Changes in rat liver and adipose tissue lipogenesis after single lethal X-irradiation: modification by the restricted food intake

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Sedlakova, A; Ahlers, I; Praslicka, M [Univerzita P.J. Safarika, Kosice (Czechoslovakia). Katedra Vseobecnej Biologie

1981-01-01

Male rats of Wistar strain were adapted during a 4-week period to the nutritional regimes of meal feeding (MF) and ad libitum (AL) and were irradiated with the single whole-body lethal X-ray dose 14.35 Gy after 22 h of fasting. Within the intervals 1, 24, 48 and 72 h after irradiation lipogenesis changes in the liver were studied by measuring 1-/sup 14/C-acetate incorporation (74 KBq) in the total lipids, fatty acids and cholesterol, and in the white adipose tissue pieces by measuring U-/sup 14/C-glucose incorporation (74 KBq) in the total lipids, fatty acids and glyceride glycerol. Lipogenesis increased in the liver of the irradiated rats as compared with sham irradiated rats and reached the maximal values at 72 h after irradiation in AL animals and at 48 h after irradiation in MF animals. Lipogenesis in the adipose tissue decreased in the irradiated rats as compared with the sham irradiated ones and continued to decrease with the post-irradiation period. The adaptation to the nutritional regime of meal feeding markedly modified lipogenesis in the liver and the adipose tissue of the irradiated rats. Long-term fasting (before and after irradiation) was supposed to be another modifying factor in the lipogenesis changes. Lipogenesis changes in the liver depended on the MF nutritional regime.

Modeling fructose-load-induced hepatic de-novo lipogenesis by model simplification

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Richard J Allen

2017-03-01

Full Text Available Hepatic de-novo lipogenesis is a metabolic process implemented in the pathogenesis of type 2 diabetes. Clinically, the rate of this process can be ascertained by use of labeled acetate and stimulation by fructose administration. A systems pharmacology model of this process is desirable because it facilitates the description, analysis, and prediction of this experiment. Due to the multiple enzymes involved in de-novo lipogenesis, and the limited data, it is desirable to use single functional expressions to encapsulate the flux between multiple enzymes. To accomplish this we developed a novel simplification technique which uses the available information about the properties of the individual enzymes to bound the parameters of a single governing ‘transfer function’. This method should be applicable to any model with linear chains of enzymes that are well stimulated. We validated this approach with computational simulations and analytical justification in a limiting case. Using this technique we generated a simple model of hepatic de-novo lipogenesis in these experimental conditions that matched prior data. This model can be used to assess pharmacological intervention at specific points on this pathway. We have demonstrated this with prospective simulation of acetyl-CoA carboxylase inhibition. This simplification technique suggests how the constituent properties of an enzymatic chain of reactions gives rise to the sensitivity (to substrate of the pathway as a whole.

Modeling fructose-load-induced hepatic de-novo lipogenesis by model simplification.

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Allen, Richard J; Musante, Cynthia J

2017-01-01

Hepatic de-novo lipogenesis is a metabolic process implemented in the pathogenesis of type 2 diabetes. Clinically, the rate of this process can be ascertained by use of labeled acetate and stimulation by fructose administration. A systems pharmacology model of this process is desirable because it facilitates the description, analysis, and prediction of this experiment. Due to the multiple enzymes involved in de-novo lipogenesis, and the limited data, it is desirable to use single functional expressions to encapsulate the flux between multiple enzymes. To accomplish this we developed a novel simplification technique which uses the available information about the properties of the individual enzymes to bound the parameters of a single governing 'transfer function'. This method should be applicable to any model with linear chains of enzymes that are well stimulated. We validated this approach with computational simulations and analytical justification in a limiting case. Using this technique we generated a simple model of hepatic de-novo lipogenesis in these experimental conditions that matched prior data. This model can be used to assess pharmacological intervention at specific points on this pathway. We have demonstrated this with prospective simulation of acetyl-CoA carboxylase inhibition. This simplification technique suggests how the constituent properties of an enzymatic chain of reactions gives rise to the sensitivity (to substrate) of the pathway as a whole.

Nutrigenomics and Beef Quality: A Review about Lipogenesis

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Marcio M. Ladeira

2016-06-01

Full Text Available The objective of the present review is to discuss the results of published studies that show how nutrition affects the expression of genes involved in lipid metabolism and how diet manipulation might change marbling and composition of fat in beef. Several key points in the synthesis of fat in cattle take place at the molecular level, and the association of nutritional factors with the modulation of this metabolism is one of the recent targets of nutrigenomic research. Within this context, special attention has been paid to the study of nuclear receptors associated with fatty acid metabolism. Among the transcription factors involved in lipid metabolism, the peroxisome proliferator-activated receptors (PPARs and sterol regulatory element-binding proteins (SREBPs stand out. The mRNA synthesis of these transcription factors is regulated by nutrients, and their metabolic action might be potentiated by diet components and change lipogenesis in muscle. Among the options for dietary manipulation with the objective to modulate lipogenesis, the use of different sources of polyunsaturated fatty acids, starch concentrations, forage ratios and vitamins stand out. Therefore, special care must be exercised in feedlot feed management, mainly when the goal is to produce high marbling beef.

Energy and protein relations in the broiler chicken. 4. Role of sex, line and substrate on in vitro lipogenesis

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Rosebrough, R.W.; Steele, N.C.; McMurtry, J.P.; Richards, M.P.; Mitchell, A.D.; Calvert, C.C.

1986-01-01

Experiments were conducted with dwarf (dw) and normal lines of chickens to determine the effect of sex, diet and line on lipogenesis in the 28-day-old chick. The chicks were fed diets containing 12, 18, 23 and 30% protein. In the first experiment, in vitro lipogenesis (incorporation of [2- 14 C] sodium acetate into hepatic fatty acids) as well as growth from 7 to 28 days of age were determined in males and females of both lines. In the second experiment, only males and females of the dwarf line were fed to determine the relative contribution of acetate and pyruvate to in vitro lipogenesis (incorporation of either [2- 14 C] sodium acetate or [2- 14 C) pyruvate into hepatic fatty acids). Chicks of the dwarf line were smaller than were those of the normal line. Females of both lines were smaller than males. In vitro lipogenesis was lower in the dwarf line; however the rate for both sexes within a given line was equal. An increase in the dietary protein decreased in vitro lipogenesis in both lines. The use of pyruvate as an in vitro precursor indicated that the regulation of lipid and carbohydrate metabolism may be an integrated process involving pyruvate carboxylation and subsequent flux of pyruvate carbon into either glucose or fatty acids. Based on the data presented, there is no evidence to assume, that the dwarf gene per se influences lipogenesis

Modulation of adipocyte lipogenesis by octanoate: involvement of reactive oxygen species

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Han Jianrong

2006-07-01

Full Text Available Abstract Background Octanoate is a medium-chain fatty acid (MCFA that is rich in milk and tropical dietary lipids. It also accounts for 70% of the fatty acids in commercial medium chain triglycerides (MCT. Use of MCT for weight control tracks back to early 1950s and is highlighted by recent clinical trials. The molecular mechanisms of the weight reduction effect remain not completely understood. The findings of significant amounts of MCFA in adipose tissue in MCT-fed animals and humans suggest a direct influence of MCFA on fat cell functions. Methods 3T3-L1 adipocytes were treated with octanoate in a high glucose culture medium supplemented with 10% fetal bovine serum and 170 nM insulin. The effects on lipogenesis, fatty acid oxidation, cellular concentration of reactive oxygen species (ROS, and the expression and activity of peroxisome proliferator receptor gamma (PPARγ and its associated lipogenic genes were assessed. In selected experiments, long-chain fatty acid oleate, PPARγ agonist troglitazone, and antioxidant N-acetylcysteine were used in parallel. Effects of insulin, L-carnitine, and etomoxir on β-oxidation were also measured. Results β-oxidation of octanoate was primarily independent of CPT-I. Treatment with octanoate was linked to an increase in ROS in adipocytes, a decrease in triglyceride synthesis, and reduction of lipogenic gene expression. Co-treatment with troglitazone, N-acetylcysteine, or over-expression of glutathione peroxidase largely reversed the effects of octanoate. Conclusion These findings suggest that octanoate-mediated inactivation of PPARγ might contribute to the down regulation of lipogenic genes in adipocytes, and ROS appears to be involved as a mediator in this process.

Differential effects of acute and chronic fructose administration on pyruvate dehydrogenase activity and lipogenesis

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Wilson, L.

1988-01-01

These studies were undertaken to distinguish between the acute and chronic effects of fructose administration. In vivo, liver lipogenesis, as measured by 3 H 2 O incorporation, was greater in rats fed 60% fructose than in their glucose fed controls. Both fructose feeding, and fructose feeding plus intraperitoneal fructose injection increased the activities of 6-phosphogluconate dehydrogenase and malic enzyme. Liver PDH activity was increased by fructose feeding, and was increased even more by fructose feeding and injection of fructose, but this was not associated with any changes in hepatic ATP concentrations

The amine oxidase inhibitor phenelzine limits lipogenesis in adipocytes without inhibiting insulin action on glucose uptake.

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Carpéné, Christian; Grès, Sandra; Rascalou, Simon

2013-06-01

The antidepressant phenelzine is a monoamine oxidase inhibitor known to inhibit various other enzymes, among them semicarbazide-sensitive amine oxidase (currently named primary amine oxidase: SSAO/PrAO), absent from neurones but abundant in adipocytes. It has been reported that phenelzine inhibits adipocyte differentiation of cultured preadipocytes. To further explore the involved mechanisms, our aim was to study in vitro the acute effects of phenelzine on de novo lipogenesis in mature fat cells. Therefore, glucose uptake and incorporation into lipid were measured in mouse adipocytes in response to phenelzine, other hydrazine-based SSAO/PrAO-inhibitors, and reference agents. None of the inhibitors was able to impair the sevenfold activation of 2-deoxyglucose uptake induced by insulin. Phenelzine did not hamper the effect of lower doses of insulin. However, insulin-stimulated glucose incorporation into lipids was dose-dependently inhibited by phenelzine and pentamidine, but not by semicarbazide or BTT2052. In contrast, all these SSAO/PrAO inhibitors abolished the transport and lipogenesis stimulation induced by benzylamine. These data indicate that phenelzine does not inhibit glucose transport, the first step of lipogenesis, but inhibits at 100 μM the intracellular triacylglycerol assembly, consistently with its long-term anti-adipogenic effect and such rapid action was not found with all the hydrazine derivatives tested. Therefore, the alterations of body weight control consecutive to the use of this antidepressant drug might be not only related to central effects on food intake/energy expenditure, but could also depend on its direct action in adipocytes. Nonetheless, phenelzine antilipogenic action is not merely dependent on SSAO/PrAO inhibition.

Maternal dietary free or bound fructose diversely influence developmental programming of lipogenesis.

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Yuruk, Armagan Aytug; Nergiz-Unal, Reyhan

2017-12-01

Maternal dietary choices throughout preconception, pregnancy, and lactation irreversibly affect the development of fetal tissues and organs, known as fetal programming. Recommendations tend to emphasize reducing added sugars. However, the impact of maternal dietary free or bound fructose in added sugars on developmental programming of lipogenesis is unknown. Virgin Sprague-Dawley rats were randomly divided into five groups. Rats were given feed and plain water (control) or water containing maltodextrin (vehicle), fructose, high-fructose corn syrup (HFCS) containing 55% fructose, sucrose (20% w/v) for 12 weeks before mating and throughout the pregnancy and lactation periods. Body weight, water, and feed intake were measured throughout the study. At the end of the lactation period, blood was drawn to determine the fasting levels of glucose, insulin, triglycerides, and non-esterified fatty acids (NEFA) in blood. Triglycerides and acetyl Co-A Carboxylase-1 (ACC1) levels in livers were analyzed, and insulin resistance was calculated. The energy intake of dams in the HFCS group was higher than in the fructose group, while weight gain was less in the HFCS group than in the fructose group. HFCS resulted in greater insulin resistance in dams, whereas free fructose had a robust effect on the fetal programming of insulin resistance. Free fructose and HFCS in the maternal diet increased blood and liver triglycerides and NEFA content in pups. Furthermore, fructose and HFCS exposure increased phosphorylated ACC1 as compared to maltodextrin and control, indicating greater fatty acid synthesis in pups and dams. Different types of added sugar in the maternal diet have different metabolic effects on the developmental programming of lipogenesis. Consequently, high fructose intake via processed foods may increase the risk for chronic diseases, and free fructose might contribute to developmental programming of chronic diseases more than bound fructose.

Fructose Consumption, Lipogenesis, and Non-Alcoholic Fatty Liver Disease.

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Ter Horst, Kasper W; Serlie, Mireille J

2017-09-06

Increased fructose consumption has been suggested to contribute to non-alcoholic fatty liver disease (NAFLD), dyslipidemia, and insulin resistance, but a causal role of fructose in these metabolic diseases remains debated. Mechanistically, hepatic fructose metabolism yields precursors that can be used for gluconeogenesis and de novo lipogenesis (DNL). Fructose-derived precursors also act as nutritional regulators of the transcription factors, including ChREBP and SREBP1c, that regulate the expression of hepatic gluconeogenesis and DNL genes. In support of these mechanisms, fructose intake increases hepatic gluconeogenesis and DNL and raises plasma glucose and triglyceride levels in humans. However, epidemiological and fructose-intervention studies have had inconclusive results with respect to liver fat, and there is currently no good human evidence that fructose, when consumed in isocaloric amounts, causes more liver fat accumulation than other energy-dense nutrients. In this review, we aim to provide an overview of the seemingly contradicting literature on fructose and NAFLD. We outline fructose physiology, the mechanisms that link fructose to NAFLD, and the available evidence from human studies. From this framework, we conclude that the cellular mechanisms underlying hepatic fructose metabolism will likely reveal novel targets for the treatment of NAFLD, dyslipidemia, and hepatic insulin resistance. Finally, fructose-containing sugars are a major source of excess calories, suggesting that a reduction of their intake has potential for the prevention of NAFLD and other obesity-related diseases.

Resveratrol inhibits LXRα-dependent hepatic lipogenesis through novel antioxidant Sestrin2 gene induction

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Jin, So Hee; Yang, Ji Hye; Shin, Bo Yeon; Seo, Kyuhwa; Shin, Sang Mi [College of Pharmacy, Chosun University, Gwangju 501-759 (Korea, Republic of); Cho, Il Je, E-mail: skek023@dhu.ac.kr [MRC-GHF, College of Korean Medicine, Daegu Haany University, Gyeongsan, Gyeongsangbukdo 712-715 (Korea, Republic of); Ki, Sung Hwan, E-mail: shki@chosun.ac.kr [College of Pharmacy, Chosun University, Gwangju 501-759 (Korea, Republic of)

2013-08-15

Liver X receptor-α (LXRα), a member of the nuclear receptor superfamily of ligand-activated transcription factors, regulates de novo fatty acid synthesis that leads to stimulate hepatic steatosis. Although, resveratrol has beneficial effects on metabolic disease, it is not known whether resveratrol affects LXRα-dependent lipogenic gene expression. This study investigated the effect of resveratrol in LXRα-mediated lipogenesis and the underlying molecular mechanism. Resveratrol inhibited the ability of LXRα to activate sterol regulatory element binding protein-1c (SREBP-1c) and thereby inhibited target gene expression in hepatocytes. Moreover, resveratrol decreased LXRα–RXRα DNA binding activity and LXRE-luciferase transactivation. Resveratrol is known to activate Sirtuin 1 (Sirt1) and AMP-activated protein kinase (AMPK), although its precise mechanism of action remains controversial. We found that the ability of resveratrol to repress T0901317-induced SREBP-1c expression was not dependent on AMPK and Sirt1. It is well established that hepatic steatosis is associated with antioxidant and redox signaling. Our data showing that expression of Sestrin2 (Sesn2), which is a novel antioxidant gene, was significantly down-regulated in the livers of high-fat diet-fed mice. Moreover, resveratrol up-regulated Sesn2 expression, but not Sesn1 and Sesn3. Sesn2 overexpression repressed LXRα-activated SREBP-1c expression and LXRE-luciferase activity. Finally, Sesn2 knockdown using siRNA abolished the effect of resveratrol in LXRα-induced FAS luciferase gene transactivation. We conclude that resveratrol affects Sesn2 gene induction and contributes to the inhibition of LXRα-mediated hepatic lipogenesis. - Highlights: • We investigated the effect of resveratrol in LXRα-mediated lipogenesis. • Resveratrol attenuated the ability of the LXRα-mediated lipogenic gene expression. • Resveratrol’s effects on T090-induced lipogenesis is not dependent on Sirt1 or AMPK. �

Resveratrol inhibits LXRα-dependent hepatic lipogenesis through novel antioxidant Sestrin2 gene induction

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Jin, So Hee; Yang, Ji Hye; Shin, Bo Yeon; Seo, Kyuhwa; Shin, Sang Mi; Cho, Il Je; Ki, Sung Hwan

2013-01-01

Liver X receptor-α (LXRα), a member of the nuclear receptor superfamily of ligand-activated transcription factors, regulates de novo fatty acid synthesis that leads to stimulate hepatic steatosis. Although, resveratrol has beneficial effects on metabolic disease, it is not known whether resveratrol affects LXRα-dependent lipogenic gene expression. This study investigated the effect of resveratrol in LXRα-mediated lipogenesis and the underlying molecular mechanism. Resveratrol inhibited the ability of LXRα to activate sterol regulatory element binding protein-1c (SREBP-1c) and thereby inhibited target gene expression in hepatocytes. Moreover, resveratrol decreased LXRα–RXRα DNA binding activity and LXRE-luciferase transactivation. Resveratrol is known to activate Sirtuin 1 (Sirt1) and AMP-activated protein kinase (AMPK), although its precise mechanism of action remains controversial. We found that the ability of resveratrol to repress T0901317-induced SREBP-1c expression was not dependent on AMPK and Sirt1. It is well established that hepatic steatosis is associated with antioxidant and redox signaling. Our data showing that expression of Sestrin2 (Sesn2), which is a novel antioxidant gene, was significantly down-regulated in the livers of high-fat diet-fed mice. Moreover, resveratrol up-regulated Sesn2 expression, but not Sesn1 and Sesn3. Sesn2 overexpression repressed LXRα-activated SREBP-1c expression and LXRE-luciferase activity. Finally, Sesn2 knockdown using siRNA abolished the effect of resveratrol in LXRα-induced FAS luciferase gene transactivation. We conclude that resveratrol affects Sesn2 gene induction and contributes to the inhibition of LXRα-mediated hepatic lipogenesis. - Highlights: • We investigated the effect of resveratrol in LXRα-mediated lipogenesis. • Resveratrol attenuated the ability of the LXRα-mediated lipogenic gene expression. • Resveratrol’s effects on T090-induced lipogenesis is not dependent on Sirt1 or AMPK. �

Functional overexpression and characterization of lipogenesis-related genes in the oleaginous yeast Yarrowia lipolytica.

