual differences in the depression-related appetite changes. PMID:26806872

Depression-Related Increases and Decreases in Appetite: Dissociable Patterns of Aberrant Activity in Reward and Interoceptive Neurocircuitry.

PubMed

Simmons, W Kyle; Burrows, Kaiping; Avery, Jason A; Kerr, Kara L; Bodurka, Jerzy; Savage, Cary R; Drevets, Wayne C

2016-04-01

Appetite and weight changes are common but variable diagnostic markers in major depressive disorder: some depressed individuals manifest increased appetite, while others lose their appetite. Many of the brain regions implicated in appetitive responses to food have also been implicated in depression. It is thus remarkable that there exists no published research comparing the neural responses to food stimuli of depressed patients with increased versus decreased appetites. Using functional MRI, brain activity was compared in unmedicated depressed patients with increased or decreased appetite and healthy control subjects while viewing photographs of food and nonfood objects. The authors also measured how resting-state functional connectivity related to subjects' food pleasantness ratings. Within putative reward regions, depressed participants with increased appetites exhibited greater hemodynamic activity to food stimuli than both those reporting appetite decreases and healthy control subjects. In contrast, depressed subjects experiencing appetite loss exhibited hypoactivation within a region of the mid-insula implicated in interoception, with no difference observed in this region between healthy subjects and those with depression-related appetite increases. Mid-insula activity was negatively correlated with food pleasantness ratings of depressed participants with increased appetites, and its functional connectivity to reward circuitry was positively correlated with food pleasantness ratings. Depression-related increases in appetite are associated with hyperactivation of putative mesocorticolimbic reward circuitry, while depression-related appetite loss is associated with hypoactivation of insular regions that support monitoring the body's physiological state. Importantly, the interactions among these regions also contribute to individual differences in the depression-related appetite changes.

Muscle activation patterns in the Nordic hamstring exercise: Impact of prior strain injury.

PubMed

Bourne, M N; Opar, D A; Williams, M D; Al Najjar, A; Shield, A J

2016-06-01

This study aimed to determine: (a) the spatial patterns of hamstring activation during the Nordic hamstring exercise (NHE); (b) whether previously injured hamstrings display activation deficits during the NHE; and (c) whether previously injured hamstrings exhibit altered cross-sectional area (CSA). Ten healthy, recreationally active men with a history of unilateral hamstring strain injury underwent functional magnetic resonance imaging of their thighs before and after six sets of 10 repetitions of the NHE. Transverse (T2) relaxation times of all hamstring muscles [biceps femoris long head (BFlh); biceps femoris short head (BFsh); semitendinosus (ST); semimembranosus (SM)] were measured at rest and immediately after the NHE and CSA was measured at rest. For the uninjured limb, the ST's percentage increase in T2 with exercise was 16.8%, 15.8%, and 20.2% greater than the increases exhibited by the BFlh, BFsh, and SM, respectively (P < 0.002 for all). Previously injured hamstring muscles (n = 10) displayed significantly smaller increases in T2 post-exercise than the homonymous muscles in the uninjured contralateral limb (mean difference -7.2%, P = 0.001). No muscles displayed significant between-limb differences in CSA. During the NHE, the ST is preferentially activated and previously injured hamstring muscles display chronic activation deficits compared with uninjured contralateral muscles. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The Influence of Learning on Cortical Activation Patterns.

ERIC Educational Resources Information Center

Gruhn, Wilfried; Altenmuller, Eckart; Babler, Roman

1997-01-01

Investigates the psychological and neurobiological aspects of music learning that is described as a process of incrementally differentiating mental representations. Finds that the verbally trained subjects exhibited an increase over the left cortex whereas the musically trained showed an increase over the right and bilateral brain areas; the…

Melatonin and nitric oxide modulate glutathione content and glutathione reductase activity in sunflower seedling cotyledons accompanying salt stress.

PubMed

Kaur, Harmeet; Bhatla, Satish C

2016-09-30

The present findings demonstrate significant modulation of total glutathione content, reduced glutathione (GSH) content, oxidized glutathione (GSSG) content, GSH/GSSG ratio and glutathione reductase (GR; EC 1.6.4.2) activity in dark-grown seedling cotyledons in response to salt-stress (120 mM NaCl) in sunflower (Helianthus annuus L.) seedlings. A differential spatial distribution of GR activity (monitored by confocal laser scanning microscopic (CLSM) imaging) is also evident. Melatonin and nitric oxide (NO) differentially ameliorate salt stress effect by modulating GR activity and GSH content in seedling cotyledons. Total glutathione content (GSH + GSSG) exhibit a seedling age-dependent increase in the cotyledons, more so in salt-stressed conditions and when subjected to melatonin treatment. Seedlings raised in presence of 15 μM of melatonin exhibit significant increase in GR activity in cotyledon homogenates (10,000 g supernatant) coinciding with significant increase in GSH content. GSSG content and GSH/GSSG ratio also increased due to melatonin treatment. A correlation is thus evident in NaCl-sensitized modulation of GSH content and GR activity by melatonin. GSH content is down regulated by NO provided as 250 μM of sodium nitroprusside (SNP) although total glutathione content remained in similar range. A reversal of response (enhanced total glutathione accumulation) by NO scavenger (cPTIO) highlights the critical role of NO in modulating glutathione homeostasis. SNP lowers the activity of hydroxyindole-O-methyltransferase (HIOMT) - a regulatory enzyme in melatonin biosynthesis in control seedlings whereas its activity is upregulated in salt-stressed seedling cotyledons. Melatonin content of seedling cotyledons is also modulated by NO. NO and melatonin thus seem to modulate GR activity and GSH content during seedling growth under salt stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of high pressure processing on activity and structure of soluble acid invertase in mango pulp, crude extract, purified form and model systems.

PubMed

Li, Renjie; Wang, Yongtao; Ling, Jiangang; Liao, Xiaojun

2017-09-15

The effects of high pressure processing (HPP) on the activity of soluble acid invertase (SAI) in mango pulp, crude extract, purified SAI and purified SAI in model systems (pectin, bovine serum albumin (BSA), sugars and pH 3-7) were investigated. The activity of SAI in mango pulp was increased after HPP, and that in crude extract stayed unchanged. The activity of purified SAI was decreased after HPP at 45 and 50°C. Pectin exhibited a concentration-dependent protection for purified SAI against HPP at 50°C/600MPa for 30min. Pectin that had an esterification degree (DE) of 85% exhibited a greater protection than pectin that had a DE of 20-34%. BSA, acidic pH (3-6) and sucrose also exhibited protection for purified SAI against HPP. HPP at 50°C/600MPa for 30min disrupted the secondary structure and tertiary structure of purified SAI, but no aggregation of purified SAI was observed after HPP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Attenuation of acute restraint stress-induced depressive like behavior and hippocampal alterations with protocatechuic acid treatment in mice.

PubMed

Thakare, Vishnu N; Dhakane, Valmik D; Patel, Bhoomika M

2017-04-01

Protocatechuic acid ethyl ester (PCA), a phenolic compound, exhibits neuroprotective effects through improving endogenous antioxidant enzymatic and nonezymatic system. Based on the role of oxidative stress in modulating depressive disorders and the relationship between neuroprotective and antioxidant potential of PCA, we studied if its antidepressant like effect is associated by modulation of cerebral cortex and hippocampal antioxidant alterations. Acute restraint stress (ARS) is known to induce depressive like behavior by neuronal oxidative damage in mice. Swiss albino mice subjected to ARS exhibited an increased immobility time in forced swim test, elevated serum corticosterone and produced oxidative stress dependent alterations in cerebral cortex and hippocampus mainly increased thiobarbituric acid reactive substances and reduced catalase (CAT), superoxide dismutase (SOD) activity. Treatment with PCA was able to prevent stress induced immobility time in forced swim test without altering locomotor activity in mice. Further, PCA treatment attenuated the elevation of serum corticosterone, lipid peroxidation and restored enzymatic antioxidants in cerebral cortex and hippocampus in ARS mice. Altogether, the experimental findings demonstrate the notion that PCA exhibit antidepressant like activity might be related, at least in part, to its capability of modulating antioxidant defense system and oxidative damage induced by ARS in cerebral cortex and hippocampus in mice and thus maintain the pro-/anti-oxidative homeostasis.

Enhanced catalyst activity by decorating of Au on Ag@Cu2O nanoshell

NASA Astrophysics Data System (ADS)

Chen, Lei; Liu, Maomao; Zhao, Yue; Kou, Qiangwei; Wang, Yaxin; Liu, Yang; Zhang, Yongjun; Yang, Jinghai; Jung, Young Mee

2018-03-01

We successfully synthesized Au-decorated Ag@Cu2O heterostructures via a simple galvanic replacement method. As the Au precursor concentration increased, the density of the Au nanoparticles (NPs) on the Ag@Cu2O surface increased, which changed the catalytic activity of the Ag@Cu2O-Au structure. The combination of Au, Ag, and Cu2O exhibited excellent catalytic properties, which can further effect on the catalyst activity of the Ag@Cu2O-Au structure. In addition, the proposed Ag@Cu2O-Au nanocomposite was used to transform the organic, toxic pollutant, 4-nitrophenol (4-NP), into its nontoxic and medicinally important amino derivative via a catalytic reduction to optimize the material performance. The proposed Au-decorated Ag@Cu2O exhibited excellent catalytic activity, and the catalytic reduction time greatly decreased (5 min). Thus, three novel properties of Ag@Cu2O-Au, i.e., charge redistribution and transfer, adsorption, and catalytic reduction of organic pollutants, were ascertained for water remediation. The proposed catalytic properties have potential applications for photocatalysis and localized surface plasmon resonance (LSPR)- and peroxidase-like catalysis.

RESPIRATORY MODULATION OF LINGUAL MUSCLE ACTIVITY ACROSS SLEEP-WAKE STATES IN RATS

PubMed Central

Stettner, Georg M.; Rukhadze, Irma; Mann, Graziella L.; Lei, Yanlin; Kubin, Leszek

2013-01-01

In obstructive sleep apnea (OSA) patients, inspiratory activation (IA) of lingual muscles protects the upper airway from collapse. We aimed to determine when rats’ lingual muscles exhibit IA. In 5 Sprague-Dawley and 3 Wistar rats, we monitored cortical EEG and lingual, diaphragmatic and nuchal electromyograms (EMGs), and identified segments of records when lingual EMG exhibited IA. Individual segments lasted 2.4–269 s (median: 14.5 s), most (89%) occurred during slow-wave sleep (SWS), and they collectively occupied 0.3–6.1% of the total recording time. IA usually started to increase with a delay after SWS onset and ended with an arousal, or declined prior to rapid eye movement sleep. IA of lingual EMG was not accompanied by increased diaphragmatic activity or respiratory rate changes, but occurred when cortical EEG power was particularly low in a low beta-1 frequency range (12.5–16.4 Hz). A deep SWS-related activation of upper airway muscles may be an endogenous phenomenon designed to protect the upper airway against collapse. PMID:23732510

EEG and ocular correlates of circadian melatonin phase and human performance decrements during sleep loss

NASA Technical Reports Server (NTRS)

Cajochen, C.; Khalsa, S. B.; Wyatt, J. K.; Czeisler, C. A.; Dijk, D. J.

1999-01-01

The aim of this study was to quantify the associations between slow eye movements (SEMs), eye blink rate, waking electroencephalogram (EEG) power density, neurobehavioral performance, and the circadian rhythm of plasma melatonin in a cohort of 10 healthy men during up to 32 h of sustained wakefulness. The time course of neurobehavioral performance was characterized by fairly stable levels throughout the first 16 h of wakefulness followed by deterioration during the phase of melatonin secretion. This deterioration was closely associated with an increase in SEMs. Frontal low-frequency EEG activity (1-7 Hz) exhibited a prominent increase with time awake and little circadian modulation. EEG alpha activity exhibited circadian modulation. The dynamics of SEMs and EEG activity were phase locked to changes in neurobehavioral performance and lagged the plasma melatonin rhythm. The data indicate that frontal areas of the brain are more susceptible to sleep loss than occipital areas. Frontal EEG activity and ocular parameters may be used to monitor and predict changes in neurobehavioral performance associated with sleep loss and circadian misalignment.

Microfluidic rheology of active particle suspensions: Kinetic theory

NASA Astrophysics Data System (ADS)

Alonso-Matilla, Roberto; Ezhilan, Barath; Saintillan, David

2016-11-01

We analyze the effective rheology of a dilute suspension of self-propelled slender particles between two infinite parallel plates in a pressure-driven flow. We use a continuum kinetic model to study the dynamics and transport of particles, where hydrodynamic interactions induced by the swimmers are taken into account. Using finite volume simulations we study how the activity of the swimmer and the external flow modify the rheological properties of the system. Results indicate that at low flow rates, activity decreases the value of the viscosity for pushers and increases its value for pullers. Both effects become weaker with increasing the flow strength due to the alignment of the particles with the flow. In the case of puller particles, shear thinning is observed over the entire range of flow rates. Pusher particles exhibit shear thickening at intermediate flow rates, where passive stresses start dominating over active stresses, reaching a viscosity greater than that of the Newtonian fluid. Finally shear thinning is observed at high flow rates. Both pushers and pullers exhibit a Newtonian plateau at very high flow rates. We demonstrate a good agreement between numerical results and experiments.

Physical, Predictive Glycaemic Response and Antioxidative Properties of Black Ear Mushroom (Auricularia auricula) Extrudates.

PubMed

Vallée, Margaux; Lu, Xikun; Narciso, Joan Oñate; Li, Wenhui; Qin, Yuyue; Brennan, Margaret A; Brennan, Charles S

2017-09-01

Black ear mushroom (Auricularia auricula) is an important genus of cultivated mushroom, which contains health benefits. Incorporating black ear (BE) mushroom into brown rice by extrusion changed the physicochemical, and more importantly, the nutritional characteristics of the extrudates. With increased incorporation of BE mushroom in the extrudates in vitro starch digestion of the different extrudates revealed significantly reduced starch digestion, suggesting a lower glycaemic index. In addition, incorporation of BE in brown rice extrudates increased the total phenolic concentration of the samples, which led to higher % scavenging effect against free-radicals in DPPH assay. In the ORAC assay for anti-oxidant activity, BE powder exhibited the highest anti-oxidant activity, followed by 10% BE and 15% BE, and 5% BE extruded products. The extruded brown rice control exhibited the lowest antioxidant activity. Inclusion of black ear mushroom was shown to improve the nutritional qualities of the food product illustrating the connection between plant bioactive ingredients and human health.

Towards efficient and cost-effective inverted hybrid organic solar cells using inorganic semiconductor in the active layer

NASA Astrophysics Data System (ADS)

Imran, M.; Ikram, M.; Dilpazir, S.; Nafees, M.; Ali, S.; Geng, J.

2017-11-01

The article investigates the effects of NiO (p-type) and TiO2 (n-type) nanoparticles (NPs) on the performance of poly(3-hexylthiophene) (P3HT) and (phenyl-C61-butyric acid methylester) (PCBM) based devices with an inverse geometry. Various weight ratios of these nanoparticles were mixed in the polymer solution using 1,2-dichlorobenzene as solvent. An optimal amount of NPs-doped active layer exhibited higher power conversion efficiency (PCE) of 3.85% as compared to the reference cell, which exhibited an efficiency of 3.40% under white light illumination intensity of 100 mW/cm2. Enhanced PCE originates from increased film roughness and light harvesting due to increased absorption range upon mixing an optimal amount of NPs in the organic-based active layer. Further addition of NiO and TiO2 concentration relative to PCBM resulted in significant agglomeration of nanoparticles leading to degraded device parameters.

p53 downregulates the Fanconi anaemia DNA repair pathway

PubMed Central

Jaber, Sara; Toufektchan, Eléonore; Lejour, Vincent; Bardot, Boris; Toledo, Franck

2016-01-01

Germline mutations affecting telomere maintenance or DNA repair may, respectively, cause dyskeratosis congenita or Fanconi anaemia, two clinically related bone marrow failure syndromes. Mice expressing p53Δ31, a mutant p53 lacking the C terminus, model dyskeratosis congenita. Accordingly, the increased p53 activity in p53Δ31/Δ31 fibroblasts correlated with a decreased expression of 4 genes implicated in telomere syndromes. Here we show that these cells exhibit decreased mRNA levels for additional genes contributing to telomere metabolism, but also, surprisingly, for 12 genes mutated in Fanconi anaemia. Furthermore, p53Δ31/Δ31 fibroblasts exhibit a reduced capacity to repair DNA interstrand crosslinks, a typical feature of Fanconi anaemia cells. Importantly, the p53-dependent downregulation of Fanc genes is largely conserved in human cells. Defective DNA repair is known to activate p53, but our results indicate that, conversely, an increased p53 activity may attenuate the Fanconi anaemia DNA repair pathway, defining a positive regulatory feedback loop. PMID:27033104

p53 downregulates the Fanconi anaemia DNA repair pathway.

PubMed

Jaber, Sara; Toufektchan, Eléonore; Lejour, Vincent; Bardot, Boris; Toledo, Franck

2016-04-01

Germline mutations affecting telomere maintenance or DNA repair may, respectively, cause dyskeratosis congenita or Fanconi anaemia, two clinically related bone marrow failure syndromes. Mice expressing p53(Δ31), a mutant p53 lacking the C terminus, model dyskeratosis congenita. Accordingly, the increased p53 activity in p53(Δ31/Δ31) fibroblasts correlated with a decreased expression of 4 genes implicated in telomere syndromes. Here we show that these cells exhibit decreased mRNA levels for additional genes contributing to telomere metabolism, but also, surprisingly, for 12 genes mutated in Fanconi anaemia. Furthermore, p53(Δ31/Δ31) fibroblasts exhibit a reduced capacity to repair DNA interstrand crosslinks, a typical feature of Fanconi anaemia cells. Importantly, the p53-dependent downregulation of Fanc genes is largely conserved in human cells. Defective DNA repair is known to activate p53, but our results indicate that, conversely, an increased p53 activity may attenuate the Fanconi anaemia DNA repair pathway, defining a positive regulatory feedback loop.

The antiaging activity and cerebral protection of rapamycin at micro-doses.

PubMed

Qi, Haiyan; Su, Feng-Yun; Wan, Shan; Chen, Yongjie; Cheng, Yan-Qiong; Liu, Ai-Jun

2014-11-01

The immunosuppressant drug rapamycin was reported to have an antiaging activity, which was attributed to the TORC1 inhibition that inhibits cell proliferation and increases autophagy. However, rapamycin also exhibits a number of harmful adverse effects. Whether rapamycin can be developed into an antiaging agent remains unclear. We demonstrated that rapamycin at micro-doses (below the TORC1 inhibiting concentration) exhibits a cell-protective activity: (1) It protects cultured neurons against neurotoxin MPP(+) and H2O2. (2) It increases survival time of neuron in culture. (3) It maintains the nonproliferative state of cultured senescent human fibroblasts and prevents cell death induced by telomere dysfunction. (4) In animal models, it decreased the cerebral infarct sizes induced by acute ischemia and dramatically extended the life span of stroke prone spontaneously hypertensive rats (SHR-SPs). We propose that rapamycin at micro-dose can be developed into an antiaging agent with a novel mechanism. © 2014 John Wiley & Sons Ltd.

Less efficient and costly processes of frontal cortex in childhood chronic fatigue syndrome.

PubMed

Mizuno, Kei; Tanaka, Masaaki; Tanabe, Hiroki C; Joudoi, Takako; Kawatani, Junko; Shigihara, Yoshihito; Tomoda, Akemi; Miike, Teruhisa; Imai-Matsumura, Kyoko; Sadato, Norihiro; Watanabe, Yasuyoshi

2015-01-01

The ability to divide one's attention deteriorates in patients with childhood chronic fatigue syndrome (CCFS). We conducted a study using a dual verbal task to assess allocation of attentional resources to two simultaneous activities (picking out vowels and reading for story comprehension) and functional magnetic resonance imaging. Patients exhibited a much larger area of activation, recruiting additional frontal areas. The right middle frontal gyrus (MFG), which is included in the dorsolateral prefrontal cortex, of CCFS patients was specifically activated in both the single and dual tasks; this activation level was positively correlated with motivation scores for the tasks and accuracy of story comprehension. In addition, in patients, the dorsal anterior cingulate gyrus (dACC) and left MFG were activated only in the dual task, and activation levels of the dACC and left MFG were positively associated with the motivation and fatigue scores, respectively. Patients with CCFS exhibited a wider area of activated frontal regions related to attentional resources in order to increase their poorer task performance with massive mental effort. This is likely to be less efficient and costly in terms of energy requirements. It seems to be related to the pathophysiology of patients with CCFS and to cause a vicious cycle of further increases in fatigue.

Less efficient and costly processes of frontal cortex in childhood chronic fatigue syndrome

PubMed Central

Mizuno, Kei; Tanaka, Masaaki; Tanabe, Hiroki C.; Joudoi, Takako; Kawatani, Junko; Shigihara, Yoshihito; Tomoda, Akemi; Miike, Teruhisa; Imai-Matsumura, Kyoko; Sadato, Norihiro; Watanabe, Yasuyoshi

2015-01-01

The ability to divide one's attention deteriorates in patients with childhood chronic fatigue syndrome (CCFS). We conducted a study using a dual verbal task to assess allocation of attentional resources to two simultaneous activities (picking out vowels and reading for story comprehension) and functional magnetic resonance imaging. Patients exhibited a much larger area of activation, recruiting additional frontal areas. The right middle frontal gyrus (MFG), which is included in the dorsolateral prefrontal cortex, of CCFS patients was specifically activated in both the single and dual tasks; this activation level was positively correlated with motivation scores for the tasks and accuracy of story comprehension. In addition, in patients, the dorsal anterior cingulate gyrus (dACC) and left MFG were activated only in the dual task, and activation levels of the dACC and left MFG were positively associated with the motivation and fatigue scores, respectively. Patients with CCFS exhibited a wider area of activated frontal regions related to attentional resources in order to increase their poorer task performance with massive mental effort. This is likely to be less efficient and costly in terms of energy requirements. It seems to be related to the pathophysiology of patients with CCFS and to cause a vicious cycle of further increases in fatigue. PMID:26594619

5-Nitroimidazole-derived Schiff bases and their copper(II) complexes exhibit potent antimicrobial activity against pathogenic anaerobic bacteria.

PubMed

Oliveira, Alexandre A; Oliveira, Ana P A; Franco, Lucas L; Ferencs, Micael O; Ferreira, João F G; Bachi, Sofia M P S; Speziali, Nivaldo L; Farias, Luiz M; Magalhães, Paula P; Beraldo, Heloisa

2018-05-07

In the present work a family of novel secnidazole-derived Schiff base compounds and their copper(II) complexes were synthesized. The antimicrobial activities of the compounds were evaluated against clinically important anaerobic bacterial strains. The compounds exhibited in vitro antibacterial activity against Bacteroides fragilis, Bacteroides thetaiotaomicron, Bacteroides vulgatus, Bacteroides ovatus, Parabacteroides distasonis and Fusubacterium nucleatum pathogenic anaerobic bacteria. Upon coordination to copper(II) the antibacterial activity significantly increased in several cases. Some derivatives were even more active than the antimicrobial drugs secnidazole and metronidazole. Therefore, the compounds under study are suitable for in vivo evaluation and the microorganisms should be classified as susceptible to them. Electrochemical studies on the reduction of the nitro group revealed that the compounds show comparable reduction potentials, which are in the same range of the bio-reducible drugs secnidazole and benznidazole. The nitro group reduction potential is more favorable for the copper(II) complexes than for the starting ligands. Hence, the antimicrobial activities of the compounds under study might in part be related to intracellular bio-reduction activation. Considering the increasing resistance rates of anaerobic bacteria against a wide range of antimicrobial drugs, the present work constitutes an important contribution to the development of new antibacterial drug candidates.

Long commuting time, extensive overtime, and sympathodominant state assessed in terms of short-term heart rate variability among male white-collar workers in the Tokyo megalopolis.

PubMed

Kageyama, T; Nishikido, N; Kobayashi, T; Kurokawa, Y; Kaneko, T; Kabuto, M

1998-07-01

To investigate the possible effects of long commuting time and extensive overtime on daytime cardiac autonomic activity, the short-term heart rate variability (HRV) both at supine rest and at standing rest of 223 male white-collar workers in the Tokyo Megalopolis was examined. Workers with a one-way commute of 90 min or more exhibited decreased vagal activity at supine rest and increased sympathetic activity regardless of posture, and those doing overtime of 60 h/month or more exhibited decreased vagal activity and increased sympathetic activity at standing rest. These findings suggest that chronic stress or fatigue resulting from long commuting time or extensive overtime caused these individuals to be in a sympathodominant state. Although these shifts in autonomic activities are not direct indicators of disease, it can be hypothesized that they can induce cardiovascular abnormalities or dysfunctions related to the onset of heart disease. Assessment of the daily and weekly variations in HRV as a function of daily life activities (such as working, commuting, sleeping, and exercising) among workers in Asia-Pacific urban areas might be one way of studying the possible effects of long commuting time, and extensive overtime, on health.

Osteopontin Signals through Calcium and Nuclear Factor of Activated T Cells (NFAT) in Osteoclasts

PubMed Central

Tanabe, Natsuko; Wheal, Benjamin D.; Kwon, Jiyun; Chen, Hong H.; Shugg, Ryan P. P.; Sims, Stephen M.; Goldberg, Harvey A.; Dixon, S. Jeffrey

2011-01-01

Osteopontin (OPN), an integrin-binding extracellular matrix glycoprotein, enhances osteoclast activity; however, its mechanisms of action are elusive. The Ca2+-dependent transcription factor NFATc1 is essential for osteoclast differentiation. We assessed the effects of OPN on NFATc1, which translocates to nuclei upon activation. Osteoclasts from neonatal rabbits and rats were plated on coverslips, uncoated or coated with OPN or bovine albumin. OPN enhanced the proportion of osteoclasts exhibiting nuclear NFATc1. An RGD-containing, integrin-blocking peptide prevented the translocation of NFATc1 induced by OPN. Moreover, mutant OPN lacking RGD failed to induce translocation of NFATc1. Thus, activation of NFATc1 is dependent on integrin binding through RGD. Using fluorescence imaging, OPN was found to increase the proportion of osteoclasts exhibiting transient elevations in cytosolic Ca2+ (oscillations). OPN also enhanced osteoclast survival. The intracellular Ca2+ chelator 1,2-bis(O-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid (BAPTA) suppressed Ca2+ oscillations and inhibited increases in NFATc1 translocation and survival induced by OPN. Furthermore, a specific, cell-permeable peptide inhibitor of NFAT activation blocked the effects of OPN on NFATc1 translocation and osteoclast survival. This is the first demonstration that OPN activates NFATc1 and enhances osteoclast survival through a Ca2+-NFAT-dependent pathway. Increased NFATc1 activity and enhanced osteoclast survival may account for the stimulatory effects of OPN on osteoclast function in vivo. PMID:21940634

Piracetam Facilitates the Anti-Amnesic but not Anti-Diabetic Activity of Metformin in Experimentally Induced Type-2 Diabetic Encephalopathic Rats.

PubMed

Pandey, Shruti; Garabadu, Debapriya

2017-07-01

Piracetam exhibits anti-amnesic activity in several animal models of dementia. However, its anti-amnesic potential has yet to be evaluated in type-2 diabetes mellitus (T2DM)-induced encephalopathy. Therefore, in the present study, piracetam (25, 50 and 100 mg/kg) was screened for anti-amnesic and anti-diabetic activity in T2DM-induced encephalopathic male rats. Subsequently, anti-amnesic and anti-diabetic activities were evaluated for piracetam, metformin and their combination in T2DM-induced encephalopathic animals. Rats received streptozotocin (45 mg/kg) and nicotinamide (110 mg/kg) injections on day-1 (D-1) of the experimental schedule and were kept undisturbed for 35 days to exhibit T2DM-induced encephalopathy. All drug treatments were continued from D-7 to D-35 in both experiments. Piracetam (100 mg/kg) attenuated loss in learning and memory in terms of increase in escape latency on D-4 (D-34) and decrease in time spent in the target quadrant on D-5 (D-35) of Morris water maze test protocol, and spatial memory in terms of reduced spontaneous alternation behavior in Y-maze test of encephalopathic rats. Additionally, piracetam attenuated altered levels of fasting plasma glucose and insulin, HOMA-IR and HOMA-B in encephalopathic animals, comparatively lesser than metformin. In the next experiment, combination of piracetam and metformin exhibited better anti-amnesic but not anti-diabetic activity than respective monotherapies in encephalopathic rats. Further, the combination attenuated reduced acetylcholine level and increased acetylcholinesterase activity, increased glycogen synthase kinase-3β level and decreased brain-derived neurotropic factor level in hippocampus and pre-frontal cortex of encephalopathic animals. Thus, piracetam could be used as an adjuvant to metformin in the management of dementia in T2DM-induced encephalopathy.

Nutritional history does not modulate hepatic oxidative status of European sea bass (Dicentrarchus labrax) submitted to handling stress.

PubMed

Castro, Carolina; Peréz-Jiménez, Amalia; Coutinho, Filipe; Corraze, Geneviève; Panserat, Stéphane; Peres, Helena; Teles, Aires Oliva; Enes, Paula

2018-06-01

The aim of the present study was to assess the impact of an acute handling stress on hepatic oxidative status of European sea bass (Dicentrarchus labrax) juveniles fed diets differing in lipid so urce and carbohydrate content. For that purpose, four diets were formulated with fish oil (FO) and vegetable oils (VO) as lipid source and with 20 or 0% gelatinized starch as carbohydrate source. Triplicate groups of fish with 74 g were fed each diet during 13 weeks and then subjected to an acute handling stress. Stress exposure decreased hematocrit (Ht) and hemoglobin (Hb) levels. Independent of dietary treatment, stress exposure increased hepatic lipid peroxidation (LPO). Stressed fish exhibited lower glucose 6-phosphate dehydrogenase (G6PD), catalase (CAT), and superoxide dismutase (SOD) activities, independent of previous nutritional history. In the VO groups, stress exposure increased glutathione peroxidase (GPX) activity. Diet composition had no effect on Ht and Hb levels. In contrast, dietary carbohydrate decreased hepatic LPO and CAT activity and increased glutathione reductase (GR) and G6PD activities. Dietary lipids had no effect on LPO. Fish fed the VO diets exhibited higher G6PD activity than fish fed the FO diets. In conclusion, dietary carbohydrates contributed to the reduction of oxidative stress in fish. However, under the imposed handling stress conditions, liver enzymatic antioxidant mechanisms were not enhanced, which may explain the overall increased oxidative stress.

Elevated extracellular glucose and uncontrolled type 1 diabetes enhance NFAT5 signaling and disrupt the transverse tubular network in mouse skeletal muscle

PubMed Central

Hernández-Ochoa, Erick O; Robison, Patrick; Contreras, Minerva; Shen, Tiansheng; Zhao, Zhiyong; Schneider, Martin F

2012-01-01

The transcription factor nuclear factor of activated T-cells 5 (NFAT5) is a key protector from hypertonic stress in the kidney, but its role in skeletal muscle is unexamined. Here, we evaluate the effects of glucose hypertonicity and hyperglycemia on endogenous NFAT5 activity, transverse tubular system morphology and Ca2+ signaling in adult murine skeletal muscle fibers. We found that exposure to elevated glucose (25–50 mmol/L) increased NFAT5 expression and nuclear translocation, and NFAT-driven transcriptional activity. These effects were insensitive to the inhibition of calcineurin A, but sensitive to both p38a mitogen-activated protein kinases and phosphoinositide 3-kinase-related kinase inhibition. Fibers exposed to elevated glucose exhibited disrupted transverse tubular morphology, characterized by swollen transverse tubules and an increase in longitudinal connections between adjacent transverse tubules. Ca2+ transients elicited by a single, brief electric field stimuli were increased in amplitude in fibers challenged by elevated glucose. Muscle fibers from type 1 diabetic mice exhibited increased NFAT5 expression and transverse tubule disruptions, but no differences in electrically evoked Ca2+ transients. Our results suggest the hypothesis that these changes in skeletal muscle could play a role in the pathophysiology of acute and severe hyperglycemic episodes commonly observed in uncontrolled diabetes. PMID:22966145

Reduced African Easterly Wave Activity with Quadrupled CO 2 in the Superparameterized CESM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hannah, Walter M.; Aiyyer, Anantha

African easterly wave (AEW) activity is examined in quadrupled CO 2 experiments with the superparameterized CESM (SP-CESM). The variance of 2–10-day filtered precipitation increases with warming over the West African monsoon region, suggesting increased AEW activity. The perturbation enstrophy budget is used to investigate the dynamic signature of AEW activity. The northern wave track becomes more active associated with enhanced baroclinicity, consistent with previous studies. The southern track exhibits a surprising reduction of wave activity associated with less frequent occurrence of weak waves and a slight increase in the occurrence of strong waves. These changes are connected to changes inmore » the profile of vortex stretching and tilting that can be understood as interconnected consequences of increased static stability from the lapse rate response, weak temperature gradient balance, and the fixed anvil temperature hypothesis.« less

Reduced African Easterly Wave Activity with Quadrupled CO 2 in the Superparameterized CESM

DOE PAGES

Hannah, Walter M.; Aiyyer, Anantha

2017-10-01

African easterly wave (AEW) activity is examined in quadrupled CO 2 experiments with the superparameterized CESM (SP-CESM). The variance of 2–10-day filtered precipitation increases with warming over the West African monsoon region, suggesting increased AEW activity. The perturbation enstrophy budget is used to investigate the dynamic signature of AEW activity. The northern wave track becomes more active associated with enhanced baroclinicity, consistent with previous studies. The southern track exhibits a surprising reduction of wave activity associated with less frequent occurrence of weak waves and a slight increase in the occurrence of strong waves. These changes are connected to changes inmore » the profile of vortex stretching and tilting that can be understood as interconnected consequences of increased static stability from the lapse rate response, weak temperature gradient balance, and the fixed anvil temperature hypothesis.« less

Eye shape and the nocturnal bottleneck of mammals.

PubMed

Hall, Margaret I; Kamilar, Jason M; Kirk, E Christopher

2012-12-22

Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal 'bottleneck' in the early evolution of crown mammals.

Antioxidant Properties and Cardioprotective Mechanism of Malaysian Propolis in Rats.

PubMed

Ahmed, Romana; Tanvir, E M; Hossen, Md Sakib; Afroz, Rizwana; Ahmmed, Istiyak; Rumpa, Nur-E-Noushin; Paul, Sudip; Gan, Siew Hua; Sulaiman, Siti Amrah; Khalil, Md Ibrahim

2017-01-01

Propolis contains high concentrations of polyphenols, flavonoids, tannins, ascorbic acid, and reducing sugars and proteins. Malaysian Propolis (MP) has been reported to exhibit high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and ferric reducing antioxidant power (FRAP) values. Herein, we report the antioxidant properties and cardioprotective properties of MP in isoproterenol- (ISO-) induced myocardial infarction in rats. Male Wistar rats ( n = 32) were pretreated orally with an ethanol extract of MP (100 mg/kg/day) for 30 consecutive days. Subcutaneous injection of ISO (85 mg/kg in saline) for two consecutive days caused a significant increase in serum cardiac marker enzymes and cardiac troponin I levels and altered serum lipid profiles. In addition significantly increased lipid peroxides and decreased activities of cellular antioxidant defense enzymes were observed in the myocardium. However, pretreatment of ischemic rats with MP ameliorated the biochemical parameters, indicating the protective effect of MP against ISO-induced ischemia in rats. Histopathological findings obtained for the myocardium further confirmed the biochemical findings. It is concluded that MP exhibits cardioprotective activity against ISO-induced oxidative stress through its direct cytotoxic radical-scavenging activities. It is also plausible that MP contributed to endogenous antioxidant enzyme activity via inhibition of lipid peroxidation.

Short-term and long-term treatment outcomes with Class III activator

PubMed Central

Ryu, Hyo-kyung; Chong, Hyun-Jeong; An, Ki-Yong

2015-01-01

Objective The purpose of this retrospective study was to investigate short-term and long-term skeletodental outcomes of Class III activator treatment. Methods A Class III activator treatment group (AG) comprised of 22 patients (9 boys, 13 girls) was compared with a Class III control group (CG) comprised of 17 patients (6 boys, 11 girls). The total treatment period was divided into three stages; the initial stage (T1), the post-activator treatment or post-mandibular growth peak stage (T2), and the long-term follow-up stage (T3). Cephalometric changes were evaluated statistically via the Mann-Whitney U-test and the Friedman test. Results The AG exhibited significant increases in the SNA angle, ANB angle, Wits appraisal, A point-N perpendicular, Convexity of A point, and proclination of the maxillary incisors, from T1 to T2. In the long-term follow-up (T1-T3), the AG exhibited significantly greater increases in the ANB angle, Wits appraisal, and Convexity of A point than the CG. Conclusions Favorable skeletal outcomes induced during the Class III activator treatment period were generally maintained until the long-term follow-up period of the post-mandibular growth peak stage. PMID:26445717

Eye shape and the nocturnal bottleneck of mammals

PubMed Central

Hall, Margaret I.; Kamilar, Jason M.; Kirk, E. Christopher

2012-01-01

Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal ‘bottleneck’ in the early evolution of crown mammals. PMID:23097513

Dietary menhaden oil contributes to hepatic lipidosis in laying hens.

PubMed

Van Elswyk, M E; Hargis, B M; Williams, J D; Hargis, P S

1994-05-01

Clinical and epidemiological investigations have indicated that there may be substantial human cardiovascular benefits associated with increased consumption of n-3 fatty acids commonly found in fish oils. Recent studies have indicated that egg yolk n-3 fatty acid content is significantly increased when hens are fed diets enriched with selected fish oils such as menhaden oil (MO). In the present study, reproductively active females but not males exhibited increased hepatic lipidosis following 6 mo of feeding 3% MO. Hens fed 3% animal-vegetable oil (AV) did not exhibit hepatic lipid accumulation. Serum triglyceride and cholesterol concentrations were reduced (P < or = .05) in hens fed MO. Subsequently, yolk and total egg weights of hens fed MO were decreased as compared with those of hens fed AV. A significant interaction of dietary MO and exogenous 17 beta-estradiol was noted among chick liver and gallbladder weights. These data suggest that dietary MO and estradiol may interact in a manner that enhances the lipogenic activity of the liver, thereby inducing hepatic lipidosis in laying hens.

Resistance to Degradation and Cellular Distribution are Important Features for the Antitumor Activity of Gomesin

PubMed Central

Buri, Marcus V.; Domingues, Tatiana M.; Paredes-Gamero, Edgar J.; Casaes-Rodrigues, Rafael L.; Rodrigues, Elaine Guadelupe; Miranda, Antonio

2013-01-01

Many reports have shown that antimicrobial peptides exhibit anticancer abilities. Gomesin (Gm) exhibits potent cytotoxic activity against cancer cells by a membrane pore formation induced after well-orchestrated intracellular mechanisms. In this report, the replacements of the Cys by Ser or Thr, and the use D-amino acids in the Gm structure were done to investigate the importance of the resistance to degradation of the molecule with its cytotoxicity. [Thr2,6,11,15]-Gm, and [Ser2,6,11,15]-Gm exhibits low cytotoxicity, and low resistance to degradation, and after 24 h are present in localized area near to the membrane. Conversely, the use of D-amino acids in the analogue [D-Thr2,6,11,15]-D-Gm confers resistance to degradation, increases its potency, and maintained this peptide spread in the cytosol similarly to what happens with Gm. Replacements of Cys by Thr and Gln by L- or D-Pro ([D-Thr2,6,11,15, Pro9]-D-Gm, and [Thr2,6,11,15, D-Pro9]-Gm), which induced a similar β-hairpin conformation, also increase their resistance to degradation, and cytotoxicity, but after 24 h they are not present spread in the cytosol, exhibiting lower cytotoxicity in comparison to Gm. Additionally, chloroquine, a lysosomal enzyme inhibitor potentiated the effect of the peptides. Furthermore, the binding and internalization of peptides was determined, but a direct correlation among these factors was not observed. However, cholesterol ablation, which increase fluidity of cellular membrane, also increase cytotoxicity and internalization of peptides. β-hairpin spatial conformation, and intracellular localization/target, and the capability of entry are important properties of gomesin cytotoxicity. PMID:24312251

A longitudinal study of Caenorhabditis elegans larvae reveals a novel locomotion switch, regulated by Gαs signaling

PubMed Central

Nagy, Stanislav; Wright, Charles; Tramm, Nora; Labello, Nicholas; Burov, Stanislav; Biron, David

2013-01-01

Despite their simplicity, longitudinal studies of invertebrate models are rare. We thus sought to characterize behavioral trends of Caenorhabditis elegans, from the mid fourth larval stage through the mid young adult stage. We found that, outside of lethargus, animals exhibited abrupt switching between two distinct behavioral states: active wakefulness and quiet wakefulness. The durations of epochs of active wakefulness exhibited non-Poisson statistics. Increased Gαs signaling stabilized the active wakefulness state before, during and after lethargus. In contrast, decreased Gαs signaling, decreased neuropeptide release, or decreased CREB activity destabilized active wakefulness outside of, but not during, lethargus. Taken together, our findings support a model in which protein kinase A (PKA) stabilizes active wakefulness, at least in part through two of its downstream targets: neuropeptide release and CREB. However, during lethargus, when active wakefulness is strongly suppressed, the native role of PKA signaling in modulating locomotion and quiescence may be minor. DOI: http://dx.doi.org/10.7554/eLife.00782.001 PMID:23840929

Length dependence of force generation exhibit similarities between rat cardiac myocytes and skeletal muscle fibres.

PubMed

Hanft, Laurin M; McDonald, Kerry S

2010-08-01

According to the Frank-Starling relationship, increased ventricular volume increases cardiac output, which helps match cardiac output to peripheral circulatory demand. The cellular basis for this relationship is in large part the myofilament length-tension relationship. Length-tension relationships in maximally calcium activated preparations are relatively shallow and similar between cardiac myocytes and skeletal muscle fibres. During twitch activations length-tension relationships become steeper in both cardiac and skeletal muscle; however, it remains unclear whether length dependence of tension differs between striated muscle cell types during submaximal activations. The purpose of this study was to compare sarcomere length-tension relationships and the sarcomere length dependence of force development between rat skinned left ventricular cardiac myocytes and fast-twitch and slow-twitch skeletal muscle fibres. Muscle cell preparations were calcium activated to yield 50% maximal force, after which isometric force and rate constants (k(tr)) of force development were measured over a range of sarcomere lengths. Myofilament length-tension relationships were considerably steeper in fast-twitch fibres compared to slow-twitch fibres. Interestingly, cardiac myocyte preparations exhibited two populations of length-tension relationships, one steeper than fast-twitch fibres and the other similar to slow-twitch fibres. Moreover, myocytes with shallow length-tension relationships were converted to steeper length-tension relationships by protein kinase A (PKA)-induced myofilament phosphorylation. Sarcomere length-k(tr) relationships were distinct between all three cell types and exhibited patterns markedly different from Ca(2+) activation-dependent k(tr) relationships. Overall, these findings indicate cardiac myocytes exhibit varied length-tension relationships and sarcomere length appears a dominant modulator of force development rates. Importantly, cardiac myocyte length-tension relationships appear able to switch between slow-twitch-like and fast-twitch-like by PKA-mediated myofibrillar phosphorylation, which implicates a novel means for controlling Frank-Starling relationships.

(2S,4S)-4-Fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}-pyrrolidine-2-carbonitrile monobenzenesulfonate (TS-021) is a selective and reversible dipeptidyl peptidase IV inhibitor.

PubMed

Tajima, Atsushi; Yamamoto, Koji; Kozakai, Akinori; Okumura-Kitajima, Lisa; Mita, Yasuo; Kitano, Kiyokazu; Jingu, Shigeji; Nakaike, Shiro

2011-03-25

The incretin hormone glucagon-like peptide-1 (GLP-1) has significant roles in the regulation of postprandial glucose metabolism, and the active form of GLP-1 is rapidly degraded by dipeptidyl peptidase (DPP)-IV. Therefore, DPP-IV inhibition is a promising approach for the treatment of type 2 diabetes. In the present study, we investigated the character of a DPP-IV inhibitor, TS-021, (2S, 4S)-4-fluoro-1-{[(2-hydroxy-1,1-dimethylethyl)amino]acetyl}-pyrrolidine-2-carbonitrile monobenzenesulfonate both in vitro and in vivo. TS-021 inhibits DPP-IV activity in human plasma with an IC(50) value of 5.34nM. In kinetics experiments, TS-021 had a relatively higher dissociation rate constant, with a k(off) value of 1.09×10(-3)s, despite exhibiting a potent human plasma DPP-IV inhibition activity with a K(i) value of 4.96nM. TS-021 exhibited significant inhibition selectivity against DPP-8 (>600 fold), DPP-9 (>1200 fold) and other peptidases examined (>15,000 fold). In normal rats, dogs and monkeys, a single oral dose of TS-021 exhibited favorable pharmacokinetic profiles. In Zucker fatty (fa/fa) rats, a rat model of obesity and impaired glucose tolerance, the oral administration of TS-021 resulted in the suppression of plasma DPP-IV activity and an increase in the active form of GLP-1. Furthermore, TS-021 exhibited a significant improvement in glucose tolerance by increasing the plasma insulin level during oral glucose tolerance tests at doses of 0.02-0.5mg/kg. These results suggest that TS-021 is a selective and reversible dipeptidyl peptidase IV inhibitor and has excellent characteristics as an oral anti-diabetic agent for postprandial hyperglycemia in patients with impaired glucose tolerance or type 2 diabetes. Copyright © 2011 Elsevier B.V. All rights reserved.

Quantitative assessment of the impacts of climate change and human activities on runoff change in a typical karst watershed, SW China.

PubMed

Wu, Luhua; Wang, Shijie; Bai, Xiaoyong; Luo, Weijun; Tian, Yichao; Zeng, Cheng; Luo, Guangjie; He, Shiyan

2017-12-01

The Yinjiang River watershed is a typical karst watershed in Southwest China. The present study explored runoff change and its responses to different driving factors in the Yinjiang River watershed over the period of 1984 to 2015. The methods of cumulative anomaly, continuous wavelet analysis, Mann-Kendall rank correlation trend test, and Hurst exponent were applied to analyze the impacts of climate change and human activities on runoff change. The contributions of climate change and human activities to runoff change were quantitatively assessed using the comparative method of the slope changing ratio of cumulative quantity (SCRCQ). The following results were obtained: (1) From 1984 to 2015, runoff and precipitation exhibited no-significant increasing trend, whereas evaporation exhibited significant decreasing trend. (2) In the future, runoff, precipitation, and evaporation will exhibit weak anti-persistent feature with different persistent times. This feature indicated that in their persistent times, runoff and precipitation will continuously decline, whereas evaporation will continuously increase. (3) Runoff and precipitation were well-synchronized with abrupt change features and stage characteristics, and exhibited consistent multi-timescale characteristics that were different from that of evaporation. (4) The contribution of precipitation to runoff change was 50%-60% and was considered high and stable. The contribution of evaporation to runoff change was 10%-90% and was variable with a positive or negative effects. The contribution of human activities to runoff change was 20%-60% and exerted a low positive or negative effect. (5) Climatic factors highly contributed to runoff change. By contrast, the contribution of human activities to runoff change was low. The contribution of climatic factors to runoff change was highly variable because of differences among base periods. In conclusion, this paper provides a basic theoretical understanding of the main factors that contribute to runoff change in a karst watershed. Copyright © 2017 Elsevier B.V. All rights reserved.

Dicarboxylic acid transport in Bradyrhizobium japonicum: use of Rhizobium meliloti dct gene(s) to enhance nitrogen fixation.

PubMed Central

Birkenhead, K; Manian, S S; O'Gara, F

1988-01-01

A recombinant plasmid encoding Rhizobium meliloti sequences involved in dicarboxylic acid transport (plasmid pRK290:4:46) (E. Bolton, B. Higgisson, A. Harrington, and F. O'Gara, Arch. Microbiol. 144:142-146, 1986) was used to study the relationship between dicarboxylic acid transport and nitrogen fixation in Bradyrhizobium japonicum. The expression of the dct sequences on plasmid pRK290:4:46 in B. japonicum CJ1 resulted in increased growth rates in media containing dicarboxylic acids as the sole source of carbon. In addition, strain CJ1(pRK290:4:46) exhibited enhanced succinate uptake activity when grown on dicarboxylic acids under aerobic conditions. Under free-living nitrogen-fixing conditions, strain CJ1(pRK290:4:46) exhibited higher nitrogenase (acetylene reduction) activity compared with that of the wild-type strain. This increase in nitrogenase activity also correlated with an enhanced dicarboxylic acid uptake rate under these microaerobic conditions. The regulation of dicarboxylic acid transport by factors such as metabolic inhibitors and the presence of additional carbon sources was similar in both the wild-type and the engineered strains. The implications of increasing nitrogenase activity through alterations in the dicarboxylic acid transport system are discussed. PMID:3422072

Tellurite-exposed Escherichia coli exhibits increased intracellular {alpha}-ketoglutarate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reinoso, Claudia A.; Auger, Christopher; Appanna, Vasu D.

2012-05-18

Highlights: Black-Right-Pointing-Pointer Tellurite-exposed E. coli exhibits decreased {alpha}-KG dehydrogenase activity. Black-Right-Pointing-Pointer Cells lacking {alpha}-KGDH genes are more sensitive to ROS than isogenic, wt E. coli. Black-Right-Pointing-Pointer KG accumulation may serve to face tellurite-mediated oxidative damage in E. coli. -- Abstract: The tellurium oxyanion tellurite is toxic to most organisms because of its ability to generate oxidative stress. However, the detailed mechanism(s) how this toxicant interferes with cellular processes have yet to be fully understood. As part of our effort to decipher the molecular interactions of tellurite with living systems, we have evaluated the global metabolism of {alpha}-ketoglutarate a known antioxidantmore » in Escherichia coli. Tellurite-exposed cells displayed reduced activity of the KG dehydrogenase complex (KGDHc), resulting in increased intracellular KG content. This complex's reduced activity seems to be due to decreased transcription in the stressed cells of sucA, a gene that encodes the E1 component of KGDHc. Furthermore, it was demonstrated that the increase in total reactive oxygen species and superoxide observed upon tellurite exposure was more evident in wild type cells than in E. coli with impaired KGDHc activity. These results indicate that KG may be playing a pivotal role in combating tellurite-mediated oxidative damage.« less

Rheb/mTORC1 Signaling Promotes Kidney Fibroblast Activation and Fibrosis

PubMed Central

Jiang, Lei; Xu, Lingling; Mao, Junhua; Li, Jianzhong; Fang, Li; Zhou, Yang; Liu, Wei; He, Weichun; Zhao, Allan Zijian

2013-01-01

Ras homolog enriched in brain (Rheb) is a small GTPase that regulates cell growth, differentiation, and survival by upregulating mammalian target of rapamycin complex 1 (mTORC1) signaling. The role of Rheb/mTORC1 signaling in the activation of kidney fibroblasts and the development of kidney fibrosis remains largely unknown. In this study, we found that Rheb/mTORC1 signaling was activated in interstitial myofibroblasts from fibrotic kidneys. Treatment of rat kidney interstitial fibroblasts (NRK-49F cell line) with TGFβ1 also activated Rheb/mTORC1 signaling. Blocking Rheb/mTORC1 signaling with rapamycin or Rheb small interfering RNA abolished TGFβ1-induced fibroblast activation. In a transgenic mouse, ectopic expression of Rheb activated kidney fibroblasts. These Rheb transgenic mice exhibited increased activation of mTORC1 signaling in both kidney tubular and interstitial cells as well as progressive interstitial renal fibrosis; rapamycin inhibited these effects. Similarly, mice with fibroblast-specific deletion of Tsc1, a negative regulator of Rheb, exhibited activated mTORC1 signaling in kidney interstitial fibroblasts and increased renal fibrosis, both of which rapamycin abolished. Taken together, these results suggest that Rheb/mTORC1 signaling promotes the activation of kidney fibroblasts and contributes to the development of interstitial fibrosis, possibly providing a therapeutic target for progressive renal disease. PMID:23661807

Spermine and spermidine act as chemical chaperones and enhance chaperone-like and membranolytic activities of major bovine seminal plasma protein, PDC-109.

PubMed

Singh, Bhanu Pratap; Saha, Ishita; Nandi, Indrani; Swamy, Musti J

2017-12-02

The major bovine seminal plasma protein, PDC-109, binds to choline phospholipids of the sperm plasma membrane and induces an efflux of cholesterol and choline phospholipids (cholesterol efflux), which is crucial for sperm capacitation. PDC-109 also exhibits chaperone-like activity and protects target proteins against various kinds of stress. Here we show that the polyamines spermine and spermidine, present in high concentration in the seminal plasma of various mammals, increase the ability of PDC-109 to perturb membrane structure as well as its chaperone-like activity. Interestingly, spermine/spermidine alone did not perturb membrane structure but exhibited chaperone-like activity by protecting target proteins against thermal and oxidative stress. When spermine/spermidine was used along with PDC-109, the observed chaperone-like activity was considerably higher than that expected for a simple additive effect, suggesting that PDC-109 and the polyamines act in a synergistic fashion. These results indicate that at the high concentrations present in the seminal plasma spermine/spermidine exhibit a positive modulatory effect on the chaperone-like activity of PDC-109 and may also function as chemical chaperones and protect other seminal plasma proteins from various kinds of stress. Copyright © 2017 Elsevier Inc. All rights reserved.

Distributed patterns of activity in sensory cortex reflect the precision of multiple items maintained in visual short-term memory.

PubMed

Emrich, Stephen M; Riggall, Adam C; Larocque, Joshua J; Postle, Bradley R

2013-04-10

Traditionally, load sensitivity of sustained, elevated activity has been taken as an index of storage for a limited number of items in visual short-term memory (VSTM). Recently, studies have demonstrated that the contents of a single item held in VSTM can be decoded from early visual cortex, despite the fact that these areas do not exhibit elevated, sustained activity. It is unknown, however, whether the patterns of neural activity decoded from sensory cortex change as a function of load, as one would expect from a region storing multiple representations. Here, we use multivoxel pattern analysis to examine the neural representations of VSTM in humans across multiple memory loads. In an important extension of previous findings, our results demonstrate that the contents of VSTM can be decoded from areas that exhibit a transient response to visual stimuli, but not from regions that exhibit elevated, sustained load-sensitive delay-period activity. Moreover, the neural information present in these transiently activated areas decreases significantly with increasing load, indicating load sensitivity of the patterns of activity that support VSTM maintenance. Importantly, the decrease in classification performance as a function of load is correlated with within-subject changes in mnemonic resolution. These findings indicate that distributed patterns of neural activity in putatively sensory visual cortex support the representation and precision of information in VSTM.

Gaze pursuit responses in nucleus reticularis tegmenti pontis of head-unrestrained macaques.

PubMed

Suzuki, David A; Betelak, Kathleen F; Yee, Robert D

2009-01-01

Eye-head gaze pursuit-related activity was recorded in rostral portions of the nucleus reticularis tegmenti pontis (rNRTP) in alert macaques. The head was unrestrained in the horizontal plane, and macaques were trained to pursue a moving target either with their head, with the eyes stationary in the orbits, or with their eyes, with their head voluntarily held stationary in space. Head-pursuit-related modulations in rNRTP activity were observed with some cells exhibiting increases in firing rate with increases in head-pursuit frequency. For many units, this head-pursuit response appeared to saturate at higher frequencies (>0.6 Hz). The response phase re:peak head-pursuit velocity formed a continuum, containing cells that could encode head-pursuit velocity and those encoding head-pursuit acceleration. The latter cells did not exhibit head position-related activity. Sensitivities were calculated with respect to peak head-pursuit velocity and averaged 1.8 spikes/s/deg/s. Of the cells that were tested for both head- and eye-pursuit-related activity, 86% exhibited responses to both head- and eye-pursuit and therefore carried a putative gaze-pursuit signal. For these gaze-pursuit units, the ratio of head to eye response sensitivities averaged approximately 1.4. Pursuit eccentricity seemed to affect head-pursuit response amplitude even in the absence of a head position response per se. The results indicated that rNRTP is a strong candidate for the source of an active head-pursuit signal that projects to the cerebellum, specifically to the target-velocity and gaze-velocity Purkinje cells that have been observed in vermal lobules VI and VII.

In vitro evaluation of cytotoxicity and leishmanicidal activity of phthalimido-thiazole derivatives.

PubMed

Aliança, Amanda Silva Dos Santos; Oliveira, Arsênio Rodrigues; Feitosa, Ana Paula Sampaio; Ribeiro, Karla Raíza Cardoso; de Castro, Maria Carolina Accioly Brelaz; Leite, Ana Cristina Lima; Alves, Luiz Carlos; Brayner, Fábio André

2017-07-15

It is estimated that the worldwide prevalence of leishmaniasis is around 12 million individuals in 80 countries, with 400,000new cases per year. In the search for new leishmanicidal agents, the hybrid phthalimido-thiazoles have been identified as an important scaffold for drug design and discovery. The present study thus reports the in vitro activity of a series of phthalimido-thiazole derivatives. Cytotoxicity against a strain of L. infantum, Vero cells, J774 macrophages and peritoneal macrophages was evaluated, as well as nitric oxide (NO) production. Activity against amastigote and promastigote forms of L. infantum and microscopic changes in the parasite and intracellular targets of the parasite were achieved. The results show that the compounds arising from hybridization of phthalimide and 1,3-thiazole exhibit promising leishmanicidal activity. Compounds 2j and 2m were the most potent of the series tested and the parasites treated with these compounds exhibited ultrastructural changes, such as cell body shrinkage, loss of cellular membrane integrity, vacuolization of cytoplasm, membrane profiles surrounding organelles and swelling of mitochondria. The data showed that these compounds reduced the survival of intracellular amastigotes and presented low toxicity for mammalian cells. The compounds produced increased NO production compared to untreated cells in non-infected macrophages. Treated promastigote forms showed an increase in the number of cells stained with propidium iodide. The compounds brought about significant changes in mitochondrial membrane potential. According to the present study, phthalimido-thiazole compounds exhibit leishmanicidal activity and could be used to develop novel antileishmaniasis drugs and explore potential molecular targets. Copyright © 2017 Elsevier B.V. All rights reserved.

Dielectric behavior and AC conductivity of Cr doped α-Mn2O3

NASA Astrophysics Data System (ADS)

Chandra, Mohit; Yadav, Satish; Singh, K.

2018-05-01

The complex dielectric behavior of polycrystalline α-Mn2-xCrxO3 (x = 0.10) has been investigated isothermally at wide frequency range (4Hz-1 MHz) at different temperatures (300-390K). The dielectric spectroscopy results have been discussed in different formulism like dielectric constant, impedance and ac conductivity. The frequency dependent dielectric loss (tanδ) exhibit a clear relaxation behavior in the studied temperature range. The relaxation frequency increases with increasing temperature. These results are fitted using Arrhenius equation which suggest thermally activated process and the activation energy is 0.173±0.0024 eV. The normalized tanδ curves at different temperatures merge as a single master curve which indicate that the relaxation process follow the similar relaxation dynamics in the studied temperature range. Further, the dielectric relaxation follows non-Debye behavior. The impedance results inference that the grain boundary contribution dominate at lower frequency whereas grain contribution appeared at higher frequencies and exhibit strong temperature dependence. The ac conductivity data shows that the ac conductivity increases with increasing temperature which corroborate the semiconducting nature of the studied sample.

Liver Fatty acid binding protein (L-Fabp) modulates murine stellate cell activation and diet induced nonalcoholic fatty liver disease

PubMed Central

Chen, Anping; Tang, Youcai; Davis, Victoria; Hsu, Fong-Fu; Kennedy, Susan M.; Song, Haowei; Turk, John; Brunt, Elizabeth M.; Newberry, Elizabeth P.; Davidson, Nicholas O.

2013-01-01

Activation of hepatic stellate cells (HSCs) is crucial to the development of fibrosis in nonalcoholic fatty liver disease. Quiescent HSCs contain lipid droplets (LDs), whose depletion upon activation induces a fibrogenic gene program. Here we show that liver fatty acid-binding protein (L-Fabp), an abundant cytosolic protein that modulates fatty acid (FA) metabolism in enterocytes and hepatocytes also modulates HSC FA utilization and in turn regulates the fibrogenic program. L-Fabp expression decreased 10-fold following HSC activation, concomitant with depletion of LDs. Primary HSCs isolated from L-FABP−/− mice contain fewer LDs than wild type (WT) HSCs, and exhibit upregulated expression of genes involved in HSC activation. Adenoviral L-Fabp transduction inhibited activation of passaged WT HSCs and increased both the expression of prolipogenic genes and also augmented intracellular lipid accumulation, including triglyceride and FA, predominantly palmitate. Freshly isolated HSCs from L-FABP−/− mice correspondingly exhibited decreased palmitate in the free FA pool. To investigate whether L-FABP deletion promotes HSC activation in vivo, we fed L-FABP−/− and WT mice a high fat diet supplemented with trans-fatty acids and fructose (TFF). TFF-fed L-FABP−/− mice exhibited reduced hepatic steatosis along with decreased LD abundance and size compared to WT mice. In addition, TFF-fed L-FABP−/− mice exhibited decreased hepatic fibrosis, with reduced expression of fibrogenic genes, compared to WT mice. Conclusion L-FABP deletion attenuates both diet-induced hepatic steatosis and fibrogenesis, despite the observation that L-Fabp paradoxically promotes FA and LD accumulation and inhibits HSC activation in vitro. These findings highlight the importance of cell-specific modulation of hepatic lipid metabolism in promoting fibrogenesis in nonalcoholic fatty liver disease. PMID:23401290

Validation of Autonomic and Endocrine Reactivity to a Laboratory Stressor in Young Children

PubMed Central

Roos, Leslie E.; Giuliano, Ryan J.; Beauchamp, Kathryn G.; Gunnar, Megan; Amidon, Brigette; Fisher, Philip A.

2017-01-01

The validation of laboratory paradigms that reliably induce a stress response [including hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) activation], is critical for understanding how children’s stress-response systems support emotional and cognitive function. Early childhood research to date is markedly limited, given the difficulty in establishing paradigms that reliably induce a cortisol response. Furthermore, research to date has not included a control condition or examined concurrent ANS reactivity. We addressed these limitations by characterizing the extent to which a modified matching task stressor paradigm induces HPA and ANS activation, beyond a closely matched control condition. Modifications include an unfamiliar and unfriendly assessor to increase the stressful nature of the task. Results validate the matching task as a laboratory stressor, with significant differences in HPA and ANS responsivity between conditions. The Stressor group exhibited a cortisol increase post-stressor, while the Control group was stable over time. Children in both conditions exhibited reduced parasympathetic activity to the first-half of the task, but in the second-half, only children in the Stressor condition, who were experiencing exaggerated signals of failure, exhibited further parasympathetic decline. The Stressor condition induced higher sympathetic activity (versus Control) throughout the task, with exaggerated second-half differences. Within the Stressor condition, responsivity was convergent across systems, with greater cortisol reactivity correlated with the magnitude of parasympathetic withdrawal and sympathetic engagement. Future research employing the matching task will facilitate understanding the role of HPA and ANS function in development. PMID:28024268

Patients with metabolic syndrome exhibit higher platelet activity than those with conventional risk factors for vascular disease.

PubMed

Serebruany, Victor L; Malinin, Alex; Ong, Stephen; Atar, Dan

2008-04-01

The metabolic syndrome is a matter of ongoing debate with regard to its existence, classification, clinical meaningfulness, and associated risks for vessel occlusion. Considering that persistent platelet activation is a cornerstone for the development of acute vascular events, and that patients with type 2 diabetes consistently exhibit high platelet activity, these characteristics may be critical for distinguishing and triageing specific features of metabolic syndrome among established risk factors for vascular disease. We assessed the platelet activity by conventional aggregation, expression of major surface receptors by flow cytometry, and quantitatively by rapid bedside analyzers in 20 aspirin-naïve patients with documented metabolic syndrome, and compared these with 20 untreated subjects with multiple cardiovascular risk factors. Closure time by the PFA-100 analyzer was significantly (P = 0.002) shorter in patients with metabolic syndrome indicating platelet inhibition under high shear conditions. Ultegra analyzer readings revealed increased fibrinogen binding (P = 0.0003) what in combination with the increased expression of PAC-1 (P = 0.32) strongly suggest activation of platelet glycoprotein IIb/IIIa receptor. Surface expression of CD107a (P = 0.014), and SPAN-12 (P = 0.003) were also higher in patients with metabolic syndrome. In contrast, platelet aggregation induced by collagen or ADP, CD31, CD41, CD42b, CD51/61, CD62p, CD63, CD154, CD165, so as formation of platelet-monocyte aggregates, PAR-1 thrombin receptor, and thrombospondin did not differ between groups. Patients with metabolic syndrome exhibited a higher degree of platelet activation than subjects with conventional risk factors for vascular disease. Conceptually, applying adequate antiplatelet strategies may reduce the risk of acute thrombotic events in these patients. Further prospective studies exploring this notion are encouraged.

Biochemical changes in mango after infection with Rhizoctonia bataticola.

PubMed

Vyas, H G; Chhatpar, H S

1980-04-15

Rhizoctonia bataticola is responsible for the spoilage of mango fruits (Mangifera india) during post-harvest preservation and storage. Culture of R. bataticola exhibited significant pectinase and cellulase activity. In Rhizoctonia-infected fruits an increase of protease and cellulase activity, and a decrease in certain enzymes of carbohydrate metabolism, were observed in comparison to healthy fruits.

Characterization of a mutated Geobacillus stearothermophilus L-arabinose isomerase that increases the production rate of D-tagatose.

PubMed

Kim, H-J; Kim, J-H; Oh, H-J; Oh, D-K

2006-07-01

Characterization of a mutated Geobacillus stearothermophilus L-arabinose isomerase used to increase the production rate of D-tagatose. A mutated gene was obtained by an error-prone polymerase chain reaction using L-arabinose isomerase gene from G. stearothermophilus as a template and the gene was expressed in Escherichia coli. The expressed mutated L-arabinose isomerase exhibited the change of three amino acids (Met322-->Val, Ser393-->Thr, and Val408-->Ala), compared with the wild-type enzyme and was then purified to homogeneity. The mutated enzyme had a maximum galactose isomerization activity at pH 8.0, 65 degrees C, and 1.0 mM Co2+, while the wild-type enzyme had a maximum activity at pH 8.0, 60 degrees C, and 1.0-mM Mn2+. The mutated L-arabinose isomerase exhibited increases in D-galactose isomerization activity, optimum temperature, catalytic efficiency (kcat/Km) for D-galactose, and the production rate of D-tagatose from D-galactose. The mutated L-arabinose isomerase from G. stearothermophilus is valuable for the commercial production of D-tagatose. This work contributes knowledge on the characterization of a mutated L-arabinose isomerase, and allows an increased production rate for D-tagatose from D-galactose using the mutated enzyme.

Moisture sorption isotherms and thermodynamic properties of bovine leather

NASA Astrophysics Data System (ADS)

Fakhfakh, Rihab; Mihoubi, Daoued; Kechaou, Nabil

2018-04-01

This study was aimed at the determination of bovine leather moisture sorption characteristics using a static gravimetric method at 30, 40, 50, 60 and 70 °C. The curves exhibit type II behaviour according to the BET classification. The sorption isotherms fitting by seven equations shows that GAB model is able to reproduce the equilibrium moisture content evolution with water activity for moisture range varying from 0.02 to 0.83 kg/kg d.b (0.9898 < R2 < 0.999). The sorption isotherms exhibit hysteresis effect. Additionally, sorption isotherms data were used to determine the thermodynamic properties such as isosteric heat of sorption, sorption entropy, spreading pressure, net integral enthalpy and entropy. Net isosteric heat of sorption and differential entropy were evaluated through direct use of moisture isotherms by applying the Clausius-Clapeyron equation and used to investigate the enthalpy-entropy compensation theory. Both sorption enthalpy and entropy for desorption increase to a maximum with increasing moisture content, and then decrease sharply with rising moisture content. Adsorption enthalpy decreases with increasing moisture content. Whereas, adsorption entropy increases smoothly with increasing moisture content to a maximum of 6.29 J/K.mol. Spreading pressure increases with rising water activity. The net integral enthalpy seemed to decrease and then increase to become asymptotic. The net integral entropy decreased with moisture content increase.

Reference memory, anxiety and estrous cyclicity in C57BL/6NIA mice are affected by age and sex.

PubMed

Frick, K M; Burlingame, L A; Arters, J A; Berger-Sweeney, J

2000-01-01

Age-related changes in learning and memory are common in rodents. However, direct comparisons of the effects of aging on learning and memory in both males and females are lacking. The present study examined whether memory deteriorates with increasing age in C57BL/6NIA mice, and whether age-related changes in learning and memory are similar in both sexes. Male and female mice (five, 17 and 25 months of age) were tested in a battery of behavioral tasks including the Morris water maze (spatial and non-spatial reference memory), simple odor discrimination (olfactory reference memory), plus maze (anxiety/exploration), locomotor activity, and basic reflexes. Five-month-old mice learned the water maze and odor discrimination tasks rapidly. Relative to five-month-old mice, 25-month-old mice exhibited impaired spatial and olfactory reference memory, but intact non-spatial reference memory. The spatial reference memory of 17-month-old mice was also impaired, but less so than 25-month mice. Seventeen-month-old mice exhibited intact non-spatial (visual and olfactory) reference memory. Five and 25-month-old mice had similar levels of plus maze exploration and locomotor activity, whereas 17-month-old mice were more active than both groups and were slightly less exploratory than five-month-old mice. Although sex differences were not observed in the five- and 25-month groups, 17-month-old females exhibited more impaired spatial reference memory and increased anxiety relative to 17-month-old males. Estrous cycling in females deteriorated significantly with increased age; all 25-month-old females had ceased cycling and 80% of 17-month-old females displayed either irregular or absent estrous cycling. This study is the first to directly compare age-related mnemonic decline in male and female mice. The results suggest that: (i) aged mice exhibit significant deficits in spatial and olfactory reference memory relative to young mice, whereas middle-aged mice exhibit only a moderate spatial memory deficit and; (ii) spatial reference memory decline begins at an earlier age in females than in males, a finding that may be related to the cessation of estrous cycling.

Properties of extracts from defatted rice bran by its subcritical water treatment.

PubMed

Wiboonsirikul, Jintana; Kimura, Yukitaka; Kadota, Megumi; Morita, Hisahiro; Tsuno, Takuo; Adachi, Shuji

2007-10-17

Defatted rice bran was extracted with water and subcritical water at 50-250 degrees C for 5 min. The highest extract yield was achieved at 200 degrees C, at which the maximum amounts of protein and carbohydrate were also obtained. The total phenolic and furfural contents, radical scavenging activity, and antioxidative activity for the autoxidation of linoleic acid increased with increasing treatment temperature. The bran extracts exhibited emulsifying activity except for the extract prepared at 250 degrees C, which was concomitant with the disappearance of its high-molecular-mass substances. The extract prepared at 200 degrees C also had the highest emulsion-stabilizing activity.

One exhibition, many goals. A case study on how to combine scientific questions with stakeholder views on effective communication of risks.

NASA Astrophysics Data System (ADS)

Charriere, M. K. M.; Junier, S.; Bogaard, T.; Mostert, E.; Malet, J. P.

2014-12-01

How effective is visual communication to increase awareness of natural hazards and risks? To answer this research question, we developed a research design that was at the same time an experimental setting and an actual communication effort. This contribution will address the scientists-stakeholders interaction that was involved, the resulting exhibition, the lessons learned and the value it had for the researchers and for the other stakeholders. Throughout the full length of the 2-years project held in the Ubaye valley (southeastern France) we collaborated with local and regional stakeholders (politicians and technicians). Informal meetings with local stakeholders were organized to determine what they perceived as the needs in term of risk communication and to investigate the potential to develop activities that would benefit both them and us. We were offered the opportunity to design an exhibition for the local public library. We proposed the content and this was adjusted in interaction with the stakeholders. Later local technicians and inhabitants contributed to the content of the exhibition and regional stakeholders helped with the funding of the exhibition. Finally, employees of the public library took the lead in advertising the activity, gathering participants and they helped designing the scientific survey. This survey was the key activity from a scientific point of view as it allowed us to measure the impact of this communication activity on risk awareness. Moreover, the principal scientist was present during all opening hours of the exhibition. This allowed direct and indirect contact with the visitors. The benefits of this exhibition for the community included triggering memories, encouraging exchanges, especially inter-generational, reinforcing stakeholders-to-stakeholders relationships and promote further communication on the topic. The scientific benefits are that we have an experiment that allows us to measure the impact of a communication effort, not in a laboratory situation but in real life.

Overexpression of Arabidopsis Molybdenum Cofactor Sulfurase Gene Confers Drought Tolerance in Maize (Zea mays L.)

PubMed Central

Zhang, Jiachang; Xiao, Yitao; Yue, Yuesen; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

2013-01-01

Abscisic acid (ABA) is a key component of the signaling system that integrates plant adaptive responses to abiotic stress. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene (LOS5) in maize markedly enhanced the expression of ZmAO and aldehyde oxidase (AO) activity, leading to ABA accumulation and increased drought tolerance. Transgenic maize (Zea mays L.) exhibited the expected reductions in stomatal aperture, which led to decreased water loss and maintenance of higher relative water content (RWC) and leaf water potential. Also, transgenic maize subjected to drought treatment exhibited lower leaf wilting, electrolyte leakage, malondialdehyde (MDA) and H2O2 content, and higher activities of antioxidative enzymes and proline content compared to wild-type (WT) maize. Moreover, overexpression of LOS5 enhanced the expression of stress-regulated genes such as Rad 17, NCED1, CAT1, and ZmP5CS1 under drought stress conditions, and increased root system development and biomass yield after re-watering. The increased drought tolerance in transgenic plants was associated with ABA accumulation via activated AO and expression of stress-related gene via ABA induction, which sequentially induced a set of favorable stress-related physiological and biochemical responses. PMID:23326325

Overexpression of Arabidopsis molybdenum cofactor sulfurase gene confers drought tolerance in maize (Zea mays L.).

PubMed

Lu, Yao; Li, Yajun; Zhang, Jiachang; Xiao, Yitao; Yue, Yuesen; Duan, Liusheng; Zhang, Mingcai; Li, Zhaohu

2013-01-01

Abscisic acid (ABA) is a key component of the signaling system that integrates plant adaptive responses to abiotic stress. Overexpression of Arabidopsis molybdenum cofactor sulfurase gene (LOS5) in maize markedly enhanced the expression of ZmAO and aldehyde oxidase (AO) activity, leading to ABA accumulation and increased drought tolerance. Transgenic maize (Zea mays L.) exhibited the expected reductions in stomatal aperture, which led to decreased water loss and maintenance of higher relative water content (RWC) and leaf water potential. Also, transgenic maize subjected to drought treatment exhibited lower leaf wilting, electrolyte leakage, malondialdehyde (MDA) and H(2)O(2) content, and higher activities of antioxidative enzymes and proline content compared to wild-type (WT) maize. Moreover, overexpression of LOS5 enhanced the expression of stress-regulated genes such as Rad 17, NCED1, CAT1, and ZmP5CS1 under drought stress conditions, and increased root system development and biomass yield after re-watering. The increased drought tolerance in transgenic plants was associated with ABA accumulation via activated AO and expression of stress-related gene via ABA induction, which sequentially induced a set of favorable stress-related physiological and biochemical responses.

ENERGY-NET (Energy, Environment and Society Learning Network): Best Practices to Enhance Informal Geoscience Learning

NASA Astrophysics Data System (ADS)

Rossi, R.; Elliott, E. M.; Bain, D.; Crowley, K. J.; Steiner, M. A.; Divers, M. T.; Hopkins, K. G.; Giarratani, L.; Gilmore, M. E.

2014-12-01

While energy links all living and non-living systems, the integration of energy, the environment, and society is often not clearly represented in 9 - 12 classrooms and informal learning venues. However, objective public learning that integrates these components is essential for improving public environmental literacy. ENERGY-NET (Energy, Environment and Society Learning Network) is a National Science Foundation funded initiative that uses an Earth Systems Science framework to guide experimental learning for high school students and to improve public learning opportunities regarding the energy-environment-society nexus in a Museum setting. One of the primary objectives of the ENERGY-NET project is to develop a rich set of experimental learning activities that are presented as exhibits at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania (USA). Here we detail the evolution of the ENERGY-NET exhibit building process and the subsequent evolution of exhibit content over the past three years. While preliminary plans included the development of five "exploration stations" (i.e., traveling activity carts) per calendar year, the opportunity arose to create a single, larger topical exhibit per semester, which was assumed to have a greater impact on museum visitors. Evaluative assessments conducted to date reveal important practices to be incorporated into ongoing exhibit development: 1) Undergraduate mentors and teen exhibit developers should receive additional content training to allow richer exhibit materials. 2) The development process should be distributed over as long a time period as possible and emphasize iteration. This project can serve as a model for other collaborations between geoscience departments and museums. In particular, these practices may streamline development of public presentations and increase the effectiveness of experimental learning activities.

A genetic dissection of the photophobic response of Paramecium tetraurelia.

PubMed

Hinrichsen, Robert; Peters, Christian

2013-05-01

Paramecium tetraurelia displayed two behavioral responses upon the initiation of a light stimulus at 7 x 10(4) lux. The cells exhibited a photophobic response in the form of behavioral avoiding reactions, followed by an increase in forward swimming velocity that was significantly higher than prior to the light stimulus activation. It was determined that an intensity of approximately 6.5 x 10(3) lux was required to initiate a moderate avoidance behavioral response. Following the avoiding response, a gradual increase in speed occurred as the intensity increased, indicating that increased swimming speeds are dependent on the light intensity. Two mutants, pawnA and Dancer, were utilized since they affect known Ca(2+)-currents of the cell. The use of pawnA cells, which lack voltage-dependent Ca(2+) channel activity, showed that the two responses to light could be genetically separated, in that the cells showed no avoiding reactions, but did increase their swimming speed. The Dancer cells, which display exaggerated Ca(2+) channel activity, exhibited similar initial avoiding responses as the wild type cells, however did not increase their swimming speed as the intensity of the light was increased. This phenotype as replicated in wildtype cells that had been placed in 25 μM 8-Br-cGMP. These data demonstrate that the photophobic light response of Paramecium tetraurelia can be genetically dissected as a means of elucidating the molecular mechanisms of the light response. Copyright © 2013 Elsevier GmbH. All rights reserved.

Translational Advancement of Somatostatin Gene Delivery for Disease Modification and Cognitive Sparing in Intractable Epilepsy

DTIC Science & Technology

2015-09-01

morphological analysis revealed significantly more activated (p < 0.001) and highly activated ( phagocytic ; p < 0.05) microglia in the dentate gyri of...process with small cell bodies (Figure 10A). Activated microglia exhibit less ramified processes and larger nuclei (Figure 10B) and phagocytic microglia...significantly increases in the dentate gyri of kindled rats along with the total number of highly activated or phagocytic microglia. We are currently

Monitoring very-long-period seismicity at Kilauea Volcano, Hawaii

USGS Publications Warehouse

Dawson, Phillip B.; Benítez, M. C.; Chouet, Bernard A.; Wilson, David; Okubo, Paul G.

2010-01-01

On 19 March, 2008 eruptive activity returned to the summit of Kilauea Volcano, Hawaii with the formation of a new vent within the Halemaumau pit crater. The new vent has been gradually increasing in size, and exhibiting sustained degassing and the episodic bursting of gas slugs at the surface of a lava pond ∼200 m below the floor of Halemaumau. The spectral characteristics, source location obtained by radial semblance, and Hidden Markov Model pattern recognition of the degassing burst signals are consistent with an increase in gas content in the magma transport system beginning in October, 2007. This increase plateaus between March – September 2008, and exhibits a fluctuating pattern until 31 January, 2010, suggesting that the release of gas is slowly diminishing over time.

Changes in activation energy and kinetics of heat-activated persulfate oxidation of phenol in response to changes in pH and temperature.

PubMed

Ma, Jie; Li, Haiyan; Chi, Liping; Chen, Hongkun; Chen, Changzhao

2017-12-01

Persulfate (peroxydisulfate, S 2 O 8 2- ) is the newest oxidant used for the in situ chemical oxidation (ISCO) remediation of soil and groundwater. The present study investigated impacts of solution pH, temperature, and persulfate concentration on the reaction rate constant (k 1 ), activation energy (E a ), and reaction order of the heat-activated persulfate process. Phenol was chosen as the model organic contaminant. As temperature increased from 30 °C to 70 °C, k 1 exhibited a significant increase from 0.003 h -1 ∼0.962 h -1 (pH 1.3-13.9) to 1.184 h -1 ∼9.91 h -1 (pH 1.3-13.9), which corroborated with the activation of persulfate using heat. As pH increased from 1.3 to 13.9, k 1 exhibited a 4.3-fold increase at 70 °C and a 320-fold increase at 30 °C, thereby suggesting that: 1) the phenol oxidation rate increased under alkaline conditions, and 2) the enhancement of reaction rate due to alkaline activation was more pronounced at a lower temperature. Increasing pH significantly reduced E a from 139.7 ± 1.3 kJ/mol at pH 1.3 to 52.0 ± 3.3 kJ/mol at pH 13.9. In contrast to changing pH, increasing persulfate concentration from 20 to 320 mM significantly increased k 1 but did not affect E a . Changes in E a suggest that persulfate oxidation of phenol experienced different reaction pathways or elementary reaction sequences as the pH changed from 1.3 to 13.9. In addition, the k 1 and E a data also suggest that a minimal pH threshold of ∼11 was required for the effective alkaline activation of persulfate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Working memory contributes to elevated motor activity in adults with ADHD: an examination of the role of central executive and storage/rehearsal processes.

PubMed

Hudec, Kristen L; Alderson, R Matt; Kasper, Lisa J; Patros, Connor H G

2014-05-01

The relationship between working memory (WM) and objectively measured motor activity was examined in adults with ADHD and healthy controls (HCs). Thirty-five adults (ADHD = 20, HC = 15) were grouped using self-report and collateral-report measures in addition to a semistructured clinical interview. All participants completed control conditions with minimal WM demands, and separate phonological (PH) and visuospatial (VS) WM tasks with recall demands ranging from four to seven stimuli. The ADHD group exhibited significantly more motor activity relative to the HC group, and both groups exhibited greater activity during PH and VS WM tasks, relative to control conditions. Finally, the central executive (CE) and PH storage/rehearsal subsystems were associated with large-magnitude between-group differences in activity. Findings suggest that increased demands on WM, particularly the CE and PH storage/rehearsal, contribute to ADHD-related hyperactivity, though a portion of excessive motor activity in adults with ADHD may occur independently of WM demands.

Coagulation Abnormalities of Sickle Cell Disease: Relationship with Clinical Outcomes and the Effect of Disease Modifying Therapies

PubMed Central

Noubouossie, Denis; Key, Nigel S.; Ataga, Kenneth I.

2015-01-01

Sickle cell disease (SCD) is a hypercoagulable state. Patients exhibit increased platelet activation, high plasma levels of markers of thrombin generation, depletion of natural anticoagulant proteins, abnormal activation of the fibrinolytic system, and increased tissue factor expression, even in the non-crisis “steady state.” Furthermore, SCD is characterized by an increased risk of thrombotic complications. The pathogenesis of coagulation activation in SCD appears to be multi-factorial, with contributions from ischemia-reperfusion injury and inflammation, hemolysis and nitric oxide deficiency, and increased sickle RBC phosphatidylserine expression. Recent studies in animal models suggest that activation of coagulation may contribute to the pathogenesis of SCD, but the data on the contribution of coagulation and platelet activation to SCD-related complications in humans are limited. Clinical trials of new generations of anticoagulants and antiplatelet agents, using a variety of clinical endpoints are warranted. PMID:26776344

Determinants of the Thrombogenic Potential of Multiwalled Carbon Nanotubes

PubMed Central

Burke, Andrew; Singh, Ravi; Carroll, David L.; Owen, John; Kock, Nancy D.; D’Agostino, Ralph; Torti, Frank M.; Torti, Suzy V.

2011-01-01

Multiwalled carbon nanotubes (MWCNTs) are cylindrical tubes of graphitic carbon with unique physical and electrical properties. MWCNTs are being explored for a variety of diagnostic and therapeutic applications. Successful biomedical application of MWCNTs will require compatibility with normal circulatory components, including constituents of the hemostatic cascades. In this manuscript, we compare the thrombotic activity of MWCNTs in vitro and in vivo. We also assess the influence of functionalization of MWCNTs on thrombotic activity. In vitro, MWCNT activate the intrinsic pathway of coagulation as measured by activated partial thromboplastin time (aPTT) assays. Functionalization by amidation or carboxylation enhances this procoagulant activity. Mechanistic studies demonstrate that MWCNTs enhance propagation of the intrinsic pathway via a non-classical mechanism strongly dependent on factor IX. MWCNTs preferentially associate with factor IXa and may provide a platform for its activation. In addition to their effects on the coagulation cascade, MWCNTs activate platelets in vitro, with amidated MWCNTs exhibiting greater platelet activation than carboxylated or pristine MWCNTs. However, contrasting trends are obtained in vivo, where functionalization tends to diminish rather than enhance pro-coagulant activity. Thus, following systemic injection of MWCNTs in mice, pristine MWCNTs decreased platelet counts, increased vWF, and increased D-dimers. In contrast, carboxylated MWCNTS exhibited little procoagulant tendency in vivo, eliciting only a mild and transient decrease in platelets. Amidated MWCNTs elicited no statistically significant change in platelet count. Further, neither carboxylated nor amidated MWCNTs increased vWF or D-dimers in mouse plasma. We conclude that the pro-coagulant tendencies of MWCNTs observed in vitro are not necessarily recapitulated in vivo. Further, functionalization can markedly attenuate the procoagulant activity of MWCNTs in vivo. This work will inform the rational development of biocompatible MWCNTs for systemic delivery. PMID:21663954

Cinnamomum cassia Essential Oil Inhibits α-MSH-Induced Melanin Production and Oxidative Stress in Murine B16 Melanoma Cells

PubMed Central

Chou, Su-Tze; Chang, Wen-Lun; Chang, Chen-Tien; Hsu, Shih-Lan; Lin, Yu-Che; Shih, Ying

2013-01-01

Essential oils extracted from aromatic plants exhibit important biological activities and have become increasingly important for the development of aromatherapy for complementary and alternative medicine. The essential oil extracted from Cinnamomum cassia Presl (CC-EO) has various functional properties; however, little information is available regarding its anti-tyrosinase and anti-melanogenic activities. In this study, 16 compounds in the CC-EO have been identified; the major components of this oil are cis-2-methoxycinnamic acid (43.06%) and cinnamaldehyde (42.37%). CC-EO and cinnamaldehyde exhibited anti-tyrosinase activities; however, cis-2-methoxycinnamic acid did not demonstrate tyrosinase inhibitory activity. In murine B16 melanoma cells stimulated with α-melanocyte-stimulating hormone (α-MSH), CC-EO and cinnamaldehyde not only reduced the melanin content and tyrosinase activity of the cells but also down-regulated tyrosinase expression without exhibiting cytotoxicity. Moreover, CC-EO and cinnamaldehyde decreased thiobarbituric acid-reactive substance (TBARS) levels and restored glutathione (GSH) and catalase activity in the α-MSH-stimulated B16 cells. These results demonstrate that CC-EO and its major component, cinnamaldehyde, possess potent anti-tyrosinase and anti-melanogenic activities that are coupled with antioxidant properties. Therefore, CC-EO may be a good source of skin-whitening agents and may have potential as an antioxidant in the future development of complementary and alternative medicine-based aromatherapy. PMID:24051402

Environmental enrichment for a mixed-species nocturnal mammal exhibit.

PubMed

Clark, Fay E; Melfi, Vicky A

2012-01-01

Environmental enrichment (EE) is an integral aspect of modern zoo animal management but, empirical evaluation of it is biased toward species housed in single-species groups. Nocturnal houses, where several nocturnal species are housed together, are particularly overlooked. This study investigated whether three species (nine-banded armadillos, Dasypus novemcinctus; Senegal bush babies, Galago senegalensis; two-toed sloths, Choloepus didactylus) in the nocturnal house at Paignton Zoo Environmental Park, UK could be enriched using food-based and sensory EE. Subjects were an adult male and female of each species. EE was deemed effective if it promoted target species-typical behaviors, behavioral diversity, and increased use of enriched exhibit zones. Results from generalized linear mixed models demonstrated that food-based EE elicited the most positive behavioral effects across species. One set of food-based EEs (Kong®, termite mound and hanging food) presented together was associated with a significant increase in species-typical behaviors, increased behavioral diversity, and increased use of enriched exhibit zones in armadillos and bush babies. Although one type of sensory EE (scented pine cones) increased overall exhibit use in all species, the other (rainforest sounds) was linked to a significant decrease in species-typical behavior in bush babies and sloths. There were no intra or interspecies conflicts over EE, and commensalism occurred between armadillos and bush babies. Our data demonstrate that simple food-based and sensory EE can promote positive behavioral changes in a mixed-species nocturnal mammal exhibit. We suggest that both food and sensory EE presented concurrently will maximize opportunities for naturalistic activity in all species. © 2011 Wiley Periodicals, Inc.

High-Dose Nicotinamide Suppresses ROS Generation and Augments Population Expansion during CD8(+) T Cell Activation.

PubMed

Choi, Ho Jin; Jang, So-Young; Hwang, Eun Seong

2015-10-01

During T cell activation, mitochondrial content increases to meet the high energy demand of rapid cell proliferation. With this increase, the level of reactive oxygen species (ROS) also increases and causes the rapid apoptotic death of activated cells, thereby facilitating T cell homeostasis. Nicotinamide (NAM) has previously been shown to enhance mitochondria quality and extend the replicative life span of human fibroblasts. In this study, we examined the effect of NAM on CD8(+) T cell activation. NAM treatment attenuated the increase of mitochondrial content and ROS in T cells activated by CD3/CD28 antibodies. This was accompanied by an accelerated and higher-level clonal expansion resulting from attenuated apoptotic death but not increased division of the activated cells. Attenuation of ROS-triggered pro-apoptotic events and upregulation of Bcl-2 expression appeared to be involved. Although cells activated in the presence of NAM exhibited compromised cytokine gene expression, our results suggest a means to augment the size of T cell expansion during activation without consuming their limited replicative potential.

Directed Evolution and Structural Analysis of Alkaline Pectate Lyase from the Alkaliphilic Bacterium Bacillus sp. Strain N16-5 To Improve Its Thermostability for Efficient Ramie Degumming.

PubMed

Zhou, Cheng; Ye, Jintong; Xue, Yanfen; Ma, Yanhe

2015-09-01

Thermostable alkaline pectate lyases have potential applications in the textile industry as an alternative to chemical-based ramie degumming processes. In particular, the alkaline pectate lyase from Bacillus sp. strain N16-5 (BspPelA) has potential for enzymatic ramie degumming because of its high specific activity under extremely alkaline conditions without the requirement for additional Ca(2+). However, BspPelA displays poor thermostability and is inactive after incubation at 50°C for only 30 min. Here, directed evolution was used to improve the thermostability of BspPelA for efficient and stable degumming. After two rounds of error-prone PCR and screening of >12,000 mutants, 10 mutants with improved thermostability were obtained. Sequence analysis and site-directed mutagenesis revealed that single E124I, T178A, and S271G substitutions were responsible for improving thermostability. Structural and molecular dynamic simulation analysis indicated that the formation of a hydrophobic cluster and new H-bond networks was the key factor contributing to the improvement in thermostability with these three substitutions. The most thermostable combined mutant, EAET, exhibited a 140-fold increase in the t50 (time at which the enzyme loses 50% of its initial activity) value at 50°C, accompanied by an 84.3% decrease in activity compared with that of wild-type BspPelA, while the most advantageous combined mutant, EA, exhibited a 24-fold increase in the t50 value at 50°C, with a 23.3% increase in activity. Ramie degumming with the EA mutant was more efficient than that with wild-type BspPelA. Collectively, our results suggest that the EA mutant, exhibiting remarkable improvements in thermostability and activity, has the potential for applications in ramie degumming in the textile industry. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Directed Evolution and Structural Analysis of Alkaline Pectate Lyase from the Alkaliphilic Bacterium Bacillus sp. Strain N16-5 To Improve Its Thermostability for Efficient Ramie Degumming

PubMed Central

Zhou, Cheng; Ye, Jintong; Xue, Yanfen

2015-01-01

Thermostable alkaline pectate lyases have potential applications in the textile industry as an alternative to chemical-based ramie degumming processes. In particular, the alkaline pectate lyase from Bacillus sp. strain N16-5 (BspPelA) has potential for enzymatic ramie degumming because of its high specific activity under extremely alkaline conditions without the requirement for additional Ca2+. However, BspPelA displays poor thermostability and is inactive after incubation at 50°C for only 30 min. Here, directed evolution was used to improve the thermostability of BspPelA for efficient and stable degumming. After two rounds of error-prone PCR and screening of >12,000 mutants, 10 mutants with improved thermostability were obtained. Sequence analysis and site-directed mutagenesis revealed that single E124I, T178A, and S271G substitutions were responsible for improving thermostability. Structural and molecular dynamic simulation analysis indicated that the formation of a hydrophobic cluster and new H-bond networks was the key factor contributing to the improvement in thermostability with these three substitutions. The most thermostable combined mutant, EAET, exhibited a 140-fold increase in the t50 (time at which the enzyme loses 50% of its initial activity) value at 50°C, accompanied by an 84.3% decrease in activity compared with that of wild-type BspPelA, while the most advantageous combined mutant, EA, exhibited a 24-fold increase in the t50 value at 50°C, with a 23.3% increase in activity. Ramie degumming with the EA mutant was more efficient than that with wild-type BspPelA. Collectively, our results suggest that the EA mutant, exhibiting remarkable improvements in thermostability and activity, has the potential for applications in ramie degumming in the textile industry. PMID:26070675

Individual effects of seasonal changes, visitor density, and concurrent bear behavior on stereotypical behaviors in captive polar bears (Ursus maritimus).

PubMed

Kelly, Krista R; Harrison, Michelle L; Size, Daniele D; MacDonald, Suzanne E

2015-01-01

Stereotypical behaviors in captive polar bears (Ursus maritimus) can be detrimental to their welfare. These behaviors can be reduced through enrichment programs but are often not completely eliminated, so identifying potential triggers is important. The present study investigated the influences of seasonal changes, visitor density, and concurrent bear activity on stereotypical behaviors exhibited by 3 captive polar bears at the Toronto Zoo. All bears exhibited these behaviors; however, individual differences were found in duration and form. The male exhibited less stereotypical behavior during spring, and the females exhibited less stereotypical behavior during winter. An increase in visitor density was associated with more stereotypical behavior in 1 female but less stereotypical behavior in the other 2 bears. All bears engaged in more stereotypical behaviors when the other bears were inactive, and 1 female engaged in more stereotypical behaviors when the other bears were out of sight. Further, when conspecifics were active, all bears engaged in less stereotypical behaviors. Given the variability among individual bears, future enrichment programs must be tailored to the needs of individuals to maximize efficacy.

Experimental measurements of U60 nanocluster stability in aqueous solution

NASA Astrophysics Data System (ADS)

Flynn, Shannon L.; Szymanowski, Jennifer E. S.; Gao, Yunyi; Liu, Tianbo; Burns, Peter C.; Fein, Jeremy B.

2015-05-01

In this study, the aqueous behavior of isolated U60 nanoclusters (K16Li25[UO2(O2)OH]60)-19 was studied under several pH conditions and nanocluster concentrations to determine if the nanoclusters exhibit solid phase buffering behavior or if they exhibit behavior more like aqueous complexes. U60 is a cage cluster consisting of 60 (UO2)(O2)2(OH)2 uranyl polyhedral which share OH and O2 groups with their neighboring uranyl polyhedral, resulting in negatively charged cage clusters whose charge is at least partially offset by K+ and Li+ in the aqueous phase. Batch experiments to monitor nanocluster stability were conducted for 16 days at pH 7.5, 8.0 and 8.5 at nanocluster suspension concentrations of 1.4, 2.8 and 6.0 g/L. The aqueous concentrations of U, Li, and K, determined after 10 kDa molecular weight filtration, achieved steady-state with the nanoclusters within 24 h. The steady-state aqueous U, Li, and K concentrations were independent of solution pH, however they increased with increasing nanocluster concentration, indicating that the nanoclusters do not buffer the aqueous activities as a bulk solid phase would, but exhibit behavior that is more characteristic of dissolved aqueous complexes. The ion activity product (I.A.P.) value was calculated using two approaches: (1) treating the nanoclusters as a solid phase with an activity of one, and (2) treating the nanoclusters as aqueous complexes with a non-unit activity equal to their concentration in solution. The I.A.P. values that were calculated with non-unit activity for the nanoclusters exhibited significantly less variation as a function of nanocluster concentration compared to the I.A.P. values calculated with a nanocluster activity of one. The results yield a calculated log dissociation constant for the U60 nanoclusters of 9.2 + 0.2/-0.3 (1σ). Our findings provide a better understanding of the thermodynamic stability and behavior of U60 nanoclusters in aqueous systems, and can be used to estimate the dissociation behavior of nanoclusters under a range of aqueous conditions.

Gender differences in methionine accumulation and metabolism in freshly isolated mouse hepatocytes: Potential roles in toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dever, Joseph T.; Elfarra, Adnan A.

L-Methionine (Met) is hepatotoxic at high concentrations. Because Met toxicity in freshly isolated mouse hepatocytes is gender-dependent, the goal of this study was to assess the roles of Met accumulation and metabolism in the increased sensitivity of male hepatocytes to Met toxicity compared with female hepatocytes. Male hepatocytes incubated with Met (30 mM) at 37 {sup o}C exhibited higher levels of intracellular Met at 0.5, 1.0, and 1.5 h, respectively, compared to female hepatocytes. Conversely, female hepatocytes had higher levels of S-adenosyl-L-methionine compared to male hepatocytes. Female hepatocytes also exhibited higher L-methionine-L-sulfoxide levels relative to control hepatocytes, whereas the increasesmore » in L-methionine-D-sulfoxide (Met-D-O) levels were similar in hepatocytes of both genders. Addition of aminooxyacetic acid (AOAA), an inhibitor of Met transamination, significantly increased Met levels at 1.5 h and increased Met-D-O levels at 1.0 and 1.5 h only in Met-exposed male hepatocytes. No gender differences in cytosolic Met transamination activity by glutamine transaminase K were detected. However, female mouse liver cytosol exhibited higher methionine-DL-sulfoxide (MetO) reductase activity than male mouse liver cytosol at low (0.25 and 0.5 mM) MetO concentrations. Collectively, these results suggest that increased cellular Met accumulation, decreased Met transmethylation, and increased Met and MetO transamination in male mouse hepatocytes may be contributing to the higher sensitivity of the male mouse hepatocytes to Met toxicity in comparison with female mouse hepatocytes.« less

Production of polygalacturonase from Coriolus versicolor grown on tomato pomace and its chromatographic behaviour on immobilized metal chelates.

PubMed

do Rosário Freixo, Maria; Karmali, Amin; Arteiro, José Maria

2008-06-01

Tomato pomace and pectin were used as the sole carbon sources for the production of polygalacturonase from a strain of Coriolus versicolor in submerged culture. The culture of C. versicolor grown on tomato pomace exhibited a peak of polygalacturonase activity (1,427 U/l) on the third day of culture with a specific activity of 14.5 U/mg protein. The production of polygalacturonase by C. versicolor grown on pectin as a sole carbon source increased with the time of cultivation, reaching a maximum activity of 3,207 U/l of fermentation broth with a specific activity of 248 U/mg protein. The levels of different isoenzymes of polygalacturonase produced during the culture growth were analysed by native PAGE. Differential chromatographic behaviour of lignocellulosic enzymes produced by C. versicolor (i.e. polygalacturonase, xylanase and laccase) was studied on immobilized metal chelates. The effect of ligand concentration, pH, the length of spacer arm and the nature of metal ion were studied for enzyme adsorption on immobilized metal affinity chromatography (IMAC). The adsorption of these lignocellulosic enzymes onto immobilized metal chelates was pH-dependent since an increase in protein adsorption was observed as the pH was increased from 6.0 to 8.0. The adsorption of polygalacturonase as well as other enzymes to immobilized metal chelates was due to coordination of histidine residues which are available at the protein surface since the presence of imidazole in the equilibration buffer abolished the adsorption of the enzyme to immobilized metal chelates. A one-step purification of polygalacturonase from C. versicolor was devised by using a column of Sepharose 6B-EPI 30-IDA-Cu(II) and purified enzyme exhibited a specific activity of about 150 U/mg protein, final recovery of enzyme activity of 100% and a purification factor of about 10. The use of short spacer arm and the presence of imidazole in equilibration buffer exhibited a higher selectivity for purification of polygalacturonase on this column with a high purification factor. The purified enzyme preparation was analysed by SDS-PAGE as well as by "in situ" detection of enzyme activity.

Neural correlates of cognitive and affective processing in maltreated youth with posttraumatic stress symptoms: Does gender matter?

PubMed Central

Crozier, Joseph C.; Wang, Lihong; Huettel, Scott A.; De Bellis, Michael D.

2014-01-01

We investigated the relationship of gender to cognitive and affective processing in maltreated youth with posttraumatic stress disorder (PTSD) symptoms using functional magnetic resonance imaging. Maltreated (N=29; n=13 females, n=16 males) and non-maltreated participants (N=45; n=26 females, n=19 males) performed an emotional oddball task that involved detection of targets with fear or scrambled face distractors. Results were moderated by gender. During the executive component of this task, left precuneus/posterior middle cingulate hypoactivation to fear versus calm or scrambled face targets were seen in maltreated versus control males and may represent dysfunction and less resilience in attentional networks. Maltreated males also showed decreased activation in the inferior frontal gyrus compared to control males. No differences were found in females. Posterior cingulate activations positively correlated with PTSD symptoms. While viewing fear faces, maltreated females exhibited decreased activity in dorsomedial prefrontal cortex and cerebellum I–VI; whereas maltreated males exhibited increased activity in left hippocampus, fusiform cortex, right cerebellar crus I, and visual cortex compared to their same gender controls. Gender by maltreatment effects were not attributable to demographic, clinical, or maltreatment parameters. Maltreated girls and boys exhibited distinct patterns of neural activations during executive and affective processing, a new finding in the maltreatment literature. PMID:24621958

Neural correlates of cognitive and affective processing in maltreated youth with posttraumatic stress symptoms: does gender matter?

PubMed

Crozier, Joseph C; Wang, Lihong; Huettel, Scott A; De Bellis, Michael D

2014-05-01

We investigated the relationship of gender to cognitive and affective processing in maltreated youth with posttraumatic stress disorder symptoms using functional magnetic resonance imaging. Maltreated (N = 29, 13 females, 16 males) and nonmaltreated participants (N = 45, 26 females, 19 males) performed an emotional oddball task that involved detection of targets with fear or scrambled face distractors. Results were moderated by gender. During the executive component of this task, left precuneus/posterior middle cingulate hypoactivation to fear versus calm or scrambled face targets were seen in maltreated versus control males and may represent dysfunction and less resilience in attentional networks. Maltreated males also showed decreased activation in the inferior frontal gyrus compared to control males. No differences were found in females. Posterior cingulate activations positively correlated with posttraumatic stress disorder symptoms. While viewing fear faces, maltreated females exhibited decreased activity in the dorsomedial prefrontal cortex and cerebellum I-VI, whereas maltreated males exhibited increased activity in the left hippocampus, fusiform cortex, right cerebellar crus I, and visual cortex compared to their same-gender controls. Gender by maltreatment effects were not attributable to demographic, clinical, or maltreatment parameters. Maltreated girls and boys exhibited distinct patterns of neural activations during executive and affective processing, a new finding in the maltreatment literature.

The effects of DAT1 genotype on fMRI activation in an emotional go/no-go task.

PubMed

Brown, Brenna K; Murrell, Jill; Karne, Harish; Anand, Amit

2017-02-01

Dopaminergic brain circuits participate in emotional processing and impulsivity. The dopamine transporter (DAT) modulates dopamine reuptake. A variable number tandem repeat (VNTR) in the dopamine transporter gene (DAT1) affects DAT expression. The influence of DAT1 genotype on neural activation during emotional processing and impulse inhibition has not been examined. Forty-two healthy subjects were classified as 9DAT (n = 17) or 10DAT (n = 25) based on DAT1 genotype (9DAT = 9R/9R and 9R/10R; 10DAT = 10R/10R). Subjects underwent fMRI during non-emotional and emotional go/no-go tasks. Subjects were instructed to inhibit responses to letters, happy faces, or sad faces in separate blocks. Accuracy and reaction time did not differ between groups. Within group results showed activation in regions previously implicated in emotional processing and response inhibition. Between groups results showed increased activation in 9DAT individuals during inhibition. During letter inhibition, 9DAT individuals exhibited greater activation in right inferior parietal regions. During sad inhibition, 9DAT Individuals exhibited greater activation in frontal, posterior cingulate, precuneus, right cerebellar, left paracentral, and right occipital brain regions. The interaction between DAT genotype and response type in sad versus letter stimuli showed increased activation in 9DAT individuals during sad no-go responses in the anterior cingulate cortex, extending into frontal-orbital regions. 9DAT individuals have greater activation than 10DAT individuals during neutral and sad inhibition, showing that genotypic variation influencing basal dopamine levels can alter the neural basis of emotional processing and response inhibition. This may indicate that 9R carriers exert more effort to overcome increased basal dopamine activation when inhibiting responses in emotional contexts.

Choline kinase β mutant mice exhibit reduced phosphocholine, elevated osteoclast activity, and low bone mass.

PubMed

Kular, Jasreen; Tickner, Jennifer C; Pavlos, Nathan J; Viola, Helena M; Abel, Tamara; Lim, Bay Sie; Yang, Xiaohong; Chen, Honghui; Cook, Robert; Hool, Livia C; Zheng, Ming Hao; Xu, Jiake

2015-01-16

The maintenance of bone homeostasis requires tight coupling between bone-forming osteoblasts and bone-resorbing osteoclasts. However, the precise molecular mechanism(s) underlying the differentiation and activities of these specialized cells are still largely unknown. Here, we identify choline kinase β (CHKB), a kinase involved in the biosynthesis of phosphatidylcholine, as a novel regulator of bone homeostasis. Choline kinase β mutant mice (flp/flp) exhibit a systemic low bone mass phenotype. Consistently, osteoclast numbers and activity are elevated in flp/flp mice. Interestingly, osteoclasts derived from flp/flp mice exhibit reduced sensitivity to excessive levels of extracellular calcium, which could account for the increased bone resorption. Conversely, supplementation of cytidine 5'-diphosphocholine in vivo and in vitro, a regimen that bypasses CHKB deficiency, restores osteoclast numbers to physiological levels. Finally, we demonstrate that, in addition to modulating osteoclast formation and function, loss of CHKB corresponds with a reduction in bone formation by osteoblasts. Taken together, these data posit CHKB as a new modulator of bone homeostasis. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

A supermolecular curcumin for enhanced antiproliferative and proapoptotic activities: molecular characteristics, computer modeling and in vivo pharmacokinetics

NASA Astrophysics Data System (ADS)

Tan, Qunyou; Wu, Jianyong; Li, Yi; Mei, Hu; Zhao, Chunjing; Zhang, Jingqing

2013-01-01

The supermolecular curcumin (SMCCM) exhibiting remarkably improved solubility and release characteristics was fabricated to increase the oral bioavailability in rat as well as the antiproliferative and proapoptotic activities of curcumin (CCM) against human lung adenocarcinoma cell A549. SMCCM was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, morphology and structure, aqueous solubility, and release behavior in vitro. Computer modeling of the supermolecular structure was performed. The pharmacokinetics, antiproliferative and proapoptotic activities of SMCCM were evaluated. The mechanisms by which SMCCM inhibited proliferation and induced apoptosis were identified. The formation of SMCCM was testified and the supermolecular structure was studied by a computer modeling technique. Compared to free CCM, SMCCM with much higher aqueous solubility exhibited obviously enhanced release and more favorable pharmacokinetic profiles, and, furthermore, SMCCM showed higher anticancer efficacy, enhanced induction of G2/M-phase arrest and apoptosis in A549 cells, which might be involved with the increases in reactive oxygen species production and intracellular Ca2+ accumulation, and a decrease in mitochondrial membrane potential. SMCCM remarkably enhanced not only the oral bioavailability but also the antiproliferative and proapoptotic activities of CCM along with improved solubility and release characteristics of CCM.

New synthesis and antiparasitic activity of model 5-aryl-1-methyl-4-nitroimidazoles.

PubMed

Saadeh, Haythem A; Mosleh, Ibrahim M; El-Abadelah, Mustafa M

2009-07-27

A number of 5-aryl-1-methyl-4-nitroimidazoles 5a-f have been synthesized in good yields by the Suzuki coupling reaction between 5-chloro-1-methyl-4-nitroimidazole (3) and arylboronic acids 4a-f, aided by dichlorobis-(triphenylphosphine)palladium(II), K(2)CO(3, )and tetrabutylammonium bromide in water at 70-80 degrees C. Compounds 5a-f were characterized by elemental analysis, NMR and MS spectral data. On the basis of in vitro screening data, 5-(3-chlorophenyl)-1-methyl-4-nitro-1H-imidazole (5f) exhibited potent lethal activity against Entamoeba histolytica and Giardia intestinalis with IC(50) = 1.47 microM/mL, a value lower by a factor of two than that of the standard drug, metronidazole. The boosted activity of 5f was not accompanied by any increased cytotoxicity.The rest of the series also exhibited potent antiparasitic activity with IC(50 ) values in the 1.72-4.43 microM/mL range. The cytotoxicity of the derivatives 5c and 5e was increased compared to the precursor compound, metronidazole, although they remain non-cytotoxic at concentrations much higher than the antiparasitic concentration of the two derivatives.

A supermolecular curcumin for enhanced antiproliferative and proapoptotic activities: molecular characteristics, computer modeling and in vivo pharmacokinetics.

PubMed

Tan, Qunyou; Wu, Jianyong; Li, Yi; Mei, Hu; Zhao, Chunjing; Zhang, Jingqing

2013-01-25

The supermolecular curcumin (SMCCM) exhibiting remarkably improved solubility and release characteristics was fabricated to increase the oral bioavailability in rat as well as the antiproliferative and proapoptotic activities of curcumin (CCM) against human lung adenocarcinoma cell A549. SMCCM was characterized by differential scanning calorimetry, Fourier transform infrared spectroscopy, morphology and structure, aqueous solubility, and release behavior in vitro. Computer modeling of the supermolecular structure was performed. The pharmacokinetics, antiproliferative and proapoptotic activities of SMCCM were evaluated. The mechanisms by which SMCCM inhibited proliferation and induced apoptosis were identified. The formation of SMCCM was testified and the supermolecular structure was studied by a computer modeling technique. Compared to free CCM, SMCCM with much higher aqueous solubility exhibited obviously enhanced release and more favorable pharmacokinetic profiles, and, furthermore, SMCCM showed higher anticancer efficacy, enhanced induction of G2/M-phase arrest and apoptosis in A549 cells, which might be involved with the increases in reactive oxygen species production and intracellular Ca(2+) accumulation, and a decrease in mitochondrial membrane potential. SMCCM remarkably enhanced not only the oral bioavailability but also the antiproliferative and proapoptotic activities of CCM along with improved solubility and release characteristics of CCM.

Highly-efficient photocatalytic degradation of methylene blue by PoPD-modified TiO 2 nanocomposites due to photosensitization-synergetic effect of TiO2 with PoPD.

PubMed

Yang, Chuanxi; Dong, Wenping; Cui, Guanwei; Zhao, Yingqiang; Shi, Xifeng; Xia, Xinyuan; Tang, Bo; Wang, Weiliang

2017-06-21

Poly-o-phenylenediamine modified TiO 2 nanocomposites were successfully synthesized via an 'in situ' oxidative polymerization method. The modified nanocomposites were characterized by BET, XRD, TEM, FT-IR, TGA, XPS, EA and UV-Vis DRS. The photocatalytic degradation of methylene blue was chosen as a model reaction to evaluate the photocatalytic activities of TiO 2 and PoPD/TiO 2 . The results indicated that PoPD/TiO 2 nanocomposites exhibited good photocatalytic activity and stability. The photocatalytic activity of PoPD/TiO 2 increased as the initial pH increased because of electrostatic adsorption between the photocatalyst and MB as well as the generation of ·OH, whereas it exhibited an earlier increasing and later decreasing trend as the concentration of the photocatalyst increased owing to the absorption of visible light. The photocatalytic stability of the PoPD/TiO 2 nanocomposite was dependent on the stability of its structure. Based on radical trapping experiments and ESR measurements, the origin of oxidizing ability of PoPD/TiO 2 nanocomposites on photocatalytic degradation of MB was proposed, which taking into account of ·OH and ·O 2 - were the first and second important ROS, respectively. The possible photocatalytic mechanism and photocatalytic activity enhanced mechanism has been proposed, taking into account the photosensitization effect and synergetic effect of TiO 2 with PoPD.

Tacrolimus Increases the Effectiveness of Itraconazole and Fluconazole against Sporothrix spp.

PubMed Central

Borba-Santos, Luana P.; Reis de Sá, Leandro F.; Ramos, Juliene A.; Rodrigues, Anderson M.; de Camargo, Zoilo P.; Rozental, Sonia; Ferreira-Pereira, Antonio

2017-01-01

Calcineurin inhibitors – such as the clinically used drug tacrolimus – are active against important fungal pathogens, particularly when combined with azoles. However, tacrolimus has not been tested against sporotrichosis, an endemic subcutaneous mycosis with worldwide distribution. Here, we evaluated the activity of tacrolimus and cyclosporine A in vitro – as monotherapy and in combination with itraconazole or fluconazole – against yeasts of Sporothrix brasiliensis and S. schenckii, the main sporotrichosis agents in Brazil. We also analyzed the effect of tacrolimus treatment on intracellular neutral lipid levels, which typically increase after azole treatment. Tacrolimus inhibited the growth of yeasts from S. brasiliensis and S. schenckii reference isolates, with minimum inhibitory concentration (MIC) values (required for ≥50% growth inhibition) of 1 and 2 mg/L, respectively. Importantly, the combination of tacrolimus and azoles exhibited high synergy toward reference Sporothrix isolates. Tacrolimus combined with itraconazole significantly increased neutral lipid accumulation in S. brasiliensis, but not in S. schenckii. Clinical isolates of S. brasiliensis and S. schenckii were more sensitive to tacrolimus as monotherapy than feline-borne isolates, however, synergy between tacrolimus and azoles was only observed for feline-borne isolates. Cyclosporine A was effective against S. brasiliensis and S. schenckii as monotherapy (MIC = 1 mg/L), but exhibited no synergy with itraconazole and fluconazole. We conclude that tacrolimus has promising antifungal activity against sporotrichosis agents, and also increases the activity of the current anti-sporotrichosis therapy (itraconazole and fluconazole) in combination assays against S. brasiliensis feline-borne isolates. PMID:28966608

Tacrolimus Increases the Effectiveness of Itraconazole and Fluconazole against Sporothrix spp.

PubMed

Borba-Santos, Luana P; Reis de Sá, Leandro F; Ramos, Juliene A; Rodrigues, Anderson M; de Camargo, Zoilo P; Rozental, Sonia; Ferreira-Pereira, Antonio

2017-01-01

Calcineurin inhibitors - such as the clinically used drug tacrolimus - are active against important fungal pathogens, particularly when combined with azoles. However, tacrolimus has not been tested against sporotrichosis, an endemic subcutaneous mycosis with worldwide distribution. Here, we evaluated the activity of tacrolimus and cyclosporine A in vitro - as monotherapy and in combination with itraconazole or fluconazole - against yeasts of Sporothrix brasiliensis and S. schenckii , the main sporotrichosis agents in Brazil. We also analyzed the effect of tacrolimus treatment on intracellular neutral lipid levels, which typically increase after azole treatment. Tacrolimus inhibited the growth of yeasts from S. brasiliensis and S. schenckii reference isolates, with minimum inhibitory concentration (MIC) values (required for ≥50% growth inhibition) of 1 and 2 mg/L, respectively. Importantly, the combination of tacrolimus and azoles exhibited high synergy toward reference Sporothrix isolates. Tacrolimus combined with itraconazole significantly increased neutral lipid accumulation in S. brasiliensis , but not in S. schenckii . Clinical isolates of S. brasiliensis and S. schenckii were more sensitive to tacrolimus as monotherapy than feline-borne isolates, however, synergy between tacrolimus and azoles was only observed for feline-borne isolates. Cyclosporine A was effective against S. brasiliensis and S. schenckii as monotherapy (MIC = 1 mg/L), but exhibited no synergy with itraconazole and fluconazole. We conclude that tacrolimus has promising antifungal activity against sporotrichosis agents, and also increases the activity of the current anti-sporotrichosis therapy (itraconazole and fluconazole) in combination assays against S. brasiliensis feline-borne isolates.

Role of Fyn-mediated NMDA receptor function in prediabetic neuropathy in mice

PubMed Central

Suo, Meng; Wang, Ping

2016-01-01

Diabetic neuropathy is a common complication of diabetes. This study evaluated the role of Fyn kinase and N-methyl-d-aspartate receptors (NMDARs) in the spinal cord in diabetic neuropathy using an animal model of high-fat diet-induced prediabetes. We found that prediabetic wild-type mice exhibited tactile allodynia and thermal hypoalgesia after a 16-wk high-fat diet, relative to normal diet-fed wild-type mice. Furthermore, prediabetic wild-type mice exhibited increased tactile allodynia and thermal hypoalgesia at 24 wk relative to 16 wk. Such phenomena were correlated with increased expression and activation of NR2B subunit of NMDARs, as well as Fyn-NR2B interaction in the spinal cord. Fyn−/− mice developed prediabetes after 16-wk high-fat diet treatment and exhibited thermal hypoalgesia, without showing tactile allodynia or altered expression and activation of NR2B subunit, relative to normal diet-fed Fyn−/− mice. Finally, intrathecal administrations of Ro 25-6981 (selective NR2B subunit-containing NMDAR antagonist) dose-dependently alleviated tactile allodynia, but not thermal hypoalgesia, at 16 and 24 wk in prediabetic wild-type mice. Our results suggested that Fyn-mediated NR2B signaling plays a critical role in regulation of prediabetic neuropathy and that the increased expression/function of NR2B subunit-containing NMDARs may contribute to the progression of neuropathy in type 2 diabetes. PMID:27146985

MgO-templated carbon as a negative electrode material for Na-ion capacitors

NASA Astrophysics Data System (ADS)

Kado, Yuya; Soneda, Yasushi

2016-12-01

In this study, MgO-templated carbon with different pore structures was investigated as a negative electrode material for Na-ion capacitors. With increasing the Brunauer-Emmett-Teller surface area, the irreversible capacity increased, and the coulombic efficiency of the 1st cycle decreased because of the formation of solid electrolyte interface layers. MgO-templated carbon annealed at 1000 °C exhibited the highest capacity and best rate performance, suggesting that an appropriate balance between surface area and crystallinity is imperative for fast Na-ion storage, attributed to the storage mechanism: combination of non-faradaic electric double-layer capacitance and faradaic Na intercalation in the carbon layers. Finally, a Na-ion capacitor cell using MgO-templated carbon and activated carbon as the negative and positive electrodes, respectively, exhibited an energy density at high power density significantly greater than that exhibited by the cell using a commercial hard carbon negative electrode.

Enhanced Locomotor Activity Is Required to Exert Dietary Restriction-Dependent Increase of Stress Resistance in Drosophila.

PubMed

Ghimire, Saurav; Kim, Man Su

2015-01-01

Dietary restriction (DR) is known to be one of the most effective interventions to increase stress resistance, yet the mechanisms remain elusive. One of the most obvious DR-induced changes in phenotype is an increase in locomotor activity. Although it is conceptually perceivable that nutritional scarcity should prompt enhanced foraging behavior to garner additional dietary resources, the significance of enhanced movement activity has not been associated with the DR-dependent increase of stress resistance. In this study, we confirmed that flies raised on DR exhibited enhanced locomotive activity and increased stress resistance. Excision of fly wings minimized the DR-induced increase in locomotive activity, which resulted in attenuation of the DR-dependent increase of stress resistance. The possibility that wing clipping counteracts the DR by coercing flies to have more intake was ruled out since it did not induce any weight gain. Rather it was found that elimination of reactive oxygen species (ROS) that is enhanced by DR-induced upregulation of expression of antioxidant genes was significantly reduced by wing clipping. Collectively, our data suggests that DR increased stress resistance by increasing the locomotor activity, which upregulated expression of protective genes including, but not limited to, ROS scavenger system.

Spermidine/spermine N1-acetyltransferase (SSAT) activity in human small-cell lung carcinoma cells following transfection with a genomic SSAT construct.

PubMed

Murray-Stewart, Tracy; Applegren, Nancy B; Devereux, Wendy; Hacker, Amy; Smith, Renee; Wang, Yanlin; Casero, Robert A

2003-07-15

Spermidine/spermine N (1)-acetyltransferase (SSAT) activity is typically highly inducible in non-small-cell lung carcinomas in response to treatment with anti-tumour polyamine analogues, and this induction is associated with subsequent cell death. In contrast, cells of the small-cell lung carcinoma (SCLC) phenotype generally do not respond to these compounds with an increase in SSAT activity, and usually are only moderately affected with respect to growth. The goal of the present study was to produce an SSAT-overexpressing SCLC cell line to further investigate the role of SSAT in response to these anti-tumour analogues. To accomplish this, NCI-H82 SCLC cells were stably transfected with plasmids containing either the SSAT genomic sequence or the corresponding cDNA sequence. Individual clones were selected based on their ability to show induced SSAT activity in response to exposure to a polyamine analogue, and an increase in the steady-state SSAT mRNA level. Cells transfected with the genomic sequence exhibited a significant increase in basal SSAT mRNA expression, as well as enhanced SSAT activity, intracellular polyamine pool depletion and growth inhibition following treatment with the analogue N (1), N (11)-bis(ethyl)norspermine. Cells containing the transfected cDNA also exhibited an increase in the basal SSAT mRNA level, but remained phenotypically similar to vector control cells with respect to their response to analogue exposure. These studies indicate that both the genomic SSAT sequence and polyamine analogue exposure play a role in the transcriptional and post-transcriptional regulation and subsequent induction of SSAT activity in these cells. Furthermore, this is the first production of a cell line capable of SSAT protein induction from a generally unresponsive parent line.

Discovery of novel antimicrobial peptides: A transcriptomic study of the sea anemone Cnidopus japonicus.

PubMed

Grafskaia, Ekaterina N; Polina, Nadezhda F; Babenko, Vladislav V; Kharlampieva, Daria D; Bobrovsky, Pavel A; Manuvera, Valentin A; Farafonova, Tatyana E; Anikanov, Nikolay A; Lazarev, Vassili N

2018-04-01

As essential conservative component of the innate immune systems of living organisms, antimicrobial peptides (AMPs) could complement pharmaceuticals that increasingly fail to combat various pathogens exhibiting increased resistance to microbial antibiotics. Among the properties of AMPs that suggest their potential as therapeutic agents, diverse peptides in the venoms of various predators demonstrate antimicrobial activity and kill a wide range of microorganisms. To identify potent AMPs, the study reported here involved a transcriptomic profiling of the tentacle secretion of the sea anemone Cnidopus japonicus. An in silico search algorithm designed to discover toxin-like proteins containing AMPs was developed based on the evaluation of the properties and structural peculiarities of amino acid sequences. The algorithm revealed new proteins of the anemone containing antimicrobial candidate sequences, and 10 AMPs verified using high-throughput proteomics were synthesized. The antimicrobial activity of the candidate molecules was experimentally estimated against Gram-positive and -negative bacteria. Ultimately, three peptides exhibited antimicrobial activity against bacterial strains, which suggests that the method can be applied to reveal new AMPs in the venoms of other predators as well.

Secreted Frizzled-related protein 2 as a target in antifibrotic therapeutic intervention.

PubMed

Mastri, Michalis; Shah, Zaeem; Hsieh, Karin; Wang, Xiaowen; Wooldridge, Bailey; Martin, Sean; Suzuki, Gen; Lee, Techung

2014-03-15

Progressive fibrosis is a pathological hallmark of many chronic diseases responsible for organ failure. Although there is currently no therapy on the market that specifically targets fibrosis, the dynamic fibrogenic process is known to be regulated by multiple soluble mediators that may be therapeutically intervened. The failing hamster heart exhibits marked fibrosis and increased expression of secreted Frizzled-related protein 2 (sFRP2) amenable to reversal by mesenchymal stem cell (MSC) therapy. Given the previous demonstration that sFRP2-null mice subjected to myocardial infarction exhibited reduced fibrosis and improved function, we tested whether antibody-based sFRP2 blockade might counteract the fibrogenic pathway and repair cardiac injury. Cardiomyopathic hamsters were injected intraperitoneally twice a week each with 20 μg of sFRP2 antibody. Echocardiography, histology, and biochemical analyses were performed after 1 mo. sFRP2 antibody increased left ventricular ejection fraction from 40 ± 1.2 to 49 ± 6.5%, whereas saline and IgG control exhibited a further decline to 37 ± 0.9 and 31 ± 3.2%, respectively. Functional improvement is associated with a ∼ 50% reduction in myocardial fibrosis, ∼ 65% decrease in apoptosis, and ∼ 75% increase in wall thickness. Consistent with attenuated fibrosis, both MSC therapy and sFRP2 antibody administration significantly increased the activity of myocardial matrix metalloproteinase-2. Gene expression analysis of the hamster heart and cultured fibroblasts identified Axin2 as a downstream target, the expression of which was activated by sFRP2 but inhibited by therapeutic intervention. sFRP2 blockade also increased myocardial levels of VEGF and hepatocyte growth factor (HGF) along with increased angiogenesis. These findings highlight the pathogenic effect of dysregulated sFRP2, which may be specifically targeted for antifibrotic therapy.

Gaze Pursuit Responses in Nucleus Reticularis Tegmenti Pontis of Head-Unrestrained Macaques

PubMed Central

Suzuki, David A.; Betelak, Kathleen F.; Yee, Robert D.

2009-01-01

Eye-head gaze pursuit–related activity was recorded in rostral portions of the nucleus reticularis tegmenti pontis (rNRTP) in alert macaques. The head was unrestrained in the horizontal plane, and macaques were trained to pursue a moving target either with their head, with the eyes stationary in the orbits, or with their eyes, with their head voluntarily held stationary in space. Head-pursuit–related modulations in rNRTP activity were observed with some cells exhibiting increases in firing rate with increases in head-pursuit frequency. For many units, this head-pursuit response appeared to saturate at higher frequencies (>0.6 Hz). The response phase re:peak head-pursuit velocity formed a continuum, containing cells that could encode head-pursuit velocity and those encoding head-pursuit acceleration. The latter cells did not exhibit head position–related activity. Sensitivities were calculated with respect to peak head-pursuit velocity and averaged 1.8 spikes/s/deg/s. Of the cells that were tested for both head- and eye-pursuit–related activity, 86% exhibited responses to both head- and eye-pursuit and therefore carried a putative gaze-pursuit signal. For these gaze-pursuit units, the ratio of head to eye response sensitivities averaged ∼1.4. Pursuit eccentricity seemed to affect head-pursuit response amplitude even in the absence of a head position response per se. The results indicated that rNRTP is a strong candidate for the source of an active head-pursuit signal that projects to the cerebellum, specifically to the target-velocity and gaze-velocity Purkinje cells that have been observed in vermal lobules VI and VII. PMID:18987125

Comparative study on the antioxidant activity of peptides from pearl oyster ( Pinctada martensii) mantle type V collagen and tilapia ( Oreochromis niloticus) scale type I collagen

NASA Astrophysics Data System (ADS)

Xia, Guanghua; Zhang, Xueying; Dong, Zhenghua; Shen, Xuanri

2017-12-01

In this study, Pearl oyster mantle type V collagen (POMC) and tilapia scale type I collagen (TSC) were extracted and hydrolyzed by various proteases in order to obtain peptides. The antioxidant activity of the peptides was investigated by DPPH, hydroxyl radical scavenging experiments and a dynamic digestion model in vitro. The results show that there are significant differences in amino acid composition between POMC and TSC. The collagen peptides obtained from pearl oyster mantle (POMCP) by treating with alkaline protease exhibited higher antioxidant activity than that from tilapia scale (TSCP) treated with papaya protease, and both of them showed greater DPPH and hydroxyl radical scavenging activity than other peptides. After being separated via Sephadex G-25 chromatography, the M1 fraction isolated from POMCP, and the S1 fraction from TSCP with which both had higher molecular weights showed the strongest antioxidant activity than other fractions, and the M1 fraction exhibited stronger antioxidant activity than the S1 fraction in scavenging free-radicals and protecting cells from the oxidation damage. Furthermore, after treating the dynamic digestion system model in vitro, the DPPH and hydroxyl radical scavenging activity of the M1 fraction increased slightly. These results suggest that POMCP exhibits stronger antioxidant activity than TSCP, which means that PMOP may be a good candidate to be a potential natural antioxidant in the food-processing industry.

Versatility of Cooperative Transcriptional Activation: A Thermodynamical Modeling Analysis for Greater-Than-Additive and Less-Than-Additive Effects

PubMed Central

Frank, Till D.; Carmody, Aimée M.; Kholodenko, Boris N.

2012-01-01

We derive a statistical model of transcriptional activation using equilibrium thermodynamics of chemical reactions. We examine to what extent this statistical model predicts synergy effects of cooperative activation of gene expression. We determine parameter domains in which greater-than-additive and less-than-additive effects are predicted for cooperative regulation by two activators. We show that the statistical approach can be used to identify different causes of synergistic greater-than-additive effects: nonlinearities of the thermostatistical transcriptional machinery and three-body interactions between RNA polymerase and two activators. In particular, our model-based analysis suggests that at low transcription factor concentrations cooperative activation cannot yield synergistic greater-than-additive effects, i.e., DNA transcription can only exhibit less-than-additive effects. Accordingly, transcriptional activity turns from synergistic greater-than-additive responses at relatively high transcription factor concentrations into less-than-additive responses at relatively low concentrations. In addition, two types of re-entrant phenomena are predicted. First, our analysis predicts that under particular circumstances transcriptional activity will feature a sequence of less-than-additive, greater-than-additive, and eventually less-than-additive effects when for fixed activator concentrations the regulatory impact of activators on the binding of RNA polymerase to the promoter increases from weak, to moderate, to strong. Second, for appropriate promoter conditions when activator concentrations are increased then the aforementioned re-entrant sequence of less-than-additive, greater-than-additive, and less-than-additive effects is predicted as well. Finally, our model-based analysis suggests that even for weak activators that individually induce only negligible increases in promoter activity, promoter activity can exhibit greater-than-additive responses when transcription factors and RNA polymerase interact by means of three-body interactions. Overall, we show that versatility of transcriptional activation is brought about by nonlinearities of transcriptional response functions and interactions between transcription factors, RNA polymerase and DNA. PMID:22506020

Acute and chronic ethanol exposure differentially alters alcohol dehydrogenase and aldehyde dehydrogenase activity in the zebrafish liver.

PubMed

Tran, Steven; Nowicki, Magda; Chatterjee, Diptendu; Gerlai, Robert

2015-01-02

Chronic ethanol exposure paradigms have been successfully used in the past to induce behavioral and central nervous system related changes in zebrafish. However, it is currently unknown whether chronic ethanol exposure alters ethanol metabolism in adult zebrafish. In the current study we examine the effect of acute ethanol exposure on adult zebrafish behavioral responses, as well as alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activity in the liver. We then examine how two different chronic ethanol exposure paradigms (continuous and repeated ethanol exposure) alter behavioral responses and liver enzyme activity during a subsequent acute ethanol challenge. Acute ethanol exposure increased locomotor activity in a dose-dependent manner. ADH activity was shown to exhibit an inverted U-shaped curve and ALDH activity was decreased by ethanol exposure at all doses. During the acute ethanol challenge, animals that were continuously housed in ethanol exhibited a significantly reduced locomotor response and increased ADH activity, however, ALDH activity did not change. Zebrafish that were repeatedly exposed to ethanol demonstrated a small but significant attenuation of the locomotor response during the acute ethanol challenge but ADH and ALDH activity was similar to controls. Overall, we identified two different chronic ethanol exposure paradigms that differentially alter behavioral and physiological responses in zebrafish. We speculate that these two paradigms may allow dissociation of central nervous system-related and liver enzyme-dependent ethanol induced changes in zebrafish. Copyright © 2014 Elsevier Inc. All rights reserved.

Research on homology modeling, molecular docking of the cellulase and highly expression of the key enzyme (Bgl) in Pichia pastoris.

PubMed

Tang, Zizhong; Jin, Weiqiong; Tang, Yujia; Wang, Yinsheng; Wang, Chang; Zheng, Xi; Sun, Wenjun; Liu, Moyang; Zheng, Tianrun; Chen, Hui; Wu, Qi; Shan, Zhi; Bu, Tongliang; Li, Chenglei

2018-08-01

Cellulose is the most abundant and renewable biological resource on earth. As nonrenewable resources are becoming scarce, cellulose is expected to become a major raw material for food, energy, fuel and other products. 1,4-β-glucosidase (Bgl), as a kind of cellulose, can be degraded cellulose into industrial available glucose. In this study, we constructed mutants of Bgl with enhanced activity based on homology modeling, molecular docking, and the site-directed mutagenesis of target residues to modify spatial positions, steric hindrances, or hydrophilicity/hydrophobicity. On the basis of the high-activity mutations were got (N347S and G235 M) by using site-directed mutagenesis and screening methods and introduced in the Pichia pastoris expression system, the enzymatic properties of mutant enzymes were analysed. Assays of the activity of the purified Bgl revealed that the two mutants exhibited increased activity. The pPICZαA-G235 M and pPICZαA-N347S mutants exhibited a >33.4% and 44.8% increase in specific activity respectively, with similar pH, temperature and metal ion requirements, compared to wild-type Bgl. These findings would be good foundation for improving production properties of Bgl in the future. Copyright © 2018 Elsevier B.V. All rights reserved.

Antioxidant Properties and Cardioprotective Mechanism of Malaysian Propolis in Rats

PubMed Central

Ahmed, Romana; Hossen, Md. Sakib; Ahmmed, Istiyak; Rumpa, Nur-E-Noushin; Sulaiman, Siti Amrah

2017-01-01

Propolis contains high concentrations of polyphenols, flavonoids, tannins, ascorbic acid, and reducing sugars and proteins. Malaysian Propolis (MP) has been reported to exhibit high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and ferric reducing antioxidant power (FRAP) values. Herein, we report the antioxidant properties and cardioprotective properties of MP in isoproterenol- (ISO-) induced myocardial infarction in rats. Male Wistar rats (n = 32) were pretreated orally with an ethanol extract of MP (100 mg/kg/day) for 30 consecutive days. Subcutaneous injection of ISO (85 mg/kg in saline) for two consecutive days caused a significant increase in serum cardiac marker enzymes and cardiac troponin I levels and altered serum lipid profiles. In addition significantly increased lipid peroxides and decreased activities of cellular antioxidant defense enzymes were observed in the myocardium. However, pretreatment of ischemic rats with MP ameliorated the biochemical parameters, indicating the protective effect of MP against ISO-induced ischemia in rats. Histopathological findings obtained for the myocardium further confirmed the biochemical findings. It is concluded that MP exhibits cardioprotective activity against ISO-induced oxidative stress through its direct cytotoxic radical-scavenging activities. It is also plausible that MP contributed to endogenous antioxidant enzyme activity via inhibition of lipid peroxidation. PMID:28261310

Preparation of Bioactive Polysaccharide Nanoparticles with Enhanced Radical Scavenging Activity and Antimicrobial Activity.