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Silverman, Andrew M; Qiao, Kangjian; Xu, Peng; Stephanopoulos, Gregory

2016-04-01

Single cell oil (SCO) is an attractive energy source due to scalability, utilization of low-cost renewable feedstocks, and type of product(s) made. Engineering strains capable of producing high lipid titers and yields is crucial to the economic viability of these processes. However, lipid synthesis in cells is a complex phenomenon subject to multiple layers of regulation, making gene target identification a challenging task. In this study, we aimed to identify genes in the oleaginous yeast Yarrowia lipolytica whose overexpression enhances lipid production by this organism. To this end, we examined the effect of the overexpression of a set of 44 native genes on lipid production in Y. lipolytica, including those involved in glycerolipid synthesis, fatty acid synthesis, central carbon metabolism, NADPH generation, regulation, and metabolite transport and characterized each resulting strain's ability to produce lipids growing on both glucose and acetate as a sole carbon source. Our results suggest that a diverse subset of genes was effective at individually influencing lipid production in Y. lipolytica, sometimes in a substrate-dependent manner. The most productive strain on glucose overexpressed the diacylglycerol acyltransferase DGA2 gene, increasing lipid titer, cellular content, and yield by 236, 165, and 246 %, respectively, over our control strain. On acetate, our most productive strain overexpressed the acylglycerol-phosphate acyltransferase SLC1 gene, with a lipid titer, cellular content, and yield increase of 99, 91, and 151 %, respectively, over the control strain. Aside from genes encoding enzymes that directly catalyze the reactions of lipid synthesis, other ways by which lipogenesis was increased in these cells include overexpressing the glycerol-3-phosphate dehydrogenase (GPD1) gene to increase production of glycerol head groups and overexpressing the 6-phosphogluconolactonase (SOL3) gene from the oxidative pentose phosphate pathway to increase NADPH

Dapper1 attenuates hepatic gluconeogenesis and lipogenesis by activating PI3K/Akt signaling.

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Kuang, Jian-Ren; Zhang, Zhi-Hui; Leng, Wei-Ling; Lei, Xiao-Tian; Liang, Zi-Wen

2017-05-15

Studies have shown that hepatic insulin resistance, a disorder of glucose and lipid metabolism, plays a vital role in type 2 diabetes (T2D). To clarify the function of Dapper1 in glucose and lipid metabolism in the liver, we investigated the relationships between Dapper1 and adenosine triphosphate (ATP)- and Ca 2+ -mediated activation of PI3K/Akt. We observed a reduction in hepatic Dapper1 in db/db (mice that are homozygous for a spontaneous diabetes mutation) and HFD-induced diabetic mice with T2D. Hepatic overexpression of Dapper1 improved hyperglycemia, insulin resistance, and fatty liver. It also increased Akt (pAkt) signaling and repressed both gluconeogenesis and lipogenesis. Conversely, Ad-shDapper1-induced knockdown of hepatic Dapper1 promoted gluconeogenesis and lipogenesis. Furthermore, Dapper1 activated PI3K p110α/Akt in an insulin-independent manner by inducing ATP production and secretion in vitro. Blockade of P2 ATP receptors, the downstream phospholipase C (PLC), or the inositol triphosphate receptor (IP3R all reduced the Dapper1-induced increase in cytosolic free calcium and Dapper1-mediated PI3K/Akt activation, as did removal of calcium in the medium. In conclusion, Dapper1 attenuates hepatic gluconeogenesis and lipogenesis in T2D. Copyright © 2017 Elsevier B.V. All rights reserved.

SH2 domain-containing inositol 5-phosphatase (SHIP2) regulates de-novo lipogenesis and secretion of apoB100 containing lipoproteins in HepG2 cells.

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Gorgani-Firuzjaee, Sattar; Khatami, Shohreh; Adeli, Khosrow; Meshkani, Reza

2015-09-04

Hepatic de-novo lipogenesis and production of triglyceride rich VLDL are regulated via the phosphoinositide 3-kinase cascade, however, the role of a negative regulator of this pathway, the SH2 domain-containing inositol 5-phosphatase (SHIP2) in this process, remains unknown. In the present study, we investigated the molecular link between SHIP2 expression and metabolic dyslipidemia using overexpression or suppression of SHIP2 gene in HepG2 cells. The results showed that overexpression of the wild type SHIP2 gene (SHIP2-WT) led to a higher total lipid content (28%) compared to control, whereas overexpression of the dominant negative SHIP2 gene (SHIP2-DN) reduced total lipid content in oleate treated cells by 40%. Overexpression of SHIP2-WT also led to a significant increase in both secretion of apoB100 containing lipoproteins and de-novo lipogenesis, as demonstrated by an enhancement in secreted apoB100 and MTP expression, increased intra and extracellular triglyceride levels and enhanced expression of lipogenic genes such as SREBP1c, FAS and ACC. On the other hand, overexpression of the SHIP2-DN gene prevented oleate-induced de-novo lipogenesis and secretion of apoB100 containing lipoproteins in HepG2 cells. Collectively, these findings suggest that SHIP2 expression level is a key determinant of hepatic lipogenesis and lipoprotein secretion, and its inhibition could be considered as a potential target for treatment of dyslipidemia. Copyright © 2015 Elsevier Inc. All rights reserved.

Green Tea Polyphenol Epigallocatechin-3-Gallate Enhance Glycogen Synthesis and Inhibit Lipogenesis in Hepatocytes

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Jane J. Y. Kim

2013-01-01

Full Text Available The beneficial effects of green tea polyphenols (GTP against metabolic syndrome and type 2 diabetes by suppressing appetite and nutrient absorption have been well reported. However the direct effects and mechanisms of GTP on glucose and lipid metabolism remain to be elucidated. Since the liver is an important organ involved in glucose and lipid metabolism, we examined the effects and mechanisms of GTP on glycogen synthesis and lipogenesis in HepG2 cells. Concentrations of GTP containing 68% naturally occurring (−-epigallocatechin-3-gallate (EGCG were incubated in HepG2 cells with high glucose (30 mM under 100 nM of insulin stimulation for 24 h. GTP enhanced glycogen synthesis in a dose-dependent manner. 10 μM of EGCG significantly increased glycogen synthesis by 2fold (P<0.05 compared with insulin alone. Western blotting revealed that phosphorylation of Ser9 glycogen synthase kinase 3β and Ser641 glycogen synthase was significantly increased in GTP-treated HepG2 cells compared with nontreated cells. 10 μM of EGCG also significantly inhibited lipogenesis (P<0.01. We further demonstrated that this mechanism involves enhanced expression of phosphorylated AMP-activated protein kinase α and acetyl-CoA carboxylase in HepG2 cells. Our results showed that GTP is capable of enhancing insulin-mediated glucose and lipid metabolism by regulating enzymes involved in glycogen synthesis and lipogenesis.

Differential effects of high-carbohydrate and high-fat diets on hepatic lipogenesis in rats.

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Ferramosca, Alessandra; Conte, Annalea; Damiano, Fabrizio; Siculella, Luisa; Zara, Vincenzo

2014-06-01

Hepatic fatty acid synthesis is influenced by several nutritional and hormonal factors. In this study, we have investigated the effects of distinct experimental diets enriched in carbohydrate or in fat on hepatic lipogenesis. Male Wistar rats were divided into four groups and fed distinct experimental diets enriched in carbohydrates (70% w/w) or in fat (20 and 35% w/w). Activity and expression of the mitochondrial citrate carrier and of the cytosolic enzymes acetyl-CoA carboxylase and fatty acid synthetase were analyzed through the study with assessments at 0, 1, 2, 4, and 6 weeks. Liver lipids and plasma levels of lipids, glucose, and insulin were assayed in parallel. Whereas the high-carbohydrate diet moderately stimulated hepatic lipogenesis, a strong inhibition of this anabolic pathway was found in animals fed high-fat diets. This inhibition was time-dependent and concentration-dependent. Moreover, whereas the high-carbohydrate diet induced an increase in plasma triglycerides, the high-fat diets determined an accumulation of triglycerides in liver. An increase in the plasmatic levels of glucose and insulin was observed in all cases. The excess of sucrose in the diet is converted into fat that is distributed by bloodstream in the organism in the form of circulating triglycerides. On the other hand, a high amount of dietary fat caused a strong inhibition of lipogenesis and a concomitant increase in the level of hepatic lipids, thereby highlighting, in these conditions, the role of liver as a reservoir of exogenous fat.

Rab18 dynamics in adipocytes in relation to lipogenesis, lipolysis and obesity.

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Marina R Pulido

Full Text Available Lipid droplets (LDs are organelles that coordinate lipid storage and mobilization, both processes being especially important in cells specialized in managing fat, the adipocytes. Proteomic analyses of LDs have consistently identified the small GTPase Rab18 as a component of the LD coat. However, the specific contribution of Rab18 to adipocyte function remains to be elucidated. Herein, we have analyzed Rab18 expression, intracellular localization and function in relation to the metabolic status of adipocytes. We show that Rab18 production increases during adipogenic differentiation of 3T3-L1 cells. In addition, our data show that insulin induces, via phosphatidylinositol 3-kinase (PI3K, the recruitment of Rab18 to the surface of LDs. Furthermore, Rab18 overexpression increased basal lipogenesis and Rab18 silencing impaired the lipogenic response to insulin, thereby suggesting that this GTPase promotes fat accumulation in adipocytes. On the other hand, studies of the β-adrenergic receptor agonist isoproterenol confirmed and extended previous evidence for the participation of Rab18 in lipolysis. Together, our data support the view that Rab18 is a common mediator of lipolysis and lipogenesis and suggests that the endoplasmic reticulum (ER is the link that enables Rab18 action on these two processes. Finally, we describe, for the first time, the presence of Rab18 in human adipose tissue, wherein the expression of this GTPase exhibits sex- and depot-specific differences and is correlated to obesity. Taken together, these findings indicate that Rab18 is involved in insulin-mediated lipogenesis, as well as in β-adrenergic-induced lipolysis, likely facilitating interaction of LDs with ER membranes and the exchange of lipids between these compartments. A role for Rab18 in the regulation of adipocyte biology under both normal and pathological conditions is proposed.

Supplementation of glycerol or fructose via drinking water to grazing lambs on tissue glycogen level and lipogenesis.

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Volpi-Lagreca, G; Duckett, S K

2017-06-01

Lambs ( = 18; 40.1 ± 7.4 kg BW) were used to assess supplementation of glycerol or fructose via drinking water on growth, tissue glycogen levels, postmortem glycolysis, and lipogenesis. Lambs were blocked by BW and allocated to alfalfa paddocks (2 lambs/paddock and 3 paddocks/treatment). Each paddock within a block was assigned randomly to drinking water treatments for 30 d: 1) control (CON), 2) 120 g fructose/L of drinking water (FRU), or 3) 120 g glycerol/L of drinking water (GLY). Lambs grazed alfalfa with free access to water treatments for 28 d and then were fasted in indoor pens for a final 2 d with access to only water treatments. Data were analyzed using the MIXED procedure of SAS with water treatment and time (when appropriate) in the model. During the 28-d grazing period, ADG was greater ( glycogen content × postmortem time was significant ( = 0.003) in LM and semitendinosus (ST) muscles. Glycogen content in the LM was greater ( Glycogen content in ST did not differ between treatments ( > 0.05). Liver glycogen content was over 14-fold greater ( glycogen branching enzyme in the liver. Overall, glycerol supplementation improved growth, reduced BW shrink during fasting, increased glycogen content in muscle and the liver, and stimulated de novo lipogenesis.

Intelligent control system Cellular Robotics Approach to Nuclear Plant control and maintenance

International Nuclear Information System (INIS)

Fukuda, Toshio; Sekiyama, Kousuke; Xue Guoqing; Ueyama, Tsuyoshi.

1994-01-01

This paper presents the concept of Cellular Robotic System (CEBOT) and describe the strategy of a distributed sensing, control and planning as a Cellular Robotics Approach to the Nuclear Plant control and maintenance. Decentralized System is effective in large plant and The CEBOT possesses desirable features for realization of Nuclear Plant control and maintenance because of its flexibility and adaptability. Also, as related on going research work, self-organizing manipulator and communication issues are mentioned. (author)

Calorie restricted high protein diets downregulate lipogenesis and lower intrahepatic triglyceride concentrations in male rats

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The purpose of this investigation was to assess the influence of calorie restriction (CR) alone, higher-protein/lower-carbohydrate intake alone, and combined CR higher-protein/lower-carbohydrate intake on glucose homeostasis, hepatic de novo lipogenesis (DNL), and intrahepatic triglycerides. Twelve-...

Human hepatic lipase overexpression in mice induces hepatic steatosis and obesity through promoting hepatic lipogenesis and white adipose tissue lipolysis and fatty acid uptake.

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Lídia Cedó

Full Text Available Human hepatic lipase (hHL is mainly localized on the hepatocyte cell surface where it hydrolyzes lipids from remnant lipoproteins and high density lipoproteins and promotes their hepatic selective uptake. Furthermore, hepatic lipase (HL is closely associated with obesity in multiple studies. Therefore, HL may play a key role on lipid homeostasis in liver and white adipose tissue (WAT. In the present study, we aimed to evaluate the effects of hHL expression on hepatic and white adipose triglyceride metabolism in vivo. Experiments were carried out in hHL transgenic and wild-type mice fed a Western-type diet. Triglyceride metabolism studies included β-oxidation and de novo lipogenesis in liver and WAT, hepatic triglyceride secretion, and adipose lipoprotein lipase (LPL-mediated free fatty acid (FFA lipolysis and influx. The expression of hHL promoted hepatic triglyceride accumulation and de novo lipogenesis without affecting triglyceride secretion, and this was associated with an upregulation of Srebf1 as well as the main genes controlling the synthesis of fatty acids. Transgenic mice also exhibited more adiposity and an increased LPL-mediated FFA influx into the WAT without affecting glucose tolerance. Our results demonstrate that hHL promoted hepatic steatosis in mice mainly by upregulating de novo lipogenesis. HL also upregulated WAT LPL and promoted triglyceride-rich lipoprotein hydrolysis and adipose FFA uptake. These data support the important role of hHL in regulating hepatic lipid homeostasis and confirm the broad cardiometabolic role of HL.

Human hepatic lipase overexpression in mice induces hepatic steatosis and obesity through promoting hepatic lipogenesis and white adipose tissue lipolysis and fatty acid uptake.

Science.gov (United States)

Cedó, Lídia; Santos, David; Roglans, Núria; Julve, Josep; Pallarès, Victor; Rivas-Urbina, Andrea; Llorente-Cortes, Vicenta; Laguna, Joan Carles; Blanco-Vaca, Francisco; Escolà-Gil, Joan Carles

2017-01-01

Human hepatic lipase (hHL) is mainly localized on the hepatocyte cell surface where it hydrolyzes lipids from remnant lipoproteins and high density lipoproteins and promotes their hepatic selective uptake. Furthermore, hepatic lipase (HL) is closely associated with obesity in multiple studies. Therefore, HL may play a key role on lipid homeostasis in liver and white adipose tissue (WAT). In the present study, we aimed to evaluate the effects of hHL expression on hepatic and white adipose triglyceride metabolism in vivo. Experiments were carried out in hHL transgenic and wild-type mice fed a Western-type diet. Triglyceride metabolism studies included β-oxidation and de novo lipogenesis in liver and WAT, hepatic triglyceride secretion, and adipose lipoprotein lipase (LPL)-mediated free fatty acid (FFA) lipolysis and influx. The expression of hHL promoted hepatic triglyceride accumulation and de novo lipogenesis without affecting triglyceride secretion, and this was associated with an upregulation of Srebf1 as well as the main genes controlling the synthesis of fatty acids. Transgenic mice also exhibited more adiposity and an increased LPL-mediated FFA influx into the WAT without affecting glucose tolerance. Our results demonstrate that hHL promoted hepatic steatosis in mice mainly by upregulating de novo lipogenesis. HL also upregulated WAT LPL and promoted triglyceride-rich lipoprotein hydrolysis and adipose FFA uptake. These data support the important role of hHL in regulating hepatic lipid homeostasis and confirm the broad cardiometabolic role of HL.