PubMed

Qin, Yang; Xiong, Liu; Li, Man; Liu, Jing; Wu, Hao; Qiu, Hongwei; Mu, Hongyan; Xu, Xingfeng; Sun, Qingjie

2018-05-02

Because of their biocompatibility and biodegradability in vivo, natural polysaccharides are effective nanocarriers for delivery of active ingredients or drugs. Moreover, bioactive polysaccharides, such as tea, Ganoderma lucidum, and Momordica charantia polysaccharides (TP, GLP, and MCP), have antibacterial, antioxidant, antitumor, and antiviral properties. In this study, tea, Ganoderma lucidum, and Momordica charantia polysaccharide nanoparticles (TP-NPs, GLP-NPs, and MCP-NPs) were prepared via the nanoprecipitation approach. When the ethanol to water ratio was 10:1, the diameter of the spherical polysaccharide nanoparticles was the smallest, and the mean particle size of the TP-NPs, GLP-NPs, and MCP-NPs was 99 ± 15, 95 ± 7, and 141 ± 9 nm, respectively. When exposed to heat, increased ionic strength and pH levels, the nanoparticles exhibited superior stability and higher activity than the corresponding polysaccharides. In physiological conditions (pH 7.4), the nanoparticles underwent different protein adsorption capacities in the following order: MCP-NPs> TP-NPs> GLP-NPs. Moreover, the 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical, and superoxide anion radical scavenging rates of the nanoparticles were increased by 9-25% as compared to the corresponding polysaccharides. Compared to the bioactive polysaccharides, the nanoparticles enhanced antimicrobial efficacy markedly and exhibited long-acting antibacterial activity.

L1 stimulation of human glioma cell motility correlates with FAK activation

PubMed Central

Yang, Muhua; Li, Yupei; Chilukuri, Kalyani; Brady, Owen A.; Boulos, Magdy I.; Kappes, John C.

2011-01-01

The neural adhesion/recognition protein L1 (L1CAM; CD171) has been shown or implicated to function in stimulation of cell motility in several cancer types, including high-grade gliomas. Our previous work demonstrated the expression and function of L1 protein in stimulation of cell motility in rat glioma cells. However, the mechanism of this stimulation is still unclear. This study further investigated the function of L1 and L1 proteolysis in human glioblastoma multiforme (GBM) cell migration and invasion, as well as the mechanism of this stimulation. L1 mRNA was found to be present in human T98G GBM cell line but not in U-118 MG grade III human glioma cell line. L1 protein expression, proteolysis, and release were found in T98G cells and human surgical GBM cells by Western blotting. Exosome-like vesicles released by T98G cells were purified and contained full-length L1. In a scratch assay, T98G cells that migrated into the denuded scratch area exhibited upregulation of ADAM10 protease expression coincident with loss of surface L1. GBM surgical specimen cells exhibited a similar loss of cell surface L1 when xenografted into the chick embryo brain. When lentivirally introduced shRNA was used to attenuate L1 expression, such T98G/shL1 cells exhibited significantly decreased cell motility by time lapse microscopy in our quantitative Super Scratch assay. These cells also showed a decrease in FAK activity and exhibited increased focal complexes. L1 binding integrins which activate FAK were found in T98G and U-118 MG cells. Addition of L1 ectodomain-containing media (1) rescued the decreased cell motility of T98G/shL1 cells and (2) increased cell motility of U-118 MG cells but (3) did not further increase T98G cell motility. Injection of L1-attenuated T98G/shL1 cells into embryonic chick brains resulted in the absence of detectable invasion compared to control cells which invaded brain tissue. These studies support a mechanism where glioma cells at the edge of a cell mass upregulate ADAM10 to proteolyze surface L1 and the resultant ectodomain increases human glioma cell migration and invasion by binding to integrin receptors, activating FAK, and increasing turnover of focal complexes. PMID:21373966

L1 stimulation of human glioma cell motility correlates with FAK activation.

PubMed

Yang, Muhua; Li, Yupei; Chilukuri, Kalyani; Brady, Owen A; Boulos, Magdy I; Kappes, John C; Galileo, Deni S

2011-10-01

The neural adhesion/recognition protein L1 (L1CAM; CD171) has been shown or implicated to function in stimulation of cell motility in several cancer types, including high-grade gliomas. Our previous work demonstrated the expression and function of L1 protein in stimulation of cell motility in rat glioma cells. However, the mechanism of this stimulation is still unclear. This study further investigated the function of L1 and L1 proteolysis in human glioblastoma multiforme (GBM) cell migration and invasion, as well as the mechanism of this stimulation. L1 mRNA was found to be present in human T98G GBM cell line but not in U-118 MG grade III human glioma cell line. L1 protein expression, proteolysis, and release were found in T98G cells and human surgical GBM cells by Western blotting. Exosome-like vesicles released by T98G cells were purified and contained full-length L1. In a scratch assay, T98G cells that migrated into the denuded scratch area exhibited upregulation of ADAM10 protease expression coincident with loss of surface L1. GBM surgical specimen cells exhibited a similar loss of cell surface L1 when xenografted into the chick embryo brain. When lentivirally introduced shRNA was used to attenuate L1 expression, such T98G/shL1 cells exhibited significantly decreased cell motility by time lapse microscopy in our quantitative Super Scratch assay. These cells also showed a decrease in FAK activity and exhibited increased focal complexes. L1 binding integrins which activate FAK were found in T98G and U-118 MG cells. Addition of L1 ectodomain-containing media (1) rescued the decreased cell motility of T98G/shL1 cells and (2) increased cell motility of U-118 MG cells but (3) did not further increase T98G cell motility. Injection of L1-attenuated T98G/shL1 cells into embryonic chick brains resulted in the absence of detectable invasion compared to control cells which invaded brain tissue. These studies support a mechanism where glioma cells at the edge of a cell mass upregulate ADAM10 to proteolyze surface L1 and the resultant ectodomain increases human glioma cell migration and invasion by binding to integrin receptors, activating FAK, and increasing turnover of focal complexes.

The apoptotic and anti-proliferative activity of Origanum majorana extracts on human leukemic cell line.

PubMed

Abdel-Massih, Roula M; Fares, Rida; Bazzi, Samer; El-Chami, Nisrine; Baydoun, Elias

2010-08-01

Scientists are constantly searching for phytochemicals and compounds with anti-cancer and antioxidant activity. In this study, the anti-proliferative activity of plant extracts from Origanum majorana (marjoram) was tested on human lymphoblastic leukemia cell line Jurkat. Cytotoxicity was examined using non-radioactive cytotoxicity assay and the IC(50) was calculated. At non-cytotoxic concentrations, the viability of cells decreased with increase of concentration of plant extract. The anti-proliferative effect was also found to be dose-dependent. Analysis via flow cytometry shows that marjoram extracts stimulated apoptosis. Induction of apoptosis was caused by an up-regulation of p53 protein levels and down-regulation of Bcl-2alpha. Marjoram exhibited a strong scavenging activity (SC(50)=0.03mg dry weight). The conclusions from this study suggest that marjoram extracts exhibit anti-proliferative effect and high antioxidant activity. For that it merits further investigation as a potential therapeutic agent. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Hollow ZSM-5 encapsulated Pt nanoparticles for selective catalytic reduction of NO by hydrogen

NASA Astrophysics Data System (ADS)

Hong, Zhe; Wang, Zhong; Chen, Dan; Sun, Qiang; Li, Xuebing

2018-05-01

Pt nanoparticles were successfully encapsulated in hollow ZSM-5 single crystals by tetrapropylammonium hydroxide (TPAOH) hydrothermal treatment with an "dissolution-recrystallization" process. The prepared Pt/hollow ZSM-5 (Pt/h-ZSM-5re) sample exhibited the best activity and a maximum NO conversion of 84% can be achieved at 90 °C with N2 selectivity of 92% (GHSV = 50,000 h-1). Meanwhile, Pt/h-ZSM-5re catalyst exhibited excellent SO2, H2O resistance and durability, which was related to the stabilization of Pt active sites by hollow structure during H2-SCR. It was found that the increase of NO2 concentration in the feed gas mixture led to an activity decline. In addition, the H2-SCR reaction routes over Pt/hollow ZSM-5 catalyst at different temperature were investigated.

CHARACTERIZATION OF A NARROW SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY AGAINST UROPATHOGENIC BACTERIA

DTIC Science & Technology

2017-08-28

NARROW-SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY AGAINST UROPATHOGENIC BACTERIA by Caitlin M. Barrows Courtney M. Cowell Jennifer...From - To) October 2015 – September 2016 4. TITLE AND SUBTITLE CHARACTERIZATION OF A NARROW-SPECTRUM ANTIMICROBIAL THAT EXHIBITS SPECIFIC ACTIVITY ...objective of the work described in this report is to identify a narrow-spectrum antimicrobial that exhibits targeted activity against uropathogenic

Effects of 60-Hz electric fields on serotonin metabolism in the rat pineal gland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, L.E.; Hilton, D.I.; Phillips, R.D.

Serotonin and two of its metabolites, melatonin and 5-methoxytryptophol, exhibit circadian rhythmicity in the pineal gland. We recently reported a marked reduction in the normal night-time increase in melatonin concentration in the pineal glands of rats exposed to 60-Hz electric fields. Concomitant with the apparent abolition of melatonin rhythmicity, serotonin-N-acetyl transferase (SNAT) activity was suppressed. We have now conducted studies to determine if abolition of the rhythm in melatonin production in electric-field-exposed rats arises solely from interference in SNAT activity, or if the availability of pineal serotonin is a factor that is affected by exposure. Pineal serotonin concentrations were comparedmore » in rats that were either exposed or sham exposed to 65 kV/m for 30 days. Sham-exposed animals exhibited normal diurnal rhythmicity for pineal concentrations of both melatonin and serotonin; melatonin levels increased markedly during the dark phase with a concurrent decrease in serotonin levels. In the exposed animals, however, normal serotonin rhythmicity was abolished; serotonin levels in these animals did not increase during the light period. The conclusion that electric field exposure results in a biochemical alteration in SNAT enzyme activity can be inferred from the loss of both serotonin and melatonin rhythmicity, as well as by direct measurement of SNAT activity itself. 35 references, 3 figures, 1 table.« less

WNT5A enhances resistance of melanoma cells to targeted BRAF inhibitors

PubMed Central

Anastas, Jamie N.; Kulikauskas, Rima M.; Tamir, Tigist; Rizos, Helen; Long, Georgina V.; von Euw, Erika M.; Yang, Pei-Tzu; Chen, Hsiao-Wang; Haydu, Lauren; Toroni, Rachel A.; Lucero, Olivia M.; Chien, Andy J.; Moon, Randall T.

2014-01-01

About half of all melanomas harbor a mutation that results in a constitutively active BRAF kinase mutant (BRAFV600E/K) that can be selectively inhibited by targeted BRAF inhibitors (BRAFis). While patients treated with BRAFis initially exhibit measurable clinical improvement, the majority of patients eventually develop drug resistance and relapse. Here, we observed marked elevation of WNT5A in a subset of tumors from patients exhibiting disease progression on BRAFi therapy. WNT5A transcript and protein were also elevated in BRAFi-resistant melanoma cell lines generated by long-term in vitro treatment with BRAFi. RNAi-mediated reduction of endogenous WNT5A in melanoma decreased cell growth, increased apoptosis in response to BRAFi challenge, and decreased the activity of prosurvival AKT signaling. Conversely, overexpression of WNT5A promoted melanoma growth, tumorigenesis, and activation of AKT signaling. Similarly to WNT5A knockdown, knockdown of the WNT receptors FZD7 and RYK inhibited growth, sensitized melanoma cells to BRAFi, and reduced AKT activation. Together, these findings suggest that chronic BRAF inhibition elevates WNT5A expression, which promotes AKT signaling through FZD7 and RYK, leading to increased growth and therapeutic resistance. Furthermore, increased WNT5A expression in BRAFi-resistant melanomas correlates with a specific transcriptional signature, which identifies potential therapeutic targets to reduce clinical BRAFi resistance. PMID:24865425

Nanosecond pulsed electric fields and the cell cycle

NASA Astrophysics Data System (ADS)

Mahlke, Megan A.

Exposure to nanosecond pulsed electrical fields (nsPEFs) can cause poration of external and internal cell membranes, DNA damage, and disassociation of cytoskeletal components, all of which are capable of disrupting a cell's ability to replicate. The phase of the cell cycle at the time of exposure is linked to differential sensitivities to nsPEFs across cell lines, as DNA structure, membrane elasticity, and cytoskeletal structure change dramatically during the cell cycle. Additionally, nsPEFs are capable of activating cell cycle checkpoints, which could lead to apoptosis or slow population growth. NsPEFs are emerging as a method for treating tumors via apoptotic induction; therefore, investigating the relevance of nsPEFs and the cell cycle could translate into improved efficacy in tumor treatment. Populations of Jurkat and Chinese Hamster Ovary (CHO) cells were examined post-exposure (10 ns pulse trains at 150kV/cm) by analysis of DNA content via propidium iodide staining and flow cytometric analysis at various time points (1, 6, and 12h post-exposure) to determine population distribution in cell cycle phases. Additionally, CHO and Jurkat cells were synchronized in G1/S and G2/M phases, pulsed, and analyzed to evaluate the role of cell cycle phase in survival of nsPEFs. CHO populations appeared similar to sham populations post-nsPEFs but exhibited arrest in the G1 phase at 6h after exposure. Jurkat cells exhibited increased cell death after nsPEFs compared to CHO cells but did not exhibit checkpoint arrest at any observed time point. The G1/S phase checkpoint is partially controlled by the action of p53; the lack of an active p53 response in Jurkat cells could contribute to their ability to pass this checkpoint and resist cell cycle arrest. Both cell lines exhibited increased sensitivity to nsPEFs in G2/M phase. Live imaging of CHO cells after nsPEF exposure supports the theory of G1/S phase arrest, as a reduced number of cells undergo mitosis within 24 h when compared to sham treated cells. CHO cells undergoing mitosis after exposure also exhibit improper separation of chromatids which could indicate loss of function of the mitotic spindle checkpoint. Activation and loss of function of checkpoints in CHO but not Jurkat cells after nsPEF exposure suggests that activation of cell cycle checkpoints could be important in defining the character of cell line specific recovery after nsPEF exposure. Moreover, the increased sensitivity in G2/M phase exhibited by both cell lines indicates that cell cycle phase is an important consideration during nsPEF exposure, particularly when aiming to induce apoptosis.

Spatial distribution and expression of intracellular and extracellular acid phosphatases of cluster roots at different developmental stages in white lupin.

PubMed

Tang, Hongliang; Li, Xiaoqing; Zu, Chao; Zhang, Fusuo; Shen, Jianbo

2013-09-15

Acid phosphatases (APases) play a key role in phosphorus (P) acquisition and recycling in plants. White lupin (Lupinus albus L.) forms cluster roots (CRs) and produces large amounts of APases under P deficiency. However, the relationships between the activity of intracellular and extracellular APases (EC 3.1.3.2) and CR development are not fully understood. Here, comparative studies were conducted to examine the spatial variation pattern of APase activity during CR development using the enzyme-labelled fluorescence-97 (ELF-97) and the p-nitrophenyl phosphate methods. The activity of intracellular and extracellular APases was significantly enhanced under P deficiency in the non-CRs and CRs at different developmental stages. These two APases exhibited different spatial distribution patterns during CR development, and these distribution patterns were highly modified by P deficiency. The activity of extracellular APase increased steadily with CR development from meristematic, juvenile, mature to senescent stages under P deficiency. In comparison, P deficiency-induced increase in the activity of intracellular APase remained relatively constant during CR development. Increased activity of intracellular and extracellular APases was associated with enhanced expression of LaSAP1 encoding intracellular APase and LaSAP2 encoding extracellular APase. The expression levels of these two genes were significantly higher at transcriptional level in both mature and senescent CRs. Taken together, these findings demonstrate that both activity and gene expression of intracellular or extracellular APases exhibit a differential response pattern during CR development, depending on root types, CR developmental stages and P supply. Simultaneous in situ determination of intracellular and extracellular APase activity has proved to be an effective approach for studying spatial variation of APases during CR development. Copyright © 2013 Elsevier GmbH. All rights reserved.

Adaptive response of rat pancreatic β-cells to insulin resistance induced by monocrotophos: Biochemical evidence.

PubMed

Nagaraju, Raju; Rajini, Padmanabhan Sharda

2016-11-01

Our previous findings clearly suggested the role of duration of exposure to monocrotophos (MCP) in the development of insulin resistance. Rats exposed chronically to MCP developed insulin resistance with hyperinsulinemia without overt diabetes. In continuation of this vital observation, we sought to delineate the biochemical mechanisms that mediate heightened pancreatic β-cell response in the wake of MCP-induced insulin resistance in rats. Adult rats were orally administered (0.9 and 1.8mg/kgb.w/d) MCP for 180days. Terminally, MCP-treated rats exhibited glucose intolerance, hyperinsulinemia, and potentiation of glucose-induced insulin secretion along with elevated levels of circulating IGF1, free fatty acids, corticosterone, and paraoxonase activity. Biochemical analysis of islet extracts revealed increased levels of insulin, malate, pyruvate and ATP with a concomitant increase in activities of cytosolic and mitochondrial enzymes that are known to facilitate insulin secretion and enhanced shuttle activities. Interestingly, islets from MCP-treated rats exhibited increased insulin secretory potential ex vivo compared to those isolated from control rats. Further, MCP-induced islet hypertrophy was associated with increased insulin-positive cells. Our study demonstrates the impact of the biological interaction between MCP and components of metabolic homeostasis on pancreatic beta cell function/s. We speculate that the heightened pancreatic beta cell function evidenced may be mediated by increased IGF1 and paraoxonase activity, which effectively counters insulin resistance induced by chronic exposure to MCP. Our findings emphasize the need for focused research to understand the confounding environmental risk factors which may modulate heightened beta cell functions in the case of organophosphorus insecticide-induced insulin resistance. Such an approach may help us to explain the sharp increase in the prevalence of type II diabetes worldwide. Copyright © 2016 Elsevier B.V. All rights reserved.

Exploring the Effects of Active Learning on Retaining Essential Concepts in Secondary and Junior High Classrooms

ERIC Educational Resources Information Center

Bachelor, Robin L.; Vaughan, Patrick M.; Wall, Connie M.

2012-01-01

This report describes a program for improving retention of essential concepts exhibited by junior high and high school students. The purpose of the study was to increase cognitive retention in order to increase student success. The target sample consisted of junior high students in the seventh grade and high school students in grades nine through…

Pharmacokinetics and dromotropic activity of ajmaline in rats with hyperthyroidism.

PubMed Central

Hashimoto, Y.; Yasuhara, M.; Kamiya, A.; Okumura, K.; Hori, R.

1989-01-01

1. The pharmacokinetics and the dromotropic action (increased PQ interval) of intravenously administered ajmaline (2 mg kg-1) were studied in hyperthyroid rats with sinus tachycardia. The hyperthyroidism was induced by intraperitoneal injection of 3,5,3'-triiodo-L-thyronine (0.5 mg kg-1) for 4 days. 2. The change in the ajmaline concentration in whole blood could be described by a biexponential equation. The steady state distribution volume of ajmaline decreased from 4.81 l kg-1 in control rats to 3.80 l kg-1 in hyperthyroid rats and the total body blood clearance was slightly higher in hyperthyroid rats than in control rats. 3. Ajmaline exhibited a saturable binding to rat plasma proteins, and one kind of binding site was found in the observed range of concentrations. The binding capacity was 2 fold higher in hyperthyroid rats than in control rats. 4. On the basis of the plasma unbound concentration, ajmaline exhibited an increased negative dromotropic activity in hyperthyroid rats compared with control rats. 5. A positive correlation was found between the pacing rate and the dromotropic action of ajmaline on atrioventricular conduction in isolated perfused hearts. There was no significant difference in the rate-dependence of the effect of ajmaline on the heart between control and hyperthyroid rats. 6. Our findings suggest that the increased dromotropic activity of ajmaline is mainly due to the increased heart rate in hyperthyroid rats. PMID:2924068

Impacts of visitor number on Kangaroos housed in free-range exhibits.

PubMed

Sherwen, Sally L; Hemsworth, Paul H; Butler, Kym L; Fanson, Kerry V; Magrath, Michael J L

2015-01-01

Free range exhibits are becoming increasingly popular in zoos as a means to enhance interaction between visitors and animals. However very little research exists on the impacts of visitors on animal behaviour and stress in free range exhibits. We investigated the effects of visitor number on the behaviour and stress physiology of Kangaroo Island (KI) Kangaroos, Macropus fuliginosus fuliginosus, and Red Kangaroos, Macropus rufus, housed in two free range exhibits in Australian zoos. Behavioural observations were conducted on individual kangaroos at each site using instantaneous scan sampling to record activity (e.g., vigilance, foraging, resting) and distance from the visitor pathway. Individually identifiable faecal samples were collected at the end of each study day and analysed for faecal glucocorticoid metabolite (FGM) concentration. When visitor number increased, both KI Kangaroos and Red Kangaroos increased the time spent engaged in visitor-directed vigilance and KI Kangaroos also increased the time spent engaged in locomotion and decreased the time spent resting. There was no effect of visitor number on the distance kangaroos positioned themselves from the visitor pathway or FGM concentration in either species. While there are limitations in interpreting these results in terms of fear of visitors, there was no evidence of adverse effects animal welfare in these study groups based on avoidance behaviour or stress physiology under the range of visitor numbers that we studied. © 2015 Wiley Periodicals, Inc.

EEG in 1-Week, 1-Month and 3-Month-Old Infants of Depressed and Non-Depressed Mothers

PubMed Central

Diego, Miguel A.; Jones, Nancy Aaron; Field, Tiffany

2010-01-01

EEGs were examined in data collected from 348 1-week, 1-month and 3-month-old infants of depressed and non-depressed mothers across several studies. Both the percentage of infants exhibiting spectral peaks and the frequency in Hz at which those peaks were exhibited increased with age. Consistent with previous studies, infants of depressed mothers exhibited greater left frontal EEG power, suggesting greater relative right frontal EEG activity than infants of non-depressed mothers. This profile was apparent across a narrow frequency range, which shifted from 3–9Hz at one week of age to 4–9Hz by three months of age. PMID:19782119

Adaptive significance of right hemisphere activation in aphasic language comprehension

PubMed Central

Meltzer, Jed A.; Wagage, Suraji; Ryder, Jennifer; Solomon, Beth; Braun, Allen R.

2013-01-01

Aphasic patients often exhibit increased right hemisphere activity during language tasks. This may represent takeover of function by regions homologous to the left-hemisphere language networks, maladaptive interference, or adaptation of alternate compensatory strategies. To distinguish between these accounts, we tested language comprehension in 25 aphasic patients using an online sentence-picture matching paradigm while measuring brain activation with MEG. Linguistic conditions included semantically irreversible (“The boy is eating the apple”) and reversible (“The boy is pushing the girl”) sentences at three levels of syntactic complexity. As expected, patients performed well above chance on irreversible sentences, and at chance on reversible sentences of high complexity. Comprehension of reversible non-complex sentences ranged from nearly perfect to chance, and was highly correlated with offline measures of language comprehension. Lesion analysis revealed that comprehension deficits for reversible sentences were predicted by damage to the left temporal lobe. Although aphasic patients activated homologous areas in the right temporal lobe, such activation was not correlated with comprehension performance. Rather, patients with better comprehension exhibited increased activity in dorsal fronto-parietal regions. Correlations between performance and dorsal network activity occurred bilaterally during perception of sentences, and in the right hemisphere during a post-sentence memory delay. These results suggest that effortful reprocessing of perceived sentences in short-term memory can support improved comprehension in aphasia, and that strategic recruitment of alternative networks, rather than homologous takeover, may account for some findings of right hemisphere language activation in aphasia. PMID:23566891

Novel repair activities of AlkA (3-methyladenine DNA glycosylase II) and endonuclease VIII for xanthine and oxanine, guanine lesions induced by nitric oxide and nitrous acid

PubMed Central

Terato, Hiroaki; Masaoka, Aya; Asagoshi, Kenjiro; Honsho, Akiko; Ohyama, Yoshihiko; Suzuki, Toshinori; Yamada, Masaki; Makino, Keisuke; Yamamoto, Kazuo; Ide, Hiroshi

2002-01-01

Nitrosation of guanine in DNA by nitrogen oxides such as nitric oxide (NO) and nitrous acid leads to formation of xanthine (Xan) and oxanine (Oxa), potentially cytotoxic and mutagenic lesions. In the present study, we have examined the repair capacity of DNA N-glycosylases from Escherichia coli for Xan and Oxa. The nicking assay with the defined substrates containing Xan and Oxa revealed that AlkA [in combination with endonuclease (Endo) IV] and Endo VIII recognized Xan in the tested enzymes. The activity (Vmax/Km) of AlkA for Xan was 5-fold lower than that for 7-methylguanine, and that of Endo VIII was 50-fold lower than that for thymine glycol. The activity of AlkA and Endo VIII for Xan was further substantiated by the release of [3H]Xan from the substrate. The treatment of E.coli with N-methyl-N′-nitro-N-nitrosoguanidine increased the Xan-excising activity in the cell extract from alkA+ but not alkA– strains. The alkA and nei (the Endo VIII gene) double mutant, but not the single mutants, exhibited increased sensitivity to nitrous acid relative to the wild type strain. AlkA and Endo VIII also exhibited excision activity for Oxa, but the activity was much lower than that for Xan. PMID:12434002

Structure and activity of the Pseudomonas aeruginosa hotdog-fold thioesterases PA5202 and PA2801

PubMed Central

Gonzalez, Claudio F.; Tchigvintsev, Anatoli; Brown, Greg; Flick, Robert; Evdokimova, Elena; Xu, Xiaohui; Osipiuk, Jerzy; Cuff, Marianne E.; Lynch, Susan; Joachimiak, Andrzej; Savchenko, Alexei; Yakunin, Alexander F.

2013-01-01

The hotdog fold is one of the basic protein folds widely present in bacteria, archaea, and eukaryotes. Many of these proteins exhibit thioesterase activity against fatty acyl-CoAs and play important roles in lipid metabolism, cellular signaling, and degradation of xenobiotics. The genome of the opportunistic pathogen Pseudomonas aeruginosa contains over 20 genes encoding predicted hotdog-fold proteins, none of which have been experimentally characterized. We have found that two P. aeruginosa hotdog proteins display high thioesterase activity against 3-hydroxy-3-methylglutaryl-CoA and glutaryl-CoA (PA5202), and octanoyl-CoA (PA2801). Crystal structures of these proteins were solved (1.70 and 1.75 Å) and revealed a hotdog fold with a potential catalytic carboxylate residue located on the long alpha helix (Asp57 in PA5202 and Glu35 in PA2801). Alanine replacement mutagenesis of PA5202 identified four residues (Asn42, Arg43, Asp57, and Thr76), which are critical for activity and are located in the active site. A P. aeruginosa PA5202 deletion strain showed an increased secretion of the antimicrobial pigment pyocyanine and an increased expression of genes involved in pyocyanin biosynthesis suggesting a functional link between the PA5202 activity and pyocyanin production. Thus, the P. aeruginosa hotdog thioesterases PA5202 and PA2801 have similar structures, but exhibit different substrate preferences and functions. PMID:22439787

77 FR 52246 - Clothianidin; Pesticide Tolerances

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-29

... concern. Clinical signs of neurotoxicity were exhibited in both rats (decreased arousal, motor activity..., delayed sexual maturation and an increase in stillbirths) was observed in the absence of maternal effects... weight gains and FQPA SF = 1X........ day. delayed sexual maturation, decreased absolute thymus weights...

Exercise recommendations for individuals with spinal cord injury.

PubMed

Jacobs, Patrick L; Nash, Mark S

2004-01-01

Persons with spinal cord injury (SCI) exhibit deficits in volitional motor control and sensation that limit not only the performance of daily tasks but also the overall activity level of these persons. This population has been characterised as extremely sedentary with an increased incidence of secondary complications including diabetes mellitus, hypertension and atherogenic lipid profiles. As the daily lifestyle of the average person with SCI is without adequate stress for conditioning purposes, structured exercise activities must be added to the regular schedule if the individual is to reduce the likelihood of secondary complications and/or to enhance their physical capacity. The acute exercise responses and the capacity for exercise conditioning are directly related to the level and completeness of the spinal lesion. Appropriate exercise testing and training of persons with SCI should be based on the individual's exercise capacity as determined by accurate assessment of the spinal lesion. The standard means of classification of SCI is by application of the International Standards for Classification of Spinal Cord Injury, written by the Neurological Standards Committee of the American Spinal Injury Association. Individuals with complete spinal injuries at or above the fourth thoracic level generally exhibit dramatically diminished cardiac acceleration with maximal heart rates less than 130 beats/min. The work capacity of these persons will be limited by reductions in cardiac output and circulation to the exercising musculature. Persons with complete spinal lesions below the T(10) level will generally display injuries to the lower motor neurons within the lower extremities and, therefore, will not retain the capacity for neuromuscular activation by means of electrical stimulation. Persons with paraplegia also exhibit reduced exercise capacity and increased heart rate responses (compared with the non-disabled), which have been associated with circulatory limitations within the paralysed tissues. The recommendations for endurance and strength training in persons with SCI do not vary dramatically from the advice offered to the general population. Systems of functional electrical stimulation activate muscular contractions within the paralysed muscles of some persons with SCI. Coordinated patterns of stimulation allows purposeful exercise movements including recumbent cycling, rowing and upright ambulation. Exercise activity in persons with SCI is not without risks, with increased risks related to systemic dysfunction following the spinal injury. These individuals may exhibit an autonomic dysreflexia, significantly reduced bone density below the spinal lesion, joint contractures and/or thermal dysregulation. Persons with SCI can benefit greatly by participation in exercise activities, but those benefits can be enhanced and the relative risks may be reduced with accurate classification of the spinal injury.

Polyphenolic Extract from Maple Syrup Potentiates Antibiotic Susceptibility and Reduces Biofilm Formation of Pathogenic Bacteria

PubMed Central

Maisuria, Vimal B.; Hosseinidoust, Zeinab

2015-01-01

Phenolic compounds are believed to be promising candidates as complementary therapeutics. Maple syrup, prepared by concentrating the sap from the North American maple tree, is a rich source of natural and process-derived phenolic compounds. In this work, we report the antimicrobial activity of a phenolic-rich maple syrup extract (PRMSE). PRMSE exhibited antimicrobial activity as well as strong synergistic interaction with selected antibiotics against Gram-negative clinical strains of Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa. Among the phenolic constituents of PRMSE, catechol exhibited strong synergy with antibiotics as well as with other phenolic components of PRMSE against bacterial growth. At sublethal concentrations, PRMSE and catechol efficiently reduced biofilm formation and increased the susceptibility of bacterial biofilms to antibiotics. In an effort to elucidate the mechanism for the observed synergy with antibiotics, PRMSE was found to increase outer membrane permeability of all bacterial strains and effectively inhibit efflux pump activity. Furthermore, transcriptome analysis revealed that PRMSE significantly repressed multiple-drug resistance genes as well as genes associated with motility, adhesion, biofilm formation, and virulence. Overall, this study provides a proof of concept and starting point for investigating the molecular mechanism of the reported increase in bacterial antibiotic susceptibility in the presence of PRMSE. PMID:25819960

Polyphenolic extract from maple syrup potentiates antibiotic susceptibility and reduces biofilm formation of pathogenic bacteria.

PubMed

Maisuria, Vimal B; Hosseinidoust, Zeinab; Tufenkji, Nathalie

2015-06-01

Phenolic compounds are believed to be promising candidates as complementary therapeutics. Maple syrup, prepared by concentrating the sap from the North American maple tree, is a rich source of natural and process-derived phenolic compounds. In this work, we report the antimicrobial activity of a phenolic-rich maple syrup extract (PRMSE). PRMSE exhibited antimicrobial activity as well as strong synergistic interaction with selected antibiotics against Gram-negative clinical strains of Escherichia coli, Proteus mirabilis, and Pseudomonas aeruginosa. Among the phenolic constituents of PRMSE, catechol exhibited strong synergy with antibiotics as well as with other phenolic components of PRMSE against bacterial growth. At sublethal concentrations, PRMSE and catechol efficiently reduced biofilm formation and increased the susceptibility of bacterial biofilms to antibiotics. In an effort to elucidate the mechanism for the observed synergy with antibiotics, PRMSE was found to increase outer membrane permeability of all bacterial strains and effectively inhibit efflux pump activity. Furthermore, transcriptome analysis revealed that PRMSE significantly repressed multiple-drug resistance genes as well as genes associated with motility, adhesion, biofilm formation, and virulence. Overall, this study provides a proof of concept and starting point for investigating the molecular mechanism of the reported increase in bacterial antibiotic susceptibility in the presence of PRMSE. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The “gating” residues Ile199 and Tyr326 in human monoamine oxidase B function in substrate and inhibitor recognition

PubMed Central

Milczek, Erika M.; Binda, Claudia; Rovida, Stefano; Mattevi, Andrea; Edmondson, Dale E.

2011-01-01

Summary The major structural difference between human monoamine oxidases A (MAO A) and B (MAO B) is that MAO A has a monopartite substrate cavity of ~550 Å3 volume and MAO B contains a dipartite cavity structure with volumes of ~290 Å3 (entrance cavity) and ~400 Å3 (substrate cavity). Ile199 and Tyr326 side chains separate these two cavities in MAO B. To probe the function of these gating residues, Ile199Ala and Ile199Ala Tyr326Ala mutant forms of MAO B were investigated. Structural data on the Ile199Ala MAO B mutant show no alterations in active site geometries compared to WT enzyme while the Ile199Ala-Tyr326Ala MAO B mutant exhibits alterations in residues 100–103 which are part of the loop gating the entrance to the active site. Both mutant enzymes exhibit catalytic properties with increased amine KM but unaltered kcat values. The altered KM values on mutation are attributed to the influence of the cavity structure in the binding and subsequent deprotonation of the amine substrate. Both mutant enzymes exhibit weaker binding affinities relative to WT enzyme for small reversible inhibitors. Ile199Ala MAO B exhibits an increase in binding affinity for reversible MAO B specific inhibitors which bridge both cavities. The Ile199Ala-Tyr326Ala double mutant exhibits inhibitor binding properties more similar to those of MAO A than to MAO B. These results demonstrate the bipartite cavity structure in MAO B plays an important role in substrate and inhibitor recognition to distinguish its specificities from those of MAO A and provides insights into specific reversible inhibitor design for these membrane-bound enzymes. PMID:21978362

Fluorinated alkyl substances and technical mixtures used in food paper-packaging exhibit endocrine-related activity in vitro.

PubMed

Rosenmai, A K; Taxvig, C; Svingen, T; Trier, X; van Vugt-Lussenburg, B M A; Pedersen, M; Lesné, L; Jégou, B; Vinggaard, A M

2016-07-01

Migration of chemicals from packaging materials to foods may lead to human exposure. Polyfluoroalkyl substances (PFAS) can be used in technical mixtures (TMs) for use in food packaging of paper and board, and PFAS have been detected in human serum and umbilical cord blood. The specific structures of the PFAS in TMs are often unknown, but polyfluorinated alkyl phosphate esters (PAPs) have been characterized in TMs, food packaging, and in food. PAPs can be metabolized into fluorotelomer alcohols (FTOHs) and perfluoroalkyl carboxylic acids (PFCAs). Some PFAS have endocrine activities, highlighting the need to investigate these effects. Herein, we studied the endocrine activity of less characterized PFAS, including short-chain PFCAs and FTOHs, PAPs, and TMs of unknown chemical composition. Long-chain PFCAs were also included. We applied seven assays covering effects on estrogen, glucocorticoid, androgen, and peroxisome proliferator-activated receptor (PPAR) activity, as well as steroidogenesis in vitro and ex vivo. In general, PAPs, FTOHs, TMs, and long-chain PFCAs showed estrogenic activity through receptor activation and/or increasing 17β-estradiol levels. Furthermore, short- and long-chain PFCAs activated PPARα and PPARγ. Collectively, this means that (i) PAPs, FTOHs, and PFCAs exhibit endocrine activity through distinct and sometimes different mechanisms, (ii) two out of three tested TMs exhibited estrogenic activity, and (iii) short-chain FTOHs showed estrogenic activity and short-chain PFCAs generally activate both PPARα and PPARγ with similar potency and efficacy as long-chain PFCAs. In conclusion, several new and divergent toxicological targets were identified for different groups of PFAS. © 2016 American Society of Andrology and European Academy of Andrology.

The Influence of Load and Speed on Individuals' Movement Behavior.

PubMed

Frost, David M; Beach, Tyson A C; Callaghan, Jack P; McGill, Stuart M

2015-09-01

Because individuals' movement patterns have been linked to their risk of future injury, movement evaluations have become a topic of interest. However, if individuals adapt their movement behavior in response to the demands of a task, the utility of evaluations comprising only low-demand activities could have limited application with regard to the prediction of future injury. This investigation examined the impact of load and speed on individuals' movement behavior. Fifty-two firefighters performed 5 low-demand (i.e., light load, low movement speed) whole-body tasks (i.e., lift, squat, lunge, push, and pull). Each task was then modified by increasing the speed, external load, or speed and load. Select measures of motion were used to characterize the performance of each task, and comparisons were made between conditions. The participants adapted their movement behavior in response to the external demands of a task (64 and 70% of all the variables were influenced [p ≤ 0.05] by changing the load and speed, respectively), but in a manner unique to the task and type of demand. The participants exhibited greater spine and frontal plane knee motion in response to an increase in speed when compared with increasing loads. However, there were a large number of movement strategies exhibited by individual firefighters that differed from the group's response. The data obtained here imply that individuals may not be physically prepared to perform safely or effectively when a task's demands are elevated simply because they exhibit the ability to perform a low-demand activity with competence. Therefore, movement screens comprising only low-demand activities may not adequately reflect an individual's capacity, or their risk of injury, and could adversely affect any recommendations that are made for training or job performance.

Type 3 Deiodinase Role on Central Thyroid Hormone Action Affects the Leptin-Melanocortin System and Circadian Activity

PubMed Central

Wu, Zhaofei; Martinez, M. Elena; St. Germain, Donald L.

2017-01-01

The role of thyroid hormones (THs) in the central regulation of energy balance is increasingly appreciated. Mice lacking the type 3 deiodinase (DIO3), which inactivates TH, have decreased circulating TH levels relative to control mice as a result of defects in the hypothalamic-pituitary-thyroid axis. However, we have shown that the TH status of the adult Dio3−/− brain is opposite that of the serum, exhibiting enhanced levels of TH action. Because the brain, particularly the hypothalamus, harbors important circuitries that regulate metabolism, we aimed to examine the energy balance phenotype of Dio3−/− mice and determine whether it is associated with hypothalamic abnormalities. Here we show that Dio3−/− mice of both sexes exhibit decreased adiposity, reduced brown and white adipocyte size, and enhanced fat loss in response to triiodothyronine (T3) treatment. They also exhibit increased TH action in the hypothalamus, with abnormal expression and T3 sensitivity of genes integral to the leptin-melanocortin system, including Agrp, Npy, Pomc, and Mc4r. The normal to elevated serum levels of leptin, and elevated and repressed expression of Agrp and Pomc, respectively, suggest a profile of leptin resistance. Interestingly, Dio3−/− mice also display elevated locomotor activity and increased energy expenditure. This occurs in association with expanded nighttime activity periods, suggesting a disrupted circadian rhythm. We conclude that DIO3-mediated regulation of TH action in the central nervous system influences multiple critical determinants of energy balance. Those influences may partially compensate each other, with the result likely contributing to the decreased adiposity observed in Dio3−/− mice. PMID:27911598

Type 3 Deiodinase Role on Central Thyroid Hormone Action Affects the Leptin-Melanocortin System and Circadian Activity.

PubMed

Wu, Zhaofei; Martinez, M Elena; St Germain, Donald L; Hernandez, Arturo

2017-02-01

The role of thyroid hormones (THs) in the central regulation of energy balance is increasingly appreciated. Mice lacking the type 3 deiodinase (DIO3), which inactivates TH, have decreased circulating TH levels relative to control mice as a result of defects in the hypothalamic-pituitary-thyroid axis. However, we have shown that the TH status of the adult Dio3-/- brain is opposite that of the serum, exhibiting enhanced levels of TH action. Because the brain, particularly the hypothalamus, harbors important circuitries that regulate metabolism, we aimed to examine the energy balance phenotype of Dio3-/- mice and determine whether it is associated with hypothalamic abnormalities. Here we show that Dio3-/- mice of both sexes exhibit decreased adiposity, reduced brown and white adipocyte size, and enhanced fat loss in response to triiodothyronine (T3) treatment. They also exhibit increased TH action in the hypothalamus, with abnormal expression and T3 sensitivity of genes integral to the leptin-melanocortin system, including Agrp, Npy, Pomc, and Mc4r. The normal to elevated serum levels of leptin, and elevated and repressed expression of Agrp and Pomc, respectively, suggest a profile of leptin resistance. Interestingly, Dio3-/- mice also display elevated locomotor activity and increased energy expenditure. This occurs in association with expanded nighttime activity periods, suggesting a disrupted circadian rhythm. We conclude that DIO3-mediated regulation of TH action in the central nervous system influences multiple critical determinants of energy balance. Those influences may partially compensate each other, with the result likely contributing to the decreased adiposity observed in Dio3-/- mice. Copyright © 2017 by the Endocrine Society.

Reflection of the State of Hunger in Impulse Activity of Nose Wing Muscles and Upper Esophageal Sphincter during Search behavior in Rabbits.

PubMed

Kromin, A A; Dvoenko, E E; Zenina, O Yu

2016-07-01

Reflection of the state of hunger in impulse activity of nose wing muscles and upper esophageal sphincter muscles was studied in chronic experiments on rabbits subjected to 24-h food deprivation in the absence of locomotion and during search behavior. In the absence of apparent behavioral activity, including sniffing, alai nasi muscles of hungry rabbits constantly generated bursts of action potentials synchronous with breathing, while upper esophageal sphincter muscles exhibited regular aperiodic low-amplitude impulse activity of tonic type. Latent form of food motivation was reflected in the structure of temporal organization of impulse activity of alai nasi muscles in the form of bimodal distribution of interpulse intervals and in temporal structure of impulse activity of upper esophageal sphincter muscles in the form of monomodal distribution. The latent form of food motivation was manifested in the structure of temporal organization of periods of the action potentials burst-like rhythm, generated by alai nasi muscles, in the form of monomodal distribution, characterized by a high degree of dispersion of respiratory cycle periods. In the absence of physical activity hungry animals sporadically exhibited sniffing activity, manifested in the change from the burst-like impulse activity of alai nasi muscles to the single-burst activity type with bimodal distribution of interpulse intervals and monomodal distribution of the burst-like action potentials rhythm periods, the maximum of which was shifted towards lower values, which was the cause of increased respiratory rate. At the same time, the monomodal temporal structure of impulse activity of the upper esophageal sphincter muscles was not changed. With increasing food motivation in the process of search behavior temporal structure of periods of the burst-like action potentials rhythm, generated by alai nasi muscles, became similar to that observed during sniffing, not accompanied by animal's locomotion, which is typical for the increased respiratory rhythm frequency. Increased hunger motivation was reflected in the temporal structure of impulse activity of upper esophageal sphincter muscles in the form of a shift to lower values of the maximum of monomodal distribution of interpulse intervals on the histogram, resulting in higher impulse activity frequency. The simultaneous increase in the frequency of action potentials bursts generation by alai nasi muscles and regular impulse activity of upper esophageal sphincter muscles is a reliable criterion for enhanced food motivation during search behavior in rabbits.

A687V EZH2 is a driver of histone H3 lysine 27 (H3K27) hypertrimethylation.

PubMed

Ott, Heidi M; Graves, Alan P; Pappalardi, Melissa B; Huddleston, Michael; Halsey, Wendy S; Hughes, Ashley M; Groy, Arthur; Dul, Edward; Jiang, Yong; Bai, Yuchen; Annan, Roland; Verma, Sharad K; Knight, Steven D; Kruger, Ryan G; Dhanak, Dashyant; Schwartz, Benjamin; Tummino, Peter J; Creasy, Caretha L; McCabe, Michael T

2014-12-01

The EZH2 methyltransferase silences gene expression through methylation of histone H3 on lysine 27 (H3K27). Recently, EZH2 mutations have been reported at Y641, A677, and A687 in non-Hodgkin lymphoma. Although the Y641F/N/S/H/C and A677G mutations exhibit clearly increased activity with substrates dimethylated at lysine 27 (H3K27me2), the A687V mutant has been shown to prefer a monomethylated lysine 27 (H3K27me1) with little gain of activity toward H3K27me2. Herein, we demonstrate that despite this unique substrate preference, A687V EZH2 still drives increased H3K27me3 when transiently expressed in cells. However, unlike the previously described mutants that dramatically deplete global H3K27me2 levels, A687V EZH2 retains normal levels of H3K27me2. Sequencing of B-cell-derived cancer cell lines identified an acute lymphoblastic leukemia cell line harboring this mutation. Similar to exogenous expression of A687V EZH2, this cell line exhibited elevated H3K27me3 while possessing H3K27me2 levels higher than Y641- or A677-mutant lines. Treatment of A687V EZH2-mutant cells with GSK126, a selective EZH2 inhibitor, was associated with a global decrease in H3K27me3, robust gene activation, caspase activation, and decreased proliferation. Structural modeling of the A687V EZH2 active site suggests that the increased catalytic activity with H3K27me1 may be due to a weakened interaction with an active site water molecule that must be displaced for dimethylation to occur. These findings suggest that A687V EZH2 likely increases global H3K27me3 indirectly through increased catalytic activity with H3K27me1 and cells harboring this mutation are highly dependent on EZH2 activity for their survival. ©2014 American Association for Cancer Research.

Decreased resting-state brain activity complexity in schizophrenia characterized by both increased regularity and randomness.

PubMed

Yang, Albert C; Hong, Chen-Jee; Liou, Yin-Jay; Huang, Kai-Lin; Huang, Chu-Chung; Liu, Mu-En; Lo, Men-Tzung; Huang, Norden E; Peng, Chung-Kang; Lin, Ching-Po; Tsai, Shih-Jen

2015-06-01

Schizophrenia is characterized by heterogeneous pathophysiology. Using multiscale entropy (MSE) analysis, which enables capturing complex dynamics of time series, we characterized MSE patterns of blood-oxygen-level-dependent (BOLD) signals across different time scales and determined whether BOLD activity in patients with schizophrenia exhibits increased complexity (increased entropy in all time scales), decreased complexity toward regularity (decreased entropy in all time scales), or decreased complexity toward uncorrelated randomness (high entropy in short time scales followed by decayed entropy as the time scale increases). We recruited 105 patients with schizophrenia with an age of onset between 18 and 35 years and 210 age- and sex-matched healthy volunteers. Results showed that MSE of BOLD signals in patients with schizophrenia exhibited two routes of decreased BOLD complexity toward either regular or random patterns. Reduced BOLD complexity toward regular patterns was observed in the cerebellum and temporal, middle, and superior frontal regions, and reduced BOLD complexity toward randomness was observed extensively in the inferior frontal, occipital, and postcentral cortices as well as in the insula and middle cingulum. Furthermore, we determined that the two types of complexity change were associated differently with psychopathology; specifically, the regular type of BOLD complexity change was associated with positive symptoms of schizophrenia, whereas the randomness type of BOLD complexity was associated with negative symptoms of the illness. These results collectively suggested that resting-state dynamics in schizophrenia exhibit two routes of pathologic change toward regular or random patterns, which contribute to the differences in syndrome domains of psychosis in patients with schizophrenia. © 2015 Wiley Periodicals, Inc.

"small problems, Big Trouble": An Art and Science Collaborative Exhibition Reflecting Seemingly small problems Leading to Big Threats

NASA Astrophysics Data System (ADS)

Waller, J. L.; Brey, J. A.

2014-12-01

"small problems, Big Trouble" (spBT) is an exhibition of artist Judith Waller's paintings accompanied by text panels written by Earth scientist Dr. James A. Brey and several science researchers and educators. The text panels' message is as much the focus of the show as the art--true interdisciplinarity! Waller and Brey's history of art and earth science collaborations include the successful exhibition "Layers: Places in Peril". New in spBT is extended collaboration with other scientists in order to create awareness of geoscience and other subjects (i.e. soil, parasites, dust, pollutants, invasive species, carbon, ground water contaminants, solar wind) small in scale which pose significant threats. The paintings are the size of a mirror, a symbol suggesting the problems depicted are those we increasingly need to face, noting our collective reflections of shared current and future reality. Naturalistic rendering and abstract form in the art helps reach a broad audience including those familiar with art and those familiar with science. The goal is that gallery visitors gain greater appreciation and understanding of both—and of the sober content of the show as a whole. "small problems, Big Trouble" premiers in Wisconsin April, 2015. As in previous collaborations, Waller and Brey actively utilize art and science (specifically geoscience) as an educational vehicle for active student learning. Planned are interdisciplinary university and area high school activities linked through spBT. The exhibition in a public gallery offers a means to enhance community awareness of and action on scientific issues through art's power to engage people on an emotional level. This AGU presentation includes a description of past Waller and Brey activities: incorporating art and earth science in lab and studio classrooms, producing gallery and museum exhibitions and delivering workshops and other presentations. They also describe how walking the paths of several past earth science disasters continues to inspire new chapters in their "Layers: Places in Peril" exhibit! A slide show includes images of paintings for "small problems, Big Trouble". Brey and Waller will lead a discussion on their process of incorporating broader collaboration with geoscientists and others in an educational art exhibition.

A Venom-derived Neurotoxin, CsTx-1, from the Spider Cupiennius salei Exhibits Cytolytic Activities*

PubMed Central

Kuhn-Nentwig, Lucia; Fedorova, Irina M.; Lüscher, Benjamin P.; Kopp, Lukas S.; Trachsel, Christian; Schaller, Johann; Vu, Xuan Lan; Seebeck, Thomas; Streitberger, Kathrin; Nentwig, Wolfgang; Sigel, Erwin; Magazanik, Lev G.

2012-01-01

CsTx-1, the main neurotoxic acting peptide in the venom of the spider Cupiennius salei, is composed of 74 amino acid residues, exhibits an inhibitory cysteine knot motif, and is further characterized by its highly cationic charged C terminus. Venom gland cDNA library analysis predicted a prepropeptide structure for CsTx-1 precursor. In the presence of trifluoroethanol, CsTx-1 and the long C-terminal part alone (CT1-long; Gly-45–Lys-74) exhibit an α-helical structure, as determined by CD measurements. CsTx-1 and CT1-long are insecticidal toward Drosophila flies and destroys Escherichia coli SBS 363 cells. CsTx-1 causes a stable and irreversible depolarization of insect larvae muscle cells and frog neuromuscular preparations, which seem to be receptor-independent. Furthermore, this membranolytic activity could be measured for Xenopus oocytes, in which CsTx-1 and CT1-long increase ion permeability non-specifically. These results support our assumption that the membranolytic activities of CsTx-1 are caused by its C-terminal tail, CT1-long. Together, CsTx-1 exhibits two different functions; as a neurotoxin it inhibits L-type Ca2+ channels, and as a membranolytic peptide it destroys a variety of prokaryotic and eukaryotic cell membranes. Such a dualism is discussed as an important new mechanism for the evolution of spider venomous peptides. PMID:22613721

Shelf life, physicochemical, microbiological and antioxidant properties of purple cactus pear (Opuntia ficus indica) juice after thermoultrasound treatment.

PubMed

Cruz-Cansino, Nelly Del Socorro; Ramírez-Moreno, Esther; León-Rivera, Jesús Ernesto; Delgado-Olivares, Luis; Alanís-García, Ernesto; Ariza-Ortega, José Alberto; Manríquez-Torres, José de Jesús; Jaramillo-Bustos, Diana Pamela

2015-11-01

The objective of this study was to evaluate changes in color, betalain content, browning index, viscosity, physical stability, microbiological growth, antioxidant content and antioxidant activity of purple cactus pear juice during storage after thermoultrasonication at 80% amplitude level for 15 and 25 min in comparison with pasteurized juice. Thermoultrasound treatment for 25 min increased color stability and viscosity compared to treatment for 15 min (6.83 and 6.72 MPa, respectively), but this last parameter was significantly lower (p<0.05) compared to the control and pasteurized juices (22.47 and 26.32 MPa, respectively). Experimental treatment reduced significantly (p<0.05) sediment solids in juices. Total plate counts decreased from the first day of storage exhibiting values of 1.38 and 1.43 logCFU/mL, for 15 and 25 min treatment, respectively. Compared to the control, both treatments reduced enterobacteria counts (1.54 logCFU/mL), and compared to pasteurized juice decreased pectinmethylesterase activity (3.76 and 3.82 UPE/mL), maintained high values of ascorbic acid (252.05 and 257.18 mg AA/L) and antioxidant activity (by ABTS: 124.8 and 115.6 mg VCEAC/100 mL; and DPPH: 3114.2 and 2757.1 μmol TE/L). During storage thermoultrasonicated juices had a minimum increase in pectinmethylesterase activity (from day 14), and exhibited similar total plate counts to pasteurized juice. An increase of phenolic content was observed after 14 days of storage, particularly for treatment at 80%, 25 min, and an increase in antioxidant activity (ABTS, DPPH) by the end of storage. Copyright © 2015 Elsevier B.V. All rights reserved.

Prolonged fasting increases the response of the renin-angiotensin-aldosterone system, but not vasopressin levels, in postweaned northern elephant seal pups

NASA Technical Reports Server (NTRS)

Ortiz, R. M.; Wade, C. E.; Ortiz, C. L.

2000-01-01

The 8- to 12-week postweaning fast exhibited by northern elephant seal pups (Mirounga angustirostris) occurs without any apparent deleterious effects on fluid and electrolyte homeostasis. However, during the fast the role of vasopressin (AVP) has been shown to be inconclusive and the involvement of the renin-angiotensin-aldosterone system (RAAS) has yet to be examined. To examine the effects of prolonged fasting on these osmoregulatory hormones, 15 postweaned pups were serially blood-sampled during the first 49 days of their fast. Fasting did not induce significant changes in ionic or osmotic concentrations, suggesting electrolyte homeostasis. Total proteins were reduced by day 21 of fasting and remained depressed, suggesting a lack of dehydration. Aldosterone and plasma renin activity exhibited a correlated, linear increase over the first 49 days of the fast, suggesting an active RAAS. Aldosterone exhibited a parabolic trend over the fast with a peak at day 35, suggesting a shift in the sensitivity of the kidney to aldosterone later in the fast. AVP was elevated at day 49 only, but concentrations were relatively low. RAAS was modified during the postweaning fast in pups and appears to play a significant role in the regulation of electrolyte and, most likely, water homeostasis during this period. Copyright 2000 Academic Press.

MOLECULAR OXYGEN AND THE ADSORPTION OF PHENOLS - EFFECT OF FUNCTIONAL GROUPS

EPA Science Inventory

This study reveals that the presence of molecular oxygen (oxic conditions) has a significant impact on the exhibited adsorptive capacity of granular activated carbon (GAC) for several phenolic compounds. The increase in the GAC adsorptive capacity under oxic conditions results f...

Coordinated maturational regulation of PHEX and renal phosphate transport inhibitory activity: evidence for the pathophysiological role of PHEX in X-linked hypophosphatemia.

PubMed

Nesbitt, T; Fujiwara, I; Thomas, R; Xiao, Z S; Quarles, L D; Drezner, M K

1999-12-01

The mechanism by which inactivating mutations of PHEX (phosphate-regulating gene with homologies to endopeptidases on the X chromosome) cause X-linked hypophosphatemia remains unknown. However, recent reports suggest errant PHEX activity in osteoblasts may fail to inactivate a phosphaturic factor produced by these cells. To test this possibility, we examined coordinated maturational expression of PHEX and production of phosphate transport inhibitory activity in osteoblasts from normal and hyp-mice. We assessed the inhibitory activity in conditioned medium by examining the effects on opossum kidney cell phosphate transport and osteoblast PHEX expression by reverse transcriptase-polymerase chain reaction during a 17-day maturational period. Inhibitory activity increased as a function of osteoblast maturational stage, with no activity after 3 days and persistent activity by 6 days of culture. More significantly, equal phosphate transport inhibitory activity in conditioned medium from normal and hyp-mouse osteoblasts (control 1.90 +/- 0.12, normal 1.48 +/- 0.10, hyp 1.45 +/- 0.04 nmol/mg of protein/minute) was observed at 6 days. However, by 10 days hyp-mouse osteoblasts exhibited greater inhibitory activity than controls, and by 17 days the difference in phosphate transport inhibition maximized (control 2.08 +/- 0.09, normal 1.88 +/- 0.06, hyp 1.58 +/- 0.06 nmol/mg of protein/minute). Concurrently, we observed absent PHEX expression in normal osteoblasts after 3 days, limited production at 6 days, and significant production by day 10 of culture, while hyp-mouse osteoblasts exhibited limited PHEX activity secondary to an inactivating mutation. The data suggest that the presence of inactivating PHEX mutations results in the enhanced renal phosphate transport inhibitory activity exhibited by hyp-mouse osteoblasts.

Size-mediated response to public cues of predation risk in a tropical stream fish.

PubMed

Elvidge, C K; Ramnarine, I W; Godin, J-G J; Brown, G E

2010-11-01

In order to investigate any size-dependent differences between behavioural patterns, wild-caught Hart's rivulus Rivulus hartii of varying sizes were exposed to chemical alarm cues extracted from the skin of conspecifics or heterospecific Poecilia reticulata, or a tank water control, in a series of laboratory trials. In response to conspecific alarm cues, R. hartii subjects of the range of body sizes tested exhibited consistent, size-independent antipredator behaviours that were characterized by decreased locomotory activity and foraging levels and increased refuging behaviour. Conversely, focal R. hartii demonstrated significant size-dependent trends in response to heterospecific alarm cues, with smaller individuals exhibiting antipredator responses and larger individuals shifting their behaviour to increased levels of activity consistent with a foraging, or predatory, response. These results show that the behavioural responses of individual R. hartii to publicly available chemical alarm cues from heterospecifics are mediated by the size of the receiver. © 2010 The Authors. Journal of Fish Biology © 2010 The Fisheries Society of the British Isles.

Identifying bubble collapse in a hydrothermal system using hidden Markov models

USGS Publications Warehouse

Dawson, P.B.; Benitez, M.C.; Lowenstern, J. B.; Chouet, B.A.

2012-01-01

Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ???100 m of the station, and produced ???3500-5500 events per hour with mean durations of ???0.35-0.45s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates. copyright 2012 by the American Geophysical Union.

Identifying bubble collapse in a hydrothermal system using hiddden Markov models

USGS Publications Warehouse

Dawson, Phillip B.; Benitez, M.C.; Lowenstern, Jacob B.; Chouet, Bernard A.

2012-01-01

Beginning in July 2003 and lasting through September 2003, the Norris Geyser Basin in Yellowstone National Park exhibited an unusual increase in ground temperature and hydrothermal activity. Using hidden Markov model theory, we identify over five million high-frequency (>15 Hz) seismic events observed at a temporary seismic station deployed in the basin in response to the increase in hydrothermal activity. The source of these seismic events is constrained to within ~100 m of the station, and produced ~3500–5500 events per hour with mean durations of ~0.35–0.45 s. The seismic event rate, air temperature, hydrologic temperatures, and surficial water flow of the geyser basin exhibited a marked diurnal pattern that was closely associated with solar thermal radiance. We interpret the source of the seismicity to be due to the collapse of small steam bubbles in the hydrothermal system, with the rate of collapse being controlled by surficial temperatures and daytime evaporation rates.

Carbon nanotube-lipase hybrid nanoflowers with enhanced enzyme activity and enantioselectivity.

PubMed

Li, Kai; Wang, Jianhua; He, Yaojia; Abdulrazaq, Miaad Adnan; Yan, Yunjun

2018-06-19

Various nanoflowers are synthesized as supports for different methods of enzyme immobilization; however, the activities of these immobilized enzymes are limited because of their confinement in the nanoflowers. In order to increase the performance of nanoflowers, in this study, different protein-phosphate hybrid nanostructures were successfully synthesized and further enhanced by carbon nanotubes (CNTs) under the same conditions. Only Cu 3 (PO 4 ) 2 complex nanostructures exhibited flower-like structures and showed excellent results after enhancement with CNTs in this framework. An esterification reaction between lauric acid and 1-dodecanol was used to test enzyme activity during immobilization, revealing that the Cu 3 (PO 4 ) 2 /CNT/protein complex exhibited 68-fold higher activity relative to free lipase and 51-fold higher than that of Cu 3 (PO 4 ) 2 /Burkholderia cepacia lipase hybrid nanoflowers in the absence of CNTs. All three hybrid nanostructures showed good performance and exhibited excellent reusability in resolution reactions between 1-phenylethanol and vinyl acetate. Additionally, the substrate enantiomeric excess (ee s ) reached 98% in only 10 min, and the corresponding Cu 3 (PO 4 ) 2 /CNT/protein complex could be recycled eight times without obvious loss of activity. This approach involving nanoflowers enhanced with CNTs will be highly beneficial for decreasing mass-transfer resistance and providing enhanced enzyme loading along with promising potential for industrial application. Copyright © 2018 Elsevier B.V. All rights reserved.

Novel molecular insights into RhoA GTPase-induced resistance to aqueous humor outflow through the trabecular meshwork

PubMed Central

Zhang, Min; Maddala, Rupalatha; Rao, Ponugoti Vasantha

2008-01-01

Impaired drainage of aqueous humor through the trabecular meshwork (TM) culminating in increased intraocular pressure is a major risk factor for glaucoma, a leading cause of blindness worldwide. Regulation of aqueous humor drainage through the TM, however, is poorly understood. The role of RhoA GTPase-mediated actomyosin organization, cell adhesive interactions, and gene expression in regulation of aqueous humor outflow was investigated using adenoviral vector-driven expression of constitutively active mutant of RhoA (RhoAV14). Organ-cultured anterior segments from porcine eyes expressing RhoAV14 exhibited significant reduction of aqueous humor outflow. Cultured TM cells expressing RhoAV14 exhibited a pronounced contractile morphology, increased actin stress fibers, and focal adhesions and increased levels of phosphorylated myosin light chain (MLC), collagen IV, fibronectin, and laminin. cDNA microarray analysis of RNA extracted from RhoAV14-expressing human TM cells revealed a significant increase in the expression of genes encoding extracellular matrix (ECM) proteins, cytokines, integrins, cytoskeletal proteins, and signaling proteins. Conversely, various ECM proteins stimulated robust increases in phosphorylation of MLC, paxillin, and focal adhesion kinase and activated Rho GTPase and actin stress fiber formation in TM cells, indicating a potential regulatory feedback interaction between ECM-induced mechanical strain and Rho GTPase-induced isometric tension in TM cells. Collectively, these data demonstrate that sustained activation of Rho GTPase signaling in the aqueous humor outflow pathway increases resistance to aqueous humor outflow through the trabecular pathway by influencing the actomyosin assembly, cell adhesive interactions, and the expression of ECM proteins and cytokines in TM cells. PMID:18799648

Outstanding catalytic activity of ultra-pure platinum nanoparticles.

PubMed

Januszewska, Aneta; Dercz, Grzegorz; Piwowar, Justyna; Jurczakowski, Rafal; Lewera, Adam

2013-12-09

Small (4 nm) nanoparticles with a narrow size distribution, exceptional surface purity, and increased surface order, which exhibits itself as an increased presence of basal crystallographic planes, can be obtained without the use of any surfactant. These nanoparticles can be used in many applications in an as-received state and are threefold more active towards a model catalytic reaction (oxidation of ethylene glycol). Furthermore, the superior properties of this material are interesting not only due to the increase in their intrinsic catalytic activity, but also due to the exceptional surface purity itself. The nanoparticles can be used directly (i.e., as-received, without any cleaning steps) in biomedical applications (i.e., as more efficient drug carriers due to an increased number of adsorption sites) and in energy-harvesting/data-storage devices. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sensorimotor Rhythm Neurofeedback Enhances Golf Putting Performance.

PubMed

Cheng, Ming-Yang; Huang, Chung-Ju; Chang, Yu-Kai; Koester, Dirk; Schack, Thomas; Hung, Tsung-Min

2015-12-01

Sensorimotor rhythm (SMR) activity has been related to automaticity during skilled action execution. However, few studies have bridged the causal link between SMR activity and sports performance. This study investigated the effect of SMR neurofeedback training (SMR NFT) on golf putting performance. We hypothesized that preelite golfers would exhibit enhanced putting performance after SMR NFT. Sixteen preelite golfers were recruited and randomly assigned into either an SMR or a control group. Participants were asked to perform putting while electroencephalogram (EEG) was recorded, both before and after intervention. Our results showed that the SMR group performed more accurately when putting and exhibited greater SMR power than the control group after 8 intervention sessions. This study concludes that SMR NFT is effective for increasing SMR during action preparation and for enhancing golf putting performance. Moreover, greater SMR activity might be an EEG signature of improved attention processing, which induces superior putting performance.

Arctic Forecasts Available from Polar Bear Exhibit as an Example of Formal/Informal Collaboration

NASA Astrophysics Data System (ADS)

Landis, C. E.; Cervenec, J.

2012-12-01

A subset of the general population enjoys and frequents informal education venues, offering an opportunity for lifelong learning that also enhances and supports formal education efforts. The Byrd Polar Research Center (BPRC) at The Ohio State University collaborated with the Columbus Zoo & Aquarium (CZA) in the development of their Polar Frontier exhibit, from its initial planning to the Grand Opening of the exhibit, through the present. Of course, the addition to the Zoo of polar bears and Arctic fox in the Polar Frontier has been very popular, with almost a 7% increase in visitors in 2010 when the exhibit opened. The CZA and BPRC are now investigating ways to increase the climate literacy impact of the exhibit, and to increase engagement with the topics through follow-on activities. For example, individuals or classes anywhere in the world can check forecasts from the Polar Weather and Research Forecasting model and compare them to observed conditions-- allowing deep investigation into changes in the Arctic. In addition, opportunities exist to adapt the Zoo School experience (affecting several Central Ohio school districts) and/or to enable regular participation through social media such as Facebook, Twitter, and other forms of digital communication. BPRC's sustained engagement with the CZA is an example of a trusted and meaningful partnership where open dialogue exists about providing the best learning experience for visitors. This presentation will share some of the lessons learned from this unique partnership, and strategies that are adopted to move it forward.

The Virtual Quake earthquake simulator: a simulation-based forecast of the El Mayor-Cucapah region and evidence of predictability in simulated earthquake sequences

NASA Astrophysics Data System (ADS)

Yoder, Mark R.; Schultz, Kasey W.; Heien, Eric M.; Rundle, John B.; Turcotte, Donald L.; Parker, Jay W.; Donnellan, Andrea

2015-12-01

In this manuscript, we introduce a framework for developing earthquake forecasts using Virtual Quake (VQ), the generalized successor to the perhaps better known Virtual California (VC) earthquake simulator. We discuss the basic merits and mechanics of the simulator, and we present several statistics of interest for earthquake forecasting. We also show that, though the system as a whole (in aggregate) behaves quite randomly, (simulated) earthquake sequences limited to specific fault sections exhibit measurable predictability in the form of increasing seismicity precursory to large m > 7 earthquakes. In order to quantify this, we develop an alert-based forecasting metric, and show that it exhibits significant information gain compared to random forecasts. We also discuss the long-standing question of activation versus quiescent type earthquake triggering. We show that VQ exhibits both behaviours separately for independent fault sections; some fault sections exhibit activation type triggering, while others are better characterized by quiescent type triggering. We discuss these aspects of VQ specifically with respect to faults in the Salton Basin and near the El Mayor-Cucapah region in southern California, USA and northern Baja California Norte, Mexico.

The Virtual Quake Earthquake Simulator: Earthquake Probability Statistics for the El Mayor-Cucapah Region and Evidence of Predictability in Simulated Earthquake Sequences

NASA Astrophysics Data System (ADS)

Schultz, K.; Yoder, M. R.; Heien, E. M.; Rundle, J. B.; Turcotte, D. L.; Parker, J. W.; Donnellan, A.

2015-12-01

We introduce a framework for developing earthquake forecasts using Virtual Quake (VQ), the generalized successor to the perhaps better known Virtual California (VC) earthquake simulator. We discuss the basic merits and mechanics of the simulator, and we present several statistics of interest for earthquake forecasting. We also show that, though the system as a whole (in aggregate) behaves quite randomly, (simulated) earthquake sequences limited to specific fault sections exhibit measurable predictability in the form of increasing seismicity precursory to large m > 7 earthquakes. In order to quantify this, we develop an alert based forecasting metric similar to those presented in Keilis-Borok (2002); Molchan (1997), and show that it exhibits significant information gain compared to random forecasts. We also discuss the long standing question of activation vs quiescent type earthquake triggering. We show that VQ exhibits both behaviors separately for independent fault sections; some fault sections exhibit activation type triggering, while others are better characterized by quiescent type triggering. We discuss these aspects of VQ specifically with respect to faults in the Salton Basin and near the El Mayor-Cucapah region in southern California USA and northern Baja California Norte, Mexico.

Hyperactivity and hyperconnectivity of the default network in schizophrenia and in first-degree relatives of persons with schizophrenia.

PubMed

Whitfield-Gabrieli, Susan; Thermenos, Heidi W; Milanovic, Snezana; Tsuang, Ming T; Faraone, Stephen V; McCarley, Robert W; Shenton, Martha E; Green, Alan I; Nieto-Castanon, Alfonso; LaViolette, Peter; Wojcik, Joanne; Gabrieli, John D E; Seidman, Larry J

2009-01-27

We examined the status of the neural network mediating the default mode of brain function, which typically exhibits greater activation during rest than during task, in patients in the early phase of schizophrenia and in young first-degree relatives of persons with schizophrenia. During functional MRI, patients, relatives, and controls alternated between rest and performance of working memory (WM) tasks. As expected, controls exhibited task-related suppression of activation in the default network, including medial prefrontal cortex (MPFC) and posterior cingulate cortex/precuneus. Patients and relatives exhibited significantly reduced task-related suppression in MPFC, and these reductions remained after controlling for performance. Increased task-related MPFC suppression correlated with better WM performance in patients and relatives and with less psychopathology in all 3 groups. For WM task performance, patients and relatives had greater activation in right dorsolateral prefrontal cortex (DLPFC) than controls. During rest and task, patients and relatives exhibited abnormally high functional connectivity within the default network. The magnitudes of default network connectivity during rest and task correlated with psychopathology in the patients. Further, during both rest and task, patients exhibited reduced anticorrelations between MPFC and DLPFC, a region that was hyperactivated by patients and relatives during WM performance. Among patients, the magnitude of MPFC task suppression negatively correlated with default connectivity, suggesting an association between the hyperactivation and hyperconnectivity in schizophrenia. Hyperactivation (reduced task-related suppression) of default regions and hyperconnectivity of the default network may contribute to disturbances of thought in schizophrenia and risk for the illness.

Hyperactivity and hyperconnectivity of the default network in schizophrenia and in first-degree relatives of persons with schizophrenia

PubMed Central

Whitfield-Gabrieli, Susan; Thermenos, Heidi W.; Milanovic, Snezana; Tsuang, Ming T.; Faraone, Stephen V.; McCarley, Robert W.; Shenton, Martha E.; Green, Alan I.; Nieto-Castanon, Alfonso; LaViolette, Peter; Wojcik, Joanne; Gabrieli, John D. E.; Seidman, Larry J.

2009-01-01

We examined the status of the neural network mediating the default mode of brain function, which typically exhibits greater activation during rest than during task, in patients in the early phase of schizophrenia and in young first-degree relatives of persons with schizophrenia. During functional MRI, patients, relatives, and controls alternated between rest and performance of working memory (WM) tasks. As expected, controls exhibited task-related suppression of activation in the default network, including medial prefrontal cortex (MPFC) and posterior cingulate cortex/precuneus. Patients and relatives exhibited significantly reduced task-related suppression in MPFC, and these reductions remained after controlling for performance. Increased task-related MPFC suppression correlated with better WM performance in patients and relatives and with less psychopathology in all 3 groups. For WM task performance, patients and relatives had greater activation in right dorsolateral prefrontal cortex (DLPFC) than controls. During rest and task, patients and relatives exhibited abnormally high functional connectivity within the default network. The magnitudes of default network connectivity during rest and task correlated with psychopathology in the patients. Further, during both rest and task, patients exhibited reduced anticorrelations between MPFC and DLPFC, a region that was hyperactivated by patients and relatives during WM performance. Among patients, the magnitude of MPFC task suppression negatively correlated with default connectivity, suggesting an association between the hyperactivation and hyperconnectivity in schizophrenia. Hyperactivation (reduced task-related suppression) of default regions and hyperconnectivity of the default network may contribute to disturbances of thought in schizophrenia and risk for the illness. PMID:19164577

Optimizing donor scheduling before recruitment: An effective approach to increasing apheresis platelet collections.

PubMed

Lokhandwala, Parvez M; Shike, Hiroko; Wang, Ming; Domen, Ronald E; George, Melissa R

2018-01-01

Typical approach for increasing apheresis platelet collections is to recruit new donors. Here, we investigated the effectiveness of an alternative strategy: optimizing donor scheduling, prior to recruitment, at a hospital-based blood donor center. Analysis of collections, during the 89 consecutive months since opening of donor center, was performed. Linear regression and segmented time-series analyses were performed to calculate growth rates of collections and to test for statistical differences, respectively. Pre-intervention donor scheduling capacity was 39/month. In the absence of active donor recruitment, during the first 29 months, the number of collections rose gradually to 24/month (growth-rate of 0.70/month). However, between month-30 and -55, collections exhibited a plateau at 25.6 ± 3.0 (growth-rate of -0.09/month) (p<0.0001). This plateau-phase coincided with donor schedule approaching saturation (65.6 ± 7.6% schedule booked). Scheduling capacity was increased by following two interventions: adding an apheresis instrument (month-56) and adding two more collection days/week (month-72). Consequently, the scheduling capacity increased to 130/month. Post-interventions, apheresis platelet collections between month-56 and -81 exhibited a spontaneous renewed growth at a rate of 0.62/month (p<0.0001), in absence of active donor recruitment. Active donor recruitment in month-82 and -86, when the donor schedule had been optimized to accommodate further growth, resulted in a dramatic but transient surge in collections. Apheresis platelet collections plateau at nearly 2/3rd of the scheduling capacity. Optimizing the scheduling capacity prior to active donor recruitment is an effective strategy to increase platelet collections at a hospital-based donor center.

Optimal interdependence enhances the dynamical robustness of complex systems.

PubMed

Singh, Rishu Kumar; Sinha, Sitabhra

2017-08-01

Although interdependent systems have usually been associated with increased fragility, we show that strengthening the interdependence between dynamical processes on different networks can make them more likely to survive over long times. By coupling the dynamics of networks that in isolation exhibit catastrophic collapse with extinction of nodal activity, we demonstrate system-wide persistence of activity for an optimal range of interdependence between the networks. This is related to the appearance of attractors of the global dynamics comprising disjoint sets ("islands") of stable activity.

Optimal interdependence enhances the dynamical robustness of complex systems

NASA Astrophysics Data System (ADS)

Singh, Rishu Kumar; Sinha, Sitabhra

2017-08-01

Although interdependent systems have usually been associated with increased fragility, we show that strengthening the interdependence between dynamical processes on different networks can make them more likely to survive over long times. By coupling the dynamics of networks that in isolation exhibit catastrophic collapse with extinction of nodal activity, we demonstrate system-wide persistence of activity for an optimal range of interdependence between the networks. This is related to the appearance of attractors of the global dynamics comprising disjoint sets ("islands") of stable activity.

Compassionate love buffers stress-reactive mothers from fight-or-flight parenting.

PubMed

Miller, Jonas G; Kahle, Sarah; Lopez, Monica; Hastings, Paul D

2015-01-01

The links among mothers' compassionate love for their child, autonomic nervous system activity, and parenting behavior during less and more challenging mother-child interactions were examined. Mothers expressed and reported less negative affect when they exhibited autonomic patterns of increased parasympathetic dominance (high parasympathetic and low sympathetic activation) or autonomic coactivation (high parasympathetic and high sympathetic activation) during the less challenging interaction and autonomic coactivation during the more challenging interaction. Compassionate love predicted less reported and observed negativity in mothers who showed increased sympathetic nervous system dominance (high sympathetic and low parasympathetic activation). Compassionate love appeared to help mothers, and particularly those who experienced strong physiological arousal during difficult parenting situations, establish positive socialization contexts for their children and avoid stress-induced adverse parenting.

The role of polymorphisms in the spliced leader addition domain in determining promoter activity in Brugia malayi.

PubMed

Bailey, Michelle; Chauhan, Chitra; Liu, Canhui; Unnasch, Thomas R

2011-03-01

Previous studies of Brugia malayi promoters have suggested that they are unusual in that they lack the CAAT or TATAA boxes that are often emblematic of eucaryotic core promoter domains. Instead, the region surrounding the spliced leader (SL) addition site appears to function as the core promoter domain in B. malayi. To test the hypothesis that polymorphisms in this SL addition domain are important determinants of promoter activity, a series of domain swap mutants were prepared replacing the SL addition domain of the B. malayi 13kDa large subunit ribosomal protein (BmRPL13) with those of other ribosomal protein (RP) promoters exhibiting a wide range of activities. These constructs were then tested for promoter activity in a homologous transient transfection system. On average, polymorphisms in the SL addition domain were found to be responsible for 80% of the variation in promoter activity exhibited by the RP promoters tested. Essentially all of this effect could be attributable to polymorphisms in the 10nt located directly upstream of the SL addition site. A comparison of the sequence of this domain to the promoter activity exhibited by the domain swap mutants suggested that promoter activity was related to the number of T residues present in the coding strand of the upstream domain. Confirming this, mutation of the upstream domain of the promoter of the BmRPS4 gene to a homogeneous stretch of 10 T residues resulted in a significant increase in promoter activity. Copyright © 2010 Elsevier B.V. All rights reserved.

SnRK1 is differentially regulated in the cotyledon and embryo axe of bean (Phaseolus vulgaris L) seeds.

PubMed

Coello, Patricia; Martínez-Barajas, Eleazar

2014-07-01

SnRK1 activity is developmentally regulated in bean seeds and exhibits a transient increase with the highest value at 20 days after anthesis (DAA), which coincides with the beginning of protein and starch accumulation. The catalytic subunit of SnRK1 shows a consistent decrease throughout the seed development period. However, by 15 DAA a significant proportion of the catalytic subunit appears phosphorylated. The increase in activity and phosphorylation of the catalytic subunit coincides with a decrease in hexoses. However, SnRK1 activity is differentially regulated in the cotyledon and embryo axe, where a larger proportion of the catalytic subunit is phosphorylated. SnRK1 obtained from endosperm extract is inhibited by T6P and to a lesser extent by ADPG and UDPG, whereas the enzyme isolated from embryo is virtually insensitive to T6P but exhibits some inhibition by ADPG and UDPG. In cotyledon extracts, the effects of T6P and ADPG on SnRK1 activity are additive, whereas in embryo extract, T6P inhibits the enzyme only when ADPG is present. After fractionation on Sephacryl-S300, SnRK1 activity obtained from cotyledon extracts is detected as a single peak associated with a molecular weight of 250 kDa whereas that obtained form embryo axe extracts detected as 2 peaks associated with molecular weight of 250 and 180 kDa. In both cases, the catalytic subunit exhibits a wide distribution but is concentrated in the fractions with the highest activity. To analyse the composition of the complex, cotyledon and embryo extracts were treated with a reversible crosslinker (DSP). DSP induced the formation of complexes with molecular weights of 97 and 180 kDa in the cotyledon and embryo extracts, respectively. Since all the phosphorylated catalytic subunit is present in the complexes induced by DSP, it appears that the phosphorylation favors its interaction with other proteins. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

The Grass Might Be Greener: Medical Marijuana Patients Exhibit Altered Brain Activity and Improved Executive Function after 3 Months of Treatment

PubMed Central

Gruber, Staci A.; Sagar, Kelly A.; Dahlgren, Mary K.; Gonenc, Atilla; Smith, Rosemary T.; Lambros, Ashley M.; Cabrera, Korine B.; Lukas, Scott E.

2018-01-01

The vast majority of states have enacted full or partial medical marijuana (MMJ) programs, causing the number of patients seeking certification for MMJ use to increase dramatically in recent years. Despite increased use of MMJ across the nation, no studies thus far have examined the specific impact of MMJ on cognitive function and related brain activation. In the present study, MMJ patients seeking treatment for a variety of documented medical conditions were assessed prior to initiating MMJ treatment and after 3 months of treatment as part of a larger longitudinal study. In order to examine the effect of MMJ treatment on task-related brain activation, MMJ patients completed the Multi-Source Interference Test (MSIT) while undergoing functional magnetic resonance imaging (fMRI). We also collected data regarding conventional medication use, clinical state, and health-related measures at each visit. Following 3 months of treatment, MMJ patients demonstrated improved task performance accompanied by changes in brain activation patterns within the cingulate cortex and frontal regions. Interestingly, after MMJ treatment, brain activation patterns appeared more similar to those exhibited by healthy controls from previous studies than at pre-treatment, suggestive of a potential normalization of brain function relative to baseline. These findings suggest that MMJ use may result in different effects relative to recreational marijuana (MJ) use, as recreational consumers have been shown to exhibit decrements in task performance accompanied by altered brain activation. Moreover, patients in the current study also reported improvements in clinical state and health-related measures as well as notable decreases in prescription medication use, particularly opioids and benzodiapezines after 3 months of treatment. Further research is needed to clarify the specific neurobiologic impact, clinical efficacy, and unique effects of MMJ for a range of indications and how it compares to recreational MJ use. PMID:29387010

The Grass Might Be Greener: Medical Marijuana Patients Exhibit Altered Brain Activity and Improved Executive Function after 3 Months of Treatment.

PubMed

Gruber, Staci A; Sagar, Kelly A; Dahlgren, Mary K; Gonenc, Atilla; Smith, Rosemary T; Lambros, Ashley M; Cabrera, Korine B; Lukas, Scott E

2017-01-01

The vast majority of states have enacted full or partial medical marijuana (MMJ) programs, causing the number of patients seeking certification for MMJ use to increase dramatically in recent years. Despite increased use of MMJ across the nation, no studies thus far have examined the specific impact of MMJ on cognitive function and related brain activation. In the present study, MMJ patients seeking treatment for a variety of documented medical conditions were assessed prior to initiating MMJ treatment and after 3 months of treatment as part of a larger longitudinal study. In order to examine the effect of MMJ treatment on task-related brain activation, MMJ patients completed the Multi-Source Interference Test (MSIT) while undergoing functional magnetic resonance imaging (fMRI). We also collected data regarding conventional medication use, clinical state, and health-related measures at each visit. Following 3 months of treatment, MMJ patients demonstrated improved task performance accompanied by changes in brain activation patterns within the cingulate cortex and frontal regions. Interestingly, after MMJ treatment, brain activation patterns appeared more similar to those exhibited by healthy controls from previous studies than at pre-treatment, suggestive of a potential normalization of brain function relative to baseline. These findings suggest that MMJ use may result in different effects relative to recreational marijuana (MJ) use, as recreational consumers have been shown to exhibit decrements in task performance accompanied by altered brain activation. Moreover, patients in the current study also reported improvements in clinical state and health-related measures as well as notable decreases in prescription medication use, particularly opioids and benzodiapezines after 3 months of treatment. Further research is needed to clarify the specific neurobiologic impact, clinical efficacy, and unique effects of MMJ for a range of indications and how it compares to recreational MJ use.

Repeating firing fields of CA1 neurons shift forward in response to increasing angular velocity.

PubMed

Cowen, Stephen L; Nitz, Douglas A

2014-01-01

Self-motion information influences spatially-specific firing patterns exhibited by hippocampal neurons. Moreover, these firing patterns can repeat across similar subsegments of an environment, provided that there is similarity of path shape and head orientations across subsegments. The influence of self-motion variables on repeating fields remains to be determined. To investigate the role of path shape and angular rotation on hippocampal activity, we recorded the activity of CA1 neurons from rats trained to run on spiral-shaped tracks. During inbound traversals of circular-spiral tracks, angular velocity increases continuously. Under this condition, most neurons (74%) exhibited repeating fields across at least three adjacent loops. Of these neurons, 86% exhibited forward shifts in the angles of field centers relative to centers on preceding loops. Shifts were absent on squared-spiral tracks, minimal and less reliable on concentric-circle tracks, and absent on outward-bound runs on circular-spiral tracks. However, outward-bound runs on the circular-spiral track in the dark were associated with backward shifts. Together, the most parsimonious interpretation of the results is that continuous increases or decreases in angular velocity are particularly effective at shifting the center of mass of repeating fields, although it is also possible that a nonlinear integration of step counts contributes to the shift. Furthermore, the unexpected absence of field shifts during outward journeys in light (but not darkness) suggests visual cues around the goal location anchored the map of space to an allocentric reference frame.

Respiration and substrate transport rates as well as reactive oxygen species production distinguish mitochondria from brain and liver.

PubMed

Gusdon, Aaron M; Fernandez-Bueno, Gabriel A; Wohlgemuth, Stephanie; Fernandez, Jenelle; Chen, Jing; Mathews, Clayton E

2015-09-10

Aberrant mitochondrial function, including excessive reactive oxygen species (ROS) production, has been implicated in the pathogenesis of human diseases. The use of mitochondrial inhibitors to ascertain the sites in the electron transport chain (ETC) resulting in altered ROS production can be an important tool. However, the response of mouse mitochondria to ETC inhibitors has not been thoroughly assessed. Here we set out to characterize the differences in phenotypic response to ETC inhibitors between the more energetically demanding brain mitochondria and less energetically demanding liver mitochondria in commonly utilized C57BL/6J mice. We show that in contrast to brain mitochondria, inhibiting distally within complex I or within complex III does not increase liver mitochondrial ROS production supported by complex I substrates, and liver mitochondrial ROS production supported by complex II substrates occurred primarily independent of membrane potential. Complex I, II, and III enzymatic activities and membrane potential were equivalent between liver and brain and responded to ETC. inhibitors similarly. Brain mitochondria exhibited an approximately two-fold increase in complex I and II supported respiration compared with liver mitochondria while exhibiting similar responses to inhibitors. Elevated NADH transport and heightened complex II-III coupled activity accounted for increased complex I and II supported respiration, respectively in brain mitochondria. We conclude that important mechanistic differences exist between mouse liver and brain mitochondria and that mouse mitochondria exhibit phenotypic differences compared with mitochondria from other species.

Oxaliplatin Analogues with Carboxy Derivatives of Boldine with Enhanced Antioxidant Activity

PubMed Central

Mellado, Marco; Jara, Carlos; Astudillo, David; Villena, Joan; Reveco, Patricio G.; Thomet, Franz A.

2015-01-01

A new oxaliplatin analog [Pt(dach)(L5)] (1) was synthesized and characterized as a continuation of a study of the previously reported [Pt(dach)(L6)] (2), where dach = (1R,2R)-diaminocyclohexane, L5 = 3-carboxyboldine, and L6 = 3-carboxypredicentrine. Compounds 1 and 2 exhibited a substantially enhanced antioxidant activity compared to oxaliplatin (130 and 30 times for 1 and 13 and 4 times for 2 using the DPPH and FRAP assays, resp.). In addition, 1 and 2 exhibited cytotoxic activity in the same range as oxaliplatin toward the two human tumor cell lines (MCF-7 and HT-29) studied and two to four times lower activity in the human colon nontumor cell line (CCD-841). Preadministration of L5 or L6 to the colon tumor (HT-29) and the colon nontumor (CCD-841) cell lines prior to oxaliplatin addition increased the viability of the nontumor cell line to a greater extent than that of the tumor cell line. PMID:25814916

Silver Nanoparticles Synthesized Using Caesalpinia sappan Extract as Potential Novel Nanoantibiotics Against Methicillin-Resistant Staphylococcus aureus.

PubMed

Jun, Sang Hui; Cha, Song-Hyun; Kim, Jae-Hyun; Yoon, Minho; Cho, Seonho; Park, Youmie

2015-08-01

Silver nanoparticles (AgNPs) have been shown to be effective antibacterial agents against methicillin-resistant Staphylococcus aureus (MRSA). In this study, AgNPs were synthesized using Caesalpinia sappan extract as a reducing agent to convert Ag+ to AgNPs. Seven stabilizers (surfactants and polymers) were added during the reduction step to increase the colloidal stability and to enhance the antibacterial activity of the AgNPs. Spherical and amorphous particles were primarily observed, with estimated diameters ranging from 30.2 to 47.5 nm. X-ray diffraction confirmed the face centered cubic structures of the AgNPs. Among the employed stabilizers, the cationic surfactant cetyltrimethylammonium bromide (CTAB) exhibited the highest antibacterial activity against 19 strains of MRSA, followed by polyvinylpyrrolidone (PVP, average molecular weight of 10,000). In contrast, the anionic surfactants sodium dodecyl sulfate (SDS) and sodium dodecylbenzene sulfonate (NaDDBS) did not exhibit any significant antibacterial activity, suggesting that the cationic surfactant head group contributed to the higher antibacterial activity of the AgNPs against MRSA.

Piezo1 links mechanical forces to red blood cell volume.

PubMed

Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

2015-05-22

Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis.

Chitosan derivatives targeting lipid bilayers: Synthesis, biological activity and interaction with model membranes.

PubMed

Martins, Danubia Batista; Nasário, Fábio Domingues; Silva-Gonçalves, Laiz Costa; de Oliveira Tiera, Vera Aparecida; Arcisio-Miranda, Manoel; Tiera, Marcio José; Dos Santos Cabrera, Marcia Perez

2018-02-01

The antimicrobial activity of chitosan and derivatives to human and plant pathogens represents a high-valued prospective market. Presently, two low molecular weight derivatives, endowed with hydrophobic and cationic character at different ratios were synthesized and characterized. They exhibit antimicrobial activity and increased performance in relation to the intermediate and starting compounds. However, just the derivative with higher cationic character showed cytotoxicity towards human cervical carcinoma cells. Considering cell membranes as targets, the mode of action was investigated through the interaction with model lipid vesicles mimicking bacterial, tumoral and erythrocyte membranes. Intense lytic activity and binding are demonstrated for both derivatives in anionic bilayers. The less charged compound exhibits slightly improved selectivity towards bacterial model membranes, suggesting that balancing its hydrophobic/hydrophilic character may improve efficiency. Observing the aggregation of vesicles, we hypothesize that the "charge cluster mechanism", ascribed to some antimicrobial peptides, could be applied to these chitosan derivatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

Chromosome territory repositioning induced by PHA-activation of lymphocytes: A 2D and 3D appraisal.

PubMed

Ioannou, Dimitrios; Kandukuri, Lakshmi; Simpson, Joe Leigh; Tempest, Helen Ghislaine

2015-01-01

Genomes and by extension chromosome territories (CTs) in a variety of organisms exhibit nonrandom organization within interphase nuclei. CTs are susceptible to movement upon induction by a variety of stimuli, including: cell differentiation, growth factors, genotoxic agents, proliferating status, and stimulants that induce novel transcription profiles. These findings suggest nuclear architecture can undergo reorganization, providing support for a functional significance of CT organization. The effect of the initiation of transcription on global scale chromatin architecture has been underexplored. This study investigates the organization of all 24 human chromosomes in lymphocytes from two individuals in resting and phytohaemagglutinin activated lymphocytes using 2D and 3D approaches. The radial organization of CTs in lymphocytes in both resting and activated lymphocytes follows a gene-density pattern. However, CT organization in activated nuclei appears less constrained exhibiting a more random organization. We report differences in the spatial relationship between homologous and heterologous CTs in activated nuclei. In addition, a reproducible radial hierarchy of CTs was identified and evidence of a CT repositioning was observed in activated nuclei using both 2D and 3D approaches. Alterations between resting and activated lymphocytes could be adaptation of CTs to the new transcription profile and possibly the formation of new neighborhoods of interest or interaction of CTs with nuclear landmarks. The increased distances between homologous and heterologous CTs in activated lymphocytes could be a reflection of a defensive mechanism to reduce potential interaction to prevent any structural chromosome abnormalities (e.g. translocations) as a result of DNA damage that increases during lymphocyte activation.

Adjustments differ among low-threshold motor units during intermittent, isometric contractions.

PubMed

Farina, Dario; Holobar, Ales; Gazzoni, Marco; Zazula, Damjan; Merletti, Roberto; Enoka, Roger M

2009-01-01

We investigated the changes in muscle fiber conduction velocity, recruitment and derecruitment thresholds, and discharge rate of low-threshold motor units during a series of ramp contractions. The aim was to compare the adjustments in motor unit activity relative to the duration that each motor unit was active during the task. Multichannel surface electromyographic (EMG) signals were recorded from the abductor pollicis brevis muscle of eight healthy men during 12-s contractions (n = 25) in which the force increased and decreased linearly from 0 to 10% of the maximum. The maximal force exhibited a modest decline (8.5 +/- 9.3%; P < 0.05) at the end of the task. The discharge times of 73 motor units that were active for 16-98% of the time during the first five contractions were identified throughout the task by decomposition of the EMG signals. Action potential conduction velocity decreased during the task by a greater amount for motor units that were initially active for >70% of the time compared with that of less active motor units. Moreover, recruitment and derecruitment thresholds increased for these most active motor units, whereas the thresholds decreased for the less active motor units. Another 18 motor units were recruited at an average of 171 +/- 32 s after the beginning of the task. The recruitment and derecruitment thresholds of these units decreased during the task, but muscle fiber conduction velocity did not change. These results indicate that low-threshold motor units exhibit individual adjustments in muscle fiber conduction velocity and motor neuron activation that depended on the relative duration of activity during intermittent contractions.

Hyperphagia, lower body temperature, and reduced running wheel activity precede development of morbid obesity in New Zealand obese mice.

PubMed

Jürgens, Hella S; Schürmann, Annette; Kluge, Reinhart; Ortmann, Sylvia; Klaus, Susanne; Joost, Hans-Georg; Tschöp, Matthias H

2006-04-13

Among polygenic mouse models of obesity, the New Zealand obese (NZO) mouse exhibits the most severe phenotype, with fat depots exceeding 40% of total body weight at the age of 6 mo. Here we dissected the components of energy balance including feeding behavior, locomotor activity, energy expenditure, and thermogenesis compared with the related lean New Zealand black (NZB) and obese B6.V-Lep(ob)/J (ob/ob) strains (11% and 65% fat at 23 wk, respectively). NZO mice exhibited a significant hyperphagia that, when food intake was expressed per metabolic body mass, was less pronounced than that of the ob/ob strain. Compared with NZB, NZO mice exhibited increased meal frequency, meal duration, and meal size. Body temperature as determined by telemetry with implanted sensors was reduced in NZO mice, but again to a lesser extent than in the ob/ob strain. In striking contrast to ob/ob mice, NZO mice were able to maintain a constant body temperature during a 20-h cold exposure, thus exhibiting a functioning cold-induced thermogenesis. No significant differences in spontaneous home cage activity were observed among NZO, NZB, and ob/ob strains. When mice had access to voluntary running wheels, however, running activity was significantly lower in NZO than NZB mice and even lower in ob/ob mice. These data indicate that obesity in NZO mice, just as in humans, is due to a combination of hyperphagia, reduced energy expenditure, and insufficient physical activity. Because NZO mice differ strikingly from the ob/ob strain in their resistance to cold stress, we suggest that the molecular defects causing hyperphagia in NZO mice are located distal from leptin and its receptor.

Effects of severity of gross motor disability on anticipatory postural adjustments while standing in individuals with bilateral spastic cerebral palsy.

PubMed

Tomita, Hidehito; Fukaya, Yoshiki; Takagi, Yukina; Yokozawa, Asami

2016-10-01

Although individuals with bilateral spastic cerebral palsy (BSCP) exhibit several deficits in anticipatory postural adjustments (APAs) while standing, effects of severity of motor disability on their APAs are unclear. To determine whether individuals with BSCP exhibit severity-dependent deficits in APAs. Seven individuals with level II BSCP (BSCP-II group) and seven with level III BSCP (BSCP-III group) according to the Gross Motor Function Classification System and seven healthy controls lifted a load under two different load conditions. Anticipatory activities of the erector spinae (ES), medial hamstring (MH), and gastrocnemius (GCM) were smaller in the two BSCP groups than in the control group. Although the anticipatory GCM activity was similar between the BSCP groups, the ES and MH activities were larger in the BSCP-II group than in the BSCP-III group. In the BSCP-II group, an increase in anticipatory activity with an increase in load was observed in the MH, but not in the GCM. In the BSCP-III group, load-related modulation was not found in the MH or GCM. The present findings suggest that in individuals with BSCP with severe motor disability, APA deficits extend to more proximal parts of the body. Copyright © 2016 Elsevier Ltd. All rights reserved.

Combined effects of lead and acid rain on photosynthesis in soybean seedlings.

PubMed

Hu, Huiqing; Wang, Lihong; Liao, Chenyu; Fan, Caixia; Zhou, Qing; Huang, Xiaohua

2014-10-01

To explore how lead (Pb) and acid rain simultaneously affect plants, the combined effects of Pb and acid rain on the chlorophyll content, chlorophyll fluorescence reaction, Hill reaction rate, and Mg(2+)-ATPase activity in soybean seedlings were investigated. The results indicated that, when soybean seedlings were treated with Pb or acid rain alone, the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, and maximal photochemical efficiency (F(v)/F(m)) were decreased, while the initial fluorescence (F 0) and maximum quantum yield (Y) were increased, compared with those of the control. The combined treatment with Pb and acid rain decreased the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, F(v)/F(m), and Y and increased F 0 in soybean seedlings. Under the combined treatment with Pb and acid rain, the two factors showed additive effects on the chlorophyll content in soybean seedlings and exhibited antagonistic effects on the Hill reaction rate. Under the combined treatment with high-concentration Pb and acid rain, the two factors exhibited synergistic effects on the Mg(2+)-ATPase activity, F 0, F v/F m, as well as Y. In summary, the inhibition of the photosynthetic process is an important physiological basis for the simultaneous actions of Pb and acid rain in soybean seedlings.

Reversal of Myoblast Aging by Tocotrienol Rich Fraction Posttreatment

PubMed Central

Wan Ngah, Wan Zurinah; Mouly, Vincent; Abdul Karim, Norwahidah

2013-01-01

Skeletal muscle satellite cells are heavily involved in the regeneration of skeletal muscle in response to the aging-related deterioration of the skeletal muscle mass, strength, and regenerative capacity, termed as sarcopenia. This study focused on the effect of tocotrienol rich fraction (TRF) on regenerative capacity of myoblasts in stress-induced premature senescence (SIPS). The myoblasts was grouped as young control, SIPS-induced, TRF control, TRF pretreatment, and TRF posttreatment. Optimum dose of TRF, morphological observation, activity of senescence-associated β-galactosidase (SA-β-galactosidase), and cell proliferation were determined. 50 μg/mL TRF treatment exhibited the highest cell proliferation capacity. SIPS-induced myoblasts exhibit large flattened cells and prominent intermediate filaments (senescent-like morphology). The activity of SA-β-galactosidase was significantly increased, but the proliferation capacity was significantly reduced as compared to young control. The activity of SA-β-galactosidase was significantly reduced and cell proliferation was significantly increased in the posttreatment group whereas there was no significant difference in SA-β-galactosidase activity and proliferation capacity of pretreatment group as compared to SIPS-induced myoblasts. Based on the data, we hypothesized that TRF may reverse the myoblasts aging through replenishing the regenerative capacity of the cells. However, further investigation on the mechanism of TRF in reversing the myoblast aging is needed. PMID:24349615

Rhizobacterium-mediated growth promotion and expression of stress enzymes in Glycine max L. Merrill against Fusarium wilt upon challenge inoculation.

PubMed

Jain, Shekhar; Vaishnav, Anukool; Kasotia, Amrita; Kumari, Sarita; Gaur, Rajarshi Kumar; Choudhary, Devendra Kumar

2014-02-01

Wilt disease of soybean caused by a very common soil-borne fungus, Fusarium oxysporum is one of the most destructive diseases of the crop. The aim of the present study was to characterize plant growth-promotion activities and induced resistance of a rhizobacterial strain for the soybean plant against F. oxysporum. Rhizobacterium strain SJ-5 exhibited plant growth-promotion characteristics and antagonistic activity against the test pathogen on dual plate assay. It was identified as a Carnobacterium sp. A 950 bp PCR product was amplified from Carnobacterium sp. strain SJ-5, using zwittermicin A self-resistance gene-specific primers (zmaR). The strain produced indole 3-acetic acid (19 μg/ml) in the presence of salt stress and exhibited growth in Dworkin and Foster salt medium amended with 1-aminocyclopropane-1-carboxylate (ACC) through ACC deaminase activity (277 nmol/mg/h) as compared to the control. Strain seeds treated with the strain significantly enhanced the quorum of healthy plants after challenge inoculation at 14 days after seeding. An increase in the activity of stress enzymes after challenge inoculation with the test pathogen is reported. Treatment with the bacterium resulted in an increase in the chlorophyll content in the leaves in comparison with challenge-inoculated plants.

Antioxidant and hypoglycemic effects of Diospyros lotus fruit fermented with Microbacterium flavum and Lactobacillus plantarum.

PubMed

Zhang, Zhi-Peng; Ma, Jun; He, Yuan-Yuan; Lu, Jun; Ren, Di-Feng

2018-06-01

Diospyros lotus, a member of the Ebenaceae family, has long been used as a traditional sedative in China. In this study, the antioxidant and hypoglycemic effects of non-fermented and microorganism-fermented D. lotus were explored. The total phenolic and vitamin C contents of microorganism-fermented D. lotus for 24-72 h were less than those of non-fermented. High-performance liquid chromatography showed that the tannic, catechinic, and ellagic acid contents increased significantly upon fermentation for 24 h. D. lotus fermented with Microbacterium flavum for 24 h exhibited the highest DPPH radical scavenging activity (IC 50  = 4.18 μg mL -1 ), and the highest ABTS radical scavenging activity was exhibited at 72 h of fermentation (IC 50  = 29.18 μg mL -1 ). The anti-α-glucosidase activity of fermented D. lotus was higher (2.06-4.73-fold) than that of non-fermented one. Thus, fermented D. lotus is a useful source of natural antioxidants, and a valuable food, exhibiting antioxidant and hypoglycemic properties. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Piezoelectric Active Humidity Sensors Based on Lead-Free NaNbO₃ Piezoelectric Nanofibers.

PubMed

Gu, Li; Zhou, Di; Cao, Jun Cheng

2016-06-07

The development of micro-/nano-scaled energy harvesters and the self-powered sensor system has attracted great attention due to the miniaturization and integration of the micro-device. In this work, lead-free NaNbO₃ piezoelectric nanofibers with a monoclinic perovskite structure were synthesized by the far-field electrospinning method. The flexible active humidity sensors were fabricated by transferring the nanofibers from silicon to a soft polymer substrate. The sensors exhibited outstanding piezoelectric energy-harvesting performance with output voltage up to 2 V during the vibration process. The output voltage generated by the NaNbO₃ sensors exhibited a negative correlation with the environmental humidity varying from 5% to 80%, where the peak-to-peak value of the output voltage generated by the sensors decreased from 0.40 to 0.07 V. The sensor also exhibited a short response time, good selectively against ethanol steam, and great temperature stability. The piezoelectric active humidity sensing property could be attributed to the increased leakage current in the NaNbO₃ nanofibers, which was generated due to proton hopping among the H₃O⁺ groups in the absorbed H₂O layers under the driving force of the piezoelectric potential.

Activity and Safety of Synthetic Lectins Based on Benzoboroxole-Functionalized Polymers for Inhibition of HIV Entry

PubMed Central

Mahalingam, Alamelu; Geonnotti, Anthony R.; Balzarini, Jan; Kiser, Patrick F.

2011-01-01

Lectins derived from plant and microbial sources constitute a vital class of entry inhibitors that target the oligomannose residues on the HIV envelope gp120. Despite their potency and specificity, success of lectin-based entry inhibitors may be impeded by issues in regards to economical production, formulation and potential mitogenicity. Therefore, there exists a gap in the HIV therapeutics pipeline that underscores the need for mass producible, synthetic, broad-spectrum, and biocomptabile inhibitors of HIV entry. Here, we present the development of a polymeric synthetic lectin, based on benzoboroxole (BzB), which exhibits weak affinity (~25 M−1) for non-reducing sugars, similar to those found on the HIV envelope. High molecular weight BzB-functionalized polymers demonstrated antiviral activity that increased with an increase in ligand density and molecular weight of the polymer construct; revealing that polyvalency improves activity. Polymers showed significant increase in activity from 25 to 75 mol% BzB functionalization with EC50 of 15 μM and 15 nM, respectively. A further increase in mole functionalization to 90% resulted in an increase of the EC50 (59 ± 5 nM), likely due to the elongated rigid structure of the polymer chain compelled by electrostatic repulsion between the boronic acid groups. An increase in molecular weight of the polymer at 50 mol% BzB functionalization showed a gradual but significant increase in antiviral activity, with the highest activity seen with the 382 kDa polymer (EC50 of 1.1 ± 0.5 nM in CEM cells and 11 ± 3 nM in TZM-bl cells). Supplementing the polymer backbone with 10 mol% sulfonic acid not only increased the aqueous solubility of the polymers by at least 50-fold, but also demonstrated a synergistic increase in anti-HIV activity (4.0 ± 1.5 nM in TZM-bl cells), possibly due to electrostatic interactions between the negatively charged polymer backbone and the positively charged V3-loop in the gp120. The benzoboroxole-sulfonic acid copolymers showed no decrease in activity in the presence of a seminal concentration of fructose (p > 0.05). Additionally, the co-polymers exhibit minimal, if any effect on the cellular viability, barrier properties, or cytokine levels in human reconstructed ecto-cervical tissue after 3 days of repeated exposure and did not show pronounced activity against a variety of other RNA and DNA viruses. PMID:21879735

Stalk-dependent and Stalk-independent Signaling by the Adhesion G Protein-coupled Receptors GPR56 (ADGRG1) and BAI1 (ADGRB1).

PubMed

Kishore, Ayush; Purcell, Ryan H; Nassiri-Toosi, Zahra; Hall, Randy A

2016-02-12

The adhesion G protein-coupled receptors (aGPCRs) are a large yet poorly understood family of seven-transmembrane proteins. A defining characteristic of the aGPCR family is the conserved GAIN domain, which has autoproteolytic activity and can cleave the receptors near the first transmembrane domain. Several aGPCRs, including ADGRB1 (BAI1 or B1) and ADGRG1 (GPR56 or G1), have been found to exhibit significantly increased constitutive activity when truncated to mimic GAIN domain cleavage (ΔNT). Recent reports have suggested that the new N-terminal stalk, which is revealed by GAIN domain cleavage, can directly activate aGPCRs as a tethered agonist. We tested this hypothesis in studies on two distinct aGPCRs, B1 and G1, by engineering mutant receptors lacking the entire NT including the stalk (B1- and G1-SL, with "SL" indicating "stalkless"). These receptors were evaluated in a battery of signaling assays and compared with full-length wild-type and cleavage-mimicking (ΔNT) forms of the two receptors. We found that B1-SL, in multiple assays, exhibited robust signaling activity, suggesting that the membrane-proximal stalk region is not necessary for its activation. For G1, however, the results were mixed, with the SL mutant exhibiting robust activity in several signaling assays (including TGFα shedding, activation of NFAT luciferase, and β-arrestin recruitment) but reduced activity relative to ΔNT in a distinct assay (activation of SRF luciferase). These data support a model in which the activation of certain pathways downstream of aGPCRs is stalk-dependent, whereas signaling to other pathways is stalk-independent. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Social support and youth physical activity: the role of provider and type.

PubMed

Beets, Michael W; Vogel, Randy; Forlaw, Loretta; Pitetti, Kenneth H; Cardinal, Bradley J

2006-01-01

To examine provider and type variation in social support (SS) for activity. Three hundred sixty-three fifth to eighth-grade students completed a questionnaire assessing self-reported activity and social support (SS) from 3 providers: mom, dad, and peers. Important covariates of activity were included in the analysis: age, BMI, sex, and maturation. Structural equation modeling indicated peers, transportation, and praise affected activity levels. Boys reported greater SS than girls did. Maturation, age, and BMI exhibited unique affects on SS. Increasing positive feedback, transportation to places to be active, and peer support may prove advantageous in improving activity levels in this age-group.

Differential transcriptional regulation by alternatively designed mechanisms: A mathematical modeling approach.

PubMed

Yildirim, Necmettin; Aktas, Mehmet Emin; Ozcan, Seyma Nur; Akbas, Esra; Ay, Ahmet

2017-01-01

Cells maintain cellular homeostasis employing different regulatory mechanisms to respond external stimuli. We study two groups of signal-dependent transcriptional regulatory mechanisms. In the first group, we assume that repressor and activator proteins compete for binding to the same regulatory site on DNA (competitive mechanisms). In the second group, they can bind to different regulatory regions in a noncompetitive fashion (noncompetitive mechanisms). For both competitive and noncompetitive mechanisms, we studied the gene expression dynamics by increasing the repressor or decreasing the activator abundance (inhibition mechanisms), or by decreasing the repressor or increasing the activator abundance (activation mechanisms). We employed delay differential equation models. Our simulation results show that the competitive and noncompetitive inhibition mechanisms exhibit comparable repression effectiveness. However, response time is fastest in the noncompetitive inhibition mechanism due to increased repressor abundance, and slowest in the competitive inhibition mechanism by increased repressor level. The competitive and noncompetitive inhibition mechanisms through decreased activator abundance show comparable and moderate response times, while the competitive and noncompetitive activation mechanisms by increased activator protein level display more effective and faster response. Our study exemplifies the importance of mathematical modeling and computer simulation in the analysis of gene expression dynamics.

Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer

PubMed Central

Harlow, Henry J.; Durner, George M.; Regehr, Eric V.; Rourke, Bryan C.; Robles, Manuel; Amstrup, Steven C.; Ben-David, Merav

2017-01-01

Abstract When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April–May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these ‘shore’ bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These ‘ice’ bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt. PMID:28835844

Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer

USGS Publications Warehouse

Whiteman, John P.; Harlow, Henry J.; Durner, George M.; Regehr, Eric V.; Rourke, Bryan C.; Robles, Manuel; Amstrup, Steven C.; Ben-David, Merav

2017-01-01

When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April–May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these ‘shore’ bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These ‘ice’ bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt.

Polar bears experience skeletal muscle atrophy in response to food deprivation and reduced activity in winter and summer.

PubMed

Whiteman, John P; Harlow, Henry J; Durner, George M; Regehr, Eric V; Rourke, Bryan C; Robles, Manuel; Amstrup, Steven C; Ben-David, Merav

2017-01-01

When reducing activity and using stored energy during seasonal food shortages, animals risk degradation of skeletal muscles, although some species avoid or minimize the resulting atrophy while experiencing these conditions during hibernation. Polar bears may be food deprived and relatively inactive during winter (when pregnant females hibernate and hunting success declines for other demographic groups) as well as summer (when sea ice retreats from key foraging habitats). We investigated muscle atrophy in samples of biceps femoris collected from free-ranging polar bears in the Southern Beaufort Sea (SBS) throughout their annual cycle. Atrophy was most pronounced in April-May as a result of food deprivation during the previous winter, with muscles exhibiting reduced protein concentration, increased water content, and lower creatine kinase mRNA. These animals increased feeding and activity in spring (when seal prey becomes more available), initiating a period of muscle recovery. During the following ice melt of late summer, ~30% of SBS bears abandon retreating sea ice for land; in August, these 'shore' bears exhibited no muscle atrophy, indicating that they had fully recovered from winter food deprivation. These individuals subsequently scavenged whale carcasses deposited by humans and by October, had retained good muscle condition. In contrast, ~70% of SBS bears follow the ice north in late summer, into deep water with less prey. These 'ice' bears fast; by October, they exhibited muscle protein loss and rapid changes in myosin heavy-chain isoforms in response to reduced activity. These findings indicate that, unlike other bears during winter hibernation, polar bears without food in summer cannot mitigate atrophy. Consequently, prolonged summer fasting resulting from climate change-induced ice loss creates a risk of greater muscle atrophy and reduced abilities to travel and hunt.

Characterization of plant growth-promoting traits of free-living diazotrophic bacteria and their inoculation effects on growth and nitrogen uptake of crop plants.

PubMed

Islam, Md Rashedul; Madhaiyan, M; Deka Boruah, Hari P; Yim, Woojong; Lee, Gillseung; Saravanan, V S; Fu, Qingling; Hu, Hongqing; Sa, Tongmin

2009-10-01

The search for diverse plant growth-promoting (PGP) diazotrophic bacteria is gaining momentum as efforts are made to exploit them as biofertilizers for various economically important crops. In the present study, 17 diazotrophic strains belonging to eight different genera isolated from rice paddy fields were screened for multiple PGP traits and evaluated for their inoculation effects on canola and rice plants. All of the strains tested positive for 1- aminocyclopropane-1-carboxylate (ACC) deaminase activity and production of indole 3-acetic acid (IAA) and ammonia (NH3). Additionally, four of the strains were able to solubilize phosphorus (P), five tested positive for zinc (Zn) solubilization and sulfur (S) oxidation, and eight strains produced siderophores. Based on the presence of multiple PGP traits, 10 strains were selected for inoculation studies. Treatment with Herbaspirillum sp. RFNB26 resulted in maximum root length (54.3%), seedling vigor, and dry biomass in canola, whereas Paenibacillus sp. RFNB4 exhibited the lowest activity under gnotobiotic conditions. However, under pot culture conditions, Paenibacillus sp. RFNB4 significantly increased plant height and dry biomass production by 42.3% and 29.5%, respectively. Canola plants and rhizosphere soils inoculated with Bacillus sp. RFNB6 exhibited significantly higher nitrogenase activity. In greenhouse experiments, Serratia sp. RFNB18 increased rice plant height by 35.1%, Xanthomonas sp. RFNB24 enhanced biomass production by 84.6%, and rice rhizosphere soils inoculated with Herbaspirillum sp. RFNB26 exhibited the highest nitrogenase activity. Our findings indicate that most of the selected strains possess multiple PGP properties that significantly improve the growth parameters of the two plants when tested under controlled conditions.

Mn(II)-coordinated Fluorescent Carbon Dots: Preparation and Discrimination of Organic Solvents

NASA Astrophysics Data System (ADS)

Wang, Yuru; Wang, Tianren; Chen, Xi; Xu, Yang; Li, Huanrong

2018-04-01

Herein, we prepared a Mn(II)-coordinated carbon dots (CDs) with fluorescence and MRI (magnetic resonance imaging) bimodal properties by a one-pot solvothermal method and separated via silica column chromatography. The quantum yield of the CDs increased greatly from 2.27% to 6.75% with increase of Mn(II) doping, meanwhile the CDs exhibited a higher MR activity (7.28 mM-1s-1) than that of commercial Gd-DTPA (4.63 mM-1s-1). In addition, white light emitting CDs were obtained by mixing the different types of CDs. Notably, these CDs exhibited different fluorescence emissions in different organic solvents and could be used to discriminate organic solvents based on the polarity and protonation of the solvents.

Sherrington's Model of Successive Induction for Comparative Analysis of Zebrafish Motor Response

EPA Science Inventory

The responses in motor activity of zebrafish to sudden changes in lighting conditions may be modeled by Sherrington’s model of successive induction. Fish left in the dark exhibit very little motion, when exposed to light zebrafish motion increases towards an apparent horizo...

Fun with Flukes: The Use of ICT in the Study of Larval Trematode Behaviour.

ERIC Educational Resources Information Center

Rea, J. G.; Irwin, S. W. B.

2001-01-01

Recommends a number of investigations using video-capture and two readily available, non-pathogenic larval Digeneans with contrasting life cycles and behavior. The activities support the hypothesis that parasites exhibit behavior that increases their chances of a host infection. (DDR)

Smolting in coastal cutthroat trout Onchorhynchus clarkii clarkii

USGS Publications Warehouse

Zydlewski, Joseph D.; Zydlewski, G.; Kennedy, B.; Gale, W.

2014-01-01

Gill Na+, K+-ATPase activity, condition factor and seawater (SW) challenges were used to assess the development of smolt characteristics in a cohort of hatchery coastal cutthroat trout Oncorhynchus clarkii clarkii from the Cowlitz River in Washington State, U.S.A. Gill Na+, K+-ATPase activity increased slightly in the spring, coinciding with an increase in hypo-osmoregulatory ability. These changes were of lesser magnitude than are observed in other salmonine species. Even at the peak of tolerance, these fish exhibited notable osmotic perturbations in full strength SW. Condition factor in these hatchery fish declined steadily through the spring. Wild captured migrants from four tributaries of the Columbia River had moderately elevated gill Na+, K+-ATPase activity, consistent with smolt development and with greater enzyme activity than autumn captured juveniles from one of the tributaries, Abernathy Creek. Migrant fish also had reduced condition factor. General linear models of 7 years of data from Abernathy Creek suggest that yearly variation, advancing photoperiod (as ordinal date) and fish size (fork length) were significant factors for predicting gill Na+, K+-ATPase activity in these wild fish. Both yearly variation and temperature were significant factors for predicting condition factor. These results suggest that coastal O. c. clarkii exhibit weakly developed characteristics of smolting. These changes are influenced by environmental conditions with great individual variation. The data suggest great physiological plasticity consistent with the variable life-history tactics observed in this species.

Effects of MAOA-genotype, alcohol consumption, and aging on violent behavior.

PubMed

Tikkanen, Roope; Sjöberg, Rickard L; Ducci, Francesca; Goldman, David; Holi, Matti; Tiihonen, Jari; Virkkunen, Matti

2009-03-01

Environmental factors appear to interact with a functional polymorphism (MAOA-LPR) in the promoter region of the monoamine oxidase A gene (MAOA) in determining some forms of antisocial behavior. However, how MAOA-LPR modulates the effects of other factors such as alcohol consumption related to antisocial behavior is not completely understood. This study examines the conjunct effect of MAOA-LPR, alcohol consumption, and aging on the risk for violent behavior. Recidivism in severe impulsive violent behavior was assessed after 7 to 15 years in a sample of 174 Finnish alcoholic offenders, the majority of whom exhibited antisocial or borderline personality disorder or both, and featured impulsive temperament traits. The risk for committing new acts of violence increased by 2.3% for each kilogram of increase in yearly mean alcohol consumption (p = 0.004) and decreased by 7.3% for every year among offenders carrying the high activity MAOA genotype. In contrast, alcohol consumption and aging failed to affect violent behavior in the low activity MAOA genotyped offenders. MAOA-LPR showed no main effect on the risk for recidivistic violence. Violent offenders carrying the high activity MAOA genotype differ in several ways from carriers with the low activity MAOA risk allele previously associated with antisocial behavior. Finnish high activity MAOA genotyped risk alcoholics exhibiting antisocial behavior, high alcohol consumption, and abnormal alcohol-related impulsive and uncontrolled violence might represent an etiologically distinct alcohol dependence subtype.

Oestrogen-deficient female aromatase knockout (ArKO) mice exhibit depressive-like symptomatology.

PubMed

Dalla, C; Antoniou, K; Papadopoulou-Daifoti, Z; Balthazart, J; Bakker, J

2004-07-01

We recently found that female aromatase knockout (ArKO) mice that are deficient in oestradiol due to a targeted mutation in the aromatase gene show deficits in sexual behaviour that cannot be corrected by adult treatment with oestrogens. We determined here whether these impairments are associated with changes in general levels of activity, anxiety or 'depressive-like' symptomatology due to chronic oestrogen deficiency. We also compared the neurochemical profile of ArKO and wild-type (WT) females, as oestrogens have been shown to modulate dopaminergic, serotonergic and noradrenergic brain activities. ArKO females did not differ from WT in spontaneous motor activity, exploration or anxiety. These findings are in line with the absence of major neurochemical alterations in hypothalamus, prefrontal cortex or striatum, which are involved in the expression of these behaviours. By contrast, ArKO females displayed decreased active behaviours, such as struggling and swimming, and increased passive behaviours, such as floating, in repeated sessions of the forced swim test, indicating that these females exhibit 'depressive-like' symptoms. Adult treatment with oestradiol did not reverse the behavioural deficits observed in the forced swim test, suggesting that they may be due to the absence of oestradiol during development. Accordingly, an increased serotonergic activity was observed in the hippocampus of ArKO females compared with WT, which was also not reversed by adult oestradiol treatment. The possible organizational role of oestradiol on the hippocampal serotonergic system and the 'depressive-like' profile of ArKO females provide new insights into the pathophysiology of depression and the increased vulnerability of women to depression.

Developmental trajectory of contextual learning and 24-h acetylcholine release in the hippocampus

PubMed Central

Takase, Kenkichi; Sakimoto, Yuya; Kimura, Fukuko; Mitsushima, Dai

2014-01-01

To determine the developmental trajectory of hippocampal function in rats, we examined 24-h changes in extracellular acetylcholine (ACh) levels and contextual learning performance. Extracellular ACh significantly correlated with spontaneous behavior, exhibiting a 24-h rhythm in juvenile (4-week-old), pubertal (6-week-old), and adult (9- to 12-week-old) rats. Although juveniles of both sexes exhibited low ACh levels, adult males had higher ACh levels than adult females. Moreover, juveniles exhibited much more spontaneous activity than adults when they showed equivalent ACh levels. Similarly, juveniles of both sexes exhibited relatively low contextual learning performance. Because contextual learning performance was significantly increased only in males, adult males exhibited better performance than adult females. We also observed a developmental relationship between contextual learning and ACh levels. Scopolamine pretreatment blocked contextual learning and interrupted the correlation. Since long-term scopolamine treatment after weaning impaired contextual learning in juveniles, the cholinergic input may participate in the development of hippocampus. PMID:24435246

Recovery of Active and Efficient Photocatalytic H 2 Production for CdSe Quantum Dots

DOE PAGES

Burke, Rebeckah; Cogan, Nicole M. Briglio; Oi, Aidan; ...

2018-05-07

Recently, colloidal semiconductor quantum dots (QDs) have shown great promise as photocatalysts for the production of chemical fuels by sunlight. Here, the efficiency of photocatalytic hydrogen (H 2) production for integrated systems of large diameter (4.4 nm) CdSe QDs as light harvesting nanoparticles with varying concentrations of nickel-dihydrolipoic acid (Ni-DHLA) small molecule catalysts was measured. While exhibiting excellent robustness and longevity, the efficiency of H 2 production for equimolar catalyst and QDs was relatively poor. However, the efficiency was found to increase substantially with increasing Ni-DHLA:QD molar ratios Surprisingly, this high activity was only observed with the use of 3-mercaptopropionicmore » acid (MPA) ligands, while CdSe QDs capped with dihydrolipoic acid (DHLA) exhibited poor performance in comparison, indicating that the QD capping ligand has a substantial impact on the catalytic performance. Finally, ultrafast transient absorption spectroscopic measurements of the electron transfer (ET) dynamics show fast ET to the catalyst. Importantly, an increase in ET efficiency is observed as the catalyst concentration is increased. Together, these results suggest that for these large QDs, tailoring the QD surface environment for facile ET and increasing catalyst concentrations increases the probability of ET from QDs to Ni-DHLA, overcoming the relatively small driving force for ET and decreased surface electron density for large diameter QDs.« less

Recovery of Active and Efficient Photocatalytic H 2 Production for CdSe Quantum Dots

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burke, Rebeckah; Cogan, Nicole M. Briglio; Oi, Aidan

Recently, colloidal semiconductor quantum dots (QDs) have shown great promise as photocatalysts for the production of chemical fuels by sunlight. Here, the efficiency of photocatalytic hydrogen (H 2) production for integrated systems of large diameter (4.4 nm) CdSe QDs as light harvesting nanoparticles with varying concentrations of nickel-dihydrolipoic acid (Ni-DHLA) small molecule catalysts was measured. While exhibiting excellent robustness and longevity, the efficiency of H 2 production for equimolar catalyst and QDs was relatively poor. However, the efficiency was found to increase substantially with increasing Ni-DHLA:QD molar ratios Surprisingly, this high activity was only observed with the use of 3-mercaptopropionicmore » acid (MPA) ligands, while CdSe QDs capped with dihydrolipoic acid (DHLA) exhibited poor performance in comparison, indicating that the QD capping ligand has a substantial impact on the catalytic performance. Finally, ultrafast transient absorption spectroscopic measurements of the electron transfer (ET) dynamics show fast ET to the catalyst. Importantly, an increase in ET efficiency is observed as the catalyst concentration is increased. Together, these results suggest that for these large QDs, tailoring the QD surface environment for facile ET and increasing catalyst concentrations increases the probability of ET from QDs to Ni-DHLA, overcoming the relatively small driving force for ET and decreased surface electron density for large diameter QDs.« less

Cognitive slowing in Parkinson disease is accompanied by hypofunctioning of the striatum.

PubMed

Sawamoto, N; Honda, M; Hanakawa, T; Aso, T; Inoue, M; Toyoda, H; Ishizu, K; Fukuyama, H; Shibasaki, H

2007-03-27

To investigate whether cognitive slowing in Parkinson disease (PD) reflects disruption of the basal ganglia or dysfunction of the frontal lobe by excluding an influence of abnormal brain activity due to motor deficits. We measured neuronal activity during a verbal mental-operation task with H(2)(15)O PET. This task enabled us to evaluate brain activity change associated with an increase in the cognitive speed without an influence on motor deficits. As the speed of the verbal mental-operation task increased, healthy controls exhibited proportional increase in activities in the anterior striatum and medial premotor cortex, suggesting the involvement of the corticobasal ganglia circuit in normal performance of the task. By contrast, patients with PD lacked an increase in the striatal activity, whereas the medial premotor cortex showed a proportional increase. Although the present study chose a liberal threshold and needs subsequent confirmation, the findings suggest that striatal disruption resulting in abnormal processing in the corticobasal ganglia circuit may contribute to cognitive slowing in Parkinson disease, as is the case in motor slowing.

Use of the vital stain FUN-1 indicates viability of Phytophthora capsici propagules and can be used to predict maximum zoospore production.

PubMed

Lewis Ivey, Melanie L; Miller, Sally A

2014-01-01

The fluorescent vital dye FUN®-1 (2-chloro-4-[2,3-dihydro-3-methyl-{benzo-1,3-thiazol-2-yl}-methylidene]-1-phenylquinolinium iodide) was evaluated as a tool to assess Phytophthora capsici sporangia and zoospore metabolic activity and viability. Under aerobic conditions, mycelia, sporangia and zoospores cultured on agar medium and stained with FUN-1 exhibited red fluorescent cylindrical intravacuolar structures (CIVS) that were clearly visible at 100× magnification. Encysted zoospores did not exhibit CIVS after exposure to FUN-1 dye. Over 7 d there was a significant reduction in the percent of sporangia containing CIVS, which corresponded with a significant increase in zoospore formation and release. The decline in the percentage of metabolically active sporangia and increase in the number of zoospores fit both a linear and log regression model. The FUN-1 dye was suitable for distinguishing between live and dead sporangia and effective in monitoring the change in metabolic activity of sporangia over time. It will be useful in determining parameters, including P. capsici culture age, that maximize production of zoospores in vitro.

Baselines and Degradation of Coral Reefs in the Northern Line Islands

PubMed Central

Sandin, Stuart A.; Smith, Jennifer E.; DeMartini, Edward E.; Dinsdale, Elizabeth A.; Donner, Simon D.; Friedlander, Alan M.; Konotchick, Talina; Malay, Machel; Maragos, James E.; Obura, David; Pantos, Olga; Paulay, Gustav; Richie, Morgan; Rohwer, Forest; Schroeder, Robert E.; Walsh, Sheila; Jackson, Jeremy B. C.; Knowlton, Nancy; Sala, Enric

2008-01-01

Effective conservation requires rigorous baselines of pristine conditions to assess the impacts of human activities and to evaluate the efficacy of management. Most coral reefs are moderately to severely degraded by local human activities such as fishing and pollution as well as global change, hence it is difficult to separate local from global effects. To this end, we surveyed coral reefs on uninhabited atolls in the northern Line Islands to provide a baseline of reef community structure, and on increasingly populated atolls to document changes associated with human activities. We found that top predators and reef-building organisms dominated unpopulated Kingman and Palmyra, while small planktivorous fishes and fleshy algae dominated the populated atolls of Tabuaeran and Kiritimati. Sharks and other top predators overwhelmed the fish assemblages on Kingman and Palmyra so that the biomass pyramid was inverted (top-heavy). In contrast, the biomass pyramid at Tabuaeran and Kiritimati exhibited the typical bottom-heavy pattern. Reefs without people exhibited less coral disease and greater coral recruitment relative to more inhabited reefs. Thus, protection from overfishing and pollution appears to increase the resilience of reef ecosystems to the effects of global warming. PMID:18301734

Ongoing modification of Mediterranean Pleistocene sapropels mediated by prokaryotes.

PubMed

Coolen, Marco J L; Cypionka, Heribert; Sass, Andrea M; Sass, Henrik; Overmann, Jörg

2002-06-28

Late Pleistocene organic-rich sediments (sapropels) from the eastern Mediterranean Sea harbor unknown, metabolically active chemoorganotrophic prokaryotes. As compared to the carbon-lean intermediate layers, sapropels exhibit elevated cell numbers, increased activities of hydrolytic exoenzymes, and increased anaerobic glucose degradation rates, suggesting that microbial carbon substrates originate from sapropel layers up to 217,000 years old. 16S ribosomal RNA gene analyses revealed that as-yet-uncultured green nonsulfur bacteria constitute up to 70% of the total microbial biomass. Crenarchaeota constitute a smaller fraction (on average, 16%). A slow but significant turnover of glucose could be detected. Apparently, sapropels are still altered by the metabolic activity of green nonsulfur bacteria and crenarchaeota.

pH Effects on solubility, zeta potential, and correlation between antibacterial activity and molecular weight of chitosan.

PubMed

Chang, Shun-Hsien; Lin, Hong-Ting Victor; Wu, Guan-James; Tsai, Guo Jane

2015-12-10

Six chitosans with molecular weights (MWs) of 300, 156, 72.1, 29.2, 7.1, and 3.3 kDa were prepared by cellulase degradation of chitosan (300 kDa) and ultrafiltration techniques. We examined the correlation between activity against Escherichia coli and Staphylococcus aureus and chitosan MW, and provided the underlying explanation. In acidic pH conditions, the chitosan activity increased with increasing MW, irrespective of the temperature and bacteria tested. However, at neutral pH, chitosan activity increased as the MW decreased, and little activity was observed for chitosans with MW >29.2 kDa. At pH 5.0 and 6.0, chitosans exhibited good water solubility and zeta potential (ZP) decreased with the MW, whereas the solubility and ZP of the chitosans decreased with increasing MW at pH 7.0. Particularly, low solubility and negative ZP values were determined for chitosans with MW >29.2 kDa, which may explain the loss of their antibacterial activity at pH 7.0. Copyright © 2015 Elsevier Ltd. All rights reserved.

Zn uptake, physiological response and stress attenuation in mycorrhizal jack bean growing in soil with increasing Zn concentrations.

PubMed

Andrade, Sara A L; Gratão, Priscila L; Schiavinato, Marlene A; Silveira, Adriana P D; Azevedo, Ricardo A; Mazzafera, Paulo

2009-06-01

The influence of arbuscular mycorrhizal fungi (AMF) inoculation on Canavalia ensiformis growth, nutrient and Zn uptake, and on some physiological parameters in response to increasing soil Zn concentrations was studied. Treatments were applied in seven replicates in a 2 x 4 factorial design, consisting of the inoculation or not with the AMF Glomus etunicatum, and the addition of Zn to soil at the concentrations of 0, 100, 300 and 900 mg kg(-1). AMF inoculation enhanced the accumulation of Zn in tissues and promoted biomass yields and root nodulation. Mycorrhizal plants exhibited relative tolerance to Zn up to 300 mg kg(-1) without exhibiting visual symptoms of toxicity, in contrast to non-mycorrhizal plants which exhibited a significant growth reduction at the same soil Zn concentration. The highest concentration of Zn added to soil was highly toxic to the plants. Leaves of plants grown in high Zn concentration exhibited a Zn-induced proline accumulation and also an increase in soluble amino acid contents; however proline contents were lower in mycorrhizal jack beans. Plants in association or not with the AMF exhibited marked differences in the foliar soluble amino acid profile and composition in response to Zn addition to soil. In general, Zn induced oxidative stress which could be verified by increased lipid peroxidation rates and changes in catalase, ascorbate peroxidase, glutathione reductase and superoxide dismutase activities. In summary, G. etunicatum was able to maintain an efficient symbiosis with jack bean plants in moderately contaminated Zn-soils, improving plant performance under those conditions, which is likely to be due to a combination of physiological and nutritional changes caused by the intimate relation between fungus and plant. The enhanced Zn uptake by AMF inoculated jack bean plants might be of interest for phytoremediation purposes.

Immobilization Increases the Stability and Reusability of Pigeon Pea NADP+ Linked Glucose-6-Phosphate Dehydrogenase.

PubMed

Singh, Siddhartha; Singh, Amit Kumar; Singh, M Chandrakumar; Pandey, Pramod Kumar

2017-02-01

Immobilization of enzymes is valuably important as it improves the stability and hence increases the reusability of enzymes. The present investigation is an attempt for immobilization of purified glucose-6-phosphate dehydrogenase from pigeon pea on different matrix. Maximum immobilization was achieved when alginate was used as immobilization matrix. As compared to soluble enzyme the alginate immobilized enzyme exhibited enhanced optimum pH and temperature. The alginate immobilized enzyme displayed more than 80% activity up to 7 continuous reactions and more than 50% activity up to 11 continuous reactions.

Synthesis of fruity ethyl esters by acyl coenzyme A: alcohol acyltransferase and reverse esterase activities in Oenococcus oeni and Lactobacillus plantarum.

PubMed

Costello, P J; Siebert, T E; Solomon, M R; Bartowsky, E J

2013-03-01

To assess the abilities of commercial wine lactic acid bacteria (LAB) to synthesize potentially flavour active fatty acid ethyl esters and determine mechanisms involved in their production. Oenococcus oeni AWRI B551 produced significant levels of ethyl hexanoate and ethyl octanoate following growth in an ethanolic test medium, and ester formation generally increased with increasing pH (4.5 > 3.5), anaerobiosis and precursor supplementation. Cell-free extracts of commercial O. oeni strains and Lactobacillus plantarum AWRI B740 were also tested for ester-synthesizing capabilities in a phosphate buffer via: (i) acyl coenzyme A: alcohol acyltransferase (AcoAAAT) activity and (ii) reverse esterase activity. For both ester-synthesizing activities, strain-dependent variation was observed, with AcoAAAT activity generally greater than reverse esterase. Reverse esterase in O. oeni AWRI B551 also esterified 1-propanol to produce propyl octanoate, and deuterated substrates ([(2)H(6)]ethanol and [(2)H(15)]octanoic acid) to produce the fully deuterated ester, [(2)H(5)]ethyl [(2)H(15)]octanoate. Wine LAB exhibit ethyl ester-synthesizing capability and possess two different ester-synthesizing activities, one of which is associated with an acyl coenzyme A: alcohol acyltransferase. This study demonstrates that wine LAB exhibit enzyme activities that can augment the ethyl ester content of wine. This knowledge will facilitate greater control over the impacts of malolactic fermentation on the fruity sensory properties and quality of wine. © 2012 Australian Wine Research Institute © 2012 The Society for Applied Microbiology.