Physiological activities of the combination of fish oil and α-lipoic acid affecting hepatic lipogenesis and parameters related to oxidative stress in rats.

Science.gov (United States)

Ide, Takashi

2018-06-01

We studied the combined effect of fish oil and α-lipoic acid on hepatic lipogenesis and fatty acid oxidation and parameters of oxidative stress in rats fed lipogenic diets high in sucrose. A control diet contained a saturated fat (palm oil) that gives high rate of hepatic lipogenesis. Male Sprague-Dawley rats were fed diets supplemented with 0 or 2.5 g/kg α-lipoic acid and containing 0, 20, or 100 g/kg fish oil, for 21 days. α-Lipoic acid significantly reduced food intake during 0-8 days but not the later period of the experiment. Fish oil and α-lipoic acid decreased serum lipid concentrations and their combination further decreased the parameters in an additive fashion. The combination of fish oil and α-lipoic acid decreased the activity and mRNA levels of hepatic lipogenic enzymes in an additive fashion. Fish oil increased the parameters of hepatic fatty acid oxidation enzymes. α-Lipoic acid appeared to antagonize the stimulating effects of fish oil of fatty acid oxidation through reductions in the activity of some fatty acid oxidation enzymes. α-Lipoic acid attenuated fish oil-dependent increases in serum and liver malondialdehyde levels, and this compound also reduced the serum 8-hydroxy-2'-deoxyguanosine level. α-Lipoic acid affected various parameters related to the antioxidant system; fish oil also affected some of the parameters. The combination of fish oil and α-lipoic acid effectively reduced serum lipid levels through the additive down-regulation of hepatic lipogenesis. α-Lipoic acid was effective in attenuating fish oil-mediated oxidative stress.

Adiposity, lipogenesis, and fatty acid composition of subcutaneous and intramuscular adipose tissues of Brahman and Angus crossbred cattle.

Science.gov (United States)

Campbell, E M G; Sanders, J O; Lunt, D K; Gill, C A; Taylor, J F; Davis, S K; Riley, D G; Smith, S B

2016-04-01

The objective of this study was to demonstrate differences in aspects of adipose tissue cellularity, lipid metabolism, and fatty and cholesterol composition in Angus and Brahman crossbred cattle. We hypothesized that in vitro measures of lipogenesis would be greater in three-fourths Angus progeny than in three-fourths Brahman progeny, especially in intramuscular (i.m.) adipose tissue. Progeny ( = 227) were fed a standard, corn-based diet for approximately 150 d before slaughter. Breed was considered to be the effect of interest and was forced into the model. There were 9 breed groups including all 4 kinds of three-fourths Angus calves: Angus bulls Angus-sired F cows ( = 32), Angus bulls Brahman-sired F cows ( = 20), Brahman-sired F bulls Angus cows ( = 24), and Angus-sired F bulls Angus cows ( = 20). There were all 4 kinds of three-fourths Brahman calves: Brahman bulls Brahman-sired F cows ( = 21), Brahman bulls Angus-sired F cows ( = 43), Brahman-sired F bulls Brahman cows ( = 26), and Angus-sired F bulls Brahman cows ( = 13). Additionally, F calves (one-half Brahman and one-half Angus) were produced only from Brahman-sired F bulls Angus-sired F cows ( = 28). Contrasts were calculated when breed was an important fixed effect, using the random effect family(breed) as the error term. Most contrasts were nonsignificant ( > 0.10). Those that were significant ( Angus > F, three-fourths Brahman > F, and three-fourths crossbred progeny combined > F), s.c. adipocyte volume (three-fourths Angus > F and three-fourths bloods combined > F), lipogenesis from acetate in s.c. adipose tissue (three-fourths Brahman calves from Brahman dams > three-fourths Brahman calves from F dams), and percentage 18:3-3 in s.c. adipose tissue (three-fourths Brahman calves from Brahman-sired F dams Angus-sired F dams). Intramuscular adipocyte volume ( Angus cattle. Additionally, several differences were observed in i.m. adipose tissue that were consistent with this being a less-developed adipose

Saponins, especially platycodin D, from Platycodon grandiflorum modulate hepatic lipogenesis in high-fat diet-fed rats and high glucose-exposed HepG2 cells

Energy Technology Data Exchange (ETDEWEB)

Hwang, Yong Pil [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Department of Pharmaceutical Engineering, International University of Korea, Jinju (Korea, Republic of); Choi, Jae Ho; Kim, Hyung Gyun; Khanal, Tilak; Song, Gye Young [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Nam, Myoung Soo [College of Agriculture and Life Sciences, Chungnam National University, Daejeon (Korea, Republic of); Lee, Hyun-Sun [Molecular Cancer Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Chung, Young Chul; Lee, Young Chun [Division of Food Science, International University of Korea, Jinju (Korea, Republic of); Jeong, Hye Gwang, E-mail: hgjeong@cnu.ac.kr [Department of Toxicology, College of Pharmacy, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

2013-03-01

AMP-activated protein kinase (AMPK) plays a central role in controlling hepatic lipid metabolism through modulating the downstream acetyl CoA carboxylase (ACC) and sterol regulatory element-binding protein-1c (SREBP-1c) pathway. Saponins, particularly platycodin D, from the roots of Platycodon grandiflorum (Changkil saponins, CKS) have a variety of pharmacological properties, including antioxidant and hepatoprotective properties. The aim of this study was to investigate the effects of CKS on hepatic lipogenesis and on the expression of genes involved in lipogenesis, and the mechanisms involved. CKS attenuated fat accumulation and the induction of the lipogenic genes encoding SREBP-1c and fatty acid synthase in the livers of HFD-fed rats and in steatotic HepG2 cells. Blood biochemical analyses and histopathological examinations showed that CKS prevented liver injury. CKS and platycodin D each increased the phosphorylation of AMPK and acetyl-CoA carboxylase in HFD-fed rats and HepG2 cells. The use of specific inhibitors showed that platycodin D activated AMPK via SIRT1/CaMKKβ in HepG2 cells. This study demonstrates that CKS or platycodin D alone can regulate hepatic lipogenesis via an AMPK-dependent signalling pathway. - Highlights: ► CKS attenuated fat accumulation in HFD-fed rats and in steatotic HepG2 cells. ► CKS and its major component, platycodin D, inhibited the levels of SREBP-1 and FAS. ► CKS and platycodin D increased the phosphorylation of AMPK and ACC. ► Platycodin D activated AMPK via SIRT1/CaMKKβ in HepG2 cells.

Force control for mechanoinduction of impedance variation in cellular organisms

International Nuclear Information System (INIS)

Nam, Joo Hoo; Chen, Peter C Y; Lu, Zhe; Luo, Hong; Lin, Wei; Ge, Ruowen

2010-01-01

Constantly exposed to various forms of mechanical forces inherent in their physical environment (such as gravity, stress induced by fluid flow or cell–cell interactions, etc), cellular organisms sense such forces and convert them into biochemical signals through the processes of mechanosensing and mechanotransduction that eventually lead to biological changes. The effect of external forces on the internal structures and activities in a cellular organism may manifest in changes its physical properties, such as impedance. Studying variation in the impedance of a cellular organism induced by the application of an external mechanical force represents a meaningful endeavor (from a biosystems perspective) in exploring the complex mechanosensing and mechanotransduction mechanisms that govern the behavior of a cellular organism under the influence of external mechanical stimuli. In this paper we describe the development of an explicit force-feedback control system for exerting an indentation force on a cellular organism while simultaneously measuring its impedance. To demonstrate the effectiveness of this force-control system, we have conducted experiments using zebrafish embryos as a test model of a cellular organism. We report experimental results demonstrating that the application of a properly controlled external force leads to a significant change in the impedance of a zebrafish embryo. These results offer support for a plausible explanation that activities of pore canals in the chorion are responsible for the observed change in impedance.

ER phospholipid composition modulates lipogenesis during feeding and in obesity.

Science.gov (United States)

Rong, Xin; Wang, Bo; Palladino, Elisa Nd; de Aguiar Vallim, Thomas Q; Ford, David A; Tontonoz, Peter

2017-10-02

Sterol regulatory element-binding protein 1c (SREBP-1c) is a central regulator of lipogenesis whose activity is controlled by proteolytic cleavage. The metabolic factors that affect its processing are incompletely understood. Here, we show that dynamic changes in the acyl chain composition of ER phospholipids affect SREBP-1c maturation in physiology and disease. The abundance of polyunsaturated phosphatidylcholine in liver ER is selectively increased in response to feeding and in the setting of obesity-linked insulin resistance. Exogenous delivery of polyunsaturated phosphatidylcholine to ER accelerated SREBP-1c processing through a mechanism that required an intact SREBP cleavage-activating protein (SCAP) pathway. Furthermore, induction of the phospholipid-remodeling enzyme LPCAT3 in response to liver X receptor (LXR) activation promoted SREBP-1c processing by driving the incorporation of polyunsaturated fatty acids into ER. Conversely, LPCAT3 deficiency increased membrane saturation, reduced nuclear SREBP-1c abundance, and blunted the lipogenic response to feeding, LXR agonist treatment, or obesity-linked insulin resistance. Desaturation of the ER membrane may serve as an auxiliary signal of the fed state that promotes lipid synthesis in response to nutrient availability.

Activation of the constitutive androstane receptor inhibits gluconeogenesis without affecting lipogenesis or fatty acid synthesis in human hepatocytes

Energy Technology Data Exchange (ETDEWEB)

Lynch, Caitlin; Pan, Yongmei; Li, Linhao [Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States); Heyward, Scott; Moeller, Timothy [Bioreclamation In Vitro Technologies, Baltimore, MD 21227 (United States); Swaan, Peter W. [Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States); Wang, Hongbing, E-mail: hwang@rx.umaryland.edu [Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201 (United States)

2014-08-15

Objective: Accumulating evidence suggests that activation of mouse constitutive androstane receptor (mCAR) alleviates type 2 diabetes and obesity by inhibiting hepatic gluconeogenesis, lipogenesis, and fatty acid synthesis. However, the role of human (h) CAR in energy metabolism is largely unknown. The present study aims to investigate the effects of selective hCAR activators on hepatic energy metabolism in human primary hepatocytes (HPH). Methods: Ligand-based structure–activity models were used for virtual screening of the Specs database ( (www.specs.net)) followed by biological validation in cell-based luciferase assays. The effects of two novel hCAR activators (UM104 and UM145) on hepatic energy metabolism were evaluated in HPH. Results: Real-time PCR and Western blotting analyses reveal that activation of hCAR by UM104 and UM145 significantly repressed the expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, two pivotal gluconeogenic enzymes, while exerting negligible effects on the expression of genes associated with lipogenesis and fatty acid synthesis. Functional experiments show that UM104 and UM145 markedly inhibit hepatic synthesis of glucose but not triglycerides in HPH. In contrast, activation of mCAR by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene, a selective mCAR activator, repressed the expression of genes associated with gluconeogenesis, lipogenesis, and fatty acid synthesis in mouse primary hepatocytes, which were consistent with previous observations in mouse model in vivo. Conclusion: Our findings uncover an important species difference between hCAR and mCAR in hepatic energy metabolism, where hCAR selectively inhibits gluconeogenesis without suppressing fatty acid synthesis. Implications: Such species selectivity should be considered when exploring CAR as a potential therapeutic target for metabolic disorders. - Highlights: • Novel hCAR activators were identified by computational and biological approaches. • The role

Activation of the constitutive androstane receptor inhibits gluconeogenesis without affecting lipogenesis or fatty acid synthesis in human hepatocytes

International Nuclear Information System (INIS)

Lynch, Caitlin; Pan, Yongmei; Li, Linhao; Heyward, Scott; Moeller, Timothy; Swaan, Peter W.; Wang, Hongbing

2014-01-01

Objective: Accumulating evidence suggests that activation of mouse constitutive androstane receptor (mCAR) alleviates type 2 diabetes and obesity by inhibiting hepatic gluconeogenesis, lipogenesis, and fatty acid synthesis. However, the role of human (h) CAR in energy metabolism is largely unknown. The present study aims to investigate the effects of selective hCAR activators on hepatic energy metabolism in human primary hepatocytes (HPH). Methods: Ligand-based structure–activity models were used for virtual screening of the Specs database ( (www.specs.net)) followed by biological validation in cell-based luciferase assays. The effects of two novel hCAR activators (UM104 and UM145) on hepatic energy metabolism were evaluated in HPH. Results: Real-time PCR and Western blotting analyses reveal that activation of hCAR by UM104 and UM145 significantly repressed the expression of glucose-6-phosphatase and phosphoenolpyruvate carboxykinase, two pivotal gluconeogenic enzymes, while exerting negligible effects on the expression of genes associated with lipogenesis and fatty acid synthesis. Functional experiments show that UM104 and UM145 markedly inhibit hepatic synthesis of glucose but not triglycerides in HPH. In contrast, activation of mCAR by 1,4-bis[2-(3,5-dichloropyridyloxy)]benzene, a selective mCAR activator, repressed the expression of genes associated with gluconeogenesis, lipogenesis, and fatty acid synthesis in mouse primary hepatocytes, which were consistent with previous observations in mouse model in vivo. Conclusion: Our findings uncover an important species difference between hCAR and mCAR in hepatic energy metabolism, where hCAR selectively inhibits gluconeogenesis without suppressing fatty acid synthesis. Implications: Such species selectivity should be considered when exploring CAR as a potential therapeutic target for metabolic disorders. - Highlights: • Novel hCAR activators were identified by computational and biological approaches. • The role

JTP-103237, a monoacylglycerol acyltransferase inhibitor, prevents fatty liver and suppresses both triglyceride synthesis and de novo lipogenesis

Directory of Open Access Journals (Sweden)

Chihiro Okuma

2015-07-01

Conclusion: In the present study, JTP-103237 prevented carbohydrate-induced fatty liver and suppressed both TG synthesis and de novo lipogenesis, suggesting MGAT inhibitor may prevent carbohydrate-induced metabolic disorders, including NAFLD, obesity and diabetes.

Consumption of resistant starch decreases postprandial lipogenesis in white adipose tissue of the rat

Directory of Open Access Journals (Sweden)

Brown Marc A

2006-09-01

Full Text Available Abstract Chronic consumption of diets high in resistant starch (RS leads to reduced fat cell size compared to diets high in digestible starch (DS in rats and increases total and meal fat oxidation in humans. The aim of the present study was to examine the rate of lipogenesis in key lipogenic organs following a high RS or DS meal. Following an overnight fast, male Wistar rats ingested a meal with an RS content of 2% or 30% of total carbohydrate and were then administered an i.p bolus of 50 μCi 3H2O either immediately or 1 hour post-meal. One hour following tracer administration, rats were sacrificed, a blood sample collected, and the liver, white adipose tissue (WAT, and gastrocnemius muscle excised and frozen until assayed for total 3H-lipid and 3H-glycogen content. Plasma triglyceride and NEFA concentrations and 3H-glycogen content did not differ between groups. In all tissues, except the liver, there was a trend for the rate of lipogenesis to be higher in the DS group than the RS group which reached significance only in WAT at 1 h (p

Evodia alkaloids suppress gluconeogenesis and lipogenesis by activating the constitutive androstane receptor.

Science.gov (United States)

Yu, Lushan; Wang, Zhangting; Huang, Minmin; Li, Yingying; Zeng, Kui; Lei, Jinxiu; Hu, Haihong; Chen, Baian; Lu, Jing; Xie, Wen; Zeng, Su

2016-09-01

The constitutive androstane receptor (CAR) is a key sensor in xenobiotic detoxification and endobiotic metabolism. Increasing evidence suggests that CAR also plays a role in energy metabolism by suppressing the hepatic gluconeogenesis and lipogenesis. In this study, we investigated the effects of two evodia alkaloids, rutaecarpine (Rut) and evodiamine (Evo), on gluconeogenesis and lipogenesis through their activation of the human CAR (hCAR). We found that both Rut and Evo exhibited anti-lipogenic and anti-gluconeogenic effects in the hyperlipidemic HepG2 cells. Both compounds can potently activate hCAR, and treatment of cells with hCAR antagonists reversed the anti-lipogenic and anti-gluconeogenic effects of Rut and Evo. The anti-gluconeogenic effect of Rut and Evo was due to the CAR-mediated inhibition of the recruitment of forkhead box O1 (FoxO1) and hepatocyte nuclear factor 4α (HNF4α) onto the phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) gene promoters. In vivo, we showed that treatment of mice with Rut improved glucose tolerance in a CAR-dependent manner. Our results suggest that the evodia alkaloids Rut and Evo may have a therapeutic potential for the treatment of hyperglycemia and type 2 diabetes. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie. Copyright © 2015 Elsevier B.V. All rights reserved.