Multichannel brain recordings in behaving Drosophila reveal oscillatory activity and local coherence in response to sensory stimulation and circuit activation

PubMed Central

Paulk, Angelique C.; Zhou, Yanqiong; Stratton, Peter; Liu, Li

2013-01-01

Neural networks in vertebrates exhibit endogenous oscillations that have been associated with functions ranging from sensory processing to locomotion. It remains unclear whether oscillations may play a similar role in the insect brain. We describe a novel “whole brain” readout for Drosophila melanogaster using a simple multichannel recording preparation to study electrical activity across the brain of flies exposed to different sensory stimuli. We recorded local field potential (LFP) activity from >2,000 registered recording sites across the fly brain in >200 wild-type and transgenic animals to uncover specific LFP frequency bands that correlate with: 1) brain region; 2) sensory modality (olfactory, visual, or mechanosensory); and 3) activity in specific neural circuits. We found endogenous and stimulus-specific oscillations throughout the fly brain. Central (higher-order) brain regions exhibited sensory modality-specific increases in power within narrow frequency bands. Conversely, in sensory brain regions such as the optic or antennal lobes, LFP coherence, rather than power, best defined sensory responses across modalities. By transiently activating specific circuits via expression of TrpA1, we found that several circuits in the fly brain modulate LFP power and coherence across brain regions and frequency domains. However, activation of a neuromodulatory octopaminergic circuit specifically increased neuronal coherence in the optic lobes during visual stimulation while decreasing coherence in central brain regions. Our multichannel recording and brain registration approach provides an effective way to track activity simultaneously across the fly brain in vivo, allowing investigation of functional roles for oscillations in processing sensory stimuli and modulating behavior. PMID:23864378

Glutamatergic stimulation of the left dentate gyrus abolishes depressive-like behaviors in a rat learned helplessness paradigm.

PubMed

Seo, Jeho; Cho, Hojin; Kim, Gun Tae; Kim, Chul Hoon; Kim, Dong Goo

2017-10-01

Episodic experiences of stress have been identified as the leading cause of major depressive disorder (MDD). The occurrence of MDD is profoundly influenced by the individual's coping strategy, rather than the severity of the stress itself. Resting brain activity has been shown to alter in several mental disorders. However, the functional relationship between resting brain activity and coping strategies has not yet been studied. In the present study, we observed different patterns of resting brain activity in rats that had determined either positive (resilient to stress) or negative (vulnerable to stress) coping strategies, and examined whether modulation of the preset resting brain activity could influence the behavioral phenotype associated with negative coping strategy (i.e., depressive-like behaviors). We used a learned helplessness paradigm-a well-established model of MDD-to detect coping strategies. Differences in resting state brain activity between animals with positive and negative coping strategies were assessed using 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET). Glutamatergic stimulation was used to modulate resting brain activity. After exposure to repeated uncontrollable stress, seven of 23 rats exhibited positive coping strategies, while eight of 23 rats exhibited negative coping strategies. Increased resting brain activity was observed only in the left ventral dentate gyrus of the positive coping rats using FDG-PET. Furthermore, glutamatergic stimulation of the left dentate gyrus abolished depressive-like behaviors in rats with negative coping strategies. Increased resting brain activity in the left ventral dentate gyrus helps animals to select positive coping strategies in response to future stress. Copyright © 2016 Elsevier Inc. All rights reserved.

An Aqueous Extract of Marine Microalgae Exhibits Antimetastatic Activity through Preferential Killing of Suspended Cancer Cells and Anticolony Forming Activity

PubMed Central

Somasekharan, Syam Prakash; El-Naggar, Amal; Sorensen, Poul H.

2016-01-01

Research on marine natural products as potential anticancer agents is still limited. In the present study, an aqueous extract of a Canadian marine microalgal preparation was assessed for anticancer activities using various assays and cell lines of human cancers, including lung, prostate, stomach, breast, and pancreatic cancers, as well as an osteosarcoma. In vitro, the microalgal extract exhibited marked anticolony forming activity. In addition, it was more toxic, as indicated by increased apoptosis, to nonadherent cells (grown in suspension) than to adherent cells. In vivo, an antimetastatic effect of the extract was observed in NOD-SCID mice carrying subrenal capsule xenografts of PC3 prostate cancer cells. The results of the present study suggest that the antimetastatic effect of the aqueous microalgal extract is based on inhibition of colony forming ability of cancer cells and the preferential killing of suspended cancer cells. Further research aimed at identification of the molecular basis of the anticancer activities of the microalgal extract appears to be warranted. PMID:27656243

Antiviral Activity of Peanut (Arachis hypogaea L.) Skin Extract Against Human Influenza Viruses.

PubMed

Makau, Juliann Nzembi; Watanabe, Ken; Mohammed, Magdy M D; Nishida, Noriyuki

2018-05-30

The high propensity of influenza viruses to develop resistance to antiviral drugs necessitates the continuing search for new therapeutics. Peanut skins, which are low-value byproducts of the peanut industry, are known to contain high levels of polyphenols. In this study, we investigated the antiviral activity of ethanol extracts of peanut skins against various influenza viruses using cell-based assays. Extracts with a higher polyphenol content exhibited higher antiviral activities, suggesting that the active components are the polyphenols. An extract prepared from roasted peanut skins effectively inhibited the replication of influenza virus A/WSN/33 with a half maximal inhibitory concentration of 1.3 μg/mL. Plaque assay results suggested that the extract inhibits the early replication stages of the influenza virus. It demonstrated activity against both influenza type A and type B viruses. Notably, the extract exhibited a potent activity against a clinical isolate of the 2009 H1N1 pandemic, which had reduced sensitivity to oseltamivir. Moreover, a combination of peanut skin extract with the anti-influenza drugs, oseltamivir and amantadine, synergistically increased their antiviral activity. These data demonstrate the potential application of peanut skin extract in the development of new therapeutic options for influenza management.

Hemin/G-quadruplex structure and activity alteration induced by magnesium cations.

PubMed

Kosman, J; Juskowiak, B

2016-04-01

The influence of metal cations on G-quadruplex structure and peroxidase-mimicking DNAzyme activity was investigated. Experiments revealed a significant role of magnesium ion, which in the presence of potassium cation influenced DNAzyme activity. This ability has been associated with alteration of G-quadruplex topology and consequently affinity to bind hemin molecule. It has been demonstrated that G-quadruplex based on PS2.M sequence under these conditions formed parallel topology, which exhibited lower activity than that observed in standard potassium-containing solution. On the other hand DNAzyme/magnesium ion system based on telomeric sequence, which did not undergo significant structural changes, exhibited higher peroxidase activity upon magnesium ion addition. In both cases, the stabilization effect of magnesium cations on G-quadruplex structure was observed. The mechanism of DNAzyme activity alteration by magnesium ion can be explained by its influence on the pKa value of DNAzyme. Magnesium ion decreased pKa for PS2.M based system but increased it for telomeric DNAzyme. Magnesium cation effect on G-quadruplex structure as well as DNAzyme activity is particularly important since this ion is one of the most common metal cations in biological samples. Copyright © 2016 Elsevier B.V. All rights reserved.

In vivo antiulcer activity of the aqueous extract of Bauhinia purpurea leaf.

PubMed

Zakaria, Z A; Abdul Hisam, E E; Rofiee, M S; Norhafizah, M; Somchit, M N; Teh, L K; Salleh, M Z

2011-09-02

Bauhinia purpurea (Fabaceae) is a medicinal plant traditionally used to treat various ailments, including ulcers. In order to establish pharmacological properties of the leaf of Bauhinia purpurea, studies were performed on antiulcer activity of the plant's aqueous extract. The Bauhinia purpurea aqueous extract (BPAE) was prepared in the doses of 100, 500 and 1,000 mg/kg. Antiulcer activity of BPAE was evaluated by absolute ethanol- and indomethacin-induced gastric ulcer, and pyloric ligation models. Acute toxicity was also carried out. BPAE, at the dose of 5,000 mg/kg, did not cause any signs of toxicity to rats when given orally. Oral administration of BPAE exhibited antiulcer activity (p<0.05) in all models used. However, the dose-dependent activity was observed only in the absolute ethanol-induced gastric ulcer model. Histological studies supported the observed antiulcer activity of BPAE. In pyloric ligation assay, BPAE increased the gastric wall mucus secretion. The BPAE exhibits antiulcer activity, which could be due to the presence of saponins or sugar-free polyphenols, and, thus, confirmed the traditional uses of Bauhinia purpurea in the treatment of ulcers. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Expression of a Heterologous S-Adenosylmethionine Decarboxylase cDNA in Plants Demonstrates That Changes in S-Adenosyl-l-Methionine Decarboxylase Activity Determine Levels of the Higher Polyamines Spermidine and Spermine1

PubMed Central

Thu-Hang, Pham; Bassie, Ludovic; Safwat, Gehan; Trung-Nghia, Pham; Christou, Paul; Capell, Teresa

2002-01-01

We posed the question of whether steady-state levels of the higher polyamines spermidine and spermine in plants can be influenced by overexpression of a heterologous cDNA involved in the later steps of the pathway, in the absence of any further manipulation of the two synthases that are also involved in their biosynthesis. Transgenic rice (Oryza sativa) plants engineered with the heterologous Datura stramonium S-adenosylmethionine decarboxylase (samdc) cDNA exhibited accumulation of the transgene steady-state mRNA. Transgene expression did not affect expression of the orthologous samdc gene. Significant increases in SAMDC activity translated to a direct increase in the level of spermidine, but not spermine, in leaves. Seeds recovered from a number of plants exhibited significant increases in spermidine and spermine levels. We demonstrate that overexpression of the D. stramonium samdc cDNA in transgenic rice is sufficient for accumulation of spermidine in leaves and spermidine and spermine in seeds. These findings suggest that increases in enzyme activity in one of the two components of the later parts of the pathway leading to the higher polyamines is sufficient to alter their levels mostly in seeds and, to some extent, in vegetative tissue such as leaves. Implications of our results on the design of rational approaches for the modulation of the polyamine pathway in plants are discussed in the general framework of metabolic pathway engineering. PMID:12177487

GROWTH AND DEVELOPMENT SYMPOSIUM: Adenosine monophosphate-activated protein kinase and mitochondria in Rendement Napole pig growth.

PubMed

Scheffler, T L; Gerrard, D E

2016-09-01

The Rendement Napole mutation (RN-), which is well known to influence pork quality, also has a profound impact on metabolic characteristics of muscle. Pigs with RN- possess a SNP in the γ3 subunit of adenosine monophosphate (AMP)-activated protein kinase (AMPK); AMPK, a key energy sensor in skeletal muscle, modulates energy producing and energy consuming pathways to maintain cellular homeostasis. Importantly, AMPK regulates not only acute response to energy stress but also facilitates long-term adaptation via changes in gene and protein expression. The RN- allele increases AMPK activity, which alters the metabolic phenotype of skeletal muscle by increasing mitochondrial content and oxidative capacity. Fibers with greater oxidative capacity typically exhibit increased protein turnover and smaller fiber size, which indicates that RN- pigs may exhibit decreased efficiency and growth potential. However, whole body and muscle growth of RN- pigs appear similar to that of wild-type pigs and despite increased oxidative capacity, fibers maintain the capacity for hypertrophic growth. This indicates that compensatory mechanisms may allow RN- pigs to achieve rates of muscle growth similar to those of wild-type pigs. Intriguingly, lipid oxidation and mitochondria function are enhanced in RN- pig muscle. Thus far, characteristics of RN- muscle are largely based on animals near market weight. To better understand interaction between energy signaling and protein accretion in muscle, further work is needed to define age-dependent relationships between AMPK signaling, metabolism, and muscle growth.

Transport systems of Ventricaria ventricosa: asymmetry of the hyper- and hypotonic regulation mechanisms.

PubMed

Bisson, M A; Beilby, M J

2008-01-01

Hyper- and hypotonic stresses elicit apparently symmetrical responses in the alga Ventricaria. With hypertonic stress, membrane potential difference (PD) between the vacuole and the external medium becomes more positive, conductance at positive PDs (Gmpos) increases and KCl is actively taken up to increase turgor. With hypotonic stress, the membrane PD becomes more negative, conductance at negative PDs (Gmneg) increases and KCl is lost to decrease turgor. We used inhibitors that affect active transport to determine whether agents that inhibit the K(+) pump and hypertonic regulation also inhibit hypotonic regulatory responses. Cells whose turgor pressure was held low by the pressure probe (turgor-clamped) exhibited the same response as cells challenged by hyperosmotic medium, although the response was maintained longer than in osmotically challenged cells, which regulate turgor. The role of active K(+) transport was confirmed by the effects of decreased light, dichlorophenyldimethyl urea and diethylstilbestrol, which induced a uniformly low conductance (quiet state). Cells clamped to high turgor exhibited the same response as cells challenged by hypo-osmotic medium, but the response was similarly transient, making effects of inhibitors hard to determine. Unlike clamped cells, cells challenged by hypo-osmotic medium responded to inhibitors with rapid, transient, negative-going PDs, with decreased Gmneg and increased Gmpos (linearized I-V), achieving the quiet state as PD recovered. These changes are different from those exerted on the pump state, indicating that different transport systems are responsible for turgor regulation in the two cases.

Dexamethasone effects on creatine kinase activity and insulin-like growth factor receptors in cultured muscle cells

NASA Technical Reports Server (NTRS)

Whitson, Peggy A.; Stuart, Charles A.; Huls, M. H.; Sams, Clarence F.; Cintron, Nitza M.

1989-01-01

The effect of dexamethasone on the activity of creatine kinase (CK) and the insulin-like growth factor I (IGF-I) binding were investigated using skeletal- and cardiac-muscle-derived cultured cell lines (mouse, C2C12; rat, L6 and H9c2). It was found that, in skeletal muscle cells, dexamethasone treatment during differentiation of skeletal-muscle cells caused dose-dependent increases in CK activity and increases in the degree of myotube formation, whereas cardiac cells (H9c2) exhibited very low CK activity during culture or dexamethasone treatment. Results for IGF-I binding were similar in all three cell lines. The IGF-I binding to dexamethasone-treated cells (50 nM for 24 hr on the day prior to confluence) resulted in an increased number of available binding sites, with no effect on the binding affinities.

The psychophysiology of crying.

PubMed

Gross, J J; Frederickson, B L; Levenson, R W

1994-09-01

Two conflicting views have emerged as to why people cry when they are sad. One suggests that crying serves homeostasis by facilitating recovery; the other suggests that crying produces an aversive high-arousal state that motivates behavior aimed at ending the tears. To test hypotheses drawn from these views, we showed a short film known to elicit sadness to 150 women. During this film, 33 subjects spontaneously cried and 117 did not. Subjects who cried exhibited more expressive behavior and reported feeling more sadness and pain than did subjects who did not cry. Crying also was associated with increases in somatic and autonomic nervous system activity. The increases in autonomic activity could not be accounted for solely by the increases in somatic activity. Crying is thus associated with an aversive state, including negative emotion and a complex mixture of sympathetic, parasympathetic, and somatic activation, and we speculate about the functional implications of these findings.

Cloning, overexpression, purification of bacteriocin enterocin-B and structural analysis, interaction determination of enterocin-A, B against pathogenic bacteria and human cancer cells.

PubMed

Ankaiah, Dasari; Palanichamy, Esakkiraj; Antonyraj, Christian Bharathi; Ayyanna, Repally; Perumal, Venkatesh; Ahamed, Syed Ibrahim Basheer; Arul, Venkatesan

2018-05-02

In this present study, a gene (ent-B) encoding the bacteriocin enterocin-B was cloned, overexpressed and purified from Enterococcus faecium por1. The molecular weight of the bacteriocin enterocin-B was observed around 7.2 kDa and exhibited antimicrobial activity against several human pathogenic bacteria. The antimicrobial activity of cloned enterocin-B was increased effectively by combining with another bacteriocin enterocin-A from the same microorganism. Protein-protein docking and molecular dynamics simulation studies revealed that the bacteriocin enterocin-B is interacting with enterocin-A and formation of a heterodimer (enterocin A + B). The heterodimer of bacteriocin enterocin-A + B exhibited potential anti-bacterial, anti-biofilm activity against Staphylococcus aureus, Acinetobacter baumannii, Listeria monocytogenes and Escherichia coli. The bacteriocin enterocin-B, A and heterodimer of bacteriocin enterocin A + B showed no haemolysis on human RBC cells. This is the first report that the cell growth inhibitory activity of the bacteriocin enterocin B against HeLa, HT-29 and AGS human cancer cells and this cell growth inhibitory activity was significantly increased when cancer cells treated with the heterodimer of bacteriocins enterocin-A + B. The cell growth inhibitory activity of the bacteriocin enterocin-B and the heterodimer of bacteriocin enterocin-A + B were not observed in non-cancerous INT-407 cells (intestinal epithelial cells). Copyright © 2018. Published by Elsevier B.V.

Structure and activity of the Pseudomonas aeruginosa hotdog-fold thioesterases PA5202 and PA2801.

PubMed

Gonzalez, Claudio F; Tchigvintsev, Anatoli; Brown, Greg; Flick, Robert; Evdokimova, Elena; Xu, Xiaohui; Osipiuk, Jerzy; Cuff, Marianne E; Lynch, Susan; Joachimiak, Andrzej; Savchenko, Alexei; Yakunin, Alexander F

2012-06-15

The hotdog fold is one of the basic protein folds widely present in bacteria, archaea and eukaryotes. Many of these proteins exhibit thioesterase activity against fatty acyl-CoAs and play important roles in lipid metabolism, cellular signalling and degradation of xenobiotics. The genome of the opportunistic pathogen Pseudomonas aeruginosa contains over 20 genes encoding predicted hotdog-fold proteins, none of which have been experimentally characterized. We have found that two P. aeruginosa hotdog proteins display high thioesterase activity against 3-hydroxy-3-methylglutaryl-CoA and glutaryl-CoA (PA5202), and octanoyl-CoA (PA2801). Crystal structures of these proteins were solved (at 1.70 and 1.75 Å for PA5202 and PA2801 respectively) and revealed a hotdog fold with a potential catalytic carboxylate residue located on the long α-helix (Asp(57) in PA5202 and Glu(35) in PA2801). Alanine residue replacement mutagenesis of PA5202 identified four residues (Asn(42), Arg(43), Asp(57) and Thr(76)) that are critical for its activity and are located in the active site. A P. aeruginosa PA5202 deletion strain showed an increased secretion of the antimicrobial pigment pyocyanine and an increased expression of genes involved in pyocyanin biosynthesis, suggesting a functional link between PA5202 activity and pyocyanin production. Thus the P. aeruginosa hotdog thioesterases PA5202 and PA2801 have similar structures, but exhibit different substrate preferences and functions.

Ixora parviflora Protects against UVB-Induced Photoaging by Inhibiting the Expression of MMPs, MAP Kinases, and COX-2 and by Promoting Type I Procollagen Synthesis

PubMed Central

Wen, Kuo-Ching; Fan, Pei-Ching; Tsai, Shang-Yuan; Shih, I-Chen; Chiang, Hsiu-Mei

2012-01-01

Ixora parviflora with high polyphenol content exhibited antioxidant activity and reducing UVB-induced intracellular reactive oxygen species production. In this study, results of the photoaging screening experiments revealed that IPE at 1000 μg/mL reduced the activity of bacterial collagenase by 92.7 ± 4.2% and reduced the activity of elastase by 32.6 ± 1.4%. Therefore, we investigated the mechanisms by which IPE exerts its anti-photoaging activity. IPE at 1 μg/mL led to an increase in type I procollagen expression and increased total collagen synthesis in fibroblasts at 5 μg/mL. We found that IPE inhibited MMP-1, MMP-3, and MMP-9 expression at doses of 1, 5, and 10 μg/mL, respectively, in fibroblasts exposed to UV irradiation (40 mJ/cm2). Gelatin zymography assay showed that IPE at 50 μg/mL inhibited MMP-9 secretion/activity in cultured fibroblasts after UVB exposure. In addition, IPE inhibited the phosphorylation of p38, ERK, and JNK induced by UVB. Furthermore, IPE inhibited the UVB-induced expression of Smad7. In addition, IPE at 1 μg/mL inhibited NO production and COX-2 expression in UV-exposed fibroblasts. These findings show that IPE exhibits anti-inflammatory and anti-photoaging activities, indicating that IPE could be a potential anti-aging agent. PMID:22203872

Ixora parviflora Protects against UVB-Induced Photoaging by Inhibiting the Expression of MMPs, MAP Kinases, and COX-2 and by Promoting Type I Procollagen Synthesis.

PubMed

Wen, Kuo-Ching; Fan, Pei-Ching; Tsai, Shang-Yuan; Shih, I-Chen; Chiang, Hsiu-Mei

2012-01-01

Ixora parviflora with high polyphenol content exhibited antioxidant activity and reducing UVB-induced intracellular reactive oxygen species production. In this study, results of the photoaging screening experiments revealed that IPE at 1000 μg/mL reduced the activity of bacterial collagenase by 92.7 ± 4.2% and reduced the activity of elastase by 32.6 ± 1.4%. Therefore, we investigated the mechanisms by which IPE exerts its anti-photoaging activity. IPE at 1 μg/mL led to an increase in type I procollagen expression and increased total collagen synthesis in fibroblasts at 5 μg/mL. We found that IPE inhibited MMP-1, MMP-3, and MMP-9 expression at doses of 1, 5, and 10 μg/mL, respectively, in fibroblasts exposed to UV irradiation (40 mJ/cm(2)). Gelatin zymography assay showed that IPE at 50 μg/mL inhibited MMP-9 secretion/activity in cultured fibroblasts after UVB exposure. In addition, IPE inhibited the phosphorylation of p38, ERK, and JNK induced by UVB. Furthermore, IPE inhibited the UVB-induced expression of Smad7. In addition, IPE at 1 μg/mL inhibited NO production and COX-2 expression in UV-exposed fibroblasts. These findings show that IPE exhibits anti-inflammatory and anti-photoaging activities, indicating that IPE could be a potential anti-aging agent.

Glucose ingestion stimulates atherothrombotic inflammation in polycystic ovary syndrome

PubMed Central

Kirwan, John P.; Rote, Neal S.; Minium, Judi

2013-01-01

Women with polycystic ovary syndrome (PCOS) have chronic low-grade inflammation that can increase the risk of atherothrombosis. We performed a cross-sectional study to examine the effect of glucose ingestion on markers of atherothrombotic inflammation in mononuclear cells (MNC) of 16 women with PCOS (8 lean, 8 obese) and 16 weight-matched controls. Activator protein-1 (AP-1) activation and the protein content of early growth response-1 (EGR-1), matrix matalloproteinases-2 (MMP2), and tissue factor (TF) were quantified from MNC obtained from blood drawn fasting and 2 h after glucose ingestion. Plasma MMP9 and C-reactive protein (CRP) were measured from fasting blood samples. Truncal fat was determined by DEXA. Lean women with PCOS exhibited greater AP-1 activation and MMP2 protein content after glucose ingestion and higher plasma MMP9 and CRP levels than lean controls. Obese women with PCOS exhibited greater EGR-1 and TF protein content after glucose ingestion, and plasma CRP levels were even higher compared with lean subjects regardless of PCOS status. Truncal fat correlated with MMP9 and CRP levels and glucose-stimulated increases in AP-1 activation and EGR-1 and TF protein content. Testosterone correlated with glucose-stimulated AP-1 activation, and androstenedione correlated with MMP9 and CRP levels and glucose-stimulated AP-1 activation. Thus, both PCOS and obesity contribute to an atherothrombotic state in which excess abdominal adiposity and hyperandrogenism may be specific risk factors for developing atherothrombosis. PMID:23249695

Compassionate Love Buffers Stress-Reactive Mothers from Fight-or-Flight Parenting

ERIC Educational Resources Information Center

Miller, Jonas G.; Kahle, Sarah; Lopez, Monica; Hastings, Paul D.

2015-01-01

The links among mothers' compassionate love for their child, autonomic nervous system activity, and parenting behavior during less and more challenging mother-child interactions were examined. Mothers expressed and reported less negative affect when they exhibited autonomic patterns of increased parasympathetic dominance (high parasympathetic…

Taking the "Physical" out of Physical Education

ERIC Educational Resources Information Center

Usher, Wayne; Keegan, Richard; Edwards, Allan

2016-01-01

Australian youth (5-17) are exhibiting the most alarming statistics surrounding poor physical activity (PA) levels and increasing correlating chronic disease trends (i.e. obesity). With schools well positioned to address such concerns, this study aimed to determine the type, frequency and intensity levels of PA being undertaken by children during…

Efficiency of the Prefrontal Cortex during Working Memory in Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Sheridan, Margaret A.; Hinshaw, Stephen; D'Esposito, Mark

2007-01-01

Objective: Previous research has demonstrated that during task conditions requiring an increase in inhibitory function or working memory, children and adults with attention-deficit/hyperactivity disorder (ADHD) exhibit greater and more varied prefrontal cortical(PFC) activation compared to age-matched control participants. This pattern may reflect…

Ts1Cje Down syndrome model mice exhibit environmental stimuli-triggered locomotor hyperactivity and sociability concurrent with increased flux through central dopamine and serotonin metabolism.

PubMed

Shimohata, Atsushi; Ishihara, Keiichi; Hattori, Satoko; Miyamoto, Hiroyuki; Morishita, Hiromasa; Ornthanalai, Guy; Raveau, Matthieu; Ebrahim, Abdul Shukkur; Amano, Kenji; Yamada, Kazuyuki; Sago, Haruhiko; Akiba, Satoshi; Mataga, Nobuko; Murphy, Niall P; Miyakawa, Tsuyoshi; Yamakawa, Kazuhiro

2017-07-01

Ts1Cje mice have a segmental trisomy of chromosome 16 that is orthologous to human chromosome 21 and display Down syndrome-like cognitive impairments. Despite the occurrence of affective and emotional impairments in patients with Down syndrome, these parameters are poorly documented in Down syndrome mouse models, including Ts1Cje mice. Here, we conducted comprehensive behavioral analyses, including anxiety-, sociability-, and depression-related tasks, and biochemical analyses of monoamines and their metabolites in Ts1Cje mice. Ts1Cje mice showed enhanced locomotor activity in novel environments and increased social contact with unfamiliar partners when compared with wild-type littermates, but a significantly lower activity in familiar environments. Ts1Cje mice also exhibited some signs of decreased depression like-behavior. Furthermore, Ts1Cje mice showed monoamine abnormalities, including increased extracellular dopamine and serotonin, and enhanced catabolism in the striatum and ventral forebrain. This study constitutes the first report of deviated monoamine metabolism that may help explain the basis for abnormal behaviors, including the environmental stimuli-triggered hyperactivity, increased sociability and decreased depression-like behavior in Ts1Cje mice. Copyright © 2017 Elsevier Inc. All rights reserved.

Hypoxia-activated prodrug enhances therapeutic effect of sunitinib in melanoma

PubMed Central

Liu, Shujing; Tetzlaff, Michael T.; Wang, Tao; Chen, Xiang; Yang, Ruifeng; Kumar, Suresh M.; Vultur, Adina; Li, Pengxiang; Martin, James S.; Herlyn, Meenhard; Amaravadi, Ravi

2017-01-01

Angiogenesis is a critical step during tumor progression. Anti-angiogenic therapy has only provided modest benefits in delaying tumor progression despite its early promise in cancer treatment. It has been postulated that anti-angiogenic therapy may promote the emergence of a more aggressive cancer cell phenotype by generating increased tumor hypoxia—a well-recognized promoter of tumor progression. TH-302 is a 2-nitroimidazole triggered hypoxia-activated prodrug (HAP) which has been shown to selectively target the hypoxic tumor compartment and reduce tumor volume. Here, we show that melanoma cells grown under hypoxic conditions exhibit increased resistance to a wide variety of therapeutic agents in vitro and generate larger and more aggressive tumors in vivo than melanoma cells grown under normoxic conditions. However, hypoxic melanoma cells exhibit a pronounced sensitivity to TH-302 which is further enhanced by the addition of sunitinib. Short term sunitinib treatment fails to prolong the survival of melanoma bearing genetically engineered mice (Tyr::CreER; BRafCA;Ptenlox/lox) but increases tumor hypoxia. Long term TH-302 alone modestly prolongs the overall survival of melanoma bearing mice. Combination therapy of TH-302 with sunitinib further increases the survival of treated mice. These studies provide a translational rationale for combining hypoxic tumor cell targeted therapies with anti-angiogenics for treatment of melanoma. PMID:29383148

Effects of heavy metal Cd pollution on microbial activities in soil.

PubMed

Shi, Weilin; Ma, Xiying

2017-12-23

Heavy metal contamination of soil occurs when heavy metals are introduced to soil through human activities, leading to the gradual deterioration of the ecology and environment. Microorganism activity reflects the intensity of various biochemical reactions in soil, and changes in it reflect the level of heavy metal pollution affecting the soil. The effects were studied of heavy metal Cd on the microbial activity of soil at different concentrations by investigating the respiratory intensity, urease activity, and catalase activity in forest soil and garden soil. The results showed that the respiratory intensity, urease and catalase activities in the garden soil were all higher than in the forest soil. Cd has obvious inhibitory effects on microbial activities. The three parameters exhibited a downward trend with increasing concentrations of Cd. Catalase activity increased when the mass concentration of Cd reached 1.0 mg/kg, indicating that low concentrations of Cd can promote the activity of some microorganisms. Respiratory intensity and urease activity also increased when the concentration reached 10.0 mg/kg, showing that respiratory intensity and urease activity have strong response mechanisms to adverse conditions. The effective state of Cd in soil, as well as inhibition of microbial activity, decreased with incubation time.

76 FR 17425 - Agency Information Collection Activities: Entry of Articles for Exhibition

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-29

... Activities: Entry of Articles for Exhibition AGENCY: U.S. Customs and Border Protection, Department of... of Articles for Exhibition (19 CFR 147.11(c)). This is a proposed extension of an information... other technological techniques or other forms of information. Title: Entry of Articles for Exhibition...

Ionospheric irregularities and acoustic/gravity wave activity above low-latitude thunderstorms

DOE PAGES

Lay, Erin H.

2017-12-18

Ionospheric irregularities due to plasma bubbles, scintillation, and acoustic/gravity waves are studied in the low-latitude ionosphere in relation to thunderstorm activity. Ionospheric total electron content (TEC) measurements from the Low Latitude Ionospheric Sensor Network (LISN) and lightning measurements from the World-Wide Lightning Location Network (WWLLN) are compared during two summer months and two winter months in 2013. Large amplitude fluctuations in TEC are found to have a strongly-peaked diurnal pattern in the late evening and nighttime summer ionosphere. The maximum magnitude and coverage area of these fluctuations increases as thunderstorm area increases. Summertime mid-amplitude fluctuations do not exhibit the samemore » diurnal variation, but do increase in magnitude and coverage area as thunderstorm area increases. Wintertime ionospheric fluctuations do not appear to be related to thunderstorm activity. Lastly, these findings show that thunderstorms have an observable effect on magnitude and coverage area of ionospheric fluctuations.« less

Ionospheric irregularities and acoustic/gravity wave activity above low-latitude thunderstorms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lay, Erin H.

Ionospheric irregularities due to plasma bubbles, scintillation, and acoustic/gravity waves are studied in the low-latitude ionosphere in relation to thunderstorm activity. Ionospheric total electron content (TEC) measurements from the Low Latitude Ionospheric Sensor Network (LISN) and lightning measurements from the World-Wide Lightning Location Network (WWLLN) are compared during two summer months and two winter months in 2013. Large amplitude fluctuations in TEC are found to have a strongly-peaked diurnal pattern in the late evening and nighttime summer ionosphere. The maximum magnitude and coverage area of these fluctuations increases as thunderstorm area increases. Summertime mid-amplitude fluctuations do not exhibit the samemore » diurnal variation, but do increase in magnitude and coverage area as thunderstorm area increases. Wintertime ionospheric fluctuations do not appear to be related to thunderstorm activity. Lastly, these findings show that thunderstorms have an observable effect on magnitude and coverage area of ionospheric fluctuations.« less

Ionospheric Irregularities and Acoustic/Gravity Wave Activity Above Low-Latitude Thunderstorms

NASA Astrophysics Data System (ADS)

Lay, Erin H.

2018-01-01

Ionospheric irregularities due to plasma bubbles, scintillation, and acoustic/gravity waves are studied in the low-latitude ionosphere in relation to thunderstorm activity. Ionospheric total electron content (TEC) measurements from the Low Latitude Ionospheric Sensor Network and lightning measurements from the World-Wide Lightning Location Network are compared during two summer months and two winter months in 2013. Large amplitude fluctuations in TEC are found to have a strongly peaked diurnal pattern in the late evening and nighttime summer ionosphere. The maximum magnitude and coverage area of these fluctuations increases as thunderstorm area increases. Summertime midamplitude fluctuations do not exhibit the same diurnal variation but do increase in magnitude and coverage area as thunderstorm area increases. Wintertime ionospheric fluctuations do not appear to be related to thunderstorm activity. These findings show that thunderstorms have an observable effect on magnitude and coverage area of ionospheric fluctuations.

The influence of duckweed species diversity on ecophysiological tolerance to copper exposure.

PubMed

Zhao, Zhao; Shi, Huijuan; Duan, Dongzhu; Li, Hongmei; Lei, Tingwen; Wang, Maolin; Zhao, Hai; Zhao, Yun

2015-07-01

In excess, copper is toxic to plants. In the plants, Landoltia punctata and Lemna minor grown in mixed and monoculture, the effects of exposure to varying concentrations of copper (0.01, 0.1, 0.5 and 1mgL(-1) Cu) for seven days were assessed by measuring changes in the chlorophyll, protein and malondialdehyde (MDA) content, catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity. According to results, Cu levels in plants increased with increasing Cu concentration. The level of photosynthetic pigments and crude proteins decreased only upon exposure to high Cu concentrations. However, the starch and malondialdehyde (MDA) content increased. These results suggested a stress alleviation that was possibly the result of antioxidants such as CAT and SOD, the activities of which increased with increasing Cu levels. APX activity increased in L. punctata, but decreased in L. minor, under monoculture or mixed culture conditions. In addition, the duckweed in mixed culture exhibited increased antioxidant enzyme activities which provide increased resistance to copper in moderate copper concentrations. As the copper concentration increased, the duckweed in the mixed culture limited the uptake of copper to avoid toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

Benomyl-resistant mutant strain of Trichoderma sp. with increased mycoparasitic activity.

PubMed

Olejníková, P; Ondrusová, Z; Krystofová, S; Hudecová, D

2010-01-01

Application of UV radiation to the strain Trichoderma sp. T-bt (isolated from lignite) resulted in the T-brm mutant which was resistant to the systemic fungicide benomyl. The tub2 gene sequence in the T-brm mutant differed from the parent as well as the collection strain (replacing tyrosine with histidine in the TUB2 protein). Under in vitro conditions this mutant exhibited a higher mycoparasitic activity toward phytopathogenic fungi.

Development of Burdock Root Inulin/Chitosan Blend Films Containing Oregano and Thyme Essential Oils.

PubMed

Cao, Thi Luyen; Yang, So-Young; Song, Kyung Bin

2018-01-03

In this study, inulin (INU) extracted from burdock root was utilized as a new film base material and combined with chitosan (CHI) to prepare composite films. Oregano and thyme essential oils (OT) were incorporated into the INU-CHI film to confer the films with bioactivities. The physical and optical properties as well as antioxidant and antimicrobial activities of the films were evaluated. INU film alone showed poor physical properties. In contrast, the compatibility of INU and CHI demonstrated by the changes in attenuated total reflectance-Fourier transformation infrared spectrum of the INU-CHI film increased tensile strength and elongation at break of the INU film by 8.2- and 3.9-fold, respectively. In addition, water vapor permeability, water solubility, and moisture content of the films decreased proportionally with increasing OT concentration in the INU-CHI film. Incorporation of OT also increased the opacity of a and b values and decreased the L value of the INU-CHI films. All INU-CHI films containing OT exhibited antioxidant and antimicrobial properties. Particularly, the INU-CHI film with 2.0% OT exhibited the highest 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), 2,2-diphenyl-1-picrylhydrazyl radical scavenging, and antimicrobial activities against four pathogens. Thus, the INU-CHI film containing OT developed in this study might be utilized as an active packaging material in the food industry.

Development of Burdock Root Inulin/Chitosan Blend Films Containing Oregano and Thyme Essential Oils

PubMed Central

Cao, Thi Luyen; Yang, So-Young; Song, Kyung Bin

2018-01-01

In this study, inulin (INU) extracted from burdock root was utilized as a new film base material and combined with chitosan (CHI) to prepare composite films. Oregano and thyme essential oils (OT) were incorporated into the INU-CHI film to confer the films with bioactivities. The physical and optical properties as well as antioxidant and antimicrobial activities of the films were evaluated. INU film alone showed poor physical properties. In contrast, the compatibility of INU and CHI demonstrated by the changes in attenuated total reflectance-Fourier transformation infrared spectrum of the INU-CHI film increased tensile strength and elongation at break of the INU film by 8.2- and 3.9-fold, respectively. In addition, water vapor permeability, water solubility, and moisture content of the films decreased proportionally with increasing OT concentration in the INU-CHI film. Incorporation of OT also increased the opacity of a and b values and decreased the L value of the INU-CHI films. All INU-CHI films containing OT exhibited antioxidant and antimicrobial properties. Particularly, the INU-CHI film with 2.0% OT exhibited the highest 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), 2,2-diphenyl-1-picrylhydrazyl radical scavenging, and antimicrobial activities against four pathogens. Thus, the INU-CHI film containing OT developed in this study might be utilized as an active packaging material in the food industry. PMID:29301339

Solvent exchange-induced in situ forming gel comprising ethyl cellulose-antimicrobial drugs.

PubMed

Phaechamud, Thawatchai; Mahadlek, Jongjan

2015-10-15

Solvent-exchanged in situ forming gel is a drug delivery system which is in sol form before administration. When it contacts with the body fluid, then the water miscible organic solvent dissipates and water penetrates into the system, leading the polymer precipitation as in situ gel at the site of injection. The aim of this research was to study the parameters affecting the gel properties, drug release and antimicrobial activities of the in situ forming gels prepared from ethyl cellulose (EC) dissolved in N-methyl pyrrolidone (NMP) to deliver the antimicrobial agents (doxycycline hyclate, metronidazole and benzyl peroxide) for periodontitis treatment. The gel appearance, pH, viscosity, rheology, syringeability, gel formation, rate of water diffusion into the gels, in vitro degradation, drug release behavior and antimicrobial activities against Staphylococcus aureus, Escherichia coli, Candida albicans, Streptococcus mutans and Porphyrommonas gingivalis were determined. Increasing the amount of EC increased the viscosity of system while still exhibiting Newtonian flow and increased the work of syringeability whereas decreased the releasing of drug. The system transformed into the rigid gel formation after being injected into the simulated gingival crevicular fluid. The developed systems containing 5% w/w antimicrobial agent showed the antimicrobial activities against all test bacteria. Thus the developed solvent exchange-induced in situ forming gels comprising EC-antimicrobial drugs exhibited potential use for periodontitis treatment. Copyright © 2015 Elsevier B.V. All rights reserved.

Context Memory Decline in Middle Aged Adults is Related to Changes in Prefrontal Cortex Function

PubMed Central

Kwon, Diana; Maillet, David; Pasvanis, Stamatoula; Ankudowich, Elizabeth; Grady, Cheryl L.; Rajah, M. Natasha

2016-01-01

The ability to encode and retrieve spatial and temporal contextual details of episodic memories (context memory) begins to decline at midlife. In the current study, event-related fMRI was used to investigate the neural correlates of context memory decline in healthy middle aged adults (MA) compared with young adults (YA). Participants were scanned while performing easy and hard versions of spatial and temporal context memory tasks. Scans were obtained at encoding and retrieval. Significant reductions in context memory retrieval accuracy were observed in MA, compared with YA. The fMRI results revealed that overall, both groups exhibited similar patterns of brain activity in parahippocampal cortex, ventral occipito-temporal regions and prefrontal cortex (PFC) during encoding. In contrast, at retrieval, there were group differences in ventral occipito-temporal and PFC activity, due to these regions being more activated in MA, compared with YA. Furthermore, only in YA, increased encoding activity in ventrolateral PFC, and increased retrieval activity in occipital cortex, predicted increased retrieval accuracy. In MA, increased retrieval activity in anterior PFC predicted increased retrieval accuracy. These results suggest that there are changes in PFC contributions to context memory at midlife. PMID:25882039

Effects of changes in vertical occlusal dimension on heart rate fluctuations in guinea pigs.

PubMed

Taga, Hitoshi; Azuma, Yukio; Maehara, Kiyoshi; Nomura, Shuichi

2012-01-01

We have previously reported that the decrease of the vertical occlusal dimension (VOD) led to heart failure and abnormalities in creatine phosphokinase (CPK) in guinea pigs. In the present study, we investigated the autonomic activity and the origin of the abnormality in CPK under different occlusal conditions. Guinea pigs were separated into the following five groups: untreated control, reduced VOD, slit, restored VOD and increased VOD groups and compared for their electrocardiogram and heart rate fluctuations for two weeks using Fluclet, computer software. The control group revealed no changes in heart rate fluctuations or posture. The reduced VOD group exhibited a two-phase wave of heart rate fluctuations, with the first peak 0-2 days after teeth grinding, and the second peak starting from 4 days after teeth grinding until sudden death (usually 12th day), accompanied by head drop. The slit and the restored VOD groups exhibited only the first peak. The increased VOD group, with approximately 3 mm-thick acrylic pellets bonded to the posterior teeth, showed no heart rate fluctuations. Body weight loss was most prominent in the reduced VOD group, and became much milder in the order of increased VOD, restored and slit groups. The reduced VOD group exhibited transient elevation of skeletal muscle type of CPK isozyme activity within two days after treatment. The present study suggests that the first peak of heart rate fluctuations is caused by pulpal stimulation, and the second peak by excessive contraction (excessive excitation of the motor output system and the autonomic nervous system) of the masticatory muscles. On the other hand, increased VOD did not influence either the motor or the autonomic nervous system.

High Boron-loaded DNA-Oligomers as Potential Boron Neutron Capture Therapy and Antisense Oligonucleotide Dual-Action Anticancer Agents.

PubMed

Kaniowski, Damian; Ebenryter-Olbińska, Katarzyna; Sobczak, Milena; Wojtczak, Błażej; Janczak, Sławomir; Leśnikowski, Zbigniew J; Nawrot, Barbara

2017-08-23

Boron cluster-modified therapeutic nucleic acids with improved properties are of interest in gene therapy and in cancer boron neutron capture therapy (BNCT). High metallacarborane-loaded antisense oligonucleotides (ASOs) targeting epidermal growth factor receptor (EGFR) were synthesized through post-synthetic Cu (I)-assisted "click" conjugation of alkyne-modified DNA-oligonucleotides with a boron cluster alkyl azide component. The obtained oligomers exhibited increased lipophilicity compared to their non-modified precursors, while their binding affinity to complementary DNA and RNA strands was slightly decreased. Multiple metallacarborane residues present in the oligonucleotide chain, each containing 18 B-H groups, enabled the use of IR spectroscopy as a convenient analytical method for these oligomers based on the diagnostic B-H signal at 2400-2650 cm -1 . The silencing activity of boron cluster-modified ASOs used at higher concentrations was similar to that of unmodified oligonucleotides. The screened ASOs, when used in low concentrations (up to 50 μM), exhibited pro-oxidative properties by inducing ROS production and an increase in mitochondrial activities in HeLa cells. In contrast, when used at higher concentrations, the ASOs exhibited anti-oxidative properties by lowering ROS species levels. In the HeLa cells (tested in the MTT assay) treated (without lipofectamine) or transfected with the screened compounds, the mitochondrial activity remained equal to the control level or only slightly changed (±30%). These findings may be useful in the design of dual-action boron cluster-modified therapeutic nucleic acids with combined antisense and anti-oxidant properties.

The role of gibberellins in improving the resistance of tebuconazole-coated maize seeds to chilling stress by microencapsulation

NASA Astrophysics Data System (ADS)

Yang, Lijuan; Yang, Daibin; Yan, Xiaojing; Cui, Li; Wang, Zhenying; Yuan, Huizhu

2016-11-01

Chilling stress during germination often causes severe injury. In the present study, maize seed germination and shoot growth under chilling stress were negatively correlated with the dose of tebuconazole in an exponential manner as predicted by the model Y = A + B × e(-x/k). Microencapsulation was an effective means of eliminating potential phytotoxic risk. The gibberellins (GAs) contents were higher after microencapsulation treatment than after conventional treatment when the dose of tebuconazole was higher than 0.12 g AI (active ingredient) kg-1 seed. Further analysis indicated that microencapsulation can stimulate ent-kaurene oxidase (KO) activity to some extent, whereas GA 3-oxidase (GA3ox) and GA 2-oxidase (GA2ox) activities remained similar to those in the control. Genes encoding GA metabolic enzymes exhibited different expression patterns. Transcript levels of ZmKO1 increased in the microcapsule treatments compared to the control. Even when incorporated into microcapsules, tebuconazole led to the upregulation of ZmGA3ox1 at doses of less than 0.12 g AI kg-1 seed and to the upregulation of ZmGA3ox2 when the dose was higher than 0.12 g AI kg-1 seed. With increasing doses of microencapsulated tebuconazole, the transcript levels of ZmGA2ox4, ZmGA2ox5 and ZmGA2ox6 exhibited upward trends, whereas the transcript levels of ZmGA2ox7 exhibited a downward trend.

Compassionate Love Buffers Stress-Reactive Mothers From Fight-or-Flight Parenting

PubMed Central

Miller, Jonas G.; Kahle, Sarah; Lopez, Monica; Hastings, Paul D.

2015-01-01

The links among mothers’ compassionate love for their child, autonomic nervous system activity, and parenting behavior during less and more challenging mother–child interactions were examined. Mothers expressed and reported less negative affect when they exhibited autonomic patterns of increased parasympathetic dominance (high parasympathetic and low sympathetic activation) or autonomic coactivation (high parasympathetic and high sympathetic activation) during the less challenging interaction and autonomic coactivation during the more challenging interaction. Compassionate love predicted less reported and observed negativity in mothers who showed increased sympathetic nervous system dominance (high sympathetic and low parasympathetic activation). Compassionate love appeared to help mothers, and particularly those who experienced strong physiological arousal during difficult parenting situations, establish positive socialization contexts for their children and avoid stress-induced adverse parenting. PMID:25329554

Defective calcium inactivation causes long QT in obese insulin-resistant rat.

PubMed

Lin, Yen-Chang; Huang, Jianying; Kan, Hong; Castranova, Vincent; Frisbee, Jefferson C; Yu, Han-Gang

2012-02-15

The majority of diabetic patients who are overweight or obese die of heart disease. We suspect that the obesity-induced insulin resistance may lead to abnormal cardiac electrophysiology. We tested this hypothesis by studying an obese insulin-resistant rat model, the obese Zucker rat (OZR). Compared with the age-matched control, lean Zucker rat (LZR), OZR of 16-17 wk old exhibited an increase in QTc interval, action potential duration, and cell capacitance. Furthermore, the L-type calcium current (I(CaL)) in OZR exhibited defective inactivation and lost the complete inactivation back to the closed state, leading to increased Ca(2+) influx. The current density of I(CaL) was reduced in OZR, whereas the threshold activation and the current-voltage relationship of I(CaL) were not significantly altered. L-type Ba(2+) current (I(BaL)) in OZR also exhibited defective inactivation, and steady-state inactivation was not significantly altered. However, the current-voltage relationship and activation threshold of I(BaL) in OZR exhibited a depolarized shift compared with LZR. The total and membrane protein expression levels of Cav1.2 [pore-forming subunit of L-type calcium channels (LTCC)], but not the insulin receptors, were decreased in OZR. The insulin receptor was found to be associated with the Cav1.2, which was weakened in OZR. The total protein expression of calmodulin was reduced, but that of Cavβ2 subunit was not altered in OZR. Together, these results suggested that the 16- to 17-wk-old OZR has 1) developed cardiac hypertrophy, 2) exhibited altered electrophysiology manifested by the prolonged QTc interval, 3) increased duration of action potential in isolated ventricular myocytes, 4) defective inactivation of I(CaL) and I(BaL), 5) weakened the association of LTCC with the insulin receptor, and 6) decreased protein expression of Cav1.2 and calmodulin. These results also provided mechanistic insights into a remodeled cardiac electrophysiology under the condition of insulin resistance, enhancing our understanding of long QT associated with obese type 2 diabetic patients.

Zebrafish aussicht mutant embryos exhibit widespread overexpression of ace (fgf8) and coincident defects in CNS development.

PubMed

Heisenberg, C P; Brennan, C; Wilson, S W

1999-05-01

During the development of the zebrafish nervous system both noi, a zebrafish pax2 homolog, and ace, a zebrafish fgf8 homolog, are required for development of the midbrain and cerebellum. Here we describe a dominant mutation, aussicht (aus), in which the expression of noi and ace is upregulated. In aus mutant embryos, ace is upregulated at many sites in the embryo, while noi expression is only upregulated in regions of the forebrain and midbrain which also express ace. Subsequent to the alterations in noi and ace expression, aus mutants exhibit defects in the differentiation of the forebrain, midbrain and eyes. Within the forebrain, the formation of the anterior and postoptic commissures is delayed and the expression of markers within the pretectal area is reduced. Within the midbrain, En and wnt1 expression is expanded. In heterozygous aus embryos, there is ectopic outgrowth of neural retina in the temporal half of the eyes, whereas in putative homozygous aus embryos, the ventral retina is reduced and the pigmented retinal epithelium is expanded towards the midline. The observation that aus mutant embryos exhibit widespread upregulation of ace raised the possibility that aus might represent an allele of the ace gene itself. However, by crossing carriers for both aus and ace, we were able to generate homozygous ace mutant embryos that also exhibited the aus phenotype. This indicated that aus is not tightly linked to ace and is unlikely to be a mutation directly affecting the ace locus. However, increased Ace activity may underly many aspects of the aus phenotype and we show that the upregulation of noi in the forebrain of aus mutants is partially dependent upon functional Ace activity. Conversely, increased ace expression in the forebrain of aus mutants is not dependent upon functional Noi activity. We conclude that aus represents a mutation involving a locus normally required for the regulation of ace expression during embryogenesis.

Effect of nitric acid treatment on activated carbon derived from oil palm shell

NASA Astrophysics Data System (ADS)

Allwar, Allwar; Hartati, Retno; Fatimah, Is

2017-03-01

The primary object of this work is to study the effect of nitric acid on the porous and morphology structure of activated carbon. Production of activated carbon from oil palm shell was prepared with pyrolysis process at temperature 900°C and by introduction of 10 M nitric acid. Determination of surface area, pore volume and pore size distribution of activated carbon was conducted by the N2 adsorption-desorption isotherm at 77 K. Morphology structure and elemental micro-analysis of activated carbon were estimated by Scanning Electron Microscopy (SEM) and energy dispersive X-ray (EDX), respectively. The result shows that activated carbon after treating with nitric acid proved an increasing porous characteristics involving surface area, pore volume and pore size distribution. It also could remove the contaminants including metals and exhibit an increasing of pores and crevices all over the surface.

Oxidative stress upregulates zinc uptake activity via Zrt/Irt-like protein 1 (ZIP1) in cultured mouse astrocytes.

PubMed

Furuta, Takahiro; Ohshima, Chiaki; Matsumura, Mayu; Takebayashi, Naoto; Hirota, Emi; Mawaribuchi, Toshiki; Nishida, Kentaro; Nagasawa, Kazuki

2016-04-15

Zinc released from glutamatergic boutons and astrocytes acts as neuro- and glio-transmitters, and thus its extracellular level has to be strictly regulated. We previously revealed that uptake of zinc by astrocytes plays a critical role in its clearance, and zinc transporter Zrt/Irt-like protein 1 (ZIP1) is the molecule responsible for the uptake. However, it is unknown whether or not the functionality of the zinc clearance system is altered under oxidative stress-loaded conditions. Here, we characterized zinc uptake by oxidative stress-loaded astrocytes. Cultured mouse astrocytes were treated with hydrogen peroxide (H2O2) to load oxidative stress. Functional expression of ZIP1 in astrocytes was evaluated by means of (65)Zn uptake, Western blotting and immunocytochemical analysis. Treatment of astrocytes with 0.4mM H2O2 for 24h increased the expression levels of glial fibrillary acidic protein and 4-hydroxynonenal without significant decreases in their viability, indicating that induction of oxidative stress in astrocytes. Under oxidative stress-loaded conditions, astrocytes exhibited increased (65)Zn uptake activity, and the maximum uptake velocity for the uptake was significantly increased compared to that in the control group, while there was no change in the Michaelis constants, which were almost identical to that of mouse ZIP1. In the H2O2-treated astrocytes, the expression levels of ZIP1 were significantly increased in the cellular and plasma membrane fractions. It appears that under oxidative stress-loaded conditions, astrocytes exhibit increased zinc clearance activity and this is due, at least in part, to increased ZIP1 expression. Copyright © 2016 Elsevier Inc. All rights reserved.

Comprehensive behavioral analysis of pituitary adenylate cyclase-activating polypeptide (PACAP) knockout mice

PubMed Central

Hattori, Satoko; Takao, Keizo; Tanda, Koichi; Toyama, Keiko; Shintani, Norihito; Baba, Akemichi; Hashimoto, Hitoshi; Miyakawa, Tsuyoshi

2012-01-01

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide acting as a neurotransmitter, neuromodulator, or neurotrophic factor. PACAP is widely expressed throughout the brain and exerts its functions through the PACAP-specific receptor (PAC1). Recent studies reveal that genetic variants of the PACAP and PAC1 genes are associated with mental disorders, and several behavioral abnormalities of PACAP knockout (KO) mice are reported. However, an insufficient number of backcrosses was made using PACAP KO mice on the C57BL/6J background due to their postnatal mortality. To elucidate the effects of PACAP on neuropsychiatric function, the PACAP gene was knocked out in F1 hybrid mice (C57BL/6J × 129SvEv) for appropriate control of the genetic background. The PACAP KO mice were then subjected to a behavioral test battery. PACAP deficiency had no significant effects on neurological screen. As shown previously, the mice exhibited significantly increased locomotor activity in a novel environment and abnormal anxiety-like behavior, while no obvious differences between genotypes were shown in home cage (HC) activity. In contrast to previous reports, the PACAP KO mice showed normal prepulse inhibition (PPI) and slightly decreased depression-like behavior. Previous study demonstrates that the social interaction (SI) in a resident-intruder test was decreased in PACAP KO mice. On the other hand, we showed that PACAP KO mice exhibited increased SI in Crawley's three-chamber social approach test, although PACAP KO had no significant impact on SI in a HC. PACAP KO mice also exhibited mild performance deficit in working memory in an eight-arm radial maze (RM) and the T-maze (TM), while they did not show any significant abnormalities in the left-right discrimination task in the TM. These results suggest that PACAP has an important role in the regulation of locomotor activity, social behavior, anxiety-like behavior and, potentially, working memory. PMID:23060763

Decreased medial prefrontal cortex activation during self-referential processing in bipolar mania.

PubMed

Herold, Dorrit; Usnich, Tatiana; Spengler, Stephanie; Sajonz, Bastian; Bauer, Michael; Bermpohl, Felix

2017-09-01

Patients with bipolar disorder in mania exhibit symptoms pointing towards altered self-referential processing, such as decreased self-focus, flight of ideas and high distractibility. In depression, the opposite pattern of symptoms has been connected to increased activation of medial prefrontal cortex (mPFC) during self-referential processing. In this study, we hypothesized that (1) patients with mania will exhibit decreased activation in the mPFC during self-referential processing and (2) will be more alexithymic and that levels of alexithymia will correlate negatively with mPFC activation. The neural response to standardized pictures was compared in 14 patients with bipolar I disorder in mania to 14 healthy controls using blood oxygen level dependent contrast magnetic resonance imaging. Participants were asked to indicate with button press during the scanning session for each picture whether the pictures personally related to them or not. Toronto alexithymia scale (TAS) scores were recorded from all participants. In the group analysis, patients with mania exhibited decreased activation in a predefined region of interest in the mPFC during self-referential processing compared to healthy controls. Patients with mania showed significantly higher levels of alexithymia, attributable to difficulties in identifying and describing emotions. Activation in the mPFC correlated negatively with levels of alexithymia. Results presented here should be replicated in a larger group, potentially including unmedicated patients. The finding of decreased mPFC activation during self-referential processing in mania may reflect decreased self-focus and high distractibility. Support for this view comes from the negative correlation between higher alexithymia scores and decreased mPFC activation. These findings represent an opposite clinical and neuroimaging pattern to findings in depression. Copyright © 2017. Published by Elsevier B.V.

Palladium and Platinum Nanoparticles Attenuate Aging-Like Skin Atrophy via Antioxidant Activity in Mice

PubMed Central

Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

2014-01-01

Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1 −/− mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1 −/− mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage. PMID:25333617

Palladium and platinum nanoparticles attenuate aging-like skin atrophy via antioxidant activity in mice.

PubMed

Shibuya, Shuichi; Ozawa, Yusuke; Watanabe, Kenji; Izuo, Naotaka; Toda, Toshihiko; Yokote, Koutaro; Shimizu, Takahiko

2014-01-01

Cu-Zn superoxide dismutase (Sod1) loss causes a redox imbalance as it leads to excess superoxide generation, which results in the appearance of various aging-related phenotypes, including skin atrophy. Noble metal nanoparticles, such as palladium (Pd) and platinum (Pt) nanoparticles, are considered to function as antioxidants due to their strong catalytic activity. In Japan, a mixture of Pd and Pt nanoparticles called PAPLAL has been used to treat chronic diseases over the past 60 years. In the present study, we investigated the protective effects of PAPLAL against aging-related skin pathologies in mice. Transdermal PAPLAL treatment reversed skin thinning associated with increased lipid peroxidation in Sod1-/- mice. Furthermore, PAPLAL normalized the gene expression levels of Col1a1, Mmp2, Has2, Tnf-α, Il-6, and p53 in the skin of the Sod1-/- mice. Pt nanoparticles exhibited marked SOD and catalase activity, while Pd nanoparticles only displayed weak SOD and catalase activity in vitro. Although the SOD and catalase activity of the Pt nanoparticles significantly declined after they had been oxidized in air, a mixture of Pd and Pt nanoparticles continued to exhibit SOD and catalase activity after oxidation. Importantly, a mixture of Pd and Pt nanoparticles with a molar ratio of 3 or 4 to 1 continued to exhibit SOD and catalase activity after oxidation, indicating that Pd nanoparticles prevent the oxidative deterioration of Pt nanoparticles. These findings indicate that PAPLAL stably suppresses intrinsic superoxide generation both in vivo and in vitro via SOD and catalase activity. PAPLAL is a potentially powerful tool for the treatment of aging-related skin diseases caused by oxidative damage.

[Determination of the healing effect of Piper aduncum (spiked pepper or matico) on human fibroblasts].

PubMed

Paco, Karen; Ponce-Soto, Luis Alberto; Lopez-Ilasaca, Marco; Aguilar, José L

2016-01-01

To evaluate the healing effect of a Piper aduncum ethanol-water extract on an adult human dermal fibroblast cell line (hDFa). After obtaining the extract via solid-liquid extraction, concentration, and lyophilization, extract proteins were purified using reverse phase high-performance liquid chromatography, identified using tandem mass spectrometry of tryptic peptides, and analyzed using MALDI-TOF-TOF on an ABSciex4800 mass spectrometer. Half maximum effective concentration values (EC50), half maximum inhibiting concentration (IC50), and percentages of cell proliferation were determined using tetrazolium salt assays. Cell migration was evaluated using a "scratch assay". Growth factor expression in cells was analyzed via quantitative real-time reverse transcription polymerase chain reaction. Against the hDFa cell line, the extract had an IC50 of 200 μg/mL and EC50 of 103.5 µg/mL. In the proliferation assay, protein K2 (obtained from the extract) exhibited increased proliferative activity relative to other treatments (1 µg/mL); this agent also exhibited increased activity (50 µg/mL) in the fibroblast migration assay.Furthermore, the relative expression of platelet-derived growth factor increased by 8.6-fold in the presence of K2 protein relative to the control. The hydroethanolic extract of Piper aduncum and its component proteins increased the proliferation and migration of hDFa and increased the expression of growth factors involved in the healing process.

Ecological allometries and niche use dynamics across Komodo dragon ontogeny.

PubMed

Purwandana, Deni; Ariefiandy, Achmad; Imansyah, M Jeri; Seno, Aganto; Ciofi, Claudio; Letnic, Mike; Jessop, Tim S

2016-04-01

Ontogenetic allometries in ecological habits and niche use are key responses by which individuals maximize lifetime fitness. Moreover, such allometries have significant implications for how individuals influence population and community dynamics. Here, we examined how body size variation in Komodo dragons (Varanus komodoensis) influenced ecological allometries in their: (1) prey size preference, (2) daily movement rates, (3) home range area, and (4) subsequent niche use across ontogeny. With increased body mass, Komodo dragons increased prey size with a dramatic switch from small (≤10 kg) to large prey (≥50 kg) in lizards heavier than 20 kg. Rates of foraging movement were described by a non-linear concave down response with lizard increasing hourly movement rates up until ∼20 kg body mass before decreasing daily movement suggesting reduced foraging effort in larger lizards. In contrast, home range area exhibited a sigmoid response with increased body mass. Intrapopulation ecological niche use and overlap were also strongly structured by body size. Thus, ontogenetic allometries suggest Komodo dragon's transition from a highly active foraging mode exploiting small prey through to a less active sit and wait feeding strategy focused on killing large ungulates. Further, our results suggest that as body size increases across ontogeny, the Komodo dragon exhibited marked ontogenetic niche shifts that enabled it to function as an entire vertebrate predator guild by exploiting prey across multiple trophic levels.

Ecological allometries and niche use dynamics across Komodo dragon ontogeny

NASA Astrophysics Data System (ADS)

Purwandana, Deni; Ariefiandy, Achmad; Imansyah, M. Jeri; Seno, Aganto; Ciofi, Claudio; Letnic, Mike; Jessop, Tim S.

2016-04-01

Ontogenetic allometries in ecological habits and niche use are key responses by which individuals maximize lifetime fitness. Moreover, such allometries have significant implications for how individuals influence population and community dynamics. Here, we examined how body size variation in Komodo dragons ( Varanus komodoensis) influenced ecological allometries in their: (1) prey size preference, (2) daily movement rates, (3) home range area, and (4) subsequent niche use across ontogeny. With increased body mass, Komodo dragons increased prey size with a dramatic switch from small (≤10 kg) to large prey (≥50 kg) in lizards heavier than 20 kg. Rates of foraging movement were described by a non-linear concave down response with lizard increasing hourly movement rates up until ˜20 kg body mass before decreasing daily movement suggesting reduced foraging effort in larger lizards. In contrast, home range area exhibited a sigmoid response with increased body mass. Intrapopulation ecological niche use and overlap were also strongly structured by body size. Thus, ontogenetic allometries suggest Komodo dragon's transition from a highly active foraging mode exploiting small prey through to a less active sit and wait feeding strategy focused on killing large ungulates. Further, our results suggest that as body size increases across ontogeny, the Komodo dragon exhibited marked ontogenetic niche shifts that enabled it to function as an entire vertebrate predator guild by exploiting prey across multiple trophic levels.

Diffusion of GPI-anchored proteins is influenced by the activity of dynamic cortical actin

PubMed Central

Saha, Suvrajit; Lee, Il-Hyung; Polley, Anirban; Groves, Jay T.; Rao, Madan; Mayor, Satyajit

2015-01-01

Molecular diffusion at the surface of living cells is believed to be predominantly driven by thermal kicks. However, there is growing evidence that certain cell surface molecules are driven by the fluctuating dynamics of cortical cytoskeleton. Using fluorescence correlation spectroscopy, we measure the diffusion coefficient of a variety of cell surface molecules over a temperature range of 24–37°C. Exogenously incorporated fluorescent lipids with short acyl chains exhibit the expected increase of diffusion coefficient over this temperature range. In contrast, we find that GPI-anchored proteins exhibit temperature-independent diffusion over this range and revert to temperature-dependent diffusion on cell membrane blebs, in cells depleted of cholesterol, and upon acute perturbation of actin dynamics and myosin activity. A model transmembrane protein with a cytosolic actin-binding domain also exhibits the temperature-independent behavior, directly implicating the role of cortical actin. We show that diffusion of GPI-anchored proteins also becomes temperature dependent when the filamentous dynamic actin nucleator formin is inhibited. However, changes in cortical actin mesh size or perturbation of branched actin nucleator Arp2/3 do not affect this behavior. Thus cell surface diffusion of GPI-anchored proteins and transmembrane proteins that associate with actin is driven by active fluctuations of dynamic cortical actin filaments in addition to thermal fluctuations, consistent with expectations from an “active actin-membrane composite” cell surface. PMID:26378258

Synthesis and hypoglycemic activity of 9-O-(lipophilic group substituted) berberine derivatives.

PubMed

Zhang, Shanshan; Wang, Xiaohong; Yin, Weicheng; Liu, Zhenbao; Zhou, Mi; Xiao, Daipeng; Liu, Yanfei; Peng, Dongming

2016-10-01

A series of 9-O-(lipophilic group substituted) berberine derivatives were synthesized and evaluated for their cytotoxicity and hypoglycemic activity against HepG2 cells. All the results indicated that most of the synthesized compounds exhibited lower cytotoxicity and a certain degree of hypoglycemic activity. Especially the compounds 5g and 5h displayed dramatically increased hypoglycemic activity compared with berberine, and the cytotoxicity maintained or even lower than berberine, indicating that they are potential candidates for new anti-type 2 diabetes mellitus drugs. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transglutaminase activation in neurodegenerative diseases

PubMed Central

Jeitner, Thomas M; Muma, Nancy A; Battaile, Kevin P; Cooper, Arthur JL

2009-01-01

The following review examines the role of calcium in promoting the in vitro and in vivo activation of transglutaminases in neurodegenerative disorders. Diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease exhibit increased transglutaminase activity and rises in intracellular calcium concentrations, which may be related. The aberrant activation of transglutaminase by calcium is thought to give rise to a variety of pathological moieties in these diseases, and the inhibition has been shown to have therapeutic benefit in animal and cellular models of neurodegeneration. Given the potential clinical relevance of transglutaminase inhibitors, we have also reviewed the recent development of such compounds. PMID:20161049

Intrinsic viscosity and rheological properties of natural and substituted guar gums in seawater.

PubMed

Wang, Shibin; He, Le; Guo, Jianchun; Zhao, Jinzhou; Tang, Hongbiao

2015-05-01

The intrinsic viscosity and rheological properties of guar gum (GG), hydroxypropyl guar (HPG) and carboxymethyl guar (CMG) in seawater and the effects of shear rate, concentration, temperature and pH on these properties were investigated. An intrinsic viscosity-increasing effect was observed with GG and HPG in seawater (SW) compared to deionized water (DW), whereas the intrinsic viscosity of CMG in seawater was much lower than that in DW due to a screening effect that reduced the repulsion between the polymer chains. Regardless of the functional groups, all sample solutions was well characterized by a modified Cross model that exhibited the transition from Newtonian to pseudoplastic in the low shear rate range at the concentrations of interest to industries, and their viscosity increased with the increase in their concentration but decreased with the increase in temperature. In contrast to nonionic GG or HPG, anionic CMG had a slightly decreased viscosity property in SW, exhibiting polyelectrolyte viscosity behavior. The α value in the zero-shear rate viscosity vs. concentration power-law equation for the samples gave the order of CMG>HPG>GG while the SW solution of CMG had the lowest viscous flow activation energy and exhibited a strong pH-dependent viscosity by a different shear rate. Copyright © 2015 Elsevier B.V. All rights reserved.

Hippocampal place cell and inhibitory neuron activity in disrupted-in-schizophrenia-1 mutant mice: implications for working memory deficits

PubMed Central

Mesbah-Oskui, Lia; Georgiou, John; Roder, John C

2015-01-01

Background: Despite the prevalence of working memory deficits in schizophrenia, the neuronal mechanisms mediating these deficits are not fully understood. Importantly, deficits in spatial working memory are identified in numerous mouse models that exhibit schizophrenia-like endophenotypes. The hippocampus is one of the major brain regions that actively encodes spatial location, possessing pyramidal neurons, commonly referred to as ‘place cells’, that fire in a location-specific manner. This study tests the hypothesis that mice with a schizophrenia-like endophenotype exhibit impaired encoding of spatial location in the hippocampus. Aims: To characterize hippocampal place cell activity in mice that exhibit a schizophrenia-like endophenotype. Methods: We recorded CA1 place cell activity in six control mice and six mice that carry a point mutation in the disrupted-in-schizophrenia-1 gene (Disc1-L100P) and have previously been shown to exhibit deficits in spatial working memory. Results: The spatial specificity and stability of Disc1-L100P place cells were similar to wild-type place cells. Importantly, however, Disc1-L100P place cells exhibited a higher propensity to increase their firing rate in a single, large location of the environment, rather than multiple smaller locations, indicating a generalization in their spatial selectivity. Alterations in the signaling and numbers of CA1 putative inhibitory interneurons and decreased hippocampal theta (5–12 Hz) power were also identified in the Disc1-L100P mice. Conclusions: The generalized spatial selectivity of Disc1-L100P place cells suggests a simplification of the ensemble place codes that encode individual locations and subserve spatial working memory. Moreover, these results suggest that deficient working memory in schizophrenia results from an impaired ability to uniquely code the individual components of a memory sequence. PMID:27280123

76 FR 4929 - Agency Information Collection Activities: Entry of Articles for Exhibition.

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-27

... Activities: Entry of Articles for Exhibition. AGENCY: U.S. Customs and Border Protection (CBP), Department of... requirement concerning the Entry of Articles for Exhibition (19 CFR 147.11(c)). This request for comment is...: Title: Entry of Articles for Exhibition. OMB Number: 1651-0037. Form Number: None. Abstract: Goods...

Cholesterol-tethered platinum II-based supramolecular nanoparticle increases antitumor efficacy and reduces nephrotoxicity

PubMed Central

Sengupta, Poulomi; Basu, Sudipta; Soni, Shivani; Pandey, Ambarish; Roy, Bhaskar; Oh, Michael S.; Chin, Kenneth T.; Paraskar, Abhimanyu S.; Sarangi, Sasmit; Connor, Yamicia; Sabbisetti, Venkata S.; Kopparam, Jawahar; Kulkarni, Ashish; Muto, Katherine; Amarasiriwardena, Chitra; Jayawardene, Innocent; Lupoli, Nicola; Dinulescu, Daniela M.; Bonventre, Joseph V.; Mashelkar, Raghunath A.; Sengupta, Shiladitya

2012-01-01

Nanoscale drug delivery vehicles have been harnessed extensively as carriers for cancer chemotherapeutics. However, traditional pharmaceutical approaches for nanoformulation have been a challenge with molecules that exhibit incompatible physicochemical properties, such as platinum-based chemotherapeutics. Here we propose a paradigm based on rational design of active molecules that facilitate supramolecular assembly in the nanoscale dimension. Using cisplatin as a template, we describe the synthesis of a unique platinum (II) tethered to a cholesterol backbone via a unique monocarboxylato and O→Pt coordination environment that facilitates nanoparticle assembly with a fixed ratio of phosphatidylcholine and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino (polyethylene glycol)-2000]. The nanoparticles formed exhibit lower IC50 values compared with carboplatin or cisplatin in vitro, and are active in cisplatin-resistant conditions. Additionally, the nanoparticles exhibit significantly enhanced in vivo antitumor efficacy in murine 4T1 breast cancer and in K-RasLSL/+/Ptenfl/fl ovarian cancer models with decreased systemic- and nephro-toxicity. Our results indicate that integrating rational drug design and supramolecular nanochemistry can emerge as a powerful strategy for drug development. Furthermore, given that platinum-based chemotherapeutics form the frontline therapy for a broad range of cancers, the increased efficacy and toxicity profile indicate the constructed nanostructure could translate into a next-generation platinum-based agent in the clinics. PMID:22733767

Intraspecific protoplast fusion of Brettanomyces anomalus for improved production of an extracellular β-glucosidase.

PubMed

Wu, Peng; Zhao, Xihong; Pan, Siyi

2014-09-03

Improvement of production of an extracellular β-glucosidase with high activity by Brettanomyces anomalus PSY-001 was performed by using recursive protoplast fusion in a genome-shuffling format. The initial population was generated by ultraviolet irradiation, ultrasonic mutagenesis and, then, subjected to recursive protoplast fusion. Mutant strains exhibiting significantly higher β-glucosidase activities in liquid media were isolated. The best mutant strain showed increased cell growth in a flask culture, as well as increased β-glucosidase production. A recombinant strain, F3-25, was obtained after three rounds of genome shuffling and its production of β-glucosidase activity reached 4790 U L -1 , which was a nearly eightfold increase compared to the original strain B. anomalus PSY-001. The subculture experiments indicated that F3-25 was genetically stable.

Intraspecific protoplast fusion of Brettanomyces anomalus for improved production of an extracellular β-glucosidase

PubMed Central

Wu, Peng; Zhao, Xihong; Pan, Siyi

2014-01-01

Improvement of production of an extracellular β-glucosidase with high activity by Brettanomyces anomalus PSY-001 was performed by using recursive protoplast fusion in a genome-shuffling format. The initial population was generated by ultraviolet irradiation, ultrasonic mutagenesis and, then, subjected to recursive protoplast fusion. Mutant strains exhibiting significantly higher β-glucosidase activities in liquid media were isolated. The best mutant strain showed increased cell growth in a flask culture, as well as increased β-glucosidase production. A recombinant strain, F3-25, was obtained after three rounds of genome shuffling and its production of β-glucosidase activity reached 4790 U L−1, which was a nearly eightfold increase compared to the original strain B. anomalus PSY-001. The subculture experiments indicated that F3-25 was genetically stable. PMID:26019572

Mechanochemical activation and patterning of an adhesive surface toward nanoparticle deposition.

PubMed

Baytekin, H Tarik; Baytekin, Bilge; Huda, Sabil; Yavuz, Zelal; Grzybowski, Bartosz A

2015-02-11

Mechanical pulling of adhesive tape creates radicals on the tape's surface. These radicals are capable of reducing metal salts to the corresponding metal nanoparticles. In this way, the mechanically activated tape can be decorated with various types of nanoparticles, including Au, Ag, Pd, or Cu. While retaining their mechanical properties and remaining "sticky," the tapes can exhibit new properties derived from the presence of metal nanoparticles (e.g., bacteriostaticity, increased electrical conductivity). They can also be patterned with nanoparticles only at selective locations of mechanical activation.

Screening of some Greek aromatic plants for antioxidant activity.

PubMed

Couladis, Maria; Tzakou, Olga; Verykokidou, Evmorfia; Harvala, Catherine

2003-02-01

The role of antioxidants in preventing oxygen radical and hydrogen peroxide induced cytotoxicity and tissue damage in various human diseases is increasingly recognized. In this study the in vitro antioxidant activity of the ethanol extracts obtained from 21 aromatic plants belonging to the Lamiaceae family was investigated. Of the extracts tested, those of Salvia ringens, Salvia pomifera, Stachys spruneri, Origanum dictamnus, Phlomis lanata, Ballota pseudodictamnus, Ballota acetabulosa, Teucrium polium, Calamintha glandulosa and Micromeria graeca exhibited the same activity as alpha-tocopherol. Copyright 2003 John Wiley & Sons, Ltd.

Detection and description of non-linear interdependence in normal multichannel human EEG data.

PubMed

Breakspear, M; Terry, J R

2002-05-01

This study examines human scalp electroencephalographic (EEG) data for evidence of non-linear interdependence between posterior channels. The spectral and phase properties of those epochs of EEG exhibiting non-linear interdependence are studied. Scalp EEG data was collected from 40 healthy subjects. A technique for the detection of non-linear interdependence was applied to 2.048 s segments of posterior bipolar electrode data. Amplitude-adjusted phase-randomized surrogate data was used to statistically determine which EEG epochs exhibited non-linear interdependence. Statistically significant evidence of non-linear interactions were evident in 2.9% (eyes open) to 4.8% (eyes closed) of the epochs. In the eyes-open recordings, these epochs exhibited a peak in the spectral and cross-spectral density functions at about 10 Hz. Two types of EEG epochs are evident in the eyes-closed recordings; one type exhibits a peak in the spectral density and cross-spectrum at 8 Hz. The other type has increased spectral and cross-spectral power across faster frequencies. Epochs identified as exhibiting non-linear interdependence display a tendency towards phase interdependencies across and between a broad range of frequencies. Non-linear interdependence is detectable in a small number of multichannel EEG epochs, and makes a contribution to the alpha rhythm. Non-linear interdependence produces spatially distributed activity that exhibits phase synchronization between oscillations present at different frequencies. The possible physiological significance of these findings are discussed with reference to the dynamical properties of neural systems and the role of synchronous activity in the neocortex.

Strain improvement of Aspergillus niger for enhanced lipase production.

PubMed

Sandana Mala, John Geraldine; Kamini, Numbi R.; Puvanakrishnan, Rengarajulu

2001-08-01

The enhancement of lipase production from Aspergillus niger was attempted by ultraviolet (UV) and nitrous acid mutagenesis, and the mutants were selected on media containing bile salts. Nitrous acid mutants exhibited increased efficiency for lipase production when compared with UV mutants in submerged fermentation. The hyperproducing UV and nitrous acid mutants were further subjected to a second step of mutagenesis to devise an economical and ecofriendly technique for lipase production by the effective use of hydrocarbons. One percent kerosene was found to be optimal for lipase production, and one of the mutant strains NAII exhibited 2.53 times more increased lipase activity than the parental strain did. This investigation indicates a possible role for the A. niger mutant strains in the biodegradation of oil-polluted environments for the development of ecofriendly technologies.

Design of a potent antibiotic peptide based on the active region of human defensin 5.

PubMed

Wang, Cheng; Shen, Mingqiang; Gohain, Neelakshi; Tolbert, William D; Chen, Fang; Zhang, Naixin; Yang, Ke; Wang, Aiping; Su, Yongping; Cheng, Tianmin; Zhao, Jinghong; Pazgier, Marzena; Wang, Junping

2015-04-09

Human defensin 5 (HD5) is a broad-spectrum antibacterial peptide with a C-terminal active region. To promote the development of this peptide into an antibiotic, we initially substituted Glu21 with Arg because it is an electronegative residue located around the active region. Although detrimental to dimer formation, the E21R substitution markedly enhanced the antibacterial activity of HD5 and increased its ability to penetrate cell membranes, demonstrating that increasing the electropositive charge compensated for the effect of dimer disruption. Subsequently, a partial Arg scanning mutagenesis was performed, and Thr7 was selected for replacement with Arg to further strengthen the antibacterial activity. The newly designed peptide, T7E21R-HD5, exhibited potent antibacterial activity, even in saline and serum solutions. In contrast to monomeric E21R-HD5, T7E21R-HD5 assembled into an atypical dimer with parallel β strands, thus expanding the role of increasing electropositive charge in bactericidal activity and providing a useful guide for further defensin-derived antibiotic design.

Aqueous phase hydrogenation of phenol catalyzed by Pd and PdAg on ZrO 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Resende, Karen A.; Hori, Carla E.; Noronha, Fabio B.

The impact of particle size of ZrO 2-supported Pd and of alloying with Ag was explored for hydrogenation of phenol in aqueous phase. Kinetic assessments were performed in a batch reactor, on monometallic Pd/ZrO 2 samples with different Pd loadings (0.5%, 1% and 2%), as well as on a 1% PdAg/ZrO 2 sample. The catalytic activity normalized to accessible Pd (turnover frequency, TOF) increased with the particle size of Pd. Reaction orders in phenol and H 2 and lower activation energies suggest that smaller particles bind the reacting substrates more strongly, leading to higher surface coverages by phenol. But, surprisingly,more » smaller Pd particles exhibited lower TOFs. The lower activity of the small Pd particles is attributed to lower activation entropies for the strongly bound species. Furthermore, the presence of Ag increased the catalyst activity by decreasing the apparent energy of activation and increasing the coverages of phenol and H 2, without negatively affecting the activation entropy.« less

Aqueous phase hydrogenation of phenol catalyzed by Pd and PdAg on ZrO 2

DOE PAGES

Resende, Karen A.; Hori, Carla E.; Noronha, Fabio B.; ...

2017-08-05

The impact of particle size of ZrO 2-supported Pd and of alloying with Ag was explored for hydrogenation of phenol in aqueous phase. Kinetic assessments were performed in a batch reactor, on monometallic Pd/ZrO 2 samples with different Pd loadings (0.5%, 1% and 2%), as well as on a 1% PdAg/ZrO 2 sample. The catalytic activity normalized to accessible Pd (turnover frequency, TOF) increased with the particle size of Pd. Reaction orders in phenol and H 2 and lower activation energies suggest that smaller particles bind the reacting substrates more strongly, leading to higher surface coverages by phenol. But, surprisingly,more » smaller Pd particles exhibited lower TOFs. The lower activity of the small Pd particles is attributed to lower activation entropies for the strongly bound species. Furthermore, the presence of Ag increased the catalyst activity by decreasing the apparent energy of activation and increasing the coverages of phenol and H 2, without negatively affecting the activation entropy.« less

The SLE transcriptome exhibits evidence of chronic endotoxin exposure and has widespread dysregulation of non-coding and coding RNAs.

PubMed

Shi, Lihua; Zhang, Zhe; Yu, Angela M; Wang, Wei; Wei, Zhi; Akhter, Ehtisham; Maurer, Kelly; Costa Reis, Patrícia; Song, Li; Petri, Michelle; Sullivan, Kathleen E

2014-01-01

Gene expression studies of peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE) have demonstrated a type I interferon signature and increased expression of inflammatory cytokine genes. Studies of patients with Aicardi Goutières syndrome, commonly cited as a single gene model for SLE, have suggested that accumulation of non-coding RNAs may drive some of the pathologic gene expression, however, no RNA sequencing studies of SLE patients have been performed. This study was designed to define altered expression of coding and non-coding RNAs and to detect globally altered RNA processing in SLE. Purified monocytes from eight healthy age/gender matched controls and nine SLE patients (with low-moderate disease activity and lack of biologic drug use or immune suppressive treatment) were studied using RNA-seq. Quantitative RT-PCR was used to validate findings. Serum levels of endotoxin were measured by ELISA. We found that SLE patients had diminished expression of most endogenous retroviruses and small nucleolar RNAs, but exhibited increased expression of pri-miRNAs. Splicing patterns and polyadenylation were significantly altered. In addition, SLE monocytes expressed novel transcripts, an effect that was replicated by LPS treatment of control monocytes. We further identified increased circulating endotoxin in SLE patients. Monocytes from SLE patients exhibit globally dysregulated gene expression. The transcriptome is not simply altered by the transcriptional activation of a set of genes, but is qualitatively different in SLE. The identification of novel loci, inducible by LPS, suggests that chronic microbial translocation could contribute to the immunologic dysregulation in SLE, a new potential disease mechanism.

Nuclear Factor Kappa B Activation Occurs in the Amnion Prior to Labour Onset and Modulates the Expression of Numerous Labour Associated Genes

PubMed Central

Lim, Sheri; MacIntyre, David A.; Lee, Yun S.; Khanjani, Shirin; Terzidou, Vasso; Teoh, T. G.; Bennett, Phillip R.

2012-01-01

Background Prior to the onset of human labour there is an increase in the synthesis of prostaglandins, cytokines and chemokines in the fetal membranes, particular the amnion. This is associated with activation of the transcription factor nuclear factor kappa B (NFκB). In this study we characterised the level of NFκB activity in amnion epithelial cells as a measure of amnion activation in samples collected from women undergoing caesarean section at 39 weeks gestation prior to the onset of labour. Methodology/Principal Findings We found that a proportion of women exhibit low or moderate NFκB activity while other women exhibit high levels of NFκB activity (n = 12). This activation process does not appear to involve classical pathways of NFκB activation but rather is correlated with an increase in nuclear p65-Rel-B dimers. To identify the full range of genes upregulated in association with amnion activation, microarray analysis was performed on carefully characterised non-activated amnion (n = 3) samples and compared to activated samples (n = 3). A total of 919 genes were upregulated in response to amnion activation including numerous inflammatory genes such cyclooxygenase-2 (COX-2, 44-fold), interleukin 8 (IL-8, 6-fold), IL-1 receptor accessory protein (IL-1RAP, 4.5-fold), thrombospondin 1 (TSP-1, 3-fold) and, unexpectedly, oxytocin receptor (OTR, 24-fold). Ingenuity Pathway Analysis of the microarray data reveal the two main gene networks activated concurrently with amnion activation are i) cell death, cancer and morphology and ii) cell cycle, embryonic development and tissue development. Conclusions/Significance Our results indicate that assessment of amnion NFκB activation is critical for accurate sample classification and subsequent interpretation of data. Collectively, our data suggest amnion activation is largely an inflammatory event that occurs in the amnion epithelial layer as a prelude to the onset of labour. PMID:22485186

Ontogenetic prey size selection in snakes: predator size and functional limitations to handling minimum prey sizes.

PubMed

Hampton, Paul M

2018-02-01

As body size increases, some predators eliminate small prey from their diet exhibiting an ontogenetic shift toward larger prey. In contrast, some predators show a telescoping pattern of prey size in which both large and small prey are consumed with increasing predator size. To explore a functional explanation for the two feeding patterns, I examined feeding effort as both handling time and number of upper jaw movements during ingestion of fish of consistent size. I used a range of body sizes from two snake species that exhibit ontogenetic shifts in prey size (Nerodia fasciata and N. rhombifer) and a species that exhibits telescoping prey size with increased body size (Thamnophis proximus). For the two Nerodia species, individuals with small or large heads exhibited greater difficulty in feeding effort compared to snakes of intermediate size. However, for T. proximus measures of feeding effort were negatively correlated with head length and snout-vent length (SVL). These data indicate that ontogenetic shifters of prey size develop trophic morphology large enough that feeding effort increases for disproportionately small prey. I also compared changes in body size among the two diet strategies for active foraging snake species using data gleaned from the literature to determine if increased change in body size and thereby feeding morphology is observable in snakes regardless of prey type or foraging habitat. Of the 30 species sampled from literature, snakes that exhibit ontogenetic shifts in prey size have a greater magnitude of change in SVL than species that have telescoping prey size patterns. Based upon the results of the two data sets above, I conclude that ontogenetic shifts away from small prey occur in snakes due, in part, to growth of body size and feeding structures beyond what is efficient for handling small prey. Copyright © 2017. Published by Elsevier GmbH.

Myostatin promotes distinct responses on protein metabolism of skeletal and cardiac muscle fibers of rodents.

PubMed

Manfredi, L H; Paula-Gomes, S; Zanon, N M; Kettelhut, I C

2017-10-19

Myostatin is a novel negative regulator of skeletal muscle mass. Myostatin expression is also found in heart in a much less extent, but it can be upregulated in pathological conditions, such as heart failure. Myostatin may be involved in inhibiting protein synthesis and/or increasing protein degradation in skeletal and cardiac muscles. Herein, we used cell cultures and isolated muscles from rats to determine protein degradation and synthesis. Muscles incubated with myostatin exhibited an increase in proteolysis with an increase of Atrogin-1, MuRF1 and LC3 genes. Extensor digitorum longus muscles and C2C12 myotubes exhibited a reduction in protein turnover. Cardiomyocytes showed an increase in proteolysis by activating autophagy and the ubiquitin proteasome system, and a decrease in protein synthesis by decreasing P70S6K. The effect of myostatin on protein metabolism is related to fiber type composition, which may be associated to the extent of atrophy mediated effect of myostatin on muscle.

Myostatin promotes distinct responses on protein metabolism of skeletal and cardiac muscle fibers of rodents

PubMed Central

Manfredi, L.H.; Paula-Gomes, S.; Zanon, N.M.; Kettelhut, I.C.

2017-01-01

Myostatin is a novel negative regulator of skeletal muscle mass. Myostatin expression is also found in heart in a much less extent, but it can be upregulated in pathological conditions, such as heart failure. Myostatin may be involved in inhibiting protein synthesis and/or increasing protein degradation in skeletal and cardiac muscles. Herein, we used cell cultures and isolated muscles from rats to determine protein degradation and synthesis. Muscles incubated with myostatin exhibited an increase in proteolysis with an increase of Atrogin-1, MuRF1 and LC3 genes. Extensor digitorum longus muscles and C2C12 myotubes exhibited a reduction in protein turnover. Cardiomyocytes showed an increase in proteolysis by activating autophagy and the ubiquitin proteasome system, and a decrease in protein synthesis by decreasing P70S6K. The effect of myostatin on protein metabolism is related to fiber type composition, which may be associated to the extent of atrophy mediated effect of myostatin on muscle. PMID:29069231

Task positive and default mode networks during a working memory in children with primary monosymptomatic nocturnal enuresis and healthy controls.

PubMed

Zhang, Kaihua; Ma, Jun; Lei, Du; Wang, Mengxing; Zhang, Jilei; Du, Xiaoxia

2015-10-01

Nocturnal enuresis is a common developmental disorder in children, and primary monosymptomatic nocturnal enuresis (PMNE) is the dominant subtype. This study investigated brain functional abnormalities that are specifically related to working memory in children with PMNE using function magnetic resonance imaging (fMRI) in combination with an n-back task. Twenty children with PMNE and 20 healthy children, group-matched for age and sex, participated in this experiment. Several brain regions exhibited reduced activation during the n-back task in children with PMNE, including the right precentral gyrus and the right inferior parietal lobule extending to the postcentral gyrus. Children with PMNE exhibited decreased cerebral activation in the task-positive network, increased task-related cerebral deactivation during a working memory task, and longer response times. Patients exhibited different brain response patterns to different levels of working memory and tended to compensate by greater default mode network deactivation to sustain normal working memory function. Our results suggest that children with PMNE have potential working memory dysfunction.

Effects of a pediatric weight management program with and without active video games a randomized trial.

PubMed

Trost, Stewart G; Sundal, Deborah; Foster, Gary D; Lent, Michelle R; Vojta, Deneen

2014-05-01

Active video games may offer an effective strategy to increase physical activity in overweight and obese children. However, the specific effects of active gaming when delivered within the context of a pediatric weight management program are unknown. To evaluate the effects of active video gaming on physical activity and weight loss in children participating in an evidence-based weight management program delivered in the community. Group-randomized clinical trial conducted during a 16-week period in YMCAs and schools located in Massachusetts, Rhode Island, and Texas. Seventy-five overweight or obese children (41 girls [55%], 34 whites [45%], 20 Hispanics [27%], and 17 blacks [23%]) enrolled in a community-based pediatric weight management program. Mean (SD) age of the participants was 10.0 (1.7) years; body mass index (BMI) z score, 2.15 (0.40); and percentage overweight from the median BMI for age and sex, 64.3% (19.9%). All participants received a comprehensive family-based pediatric weight management program (JOIN for ME). Participants in the program and active gaming group received hardware consisting of a game console and motion capture device and 1 active game at their second treatment session and a second game in week 9 of the program. Participants in the program-only group were given the hardware and 2 games at the completion of the 16-week program. Objectively measured daily moderate-to-vigorous and vigorous physical activity, percentage overweight, and BMI z score. Participants in the program and active gaming group exhibited significant increases in moderate-to-vigorous (mean [SD], 7.4 [2.7] min/d) and vigorous (2.8 [0.9] min/d) physical activity at week 16 (P < .05). In the program-only group, a decline or no change was observed in the moderate-to-vigorous (mean [SD] net difference, 8.0 [3.8] min/d; P = .04) and vigorous (3.1 [1.3] min/d; P = .02) physical activity. Participants in both groups exhibited significant reductions in percentage overweight and BMI z scores at week 16. However, the program and active gaming group exhibited significantly greater reductions in percentage overweight (mean [SD], -10.9%[1.6%] vs -5.5%[1.5%]; P = .02) and BMI z score (-0.25 [0.03] vs -0.11 [0.03]; P < .001). CONCLUSIONS AND RELEVANCE Incorporating active video gaming into an evidence-based pediatric weight management program has positive effects on physical activity and relative weight. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01757925.

Flexibility and Stability Trade-Off in Active Site of Cold-Adapted Pseudomonas mandelii Esterase EstK.

PubMed

Truongvan, Ngoc; Jang, Sei-Heon; Lee, ChangWoo

2016-06-28

Cold-adapted enzymes exhibit enhanced conformational flexibility, especially in their active sites, as compared with their warmer-temperature counterparts. However, the mechanism by which cold-adapted enzymes maintain their active site stability is largely unknown. In this study, we investigated the role of conserved D308-Y309 residues located in the same loop as the catalytic H307 residue in the cold-adapted esterase EstK from Pseudomonas mandelii. Mutation of D308 and/or Y309 to Ala or deletion resulted in increased conformational flexibility. Particularly, the D308A or Y309A mutant showed enhanced substrate affinity and catalytic rate, as compared with wild-type EstK, via enlargement of the active site. However, all mutant EstK enzymes exhibited reduced thermal stability. The effect of mutation was greater for D308 than Y309. These results indicate that D308 is not preferable for substrate selection and catalytic activity, whereas hydrogen bond formation involving D308 is critical for active site stabilization. Taken together, conformation of the EstK active site is constrained via flexibility-stability trade-off for enzyme catalysis and thermal stability. Our study provides further insights into active site stabilization of cold-adapted enzymes.

Proanthocyanidins from the bark of Hamamelis virginiana exhibit antimutagenic properties against nitroaromatic compounds.

PubMed

Dauer, A; Metzner, P; Schimmer, O

1998-05-01

The antimutagenic activity of Hamamelis virginiana bark was examined in the Ames assay. A commercial tincture and a methanolic extract showed dose-dependent inhibitory effects on mutagenicity induced by 2-nitrofluorene. Tannin-free samples did not display any inhibition. Bioassay-guided fractionation resulted in the isolation of two active fractions which were shown to contain oligomeric, proanthocyanidins. They were capable of inhibiting the mutagenicity of selected nitroaromatic compounds. The mechanism of antimutagenic action was also studied. The proanthocyanidins did not act as bioantimutagens, but rather as direct-acting desmutagens. The antimutagenic effect increased with an increasing degree of polymerisation in the proanthocyanidins. The most active fraction consisted of catechin and gallocatechin oligomers with an average polymerisation degree of 9.2.

Influence of substrate modification and C-terminal truncation on the active site structure of substrate-bound heme oxygenase from Neisseriae meningitidis; A 1H NMR study†

PubMed Central

Peng, Dungeng; Satterlee, James D.; Ma, Li-Hua; Dallas, Jerry L.; Smith, Kevin M.; Zhang, Xuhong; Sato, Michihiko; La Mar, Gerd N.

2011-01-01

Heme oxygenase, HO, from the pathogenic bacterium N. meningitidis, NmHO, which secures host iron, shares many properties with mammalian HOs, but also exhibits some key differences. The crystal structure appears more compact and the crystal-undetected C-terminus interacts with substrate in solution. The unique nature of substrate-protein, specifically pyrrole-I/II-helix-2, peripheral interactions in NmHO are probed by 2D 1H NMR to reveal unique structural features controlling substrate orientation. The thermodynamics of substrate orientational isomerism are mapped for substrates with individual vinyl → methyl → hydrogen substitutions and with enzyme C-terminal deletions. NmHO exhibits significantly stronger orientational preference, reflecting much stronger and selective pyrrole-I/II interactions with the protein matrix, than in mammalian HOs. Thus, replacing bulky vinyls with hydrogens results in a 180° rotation of substrate about the α,γ-meso axis in the active site. A "collapse" of the substrate pocket as substrate size decreases is reflected in movement of helix-2 toward the substrate as indicated by significant and selective increased NOESY cross peak intensity, increase in steric Fe-CN tilt reflected in the orientation of the major magnetic axis, and decrease in steric constraints controlling the rate of aromatic ring reorientation. The active site of NmHO appears "stressed" for native protohemin and its "collapse" upon replacing vinyls by hydrogen leads to a factor ~102 increase in substrate affinity. Interaction of the C-terminus with the active site destabilizes the crystallographic protohemin orientation by ~0.7 kcal/mol, which is consistent with optimizing the His207-Asp27 H-bond. Implications of the active site "stress" for product release are discussed. PMID:21870860

Evolution of availability of curcumin inside poly-lactic-co-glycolic acid nanoparticles: impact on antioxidant and antinitrosant properties

PubMed Central

Betbeder, Didier; Lipka, Emmanuelle; Howsam, Mike; Carpentier, Rodolphe

2015-01-01

Purpose Curcumin exhibits antioxidant properties potentially beneficial for human health; however, its use in clinical applications is limited by its poor solubility and relative instability. Nanoparticles exhibit interesting features for the efficient distribution and delivery of curcumin into cells, and could also increase curcumin stability in biological systems. There is a paucity of information regarding the evolution of the antioxidant properties of nanoparticle-encapsulated curcumin. Method We described a simple method of curcumin encapsulation in poly-lactic-co-glycolic acid (PLGA) nanoparticles without the use of detergent. We assessed, in epithelial cells and in an acellular model, the evolution of direct antioxidant and antinitrosant properties of free versus PLGA-encapsulated curcumin after storage under different conditions (light vs darkness, 4°C vs 25°C vs 37°C). Results In epithelial cells, endocytosis and efflux pump inhibitors showed that the increased antioxidant activity of PLGA-encapsulated curcumin relied on bypassing the efflux pump system. Acellular assays showed that the antioxidant effect of curcumin was greater when loaded in PLGA nanoparticles. Furthermore, we observed that light decreased, though heat restored, antioxidant activity of PLGA-encapsulated curcumin, probably by modulating the accessibility of curcumin to reactive oxygen species, an observation supported by results from quenching experiments. Moreover, we demonstrated a direct antinitrosant activity of curcumin, enhanced by PLGA encapsulation, which was increased by light exposure. Conclusion These results suggest that the antioxidant and antinitrosant activities of encapsulated curcumin are light sensitive and that nanoparticle modifications over time and with temperature may facilitate curcumin contact with reactive oxygen species. These results highlight the importance of understanding effects of nanoparticle maturation on an encapsulated drug’s activity. PMID:26345627

Structure-activity relationship of ortho- and meta-phenol based LFA-1 ICAM inhibitors.

PubMed

Lin, Edward Yin-Shiang; Guckian, Kevin M; Silvian, Laura; Chin, Donovan; Boriack-Sjodin, P Ann; van Vlijmen, Herman; Friedman, Jessica E; Scott, Daniel M

2008-10-01

LFA-1 ICAM inhibitors based on ortho- and meta-phenol templates were designed and synthesized by Mitsunobu chemistry. The selection of targets was guided by X-ray co-crystal data, and led to compounds which showed an up to 30-fold increase in potency over reference compound 1 in the LFA-1/ICAM1-Ig assay. The most active compound exploited a new hydrogen bond to the I-domain and exhibited subnanomolar potency.

Increased production of biomass-degrading enzymes by double deletion of creA and creB genes involved in carbon catabolite repression in Aspergillus oryzae.

PubMed

Ichinose, Sakurako; Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

2018-02-01

In a previous study, we reported that a double gene deletion mutant for CreA and CreB, which constitute the regulatory machinery involved in carbon catabolite repression, exhibited improved production of α-amylase compared with the wild-type strain and single creA or creB deletion mutants in Aspergillus oryzae. Because A. oryzae can also produce biomass-degrading enzymes, such as xylolytic and cellulolytic enzymes, we examined the production levels of those enzymes in deletion mutants in this study. Xylanase and β-glucosidase activities in the wild-type were hardly detected in submerged culture containing xylose as the carbon source, whereas those enzyme activities were significantly increased in the single creA deletion (ΔcreA) and double creA and creB deletion (ΔcreAΔcreB) mutants. In particular, the ΔcreAΔcreB mutant exhibited >100-fold higher xylanase and β-glucosidase activities than the wild-type. Moreover, in solid-state culture, the β-glucosidase activity of the double deletion mutant was >7-fold higher than in the wild-type. These results suggested that deletion of both creA and creB genes could also efficiently improve the production levels of biomass-degrading enzymes in A. oryzae. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Carefully designed oxygen-containing functional groups and defects of porous carbon spheres with UV-O3 treatment and their enhanced catalytic performance

NASA Astrophysics Data System (ADS)

Han, Weiliang; Huang, Xiaosheng; Lu, Gongxuan; Tang, Zhicheng

2018-04-01

In this paper, the support surface properties (surface oxygen-containing functional groups and structure defects) of porous carbon spheres (PCSs) were carefully designed by as UV assisted O3 technology. CO catalytic oxidation reactions performed over the supported Pd-Ce catalysts on modified porous carbon spheres. Results illustrated that the Pd-Ce/PCSs catalysts exhibited high CO catalytic activity, which were increased at first, and then decreased with UV assistant-O3 treatment time. The Pd-Ce/PCSs-30 catalyst exhibited superior activity and T100 was only 15 °C. Moreover, the Pd-Ce/PCSs-30 catalyst obtained an excellent stability, and 100% CO conversion could be maintained as the time on stream evolutes up to 16h in the presence of H2O in the feed. Based on characterization results, there were two main factors: (a) the surface area and pore volume were decreased with UV-O3 treatment, leading to the enhancement of Pd-Ce particle size, and the decrease of Pd-Ce nanoparticle dispersion and mass transfer efficiency, as well as the decrease of catalytic activity of Pd-Ce/PCSs, (b) the surface oxygen content and defect sites of PCSs were raised by UV-O3 treatment, which could improve surface loading of Pd, Ce and enhance Pdsbnd Osbnd Ce bonding interactions, thereby increasing the activity of Pd-Ce/PCSs.

One stone, two birds: silica nanospheres significantly increase photocatalytic activity and colloidal stability of photocatalysts

NASA Astrophysics Data System (ADS)

Rasamani, Kowsalya D.; Foley, Jonathan J., IV; Sun, Yugang

2018-03-01

Silver-doped silver chloride [AgCl(Ag)] nanoparticles represent a unique class of visible-light-driven photocatalysts, in which the silver dopants introduce electron-abundant mid-gap energy levels to lower the bandgap of AgCl. However, free-standing AgCl(Ag) nanoparticles, particularly those with small sizes and large surface areas, exhibit low colloidal stability and low compositional stability upon exposure to light irradiation, leading to easy aggregation and conversion to metallic silver and thus a loss of photocatalytic activity. These problems could be eliminated by attaching the small AgCl(Ag) nanoparticles to the surfaces of spherical dielectric silica particles with submicrometer sizes. The high optical transparency in the visible spectral region (400-800 nm), colloidal stability, and chemical/electronic inertness displayed by the silica spheres make them ideal for supporting photocatalysts and significantly improving their stability. The spherical morphology of the dielectric silica particles can support light scattering resonances to generate significantly enhanced electric fields near the silica particle surfaces, on which the optical absorption cross-section of the AgCl(Ag) nanoparticles is dramatically increased to promote their photocatalytic activity. The hybrid silica/AgCl(Ag) structures exhibit superior photocatalytic activity and stability, suitable for supporting photocatalysis sustainably; for instance, their efficiency in the photocatalytic decomposition of methylene blue decreases by only ˜9% even after ten cycles of operation.

Blueberry and EpidiferphaneTM (EDP) enhance calcium buffering in rat hippocampal cells and reduce stress signalling in microglial cells

USDA-ARS?s Scientific Manuscript database

Age-related decrements are thought to result from increased susceptibility to and accumulating effects of oxidative stress and inflammation. Some foods and food compounds contain bioactive phytochemicals that exhibit potent antioxidant and anti-inflammatory activities, and these foods have been show...

To Decrease the Negative Behavior of High School Students by Increasing Pro-Social Behavior.

ERIC Educational Resources Information Center

Cabeza, Catherine

This practicum was designed to reduce the instances of negative behavior exhibited by students in a special education setting. Various interventions were initiated and implemented, such as engaging students in conflict resolution workshops, involving student in extracurricular activities so as to help them use leisure time constructively, and…

Governing Knowledge: The Formalization Dilemma in the Governance of the Public Sciences

ERIC Educational Resources Information Center

Woelert, Peter

2015-01-01

This paper offers a conceptually novel contribution to the understanding of the distinctive governance challenges arising from the increasing reliance on formalized knowledge in the governance of research activities. It uses the current Australian research governance system as an example--a system which exhibits a comparatively strong degree of…

Vegetation and environmental controls on soil respiration in a pinon-juniper woodland

Treesearch

Sandra A. White

2008-01-01

Soil respiration (RS) responds to changes in plant and microbial activity and environmental conditions. In arid ecosystems of the southwestern USA, soil moisture exhibits large fluctuations because annual and seasonal precipitation inputs are highly variable, with increased variability expected in the future. Patterns of soil moisture, and periodic severe drought, are...

Regulatory brain development: balancing emotion and cognition.

PubMed

Perlman, Susan B; Pelphrey, Kevin A

2010-01-01

Emotion regulation is a critical aspect of children's social development, yet few studies have examined the brain mechanisms involved in its development. Theoretical accounts have conceptualized emotion regulation as relying on prefrontal control of limbic regions, specifying the anterior cingulate cortex (ACC) as a key brain region. Functional magnetic resonance imaging in 5- to 11-year-olds during emotion regulation and processing of emotionally expressive faces revealed that older children preferentially recruited the more dorsal “cognitive” areas of the ACC, while younger children preferentially engaged the more ventral “emotional” areas. Additionally, children with more fearful temperaments exhibited more ventral ACC activity while less fearful children exhibited increased activity in the dorsal ACC. These findings provide insight into a potential neurobiological mechanism underlying well-documented behavioral and cognitive changes from more emotional to more cognitive regulatory strategies with increasing age, as well as individual differences in this developmental process as a function of temperament. Our results hold important implications for our understanding of normal development and should also help to inform our understanding and management of emotional disorders. © 2010 Psychology Press

Spontaneous synthesis of gold nanoparticles on gum arabic-modified iron oxide nanoparticles as a magnetically recoverable nanocatalyst.

PubMed

Wu, Chien-Chen; Chen, Dong-Hwang

2012-06-19

A novel magnetically recoverable Au nanocatalyst was fabricated by spontaneous green synthesis of Au nanoparticles on the surface of gum arabic-modified Fe3O4 nanoparticles. A layer of Au nanoparticles with thickness of about 2 nm was deposited on the surface of gum arabic-modified Fe3O4 nanoparticles, because gum arabic acted as a reducing agent and a stabilizing agent simultaneously. The resultant magnetically recoverable Au nanocatalyst exhibited good catalytic activity for the reduction of 4-nitrophenol with sodium borohydride. The rate constants evaluated in terms of pseudo-first-order kinetic model increased with increase in the amount of Au nanocatalyst or decrease in the initial concentration of 4-nitrophenol. The kinetic data suggested that this catalytic reaction was diffusion-controlled, owing to the presence of gum arabic layer. In addition, this nanocatalyst exhibited good stability. Its activity had no significant decrease after five recycles. This work is useful for the development and application of magnetically recoverable Au nanocatalyst on the basis of green chemistry principles.

Heat shock protein defenses in the neo- and allocortex of the telencephalon

PubMed Central

Posimo, Jessica M.; Weilnau, Justin N.; Gleixner, Amanda M.; Broeren, Matthew T.; Weiland, Nicole L.; Brodsky, Jeffrey L.; Wipf, Peter; Leak, Rehana K.

2015-01-01

The telencephalic allocortex develops protein inclusions before the neocortex in many age-related proteinopathies. One major defense mechanism against proteinopathic stress is the heat shock protein (Hsp) network. We therefore contrasted Hsp defenses in stressed primary neo- and allocortical cells. Neocortical neurons were more resistant to the proteasome inhibitor MG132 than neurons from three allocortical subregions: entorhinal cortex, piriform cortex, and hippocampus. However, allocortical neurons exhibited higher MG132-induced increases in Hsp70 and Hsc70. MG132-treated allocortical neurons also exhibited greater levels of protein ubiquitination. Inhibition of Hsp70/Hsc70 activity synergistically exacerbated MG132 toxicity in allocortical neurons more than neocortical neurons, suggesting that the allocortex is more reliant on these Hsp defenses. In contrast, astrocytes harvested from neo- or allocortex did not differ in their response to Hsp70/Hsc70 inhibition. Consistent with the idea that chaperones are maximally engaged in allocortical neurons, an increase in Hsp70/Hsc70 activity was protective only in neocortical neurons. Finally, the levels of select Hsps were altered in neocortex and allocortex in vivo with aging. PMID:25771395

Intelligence related upper alpha desynchronization in a semantic memory task.

PubMed

Doppelmayr, M; Klimesch, W; Hödlmoser, K; Sauseng, P; Gruber, W

2005-07-30

Recent evidence shows that event-related (upper) alpha desynchronization (ERD) is related to cognitive performance. Several studies observed a positive, some a negative relationship. The latter finding, interpreted in terms of the neural efficiency hypothesis, suggests that good performance is associated with a more 'efficient', smaller extent of cortical activation. Other studies found that ERD increases with semantic processing demands and that this increase is larger for good performers. Studies supporting the neural efficiency hypothesis used tasks that do not specifically require semantic processing. Thus, we assume that the lack of semantic processing demands may at least in part be responsible for the reduced ERD. In the present study we measured ERD during a difficult verbal-semantic task. The findings demonstrate that during semantic processing, more intelligent (as compared to less intelligent) subjects exhibited a significantly larger upper alpha ERD over the left hemisphere. We conclude that more intelligent subjects exhibit a more extensive activation in a semantic processing system and suggest that divergent findings regarding the neural efficiency hypotheses are due to task specific differences in semantic processing demands.

Age-related differences in early novelty processing: Using PCA to parse the overlapping anterior P2 and N2 components

PubMed Central

Daffner, Kirk R.; Alperin, Brittany R.; Mott, Katherine K.; Tusch, Erich; Holcomb, Phillip J.

2015-01-01

Previous work demonstrated age-associated increases in the anterior P2 and age-related decreases in the anterior N2 in response to novel stimuli. Principal component analysis (PCA) was used to determine if the inverse relationship between these components was due to their temporal and spatial overlap. PCA revealed an early anterior P2, sensitive to task relevance, and a late anterior P2, responsive to novelty, both exhibiting age-related amplitude increases. A PCA factor representing the anterior N2, sensitive to novelty, exhibited age-related amplitude decreases. The late P2 and N2 to novels inversely correlated. Larger late P2 amplitude to novels was associated with better behavioral performance. Age-related differences in the anterior P2 and N2 to novel stimuli likely represent age-associated changes in independent cognitive operations. Enhanced anterior P2 activity (indexing augmentation in motivational salience) may be a compensatory mechanism for diminished anterior N2 activity (indexing reduced ability of older adults to process ambiguous representations). PMID:25596483

Spontaneous synthesis of gold nanoparticles on gum arabic-modified iron oxide nanoparticles as a magnetically recoverable nanocatalyst

PubMed Central

2012-01-01

A novel magnetically recoverable Au nanocatalyst was fabricated by spontaneous green synthesis of Au nanoparticles on the surface of gum arabic-modified Fe3O4 nanoparticles. A layer of Au nanoparticles with thickness of about 2 nm was deposited on the surface of gum arabic-modified Fe3O4 nanoparticles, because gum arabic acted as a reducing agent and a stabilizing agent simultaneously. The resultant magnetically recoverable Au nanocatalyst exhibited good catalytic activity for the reduction of 4-nitrophenol with sodium borohydride. The rate constants evaluated in terms of pseudo-first-order kinetic model increased with increase in the amount of Au nanocatalyst or decrease in the initial concentration of 4-nitrophenol. The kinetic data suggested that this catalytic reaction was diffusion-controlled, owing to the presence of gum arabic layer. In addition, this nanocatalyst exhibited good stability. Its activity had no significant decrease after five recycles. This work is useful for the development and application of magnetically recoverable Au nanocatalyst on the basis of green chemistry principles. PMID:22713480

[Combined effects of copper and simulated acid rain on copper accumulation, growth, and antioxidant enzyme activities of Rumex acetosa].

PubMed

He, Shan-Ying; Gao, Yong-Jie; Shentu, Jia-Li; Chen, Kun-Bai

2011-02-01

A pot experiment was conducted to study the combined effects of Cu (0-1500 mg x kg(-1)) and simulated acid rain (pH 2.5-5.6) on the copper accumulation, growth, and antioxidant enzyme activities of Rumex acetosa. With the increasing concentration of soil Cu, the Cu accumulation in R. acetosa increased, being higher in root than in stem and leaf. The exposure to low pH acid rain promoted the Cu uptake by R. acetosa. With the increase of soil Cu concentration and/or of acid rain acidity, the biomass of R. acetosa decreased, leaf and root MDA contents increased and had good correlation with soil Cu concentration, and the SOD and POD activities in leaf and root displayed a decreasing trend after an initial increase. This study showed that R. acetosa had a strong adaptive ability to Cu and acid rain stress, exhibiting a high application potential in the remediation of Cu-contaminated soil in acid rain areas.

Enhanced performance of Zn(II)-doped lead-acid batteries with electrochemical active carbon in negative mass

NASA Astrophysics Data System (ADS)

Xiang, Jiayuan; Hu, Chen; Chen, Liying; Zhang, Dong; Ding, Ping; Chen, Dong; Liu, Hao; Chen, Jian; Wu, Xianzhang; Lai, Xiaokang

2016-10-01

The effect and mechanism of Zn(II) on improving the performances of lead-acid cell with electrochemical active carbon (EAC) in negative mass is investigated. The hydrogen evolution of the cell is significantly reduced due to the deposition of Zn on carbon surface and the increased porosity of negative mass. Zn(II) additives can also improve the low-temperature and high-rate capacities of the cell with EAC in negative mass, which ascribes to the formation of Zn on lead and carbon surface that constructs a conductive bridge among the active mass. Under the co-contribution of EAC and Zn(II), the partial-state-of-charge cycle life is greatly prolonged. EAC optimizes the NAM structure and porosity to enhance the charge acceptance and retard the lead sulfate accumulation. Zn(II) additive reduces the hydrogen evolution during charge process and improves the electric conductivity of the negative electrode. The cell with 0.6 wt% EAC and 0.006 wt% ZnO in negative mass exhibits 90% reversible capacity of the initial capacity after 2100 cycles. In contrast, the cell with 0.6 wt% EAC exhibits 84% reversible capacity after 2100 cycles and the control cell with no EAC and Zn(II) exhibits less than 80% reversible capacity after 1350 cycles.

External immunity in ant societies: sociality and colony size do not predict investment in antimicrobials

PubMed Central

Halawani, Omar; Pearson, Bria; Mathews, Stephanie; López-Uribe, Margarita M.; Dunn, Robert R.; Smith, Adrian A.

2018-01-01

Social insects live in dense groups with a high probability of disease transmission and have therefore faced strong pressures to develop defences against pathogens. For this reason, social insects have been hypothesized to invest in antimicrobial secretions as a mechanism of external immunity to prevent the spread of disease. However, empirical studies linking the evolution of sociality with increased investment in antimicrobials have been relatively few. Here we quantify the strength of antimicrobial secretions among 20 ant species that cover a broad spectrum of ant diversity and colony sizes. We extracted external compounds from ant workers to test whether they inhibited the growth of the bacterium Staphylococcus epidermidis. Because all ant species are highly social, we predicted that all species would exhibit some antimicrobial activity and that species that form the largest colonies would exhibit the strongest antimicrobial response. Our comparative approach revealed that strong surface antimicrobials are common to particular ant clades, but 40% of species exhibited no antimicrobial activity at all. We also found no correlation between antimicrobial activity and colony size. Rather than relying on antimicrobial secretions as external immunity to control pathogen spread, many ant species have probably developed alternative strategies to defend against disease pressure. PMID:29515850

Reactive oxygen radicals and gaseous transmitters in carotid body activation by intermittent hypoxia.

PubMed

Prabhakar, Nanduri R; Peng, Ying-Jie; Yuan, Guoxiang; Nanduri, Jayasri

2018-05-01

Sleep apnea is a prevalent respiratory disease characterized by periodic cessation of breathing during sleep causing intermittent hypoxia (IH). Sleep apnea patients and rodents exposed to IH exhibit elevated sympathetic nerve activity and hypertension. A heightened carotid body (CB) chemoreflex has been implicated in causing autonomic abnormalities in IH-treated rodents and in sleep apnea patients. The purpose of this article is to review the emerging evidence showing that interactions between reactive oxygen species (ROS) and gaseous transmitters as a mechanism cause hyperactive CB by IH. Rodents treated with IH exhibit markedly elevated ROS in the CB, which is due to transcriptional upregulation of pro-oxidant enzymes by hypoxia-inducible factor (HIF)-1 and insufficient transcriptional regulation of anti-oxidant enzymes by HIF-2. ROS, in turn, increases cystathionine γ-lyase (CSE)-dependent H 2 S production in the CB. Blockade of H 2 S synthesis prevents IH-evoked CB activation. However, the effects of ROS on H 2 S production are not due to direct effects on CSE enzyme activity but rather due to inactivation of heme oxygenase-2 (HO-2), a carbon monoxide (CO) producing enzyme. CO inhibits H 2 S production through inactivation of CSE by PKG-dependent phosphorylation. During IH, reduced CO production resulting from inactivation of HO-2 by ROS releases the inhibition of CO on CSE thereby increasing H 2 S. Inhibiting H 2 S synthesis prevented IH-evoked sympathetic activation and hypertension.

Effects of MAOA-Genotype, Alcohol Consumption, and Aging on Violent Behavior

PubMed Central

Tikkanen, Roope; Sjöberg, Rickard L.; Ducci, Francesca; Goldman, David; Holi, Matti; Tiihonen, Jari; Virkkunen, Matti

2009-01-01

Background Environmental factors appear to interact with a functional polymorphism (MAOA-LPR) in the promoter region of the monoamine oxidase A gene (MAOA) in determining some forms of antisocial behavior. However, how MAOA-LPR modulates the effects of other factors such as alcohol consumption related to antisocial behavior is not completely understood. Methods This study examines the conjunct effect of MAOA-LPR, alcohol consumption, and aging on the risk for violent behavior. Recidivism in severe impulsive violent behavior was assessed after 7 to 15 years in a sample of 174 Finnish alcoholic offenders, the majority of whom exhibited antisocial or borderline personality disorder or both, and featured impulsive temperament traits. Results The risk for committing new acts of violence increased by 2.3% for each kilogram of increase in yearly mean alcohol consumption (p = 0.004) and decreased by 7.3% for every year among offenders carrying the high activity MAOA genotype. In contrast, alcohol consumption and aging failed to affect violent behavior in the low activity MAOA genotyped offenders. MAOA-LPR showed no main effect on the risk for recidivistic violence. Conclusions Violent offenders carrying the high activity MAOA genotype differ in several ways from carriers with the low activity MAOA risk allele previously associated with antisocial behavior. Finnish high activity MAOA genotyped risk alcoholics exhibiting antisocial behavior, high alcohol consumption, and abnormal alcohol-related impulsive and uncontrolled violence might represent an etiologically distinct alcohol dependence subtype. PMID:19120058

Segregating the cerebral mechanisms of antidepressants and placebo in fibromyalgia.

PubMed

Jensen, Karin B; Petzke, Frank; Carville, Serena; Choy, Ernest; Fransson, Peter; Gracely, Richard H; Vitton, Olivier; Marcus, Hanke; Williams, Steven C R; Ingvar, Martin; Kosek, Eva

2014-12-01

Antidepressant drugs are commonly used to treat fibromyalgia, but there is little knowledge about their mechanisms of action. The aim of this study was to compare the cerebral and behavioral response to positive treatment effects of antidepressants or placebo. Ninety-two fibromyalgia patients participated in a 12-week, double-blind, placebo-controlled clinical trial with milnacipran, a serotonin-norepinephrine reuptake inhibitor. Before and after treatment, measures of cerebral pain processing were obtained using functional magnetic resonance imaging. Also, there were stimulus response assessments of pressure pain, measures of weekly pain, and fibromyalgia impact. Following treatment, milnacipran responders exhibited significantly higher activity in the posterior cingulum compared with placebo responders. The mere exposure to milnacipran did not explain our findings because milnacipran responders exhibited increased activity also in comparison to milnacipran nonresponders. Stimulus response assessments revealed specific antihyperalgesic effects in milnacipran responders, which was also correlated with reduced clinical pain and with increased activation of the posterior cingulum. A short history of pain predicted positive treatment response to milnacipran. We report segregated neural mechanisms for positive responses to treatment with milnacipran and placebo, reflected in the posterior cingulum. The increase of pain-evoked activation in the posterior cingulum may reflect a normalization of altered default mode network processing, an alteration implicated in fibromyalgia pathophysiology. This study presents neural and psychophysical correlates to positive treatment responses in patients with fibromyalgia, treated with either milnacipran or placebo. The comparison between placebo responders and milnacipran responders may shed light on the specific mechanisms involved in antidepressant treatment of chronic pain. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.

Nucleus accumbens neurons encode Pavlovian approach behaviors: evidence from an autoshaping paradigm.

PubMed

Day, Jeremy J; Wheeler, Robert A; Roitman, Mitchell F; Carelli, Regina M

2006-03-01

Environmental stimuli predictive of appetitive events can elicit Pavlovian approach responses that enhance an organism's ability to track and secure natural rewards, but may also contribute to the compulsive nature of drug addiction. Here, we examined the activity of individual nucleus accumbens (NAc) neurons during an autoshaping paradigm. One conditioned stimulus (CS+, a retractable lever presented for 10 s) was immediately followed by the delivery of a 45-mg sucrose pellet to a food receptacle, while another stimulus (CS-, a separate retractable lever presented for 10 s) was never followed by sucrose. Approach responses directed at the CS+ and CS- were recorded as lever presses and had no experimental consequence. Rats (n = 9) selectively approached the CS+ on more than 80% of trials and were surgically prepared for electrophysiological recording. Of 76 NAc neurons, 57 cells (75%) exhibited increases and/or decreases in firing rate (i.e. termed 'phasically active') during the CS+ presentation and corresponding approach response. Forty-seven percent of phasically active cells (27 out of 57) were characterized by time-locked but transient increases in cell firing, while 53% (30 out of 57) showed a significant reduction in firing for the duration of the CS+. In contrast, the same excitatory subpopulation exhibited smaller increases in activity relative to CS- onset, while the inhibitory subpopulation showed no change in firing during the CS- period. The magnitude and prevalence of cue-related neural responses reported here indicates that the NAc encodes biologically significant, repetitive approach responses that may model the compulsive nature of drug addiction in humans.

Sex differences in brain activation to emotional stimuli: a meta-analysis of neuroimaging studies.

PubMed

Stevens, Jennifer S; Hamann, Stephan

2012-06-01

Substantial sex differences in emotional responses and perception have been reported in previous psychological and psychophysiological studies. For example, women have been found to respond more strongly to negative emotional stimuli, a sex difference that has been linked to an increased risk of depression and anxiety disorders. The extent to which such sex differences are reflected in corresponding differences in regional brain activation remains a largely unresolved issue, however, in part because relatively few neuroimaging studies have addressed this issue. Here, by conducting a quantitative meta-analysis of neuroimaging studies, we were able to substantially increase statistical power to detect sex differences relative to prior studies, by combining emotion studies which explicitly examined sex differences with the much larger number of studies that examined only women or men. We used an activation likelihood estimation approach to characterize sex differences in the likelihood of regional brain activation elicited by emotional stimuli relative to non-emotional stimuli. We examined sex differences separately for negative and positive emotions, in addition to examining all emotions combined. Sex differences varied markedly between negative and positive emotion studies. The majority of sex differences favoring women were observed for negative emotion, whereas the majority of the sex differences favoring men were observed for positive emotion. This valence-specificity was particularly evident for the amygdala. For negative emotion, women exhibited greater activation than men in the left amygdala, as well as in other regions including the left thalamus, hypothalamus, mammillary bodies, left caudate, and medial prefrontal cortex. In contrast, for positive emotion, men exhibited greater activation than women in the left amygdala, as well as greater activation in other regions including the bilateral inferior frontal gyrus and right fusiform gyrus. These meta-analysis findings indicate that the amygdala, a key region for emotion processing, exhibits valence-dependent sex differences in activation to emotional stimuli. The greater left amygdala response to negative emotion for women accords with previous reports that women respond more strongly to negative emotional stimuli, as well as with hypothesized links between increased neurobiological reactivity to negative emotion and increased prevalence of depression and anxiety disorders in women. The finding of greater left amygdala activation for positive emotional stimuli in men suggests that greater amygdala responses reported previously for men for specific types of positive stimuli may also extend to positive stimuli more generally. In summary, this study extends efforts to characterize sex differences in brain activation during emotion processing by providing the largest and most comprehensive quantitative meta-analysis to date, and for the first time examining sex differences as a function of positive vs. negative emotional valence. The current findings highlight the importance of considering sex as a potential factor modulating emotional processing and its underlying neural mechanisms, and more broadly, the need to consider individual differences in understanding the neurobiology of emotion. Copyright © 2012 Elsevier Ltd. All rights reserved.

Synergistic effect of muramyldipeptide with lipopolysaccharide or lipoteichoic acid to induce inflammatory cytokines in human monocytic cells in culture.

PubMed

Yang, S; Tamai, R; Akashi, S; Takeuchi, O; Akira, S; Sugawara, S; Takada, H

2001-04-01

An analog of 1alpha,25-dihydroxyvitamin D3, 22-oxyacalcitriol (OCT), differentiated human monocytic THP-1 and U937 cells to express membrane CD14 and rendered the cells responsive to bacterial cell surface components. Both THP-1 and U937 cells expressed Toll-like receptor 4 (TLR4) on the cell surface and TLR4 mRNA in the cells, irrespective of OCT treatment. In contrast, OCT-treated U937 cells scarcely expressed TLR2 mRNA, while OCT-treated THP-1 cells expressed this transcript. Muramyldipeptide (MDP) by itself exhibited only a weak ability to induce secretion of inflammatory cytokines such as interleukin-8 (IL-8) in the OCT-differentiated THP-1 cells but showed marked synergistic effects with Salmonella lipopolysaccharide (LPS) or lipoteichoic acid (LTA) from Staphylococcus aureus, both of which exhibited strong activities. Combinatory stimulation with LPS plus LTA did not show a synergistic effect on OCT-differentiated THP-1 cells. Similar results were observed in OCT-differentiated U937 cells, although combination experiments were carried out only with MDP plus LPS. Anti-CD14 monoclonal antibody (MAb) MY4, anti-TLR4 MAb HTA125, and the synthetic lipid A precursor LA-14-PP almost completely inhibited the IL-8-inducing activities of LTA as well as LPS on OCT-treated THP-1 cells, but these treatments increased MDP activity. OCT-treated THP-1 cells primed with MDP exhibited enhanced production of IL-8 upon stimulation with LPS, while the cells primed with LPS showed no change in production upon stimulation with MDP. MDP up-regulated mRNA expression of an adapter molecule to TLRs, MyD88, to an extent similar to that for LPS in OCT-treated THP-1 cells. These findings suggested that LTA as well as LPS activated human monocytic cells in a CD14- and TLR4-dependent manner, whereas MDP exhibited activity in a CD14-, TLR4-, and probably TLR2-independent manner and exhibited synergistic and priming effects on the cells for cytokine production in response to various bacterial components.

Sonographic appearance of the flexor tendon, volar plate, and A1 pulley with respect to the severity of trigger finger.

PubMed

Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo; Takeda, Mitsuhiro

2012-10-01

To evaluate trigger digits with sonography to determine morphological changes in the A1 pulley, flexor tendon, and volar plate in relation to the severity of triggering. We evaluated 67 trigger digits and graded them into 1 of 4 groups. We compared the groups according to severity and to contralateral fingers, which served as controls. The thickness of the flexor tendons under the A1 pulley was proportional to the severity of triggering. The anteroposterior thickness of the flexor tendon increased significantly among the grades exhibiting triggering regardless of the affected digit. However, in digits other than the thumb, tendon thickness increased even in the absence of active triggering. Thickening tended to be greater with finger flexion. The A1 pulley exhibited the greatest thickness and the volar plate exhibited significant thickening in the group that exhibited continuous triggering that was easily reduced with active extension (grade III). The flexor tendon thickened significantly before patients experienced triggering except in the thumb. In the thumb, the flexor tendon and A1 pulley thickened significantly only after patients exhibited triggering. Thickening of the volar plate appears to have an important role in continuous triggering. Although most clinicians can easily determine the severity of a trigger digit by clinical examination, ultrasound might be helpful for objectively understanding the severity and response to treatment, by examining the thickness of the flexor tendon and A1 pulley. In particular, sonographic measurement of the A1 pulley might be useful in judging the progression of trigger finger severity. In cases where a Doppler signal is detected inside the A1 pulley, more conservative therapies might be worth considering before surgery. Diagnostic ΙΙΙ. Copyright © 2012 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Expression of solute carrier 7A4 (SLC7A4) in the plasma membrane is not sufficient to mediate amino acid transport activity.

PubMed

Wolf, Sabine; Janzen, Annette; Vékony, Nicole; Martiné, Ursula; Strand, Dennis; Closs, Ellen I

2002-06-15

Member 4 of human solute carrier family 7 (SLC7A4) exhibits significant sequence homology with the SLC7 subfamily of human cationic amino acid transporters (hCATs) [Sperandeo, Borsani, Incerti, Zollo, Rossi, Zuffardi, Castaldo, Taglialatela, Andria and Sebastio (1998) Genomics 49, 230-236]. It is therefore often referred to as hCAT-4 even though no convincing transport activity has been shown for this protein. We expressed SLC7A4 in Xenopus laevis oocytes, but could not detect any transport activity for cationic, neutral or anionic amino acids or for the polyamine putrescine. In addition, human glioblastoma cells stably overexpressing a fusion protein between SLC7A4 and the enhanced green fluorescent protein (EGFP) did not exhibit an increased transport activity for l-arginine. The lack of transport activity was not due to a lack of SLC7A4 protein expression in the plasma membrane, as in both cell types SLC7A4-EGFP exhibited a similar subcellular localization and level of protein expression as functional hCAT-EGFP proteins. The expression of SLC7A4 can be induced in NT2 teratocarcinoma cells by treatment with retinoic acid. However, also for this endogenously expressed SLC7A4, we could not detect any transport activity for l-arginine. Our data demonstrate that the expression of SLC7A4 in the plasma membrane is not sufficient to induce an amino acid transport activity in X. laevis oocytes or human cells. Therefore, SLC7A4 is either not an amino acid transporter or it needs additional (protein) factor(s) to be functional.

Expression of solute carrier 7A4 (SLC7A4) in the plasma membrane is not sufficient to mediate amino acid transport activity.

PubMed Central

Wolf, Sabine; Janzen, Annette; Vékony, Nicole; Martiné, Ursula; Strand, Dennis; Closs, Ellen I

2002-01-01

Member 4 of human solute carrier family 7 (SLC7A4) exhibits significant sequence homology with the SLC7 subfamily of human cationic amino acid transporters (hCATs) [Sperandeo, Borsani, Incerti, Zollo, Rossi, Zuffardi, Castaldo, Taglialatela, Andria and Sebastio (1998) Genomics 49, 230-236]. It is therefore often referred to as hCAT-4 even though no convincing transport activity has been shown for this protein. We expressed SLC7A4 in Xenopus laevis oocytes, but could not detect any transport activity for cationic, neutral or anionic amino acids or for the polyamine putrescine. In addition, human glioblastoma cells stably overexpressing a fusion protein between SLC7A4 and the enhanced green fluorescent protein (EGFP) did not exhibit an increased transport activity for l-arginine. The lack of transport activity was not due to a lack of SLC7A4 protein expression in the plasma membrane, as in both cell types SLC7A4-EGFP exhibited a similar subcellular localization and level of protein expression as functional hCAT-EGFP proteins. The expression of SLC7A4 can be induced in NT2 teratocarcinoma cells by treatment with retinoic acid. However, also for this endogenously expressed SLC7A4, we could not detect any transport activity for l-arginine. Our data demonstrate that the expression of SLC7A4 in the plasma membrane is not sufficient to induce an amino acid transport activity in X. laevis oocytes or human cells. Therefore, SLC7A4 is either not an amino acid transporter or it needs additional (protein) factor(s) to be functional. PMID:12049641

Antiproliferative and Antioxidant Activities of Two Extracts of the Plant Species Euphorbia dendroides L.

PubMed

Ghout, Agena; Zellagui, Amar; Gherraf, Noureddine; Demirtas, Ibrahim; Ayse Sahin, Yaglioglu; Boukhenaf, Meriem; Lahouel, Mesbah; Nieto, Gema; Akkal, Salah

2018-04-20

Background: These days, the desire for naturally occurring antioxidants has significantly increased, especially for use in foodstuffs, cosmetics, and pharmaceutical products, to replace synthetic antioxidants that are regularly constrained due to their carcinogenicity. Methods : The study in hand aimed to appraise the antioxidant effect of two Euphorbia dendroides extracts using reducing power, anti-peroxidation, and DPPH (1,1 Diphenyl 2 Pycril Hydrazil) scavenging essays, in addition to the anticancer activity against two tumor cell lines, namely C6 (rat brain tumor)cells, and Hela (human uterus carcinoma)cell lines. Results : The results indicated that the ethyl acetate extract exhibited antiradical activity of 29.49%, higher than that of n -butanol extract (18.06%) at 100 µg/mL but much lower than that of gallic acid (78.21%).The ethyl acetate extract exhibits better reducing capacity and lipid peroxidation inhibitory activity compared to n -butanol extract but less than all tested standards. Moreover, the ethyl acetate extract was found to have an antiproliferative activity of more than 5-FU (5-fluoro-Uracil) against C6 cells at 250 µg/mL with IC 50 and IC 75 of 113.97, 119.49 µg/mL, respectively, and good cytotoxic activity against the Hela cell lines at the same concentration. The HPLC-TOF-MS (high performance liquid chromatography-Time-of-flight-Mass Spectrometry) analyses exposed the presence of various compounds, among which Gallic and Chlorogenic acids functioned as major compounds. Conclusions : The two extracts exhibited moderate anticancer abilities and behaved somewhat as average antioxidant agents. Based on the total phenolics and flavonoids contents, as well as HPLC results, it could be concluded that antiproliferative and antioxidant activities depend upon the content of different phenolics and flavonoids.

In vivo antioxidative property, antimicrobial and wound healing activity of flower extracts of Pyrostegia venusta (Ker Gawl) Miers.