Aberrant lipogenesis is a metabolic marker for azole-resistant candida albicans (Conference Presentation)

Science.gov (United States)

Karanja, Caroline; Hong, Weili; Younis, Waleed; Cheng, Ji-Xin; Seleem, Mohamed

2017-02-01

Candida is the single most important cause of fungal bloodstream infections worldwide causing significant mortality as high as 50%. This high mortality rate is, in part, due to the inability to rapidly diagnose and simultaneously initiate an effective antifungal therapy early in the disease process. Current culture-based diagnostics are often slow, requiring several days to complete, and are only 50% sensitive in diagnosing candidemia (Candida bloodstream infection). For every 12 hours of delay in starting correct antifungal therapy, the risk of death for a given patient with candidemia increases by 200%. To address this unmet need, we explored the potential of employing stimulated Raman Scattering (SRS) imaging to diagnose candidemia and probe metabolic differences between resistant and susceptible strain at a single cell level. Metabolism is integral to pathogenicity; microorganism have very short life cycles, and therefore only a few hours are needed to observe a full metabolic cycle. SRS imaging at C-H vibration frequency at 2850 cm-1 revealed a substantial difference in lipogenesis between the susceptible and resistant C. albicans. Treating the C. albicans with fluconazole, an antimicrobial drug that targets ergosterol biosynthesis only affected the lipogenesis in the susceptible strain. Our results show that single-cell metabolic imaging under a SRS microscope can be used for diagnose candidemia and early detection of antimicrobial susceptibility.

Induction of lipogenesis in white fat during cold exposure in mice: link to lean phenotype

Czech Academy of Sciences Publication Activity Database

Flachs, Pavel; Adamcová, Kateřina; Zouhar, Petr; Marques, C.; Janovská, Petra; Viegas, I.; Jones, J. G.; Bardová, Kristina; Svobodová, Michaela; Hansíková, Jana; Kuda, Ondřej; Rossmeisl, Martin; Liisberg, U.; Borkowska, A. G.; Kristiansen, K.; Madsen, L.; Kopecký, Jan

2017-01-01

Roč. 41, č. 3 (2017), s. 372-380 ISSN 0307-0565 R&D Projects: GA ČR(CZ) GA13-00871S; GA MŠk(CZ) 7E12073 Institutional support: RVO:67985823 Keywords : cold exposure * epididymal adipose tissue * futile substrate cycling * lipogenesis Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition OBOR OECD: Endocrinology and metabolism (including diabetes, hormones) Impact factor: 5.487, year: 2016

Dose- and type-dependent effects of long-chain fatty acids on adipogenesis and lipogenesis of bovine adipocytes.

Science.gov (United States)

Yanting, Chen; Yang, Q Y; Ma, G L; Du, M; Harrison, J H; Block, E

2018-02-01

Differentiation and lipid metabolism of adipocytes have a great influence on milk performance, health, and feed efficiency of dairy cows. The effects of dietary long-chain fatty acids (FA) on adipogenesis and lipogenesis of dairy cows are often confounded by other nutritional and physiological factors in vivo. Therefore, this study used an in vitro approach to study the effect of dose and type of long-chain FA on adipogenesis and lipogenesis of bovine adipocytes. Stromal vascular cells were isolated from adipose tissue of dairy cows and induced into mature adipocytes in the presence of various long-chain FA including myristic, palmitic, stearic, oleic, or linoleic acid. When concentrations of myristic, palmitic, and oleic acids in adipogenic mediums were 150 and 200 μM, the induced mature adipocytes had greater lipid content compared with other concentrations of FA. In addition, mature adipocytes induced at 100 μM stearic acid and 300 μM linoleic acid had the greatest content of lipid than at other concentrations. High concentrations of saturated FA were more toxic for cells than the same concentration of unsaturated FA during the induction. When commitment stage was solely treated with FA, the number of differentiated mature adipocytes was greater for oleic and linoleic acids than other FA. When the maturation stage was treated with FA, the number of mature adipocytes was not affected, but the lipid content in adipocytes was affected and ranked oleic > linoleic > myristic > stearic > palmitic. In summary, this study showed that adipogenesis and lipogenesis of bovine adipocytes were differentially affected by long-chain FA, with unsaturated FA more effective than saturated FA. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Reciprocal regulation of LXRα activity by ASXL1 and ASXL2 in lipogenesis

Energy Technology Data Exchange (ETDEWEB)

Park, Ui-Hyun; Seong, Mi-ran [Department of Bioscience and Biotechnology, Institute of Bioscience, BK21 Graduate Program, Sejong University, Seoul 143-747 (Korea, Republic of); Kim, Eun-Joo; Hur, Wonhee; Kim, Sung Woo [Department of Molecular Biology, BK21 Graduate Program, Dankook University, Gyeonggi-do 448-701 (Korea, Republic of); Yoon, Seung Kew [The Catholic University Liver Research Center and WHO Collaborating Center of Viral Hepatitis, The Catholic University, College of Medicine, Seoul 137-701 (Korea, Republic of); Um, Soo-Jong, E-mail: umsj@sejong.ac.kr [Department of Bioscience and Biotechnology, Institute of Bioscience, BK21 Graduate Program, Sejong University, Seoul 143-747 (Korea, Republic of)

2014-01-10

Highlights: •ASXL1 and ASXL2 directly interact with ligand-bound LXRα. •Ligand-induced LXRα activity is repressed by ASXL1 and activated by ASXL2. •ASXL1 and ASXL2 bind to the LXRE of the LXRα target promoter. •ASXL1 and ASXL2 reciprocally regulate lipogenesis in liver cells. -- Abstract: Liver X receptor alpha (LXRα), a member of the nuclear receptor superfamily, plays a pivotal role in hepatic cholesterol and lipid metabolism, regulating the expression of genes associated with hepatic lipogenesis. The additional sex comb-like (ASXL) family was postulated to regulate chromatin function. Here, we investigate the roles of ASXL1 and ASXL2 in regulating LXRα activity. We found that ASXL1 suppressed ligand-induced LXRα transcriptional activity, whereas ASXL2 increased LXRα activity through direct interaction in the presence of the ligand. Chromatin immunoprecipitation (ChIP) assays showed ligand-dependent recruitment of ASXLs to ABCA1 promoters, like LXRα. Knockdown studies indicated that ASXL1 inhibits, while ASXL2 increases, lipid accumulation in H4IIE cells, similar to their roles in transcriptional regulation. We also found that ASXL1 expression increases under fasting conditions, and decreases in insulin-treated H4IIE cells and the livers of high-fat diet-fed mice. Overall, these results support the reciprocal role of the ASXL family in lipid homeostasis through the opposite regulation of LXRα.

Ursodeoxycholic Acid Suppresses Lipogenesis in Mouse Liver: Possible Role of the Decrease in β-Muricholic Acid, a Farnesoid X Receptor Antagonist.

Science.gov (United States)

Fujita, Kyosuke; Iguchi, Yusuke; Une, Mizuho; Watanabe, Shiro

2017-04-01

The farnesoid X receptor (FXR) is a major nuclear receptor of bile acids; its activation suppresses sterol regulatory element-binding protein 1c (SREBP1c)-mediated lipogenesis and decreases the lipid contents in the liver. There are many reports showing that the administration of ursodeoxycholic acid (UDCA) suppresses lipogenesis and reduces the lipid contents in the liver of experimental animals. Since UDCA is not recognized as an FXR agonist, these effects of UDCA cannot be readily explained by its direct activation of FXR. We observed that the dietary administration of UDCA in mice decreased the expression levels of SREBP1c and its target lipogenic genes. Alpha- and β-muricholic acids (MCA) and cholic acid (CA) were the major bile acids in the mouse liver but their contents decreased upon UDCA administration. The hepatic contents of chenodeoxycholic acid and deoxycholic acid (DCA) were relatively low but were not changed by UDCA. UDCA did not show FXR agonistic or antagonistic potency in in vitro FXR transactivation assay. Taking these together, we deduced that the above-mentioned change in hepatic bile acid composition induced upon UDCA administration might cause the relative increase in the FXR activity in the liver, mainly by the reduction in the content of β-MCA, a farnesoid X receptor antagonist, which suggests a mechanism by which UDCA suppresses lipogenesis and decreases the lipid contents in the mouse liver.

n3 and n6 polyunsaturated fatty acids differentially modulate prostaglandin E secretion but not markers of lipogenesis in adipocytes

Directory of Open Access Journals (Sweden)

Saxton Arnold M

2009-01-01

Full Text Available Abstract A dramatic rise in the incidence of obesity in the U.S. has accelerated the search for interventions that may impact this epidemic. One recently recognized target for such intervention is adipose tissue, which secretes a variety of bioactive substances including prostaglandins. Prostaglandin E2 (PGE2 has been shown to decrease lipolysis in adipocytes, but limited studies have explored alternative mechanisms by which PGE2 might impact obesity, such as adipogenesis or lipogenesis. Studies conducted on ApcMin/+ mice indicated that selective inhibition of the cyclooxygenase (COX-2 enzyme led to significant reductions in fatty acid synthase (FAS activity in adipose tissue suggesting lipogenic effects of PGE2. To further investigate whether these lipid mediators directly regulate lipogenesis, we used 3T3-L1 adipocytes to determine the impact of eicosapentaenoic acid (EPA and celecoxib on PGE2 formation and FAS used as a lipogenic marker. Both arachidonic acid (AA and EPA dose-dependently increased PGE secretion from adipocytes. AA was expectedly more potent and exhibiting at 150 uM dose a 5-fold increase in PGE2 secretion over EPA. Despite higher secretion of PGE by EPA and AA compared to control, neither PUFA significantly altered FAS activity. By contrast both AA and EPA significantly decreased FAS mRNA levels. Addition of celecoxib, a selective COX-2 inhibitor, significantly decreased PGE2 secretion (p 2 and celecoxib further decreased the FAS activity compared to PGE2 alone or untreated controls. In conclusion, EPA-mediated inhibition of AA metabolism did not significantly alter FAS activity while both AA and EPA significantly decreased FAS mRNA expression. COX-2 inhibition significantly decreased PGE2 production resulting in a decrease in FAS activity and expression that was not reversed with the addition of exogenous PGE2, suggesting an additional mechanism that is independent of COX-2.

Characterization of the sebocyte lipid droplet proteome reveals novel potential regulators of sebaceous lipogenesis.

Science.gov (United States)

Dahlhoff, Maik; Fröhlich, Thomas; Arnold, Georg J; Müller, Udo; Leonhardt, Heinrich; Zouboulis, Christos C; Schneider, Marlon R

2015-03-01

Lipid metabolism depends on lipid droplets (LD), cytoplasmic structures surrounded by a protein-rich phospholipid monolayer. Although lipid synthesis is the hallmark of sebaceous gland cell differentiation, the LD-associated proteins of sebocytes have not been evaluated systematically. The LD fraction of SZ95 sebocytes was collected by density gradient centrifugation and associated proteins were analyzed by nanoliquid chromatography/tandem mass spectrometry. 54 proteins were significantly enriched in LD fractions, and 6 of them have not been detected previously in LDs. LD fractions contained high levels of typical LD-associated proteins as PLIN2/PLIN3, and most proteins belonged to functional categories characteristic for LD-associated proteins, indicating a reliable dataset. After confirming expression of transcripts encoding the six previously unidentified proteins by qRT-PCR in SZ95 sebocytes and in another sebocyte line (SebE6E7), we focused on two of these proteins, ALDH1A3 and EPHX4. While EPHX4 was localized almost exclusively on the surface of LDs, ALDH1A3 showed a more widespread localization that included additional cytoplasmic structures. siRNA-mediated downregulation revealed that depletion of EPHX4 increases LD size and sebaceous lipogenesis. Further studies on the roles of these proteins in sebocyte physiology and sebaceous lipogenesis may indicate novel strategies for the therapy of sebaceous gland-associated diseases such as acne. Copyright © 2014 Elsevier Inc. All rights reserved.

Chaos Control and Synchronization of Cellular Neural Network with Delays Based on OPNCL Control

International Nuclear Information System (INIS)

Qian, Tang; Xing-Yuan, Wang

2010-01-01

The problem of chaos control and complete synchronization of cellular neural network with delays is studied. Based on the open plus nonlinear closed loop (OPNCL) method, the control scheme and synchronization scheme are designed. Both the schemes can achieve the chaos control and complete synchronization of chaotic neural network respectively, and their validity is further verified by numerical simulation experiments. (general)

ER-tethered Transcription Factor CREBH Regulates Hepatic Lipogenesis, Fatty Acid Oxidation, and Lipolysis upon Metabolic Stress

OpenAIRE

Zhang, Chunbin; Wang, Guohui; Zheng, Ze; Maddipati, Krishna Rao; Zhang, Xuebao; Dyson, Gregory; Williams, Paul; Duncan, Stephen A.; Kaufman, Randal J.; Zhang, Kezhong

2012-01-01

CREBH is a liver-specific transcription factor that is localized in the endoplasmic reticulum (ER) membrane. Our previous work demonstrated that CREBH is activated by ER stress or inflammatory stimuli to induce an acute-phase hepatic inflammation. Here we demonstrate that CREBH is a key metabolic regulator of hepatic lipogenesis, fatty acid (FA) oxidation, and lipolysis under metabolic stress. Saturated FA, insulin signals, or an atherogenic high-fat diet can induce CREBH activation in the li...

Bistable switches control memory and plasticity in cellular differentiation

Science.gov (United States)

Wang, Lei; Walker, Brandon L.; Iannaccone, Stephen; Bhatt, Devang; Kennedy, Patrick J.; Tse, William T.

2009-01-01

Development of stem and progenitor cells into specialized tissues in multicellular organisms involves a series of cell fate decisions. Cellular differentiation in higher organisms is generally considered irreversible, and the idea of developmental plasticity in postnatal tissues is controversial. Here, we show that inhibition of mitogen-activated protein kinase (MAPK) in a human bone marrow stromal cell-derived myogenic subclone suppresses their myogenic ability and converts them into satellite cell-like precursors that respond to osteogenic stimulation. Clonal analysis of the induced osteogenic response reveals ultrasensitivity and an “all-or-none” behavior, hallmarks of a bistable switch mechanism with stochastic noise. The response demonstrates cellular memory, which is contingent on the accumulation of an intracellular factor and can be erased by factor dilution through cell divisions or inhibition of protein synthesis. The effect of MAPK inhibition also exhibits memory and appears to be controlled by another bistable switch further upstream that determines cell fate. Once the memory associated with osteogenic differentiation is erased, the cells regain their myogenic ability. These results support a model of cell fate decision in which a network of bistable switches controls inducible production of lineage-specific differentiation factors. A competitive balance between these factors determines cell fate. Our work underscores the dynamic nature of cellular differentiation and explains mechanistically the dual properties of stability and plasticity associated with the process. PMID:19366677

Channel Access and Power Control for Mobile Crowdsourcing in Device-to-Device Underlaid Cellular Networks

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Yue Ma

2018-01-01

Full Text Available With the access of a myriad of smart handheld devices in cellular networks, mobile crowdsourcing becomes increasingly popular, which can leverage omnipresent mobile devices to promote the complicated crowdsourcing tasks. Device-to-device (D2D communication is highly desired in mobile crowdsourcing when cellular communications are costly. The D2D cellular network is more preferable for mobile crowdsourcing than conventional cellular network. Therefore, this paper addresses the channel access and power control problem in the D2D underlaid cellular networks. We propose a novel semidistributed network-assisted power and a channel access control scheme for D2D user equipment (DUE pieces. It can control the interference from DUE pieces to the cellular user accurately and has low information feedback overhead. For the proposed scheme, the stochastic geometry tool is employed and analytic expressions are derived for the coverage probabilities of both the cellular link and D2D links. We analyze the impact of key system parameters on the proposed scheme. The Pareto optimal access threshold maximizing the total area spectral efficiency is obtained. Unlike the existing works, the performances of the cellular link and D2D links are both considered. Simulation results show that the proposed method can improve the total area spectral efficiency significantly compared to existing schemes.

Jatropha curcas Protein Concentrate Stimulates Insulin Signaling, Lipogenesis, Protein Synthesis and the PKCα Pathway in Rat Liver.

Science.gov (United States)

León-López, Liliana; Márquez-Mota, Claudia C; Velázquez-Villegas, Laura A; Gálvez-Mariscal, Amanda; Arrieta-Báez, Daniel; Dávila-Ortiz, Gloria; Tovar, Armando R; Torres, Nimbe

2015-09-01

Jatropha curcas is an oil seed plant that belongs to the Euphorbiaceae family. Nontoxic genotypes have been reported in Mexico. The purpose of the present work was to evaluate the effect of a Mexican variety of J. curcas protein concentrate (JCP) on weight gain, biochemical parameters, and the expression of genes and proteins involved in insulin signaling, lipogenesis, cholesterol and protein synthesis in rats. The results demonstrated that short-term consumption of JCP increased serum glucose, insulin, triglycerides and cholesterol levels as well as the expression of transcription factors involved in lipogenesis and cholesterol synthesis (SREBP-1 and LXRα). Moreover, there was an increase in insulin signaling mediated by Akt phosphorylation and mTOR. JCP also increased PKCα protein abundance and the activation of downstream signaling pathway targets such as the AP1 and NF-κB transcription factors typically activated by phorbol esters. These results suggested that phorbol esters are present in JCP, and that they could be involved in the activation of PKC which may be responsible for the high insulin secretion and consequently the activation of insulin-dependent pathways. Our data suggest that this Mexican Jatropha variety contains toxic compounds that produce negative metabolic effects which require caution when using in the applications of Jatropha-based products in medicine and nutrition.