PubMed

Roy, Purabi; Amdekar, Sarika; Kumar, Avnish; Singh, Rambir; Sharma, Poonam; Singh, Vinod

2012-03-06

Pyrostegia venusta (Ker Gawl) Miers. (Bignoniaceae), has been traditionally used as a remedy for treating white patches and infections on the skin (leukoderma, vitiligo). To investigate wound healing and antimicrobial activity of flower extract of Pyrostegia venusta, including in vivo antioxidant activity. Methanolic extracts of Pyrostegia venusta flowers were studied for wound healing efficiency along with its effect on pro-inflammatory and anti-inflammatory cytokines was assessed using excision and incision model of wound repair in Wistar rats. Healing was assessed by the rate of wound contraction, tensile strength, breaking strength, hydroxyproline and hexosamine content. Antimicrobial activity of the flower extract against twelve microorganisms was also assessed. In vivo antioxidant activity was performed to understand the mechanism of wound healing potency. The results indicated that Pyrostegia venusta extract has potent wound healing capacity as evident from the wound contraction and increased tensile strength. Hydroxyproline and hexosamine expression were also correlative with the healing pattern observed. Pyrostegia venusta extract exhibited moderate antimicrobial activity against the organisms: Bacillus subtilis, Staphylococcus epidermidis, Staphylococcus pyogenes, Staphylococcus aureus, Escherichia coli, Micrococcus luteus, Enterobacter aerogenes, Salmonella typhi, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger and Candida tropicana. During early wound healing phase TNF-α and IL-6 level were found to be up regulated by Pyrostegia venusta treatment. Increased wound contraction and tensile strength, augmented hydroxyproline and hexosamine content along with antioxidative activity and moderate antimicrobial activity support the early wound healing exhibited by Pyrostegia venusta flower extract. Induction in cytokine production may be one of the mechanisms involved in accelerating the wound healing by Pyrostegia venusta extract. Results suggest that Pyrostegia venusta may be useful in the tropical management of wound healing. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Mechanical Properties of Mg-Gd and Mg-Y Solid Solutions

NASA Astrophysics Data System (ADS)

Kula, Anna; Jia, Xiaohui; Mishra, Raj K.; Niewczas, Marek

2016-12-01

The mechanical properties of Mg-Gd and Mg-Y solid solutions have been studied under uniaxial tension and compression between 4 K and 298 K (-269 °C and 25 °C). The results reveal that Mg-Gd alloys exhibit higher strength and ductility under tension and compression attributed to the more effective solid solution strengthening and grain-boundary strengthening effects. Profuse twinning has been observed under compression, resulting in a material texture with strong dominance of basal component parallel to compression axis. Under tension, twining is less active and the texture evolution is controlled mostly by slip. The alloys exhibit pronounced yield stress asymmetry and significantly different work-hardening behavior under tension and compression. Increasing of Gd and/or Y concentration leads to the reduction of the tension-compression asymmetry due to the weakening of the recrystallization texture and more balanced twinning and slip activity during plastic deformation. The results suggest that under compression of Mg-Y alloys slip is more active than twinning in comparison to Mg-Gd alloys.

Rottlerin upregulates DDX3 expression in hepatocellular carcinoma.

PubMed

Wang, Zhong; Shen, Gen-Hai; Xie, Jia-Ming; Li, Bin; Gao, Quan-Gen

2018-01-01

Rottlerin has been reported to exert its anti-tumor activity in various types of human cancers. However, the underlying molecular mechanism has not been fully elucidated. In the current study, we explored whether rottlerin exhibits its tumor suppressive function in hepatocellular carcinoma cells. Our MTT assay results showed that rottlerin inhibited cell growth in hepatocellular carcinoma cells. Moreover, we found that rottlerin induced cell apoptosis and caused cell cycle arrest at G1 phase. Furthermore, our wound healing assay result demonstrated that rottlerin retarded cell migration in hepatocellular carcinoma cells. Additionally, rottlerin suppressed cell migration and invasion. Notably, we found that rottlerin upregulated DDX3 expression and subsequently downregulated Cyclin D1 expression and increased p21 level. Importantly, down-regulation of DDX3 abrogated the rottlerin-mediated tumor suppressive function, whereas overexpression of DDX3 promoted the anti-tumor activity of rottlerin. Our study suggests that rottlerin exhibits its anti-cancer activity partly due to upregulation of DDX3 in hepatocellular carcinoma cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Reduction-responsive multifunctional hyperbranched polyaminoglycosides with excellent antibacterial activity, biocompatibility and gene transfection capability.

PubMed

Huang, Yajun; Ding, Xiaokang; Qi, Yu; Yu, Bingran; Xu, Fu-Jian

2016-11-01

There is an increasing demand in developing of multifunctional materials with good antibacterial activity, biocompatibility and drug/gene delivery capability for next-generation biomedical applications. To achieve this purpose, in this work series of hydroxyl-rich hyperbranched polyaminoglycosides of gentamicin, tobramycin, and neomycin (HP and SS-HP with redox-responsive disulfide bonds) were readily synthesized via ring-opening reactions in a one-pot manner. Both HP and SS-HP exhibit high antibacterial activity toward Escherichia coli and Staphylococcus aureus. Meanwhile, the hemolysis assay of the above materials shows good biocompatibility. Moreover, SS-HPs show excellent gene transfection efficiency in vitro due to the breakdown of reduction-responsive disulfide bonds. For an in vivo anti-tumor assay, the SS-HP/p53 complexes exhibit potent inhibition capability to the growth of tumors. This study provides a promising approach for the design of next-generation multifunctional biomedical materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elucidation of the Oxygen Reduction Volcano in Alkaline Media using a Copper-Platinum(111) Alloy.

PubMed

Jensen, Kim D; Tymoczko, Jakub; Rossmeisl, Jan; Bandarenka, Aliaksandr S; Chorkendorff, Ib; Escudero-Escribano, María; Stephens, Ifan E L

2018-03-05

The relationship between the binding of the reaction intermediates and oxygen reduction activity in alkaline media was experimentally explored. By introducing Cu into the 2nd surface layer of a Pt(111) single crystal, the surface reactivity was tuned. In both 0.1 m NaOH and 0.1 m KOH, the optimal catalyst should exhibit OH binding circa 0.1 eV weaker than Pt(111), via a Sabatier volcano; this observation suggests that the reaction is mediated via the same surface bound intermediates as in acid, in contrast to previous reports. In 0.1 m KOH, the alloy catalyst at the peak of the volcano exhibits a maximum activity of 101±8 mA cm -2 at 0.9 V vs. a reversible hydrogen electrode (RHE). This activity constitutes a circa 60-fold increase over Pt(111) in 0.1 m HClO 4 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Berberine, a natural product, combined with cisplatin enhanced apoptosis through a mitochondria/caspase-mediated pathway in HeLa cells.

PubMed

Youn, Myung-Ja; So, Hong-Seob; Cho, Hea-Joong; Kim, Hyung-Jin; Kim, Yunha; Lee, Jeong-Han; Sohn, Jung Sook; Kim, Yong Kyu; Chung, Sang-Young; Park, Raekil

2008-05-01

Berberine, a main component of Coptidis Rhizoma, has been extensively studied and is known to exhibit multiple pharmacologic activities. In this study, we investigated whether the combination of berberine and cisplatin exhibited significant cytotoxicity in HeLa cells. Apoptosis was evaluated based on DNA fragmentation and cytofluorometrically with the annexin-V/propidium iodide labeling method. Combined treatment with berberine and cisplatin acted in concert to induce loss of mitochondrial membrane potential (Delta Psi m), release of cytochrome-c from mitochondria, and decreased expression of antiapoptotic Bcl-2, Bcl-x/L, resulting in activation of caspases and apoptosis. Further study showed that cell death induced by the combined treatment was associated with increased reactive oxygen species generation and lipid peroxidation. Moreover, we discovered that the combined treatment-induced apoptosis was mediated by the activation of the caspase cascade. These results indicated that the potential of cytotoxicity mediated through the mitochondria-caspase pathway is primarily involved in the combined treatment-induced apoptosis.

[Effects of nootropic drugs on behavior of BALB/c and C57BL/6 mice in the exploratory cross-maze test].

PubMed

Vasil'eva, E V; Salimov, R M; Kovalev, G I

2012-01-01

Exploratory behavior, locomotor activity, and anxiety in inbred mice of C57BL/6 and BALB/c strains subchronically treated with placebo or various types of nootropic (cognition enhancing) drugs (piracetam, phenotropil, noopept, semax, pantogam, nooglutil) have been evaluated using the exploratory cross-maze test. It was found that BALB/c mice in comparison to C57BL/6 mice are characterized by greater anxiety and lower efficiency of exploratory behavior in the previously unfamiliar environment. All tested drugs clearly improved the exploratory behavior in BALB/c mice only. In BALB/c mice, piracetam, phenotropil, noopept, and semax also reduced anxiety, while phenotropil additionally increased locomotor activity. Thus, the nootropic drugs displayed clear positive modulation of spontaneous orientation in the mice strain with initially low exploratory efficiency (BALB/c) in the cross-maze test. Some drugs (pantogam, nooglutil) exhibited only nootropic properties, while the other drugs exhibited both nootropic effects on the exploratory activity and produced modulation of the anxiety level (piracetam, fenotropil, noopept, semax) and locomotor activity (fenotropil).

Novel Trisubstituted Benzimidazoles, Targeting Mtb FtsZ, As A New Class of Antitubercular Agents

PubMed Central

Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Zanardi, Ilaria; Ruzsicska, Bela; Knudson, Susan; Tonge, Peter J.; Slayden, Richard A.; Ojima, Iwao

2010-01-01

Libraries of novel trisubstituted benzimidazoles were created through rational drug design. A good number of these benzimidazoles exhibited promising MIC values in the range of 0.5-6 μg/mL (2-15 μM) for their antibacterial activity against Mtb H37Rv strain. Moreover, five of the lead compounds also exhibited excellent activity against clinical Mtb strains with different drug-resistance profiles. All lead compounds do not show appreciable cytotoxicity (IC50 >200 μM) against Vero cells, which inhibit Mtb FtsZ assembly in a dose dependent manner. The two lead compounds unexpectedly showed enhancement of the GTPase activity of Mtb FtsZ. The result strongly suggests that the increased GTPase activity destabilizes FtsZ assembly leading to efficient inhibition of FtsZ polymerization and filament formation. The TEM and SEM analyses of Mtb FtsZ and Mtb cells, respectively, treated with a lead compound strongly suggest that lead benzimidazoles have a novel mechanism of action on the inhibition of Mtb FtsZ assembly and Z-ring formation. PMID:21126020

Novel trisubstituted benzimidazoles, targeting Mtb FtsZ, as a new class of antitubercular agents.

PubMed

Kumar, Kunal; Awasthi, Divya; Lee, Seung-Yub; Zanardi, Ilaria; Ruzsicska, Bela; Knudson, Susan; Tonge, Peter J; Slayden, Richard A; Ojima, Iwao

2011-01-13

Libraries of novel trisubstituted benzimidazoles were created through rational drug design. A good number of these benzimidazoles exhibited promising MIC values in the range of 0.5-6 μg/mL (2-15 μM) for their antibacterial activity against Mtb H37Rv strain. Moreover, five of the lead compounds also exhibited excellent activity against clinical Mtb strains with different drug-resistance profiles. All lead compounds did not show appreciable cytotoxicity (IC(50) > 200 μM) against Vero cells, which inhibited Mtb FtsZ assembly in a dose dependent manner. The two lead compounds unexpectedly showed enhancement of the GTPase activity of Mtb FtsZ. The result strongly suggests that the increased GTPase activity destabilizes FtsZ assembly, leading to efficient inhibition of FtsZ polymerization and filament formation. The TEM and SEM analyses of Mtb FtsZ and Mtb cells, respectively, treated with a lead compound strongly suggest that lead benzimidazoles have a novel mechanism of action on the inhibition of Mtb FtsZ assembly and Z-ring formation.

Production and physicochemical properties of recombinant Lactobacillus plantarum tannase.

PubMed

Curiel, José Antonio; Rodríguez, Héctor; Acebrón, Iván; Mancheño, José Miguel; De Las Rivas, Blanca; Muñoz, Rosario

2009-07-22

Tannase is an enzyme with important biotechnological applications in the food industry. Previous studies have identified the tannase encoding gene in Lactobacillus plantarum and also have reported the description of the purification of recombinant L. plantarum tannase through a protocol involving several chromatographic steps. Here, we describe the high-yield production of pure recombinant tannase (17 mg/L) by a one-step affinity procedure. The purified recombinant tannase exhibits optimal activity at pH 7 and 40 degrees C. Addition of Ca(2+) to the reaction mixture greatly increased tannase activity. The enzymatic activity of tannase was assayed against 18 simple phenolic acid esters. Only esters derived from gallic acid and protocatechuic acid were hydrolyzed. In addition, tannase activity was also assayed against the tannins tannic acid, gallocatechin gallate, and epigallocatechin gallate. Despite L. plantarum tannase representing a novel family of tannases, which shows no significant similarity to tannases from fungal sources, both families of enzymes shared similar substrate specificity range. The physicochemical characteristics exhibited by L. plantarum recombinant tannase make it an adequate alternative to the currently used fungal tannases.

Piezo1 links mechanical forces to red blood cell volume

PubMed Central

Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

2015-01-01

Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis. DOI: http://dx.doi.org/10.7554/eLife.07370.001 PMID:26001274

Hyaluronan- and heparin-reduced silver nanoparticles with antimicrobial properties

PubMed Central

Kemp, Melissa M; Kumar, Ashavani; Clement, Dylan; Ajayan, Pulickel; Mousa, Shaker

2009-01-01

Aims Silver nanoparticles exhibit unique antibacterial properties that make these ideal candidates for biological and medical applications. We utilized a clean method involving a single synthetic step to prepare silver nanoparticles that exhibit antimicrobial activity. Materials & methods These nanoparticles were prepared by reducing silver nitrate with diaminopyridinylated heparin (DAPHP) and hyaluronan (HA) polysaccharides and tested for their efficacy in inhibiting microbial growth. Results & discussion The resulting silver nanoparticles exhibit potent antimicrobial activity against Staphylococcus aureus and modest activity against Escherichia coli. Silver–HA showed greater antimicrobial activity than silver–DAPHP, while silver–glucose nanoparticles exhibited very weak antimicrobial activity. Neither HA nor DAPHP showed activity against S. aureus or E. coli. Conclusion These results suggest that DAPHP and HA silver nanoparticles have potential in antimicrobial therapeutic applications. PMID:19505245

Phenotypic plasticity of sun and shade ecotypes of Stellaria longipes in response to light quality signaling, gibberellins and auxin.

PubMed

Kurepin, Leonid V; Pharis, Richard P; Neil Emery, R J; Reid, David M; Chinnappa, C C

2015-09-01

Stellaria longipes plant communities (ecotypes) occur in several environmentally distinct habitats along the eastern slopes of southern Alberta's Rocky Mountains. One ecotype occurs in a prairie habitat at ∼1000 m elevation where Stellaria plants grow in an environment in which the light is filtered by taller neighbouring vegetation, i.e. sunlight with a low red to far-red (R/FR) ratio. This ecotype exhibits a high degree of phenotypic plasticity by increasing stem elongation in response to the low R/FR ratio light signal. Another Stellaria ecotype occurs nearby at ∼2400 m elevation in a much cooler alpine habitat, one where plants rarely experience low R/FR ratio shade light. Stem elongation of plants is largely regulated by gibberellins (GAs) and auxin, indole-3-acetic acid (IAA). Shoots of the prairie ecotype plants show increased IAA levels under low R/FR ratio light and they also increase their stem growth in response to applied IAA. The alpine ecotype plants show neither response. Plants from both ecotypes produce high levels of growth-active GA1 under low R/FR ratio light, though they differ appreciably in their catabolism of GA1. The alpine ecotype plants exhibit very high levels of GA8, the inactive product of GA1 metabolism, under both normal and low R/FR ratio light. Alpine origin plants may de-activate GA1 by conversion to GA8 via a constitutively high level of expression of the GA2ox gene, thereby maintaining their dwarf phenotype and exhibiting a reduced phenotypic plasticity in terms of shoot elongation. In contrast, prairie plants exhibit a high degree of phenotypic plasticity, using low R/FR ratio light-mediated changes in GA and IAA concentrations to increase shoot elongation, thereby accessing direct sunlight to optimize photosynthesis. There thus appear to be complex adaptation strategies for the two ecotypes, ones which involve modifications in the homeostasis of endogenous hormones. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

The impact of professional development in informal science contexts on teachers' content knowledge and discourse

NASA Astrophysics Data System (ADS)

Holliday, Gary M.

The Contextual Model of Learning (CML; Falk & Dierking, 1992, 2000) and reform documents have emphasized the unique learning environments that ISIs provide and the social aspects of that learning. As a result, individuals are able to use "each other as vehicles for reinforcing beliefs and meaning making" (Kisiel, 2003, p. 3). This study looked at two science content courses that were taught over two years by education staff of a large science and technology museum located in the Midwest. Data from six courses, with 187 participating elementary and middle school teachers, included content tests, portfolios and graduate credit assignments, daily and final evaluations of the course, as well as audio and video recordings of teachers while they were interacting with exhibits or engaged in an exhibit related activity. Results of this study found that PD educators' use of exhibits during both courses did not fully take into account the sociocultural context of CML and did not incorporate opportunities for discourse into the course instruction. However, when PD staff did make explicit connections between exhibits, science content, and activities, participants were more likely to be involved in in-depth, content related and pedagogical conversations while engaged in the courses. At the same time, even though teachers were very satisfied with the courses and felt that PD staff was effective in their instruction, participating teachers did not increase their science content knowledge even when explicit content connections were made to exhibits. It was unclear what outcomes the PD educators expect or want for their teacher students other than relaying content in a didactic manner (which was a secondary concern), sparking an interest in science, and providing many hands-on activities to bring back to the classroom. There is a need for a standardized professional development program for ISI educators and a need for restructuring ISI professional development so that it will address elementary and middle school teachers' need for science content. Further, developing instructional strategies for informal sites will be important since the learning potential that can be found through exhibits and exhibitions are not being fully realized.

Ribonucleic Acid Synthesis by Cucumber Chromatin

PubMed Central

Johnson, Kenneth D.; Purves, William K.

1970-01-01

When intact etiolated 2-day cucumber (Cucumis sativus) embryos were treated with indoleacetic acid (IAA), gibberellin A7 (GA7), or kinetin, chromatin derived from the embryonic axes exhibited an increased capacity to support RNA synthesis in either the presence or the absence of bacterial RNA polymerase. An IAA effect on cucumber RNA polymerase activity was evident after 4 hours of hormone treatment; the IAA effect on DNA template activity (bacterial RNA polymerase added) occurred after longer treatments (12 hours). GA7 also promoted template activity, but again only after a prior stimulation of endogenous chromatin activity. After 12 hours of kinetin treatment, both endogenous chromatin and DNA template activities were substantially above control values, but longer kinetin treatments caused these activities to decline in magnitude. When chromatin was prepared from hypocotyl segments that were floated on a GA7 solution, a GA-induced increase in endogenous chromatin activity occurred, but only if cotyledon tissue was left attached to the segments during the period of hormone treatment. Age of the seedling tissue had a profound influence on the chromatin characteristics. With progression of development from the 2-day to the 4-day stage, the endogenous chromatin activity declined while the DNA template activity increased. PMID:16657509

Cortical Plasticity Following Motor Skill Learning During Mental Practice in Stroke1

PubMed Central

Page, Stephen J.; Szaflarski, Jerzy P.; Eliassen, James C.; Pan, Hai; Cramer, Steven C

2012-01-01

Background and Purpose Mental practice (MP), which involves cognitive rehearsal of physical movements, is a non-invasive, inexpensive method of enabling repetitive, task specific practice (RTP). Recent, randomized controlled data suggest that MP, when combined with a RTP therapy program, increases affected arm use and function significantly more than RTP only. As a next step, this 10-subject case series examined the possibility that cortical plasticity is a mechanism underlying the treatment effect of MP when combined with RTP. Method 10 chronic stroke patients (mean = 36.7 months) exhibiting stable, moderate motor deficits received ½ hour therapy sessions for their affected arms, occurring 3 days/week for 10 weeks, and emphasizing valued activities of daily living (ADLs). Directly after therapy, subjects received 30-minute MP sessions, which required MP of the ADLs performed during therapy. Behavioral outcomes were blindly evaluated using the Action Research Arm Test (ARAT) and the Fugl-Meyer Assessment (FM). Functional magnetic resonance imaging (fMRI) was administered before and after intervention to assess cortical changes. Results Before intervention, subjects exhibited stable motor deficits. After intervention, subjects exhibited marked ARAT and FM score increases (+ 5.3 and + 4.2, respectively), and clinically significant, new abilities to perform valued ADLs. Post-intervention fMRI revealed significant increases in activation to wrist flexion and extension of the affected hand in the premotor area and primary motor cortex ipsi- and contralaterally to the affected hand, and superior parietal cortex ipsilateral to the affected hand. Decreased activations were noted in parietal cortex of the hemisphere ipsilateral to the affected hand. These changes correlated with anatomical regions in which behavioral changes were observed via the ARAT and FM. Conclusions MP is an easy to use, cost effective strategy that was again shown to improve affected arm outcomes after stroke. This is the first study suggesting alteration in the cortical map as a possible MP mechanism for the affected arm. PMID:19155350

Hydrogen generation from water/methanol under visible light using aerogel prepared strontium titanate (SrTiO3) nanomaterials doped with ruthenium and rhodium metals

NASA Astrophysics Data System (ADS)

Kuo, Yenting; Klabunde, Kenneth J.

2012-07-01

Nanostructured strontium titanate visible-light-driven photocatalysts containing rhodium and ruthenium were synthesized by a modified aerogel synthesis using ruthenium chloride and rhodium nitrate as dopant precursors, and titanium isopropoxide and strontium metal as the metal sources. The well-defined crystalline SrTiO3 structure was confirmed by means of x-ray diffraction. After calcination at 500 °C, diffuse reflectance spectroscopy shows an increase in light absorption at 370 nm due to the presence of Rh3 + ; however an increase of the calcination temperature to 600 °C led to a decrease in intensity, probably due to a loss of surface area. An increase in the rhodium doping level also led to an increase in absorption at 370 nm however, the higher amounts of dopant lowered the photocatalytic activity. The modified aerogel synthesis allows greatly enhanced H2 production performance from an aqueous methanol solution under visible light irradiation compared with lower surface area conventional materials. We believe that this enhanced activity is due to the higher surface areas while high quality nanocrystalline materials are still obtained. Furthermore, the surface properties of these nanocrystalline aerogel materials are different, as exhibited by the higher activities in alkaline solutions, while conventional materials (obtained via high temperature solid-state synthesis methods) only exhibit reasonable hydrogen production in acidic solutions. Moreover, an aerogel synthesis approach gives the possibility of thin-film formation and ease of incorporation into practical solar devices.

Intracellular lipid dysregulation interferes with leukocyte function in the ovaries of meat-type hens under unrestricted feed intake.

PubMed

Liu, Zu-Chen; Su, Chia-Ming; Xie, Yi-Lun; Chang, Chai-Ju; Chen, Jiang-Young; Wu, Shu-Wei; Chen, Yu-Hui; Walzem, Rosemary L; Huang, San-Yuan; Chen, Shuen-Ei

2016-04-01

Meat-type Red-feather country hens fed ad libitum (AD-hens) exhibit obesity-associated morbidities and a number of ovarian irregularities. Leukocyte participations in ovarian activities are unstudied in AD-hens. In contrast to feed-restricted hens (R-hens), ovulatory process of the F1 follicle appeared delayed in AD-hens in association with reduced F1 follicle progesterone content, gelatinase A (MMP-2) and collagenase-3 (MMP-13) activities coincident with elevated IL-1β and no production (P<0.05), and increased leukocyte infiltration of inflamed necrotic follicle walls. Extracts of AD-hen F1 follicle walls induced greater leukocyte migration than extracts from F1 follicle wall extracts of R-hens (P<0.05). Co-cultures of granulosa cells with increasing numbers of leukocytes from either AD-hens or R-hens exhibited dose dependent reductions in progesterone production and increases in cell death. AD-hen leukocytes were less proapoptotic than their R counterparts (P<0.05). Granulosa MMP-13 and MMP-2 activities were also suppressed in the co-cultures with heterophils or monocytes in a dose-dependent manner (P<0.05). AD heterophils and R monocytes had a greater inhibitory effect on MMP activities in the co-cultures than their respective counterparts (P<0.05). Both basal and LPS-induced IL-1β secretion and MMP-22 or MMP-2 activities in freshly isolated AD-hen leukocytes were reduced (P<0.05). Exposure of AD or R leukocytes to 0.5mM palmitate impaired IL-1β secretion and MMP-22 or MMP-2 activity. Inhibition of ceramide synthesis with FB1 and ROS production with n-MPG scavenging rescued MMP activity and IL-1β production in palmitate treated heterophils, but exacerbated monocyte suppression. These latter findings suggest that intracellular lipid dysregulation in leukocytes contributes to ovarian dysfunction in AD-hens. Copyright © 2016 Elsevier B.V. All rights reserved.

The immunomodulatory activities of licorice polysaccharides (Glycyrrhiza uralensis Fisch.) in CT 26 tumor-bearing mice.

PubMed

Ayeka, Peter Amwoga; Bian, YuHong; Githaiga, Peter Mwitari; Zhao, Ying

2017-12-15

The increasing use of complementary and alternative medicine (CAM) has kindled the need for scientific evaluation of the mechanism of action of CAMs. Although, licorice, a common ingredient in many Traditional Chinese medicine (TCM) has attracted great attention for its antitumor and immunomodulatory activities, the mechanism of action of its polysaccharides is still unclear. Here we report the immunomodulatory activity of licorice polysaccharides in vivo. The differential anticancer activities of licorice polysaccharides by tumorigenesis and immunomodulation was evaluated in vivo. Six weeks old, 120 CT-26 tumor bearing BALB/c mice, weighing 20 ± 2 g were used. They were randomly divided into six groups, three groups receiving high molecular weight (fraction A), low molecular weight (fraction B) polysaccharides and crude extract (fraction C); positive, negative and normal groups receiving cytoxin, saline and normal diet respectively. Weight of mice and tumors was determined and tumorigenicity assay calculated to determine the anticancer effects. Immunomodulatory potential was determined by immune organ indices, immune cell population and serum cytokine levels using immune organ weight and index, flow cytometry and cytokine/chemokine bead panel kit respectively. Licorice polysaccharides exhibited immunomodulatory activities in CT 26 tumor bearing BALB/c mice. The polysaccharides significantly suppressed tumor growth and increased immune organ index. Furthermore, the immunomodulatory effect was evident with activation of CD4 + and CD8 + immune cells population. The polysaccharides also affected the production of various cytokines, by increasing IL 2, IL 6, IL 7 levels and a decreasing TNFα levels. In summary, licorice polysaccharide especially of low molecular weight exhibit anticancer and immunomodulatory activities by suppressing tumor growth and improving general health of mice. They also augment the thymus/spleen index and population of T lymphocytes. Furthermore, the polysaccharides enhance the levels of serum antitumor cytokines, IL 2, IL 6 and IL 7 while decreasing pro-tumor cytokine TNFα.

Induction of Direct or Priming Resistance against Botrytis cinerea in Strawberries by β-Aminobutyric Acid and Their Effects on Sucrose Metabolism.

PubMed

Wang, Kaituo; Liao, Yunxia; Xiong, Qi; Kan, Jianquan; Cao, Shifeng; Zheng, Yonghua

2016-07-27

The specific forms of disease resistance induced by β-aminobutyric acid (BABA) and their impacts on sucrose metabolism of postharvest strawberries were determined in the present research. Treatment with 10-500 mmol L(-1) BABA inhibited the Botrytis cinerea infection, possibly directly by suppressing the fungus growth and indirectly by triggering disease resistance. Moreover, BABA-induced resistance against B. cinerea infection in strawberries was associated with either one of two mechanisms, depending upon the concentration used: BABA at concentrations higher than 100 mmol L(-1) directly induced the defense response, including a H2O2 burst, modulation of the expression of PR genes, including FaPR1, FaChi3, Faβglu, and FaPAL, and increased activities of chitinase, β-1,3-glucanase, and PAL, whereas BABA at 10 mmol L(-1) activated a priming response because the BABA-treated fruits exhibited an increased capacity to express molecular defense only when the fruits were inoculated with B. cinerea. Activation of the priming defense appeared almost as effective against B. cinerea as inducing direct defense. However, the primed strawberries maintained higher activities of SS synthesis and SPS and SPP enzymes) and lower level of SS cleavage during the incubation; these activities contributed to higher sucrose, fructose, and glucose contents, sweetness index, and sensory scores compared to fruits exhibiting the direct defense. Thus, it is plausible that the priming defense, which can be activated by BABA at relatively low concentrations, represents an optimal strategy for combining the advantages of enhanced disease protection and soluble sugar accumulation.

Effect of active sensitization on the bronchopulmonary responses to tachykinins in the guinea pig. Modulation by peptidase inhibitors.

PubMed

Capaz, F R; Ruffié, C; Lefort, J; Manzini, S; Vargaftig, B B; Pretolani, M

1993-08-01

The i.v. administration of substance P (SP, 0.25-16 micrograms/kg) or of the selective metabolic stable NK-1 agonist, [Glp6,Pro9]SP-(6-11) (septide, 0.03-0.25 microgram) to atropine-treated guinea pigs or to isolated perfused lungs triggered a dose-dependent bronchoconstriction, which was enhanced in animals actively sensitized to ovalbumin. In vivo, bronchial hyper-responsiveness was restricted to SP and to septide, inasmuch as neurokinin A (0.06-1 microgram/kg)- or capsaicin (0.5-32 micrograms/kg)-induced bronchoconstriction were not modified. In contrast, isolated lungs from sensitized guinea pigs exhibited an increased bronchoconstriction also in response to capsaicin (0.01-10 micrograms), which was inhibited by atropine in the medium. Pretreatment of actively sensitized guinea pigs either with indomethacin plus mepyramine, the lipoxygenase inhibitor BW A4C or with the platelet-activating factor antagonist SR 27417, did not modify bronchial hyper-reactivity to SP. Captopril (5 mg/kg i.v.), but not thiorphan (0.8 mg/kg i.v.), increased the SP-induced bronchoconstriction in actively sensitized animals, whereas both inhibitors were equally effective in nonsensitized guinea pigs. Thiorphan, however, did not modify the in vivo response to septide. Our results demonstrate that guinea pigs sensitized to ovalbumin exhibit bronchial hyperreactivity to SP, but not to neurokinin A, as compared to nonsensitized animals, suggesting a decrease in the neutral endopeptidase activity in the airways brought by the immunization. However, the results obtained by using septide indicate that other mechanisms may be involved in the bronchial hyper-reactivity to SP.

Phase synchrony reveals organization in human atrial fibrillation

PubMed Central

Vidmar, David; Narayan, Sanjiv M.

2015-01-01

It remains unclear if human atrial fibrillation (AF) is spatially nonhierarchical or exhibits a hierarchy of organization sustained by sources. We utilize activation times obtained at discrete locations during AF to compute the phase synchrony between tissue regions, to examine underlying spatial dynamics throughout both atria. We construct a binary synchronization network and show that this network can accurately define regions of coherence in coarse-grained in silico data. Specifically, domains controlled by spiral waves exhibit regions of high phase synchrony. We then apply this analysis to clinical data from patients experiencing cardiac arrhythmias using multielectrode catheters to simultaneously record from a majority of both atria. We show that pharmaceutical intervention with ibutilide organizes activation by increasing the size of the synchronized domain in AF and quantify the increase in temporal organization when arrhythmia changes from fibrillation to tachycardia. Finally, in recordings from 24 patients in AF we show that the level of synchrony is spatially broad with some patients showing large spatially contiguous regions of synchronization, while in others synchrony is localized to small pockets. Using computer simulations, we show that this distribution is inconsistent with distributions obtained from simulations that mimic multiwavelet reentry but is consistent with mechanisms in which one or more spatially conserved spiral waves is surrounded by tissue in which activation is disorganized. PMID:26475585

Electronic Properties of Cyclacenes from TAO-DFT

PubMed Central

Wu, Chun-Shian; Lee, Pei-Yin; Chai, Jeng-Da

2016-01-01

Owing to the presence of strong static correlation effects, accurate prediction of the electronic properties (e.g., the singlet-triplet energy gaps, vertical ionization potentials, vertical electron affinities, fundamental gaps, symmetrized von Neumann entropy, active orbital occupation numbers, and real-space representation of active orbitals) of cyclacenes with n fused benzene rings (n = 4–100) has posed a great challenge to traditional electronic structure methods. To meet the challenge, we study these properties using our newly developed thermally-assisted-occupation density functional theory (TAO-DFT), a very efficient method for the study of large systems with strong static correlation effects. Besides, to examine the role of cyclic topology, the electronic properties of cyclacenes are also compared with those of acenes. Similar to acenes, the ground states of cyclacenes are singlets for all the cases studied. In contrast to acenes, the electronic properties of cyclacenes, however, exhibit oscillatory behavior (for n ≤ 30) in the approach to the corresponding properties of acenes with increasing number of benzene rings. On the basis of the calculated orbitals and their occupation numbers, the larger cyclacenes are shown to exhibit increasing polyradical character in their ground states, with the active orbitals being mainly localized at the peripheral carbon atoms. PMID:27853249

Gestational diabetes induces alterations in the function of neonatal endothelial colony-forming cells.

PubMed

Blue, Emily K; DiGiuseppe, Robert; Derr-Yellin, Ethel; Acosta, Juan Carlos; Pay, S Louise; Hanenberg, Helmut; Schellinger, Megan M; Quinney, Sara K; Mund, Julie A; Case, Jamie; Haneline, Laura S

2014-02-01

Children born to mothers with gestational diabetes mellitus (GDM) experience increased risk of developing hypertension, type 2 diabetes mellitus, and obesity. Disrupted function of endothelial colony-forming cells (ECFCs) may contribute to this enhanced risk. The goal of this study was to determine whether cord blood ECFCs from GDM pregnancies exhibit altered functionality. ECFCs isolated from the cord blood of control and GDM pregnancies were assessed for proliferation, senescence, and Matrigel network formation. The requirement for p38MAPK in hyperglycemia-induced senescence was determined using inhibition and overexpression studies. GDM-exposed ECFCs were more proliferative than control ECFCs. However, GDM-exposed ECFCs exhibited decreased network-forming ability in Matrigel. Aging of ECFCs by serial passaging led to increased senescence and reduced proliferation of GDM-exposed ECFCs. ECFCs from GDM pregnancies were resistant to hyperglycemia-induced senescence compared with those from controls. In response to hyperglycemia, control ECFCs activated p38MAPK, which was required for hyperglycemia-induced senescence. In contrast, GDM-exposed ECFCs showed no change in p38MAPK activation under equivalent conditions. Intrauterine exposure of ECFCs to GDM induces unique phenotypic alterations. The resistance of GDM-exposed ECFCs to hyperglycemia-induced senescence and decreased p38MAPK activation suggest that these progenitor cells have undergone changes that induce tolerance to a hyperglycemic environment.

Blast-Induced Tinnitus and Elevated Central Auditory and Limbic Activity in Rats: A Manganese-Enhanced MRI and Behavioral Study.

PubMed

Ouyang, Jessica; Pace, Edward; Lepczyk, Laura; Kaufman, Michael; Zhang, Jessica; Perrine, Shane A; Zhang, Jinsheng

2017-07-07

Blast-induced tinitus is the number one service-connected disability that currently affects military personnel and veterans. To elucidate its underlying mechanisms, we subjected 13 Sprague Dawley adult rats to unilateral 14 psi blast exposure to induce tinnitus and measured auditory and limbic brain activity using manganese-enhanced MRI (MEMRI). Tinnitus was evaluated with a gap detection acoustic startle reflex paradigm, while hearing status was assessed with prepulse inhibition (PPI) and auditory brainstem responses (ABRs). Both anxiety and cognitive functioning were assessed using elevated plus maze and Morris water maze, respectively. Five weeks after blast exposure, 8 of the 13 blasted rats exhibited chronic tinnitus. While acoustic PPI remained intact and ABR thresholds recovered, the ABR wave P1-N1 amplitude reduction persisted in all blast-exposed rats. No differences in spatial cognition were observed, but blasted rats as a whole exhibited increased anxiety. MEMRI data revealed a bilateral increase in activity along the auditory pathway and in certain limbic regions of rats with tinnitus compared to age-matched controls. Taken together, our data suggest that while blast-induced tinnitus may play a role in auditory and limbic hyperactivity, the non-auditory effects of blast and potential traumatic brain injury may also exert an effect.

Core-Shell ZIF-8@ZIF-67-Derived CoP Nanoparticle-Embedded N-Doped Carbon Nanotube Hollow Polyhedron for Efficient Overall Water Splitting.

PubMed

Pan, Yuan; Sun, Kaian; Liu, Shoujie; Cao, Xing; Wu, Konglin; Cheong, Weng-Chon; Chen, Zheng; Wang, Yu; Li, Yang; Liu, Yunqi; Wang, Dingsheng; Peng, Qing; Chen, Chen; Li, Yadong

2018-02-21

The construction of highly active and stable non-noble-metal electrocatalysts for hydrogen and oxygen evolution reactions is a major challenge for overall water splitting. Herein, we report a novel hybrid nanostructure with CoP nanoparticles (NPs) embedded in a N-doped carbon nanotube hollow polyhedron (NCNHP) through a pyrolysis-oxidation-phosphidation strategy derived from core-shell ZIF-8@ZIF-67. Benefiting from the synergistic effects between highly active CoP NPs and NCNHP, the CoP/NCNHP hybrid exhibited outstanding bifunctional electrocatalytic performances. When the CoP/NCNHP was employed as both the anode and cathode for overall water splitting, a potential as low as 1.64 V was needed to achieve the current density of 10 mA·cm -2 , and it still exhibited superior activity after continuously working for 36 h with nearly negligible decay in potential. Density functional theory calculations indicated that the electron transfer from NCNHP to CoP could increase the electronic states of the Co d-orbital around the Fermi level, which could increase the binding strength with H and therefore improve the electrocatalytic performance. The strong stability is attributed to high oxidation resistance of the CoP surface protected by the NCNHP.

NRP1 knockdown promotes the migration and invasion of human neuroblastoma-derived SK‑N‑AS cells via the activation of β1 integrin expression.

PubMed

Ishizuka, Yoshiaki; Koshinaga, Tsugumichi; Hirano, Takayuki; Nagasaki-Maeoka, Eri; Watanabe, Yosuke; Hoshi, Reina; Yoshizawa, Shinsuke; Sugito, Kiminobu; Kawashima, Hiroyuki; Uekusa, Shota; Fukuda, Noboru; Soma, Masayoshi; Fujiwara, Kyoko

2018-07-01

Neuropilin 1 (NRP1) is a transmembrane glycoprotein, which regulates many aspects of cellular function by functioning as co-receptor of various ligands. Recent studies have suggested that NRP1 promotes tumorigenesis, not only by activating the growth of tumor vessels, but also by activating the growth or migration of tumor cells themselves. The present study was performed to elucidate the roles of NRP1 in the development and/or progression of neuroblastoma (NB). In contrast to previous observations in various types of cancer, the analysis of public datasets indicated that lower levels of NRP1 expression were significantly associated with a shorter survival period of patients with NB. Consistent with this finding, wound-healing assay and Matrigel invasion assay revealed that NB cells in which NRP1 was knocked down exhibited increased migratory and invasive abilities. Further analyses indicated that β1 integrin expression was markedly increased in NB cells in which NRP1 was knocked down, and NB cells in which β1 integrin was knocked down exhibited decreased migratory and invasive abilities. The results presented herein indicate that NRP1 exerts tumor suppressive effects in NB, at least in part by regulating the expression of β1 integrin.

Application of sound and temperature to control boundary-layer transition

NASA Technical Reports Server (NTRS)

Maestrello, Lucio; Parikh, Paresh; Bayliss, A.; Huang, L. S.; Bryant, T. D.

1987-01-01

The growth and decay of a wave packet convecting in a boundary layer over a concave-convex surface and its active control by localized surface heating are studied numerically using direct computations of the Navier-Stokes equations. The resulting sound radiations are computed using linearized Euler equations with the pressure from the Navier-Stokes solution as a time-dependent boundary condition. It is shown that on the concave portion the amplitude of the wave packet increases and its bandwidth broadens while on the convex portion some of the components in the packet are stabilized. The pressure field decays exponentially away from the surface and then algebraically, exhibiting a decay characteristic of acoustic waves in two dimensions. The far-field acoustic behavior exhibits a super-directivity type of behavior with a beaming downstream. Active control by surface heating is shown to reduce the growth of the wave packet but have little effect on acoustic far field behavior for the cases considered. Active control by sound emanating from the surface of an airfoil in the vicinity of the leading edge is experimentally investigated. The purpose is to control the separated region at high angles of attack. The results show that injection of sound at shedding frequency of the flow is effective in an increase of lift and reduction of drag.

Musa paradisica RCI complements AtRCI and confers Na+ tolerance and K+ sensitivity in Arabidopsis.

PubMed

Liu, Bing; Feng, Dongru; Zhang, Bipei; Mu, Peiqiang; Zhang, Yang; He, Yanming; Qi, Kangbiao; Wang, Jinfa; Wang, Hongbin

2012-03-01

The mechanisms involved in Na⁺/K⁺ uptake and extrusion are important in plant salt tolerance. In this study, we investigated the physiological role of a plasma membrane (PM)-localized protein, MpRCI, from plantain in transgenic Arabidopsis under NaCl and KCl stress and determined its effect on PM fluidity and H⁺-ATPase activity. The MpRCI gene exhibited high homology to the AtRCI2 gene family in Arabidopsis and was therefore able to complement for loss of the yeast AtRCI2-related PMP3 gene. Results of phenotypic espial and atomic emission spectrophotometer (AES) assays indicated that MpRCI overexpression in the AtRCI2A knockout mutant with reduced shoot Na⁺ and increased K⁺ exhibited increased Na⁺-tolerance and K⁺-sensitivity under NaCl or KCl treatments, respectively. Furthermore, comparisons of PM fluidity and H⁺-ATPase activity in shoots, with expression or absence of MpRCI/AtRCI2A expression under NaCl or KCl stress, showed MpRCI maintained PM fluidity and H⁺-ATPase activity under stress conditions. Results suggest that MpRCI plays an essential role in Na⁺/K⁺ flux in plant cells. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The use of synthetic and natural vitamin D sources in pig diets to improve meat quality and vitamin D content.

PubMed

Duffy, Sarah K; Kelly, Alan K; Rajauria, Gaurav; Jakobsen, Jette; Clarke, Louise C; Monahan, Frank J; Dowling, Kirsten G; Hull, George; Galvin, Karen; Cashman, Kevin D; Hayes, Aoife; O'Doherty, John V

2018-09-01

This study investigated the effects of synthetic and natural sources of vitamin D biofortification in pig diets on pork vitamin D activity and pork quality. One hundred and twenty pigs (60 male, 60 female) were assigned to one of four dietary treatments for a 55 d feeding period. The dietary treatments were (1)50 μg vitamin D₃/kg of feed; (2)50 μg of 25-hydroxvitamin D₃/kg of feed (25-OH-D₃); (3)50 μg vitamin D₂/kg of feed; (4)50 μg vitamin D₂-enriched mushrooms/kg of feed (Mushroom D₂). The pigs offered the 25-OH-D₃ diet exhibited the highest (P < 0.001) serum total 25-hydroxyvitamin D concentration and subsequently exhibited the highest (P < 0.05) Longissimus thoracis (LT) total vitamin D activity. Mushroom D 2 and 25-OH-D 3 supplementation increased pork antioxidant status. The vitamin D₂-enriched mushrooms improved (P < 0.05) pig performance, carcass weight and LT colour. In conclusion, 25-OH-D₃ is the most successful source for increasing pork vitamin D activity, while Mushroom D 2 may be a new avenue to improve animal performance and pork quality. Copyright © 2018 Elsevier Ltd. All rights reserved.

Silencing and heterologous expression of ppo-2 indicate a specific function of a single polyphenol oxidase isoform in resistance of dandelion (Taraxacum officinale) against Pseudomonas syringae pv. tomato.

PubMed

Richter, Carolin; Dirks, Mareike E; Gronover, Christian Schulze; Prüfer, Dirk; Moerschbacher, Bruno M

2012-02-01

Dandelion (Taraxacum officinale) possesses an unusually high degree of disease resistance. As this plant exhibits high polyphenol oxidase (PPO) activity and PPO have been implicated in resistance against pests and pathogens, we analyzed the potential involvement of five PPO isoenzymes in the resistance of dandelion against Botrytis cinerea and Pseudomonas syringae pv. tomato. Only one PPO (ppo-2) was induced during infection, and ppo-2 promoter and β-glucuronidase marker gene fusions revealed strong induction of the gene surrounding lesions induced by B. cinerea. Specific RNAi silencing reduced ppo-2 expression only, and concomitantly increased plant susceptibility to P. syringae pv. tomato. At 4 days postinoculation, P. syringae pv. tomato populations were strongly increased in the ppo-2 RNAi lines compared with wild-type plants. When the dandelion ppo-2 gene was expressed in Arabidopsis thaliana, a plant having no PPO gene, active protein was formed and protein extracts of the transgenic plants exhibited substrate-dependent antimicrobial activity against P. syringae pv. tomato. These results clearly indicate a strong contribution of a specific, single PPO isoform to disease resistance. Therefore, we propose that specific PPO isoenzymes be included in a new family of pathogenesis-related (PR) proteins.

Identification of a Novel Hypocholesterolemic Protein, Major Royal Jelly Protein 1, Derived from Royal Jelly

PubMed Central

Asai, Saori; Kusada, Mio; Watanabe, Suzuyo; Kawashima, Takuji; Nakamura, Tadashi; Shimada, Masaya; Goto, Tsuyoshi; Nagaoka, Satoshi

2014-01-01

Royal jelly (RJ) intake lowers serum cholesterol levels in animals and humans, but the active component in RJ that lowers serum cholesterol level and its molecular mechanism are unclear. In this study, we set out to identify the bile acid-binding protein contained in RJ, because dietary bile acid-binding proteins including soybean protein and its peptide are effective in ameliorating hypercholesterolemia. Using a cholic acid-conjugated column, we separated some bile acid-binding proteins from RJ and identified the major RJ protein 1 (MRJP1), MRJP2, and MRJP3 as novel bile acid-binding proteins from RJ, based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Purified MRJP1, which is the most abundant protein of the bile acid-binding proteins in RJ, exhibited taurocholate-binding activity in vitro. The micellar solubility of cholesterol was significantly decreased in the presence of MRJP1 compared with casein in vitro. Liver bile acids levels were significantly increased, and cholesterol 7α-hydroxylase (CYP7A1) mRNA and protein tended to increase by MRJP1 feeding compared with the control. CYP7A1 mRNA and protein levels were significantly increased by MRJP1 tryptic hydrolysate treatment compared with that of casein tryptic hydrolysate in hepatocytes. MRJP1 hypocholesterolemic effect has been investigated in rats. The cholesterol-lowering action induced by MRJP1 occurs because MRJP1 interacts with bile acids induces a significant increase in fecal bile acids excretion and a tendency to increase in fecal cholesterol excretion and also enhances the hepatic cholesterol catabolism. We have identified, for the first time, a novel hypocholesterolemic protein, MRJP1, in RJ. Interestingly, MRJP1 exhibits greater hypocholesterolemic activity than the medicine β-sitosterol in rats. PMID:25144734

Quantification of Kinetic Rate Law Parameters of Uranium Release from Sodium Autunite as a Function of Aqueous Bicarbonate Concentrations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gudavalli, Ravi; Katsenovich, Yelena; Wellman, Dawn M.

2013-09-05

ABSTRACT: Hydrogen carbonate is one of the most significant components within the uranium geochemical cycle. In aqueous solutions, hydrogen carbonate forms strong complexes with uranium. As such, aqueous bicarbonate may significantly increase the rate of uranium release from uranium minerals. Quantifying the relationship of aqueous hydrogen carbonate solutions to the rate of uranium release during dissolution is critical to understanding the long-term fate of uranium within the environment. Single-pass flow-through (SPTF) experiments were conducted to estimate the rate of uranium release from Na meta-autunite as a function of bicarbonate solutions (0.0005-0.003 M) under the pH range of 6-11 and temperaturesmore » of 5-60oC. Consistent with the results of previous investigation, the rate of uranium release from sodium autunite exhibited minimal dependency on temperature; but were strongly dependent on pH and increasing concentrations of bicarbonate solutions. Most notably at pH 7, the rate of uranium release exhibited 370 fold increases relative to the rate of uranium release in the absence of bicarbonate. However, the effect of increasing concentrations of bicarbonate solutions on the release of uranium was significantly less under higher pH conditions. It is postulated that at high pH values, surface sites are saturated with carbonate, thus the addition of more bicarbonate would have less effect on uranium release. Results indicate the activation energies were unaffected by temperature and bicarbonate concentration variations, but were strongly dependent on pH conditions. As pH increased from 6 to 11, activation energy values were observed to decrease from 29.94 kJ mol-1 to 13.07 kJ mol-1. The calculated activation energies suggest a surface controlled dissolution mechanism.« less

[Oxygen consumption rate and effects of hypoxia stress on enzyme activities of Sepiella maindron].

PubMed

Wang, Chun-lin; Wu, Dan-hua; Dong, Tian-ye; Jiang, Xia-min

2008-11-01

The oxygen consumption rate and suffocation point of Sepiella maindroni were determined through the measurement of dissolved oxygen in control and experimental respiration chambers by Winkler's method, and the changes of S. maindroni enzyme activities under different levels of hypoxia stress were studied. The results indicated that the oxygen consumption rate of S. maindroni exhibited an obvious diurnal fluctuation of 'up-down-up-down', and positively correlated with water temperature (16 degrees C-28 degrees C) and illumination (3-500 micromol x m(-2) x s(-1)) while negatively correlated with water pH (6.25-9.25). With increasing water salinity from 18.1 to 29.8, the oxygen consumption rate had a variation of 'up-down-up', being the lowest at salinity 24. 8. Female S. maindroni had a higher oxygen consumption rate than male S. maindroni. The suffocation point of S. maindroni decreased with its increasing body mass, and that of (38.70 +/- 0.52) g in mass was (0.9427 +/- 0.0318) mg x L(-1). With the increase of hypoxia stress, the activities of superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) decreased after an initial increase, lipase activity decreased, protease activity had a variation of 'decrease-increase-decrease', and lactate dehydrogenase (LDH) activity had a trend of increasing first and decreasing then. The enzyme activities were higher under hypoxia stress than under normal conditions.

Turmeric and black pepper spices decrease lipid peroxidation in meat patties during cooking.

PubMed

Zhang, Yanjun; Henning, Susanne M; Lee, Ru-Po; Huang, Jianjun; Zerlin, Alona; Li, Zhaoping; Heber, David

2015-05-01

Spices are rich in natural antioxidants and have been shown to be potent inhibitors of lipid peroxidation during cooking of meat. Turmeric contains unique conjugated curcuminoids with strong antioxidant activity. Piperine, one of the main constituents of black pepper, is known to increase the bioavailability of curcuminoids in mouse and human studies when consumed with turmeric. We investigated whether adding black pepper to turmeric powder may further inhibit lipid peroxidation when added to meat patties prior to cooking. The addition of black pepper to turmeric significantly decreased the lipid peroxidation in hamburger meat. When investigating the antioxidant activity of the main chemical markers, we determined that piperine did not exhibit any antioxidant activity. Therefore, we conclude that other black pepper ingredients are responsible for the increased antioxidant activity of combining black pepper with turmeric powder.

Turmeric and black pepper spices decrease lipid peroxidation in meat patties during cooking

PubMed Central

Zhang, Yanjun; Henning, Susanne M.; Lee, Ru-Po; Huang, Jianjun; Zerlin, Alona; Li, Zhaoping; Heber, David

2015-01-01

Abstract Spices are rich in natural antioxidants and have been shown to be potent inhibitors of lipid peroxidation during cooking of meat. Turmeric contains unique conjugated curcuminoids with strong antioxidant activity. Piperine, one of the main constituents of black pepper, is known to increase the bioavailability of curcuminoids in mouse and human studies when consumed with turmeric. We investigated whether adding black pepper to turmeric powder may further inhibit lipid peroxidation when added to meat patties prior to cooking. The addition of black pepper to turmeric significantly decreased the lipid peroxidation in hamburger meat. When investigating the antioxidant activity of the main chemical markers, we determined that piperine did not exhibit any antioxidant activity. Therefore, we conclude that other black pepper ingredients are responsible for the increased antioxidant activity of combining black pepper with turmeric powder. PMID:25582173

Antecedent occipital alpha band activity predicts the impact of oculomotor events in perceptual switching

PubMed Central

Nakatani, Hironori; van Leeuwen, Cees

2013-01-01

Oculomotor events such as blinks and saccades transiently interrupt the visual input and, even though this mostly goes undetected, these brief interruptions could still influence the percept. In particular, both blinking and saccades facilitate switching in ambiguous figures such as the Necker cube. To investigate the neural state antecedent to these oculomotor events during the perception of an ambiguous figure, we measured the human scalp electroencephalogram (EEG). When blinking led to perceptual switching, antecedent occipital alpha band activity exhibited a transient increase in amplitude. When a saccade led to switching, a series of transient increases and decreases in amplitude was observed in the antecedent occipital alpha band activity. Our results suggest that the state of occipital alpha band activity predicts the impact of oculomotor events on the percept. PMID:23745106

Hydrocarbon-stapled lipopeptides exhibit selective antimicrobial activity.

PubMed

Jenner, Zachary B; Crittenden, Christopher M; Gonzalez, Martín; Brodbelt, Jennifer S; Bruns, Kerry A

2017-05-01

Antimicrobial peptides (AMPs) occur widely in nature and have been studied for their therapeutic potential. AMPs are of interest due to the large number of possible chemical structural combinations using natural and unnatural amino acids, with varying effects on their biological activities. Using physicochemical properties from known naturally occurring amphipathic cationic AMPs, several hydrocarbon-stapled lipopeptides (HSLPs) were designed, synthesized, and tested for antimicrobial properties. Peptides were chemically modified by N-terminal acylation, C-terminal amidation, and some were hydrocarbon stapled by intramolecular olefin metathesis. The effects of peptide length, amphipathic character, and stapling on antimicrobial activity were tested against Escherichia coli, three species of Gram-positive bacteria (Staphylococcus aureus, Bacillus megaterium, and Enterococcus faecalis), and two strains of Candida albicans. Peptides were shown to disrupt liposomes of different phospholipid composition, as measured by leakage of a fluorescent compound from vesicles. Peptides with (S)-2-(4'-pentenyl)-alanine substituted for l-alanine in a reference peptide showed a marked increase in antimicrobial activity, hemolysis, and membrane disruption. Stapled peptides exhibited slightly higher antimicrobial potency; those with greatest hydrophobic character showed the greatest hemolysis and liposome leakage, but lower antimicrobial activity. The results support a model of HSLPs as membrane-disruptive AMPs with potent antimicrobial activity and relatively low hemolytic potential at biologically active peptide concentrations. © 2017 Wiley Periodicals, Inc.

Highly porous activated carbons from resource-recovered Leucaena leucocephala wood as capacitive deionization electrodes.

PubMed

Hou, Chia-Hung; Liu, Nei-Ling; Hsi, Hsing-Cheng

2015-12-01

Highly porous activated carbons were resource-recovered from Leucaena leucocephala (Lam.) de Wit. wood through combined chemical and physical activation (i.e., KOH etching followed by CO2 activation). This invasive species, which has severely damaged the ecological economics of Taiwan, was used as the precursor for producing high-quality carbonaceous electrodes for capacitive deionization (CDI). Carbonization and activation conditions strongly influenced the structure of chars and activated carbons. The total surface area and pore volume of activated carbons increased with increasing KOH/char ratio and activation time. Overgasification induced a substantial amount of mesopores in the activated carbons. In addition, the electrochemical properties and CDI electrosorptive performance of the activated carbons were evaluated; cyclic voltammetry and galvanostatic charge/discharge measurements revealed a typical capacitive behavior and electrical double layer formation, confirming ion electrosorption in the porous structure. The activated-carbon electrode, which possessed high surface area and both mesopores and micropores, exhibited improved capacitor characteristics and high electrosorptive performance. Highly porous activated carbons derived from waste L. leucocephala were demonstrated to be suitable CDI electrode materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

Neural control of renal function.

PubMed

Johns, Edward J; Kopp, Ulla C; DiBona, Gerald F

2011-04-01

The kidney is innervated with efferent sympathetic nerve fibers that directly contact the vasculature, the renal tubules, and the juxtaglomerular granular cells. Via specific adrenoceptors, increased efferent renal sympathetic nerve activity decreases renal blood flow and glomerular filtration rate, increases renal tubular sodium and water reabsorption, and increases renin release. Decreased efferent renal sympathetic nerve activity produces opposite functional responses. This integrated system contributes importantly to homeostatic regulation of sodium and water balance under physiological conditions and to pathological alterations in sodium and water balance in disease. The kidney contains afferent sensory nerve fibers that are located primarily in the renal pelvic wall where they sense stretch. Stretch activation of these afferent sensory nerve fibers elicits an inhibitory renorenal reflex response wherein the contralateral kidney exhibits a compensatory natriuresis and diuresis due to diminished efferent renal sympathetic nerve activity. The renorenal reflex coordinates the excretory function of the two kidneys so as to facilitate homeostatic regulation of sodium and water balance. There is a negative feedback loop in which efferent renal sympathetic nerve activity facilitates increases in afferent renal nerve activity that in turn inhibit efferent renal sympathetic nerve activity so as to avoid excess renal sodium retention. In states of renal disease or injury, there is activation of afferent sensory nerve fibers that are excitatory, leading to increased peripheral sympathetic nerve activity, vasoconstriction, and increased arterial pressure. Proof of principle studies in essential hypertensive patients demonstrate that renal denervation produces sustained decreases in arterial pressure. © 2011 American Physiological Society. Compr Physiol 1:699-729, 2011.

TRAIL-CM4 fusion protein shows in vitro antibacterial activity and a stronger antitumor activity than solo TRAIL protein.

PubMed

Sang, Ming; Zhang, Jiaxin; Li, Bin; Chen, Yuqing

2016-06-01

A TRAIL-CM4 fusion protein in soluble form with tumor selective apoptosis and antibacterial functions was expressed in the Escherichia coli expression system and isolated through dialysis refolding and histidine-tag Nickel-affinity purification. Fresh Jurkat cells were treated with the TRAIL-CM4 fusion protein. Trypan blue staining and MTT analyses showed that, similar to a TRAIL positive control, Jurkat cell proliferation was significantly inhibited. Flow cytometry analyses using Annexin V-fluorescein revealed that Jurkat cells treated with the TRAIL-CM4 fusion protein exhibited increased apoptosis. Laser confocal microscopy showed that APB-CM4 and the fusion protein TRAIL-CM4 can bind to Jurkat cell membranes and initiate their destruction. ABP-CM4 enhances the antitumor activity of TRAIL by targeting and damaging the tumor cell membrane. In antibacterial experiments, agar well diffusion and bacterial growth inhibition curve assays revealed concentration-dependent TRAIL-CM4 antibacterial activity against Escherichia coli K12D31. The expressed TRAIL-CM4 fusion protein exhibited enhanced antitumor and antibacterial activities. Fusion protein expression allowed the two different proteins to function in combination. Copyright © 2016 Elsevier Inc. All rights reserved.

Tracing the pH dependent activation of autophagy in cancer cells by silicon nanowire-based impedance biosensor.

PubMed

Alikhani, Alireza; Gharooni, Milad; Abiri, Hamed; Farokhmanesh, Fatemeh; Abdolahad, Mohammad

2018-05-30

Monitoring the pH dependent behavior of normal and cancer cells by impedimetric biosensor based on Silicon Nanowires (SiNWs) was introduced to diagnose the invasive cancer cells. Autophagy as a biologically activated process in invasive cancer cells during acidosis, protect them from apoptosis in lower pH which presented in our work. As the autophagy is the only activated pathways which can maintain cellular proliferation in acidic media, responses of SiNW-ECIS in acidified cells could be correlated to the probability of autophagy activation in normal or cancer cells. In contrast, cell survival pathway wasn't activated in low-grade cancer cells which resulted in their acidosis. The measured electrical resistance of MCF10, MCF7, and MDA-MB468 cell lines, by SiNW sensor, in normal and acidic media were matched by the biological analyses of their vital functions. Invasive cancer cells exhibited increased electrical resistance in pH 6.5 meanwhile the two other types of the breast cells exhibited sharp (MCF10) and moderate (MCF7) decrease in their resistance. This procedure would be a new trend in microenvironment based cancer investigation. Copyright © 2018 Elsevier B.V. All rights reserved.

Dimensionality and entropy of spontaneous and evoked rate activity

NASA Astrophysics Data System (ADS)

Engelken, Rainer; Wolf, Fred

Cortical circuits exhibit complex activity patterns both spontaneously and evoked by external stimuli. Finding low-dimensional structure in population activity is a challenge. What is the diversity of the collective neural activity and how is it affected by an external stimulus? Using concepts from ergodic theory, we calculate the attractor dimensionality and dynamical entropy production of these networks. We obtain these two canonical measures of the collective network dynamics from the full set of Lyapunov exponents. We consider a randomly-wired firing-rate network that exhibits chaotic rate fluctuations for sufficiently strong synaptic weights. We show that dynamical entropy scales logarithmically with synaptic coupling strength, while the attractor dimensionality saturates. Thus, despite the increasing uncertainty, the diversity of collective activity saturates for strong coupling. We find that a time-varying external stimulus drastically reduces both entropy and dimensionality. Finally, we analytically approximate the full Lyapunov spectrum in several limiting cases by random matrix theory. Our study opens a novel avenue to characterize the complex dynamics of rate networks and the geometric structure of the corresponding high-dimensional chaotic attractor. received funding from Evangelisches Studienwerk Villigst, DFG through CRC 889 and Volkswagen Foundation.

Apigenin exhibits protective effects in a mouse model of d-galactose-induced aging via activating the Nrf2 pathway.

PubMed

Sang, Ying; Zhang, Fan; Wang, Heng; Yao, Jianqiao; Chen, Ruichuan; Zhou, Zhengdao; Yang, Kun; Xie, Yan; Wan, Tianfeng; Ding, Hong

2017-06-21

The aim of the present research was to study the protective effects and underlying mechanisms of apigenin on d-galactose-induced aging mice. Firstly, apigenin exhibited a potent antioxidant activity in vitro. Secondly, d-galactose was administered by subcutaneous injection once daily for 8 weeks to establish an aging mouse model to investigate the protective effect of apigenin. We found that apigenin supplementation significantly ameliorated aging-related changes such as behavioral impairment, decreased organic index, histopathological injury, increased senescence-associated β-galactosidase (SAβ-gal) activity and advanced glycation end product (AGE) level. Further data showed that apigenin facilitated Nrf2 nuclear translocation both in aging mice and normal young mice, and the Nrf2 expression of normal young mice was higher than that of natural senile mice. In addition, the expressions of Nrf2 downstream gene targets, including HO-1 and NQO1, were also promoted by apigenin administration. Moreover, apigenin also decreased the MDA level and elevated SOD and CAT activities. In conclusion, focusing on the Nrf2 pathway is a suitable strategy to delay the aging process, and apigenin may exert an anti-senescent effect process via activating the Nrf2 pathway.

Patterning of sympathetic nerve activity in response to vestibular stimulation

NASA Technical Reports Server (NTRS)

Kerman, I. A.; McAllen, R. M.; Yates, B. J.

2000-01-01

Growing evidence suggests a role for the vestibular system in regulation of autonomic outflow during postural adjustments. In the present paper we review evidence for the patterning of sympathetic nerve activity elicited by vestibular stimulation. In response to electrical activation of vestibular afferents, firing of sympathetic nerves located throughout the body is altered. However, activity of the renal nerve is most sensitive to vestibular inputs. In contrast, high-intensity simultaneous activation of cutaneous and muscle inputs elicits equivalent changes in firing of the renal, superior mesenteric and lumbar colonic nerves. Responses of muscle vasoconstrictor (MVC) efferents to vestibular stimulation are either inhibitory (Type I) or are comprised of a combination of excitation and inhibition (Type II). Interestingly, single MVC units located in the hindlimb exhibited predominantly Type I responses while those located in the forelimb and face exhibited Type II responses. Furthermore, brachial and femoral arterial blood flows were dissociated in response to vestibular stimulation, such that brachial vascular resistance increased while femoral resistance decreased. These studies demonstrate that vestibulosympathetic reflexes are patterned according to both the anatomical location and innervation target of a particular sympathetic nerve, and can lead to distinct changes in local blood flow.

Synthesis and biological evaluation of new berberine derivatives as cancer immunotherapy agents through targeting IDO1.

PubMed

Wang, Yan-Xiang; Pang, Wei-Qiang; Zeng, Qing-Xuan; Deng, Zhe-Song; Fan, Tian-Yun; Jiang, Jian-Dong; Deng, Hong-Bin; Song, Dan-Qing

2018-01-01

To discover small-molecule cancer immunotherapy candidates through targeting Indoleamine 2,3-dioxygenase 1 (IDO1), twenty-five new berberine (BBR) derivatives defined with substituents on position 3 or 9 were synthesized and examined for repression of IFN-γ-induced IDO1 promoter activities. Structure-activity relationship (SAR) indicated that large volume groups at the 9-position might be beneficial for potency. Among them, compounds 2f, 2i, 2n, 2o and 8b exhibited increased activities, with inhibition rate of 71-90% compared with BBR. Their effects on IDO1 expression were further confirmed by protein level as well. Furthermore, compounds 2i and 2n exhibited anticancer activity by enhancing the specific lysis of NK cells to A549 through IDO1, but not cytotoxicity. Preliminary mechanism revealed that both of them inhibited IFN-γ-induced IDO1 expression through activating AMPK and subsequent inhibition of STAT1 phosphorylation. Therefore, compounds 2i and 2n have been selected as IDO1 modulators for small-molecule cancer immunotherapy for next investigation. Copyright © 2017 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

Antiplasmodial Activity of [(Aryl)arylsulfanylmethyl]Pyridine▿ †‡

PubMed Central

Kumar, Sanjay; Das, Sajal Kumar; Dey, Sumanta; Maity, Pallab; Guha, Mithu; Choubey, Vinay; Panda, Gautam; Bandyopadhyay, Uday

2008-01-01

A series of [(aryl)arylsufanylmethyl]pyridines (AASMP) have been synthesized. These compounds inhibited hemozoin formation, formed complexes (KD = 12 to 20 μM) with free heme (ferriprotoporphyrin IX) at a pH close to the pH of the parasite food vacuole, and exhibited antimalarial activity in vitro. The inhibition of hemozoin formation may develop oxidative stress in Plasmodium falciparum due to the accumulation of free heme. Interestingly, AASMP developed oxidative stress in the parasite, as evident from the decreased level of glutathione and increased formation of lipid peroxide, H2O2, and hydroxyl radical (·OH) in P. falciparum. AASMP also caused mitochondrial dysfunction by decreasing mitochondrial potential (ΔΨm) in malaria parasite, as measured by both flow cytometry and fluorescence microscopy. Furthermore, the generation of ·OH may be mainly responsible for the antimalarial effect of AASMP since ·OH scavengers such as mannitol, as well as spin trap α-phenyl-n-tertbutylnitrone, significantly protected P. falciparum from AASMP-mediated growth inhibition. Cytotoxicity testing of the active compounds showed selective activity against malaria parasite with selectivity indices greater than 100. AASMP also exhibited profound antimalarial activity in vivo against chloroquine resistant P. yoelii. Thus, AASMP represents a novel class of antimalarial. PMID:18025110

Antiproliferative and pro-apoptotic effects of three fungal exocellular β-glucans in MCF-7 breast cancer cells is mediated by oxidative stress, AMP-activated protein kinase (AMPK) and the Forkhead transcription factor, FOXO3a.