Tangshen formula attenuates hepatic steatosis by inhibiting hepatic lipogenesis and augmenting fatty acid oxidation in db/db mice.

Science.gov (United States)

Kong, Qin; Zhang, Haojun; Zhao, Tingting; Zhang, Weiku; Yan, Meihua; Dong, Xi; Li, Ping

2016-12-01

Tangshen formula (TSF), a well-prescribed traditional Chinese formula, has been used in the treatment of diabetic nephropathy. However, whether TSF ameliorates dyslipidemia and liver injury associated with diabetes remains unclear. In this study, we examined the effects of TSF on lipid profiles and hepatic steatosis in db/db mice. For this purpose, 8‑week-old db/db mice were treated with TSF or saline for 12 weeks via gavage and db/m mice were used as controls. Body weight and blood glucose levels were monitored weekly and bi-weekly, respectively. Blood samples were obtained for the analysis of lipids and enzymes related to hepatic function, and liver tissues were analyzed by histology, immunohistochemistry and molecular examination. The results revealed that TSF markedly reduced body weight, liver index [liver/body weight (LW/BW)] and improved lipid profiles, hepatic function and steatosis in db/db mice. TSF induced the phosphoralation of AMP-activated protein kinase and inhibited the activity of sterol regulatory element-binding protein 1 together with the inhibition of the expression of genes involved in de novo lipogenesis (DNL) and gluconeogenesis, such as fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), stearoyl CoA desaturase 1 (SCD1), glucose-6-phosphatase (G6pc) and phosphoenolpyruvate carboxykinase 1 (Pck1). Additionally, the silent mating type information regulation 2 homolog 1 (Sirt1)/peroxisome proliferator-activated receptor α (PPARα)/malonyl-CoA decarboxylase (MLYCD) cascade was potently activated by TSF in the liver and skeletal muscle of db/db mice, which led to enhanced fatty acid oxidation. These findings demonstrated that TSF attenuated hepatic fat accumulation and steatosis in db/db mice by inhibiting lipogenesis and augmenting fatty acid oxidation.

Power Control for D2D Underlay Cellular Networks with Imperfect CSI

KAUST Repository

Memmi, Amen

2017-02-09

Device-to-Device communications underlying the cellular infrastructure is a technology that has recently been proposed as a promising solution to enhance cellular network capabilities. However, interference is the major challenge since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this work, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Differently from previous works, we are assuming that the channel state information may be imperfect and include estimation errors. We evaluate how this uncertainty impacts performances. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name

Therapeutic intervention at cellular quality control systems in Alzheimer's and Parkinson's diseases.

Science.gov (United States)

Arduino, Daniela M; Esteves, A Raquel; Silva, Diana F F; Martins-Branco, Diogo; Santos, Daniel; Pimentel, Diana F Gomes; Cardoso, Sandra M

2011-01-01

Cellular homeostasis relies on quality control systems so that damaged biologic structures are either repaired or degraded and entirely replaced by newly formed proteins or even organelles. The clearance of dysfunctional cellular structures in long-lived postmitotic cells, like neurons, is essential to eliminate, per example, defective mitochondria, lipofuscin-loaded lysosomes and oxidized proteins. Short-lived proteins are degraded mainly by proteases and proteasomes whether most long-lived proteins and all organelles are digested by autophagy in the lysosomes. Recently, it an interplay was established between the ubiquitin-proteasome system and macroautophagy, so that both degradative mechanisms compensate for each other. In this article we describe each of these clearance systems and their contribution to neuronal quality control. We will highlight some of the findings that provide evidence for the dysfunction of these systems in Alzheimer's and Parkinson's diseases. Ultimately, we provide an outline on potential therapeutic interventions based on the modulation of cellular degradative systems.

Silibinin Capsules improves high fat diet-induced nonalcoholic fatty liver disease in hamsters through modifying hepatic de novo lipogenesis and fatty acid oxidation.

Science.gov (United States)

Cui, Chun-Xue; Deng, Jing-Na; Yan, Li; Liu, Yu-Ying; Fan, Jing-Yu; Mu, Hong-Na; Sun, Hao-Yu; Wang, Ying-Hong; Han, Jing-Yan

2017-08-17

Silibinin Capsules (SC) is a silybin-phospholipid complex with silybin as the bioactive component. Silybin accounts for 50-70% of the seed extract of Silybum marianum (L.) Gaertn.. As a traditional medicine, silybin has been used for treatment of liver diseases and is known to provide a wide range of hepatoprotective effects. High fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) is a worldwide health problem. This study was to investigate the role of SC in NAFLD with focusing on its underlying mechanism and likely target. Male hamsters (Cricetidae) received HFD for 10 weeks to establish NAFLD model. NAFLD was assessed by biochemical assays, histology and immunohistochemistry. Proton nuclear magnetic resonance spectroscopy and western blot were conducted to gain insight into the mechanism. Hamsters fed HFD for 10 weeks developed fatty liver accompanying with increased triglyceride (TG) accumulation, enhancing de novo lipogenesis, increase in fatty acid (FA) uptake and reducing FA oxidation and TG lipolysis, as well as a decrease in the expression of phospho-adenosine monophosphate activated protein kinase α (p-AMPKα) and Sirt 1. SC treatment at 50mg/kg silybin and 100mg/kg silybin for 8 weeks protected hamsters from development of fatty liver, reducing de novo lipogenesis and increasing FA oxidation and p-AMPKα expression, while having no effect on FA uptake and TG lipolysis. SC protected against NAFLD in hamsters by inhibition of de novo lipogenesis and promotion of FA oxidation, which was likely mediated by activation of AMPKα. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Malignant lipogenesis defined by {sup 11}C-acetate PET/CT predicts prostate cancer-specific survival in patients with biochemical relapse after prostatectomy

Energy Technology Data Exchange (ETDEWEB)

Regula, Naresh [Uppsala University, Section of Nuclear Medicine and PET, Department of Surgical Sciences, Uppsala (Sweden); Haeggman, Michael [Uppsala University, Section of Urology, Department of Surgical Sciences, Uppsala (Sweden); Johansson, Silvia [Uppsala University, Section of Oncology, Department of Immunology, Genetics and Pathology, Uppsala (Sweden); Soerensen, Jens [Uppsala University, Section of Nuclear Medicine and PET, Department of Surgical Sciences, Uppsala (Sweden); PET Center Research Department, Uppsala (Sweden)

2016-11-15

Malignant de novo lipogenesis is strongly linked to the aggressiveness of prostate cancer (PCa) under experimental conditions. {sup 11}C-Acetate PET/CT is a potential noninvasive biomarker of malignant lipogenesis in PCa, but its prognostic value is not known. The objective of this study was to analyse {sup 11}C-acetate PET/CT image metrics in relation to survival. All patients undergoing {sup 11}C-acetate PET/CT in one university hospital from 2005 to 2011 due to PSA relapse after previous prostatectomy were retrospectively evaluated. Two groups of patients were compared: those who died from PCa and those who were censored. All previously reported findings of local recurrence, regional or distal lymph node metastases and bone metastases were counted and evaluated regarding {sup 11}C-acetate uptake intensity (SUV{sub max}) and tumour volume. Total tumour volume and total lipogenic activity (TLA, summed SUV{sub max} x TV) were calculated. Survival analysis in the entire study population was followed by Cox proportional hazards ratio (HR) analysis. A total of 121 patients were included, and 22 PCa-specific deaths were recorded. The mean PSA level at the time of PET was 2.69 ± 4.35 ng/mL. The median follow-up of the study population was 79 ± 28 months. PET identified at least one PCa lesion in 53 % of patients. Five-year PCa-specific survival after PET was 80 % and 100 % in patients with a positive and a negative PET scan, respectively (p < 0.001). Time-to-death was linearly correlated with highest SUV{sub max} (r = -0.55, p = 0.01) and nonlinearly with TLA (r = -0.75, p < 0.001). Multivariate analysis showed statistical significance for number of bone metastases (HR 1.74, p = 0.01), tertile of TLA (HR 5.63, p = 0.029) and postoperative Gleason score (HR 1.84, p = 0.045). Malignant {sup 11}C-acetate accumulation measured with PET/CT is a strong predictor of survival in the setting of PSA relapse after prostatectomy. The study provides further evidence for a

CFTR depletion results in changes in fatty acid composition and promotes lipogenesis in intestinal Caco 2/15 cells.

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Geneviève Mailhot

2010-05-01

Full Text Available Abnormal fatty acid composition (FA in plasma and tissue lipids frequently occurs in homozygous and even in heterozygous carriers of cystic fibrosis transmembrane conductance regulator (CFTR mutations. The mechanism(s underlying these abnormalities remained, however, poorly understood despite the potentially CFTR contributing role.The aim of the present study was to investigate the impact of CFTR depletion on FA uptake, composition and metabolism using the intestinal Caco-2/15 cell line. shRNA-mediated cftr gene silencing induced qualitative and quantitative modifications in FA composition in differentiated enterocytes as determined by gas-liquid chromatography. With the cftr gene disruption, there was a 1,5 fold increase in the total FA amount, largely attributable to monounsaturated and saturated FA compared to controls. The activity of delta-7 desaturase, estimated by the 16:1(n-7/16:0, was significantly higher in knockdown cells and consistent with the striking elevation of the n-7 FA family. When incubated with [14C]-oleic acid, CFTR-depleted cells were capable of quick incorporation and export to the medium concomitantly with the high protein expression of L-FABP known to promote intracellular FA trafficking. Accordingly, lipoprotein vehicles (CM, VLDL, LDL and HDL, isolated from CFTR knockdown cells, exhibited higher levels of radiolabeled FA. Moreover, in the presence of [14C]-acetate, knockdown cells exhibited enhanced secretion of newly synthesized phospholipids, triglycerides, cholesteryl esters and free FA, thereby suggesting a stimulation of the lipogenic pathway. Conformably, gene expression of SREBP-1c, a key lipogenic transcription factor, was increased while protein expression of the phosphorylated and inactive form of acetylCoA carboxylase was reduced, confirming lipogenesis induction. Finally, CFTR-depleted cells exhibited lower gene expression of transcription factors (PPARalpha, LXRalpha, LXRbeta and RXRalpha

Service-Aware Retransmission Control in Cellular Networks

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Nadhir Ben Halima

2010-01-01

Full Text Available This paper proposes a service-aware cross-layer approach between application/transport layers on the mobile terminal and link layer on the wireless base station to enable dynamic control on the level of per-packet error protection for multimedia data streams. Specifically, in the context of cellular networks, the proposed scheme enables the mobile terminal to specify to the base station the desired level of Hybrid ARQ (HARQ protection by using an in-band control feedback channel. Such protection is dynamically adapted on a per-packet basis and depends on the perceptual importance of different packets as well as on the reception history of the flow. Experimental results demonstrate the potential benefits deriving from the proposed strategy either for audio and video real-time streams as well as for TCP-based data transfers.

Controlled cellular energy conversion in brown adipose tissue thermogenesis

Science.gov (United States)

Horowitz, J. M.; Plant, R. E.

1978-01-01

Brown adipose tissue serves as a model system for nonshivering thermogenesis (NST) since a) it has as a primary physiological function the conversion of chemical energy to heat; and b) preliminary data from other tissues involved in NST (e.g., muscle) indicate that parallel mechanisms may be involved. Now that biochemical pathways have been proposed for brown fat thermogenesis, cellular models consistent with a thermodynamic representation can be formulated. Stated concisely, the thermogenic mechanism in a brown fat cell can be considered as an energy converter involving a sequence of cellular events controlled by signals over the autonomic nervous system. A thermodynamic description for NST is developed in terms of a nonisothermal system under steady-state conditions using network thermodynamics. Pathways simulated include mitochondrial ATP synthesis, a Na+/K+ membrane pump, and ionic diffusion through the adipocyte membrane.

Long Noncoding RNA lncSHGL Recruits hnRNPA1 to Suppress Hepatic Gluconeogenesis and Lipogenesis.

Science.gov (United States)

Wang, Junpei; Yang, Weili; Chen, Zhenzhen; Chen, Ji; Meng, Yuhong; Feng, Biaoqi; Sun, Libo; Dou, Lin; Li, Jian; Cui, Qinghua; Yang, Jichun

2018-04-01

Mammalian genomes encode a huge number of long noncoding RNAs (lncRNAs) with unknown functions. This study determined the role and mechanism of a new lncRNA, lncRNA suppressor of hepatic gluconeogenesis and lipogenesis (lncSHGL), in regulating hepatic glucose/lipid metabolism. In the livers of obese mice and patients with nonalcoholic fatty liver disease, the expression levels of mouse lncSHGL and its human homologous lncRNA B4GALT1-AS1 were reduced. Hepatic lncSHGL restoration improved hyperglycemia, insulin resistance, and steatosis in obese diabetic mice, whereas hepatic lncSHGL inhibition promoted fasting hyperglycemia and lipid deposition in normal mice. lncSHGL overexpression increased Akt phosphorylation and repressed gluconeogenic and lipogenic gene expression in obese mouse livers, whereas lncSHGL inhibition exerted the opposite effects in normal mouse livers. Mechanistically, lncSHGL recruited heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) to enhance the translation efficiency of CALM mRNAs to increase calmodulin (CaM) protein level without affecting their transcription, leading to the activation of the phosphatidyl inositol 3-kinase (PI3K)/Akt pathway and repression of the mTOR/SREBP-1C pathway independent of insulin and calcium in hepatocytes. Hepatic hnRNPA1 overexpression also activated the CaM/Akt pathway and repressed the mTOR/SREBP-1C pathway to ameliorate hyperglycemia and steatosis in obese mice. In conclusion, lncSHGL is a novel insulin-independent suppressor of hepatic gluconeogenesis and lipogenesis. Activating the lncSHGL/hnRNPA1 axis represents a potential strategy for the treatment of type 2 diabetes and steatosis. © 2018 by the American Diabetes Association.

A Biologically-Inspired Power Control Algorithm for Energy-Efficient Cellular Networks

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Hyun-Ho Choi

2016-03-01

Full Text Available Most of the energy used to operate a cellular network is consumed by a base station (BS, and reducing the transmission power of a BS can therefore afford a substantial reduction in the amount of energy used in a network. In this paper, we propose a distributed transmit power control (TPC algorithm inspired by bird flocking behavior as a means of improving the energy efficiency of a cellular network. Just as each bird in a flock attempts to match its velocity with the average velocity of adjacent birds, in the proposed algorithm, each mobile station (MS in a cell matches its rate with the average rate of the co-channel MSs in adjacent cells by controlling the transmit power of its serving BS. We verify that this bio-inspired TPC algorithm using a local rate-average process achieves an exponential convergence and maximizes the minimum rate of the MSs concerned. Simulation results show that the proposed TPC algorithm follows the same convergence properties as the flocking algorithm and also effectively reduces the power consumption at the BSs while maintaining a low outage probability as the inter-cell interference increases; in so doing, it significantly improves the energy efficiency of a cellular network.

Femtosecond laser fabricated spike structures for selective control of cellular behavior.

Science.gov (United States)

Schlie, Sabrina; Fadeeva, Elena; Koch, Jürgen; Ngezahayo, Anaclet; Chichkov, Boris N

2010-09-01

In this study we investigate the potential of femtosecond laser generated micrometer sized spike structures as functional surfaces for selective cell controlling. The spike dimensions as well as the average spike to spike distance can be easily tuned by varying the process parameters. Moreover, negative replications in soft materials such as silicone elastomer can be produced. This allows tailoring of wetting properties of the spike structures and their negative replicas representing a reduced surface contact area. Furthermore, we investigated material effects on cellular behavior. By comparing human fibroblasts and SH-SY5Y neuroblastoma cells we found that the influence of the material was cell specific. The cells not only changed their morphology, but also the cell growth was affected. Whereas, neuroblastoma cells proliferated at the same rate on the spike structures as on the control surfaces, the proliferation of fibroblasts was reduced by the spike structures. These effects can result from the cell specific adhesion patterns as shown in this work. These findings show a possibility to design defined surface microstructures, which could control cellular behavior in a cell specific manner.

Energy-efficient power control for OFDMA cellular networks

KAUST Repository

Sboui, Lokman

2016-12-24

In this paper, we study the energy efficiency (EE) of orthogonal frequency-division multiple access (OFDMA) cellular networks. Our objective is to present a power allocation scheme that maximizes the EE of downlink communications. We propose a novel explicit expression of the optimal power allocation to each subcarrier. We also present the power control when the transmit power is limited by power budget constraint or/and minimal rate constraint and we highlight the occurrence of some transmission outage events depending on the constraints\\' parameters. In the numerical results, we show that our proposed power control improves the EE especially at high power budget regime and low minimal rate regime. In addition, we show that having a higher number of subcarriers enhances the OFDMA EE.

Salicylate activates AMPK and synergizes with metformin to reduce the survival of prostate and lung cancer cells ex vivo through inhibition of de novo lipogenesis.

Science.gov (United States)

O'Brien, Andrew J; Villani, Linda A; Broadfield, Lindsay A; Houde, Vanessa P; Galic, Sandra; Blandino, Giovanni; Kemp, Bruce E; Tsakiridis, Theodoros; Muti, Paola; Steinberg, Gregory R

2015-07-15

Aspirin, the pro-drug of salicylate, is associated with reduced incidence of death from cancers of the colon, lung and prostate and is commonly prescribed in combination with metformin in individuals with type 2 diabetes. Salicylate activates the AMP-activated protein kinase (AMPK) by binding at the A-769662 drug binding site on the AMPK β1-subunit, a mechanism that is distinct from metformin which disrupts the adenylate charge of the cell. A hallmark of many cancers is high rates of fatty acid synthesis and AMPK inhibits this pathway through phosphorylation of acetyl-CoA carboxylase (ACC). It is currently unknown whether targeting the AMPK-ACC-lipogenic pathway using salicylate and/or metformin may be effective for inhibiting cancer cell survival. Salicylate suppresses clonogenic survival of prostate and lung cancer cells at therapeutic concentrations achievable following the ingestion of aspirin (Salicylate concentrations of 1 mM increased the phosphorylation of ACC and suppressed de novo lipogenesis and these effects were enhanced with the addition of clinical concentrations of metformin (100 μM) and eliminated in mouse embryonic fibroblasts (MEFs) deficient in AMPK β1. Supplementation of media with fatty acids and/or cholesterol reverses the suppressive effects of salicylate and metformin on cell survival indicating the inhibition of de novo lipogenesis is probably important. Pre-clinical studies evaluating the use of salicylate based drugs alone and in combination with metformin to inhibit de novo lipogenesis and the survival of prostate and lung cancers are warranted. © 2015 Authors; published by Portland Press Limited.

Calorie Restricted High Protein Diets Downregulate Lipogenesis and Lower Intrahepatic Triglyceride Concentrations in Male Rats

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Lee M. Margolis

2016-09-01

Full Text Available The purpose of this investigation was to assess the influence of calorie restriction (CR alone, higher-protein/lower-carbohydrate intake alone, and combined CR higher-protein/lower-carbohydrate intake on glucose homeostasis, hepatic de novo lipogenesis (DNL, and intrahepatic triglycerides. Twelve-week old male Sprague Dawley rats consumed ad libitum (AL or CR (40% restriction, adequate (10%, or high (32% protein (PRO milk-based diets for 16 weeks. Metabolic profiles were assessed in serum, and intrahepatic triglyceride concentrations and molecular markers of de novo lipogenesis were determined in liver. Independent of calorie intake, 32% PRO tended to result in lower homeostatic model assessment of insulin resistance (HOMA-IR values compared to 10% PRO, while insulin and homeostatic model assessment of β-cell function (HOMA-β values were lower in CR than AL, regardless of protein intake. Intrahepatic triglyceride concentrations were 27.4 ± 4.5 and 11.7 ± 4.5 µmol·g−1 lower (p < 0.05 in CR and 32% PRO compared to AL and 10% PRO, respectively. Gene expression of fatty acid synthase (FASN, stearoyl-CoA destaurase-1 (SCD1 and pyruvate dehydrogenase kinase, isozyme 4 (PDK4 were 45% ± 1%, 23% ± 1%, and 57% ± 1% lower (p < 0.05, respectively, in CR than AL, regardless of protein intake. Total protein of FASN and SCD were 50% ± 1% and 26% ± 1% lower (p < 0.05 in 32% PRO compared to 10% PRO, independent of calorie intake. Results from this investigation provide evidence that the metabolic health benefits associated with CR—specifically reduction in intrahepatic triglyceride content—may be enhanced by consuming a higher-protein/lower-carbohydrate diet.

A cellular automata approach to chemical reactions : 1 reaction controlled systems

NARCIS (Netherlands)

Korte, de A.C.J.; Brouwers, H.J.H.

2013-01-01

A direct link between the chemical reaction controlled (shrinking core) model and cellular automata, to study the dissolution of particles, is derived in this paper. Previous research on first and second order reactions is based on the concentration of the reactant. The present paper describes the

Hepatic Steatosis is Common in Adolescents with Obesity and PCOS and Relates to De Novo Lipogenesis but Insulin Resistance

Science.gov (United States)

Cree-Green, M.; Bergman, B. C.; Coe, G. V.; Newnes, L.; Baumgartner, A.D.; Bacon, S.; Sherzinger, A.; Pyle, L.; Nadeau, K. J.

2016-01-01

Objective Increased liver fat and type 2 diabetes are prevalent in women with polycystic ovarian syndrome (PCOS) and cause excess mortality, yet little is known about their development during adolescence. Our goal was to measure hepatic steatosis and related metabolic contributors in girls with obesity, with and without PCOS. Methods Nondiabetic adolescents with obesity, 41 with PCOS (PCOS; age 15.0(13.0,16.0) years, BMI 35.2±0.61 kg/m2) and 30 without PCOS (OB; age 14.5(13.0,17.0), BMI 33.2±1.8) were studied. Visceral and liver fat were assessed with MRI. Serum measures included androgens and 16 and 18 n7 fatty acids specific to de novo lipogenesis. Adipose, hepatic and peripheral insulin sensitivity (IS) were assessed with a 4-phase hyperinsulinemic-euglycemic clamp with isotope tracers. Results 49% PCOS had hepatic steatosis vs. 14% OB (p=0.02), and PCOS had higher n7 (43±4 nmol/g vs. 29±5; p=0.02). Peripheral IS was lower in PCOS (9.4(7.2,12.3) mg/lean kg/min vs. 14.5(13.1,18.05); pandrogens or peripheral IS. Conclusions Nearly 50% of nondiabetic girls with PCOS and obesity have hepatic steatosis, which related to visceral fat and lipogenesis, but not to IS or androgens. PMID:27804265

Lipogenesis and glucose production in dwarf carrier and normal lines of chicks

International Nuclear Information System (INIS)

Rosebrough, R.W.; McMurtry, J.P.; Steele, N.C.

1986-01-01

Diets containing 13, 16, 19, or 23% protein and 70% carbohydrate calories were fed to dwarf heterozygote (dw) and normal (Dw) chickens to determine the effects of age (weeks) and protein on intermediary metabolism. In vitro lipogenesis (IVL) was determined by the incorporation of acetate (10 and 20 mM 2 14 C-Acet/2hr) into hepatic fatty acids. Net glucose production (NGP) was determined as the difference in media glucose in the presence or absence of 10 mM pyruvate. Values were expressed per unit of relative liver size (μmoles/100 g BWt). Serum insulin (INS; ng/ml) was determined by homologous radioimmunoassay. Results indicate that although INS was greater in Dw than in dw, this difference was not reflected in a decreased rate of glucose production to accompany the difference in IVL between the two lines. Moreover, an increase in dietary protein resulted in a decrease in IVL but an increase in INS

Cellular Controlled Short-Range Communication for Cooperative P2P Networking

DEFF Research Database (Denmark)

Fitzek, Frank H. P.; Katz, Marcos; Zhang, Qi

2009-01-01

-range communication network among cooperating mobile and wireless devices. The role of the mobile device will change, from being an agnostic entity in respect to the surrounding world to a cognitive device. This cognitive device is capable of being aware of the neighboring devices as well as on the possibility......This article advocates a novel communication architecture and associated collaborative framework for future wireless communication systems. In contrast to the dominating cellular architecture and the upcoming peer-to-peer architecture, the new approach envisions a cellular controlled short...... to establish cooperation with them. The novel architecture together with several possible cooperative strategies will bring clear benefits for the network and service providers, mobile device manufacturers and also end users....

The adaptive cruise control vehicles in the cellular automata model

International Nuclear Information System (INIS)

Jiang Rui; Wu Qingsong

2006-01-01

This Letter presented a cellular automata model where the adaptive cruise control vehicles are modelled. In this model, the constant time headway policy is adopted. The fundamental diagram is presented. The simulation results are in good agreement with the analytical ones. The mixture of ACC vehicles with manually driven vehicles is investigated. It is shown that with the introduction of ACC vehicles, the jam can be suppressed

Physical Property Control on the Cellular Uptake Pathway and Spatial Distribution of Nanoparticles in Cells.

Science.gov (United States)

Ahn, Sungsook; Seo, Eunseok; Kim, Ki Hean; Lee, Sang Joon

2015-06-01

Nanoparticles have been developed in broad biomedical research in terms of effective cellular interactions to treat and visualize diseased cells. Considering the charge and polar functional groups of proteins that are embedded in cellular membranes, charged nanoparticles have been strategically developed to enhance electrostatic cellular interactions. In this study, we show that cellular uptake efficiency, pathway, and spatial distribution of gold nanoparticles in a cell are significantly modulated based on the surface condition of gold nanoparticles and human cancer cells that were tuned by controlling the pH of the medium and by introducing an electron beam. Cellular uptake efficiency is increased when electrostatic attraction is induced between the cells and the gold nanoparticles. Cell surface modification changes the cellular uptake pathways of the gold nanoparticles and concentrates the gold nanoparticles at the membrane region. Surface modification of the gold nanoparticles also contributes to deep penetration and homogeneous spatial distributions in a cell.

Chronic innate immune activation of TBK1 suppresses mTORC1 activity and dysregulates cellular metabolism.

Science.gov (United States)

Hasan, Maroof; Gonugunta, Vijay K; Dobbs, Nicole; Ali, Aktar; Palchik, Guillermo; Calvaruso, Maria A; DeBerardinis, Ralph J; Yan, Nan

2017-01-24

Three-prime repair exonuclease 1 knockout (Trex1 -/- ) mice suffer from systemic inflammation caused largely by chronic activation of the cyclic GMP-AMP synthase-stimulator of interferon genes-TANK-binding kinase-interferon regulatory factor 3 (cGAS-STING-TBK1-IRF3) signaling pathway. We showed previously that Trex1-deficient cells have reduced mammalian target of rapamycin complex 1 (mTORC1) activity, although the underlying mechanism is unclear. Here, we performed detailed metabolic analysis in Trex1 -/- mice and cells that revealed both cellular and systemic metabolic defects, including reduced mitochondrial respiration and increased glycolysis, energy expenditure, and fat metabolism. We also genetically separated the inflammatory and metabolic phenotypes by showing that Sting deficiency rescued both inflammatory and metabolic phenotypes, whereas Irf3 deficiency only rescued inflammation on the Trex1 -/- background, and many metabolic defects persist in Trex1 -/- Irf3 -/- cells and mice. We also showed that Leptin deficiency (ob/ob) increased lipogenesis and prolonged survival of Trex1 -/- mice without dampening inflammation. Mechanistically, we identified TBK1 as a key regulator of mTORC1 activity in Trex1 -/- cells. Together, our data demonstrate that chronic innate immune activation of TBK1 suppresses mTORC1 activity, leading to dysregulated cellular metabolism.

Cellular oxido-reductive proteins of Chlamydomonas reinhardtii control the biosynthesis of silver nanoparticles

Directory of Open Access Journals (Sweden)

Barwal Indu

2011-12-01

Full Text Available Abstract Background Elucidation of molecular mechanism of silver nanoparticles (SNPs biosynthesis is important to control its size, shape and monodispersity. The evaluation of molecular mechanism of biosynthesis of SNPs is of prime importance for the commercialization and methodology development for controlling the shape and size (uniform distribution of SNPs. The unicellular algae Chlamydomonas reinhardtii was exploited as a model system to elucidate the role of cellular proteins in SNPs biosynthesis. Results The C. reinhardtii cell free extract (in vitro and in vivo cells mediated synthesis of silver nanoparticles reveals SNPs of size range 5 ± 1 to 15 ± 2 nm and 5 ± 1 to 35 ± 5 nm respectively. In vivo biosynthesized SNPs were localized in the peripheral cytoplasm and at one side of flagella root, the site of pathway of ATP transport and its synthesis related enzymes. This provides an evidence for the involvement of oxidoreductive proteins in biosynthesis and stabilization of SNPs. Alteration in size distribution and decrease of synthesis rate of SNPs in protein-depleted fractions confirmed the involvement of cellular proteins in SNPs biosynthesis. Spectroscopic and SDS-PAGE analysis indicate the association of various proteins on C. reinhardtii mediated in vivo and in vitro biosynthesized SNPs. We have identified various cellular proteins associated with biosynthesized (in vivo and in vitro SNPs by using MALDI-MS-MS, like ATP synthase, superoxide dismutase, carbonic anhydrase, ferredoxin-NADP+ reductase, histone etc. However, these proteins were not associated on the incubation of pre-synthesized silver nanoparticles in vitro. Conclusion Present study provides the indication of involvement of molecular machinery and various cellular proteins in the biosynthesis of silver nanoparticles. In this report, the study is mainly focused towards understanding the role of diverse cellular protein in the synthesis and capping of silver

Structure and Electromagnetic Properties of Cellular Glassy Carbon Monoliths with Controlled Cell Size

Directory of Open Access Journals (Sweden)

Andrzej Szczurek

2018-05-01

Full Text Available Electromagnetic shielding is a topic of high importance for which lightweight materials are highly sought. Porous carbon materials can meet this goal, but their structure needs to be controlled as much as possible. In this work, cellular carbon monoliths of well-defined porosity and cell size were prepared by a template method, using sacrificial paraffin spheres as the porogen and resorcinol-formaldehyde (RF resin as the carbon precursor. Physicochemical studies were carried out for investigating the conversion of RF resin into carbon, and the final cellular monoliths were investigated in terms of elemental composition, total porosity, surface area, micropore volumes, and micro/macropore size distributions. Electrical and electromagnetic (EM properties were investigated in the static regime and in the Ka-band, respectively. Due to the phenolic nature of the resin, the resultant carbon was glasslike, and the special preparation protocol that was used led to cellular materials whose cell size increased with density. The materials were shown to be relevant for EM shielding, and the relationships between those properties and the density/cell size of those cellular monoliths were elucidated.

Linear matrix inequality approach for synchronization control of fuzzy cellular neural networks with mixed time delays

International Nuclear Information System (INIS)

Balasubramaniam, P.; Kalpana, M.; Rakkiyappan, R.

2012-01-01

Fuzzy cellular neural networks (FCNNs) are special kinds of cellular neural networks (CNNs). Each cell in an FCNN contains fuzzy operating abilities. The entire network is governed by cellular computing laws. The design of FCNNs is based on fuzzy local rules. In this paper, a linear matrix inequality (LMI) approach for synchronization control of FCNNs with mixed delays is investigated. Mixed delays include discrete time-varying delays and unbounded distributed delays. A dynamic control scheme is proposed to achieve the synchronization between a drive network and a response network. By constructing the Lyapunov—Krasovskii functional which contains a triple-integral term and the free-weighting matrices method an improved delay-dependent stability criterion is derived in terms of LMIs. The controller can be easily obtained by solving the derived LMIs. A numerical example and its simulations are presented to illustrate the effectiveness of the proposed method. (interdisciplinary physics and related areas of science and technology)

Flexible control of cellular encapsulation, permeability, and release in a droplet-templated bifunctional copolymer scaffold.

Science.gov (United States)

Chen, Qiushui; Chen, Dong; Wu, Jing; Lin, Jin-Ming

2016-11-01

Designing cell-compatible, bio-degradable, and stimuli-responsive hydrogels is very important for biomedical applications in cellular delivery and micro-scale tissue engineering. Here, we report achieving flexible control of cellular microencapsulation, permeability, and release by rationally designing a diblock copolymer, alginate-conjugated poly(N-isopropylacrylamide) (Alg-co-PNiPAM). We use the microfluidic technique to fabricate the bifunctional copolymers into thousands of mono-disperse droplet-templated hydrogel microparticles for controlled encapsulation and triggered release of mammalian cells. In particular, the grafting PNiPAM groups in the synthetic cell-laden microgels produce lots of nano-aggregates into hydrogel networks at elevated temperature, thereafter enhancing the permeability of microparticle scaffolds. Importantly, the hydrogel scaffolds are readily fabricated via on-chip quick gelation by triggered release of Ca 2+ from the Ca-EDTA complex; it is also quite exciting that very mild release of microencapsulated cells is achieved via controlled degradation of hydrogel scaffolds through a simple strategy of competitive affinity of Ca 2+ from the Ca-Alginate complex. This finding suggests that we are able to control cellular encapsulation and release through ion-induced gelation and degradation of the hydrogel scaffolds. Subsequently, we demonstrate a high viability of microencapsulated cells in the microgel scaffolds.

Design of a bistable switch to control cellular uptake.