PubMed

Queiroz, Eveline A I F; Fortes, Zuleica B; da Cunha, Mário A A; Barbosa, Aneli M; Khaper, Neelam; Dekker, Robert F H

2015-10-01

Fungal β-d-glucans of the (1→3)-type are known to exhibit direct antitumor effects, and can also indirectly decrease tumor proliferation through immunomodulatory responses. The underlying molecular mechanisms involved in decreasing tumor formation, however, are not well understood. In this study, we examined the antiproliferative role and mechanism of action of three different fungal exocellular β-glucans in MCF-7 breast cancer cells. The β-glucans were obtained from Botryosphaeria rhodina MAMB-05 [two botryosphaerans; (1→3)(1→6)-β-d-glucan; one produced on glucose, the other on fructose] and Lasiodiplodia theobromae MMPI [lasiodiplodan; (1→6)-β-d-glucan, produced on glucose]. Using the cell proliferation-MTT assay, we showed that the β-glucans exhibited a time- and concentration-dependent antiproliferative activity (IC50, 100μg/ml). Markers of cell cycle, apoptosis, necrosis and oxidative stress were analyzed using flow cytometry, RT-PCR and Western blotting. Exposure to β-glucans increased apoptosis, necrosis, oxidative stress, mRNA expression of p53, p27 and Bax; the activity of AMP-activated protein-kinase, Forkhead transcription factor FOXO3a, Bax and caspase-3; and decreased the activity of p70S6K in MCF-7 cells. In the presence of hydrogen peroxide, the fungal β-glucans increased oxidative stress, which was associated with reduced cell viability. We showed that these β-glucans exhibited an antiproliferative effect that was associated with apoptosis, necrosis and oxidative stress. This study demonstrated for the first time that the apoptosis induced by β-glucans was mediated by AMP-activated protein-kinase and Forkhead transcription factor, FOXO3a. Our findings provide novel mechanistic insights into their antiproliferative roles, and compelling evidence that these β-glucans possess a broad range of biomodulatory properties that may prove useful in cancer treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Putative PAX8/PPARγ Fusion Oncoprotein Exhibits Partial Tumor Suppressor Activity through Up-Regulation of Micro-RNA-122 and Dominant-Negative PPARγ Activity.

PubMed

Reddi, Honey V; Madde, Pranathi; Milosevic, Dragana; Hackbarth, Jennifer S; Algeciras-Schimnich, Alicia; McIver, Bryan; Grebe, Stefan K G; Eberhardt, Norman L

2011-01-01

In vitro studies have demonstrated that the PAX8/PPARγ fusion protein (PPFP), which occurs frequently in follicular thyroid carcinomas (FTC), exhibits oncogenic activity. However, paradoxically, a meta-analysis of extant tumor outcome studies indicates that 68% of FTC-expressing PPFP are minimally invasive compared to only 32% of those lacking PPFP (χ(2) = 6.86, P = 0.008), suggesting that PPFP favorably impacts FTC outcomes. In studies designed to distinguish benign thyroid neoplasms from thyroid carcinomas, the previously identified tumor suppressor miR-122, a major liver micro-RNA (miR) that is decreased in hepatocellular carcinoma, was increased 8.9-fold (P < 0.05) in all FTC versus normal, 9.2-fold in FTC versus FA (P < 0.05), and 16.8-fold (P < 0.001) in FTC + PPFP versus FTC - PPFP. Constitutive expression of PPFP in the FTC-derived cell line WRO (WRO-PPFP) caused a 5-fold increase of miR-122 expression (P < 0.05) and a striking 5.1-fold reduction (P < 0.0001) in tumor progression compared to WRO-vector cells in a mouse xenograft model. Constitutive expression of either miR-122 or a dominant-negative PPARγ mutant in WRO cells was less effective than PPFP at inhibiting xenograft tumor progression (1.8-fold [P < 0.001] and 1.7-fold [P < 0.03], respectively). PPFP-induced up-regulation of miR-122 expression was independent of its known dominant-negative PPARγ activity. Up-regulation of miR-122 negatively regulates ADAM-17, a known downstream target, in thyroid cells, suggesting an antiangiogenic mechanism in thyroid carcinoma. This latter inference is directly supported by reduced CD-31 expression in WRO xenografts expressing PPFP, miR-122, and DN-PPARγ. We conclude that, in addition to its apparent oncogenic potential in vitro, PPFP exhibits paradoxical tumor suppressor activity in vivo, mediated by multiple mechanisms including up-regulation of miR-122 and dominant-negative inhibition of PPARγ activity.

Development of the Methane Hydrate Burning Experimental Equipment

NASA Astrophysics Data System (ADS)

Aoyama, S.

2010-12-01

There is a need to increase understanding among Japanese citizens about the importance as a potential future energy source of the great quantity of methane hydrate deposits sleeping on the sea bed around Japan. With cooperation from the Japan Oil, Gas and Metals National Corporation (JOGMEC), the National Institute of Advanced Industrial Science and Technology (AIST), and the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) we studied the possibility of using presentations where it was possible to handle actual methane hydrate, videos and active presentations such as experiments in order to increase the public interest in and understanding of methane hydrate. Furthermore, for the benefit of those people who would like to visit the exhibition but are unable to do so due to distance or other physical barriers, we looked into making the presentation materials portable and having a moving exhibition. Currently methane hydrate combustion experiments and exhibition performances are being held at the Hidaka Port New Energy Park (The Kansai Electric Power Co., Inc.) in Gobo, Wakayama with approximately 3,000 visitors monthly.

Engineering electrocatalytic activity in nanosized perovskite cobaltite through surface spin-state transition

PubMed Central

Zhou, Shiming; Miao, Xianbing; Zhao, Xu; Ma, Chao; Qiu, Yuhao; Hu, Zhenpeng; Zhao, Jiyin; Shi, Lei; Zeng, Jie

2016-01-01

The activity of electrocatalysts exhibits a strongly dependence on their electronic structures. Specifically, for perovskite oxides, Shao-Horn and co-workers have reported a correlation between the oxygen evolution reaction activity and the eg orbital occupation of transition-metal ions, which provides guidelines for the design of highly active catalysts. Here we demonstrate a facile method to engineer the eg filling of perovskite cobaltite LaCoO3 for improving the oxygen evolution reaction activity. By reducing the particle size to ∼80 nm, the eg filling of cobalt ions is successfully increased from unity to near the optimal configuration of 1.2 expected by Shao-Horn's principle. Consequently, the activity is significantly enhanced, comparable to those of recently reported cobalt oxides with eg∼1.2 configurations. This enhancement is ascribed to the emergence of spin-state transition from low-spin to high-spin states for cobalt ions at the surface of the nanoparticles, leading to more active sites with increased reactivity. PMID:27187067

Glycometabolic adaptation mediates the insensitivity of drug-resistant K562/ADM leukaemia cells to adriamycin via the AKT-mTOR/c-Myc signalling pathway.

PubMed

Zhang, Xueyan; Ai, Ziying; Chen, Jing; Yi, Juan; Liu, Zhuan; Zhao, Huaishun; Wei, Hulai

2017-04-01

In human leukaemia, resistance to chemotherapy leads to treatment ineffectiveness or failure. Previous studies have indicated that cancers with increased levels of aerobic glycolysis are insensitive to numerous forms of chemotherapy and respond poorly to radiotherapy. Whether glycolysis serves a key role in drug resistance of leukaemia cells remains unclear. The present study systematically investigated aerobic glycolytic alterations and regulation in K562/adriamycin (ADM) multidrug‑resistant (MDR) and ADM‑sensitive K562 leukaemia cells in normoxia, and the association between drug resistance and improper glycometabolism. The cell proliferating activity was assessed with an MTT colorimetric assay, glycolysis, including glucose consumption, lactate export and key‑enzyme activity was determined by corresponding commercial testing kits. The expression levels of hexokinase‑II (HK‑II), lactate dehydrogenase A (LDHA), glucose transporter‑4 (GLUT‑4), AKT, p‑AKT473/308, mammalian target of rapamycin (mTOR), p‑mTOR, c‑Myc and hypoxia‑inducible factor‑1α (HIF‑1α) were analyzed by western blot or reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). K562/ADM cells exhibited increased glucose consumption and lactate accumulation, increased lactate dehydrogenase, hexokinase and pyruvate kinase activities, and reduced phosphofructokinase activity. In addition, K562/ADM cells expressed significantly more HK‑II and GLUT‑4. Notably, inhibition of glycolysis effectively killed sensitive and resistant leukaemia cells and potently restored the sensitivity of MDR cells to the anticancer agent ADM. The AKT serine/threonine kinase (AKT)/mechanistic target of rapamycin (mTOR) signalling pathway, a crucial regulator of glycometabolic homeostasis, mediated over‑activation and upregulation of c‑Myc expression levels in K562/ADM cells, which directly stimulated glucose consumption and enhanced glycolysis. In conclusion, the present study demonstrated that MDR leukaemia cells exhibit increased aerobic glycolytic activity and that this may be responsible for resistance to chemotherapeutics in leukaemia MDR cells via activation of the AKT‑mTOR‑c‑Myc signalling pathway. Therefore, inhibition of aerobic glycolysis may be a potential therapeutic strategy to efficiently treat multidrug resistance in relapsed or refractory leukaemia and cancers.

Evidence Suggesting that the Cardiomyocyte Circadian Clock Modulates Responsiveness of the Heart to Hypertrophic Stimuli in Mice

PubMed Central

Durgan, David J.; Tsai, Ju-Yun; Grenett, Maximiliano H.; Pat, Betty M.; Ratcliffe, William F.; Villegas-Montoya, Carolina; Garvey, Merissa E.; Nagendran, Jeevan; Dyck, Jason R.B.; Bray, Molly S.; Gamble, Karen L.; Gimble, Jeffrey M.; Young, Martin E.

2011-01-01

Circadian dyssynchrony of an organism (at the whole body level) with its environment, either through light/dark cycle or genetic manipulation of clock genes, augments various cardiometabolic diseases. The cardiomyocyte circadian clock has recently been shown to influence multiple myocardial processes, ranging from transcriptional regulation and energy metabolism, to contractile function. We therefore reasoned that chronic dyssychrony of the cardiomyocyte circadian clock with its environment would precipitate myocardial maladaptation to a circadian challenge (simulated shift work; SSW). To test this hypothesis, 2 and 20 month old wild-type and CCM (Cardiomyocyte Clock Mutant; a model with genetic temporal suspension of the cardiomyocyte circadian clock at the active-to-sleep phase transition) mice were subjected to chronic (16-wks) bi-weekly 12-hr phase shifts in the light/dark cycle (i.e., SSW). Assessment of adaptation/maladaptation at whole body homeostatic, gravimetric, humoral, histological, transcriptional, and cardiac contractile function levels revealed essentially identical responses between wild-type and CCM littermates. However, CCM hearts exhibit increased bi-ventricular weight, cardiomyocyte size, and molecular markers of hypertrophy (anf, mcip1) independent of aging and/or SSW. Similarly, a second genetic model of selective temporal suspension of the cardiomyocyte circadian clock (Cardiomyocyte-specific BMAL1 Knockout [CBK] mice) exhibits increased bi-ventricular weight and mcip1 expression. Wild-type mice exhibit 5-fold greater cardiac hypertrophic growth (and 6-fold greater anf mRNA induction) when challenged with the hypertrophic agonist isoproterenol at the active-to-sleep phase transition, relative to isoproterenol administration at the sleep-to-active phase transition. This diurnal variation was absent in CCM mice. Collectively, these data suggest that the cardiomyocyte circadian clock likely influences responsiveness of the heart to hypertrophic stimuli. PMID:21452915

Systemic hyperfibrinolysis after trauma: a pilot study of targeted proteomic analysis of superposed mechanisms in patient plasma.

PubMed

Banerjee, Anirban; Silliman, Christopher C; Moore, Ernest E; Dzieciatkowska, Monika; Kelher, Marguerite; Sauaia, Angela; Jones, Kenneth; Chapman, Michael P; Gonzalez, Eduardo; Moore, Hunter B; D'Alessandro, Angelo; Peltz, Erik; Huebner, Benjamin E; Einerson, Peter; Chandler, James; Ghasabayan, Arsen; Hansen, Kirk

2018-06-01

Viscoelastic measurements of hemostasis indicate that 20% of seriously injured patients exhibit systemic hyperfibrinolysis, with increased early mortality. These patients have normal clot formation with rapid clot lysis. Targeted proteomics was applied to quantify plasma proteins from hyperfibrinolytic (HF) patients to elucidate potential pathophysiology. Blood samples were collected in the field or at emergency department arrival and thrombelastography (TEG) was used to characterize in vitro clot formation under native and tissue plasminogen activator (tPA)-stimulated conditions. Ten samples were taken from injured patients exhibiting normal lysis time at 30 min (Ly30), "eufibrinolytic" (EF), 10 from HF patients, defined as tPA-stimulated TEG Ly30 >50%, and 10 from healthy controls. Trauma patient samples were analyzed by targeted proteomics and ELISA assays for specific coagulation proteins. HF patients exhibited increased plasminogen activation. Thirty-three proteins from the HF patients were significantly decreased compared with healthy controls and EF patients; 17 were coagulation proteins with anti-protease consumption (p < 0.005). The other 16 decreased proteins indicate activation of the alternate complement pathway, depletion of carrier proteins, and four glycoproteins. CXC7 was elevated in all injured patients versus healthy controls (p < 0.005), and 35 proteins were unchanged across all groups (p > 0.1 and fold change of concentrations of 0.75-1.3). HF patients had significant decreases in specific proteins and support mechanisms known in trauma-induced hyperfibrinolysis and also unexpected decreases in coagulation factors, factors II, X, and XIII, without changes in clot formation (SP, R times, or angle). Decreased clot stability in HF patients was corroborated with tPA-stimulated TEGs. Prognostic, level III.

Metabolic evolution of two reducing equivalent-conserving pathways for high-yield succinate production in Escherichia coli.

PubMed

Zhu, Xinna; Tan, Zaigao; Xu, Hongtao; Chen, Jing; Tang, Jinlei; Zhang, Xueli

2014-07-01

Reducing equivalents are an important cofactor for efficient synthesis of target products. During metabolic evolution to improve succinate production in Escherichia coli strains, two reducing equivalent-conserving pathways were activated to increase succinate yield. The sensitivity of pyruvate dehydrogenase to NADH inhibition was eliminated by three nucleotide mutations in the lpdA gene. Pyruvate dehydrogenase activity increased under anaerobic conditions, which provided additional NADH. The pentose phosphate pathway and transhydrogenase were activated by increased activities of transketolase and soluble transhydrogenase SthA. These data suggest that more carbon flux went through the pentose phosphate pathway, thus leading to production of more reducing equivalent in the form of NADPH, which was then converted to NADH through soluble transhydrogenase for succinate production. Reverse metabolic engineering was further performed in a parent strain, which was not metabolically evolved, to verify the effects of activating these two reducing equivalent-conserving pathways for improving succinate yield. Activating pyruvate dehydrogenase increased succinate yield from 1.12 to 1.31mol/mol, whereas activating the pentose phosphate pathway and transhydrogenase increased succinate yield from 1.12 to 1.33mol/mol. Activating these two pathways in combination led to a succinate yield of 1.5mol/mol (88% of theoretical maximum), suggesting that they exhibited a synergistic effect for improving succinate yield. Copyright © 2014 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

Thermal activation in Co/Sb nanoparticle-multilayer thin films

NASA Astrophysics Data System (ADS)

Madden, Michael R.

Multilayer "Co" /"Sb" thin films created via electron-beam physical vapor deposition are known to exhibit thermally activated dynamics. Scanning tunneling microscopy has indicated that the "Co" forms nanoparticles within an "Sb" matrix during deposition and subsequently forms nanowires by way of NP migration within the interstices of the confining layers. The electrical resistance of these systems decays during this irreversible aging process in a manner well-modeled by an Arrhenius law. Presently, this phenomenon is shown to possess some degree of tunability with respect to "Co" layer thickness tCo as well as deposition temperature Tdep , whereby characteristic timescales increase with either parameter. Furthermore, fluctuation timescales and activation energies seem to decrease and increase respectively with increasing t Co. An easily calibrated, one-time-use, time-temperature switch based on such systems lies within the realm of plausibility. The results presented here can be considered to be part of an ongoing development of the concept.

Context Memory Decline in Middle Aged Adults is Related to Changes in Prefrontal Cortex Function.

PubMed

Kwon, Diana; Maillet, David; Pasvanis, Stamatoula; Ankudowich, Elizabeth; Grady, Cheryl L; Rajah, M Natasha

2016-06-01

The ability to encode and retrieve spatial and temporal contextual details of episodic memories (context memory) begins to decline at midlife. In the current study, event-related fMRI was used to investigate the neural correlates of context memory decline in healthy middle aged adults (MA) compared with young adults (YA). Participants were scanned while performing easy and hard versions of spatial and temporal context memory tasks. Scans were obtained at encoding and retrieval. Significant reductions in context memory retrieval accuracy were observed in MA, compared with YA. The fMRI results revealed that overall, both groups exhibited similar patterns of brain activity in parahippocampal cortex, ventral occipito-temporal regions and prefrontal cortex (PFC) during encoding. In contrast, at retrieval, there were group differences in ventral occipito-temporal and PFC activity, due to these regions being more activated in MA, compared with YA. Furthermore, only in YA, increased encoding activity in ventrolateral PFC, and increased retrieval activity in occipital cortex, predicted increased retrieval accuracy. In MA, increased retrieval activity in anterior PFC predicted increased retrieval accuracy. These results suggest that there are changes in PFC contributions to context memory at midlife. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Pigeonpea Hybrid-Proline-Rich Protein (CcHyPRP) Confers Biotic and Abiotic Stress Tolerance in Transgenic Rice

PubMed Central

Mellacheruvu, Sunitha; Tamirisa, Srinath; Vudem, Dashavantha Reddy; Khareedu, Venkateswara Rao

2016-01-01

In this study, we report the overexpression of Cajanus cajan hybrid-proline-rich protein encoding gene (CcHyPRP) in rice which resulted in increased tolerance to both abiotic and biotic stresses. Compared to the control plants, the transgenic rice lines, expressing CcHyPRP, exhibited high-level tolerance against major abiotic stresses, viz., drought, salinity, and heat, as evidenced by increased biomass, chlorophyll content, survival rate, root, and shoot growth. Further, transgenic rice lines showed increased panicle size and grain number compared to the control plants under different stress conditions. The CcHyPRP transgenics, as compared to the control, revealed enhanced activities of catalase and superoxide dismutase (SOD) enzymes and reduced malondialdehyde (MDA) levels. Expression pattern of CcHyPRP::GFP fusion-protein confirmed its predominant localization in cell walls. Moreover, the CcHyPRP transgenics, as compared to the control, exhibited increased resistance to the fungal pathogen Magnaporthe grisea which causes blast disease in rice. Higher levels of bZIP and endochitinase transcripts as well as endochitinase activity were observed in transgenic rice compared to the control plants. The overall results demonstrate the intrinsic role of CcHyPRP in conferring multiple stress tolerance at the whole-plant level. The multipotent CcHyPRP seems promising as a prime candidate gene to fortify crop plants for enhanced tolerance/resistance to different stress factors. PMID:26834756

Phenolic acid concentrations in plasma and urine from men consuming green or black tea and potential chemopreventive properties for colon cancer

PubMed Central

Henning, Susanne M.; Wang, Piwen; Abgaryan, Narine; Vicinanza, Roberto; de Oliveira, Daniela Moura; Zhang, Yanjun; Lee, Ru-Po; Carpenter, Catherine L.; Aronson, William J.; Heber, David

2013-01-01

Scope Tea polyphenols are metabolized by the colonic microflora yielding phenolic metabolites, which may contribute to the health benefits of tea. We determined the serum and urine concentrations of phenolic acids, hippuric acid and polyhydroxyphenyl-γ-valerolactones during green tea (GT) and black tea (BT) administration. The effects of (−)-epigallocatechin gallate (EGCG) and 3,4-dihydroxyphenylacetic acid (3,4-DHPAA) alone and in combination on bioavailability, intracellular metabolism, and antiproliferative activity was determined in HCT-116 colon cancer cells. Methods and Results The concentration of phenolic metabolites was quantified by HPLC with electrochemical detection and MS. Urine concentrations of 4-hydroxyphenylacetic acid (4-HPAA), 3-hydroxyphenylacetic acid (3-HPAA) and polyhydroxy-γ-valerolactones were increased significantly in men drinking GT compared to control. Urine concentration of 3-O-methylgallic acid (3OMGA) was significantly increased in men drinking BT compared to control. Serum 3,4-DHPAA was significantly increased after consumption of GT and BT and 4-HPAA after GT consumption. In vitro treatment of HCT-116 colon cancer cells with 3,4-DHPAA and EGCG exhibited an additive antiproliferative effect, while methylation of 3,4-DHPAA was significantly decreased. 3OMGA exhibited the strongest antiproliferative activity among the phenolic acids. Conclusions The consumption of both, GT and BT, was associated with a significant increase in urinary and serum phenolic acids. PMID:23319439

Gastroprotective activity of Zanthoxylum rhoifolium Lam. in animal models.

PubMed

Freitas, F F B P; Fernandes, H B; Piauilino, C A; Pereira, S S; Carvalho, K I M; Chaves, M H; Soares, P M G; Miura, L M C V; Leite, J R S A; Oliveira, R C M; Oliveira, F A

2011-09-01

The stem barks of Zanthoxylum rhoifolium Lam. (Rutaceae), locally known as "mamica de cadela", are popularly used in dyspepsies, stomachic, tonic, antitumoral, antipyretic and are used in treating flatulence and colic. The objective of this study was to evaluate the gastroprotective effect of the ethanolic extract of Zanthoxylum rhoifolium (EEZR) stem barks in acute gastric lesion models, investigating their possible mechanisms. Mice were used for the evaluation of the acute toxicity, and mice and rats to study the gastroprotective activity. The gastroprotective action of EEZR was analyzed in the absolute ethanol, HCl/ethanol and indomethacin-induced gastric lesion models in mice, hypothermic-restraint stress, and ischemia/reperfusion in rats. In the investigation of the gastroprotective mechanisms of EEZR, the participation of the NO-synthase pathway, ATP-sensitive potassium channels (K(ATP)), the levels of the non-protein sulfhydril groups (NP-SH) and the catalase activity using the ethanol-induced gastric mucosa lesion model and the quantification of the gastric mucus and the antisecretory activity through pylorus ligature model in rats were analyzed. The animals did not present any signs of acute toxicity for the EEZR (up to the 4 g/kg dose, po), and it was not possible to calculate the DL(50). EEZR (125-500 mg/kg) exhibited a significant gastroprotective effect in absolute ethanol, HCl/ethanol, hypothermic-restraint stress, and ischemia/reperfusion-induced gastric lesion models. EEZR (250 and 500 mg/kg) exhibited still a gastroprotective activity in the indomethacin-induced ulcer model. Gastroprotection of EEZR was significantly decreased in pre-treated mice with l-NAME or glibenclamide, the respective nitric oxide synthase and K(ATP) channels inhibitors. Our studies revealed that EEZR (500 mg/kg) prevented the decrease of the non-protein sulfhydril groups (NP-SH) and increased the catalase levels in ethanol-treated animals. Furthermore, the extract (500 mg/kg) significantly increased the mucus production, however, the gastric secretion parameters (volume, [H(+)], pH) did not show any alteration. Our results indicate that the ethanolic extract of Zanthoxylum rhoifolium exhibits a significant gastroprotection, because it inhibits the formation of gastric lesions using different models. The release of the nitric oxide, the opening of the K(ATP) channels, the participation of the non-protein sulfhydril groups (NP-SH), catalase and the increase of mucous secretion seem to be involved in the gastroprotection activity of the EEZR. Nevertheless, this activity does not seem to be related to antisecretory mechanisms. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Strong climate and tectonic control on plagioclase weathering in granitic terrain

USGS Publications Warehouse

Rasmussen, C.; Brantley, S.; Richter, D.D.B.; Blum, A.; Dixon, J.; White, A.F.

2011-01-01

Investigations to understand linkages among climate, erosion and weathering are central to quantifying landscape evolution. We approach these linkages through synthesis of regolith data for granitic terrain compiled with respect to climate, geochemistry, and denudation rates for low sloping upland profiles. Focusing on Na as a proxy for plagioclase weathering, we quantified regolith Na depletion, Na mass loss, and the relative partitioning of denudation to physical and chemical contributions. The depth and magnitude of regolith Na depletion increased continuously with increasing water availability, except for locations with mean annual temperature <5??C that exhibited little Na depletion, and locations with physical erosion rates <20gm-2yr-1 that exhibited deep and complete regolith Na depletion. Surface Na depletion also tended to decrease with increasing physical erosion. Depth-integrated Na mass loss and regolith depth were both three orders of magnitude greater in the fully depleted, low erosion rate sites relative to other locations. These locations exhibited strong erosion-limitation of Na chemical weathering rates based on correlation of Na chemical weathering rate to total Na denudation. Sodium weathering rates in cool locations with positive annual water balance were strongly correlated to total Na denudation and precipitation, and exhibited an average apparent activation energy (Ea) of 69kJmol-1 Na. The remaining water-limited locations exhibited kinetic limitation of Na weathering rates with an Ea of 136kJmol-1 Na, roughly equivalent to the sum of laboratory measures of Ea and dissolution reaction enthalpy for albite. Water availability is suggested as the dominant factor limiting rate kinetics in the water-limited systems. Together, these data demonstrate marked transitions and nonlinearity in how climate and tectonics correlate to plagioclase chemical weathering and Na mass loss. ?? 2010 Elsevier B.V.

A new human mast cell line expressing a functional IgE receptor converts to tumorigenic growth by KIT D816V transfection.

PubMed

Saleh, Rosine; Wedeh, Ghaith; Herrmann, Harald; Bibi, Siham; Cerny-Reiterer, Sabine; Sadovnik, Irina; Blatt, Katharina; Hadzijusufovic, Emir; Jeanningros, Sylvie; Blanc, Catherine; Legarff-Tavernier, Magali; Chapiro, Elise; Nguyen-Khac, Florence; Subra, Frédéric; Bonnemye, Patrick; Dubreuil, Patrice; Desplat, Vanessa; Merle-Béral, Hélène; Willmann, Michael; Rülicke, Thomas; Valent, Peter; Arock, Michel

2014-07-03

In systemic mastocytosis (SM), clinical problems arise from factor-independent proliferation of mast cells (MCs) and the increased release of mediators by MCs, but no human cell line model for studying MC activation in the context of SM is available. We have created a stable stem cell factor (SCF) -dependent human MC line, ROSA(KIT WT), expressing a fully functional immunoglobulin E (IgE) receptor. Transfection with KIT D816V converted ROSA(KIT WT) cells into an SCF-independent clone, ROSA(KIT D816V), which produced a mastocytosis-like disease in NSG mice. Although several signaling pathways were activated, ROSA(KIT D816V) did not exhibit an increased, but did exhibit a decreased responsiveness to IgE-dependent stimuli. Moreover, NSG mice bearing ROSA(KIT D816V)-derived tumors did not show mediator-related symptoms, and KIT D816V-positive MCs obtained from patients with SM did not show increased IgE-dependent histamine release or CD63 upregulation. Our data show that KIT D816V is a disease-propagating oncoprotein, but it does not activate MCs to release proinflammatory mediators, which may explain why mediator-related symptoms in SM occur preferentially in the context of a coexisting allergy. ROSA(KIT D816V) may provide a valuable tool for studying the pathogenesis of mastocytosis and should facilitate the development of novel drugs for treating SM patients. © 2014 by The American Society of Hematology.

Activity of components of the antioxidant system in the roots of potato plants at short-term temperature drop and invasion with parasitic nematodes.

PubMed

Lavrova, V V; Matveeva, E M; Zinovieva, S V

2017-09-01

The activity of catalase and superoxide dismutase in the roots of susceptible plants and plants exposed to alternating temperatures, which were infected with the phytoparasitic nematode G. rostochiensis, was studied. It was found that, throughout the invasion period, the plants susceptible to invasion exhibited a high activity of these enzymes, which allowed them to maintain an active defense against the oxidative stress caused by the invasion and subsequent life activity of larvae. For the plants exposed to alternating temperatures, a decrease in the activity of catalase and superoxide dismutase at the early stages of invasion and an increase in the activity of these enzymes at the later stages was detected.

Structure and activity of Bombyx PBAN.

PubMed

Nagasawa, H; Kuniyoshi, H; Arima, R; Kawano, T; Ando, T; Suzuki, A

1994-01-01

Two structurally related molecular species of pheromone biosynthesis activating neuropeptides (PBANs), PBAN-I and -II, were isolated from adult heads of the silkworm, Bombyx mori, and characterized. PBAN-I is a carboxyl-terminally amidated 33-residue peptide. Structure-activity relationship studies revealed that 1) its carboxyl-terminal pentapeptide is the smallest size showing activity, 2) the carboxyl-terminal amide is indispensable for activity, and 3) oxidation of three Met residues in PBAN-I to Met(O) (methionine sulfoxide) caused marked enhancement of activity, and the three Met(O) residues contribute equally to the enhancement of activity. Molecular design of PBAN analogs using a carboxyl-terminal hexapeptide showed that modification of the amino-terminal amino group brought about a dramatic increase in activity. This increase was presumed to be mainly due to the increased stability in hemolymph. PBANs share the common carboxyl-terminal sequence, -Phe-Xaa-Pro-Arg-Leu-NH2, with myotropic peptides isolated from locust and cockroach. Examination of cross-activity of these two groups of peptides revealed that PBAN and its analogs exhibited myotropic activity comparable to myotropic peptides, while myotropic peptides showed extremely high pheromonotropic activity. In B. mori, PBAN activates sex pheromone (bombykol) production presumably by promoting the reduction reaction from acyl to alcohol, which is the last step in the biosynthesis of bombykol.

The human Cx26-D50A and Cx26-A88V mutations causing keratitis-ichthyosis-deafness syndrome display increased hemichannel activity

PubMed Central

Mhaske, Pallavi V.; Levit, Noah A.; Li, Leping; Wang, Hong-Zhan; Lee, Jack R.; Shuja, Zunaira; Brink, Peter R.

2013-01-01

Mutations in the human gene encoding connexin 26 (Cx26 or GJB2) cause either nonsyndromic deafness or syndromic deafness associated with skin diseases. That distinct clinical disorders can be caused by different mutations within the same gene suggests that different channel activities influence the ear and skin. Here we use three different expression systems to examine the functional characteristics of two Cx26 mutations causing either mild (Cx26-D50A) or lethal (Cx26-A88V) keratitis-ichthyosis-deafness (KID) syndrome. In either cRNA-injected Xenopus oocytes, transfected HeLa cells, or transfected primary human keratinocytes, we show that both Cx26-D50A and Cx26-A88V form active hemichannels that significantly increase membrane current flow compared with wild-type Cx26. This increased membrane current accelerated cell death in low extracellular calcium solutions and was not due to increased mutant protein expression. Elevated mutant hemichannel currents could be blocked by increased extracellular calcium concentration. These results show that these two mutations exhibit a shared gain of functional activity and support the hypothesis that increased hemichannel activity is a common feature of human Cx26 mutations responsible for KID syndrome. PMID:23447037

KOH catalysed preparation of activated carbon aerogels for dye adsorption.

PubMed

Ling, Sie King; Tian, H Y; Wang, Shaobin; Rufford, Thomas; Zhu, Z H; Buckley, C E

2011-05-01

Organic carbon aerogels (CAs) were prepared by a sol-gel method from polymerisation of resorcinol, furfural, and hexamethylenetetramine catalysed by KOH at around pH 9 using ambient pressure drying. The effect of KOH in the sol-gel on CA synthesis was studied. It was found that addition of KOH prior to the sol-gel polymerisation process improved thermal stability of the gel, prevented the crystallinity of the gel to graphite, increased the microporosity of CA and promoted activation of CA. The CAs prepared using the KOH catalyst exhibited higher porosity than uncatalysed prepared samples. Activation in CO(2) at higher temperature also enhanced the porosity of CAs. Adsorption tests indicated that the CAs were effective for both basic and acid dye adsorption and the adsorption increased with increasing surface area and pore volume. The kinetic adsorption of dyes was diffusion control and could be described by the second-order kinetic model. The equilibrium adsorption of dyes was higher than activated carbon. Copyright © 2011 Elsevier Inc. All rights reserved.

Effects of different cellulases on the release of phenolic acids from rice straw during saccharification.

PubMed

Xue, Yiyun; Wang, Xiahui; Chen, Xingxuan; Hu, Jiajun; Gao, Min-Tian; Li, Jixiang

2017-06-01

Effects of different cellulases on the release of phenolic acids from rice straw during saccharification were investigated in this study. All cellulases tested increased the contents of phenolic acids during saccharification. However, few free phenolic acids were detected, as they were present in conjugated form after saccharification when the cellulases from Trichoderma reesei, Trichoderma viride and Aspergillus niger were used. On the other hand, phenolic acids were present in free form when the Acremonium cellulolyticus cellulase was used. Assays of enzyme activity showed that, besides high cellulase activity, the A. cellulolyticus cellulase exhibited high feruloyl esterase (FAE) activity. A synergistic interaction between FAE and cellulase led to the increase in free phenolic acids, and thus an increase in antioxidative and antiradical activities of the phenolic acids. Moreover, a cost estimation demonstrated the feasibility of phenolic acids as value-added products to reduce the total production cost of ethanol. Copyright © 2017 Elsevier Ltd. All rights reserved.

Predator-induced defenses in tadpoles confound body stoichiometry predictions of the general stress paradigm.

PubMed

Costello, David M; Michel, Matt J

2013-10-01

Predation is known to have both direct and indirect effects on nutrient cycling in terrestrial and aquatic ecosystems, and the general stress paradigm (GSP) has been promoted as a theory for describing predator-mediated indirect effects on nutrient cycling. The GSP predicts that prey exposed to predators will produce glucocorticosteroids, which have a host of physiological effects including gluconeogenesis, increased respiration, excretion of N and P, and increases in body C:N. We tested the nutrient predictions of the GSP using anuran larvae, which exhibit morphological defenses in addition to behavioral defenses for which the GSP was conceived. Genetically similar Hyla versicolor tadpoles were placed in mesocosms either in the presence or absence of a fed predator (Dytiscus verticalis), and after two weeks, tadpoles exposed to predators exhibited strong induced defenses with large, tubular bodies, larger tails, and reduced activity. Tadpole body %C and N:P increased with no change in C:N, which is contrary to expectations from the GSP. Statistical models suggested that changes in body morphology (e.g., tail muscle width) rather than behavioral defenses (i.e., reduced activity) were most likely responsible for predator-mediated differences in body stoichiometry. This study suggests that strong morphological defenses may overwhelm or counteract the nutrient predictions of the GSP.

Do cancer cells in human and meristematic cells in plant exhibit similar responses toward plant extracts with cytotoxic activities?

PubMed

Khalifa, Noha S; Barakat, Hoda S; Elhallouty, Salwa; Salem, Dina

2015-01-01

We examined the effect of water extracts of Persea americana fruit, and of the leaves of Tabernamontana divericata, Nerium oleander and Annona cherimolia (positive control) on Vicia faba root cells. We had confirmed in our previously published data the cytotoxicity of these plant extracts on four human cancer cell lines: liver (HepG-2), lung (A549), colon (HT-29) and breast (MCF-7). Vicia faba roots were soaked in plant extracts at dilutions of 100, 1,250, 2,500, 5,000, 10,000, 20,000 ppm for 4 and 24 h. All treatments resulted in a significant reduction in the mitotic index in a dose dependant manner. Root cells treated with T. divericata, N. oleander and A. cherimolia exhibited a decrease in prophase cell percentage, increase in micronuclei and chromosomal abnormalities as concentration increased. The P. americana treatment showed the highest cytotoxic effect on cancer cells, prophase cell percentage increased linearly with the applied concentration and no micronuclei were detected. This study shows that root tip assay of beans can be used in initial screening for new plant extracts to validate their use as candidates for containing active cytotoxic agents against malignant cells. This will greatly help in exploring new plant extracts as drugs for cancer treatment.

Antibacterial activity of selected medicinal plants against multiple antibiotic resistant uropathogens: a study from Kolli Hills, Tamil Nadu, India.

PubMed

Narayanan, A S; Raja, S S S; Ponmurugan, K; Kandekar, S C; Natarajaseenivasan, K; Maripandi, A; Mandeel, Q A

2011-09-01

The increasing incidence of antibiotic resistance among bacterial pathogens necessitates medicinal plants as an alternate therapy in restricting the resistant infectious organisms. In this primitive study, the antibiotic resistance of organisms isolated from urinary tract infected patients was evaluated using the National Committee for Clinical Laboratory Standards (NCCLS) method and Multiple Antibiotic Resistance (MAR) index values, and the MAR values was also calculated for plant extracts. The 10 common medicinal plants collected from Kolli hills, Namakkal, south India were extracted using the chloroform, methanol, acetone, ethanol and saponification procedure. The efficacy of the extracts on the uropathogens was tested by agar disc diffusion method in order to analyse the inhibitory activity of plant extract on the organisms. Azadiracta indica A. Juss., Tinospora cordifolia (Wild.) and Euphorbia hirta Linn. exhibited high inhibitory activity against most of the 11 tested organisms followed by Cassia javanica Linn. and Phyllanthus niruri Linn. The maximum zone size of 46.3 mm was exhibited by methanol extract of P. niruri Linn. against Pseudomonas aeruginosa. Asparagus racemosus Willd. and Eupatorium triplinerve Vahl had the least activity against resistant pathogens. Saponified lipids of most of the plants exhibited maximum antibacterial activity. Among the tested organisms, P. aeruginosa and Staphylococcus epidermidis were the most susceptible and Serratia marcescens, Enterobacter cloaceae, Citrobacter koseri, and Citrobacter freundii were the least inhibited by most of the extracts of medicinal plants. It is concluded that revised antibiotic policies and more importantly the development of herbal medicine as an alternative may be incorporated in urological practice.

Prenatal and Postnatal Expression of Glutathione Transferase ζ 1 in Human Liver and the Roles of Haplotype and Subject Age in Determining Activity with Dichloroacetate

PubMed Central

Li, Wenjun; Gu, Yuan; Hines, Ronald N.; Simpson, Pippa; Langaee, Taimour; Stacpoole, Peter W.

2012-01-01

Glutathione transferase ζ 1 (GSTZ1), also known as maleylacetoacetate isomerase, catalyzes the penultimate step of tyrosine catabolism and metabolizes several α-halocarboxylic acids, including dichloroacetic acid (DCA), an investigational drug used for lactic acidosis and, recently, solid tumors. Age-related differences have been suggested in DCA pharmacotoxicology, but no information is available on GSTZ1 ontogeny in humans. Here, we investigated the cytosolic GSTZ1 developmental expression pattern and the influence of haplotype on GSTZ1 activity with DCA by using human livers from donors between 10 weeks gestation and 74 years. GSTZ1 expression was very low in fetal livers (<2 pmol of GSTZ1/mg cytosol). The expression began to increase after birth in an age-dependent manner until age 7 years. GSTZ1 was then sustained at stable, yet variable, levels (median, 20.0 pmol/mg cytosol; range, 4.8–47.3 pmol/mg cytosol) until age 74 years. GSTZ1 activity with DCA was strongly associated with haplotype and expression level. Samples homozygous or heterozygous for GSTZ1A exhibited ∼3-fold higher DCA dechlorinating activity than samples carrying other alleles at a given level of expression. The correlations (r2) between activity and expression were 0.90 and 0.68, respectively, for GSTZ1A carriers (n = 11) and noncarriers (n = 61). GSTZ1 is expressed in mitochondria in addition to cytosol. The GSTZ1A allele exhibited similar effects in the mitochondrial fraction by conferring a higher activity with DCA. In summary, we report a neonatal onset and an age-related increase in GSTZ1 protein expression during human liver development. Haplotype influenced GSTZ1 activity with DCA but not protein expression. PMID:22028318

Hepatitis C virus NS3 helicase forms oligomeric structures that exhibit optimal DNA unwinding activity in vitro.

PubMed

Sikora, Bartek; Chen, Yingfeng; Lichti, Cheryl F; Harrison, Melody K; Jennings, Thomas A; Tang, Yong; Tackett, Alan J; Jordan, John B; Sakon, Joshua; Cameron, Craig E; Raney, Kevin D

2008-04-25

HCV NS3 helicase exhibits activity toward DNA and RNA substrates. The DNA helicase activity of NS3 has been proposed to be optimal when multiple NS3 molecules are bound to the same substrate molecule. NS3 catalyzes little or no measurable DNA unwinding under single cycle conditions in which the concentration of substrate exceeds the concentration of enzyme by 5-fold. However, when NS3 (100 nm) is equimolar with the substrate, a small burst amplitude of approximately 8 nm is observed. The burst amplitude increases as the enzyme concentration increases, consistent with the idea that multiple molecules are needed for optimal unwinding. Protein-protein interactions may facilitate optimal activity, so the oligomeric properties of the enzyme were investigated. Chemical cross-linking indicates that full-length NS3 forms higher order oligomers much more readily than the NS3 helicase domain. Dynamic light scattering indicates that full-length NS3 exists as an oligomer, whereas NS3 helicase domain exists in a monomeric form in solution. Size exclusion chromatography also indicates that full-length NS3 behaves as an oligomer in solution, whereas the NS3 helicase domain behaves as a monomer. When NS3 was passed through a small pore filter capable of removing protein aggregates, greater than 95% of the protein and the DNA unwinding activity was removed from solution. In contrast, only approximately 10% of NS3 helicase domain and approximately 20% of the associated DNA unwinding activity was removed from solution after passage through the small pore filter. The results indicate that the optimally active form of full-length NS3 is part of an oligomeric species in vitro.

Transition in Survival From Low-Dose Hyper-Radiosensitivity to Increased Radioresistance Is Independent of Activation of ATM SER1981 Activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krueger, Sarah A.; Collis, Spencer J.; Joiner, Michael C.

2007-11-15

Purpose: The molecular basis of low-dose hyper-radiosensitivity (HRS) is only partially understood. The aim of this study was to define the roles of ataxia telangiectasia mutated (ATM) activity and the downstream ATM-dependent G{sub 2}-phase cell cycle checkpoint in overcoming HRS and triggering radiation resistance. Methods and Materials: Survival was measured using a high-resolution clonogenic assay. ATM Ser1981 activation was measured by Western blotting. The role of ATM was determined in survival experiments after molecular (siRNA) and chemical (0.4 mM caffeine) inhibition and chemical (20 {mu}g/mL chloroquine, 15 {mu}M genistein) activation 4-6 h before irradiation. Checkpoint responsiveness was assessed in eightmore » cell lines of differing HRS status using flow cytometry to quantify the progression of irradiated (0-2 Gy) G{sub 2}-phase cells entering mitosis, using histone H3 phosphorylation analysis. Results: The dose-response pattern of ATM activation was concordant with the transition from HRS to radioresistance. However, ATM activation did not play a primary role in initiating increased radioresistance. Rather, a relationship was discovered between the function of the downstream ATM-dependent early G{sub 2}-phase checkpoint and the prevalence and overcoming of HRS. Four cell lines that exhibited HRS failed to show low-dose (<0.3-Gy) checkpoint function. In contrast, four HRS-negative cell lines exhibited immediate cell cycle arrest for the entire 0-2-Gy dose range. Conclusion: Overcoming HRS is reliant on the function of the early G{sub 2}-phase checkpoint. These data suggest that clinical exploitation of HRS could be achieved by combining radiotherapy with chemotherapeutic agents that modulate this cell cycle checkpoint.« less

7 CFR Exhibit A to Subpart B of... - Grant Agreement-Growth Management and Housing Planning for Approved Designated Energy Impacted Areas

Code of Federal Regulations, 2011 CFR

2011-01-01

... met; (iii) Problems, delays, or adverse conditions which will materially affect attainment of planned... process which will improve local conditions and alleviate problems associated with increased coal or... Grantee programs, projects, related activities, and problems. (b) The Grantee shall inform the Grantor as...

Physical Activity into Socialization: A Movement-Based Social Skills Program for Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Lee, Jihyun; Vargo, Kristina K.

2017-01-01

Children with autism spectrum disorder (ASD) often exhibit deficits in social-communicative behaviors. Given the increased prevalence of children with ASD, programs designed to teach social-communicative behaviors are necessary. This article introduces a movement-based program that embeds social-skill components to improve the motor skills and…

Extracting Intrinsic Functional Networks with Feature-Based Group Independent Component Analysis

ERIC Educational Resources Information Center

Calhoun, Vince D.; Allen, Elena

2013-01-01

There is increasing use of functional imaging data to understand the macro-connectome of the human brain. Of particular interest is the structure and function of intrinsic networks (regions exhibiting temporally coherent activity both at rest and while a task is being performed), which account for a significant portion of the variance in…

The regulation of rat activity following exposure to hyperdynamic fields

NASA Technical Reports Server (NTRS)

Fuller, Charles A.; Ishihama, Linda M.; Murakami, Dean M.

1993-01-01

The microgravity of space flight and the hyperdynamic fields produced via centrifugation have allowed researchers to examine the effect of altered gravitational environments on the regulation of physiological systems. In this study, a high frequency light/dark cycle was provided for 24 hours as an environmental challenge to assess the recovery of homeostatic and circadian components of physiological regulation in rats. For example, the nocturnal rat exhibited a homeostatic increase in body temperature during the dark periods and a decrease during the light periods. In addition, the magnitude of the body temperature response exhibits a time of day variation demonstrating the effect on circadian regulation.

Localization and Characterization of α-Glucosidase Activity in Brettanomyces lambicus

PubMed Central

Kumara, H. M. C. Shantha; De Cort, S.; Verachtert, H.

1993-01-01

Brettanomyces lambicus was isolated and identified from a typical overattenuating Belgian lambic beer and exhibited extracellular and intracellular α-glucosidase activities. Production of the intracellular enzyme was higher than production of the extracellular enzyme, and localization studies showed that the intracellular α-glucosidase is mostly soluble and partially cell wall bound. Both intracellular and extracellular enzymes were purified by ammonium sulfate precipitation, gel filtration (Sephadex G-150, Sephadex G-200, Ultrogel AcA-44), and ion-exchange chromatography (sulfopropyl-Sephadex C-50, (carboxymethyl-Sephadex C-50). The intracellular α-glucosidase exhibited optimum activity at 39°C and pH 6.2. The extracellular enzyme exhibited optimum catalytic activity at 40°C and pH 6.0. The molecular masses of purified intracellular and extracellular α-glucosidases, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were 72,500 and 77,250, respectively. For both enzymes there was a decrease in the rate of hydrolysis with an increase in the degree of polymerization, and both enzymes hydrolyzed dextrins isolated from lambic wort (degrees of polymerization, 3 to 9 and more than 9). The Km values for p-nitrophenyl-α-d-glucopyranoside, maltose, and maltotriose for the intracellular enzyme were 0.9, 3.4, and 3.7 mM, respectively. The Ki values for both enzymes were between 28.5 and 57 μM for acarbose and between 7.45 and 15.7 mM for Tris. These enzymes are probably involved in the overattenuation of spontaneously fermented lambic beer. Images PMID:16349005

Localization and Characterization of alpha-Glucosidase Activity in Brettanomyces lambicus.

PubMed

Kumara, H M; De Cort, S; Verachtert, H

1993-08-01

Brettanomyces lambicus was isolated and identified from a typical overattenuating Belgian lambic beer and exhibited extracellular and intracellular alpha-glucosidase activities. Production of the intracellular enzyme was higher than production of the extracellular enzyme, and localization studies showed that the intracellular alpha-glucosidase is mostly soluble and partially cell wall bound. Both intracellular and extracellular enzymes were purified by ammonium sulfate precipitation, gel filtration (Sephadex G-150, Sephadex G-200, Ultrogel AcA-44), and ion-exchange chromatography (sulfopropyl-Sephadex C-50, (carboxymethyl-Sephadex C-50). The intracellular alpha-glucosidase exhibited optimum activity at 39 degrees C and pH 6.2. The extracellular enzyme exhibited optimum catalytic activity at 40 degrees C and pH 6.0. The molecular masses of purified intracellular and extracellular alpha-glucosidases, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, were 72,500 and 77,250, respectively. For both enzymes there was a decrease in the rate of hydrolysis with an increase in the degree of polymerization, and both enzymes hydrolyzed dextrins isolated from lambic wort (degrees of polymerization, 3 to 9 and more than 9). The K(m) values for p-nitrophenyl-alpha-d-glucopyranoside, maltose, and maltotriose for the intracellular enzyme were 0.9, 3.4, and 3.7 mM, respectively. The K(i) values for both enzymes were between 28.5 and 57 muM for acarbose and between 7.45 and 15.7 mM for Tris. These enzymes are probably involved in the overattenuation of spontaneously fermented lambic beer.

Convergent properties of vestibular-related brain stem neurons in the gerbil

NASA Technical Reports Server (NTRS)

Kaufman, G. D.; Shinder, M. E.; Perachio, A. A.

2000-01-01

Three classes of vestibular-related neurons were found in and near the prepositus and medial vestibular nuclei of alert or decerebrate gerbils, those responding to: horizontal translational motion, horizontal head rotation, or both. Their distribution ratios were 1:2:2, respectively. Many cells responsive to translational motion exhibited spatiotemporal characteristics with both response gain and phase varying as a function of the stimulus vector angle. Rotationally sensitive neurons were distributed as Type I, II, or III responses (sensitive to ipsilateral, contralateral, or both directions, respectively) in the ratios of 4:6:1. Four tested factors shaped the response dynamics of the sampled neurons: canal-otolith convergence, oculomotor-related activity, rotational Type (I or II), and the phase of the maximum response. Type I nonconvergent cells displayed increasing gains with increasing rotational stimulus frequency (0.1-2.0 Hz, 60 degrees /s), whereas Type II neurons with convergent inputs had response gains that markedly decreased with increasing translational stimulus frequency (0.25-2.0 Hz, +/-0.1 g). Type I convergent and Type II nonconvergent neurons exhibited essentially flat gains across the stimulus frequency range. Oculomotor-related activity was noted in 30% of the cells across all functional types, appearing as burst/pause discharge patterns related to the fast phase of nystagmus during head rotation. Oculomotor-related activity was correlated with enhanced dynamic range compared with the same category that had no oculomotor-related response. Finally, responses that were in-phase with head velocity during rotation exhibited greater gains with stimulus frequency increments than neurons with out-of-phase responses. In contrast, for translational motion, neurons out of phase with head acceleration exhibited low-pass characteristics, whereas in-phase neurons did not. Data from decerebrate preparations revealed that although similar response types could be detected, the sampled cells generally had lower background discharge rates, on average one-third lower response gains, and convergent properties that differed from those found in the alert animals. On the basis of the dynamic response of identified cell types, we propose a pair of models in which inhibitory input from vestibular-related neurons converges on oculomotor neurons with excitatory inputs from the vestibular nuclei. Simple signal convergence and combinations of different types of vestibular labyrinth information can enrich the dynamic characteristics of the rotational and translational vestibuloocular responses.

Influence of spray time on the optical and electrical properties of CoNi2S4 thin films

NASA Astrophysics Data System (ADS)

El Radaf, I. M.; Fouad, S. S.; Ismail, A. M.; Sakr, G. B.

2018-04-01

In this paper, a facile spray pyrolysis technique was utilized to synthesize CoNi2S4 thin films. The influence of spray time on the structural, optical and electrical properties of the CoNi2S4 thin films was studied. The x-ray diffraction studies of the CoNi2S4 thin films illustrate that the films exhibit a polycrystalline nature with cubic structure. The values of the lattice strain ε, and the dislocation density δ, were decreased as the spray time increase while the grain size has reverse manner to lattice strain ε, and the dislocation density δ. The transmittance and reflectance spectra of the CoNi2S4 thin films were recorded in the wavelength range of (400–2500) nm to evaluate the optical parameters of the CoNi2S4 thin films. Optical absorption coefficient of CoNi2S4 thin films revealed a presence of a direct energy gap and the values of energy gap were decreased from 1.68 to 1.53 eV as the spray time increases from 15 min to 45 min. The nonlinear refractive index of the CoNi2S4 thin films was increased with increasing of the spray time. The CoNi2S4 thin films exhibit single activation energy and the activation energy was decreased as the spray time increased.

Reestablishment of Energy Balance in a Male Mouse Model With POMC Neuron Deletion of BMPR1A.

PubMed

Townsend, Kristy L; Madden, Christopher J; Blaszkiewicz, Magdalena; McDougall, Lindsay; Tupone, Domenico; Lynes, Matthew D; Mishina, Yuji; Yu, Paul; Morrison, Shaun F; Tseng, Yu-Hua

2017-12-01

The regulation of energy balance involves complex processes in the brain, including coordination by hypothalamic neurons that contain pro-opiomelanocortin (POMC). We previously demonstrated that central bone morphogenetic protein (BMP) 7 reduced appetite. Now we show that a type 1 BMP receptor, BMPR1A, is colocalized with POMC neurons and that POMC-BMPR1A-knockout (KO) mice are hyperphagic, revealing physiological involvement of BMP signaling in anorectic POMC neurons in the regulation of appetite. Surprisingly, the hyperphagic POMC-BMPR1A-KO mice exhibited a lack of obesity, even on a 45% high-fat diet. This is because the brown adipose tissue (BAT) of KO animals exhibited increased sympathetic activation and greater thermogenic capacity owing to a reestablishment of energy balance, most likely stemming from a compensatory increase of BMPR1A in the whole hypothalamus of KO mice. Indeed, control animals given central BMP7 displayed increased energy expenditure and a specific increase in sympathetic nerve activity (SNA) in BAT. In these animals, pharmacological blockade of BMPR1A-SMAD signaling blunted the ability of BMP7 to increase energy expenditure or BAT SNA. Together, we demonstrated an important role for hypothalamic BMP signaling in the regulation of energy balance, including BMPR1A-mediated appetite regulation in POMC neurons as well as hypothalamic BMP-SMAD regulation of the sympathetic drive to BAT for thermogenesis. Copyright © 2017 Endocrine Society.

Rice Seed Germination Underwater: Morpho-Physiological Responses and the Bases of Differential Expression of Alcoholic Fermentation Enzymes

PubMed Central

Miro, Berta; Longkumer, Toshisangba; Entila, Frederickson D.; Kohli, Ajay; Ismail, Abdelbagi M.

2017-01-01

The water-, energy-, and labor-intensive system of transplanted puddled rice (Oryza sativa) is steadily being replaced by direct seeding due to the progressive scarcity of these resources. However, the alternate dry direct seeding leads to competition with weeds and poor establishment when soils are flooded. Direct seeded rice capable of anaerobic germination (germination in flooded soil, AG) is ideal, which under rainfed ecosystems would also overcome waterlogging during germination. AG tolerance is associated with faster germination and faster elongation of coleoptiles, with the activities of alcoholic fermentation enzymes replacing aerobic respiration as a source of energy. To better understand the variability in the morpho-physiological responses and in the nature of the alcoholic fermentation enzymes during AG, 21 rice genotypes were studied. The genotypes Khao Hlan On (KHO) and IR42 were used as the tolerant and susceptible checks, respectively. KHO exhibited faster germination, with 82.5% of the coleoptiles emerging out of 10 cm of water within 8 days, whereas IR42 exhibited 20% germination and limited coleoptile growth. Among the test genotypes, four performed well, including two that are drought tolerant. Increased content and activity of the alcoholic fermentation enzymes, alcohol dehydrogenase (ADH1) and acetaldehyde dehydrogenase (ALDH2a and ALDH2b), was noted in KHO under anaerobic than under aerobic conditions and also in comparison with IR42 under AG. Gene transcripts for these enzymes were also more in KHO undergoing AG. However, no major differences were observed between KHO and IR42 in the critical cis-acting regulatory elements, such as the auxin, light, and sugar response elements, in the promoters of ADH1, ALDH2a, and ALDH2b genes. Post-transcriptional and post-translational regulatory mechanisms were implicated for the increased transcript and protein content/activity of the enzymes in KHO by observing four different transcripts of ALDH2a and a unique non-glycosylated form of ADH1 under AG. IR42 lacked the non-glycosylated ADH1 and contained only a truncated form of ALDH2a, which lacked the active site. Additionally, KHO exhibited increased activity and more isoforms for reactive oxygen species detoxifying enzymes under AG compared to IR42. These results highlight the need for a deeper functional understanding of the critical enzymes involved in AG. PMID:29123541

Amphetamine increases activity but not exploration in humans and mice

PubMed Central

Minassian, Arpi; Young, Jared W.; Cope, Zackary A.; Henry, Brook L.; Geyer, Mark A.; Perry, William

2015-01-01

Rationale Cross-species quantification of physiological behavior enables a better understanding of the biological systems underlying neuropsychiatric diseases such as Bipolar Disorder (BD). Cardinal symptoms of manic BD include increased motor activity and goal-directed behavior, thought to be related to increased catecholamine activity, potentially selective to dopamine homeostatic dysregulation. Objectives The objective of this study was to test whether acute administration of amphetamine, a norepinephrine/dopamine transporter inhibitor and dopamine releaser, would replicate the profile of activity and exploration observed in both humans with manic BD and mouse models of mania. Methods Healthy volunteers with no psychiatric history were randomized to a one-time dose of placebo (n=25), 10 mg d-amphetamine (n=18), or 20 mg amphetamine (n=23). 80 mice were administered one of 4 doses of d-amphetamine or vehicle. Humans and mice were tested in the Behavioral Pattern Monitor (BPM), which quantifies motor activity, exploratory behavior, and spatial patterns of behavior. Results In humans, the 20-mg dose of amphetamine increased motor activity as measured by acceleration without marked effects on exploration or spatial patterns of activity. In mice, amphetamine increased activity, decreased specific exploration, and caused straighter, one-dimensional movements in a dose-dependent manner. Conclusions Consistent with mice, amphetamine increased motoric activity in humans without increasing exploration. Given that BD patients exhibit heightened exploration, these data further emphasize the limitation of amphetamine-induced hyperactivity as a suitable model for BD. Further, these studies highlight the utility of cross-species physiological paradigms in validating biological mechanisms of psychiatric diseases. PMID:26449721

Increased Amino Acid Uptake Supports Autophagy-Deficient Cell Survival upon Glutamine Deprivation.

PubMed

Zhang, Nan; Yang, Xin; Yuan, Fengjie; Zhang, Luyao; Wang, Yanan; Wang, Lina; Mao, Zebin; Luo, Jianyuan; Zhang, Hongquan; Zhu, Wei-Guo; Zhao, Ying

2018-06-05

Autophagy is a protein degradation process by which intracellular materials are recycled for energy homeostasis. However, the metabolic status and energy source of autophagy-defective tumor cells are poorly understood. Here, our data show that amino acid uptake from the extracellular environment is increased in autophagy-deficient cells upon glutamine deprivation. This elevated amino acid uptake results from activating transcription factor 4 (ATF4)-dependent upregulation of AAT (amino acid transporter) gene expression. Furthermore, we identify SIRT6, a NAD + -dependent histone deacetylase, as a corepressor of ATF4 transcriptional activity. In autophagy-deficient cells, activated NRF2 enhances ATF4 transcriptional activity by disrupting the interaction between SIRT6 and ATF4. In this way, autophagy-deficient cells exhibit increased AAT expression and show increased amino acid uptake. Notably, inhibition of amino acid uptake reduces the viability of glutamine-deprived autophagy-deficient cells, but not significantly in wild-type cells, suggesting reliance of autophagy-deficient tumor cells on extracellular amino acid uptake. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Catalytic properties of thermophilic lactate dehydrogenase and halophilic malate dehydrogenase at high temperature and low water activity.

PubMed

Hecht, K; Wrba, A; Jaenicke, R

1989-07-15

Thermophilic lactate dehydrogenases from Thermotoga maritima and Bacillus stearothermophilus are stable up to temperature limits close to the optimum growth temperature of their parent organisms. Their catalytic properties are anomalous in that Km shows a drastic increase with increasing temperature. At low temperatures, the effect levels off. Extreme halophilic malate dehydrogenase from Halobacterium marismortui exhibits a similar anomaly. Increasing salt concentration (NaCl) leads to an optimum curve for Km, oxaloacctate while Km, NADH remains constant. Previous claims that the activity of halophilic malate dehydrogenase shows a maximum at 1.25 M NaCl are caused by limiting substrate concentration; at substrate saturation, specific activity of halophilic malate dehydrogenase reaches a constant value at ionic strengths I greater than or equal to 1 M. Non-halophilic (mitochondrial) malate dehydrogenase shows Km characteristics similar to those observed for the halophilic enzyme. The drastic decrease in specific activity of the mitochondrial enzyme at elevated salt concentrations is caused by the salt-induced increase in rigidity of the enzyme, rather than gross structural changes.

Substituted 2-benzothiazolamines as sodium flux inhibitors: quantitative structure-activity relationships and anticonvulsant activity.

PubMed

Hays, S J; Rice, M J; Ortwine, D F; Johnson, G; Schwarz, R D; Boyd, D K; Copeland, L F; Vartanian, M G; Boxer, P A

1994-10-01

Thirty-two aryl-substituted 2-benzothiazolamines have been tested for their ability to modulate sodium flux in rat cortical slices. A QSAR analysis, applied to these derivatives, showed a trend toward increasing potency as sodium flux inhibitors with increasing lipophilicity, decreasing size, and increasing electron withdrawal of the benzo ring substituents. Additionally, 4- or 5-substitution of the benzo ring was found to decrease potency. The combination of increased lipophilicity, small size, and electron withdrawal severely limited which groups were tolerated on the benzo ring, thus suggesting that the optimal substitution patterns have been prepared within this series. Nine of these compounds were potent inhibitors of veratridine-induced sodium flux (NaFl). These nine compounds also proved to be anticonvulsant in the maximal electroshock (MES) assay. Fourteen additional 2-benzothiazolamines demonstrated activity in the MES screen, yet exhibited no activity in the NaFl assay. These derivatives may be interacting at the sodium channel in a manner not discernible by the flux paradigm, or they may be acting by an alternative mechanism in vivo.

ZIF-67 incorporated with carbon derived from pomelo peels: A highly efficient bifunctional catalyst for oxygen reduction/evolution reactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hao; Yin, Feng-Xiang; Chen, Biao-Hua

Developing carbon catalyst materials using natural, abundant and renewable resources as precursors plays an increasingly important role in clean energy generation and environmental protection. In this work, N-doped pomelo-peel-derived carbon (NPC) materials were prepared using a widely available food waste-pomelo peels and melamine. The synthetic NPC exhibits well-defined porosities and a highly doped-N content (e.g. 6.38 at% for NPC-2), therefore affords excellent oxygen reduction reaction (ORR) catalytic activities in alkaline electrolytes. NPC was further integrated with ZIF-67 to form ZIF-67@NPC hybrids through solvothermal reactions. The hybrid catalysts show substantially enhanced ORR catalytic activities comparable to that of commercial 20 wamore » Pt/C. Furthermore, the catalysts also exhibit excellent oxygen evolution reaction (OER) catalytic activities. Among all prepared ZIF-67@NPC hybrids, the optimal composition with ZIF-67 to NPC ratio of 2:1 exhibits the best ORR and OER bifunctional catalytic performance and the smallest Delta E (E-OER@10 mA cm(-2)-E-ORR@-1 mA cm(-2)) value of 0.79 V. The catalyst also demonstrated desirable 4-electron transfer pathways and superior catalytic stabilities. The Co-N-4 in ZIF-67, electrochemical active surface area, and the strong interactions between ZIF-67 and NPC are attributed as the main contributors to the bifunctional catalytic activities. These factors act synergistically, resulting in substantially enhanced bifunctional catalytic activities and stabilities; consequently, this hybrid catalyst is among the best of the reported bifunctional electrocatalysts and is promising for use in metal-air batteries and fuel cells. (C) 2016 Elsevier B.V. All rights reserved.« less

Evaluation Physical Characteristics and Comparison Antimicrobial and Anti-Inflammation Potentials of Dental Root Canal Sealers Containing Hinokitiol In Vitro

PubMed Central

Shih, Yin-Hua; Lin, Dan-Jae; Chang, Kuo-Wei; Hsia, Shih-Min; Ko, Shun-Yao; Lee, Shyh-Yuan; Hsue, Shui-Sang; Wang, Tong-Hong; Chen, Yi-Ling; Shieh, Tzong-Ming

2014-01-01

Hinokitiol displays potent antimicrobial activity. It has been used in toothpaste and oral-care gel to improve the oral lichen planus and reduce halitosis. The aim of this study was to evaluate the antimicrobial activity of 3 different dental root canal sealers with hinokitiol (sealers+H) and their physical and biological effects. AH Plus (epoxy amine resin-based, AH), Apexit Plus (calcium-hydroxide-based, AP), and Canals (zinc-oxide-eugenol-based, CA), were used in this study. The original AH and CA exhibited strong anti-methicillin-resistant Staphylococcus aureus (anti-MRSA) activity, but AP did not. The setting time, working time, flowability, film thickness, and solubility of each sealer+0.2%H complied with ISO 6876:2001. CA+0.2%H exhibited high cytotoxicity, but the others sealers+0.2%H did not. Because hinokitiol combined with Zn2+ in CA creates a synergistic effect. The physical tests of AP+0.5%–1%H complied with ISO 6876:2001, improved antimicrobial activity, inhibited inflammation genes cyclooxygenase-2 (COX-2) and hypoxia-inducible factor-1α (HIF-1α) mRNA in MG-63 cells and human gingival fibroblasts (HGF), and down-regulated lysyl oxidase (LOX) mRNA of HGF. In summary, AH and CA demonstrated strong antimicrobial activity, but AP did not. Application of hinokitiol increases AH anti-MRSA activity should less than 0.2% for keep well flowability. AP+0.5%–1% hinokitiol exhibited strong physical, antibacterial, and anti-inflammation potentials, and inhibited S. aureus abscess formation. Applying an appreciable proportion of hinokitiol to epoxy-amine-resin-based and calcium-hydroxide-based root canal sealers is warranted, but the enhanced cytotoxicity and synergistic effect must be considered. PMID:24915566

Dose-dependent effects of β-phenylglutamic acid hydrochloride (RGPU-135, neuroglutam) on animal behavior.

PubMed

Tyurenkov, I N; Bagmetova, V V; Chernyshova, Yu V; Merkushenkova, O V

2014-12-01

β-Phenylglutamic acid hydrochloride (RGPU-135, neuroglutam) in doses of 13-650 mg/kg suppressed depressive behavior of animals in the Porsolt test (i.e. produced antidepressant properties), reduced anxiety in the open-field, elevated plus maze, and Vogel conflict tests (i.e. produced anxiolytic effects). RGPU-135 in doses of 26-130 mg/kg exhibited more pronounced antidepressant action and in doses of 26 and 52 mg/kg had more pronounced anxiolytic effects. RGPU-135 in doses of 13-78 mg/kg increased locomotor and exploratory activity of animals in the open-field test. Activating effects of this agent decreased with increasing the dose. RGPU-135 in the subtoxic dose (650 mg/kg) suppressed locomotor activity of animals (produced sedative effect).

Lithium-aluminum-iron electrode composition

DOEpatents

Kaun, Thomas D.

1979-01-01

A negative electrode composition is presented for use in a secondary electrochemical cell. The cell also includes an electrolyte with lithium ions such as a molten salt of alkali metal halides or alkaline earth metal halides that can be used in high-temperature cells. The cell's positive electrode contains a a chalcogen or a metal chalcogenide as the active electrode material. The negative electrode composition includes up to 50 atom percent lithium as the active electrode constituent in an alloy of aluminum-iron. Various binary and ternary intermetallic phases of lithium, aluminum and iron are formed. The lithium within the intermetallic phase of Al.sub.5 Fe.sub.2 exhibits increased activity over that of lithium within a lithium-aluminum alloy to provide an increased cell potential of up to about 0.25 volt.