Science.gov (United States)

Oyarzún, Diego A; Chaves, Madalena

2015-12-06

Bistable switches are widely used in synthetic biology to trigger cellular functions in response to environmental signals. All bistable switches developed so far, however, control the expression of target genes without access to other layers of the cellular machinery. Here, we propose a bistable switch to control the rate at which cells take up a metabolite from the environment. An uptake switch provides a new interface to command metabolic activity from the extracellular space and has great potential as a building block in more complex circuits that coordinate pathway activity across cell cultures, allocate metabolic tasks among different strains or require cell-to-cell communication with metabolic signals. Inspired by uptake systems found in nature, we propose to couple metabolite import and utilization with a genetic circuit under feedback regulation. Using mathematical models and analysis, we determined the circuit architectures that produce bistability and obtained their design space for bistability in terms of experimentally tuneable parameters. We found an activation-repression architecture to be the most robust switch because it displays bistability for the largest range of design parameters and requires little fine-tuning of the promoters' response curves. Our analytic results are based on on-off approximations of promoter activity and are in excellent qualitative agreement with simulations of more realistic models. With further analysis and simulation, we established conditions to maximize the parameter design space and to produce bimodal phenotypes via hysteresis and cell-to-cell variability. Our results highlight how mathematical analysis can drive the discovery of new circuits for synthetic biology, as the proposed circuit has all the hallmarks of a toggle switch and stands as a promising design to control metabolic phenotypes across cell cultures. © 2015 The Author(s).

Power Control for D2D Underlay Cellular Networks With Channel Uncertainty

KAUST Repository

Memmi, Amen

2016-12-26

Device-to-device (D2D) communications underlying the cellular infrastructure are a technology that have been proposed recently as a promising solution to enhance cellular network capabilities. It improves spectrum utilization, overall throughput, and energy efficiency while enabling new peer-to-peer and location-based applications and services. However, interference is the major challenge, since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this paper, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Existing results on D2D underlay networks assume perfect channel state information (CSI). This assumption is usually unrealistic in practice due to the dynamic nature of wireless channels. Thus, it is of great interest to study and evaluate achievable performances under channel uncertainty. Differently from previous works, we are assuming that the CSI may be imperfect and include estimation errors. In the centralized approach, we derive the optimal powers that maximize the coverage probability and the rate of the cellular user while scheduling as many D2D links as possible. These powers are computed at the base station (BS) and then delivered to the users, and hence the name “centralized”. For the distributed method, the ON–OFF power control and the truncated channel inversion are proposed. Expressions of coverage probabilities are established in the function of D2D links intensity, pathloss exponent, and estimation error variance. Results show the important influence of CSI error on achievable performances and thus how crucial it is to consider it while designing networks and evaluating performances.

Programmable cellular arrays. Faults testing and correcting in cellular arrays

International Nuclear Information System (INIS)

Cercel, L.

1978-03-01

A review of some recent researches about programmable cellular arrays in computing and digital processing of information systems is presented, and includes both combinational and sequential arrays, with full arbitrary behaviour, or which can realize better implementations of specialized blocks as: arithmetic units, counters, comparators, control systems, memory blocks, etc. Also, the paper presents applications of cellular arrays in microprogramming, in implementing of a specialized computer for matrix operations, in modeling of universal computing systems. The last section deals with problems of fault testing and correcting in cellular arrays. (author)

Analytical modeling of mode selection and power control for underlay D2D communication in cellular networks

KAUST Repository

Elsawy, Hesham

2014-11-01

Device-to-device (D2D) communication enables the user equipments (UEs) located in close proximity to bypass the cellular base stations (BSs) and directly connect to each other, and thereby, offload traffic from the cellular infrastructure. D2D communication can improve spatial frequency reuse and energy efficiency in cellular networks. This paper presents a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with a flexible mode selection scheme along with truncated channel inversion power control. The developed framework is used to analyze and understand how the underlaying D2D communication affects the cellular network performance. Through comprehensive numerical analysis, we investigate the expected performance gains and provide guidelines for selecting the network parameters.

A celiac cellular phenotype, with altered LPP sub-cellular distribution, is inducible in controls by the toxic gliadin peptide P31-43.

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Merlin Nanayakkara

Full Text Available Celiac disease (CD is a frequent inflammatory intestinal disease, with a genetic background, caused by gliadin-containing food. Undigested gliadin peptides P31-43 and P57-68 induce innate and adaptive T cell-mediated immune responses, respectively. Alterations in the cell shape and actin cytoskeleton are present in celiac enterocytes, and gliadin peptides induce actin rearrangements in both the CD mucosa and cell lines. Cell shape is maintained by the actin cytoskeleton and focal adhesions, sites of membrane attachment to the extracellular matrix. The locus of the human Lipoma Preferred Partner (LPP gene was identified as strongly associated with CD using genome-wide association studies (GWAS. The LPP protein plays an important role in focal adhesion architecture and acts as a transcription factor in the nucleus. In this study, we examined the hypothesis that a constitutive alteration of the cell shape and the cytoskeleton, involving LPP, occurs in a cell compartment far from the main inflammation site in CD fibroblasts from skin explants. We analyzed the cell shape, actin organization, focal adhesion number, focal adhesion proteins, LPP sub-cellular distribution and adhesion to fibronectin of fibroblasts obtained from CD patients on a Gluten-Free Diet (GFD and controls, without and with treatment with A-gliadin peptide P31-43. We observed a "CD cellular phenotype" in these fibroblasts, characterized by an altered cell shape and actin organization, increased number of focal adhesions, and altered intracellular LPP protein distribution. The treatment of controls fibroblasts with gliadin peptide P31-43 mimics the CD cellular phenotype regarding the cell shape, adhesion capacity, focal adhesion number and LPP sub-cellular distribution, suggesting a close association between these alterations and CD pathogenesis.

Efficacy of Cellular Therapy for Diabetic Foot Ulcer: A Meta-Analysis of Randomized Controlled Clinical Trials.

Science.gov (United States)

Zhang, Ye; Deng, Hong; Tang, Zhouping

2017-12-01

Diabetes mellitus is a widely spread chronic disease with growing incidence worldwide, and diabetic foot ulcer is one of the most serious complications of diabetes. Cellular therapy has shown promise in the management of diabetic foot ulcer in many preclinical experiments and clinical researches. Here, we performed a meta-analysis to evaluate the efficacy and safety of cellular therapy in the management of diabetic foot ulcer. We systematically searched PubMed, MEDLINE, EMBASE, and Cochrane Library databases from inception to May 2017 for randomized controlled trials assessing the efficacy of cellular therapy in diabetic foot ulcer, and a meta-analysis was conducted. A total of 6 randomized controlled clinical trials involving 241 individuals were included in this meta-analysis. The results suggested that cellular therapy could help accelerating the healing of diabetic foot ulcer, presented as higher ankle-brachial index (mean difference = 0.17, 95% confidence interval [CI] = 0.11 to 0.23), higher transcutaneous oxygen pressure (standardized mean difference [SMD] = 1.43; 95% CI, 1.09- to 1.78), higher ulcer healing rate (relative risk [RR] = 1.78; 95% CI, 1.41 to 2.25), higher amputation-free survival (RR = 1.25; 95% CI, 1.11 to 1.40), and lower scale of pain (SMD = -1.69; 95% CI, -2.05 to -1.33). Furthermore, cellular therapy seemed to be safe, with no serious complications and low risk of short-term slight complications. Cellular therapy could accelerate the rate of diabetic foot ulcer healing and may be more efficient than standard therapy for diabetic foot treatment.

Role of cellular oxalate in oxalate clearance of patients with calcium oxalate monohydrate stone formation and normal controls.

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Oehlschläger, Sven; Fuessel, Susanne; Meye, Axel; Herrmann, Jana; Froehner, Michael; Albrecht, Steffen; Wirth, Manfred P

2009-03-01

To examine the cellular, plasma, and urinary oxalate and erythrocyte oxalate flux in patients with calcium oxalate monohydrate (COM) stone formation vs normal controls. Pathologic oxalate clearance in humans is mostly integrated in calcium oxalate stone formation. An underlying cause of deficient oxalate clearance could be defective transmembrane oxalate transport, which, in many tissues, is regulated by an anion exchanger (SLC26). We studied 2 groups: 40 normal controls and 41 patients with COM stone formation. Red blood cells were divided for cellular oxalate measurement and for resuspension in a buffered solution (pH 7.40); 0.1 mmol/L oxalate was added. The supernatant was measured for oxalate immediately and 1 hour after incubation. The plasma and urinary oxalate were analyzed in parallel. The mean cellular oxalate concentrations were significantly greater in the normal controls (5.25 +/- 0.47 micromol/L) than in those with COM stone formation (2.36 +/- 0.28 micromol/L; P stone formation (0.31 +/- 0.02 mmol/L) than in the controls (0.24 +/- 0.02 mmol/L; P r = 0.49-0.63; P r = -0.29-0.41; P r = -0.30; P r = 0.25; P stone formation. Our data implicate the presence of a cellular oxalate buffer to stabilize plasma and urinary oxalate concentrations in normal controls.

Reductive glutamine metabolism by IDH1 mediates lipogenesis under hypoxia

Science.gov (United States)

Metallo, Christian M.; Gameiro, Paulo A.; Bell, Eric L.; Mattaini, Katherine R.; Yang, Juanjuan; Hiller, Karsten; Jewell, Christopher M.; Johnson, Zachary R.; Irvine, Darrell J.; Guarente, Leonard; Kelleher, Joanne K.; Vander Heiden, Matthew G.; Iliopoulos, Othon; Stephanopoulos, Gregory

2013-01-01

Acetyl coenzyme A (AcCoA) is the central biosynthetic precursor for fatty acid synthesis and protein acetylation. In the conventional view of mammalian cell metabolism, AcCoA is primarily generated from glucose-derived pyruvate through the citrate shuttle and adenosine triphosphate citrate lyase (ACL) in the cytosol1-3. However, proliferating cells that exhibit aerobic glycolysis and those exposed to hypoxia convert glucose to lactate at near stoichiometric levels, directing glucose carbon away from the tricarboxylic acid cycle (TCA) and fatty acid synthesis4. Although glutamine is consumed at levels exceeding that required for nitrogen biosynthesis5, the regulation and utilization of glutamine metabolism in hypoxic cells is not well understood. Here we show that human cells employ reductive metabolism of alpha-ketoglutarate (αKG) to synthesize AcCoA for lipid synthesis. This isocitrate dehydrogenase 1 (IDH1) dependent pathway is active in most cell lines under normal culture conditions, but cells grown under hypoxia rely almost exclusively on the reductive carboxylation of glutamine-derived αKG for de novo lipogenesis. Furthermore, renal cell lines deficient in the von Hippel-Lindau (VHL) tumor suppressor protein preferentially utilize reductive glutamine metabolism for lipid biosynthesis even at normal oxygen levels. These results identify a critical role for oxygen in regulating carbon utilization in order to produce AcCoA and support lipid synthesis in mammalian cells. PMID:22101433

Pre-analytical and post-analytical evaluation in the era of molecular diagnosis of sexually transmitted diseases: cellularity control and internal control

Directory of Open Access Journals (Sweden)

Loria Bianchi

2014-06-01

Full Text Available Background. Increase of molecular tests performed on DNA extracted from various biological materials should not be carried out without an adequate standardization of the pre-analytical and post-analytical phase. Materials and Methods. Aim of this study was to evaluate the role of internal control (IC to standardize pre-analytical phase and the role of cellularity control (CC in the suitability evaluation of biological matrices, and their influence on false negative results. 120 cervical swabs (CS were pre-treated and extracted following 3 different protocols. Extraction performance was evaluated by amplification of: IC, added in each mix extraction; human gene HPRT1 (CC with RT-PCR to quantify sample cellularity; L1 region of HPV with SPF10 primers. 135 urine, 135 urethral swabs, 553 CS and 332 ThinPrep swabs (TP were tested for C. trachomatis (CT and U. parvum (UP with RT-PCR and for HPV by endpoint-PCR. Samples were also tested for cellularity. Results. Extraction protocol with highest average cellularity (Ac/sample showed lowest number of samples with inhibitors; highest HPV positivity was achieved by protocol with greatest Ac/PCR. CS and TP under 300.000 cells/sample showed a significant decrease of UP (P<0.01 and HPV (P<0.005 positivity. Female urine under 40.000 cells/mL were inadequate to detect UP (P<0.05. Conclusions. Our data show that IC and CC allow optimization of pre-analytical phase, with an increase of analytical quality. Cellularity/sample allows better sample adequacy evaluation, crucial to avoid false negative results, while cellularity/PCR allows better optimization of PCR amplification. Further data are required to define the optimal cut-off for result normalization.

On stochastic geometry modeling of cellular uplink transmission with truncated channel inversion power control

KAUST Repository

Elsawy, Hesham; Hossain, Ekram

2014-01-01

Using stochastic geometry, we develop a tractable uplink modeling paradigm for outage probability and spectral efficiency in both single and multi-tier cellular wireless networks. The analysis accounts for per user equipment (UE) power control

On mode selection and power control for uplink D2D communication in cellular networks

KAUST Repository

Ali, Konpal S.

2015-06-08

Device-to-device (D2D) communication enables users lying in close proximity to bypass the cellular base station (BS) and transmit to one another directly. This offloads traffic from the cellular network, improves spatial frequency reuse and energy efficiency in the network. We present a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with two different flexible mode-selection schemes. The power-control cutoff thresholds of the two communication modes have been decoupled unlike past work on the subject. We find that for a given network, an optimal value exists not only for the biased mode selection criterion, but also for r, the ratio of the power-control cutoff thresholds of the two communication modes, which maximizes spatial spectral efficiency. Also, r turns out to be a more robust parameter for optimizing network performance. Further, it is shown that the second scheme, which prioritizes spatial frequency reuse over the per-user achievable performance compared to the first scheme, achieves almost the same overall network performance; thereby trading per user performance to serve a larger number of users.

On mode selection and power control for uplink D2D communication in cellular networks

KAUST Repository

Ali, Konpal S.; Elsawy, Hesham; Alouini, Mohamed-Slim

2015-01-01

Device-to-device (D2D) communication enables users lying in close proximity to bypass the cellular base station (BS) and transmit to one another directly. This offloads traffic from the cellular network, improves spatial frequency reuse and energy efficiency in the network. We present a comprehensive and tractable analytical framework for D2D-enabled uplink cellular networks with two different flexible mode-selection schemes. The power-control cutoff thresholds of the two communication modes have been decoupled unlike past work on the subject. We find that for a given network, an optimal value exists not only for the biased mode selection criterion, but also for r, the ratio of the power-control cutoff thresholds of the two communication modes, which maximizes spatial spectral efficiency. Also, r turns out to be a more robust parameter for optimizing network performance. Further, it is shown that the second scheme, which prioritizes spatial frequency reuse over the per-user achievable performance compared to the first scheme, achieves almost the same overall network performance; thereby trading per user performance to serve a larger number of users.

A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system

Institute of Scientific and Technical Information of China (English)

无

2005-01-01

Joint power control has advantages of multi-user detection and power control; and it can combat the multi-access interference and the near-far problem. A novel adaptive joint power control algorithm with channel estimation in a CDMA cellular system was designed. Simulation results show that the algorithm can control the power not only quickly but also precisely with a time change. The method is useful for increasing system capacity.

Hepatic Steatosis is Common in Adolescents with Obesity and PCOS and Relates to De Novo Lipogenesis but not Insulin Resistance.

Science.gov (United States)

Cree-Green, Melanie; Bergman, Bryan C; Coe, Gregory V; Newnes, Lindsey; Baumgartner, Amy D; Bacon, Samantha; Sherzinger, Ann; Pyle, Laura; Nadeau, Kristen J

2016-11-01

Increased liver fat and type 2 diabetes are prevalent in women with polycystic ovarian syndrome (PCOS) and cause excess mortality, yet little is known about their development during adolescence. The objective of this study was to measure hepatic steatosis and related metabolic contributors in girls with obesity, with and without PCOS. Nondiabetic adolescents with obesity, 41 with PCOS (PCOS; age 15.0 [13.0-16.0] years, BMI 35.2 ± 0.61 kg/m 2 ) and 30 without PCOS (OB; age 14.5 [13.0-17.0], BMI 33.2 ± 1.8), were studied. Visceral and liver fat were assessed with MRI. Serum measures included androgens and 16:1 and 18:1 N7 fatty acids specific to de novo lipogenesis. Adipose, hepatic, and peripheral insulin sensitivity (IS) were assessed with a four-phase hyperinsulinemic-euglycemic clamp with isotope tracers. Forty-nine percent of the PCOS group had hepatic steatosis versus fourteen percent of the OB group (P = 0.02), and the PCOS group had higher N7 (43 ± 4 vs. 29 ± 5 nmol/g; P = 0.02). Peripheral IS was lower in PCOS (9.4 [7.2-12.3] vs. 14.5 [13.1-18.05 mg/lean kg/min]; P androgens or peripheral IS. Nearly 50% of nondiabetic girls with PCOS and obesity have hepatic steatosis, which relates to visceral fat and lipogenesis, but not to IS or androgens. © 2016 The Obesity Society.

BDE-47 induces oxidative stress, activates MAPK signaling pathway, and elevates de novo lipogenesis in the copepod Paracyclopina nana.

Science.gov (United States)

Lee, Min-Chul; Puthumana, Jayesh; Lee, Seung-Hwi; Kang, Hye-Min; Park, Jun Chul; Jeong, Chang-Bum; Han, Jeonghoon; Hwang, Dae-Sik; Seo, Jung Soo; Park, Heum Gi; Om, Ae-Son; Lee, Jae-Seong

2016-12-01

Brominated flame retardant, 2, 2', 4, 4'-tetrabromodiphenyl ether (BDE-47), has received grave concerns as a persistent organic pollutant, which is toxic to marine organisms, and a suspected link to endocrine abnormalities. Despite the wide distribution in the marine ecosystem, very little is known about the toxic impairments on marine organisms, particularly on invertebrates. Thus, we examined the adverse effects of BDE-47 on life history trait (development), oxidative markers, fatty acid composition, and lipid accumulation in response to BDE-47-induced stress in the marine copepod Paracyclopina nana. Also, activation level of mitogen-activated protein kinase (MAPK) signaling pathways along with the gene expression profile of de novo lipogenesis (DNL) pathways were addressed. As a result, BDE-47 induced oxidative stress (e.g. reactive oxygen species, ROS) mediated activation of extracellular signal-regulated kinase (ERK) and c-Jun-N-terminal kinase (JNK) signaling cascades in MAPK pathways. Activated MAPK pathways, in turn, induced signal molecules that bind to the transcription factors (TFs) responsible for lipogenesis to EcR, SREBP, ChREBP promoters. Also, the stress stimulated the conversion of saturated fatty acids (SFAs) to polyunsaturated fatty acids (PUFAs), a preparedness of the organism to adapt the observed stress, which could be correlated with the elongase and desaturase gene (e.g. ELO3, Δ5-DES, Δ9-DES) expressions, and then extended to the delayed early post-embryonic development and increased accumulation of lipid droplets in P. nana. This study will provide a better understanding of how BDE-47 effects on marine invertebrates particularly on the copepods, an important link in the marine food chain. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of dietary nutrient composition on de novo lipogenesis in gilthead sea bream (Sparus aurata)

DEFF Research Database (Denmark)

Ekmann, Kim Schøn

rate of 18.7 to 123.7 mg/kg biomass/day, when feeding iso-DP and iso-DE diets ranging between 6 and 24% dietary starch, respectively. Additionally, up to 68.8% of the hepatic glycogen pool could be attributed to dietary starch, while the same was true for up to 38.8% of the whole body glycogen pool...... (using diets otherwise iso-DP and iso-DE). The apparent retention of saturated fatty acids (SAFA) and mono unsaturated fatty acids (MUFA) were positively related to dietary starch level (and negatively related to dietary lipid level), exceeding 100% in fish fed high starch diets. These findings...... and the PUFA content to decrease when increasing dietary starch level, adversely affecting the overall FA quality of the final product. Considering lipogenesis results, nutrient retention efficiencies and body composition results obtained in the three trials collectively, gilthead sea bream appear to endeavour...

Amino acids and autophagy: cross-talk and co-operation to control cellular homeostasis.

Science.gov (United States)

Carroll, Bernadette; Korolchuk, Viktor I; Sarkar, Sovan

2015-10-01

Maintenance of amino acid homeostasis is important for healthy cellular function, metabolism and growth. Intracellular amino acid concentrations are dynamic; the high demand for protein synthesis must be met with constant dietary intake, followed by cellular influx, utilization and recycling of nutrients. Autophagy is a catabolic process via which superfluous or damaged proteins and organelles are delivered to the lysosome and degraded to release free amino acids into the cytoplasm. Furthermore, autophagy is specifically activated in response to amino acid starvation via two key signaling cascades: the mammalian target of rapamycin (mTOR) complex 1 (mTORC1) and the general control nonderepressible 2 (GCN2) pathways. These pathways are key regulators of the integration between anabolic (amino acid depleting) and catabolic (such as autophagy which is amino acid replenishing) processes to ensure intracellular amino acid homeostasis. Here, we discuss the key roles that amino acids, along with energy (ATP, glucose) and oxygen, are playing in cellular growth and proliferation. We further explore how sophisticated methods are employed by cells to sense intracellular amino acid concentrations, how amino acids can act as a switch to dictate the temporal and spatial activation of anabolic and catabolic processes and how autophagy contributes to the replenishment of free amino acids, all to ensure cell survival. Relevance of these molecular processes to cellular and organismal physiology and pathology is also discussed.

Magnesium Reduces Hepatic Lipid Accumulation in Yellow Catfish (Pelteobagrus fulvidraco) and Modulates Lipogenesis and Lipolysis via PPARA, JAK-STAT, and AMPK Pathways in Hepatocytes.

Science.gov (United States)

Wei, Chuan-Chuan; Wu, Kun; Gao, Yan; Zhang, Li-Han; Li, Dan-Dan; Luo, Zhi

2017-06-01

Background: Magnesium influences hepatic lipid deposition in vertebrates, but the underlying mechanism is unknown. Objective: We used yellow catfish and their isolated hepatocytes to test the hypothesis that magnesium influences lipid deposition by modulating lipogenesis and lipolysis. Methods: Juvenile yellow catfish (mean ± SEM weight: 3.43 ± 0.02 g, 3 mo old, mixed sex) were fed a 0.14- (low), 0.87- (intermediate) or 2.11- (high) g Mg/kg diet for 56 d. Primary hepatocytes were incubated for 48 h in control or MgSO 4 -containing medium with or without 2-h pretreatment with an inhibitor (AG490, GW6471, or Compound C). Growth performance, cell viability, triglyceride (TG) concentrations, and expression of enzymes and genes involved in lipid metabolism were measured. Results: Compared with fish fed low magnesium, those fed intermediate or high magnesium had lower hepatic lipids (18%, 22%) and 6-phosphogluconate dehydrogenase (6PGD; 3.7%, 3.8%) and malic enzyme (ME; 35%, 48%) activities and greater mRNA levels of the lipolytic genes adipose triacylglyceride lipase ( atgl ; 82% and 1.7-fold) and peroxisome proliferator-activated receptor ( ppara ; 18% and 1.0-fold), respectively ( P magnesium were higher (24% to 3.1-fold, P magnesium. Compared with cells incubated with MgSO 4 alone, those incubated with MgSO 4 and pretreated with AG490, GW6471, or Compound C had greater TG concentrations (42%, 31%, or 56%), g6pd (98%, 59%, or 51%), 6pgd (68%, 73%, or 32%) mRNA expression, and activities of G6PD (35%, 45%, or 16%) and ME (1.5-fold, 1.3-fold, or 13%), and reduced upregulation (61%, 25%, or 45%) of the lipolytic gene, atgl ( P Magnesium reduced hepatic lipid accumulation in yellow catfish and the variation might be attributed to inhibited lipogenesis and increased lipolysis. PPARA, JAK-STAT, and AMPK pathways mediated the magnesium-induced changes in lipid deposition and metabolism. These results offer new insight into magnesium nutrition in vertebrates. © 2017

A Phospholipid-Protein Complex from Krill with Antioxidative and Immunomodulating Properties Reduced Plasma Triacylglycerol and Hepatic Lipogenesis in Rats

Directory of Open Access Journals (Sweden)

Marie S. Ramsvik

2015-07-01

Full Text Available Dietary intake of marine omega-3 polyunsaturated fatty acids (n-3 PUFAs can change the plasma profile from atherogenic to cardioprotective. In addition, there is growing evidence that proteins of marine origin may have health benefits. We investigated a phospholipid-protein complex (PPC from krill that is hypothesized to influence lipid metabolism, inflammation, and redox status. Male Wistar rats were fed a control diet (2% soy oil, 8% lard, 20% casein, or diets where corresponding amounts of casein and lard were replaced with PPC at 3%, 6%, or 11% (wt %, for four weeks. Dietary supplementation with PPC resulted in significantly lower levels of plasma triacylglycerols in the 11% PPC-fed group, probably due to reduced hepatic lipogenesis. Plasma cholesterol levels were also reduced at the highest dose of PPC. In addition, the plasma and liver content of n-3 PUFAs increased while n-6 PUFAs decreased. This was associated with increased total antioxidant capacity in plasma and increased liver gene expression of mitochondrial superoxide dismutase (Sod2. Finally, a reduced plasma level of the inflammatory mediator interleukin-2 (IL-2 was detected in the PPC-fed animals. The present data show that PPC has lipid-lowering effects in rats, and may modulate risk factors related to cardiovascular disease progression.

STATISTIC MODEL OF DYNAMIC DELAY AND DROPOUT ON CELLULAR DATA NETWORKED CONTROL SYSTEM

Directory of Open Access Journals (Sweden)

MUHAMMAD A. MURTI

2017-07-01

Full Text Available Delay and dropout are important parameters influence overall control performance in Networked Control System (NCS. The goal of this research is to find a model of delay and dropout of data communication link in the NCS. Experiments have been done in this research to a water level control of boiler tank as part of the NCS based on internet communication network using High Speed Packet Access (HSPA cellular technology. By this experiments have been obtained closed-loop system response as well as data delay and dropout of data packets. This research contributes on modeling of the NCS which is combination of controlled plant and data communication link. Another contribution is statistical model of delay and dropout on the NCS.

Coordination of Heparan Sulfate Proteoglycans with Wnt Signaling To Control Cellular Migrations and Positioning in Caenorhabditis elegans.

Science.gov (United States)

Saied-Santiago, Kristian; Townley, Robert A; Attonito, John D; da Cunha, Dayse S; Díaz-Balzac, Carlos A; Tecle, Eillen; Bülow, Hannes E

2017-08-01

Heparan sulfates (HS) are linear polysaccharides with complex modification patterns, which are covalently bound via conserved attachment sites to core proteins to form heparan sulfate proteoglycans (HSPGs). HSPGs regulate many aspects of the development and function of the nervous system, including cell migration, morphology, and network connectivity. HSPGs function as cofactors for multiple signaling pathways, including the Wnt-signaling molecules and their Frizzled receptors. To investigate the functional interactions among the HSPG and Wnt networks, we conducted genetic analyses of each, and also between these networks using five cellular migrations in the nematode Caenorhabditis elegans We find that HSPG core proteins act genetically in a combinatorial fashion dependent on the cellular contexts. Double mutant analyses reveal distinct redundancies among HSPGs for different migration events, and different cellular migrations require distinct heparan sulfate modification patterns. Our studies reveal that the transmembrane HSPG SDN-1/Syndecan functions within the migrating cell to promote cellular migrations, while the GPI-linked LON-2/Glypican functions cell nonautonomously to establish the final cellular position. Genetic analyses with the Wnt-signaling system show that (1) a given HSPG can act with different Wnts and Frizzled receptors, and that (2) a given Wnt/Frizzled pair acts with different HSPGs in a context-dependent manner. Lastly, we find that distinct HSPG and Wnt/Frizzled combinations serve separate functions to promote cellular migration and establish position of specific neurons. Our studies suggest that HSPGs use structurally diverse glycans in coordination with Wnt-signaling pathways to control multiple cellular behaviors, including cellular and axonal migrations and, cellular positioning. Copyright © 2017 by the Genetics Society of America.

Inhibition of human copper trafficking by a small molecule significantly attenuates cancer cell proliferation

Science.gov (United States)

Wang, Jing; Luo, Cheng; Shan, Changliang; You, Qiancheng; Lu, Junyan; Elf, Shannon; Zhou, Yu; Wen, Yi; Vinkenborg, Jan L.; Fan, Jun; Kang, Heebum; Lin, Ruiting; Han, Dali; Xie, Yuxin; Karpus, Jason; Chen, Shijie; Ouyang, Shisheng; Luan, Chihao; Zhang, Naixia; Ding, Hong; Merkx, Maarten; Liu, Hong; Chen, Jing; Jiang, Hualiang; He, Chuan

2015-12-01

Copper is a transition metal that plays critical roles in many life processes. Controlling the cellular concentration and trafficking of copper offers a route to disrupt these processes. Here we report small molecules that inhibit the human copper-trafficking proteins Atox1 and CCS, and so provide a selective approach to disrupt cellular copper transport. The knockdown of Atox1 and CCS or their inhibition leads to a significantly reduced proliferation of cancer cells, but not of normal cells, as well as to attenuated tumour growth in mouse models. We show that blocking copper trafficking induces cellular oxidative stress and reduces levels of cellular ATP. The reduced level of ATP results in activation of the AMP-activated protein kinase that leads to reduced lipogenesis. Both effects contribute to the inhibition of cancer cell proliferation. Our results establish copper chaperones as new targets for future developments in anticancer therapies.

Adaptive pressure-controlled cellular structures for shape morphing I: design and analysis

International Nuclear Information System (INIS)

Luo, Quantian; Tong, Liyong

2013-01-01

This work investigates adaptive bio-inspired pressure cellular structures for shape morphing. Optimum designs for cellular structures with void and pressure cells are proposed and then structural analyses are conducted. In the present design, a unit cell is comprised of straight and curved walls. When compressed air is pumped into a pressure cell, the curved walls deform in bending due to the pressure difference in two adjacent cells that leads to overall structural deformation in extension. One-dimensional actuation strain up to 35% can be theoretically achieved. In part I, we present basic design concepts and cellular mechanics. Unlike conventional structural analysis for cellular structures, a statically indeterminate unit cell is considered and novel analytical formulations are derived for the present pressurized cellular structures in linear and nonlinear analyses. In part II, we will present experimental testing and finite element analysis to demonstrate the feasibility of the present pressurized cellular actuators for morphing wings and to validate the present cellular mechanics formulations. (paper)

Insulin Treatment Cannot Promote Lipogenesis in Rat Fetal Lung in Gestational Diabetes Mellitus Because of Failure to Redress the Imbalance Among SREBP-1, SCAP, and INSIG-1.

Science.gov (United States)

Li, Jinyan; Qian, Guanhua; Zhong, Xiaocui; Yu, Tinghe

2018-03-01

Gestational diabetes mellitus (GDM) has a higher incidence of neonatal respiratory distress syndrome, and lipogenesis is required for the synthesis of pulmonary surfactants. The aim of this study was to determine the effect of insulin treatment in GDM on the production of lipids in the lungs of fetal rats. GDM was induced by streptozotocin, and insulin was used to manage diabetes. Type II alveolar epithelial cells (AEC II), bronchoalveolar lavage fluid (BALF), and lung tissues of the neonatal rats were sampled for analyses. Insulin treatment could not decrease plasma glucose to normal level at a later gestational stage. Lipids/phospholipids in AEC II, BALF, and lung tissues decreased in GDM, and insulin treatment could not increase the levels; quantitative PCR and western blotting demonstrated a lower level of sterol regulator element-binding protein 1 (SREBP-1), SREBP cleavage-activating protein (SCAP), and insulin-induced gene 1 (INSIG-1) in GDM, but insulin treatment upregulated only SREBP-1. Nuclear translocation of the SREBP-1 protein in AEC II was impaired in GDM, which could not be ameliorated by insulin treatment. These findings indicated that insulin treatment in GDM cannot promote lipogenesis in the fetal lung because of failure to redress the imbalance among SREBP-1, SCAP, and INSIG-1.

Molecular and Cellular Signaling

CERN Document Server

Beckerman, Martin

2005-01-01

A small number of signaling pathways, no more than a dozen or so, form a control layer that is responsible for all signaling in and between cells of the human body. The signaling proteins belonging to the control layer determine what kinds of cells are made during development and how they function during adult life. Malfunctions in the proteins belonging to the control layer are responsible for a host of human diseases ranging from neurological disorders to cancers. Most drugs target components in the control layer, and difficulties in drug design are intimately related to the architecture of the control layer. Molecular and Cellular Signaling provides an introduction to molecular and cellular signaling in biological systems with an emphasis on the underlying physical principles. The text is aimed at upper-level undergraduates, graduate students and individuals in medicine and pharmacology interested in broadening their understanding of how cells regulate and coordinate their core activities and how diseases ...

Forward Link Power Control Strategy and its Optimum Issue in CDMA Cellular Networks

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

In this paper, we propose a theoretical method in order to estimate the forward link outage probability and user capacity of a cellular system which are based on IS-95 CDMA standard, especialy impact of power control strategy and voice activity monitoring in the system under long-term fading effects, in which the light and heavy fadings are considered. According to the numerical results obtained in this paper, the power control strategy leads to approximately the threefold user capacity in contrast to the situation without power control strategy. The reults are compared with Interference-to-Signal Ratio (ISR) driven power control scheme[6][9] which can be used only for simulation of the system. The power control strategy not only improves the desired signal to the interference ratio in the reference user's receiver, but also offers uniform service to the user wherever it is located in the cell.

Periodic 48 h feed withdrawal improves glucose tolerance in growing pigs by enhancing adipogenesis and lipogenesis

Directory of Open Access Journals (Sweden)

Mir Priya S

2012-02-01

lipogenesis rather than number, affecting glucose metabolism and may have implications in drug-free control of metabolic syndrome symptoms.

Release Properties and Cellular Uptake in Caco-2 Cells of Size-Controlled Chitosan Nanoparticles.

Science.gov (United States)

Je, Hyun Jeong; Kim, Eun Suh; Lee, Ji-Soo; Lee, Hyeon Gyu

2017-12-20

The influences of particle size on the physicochemical, release, and cellular uptake properties of chitosan nanoparticles (CSNPs) were investigated. Ionotropic CSNPs of different sizes (200-1000 nm) loaded with two model core materials (resveratrol or coumarin-6) were prepared using tripolyphosphate and carrageenan as cross-linkers. With an increase of particle size, zeta potential (34.6 ± 0.5 to 51.1 ± 0.9) and entrapment efficiency (14.9 ± 1.4 to 40.9 ± 1.9) of the CSNPs were significantly (p cellular uptake of CSNPs were significantly increased from 3.70 ± 0.03 to 5.24 ± 0.20 with an increase of particle size from 200 to 600 nm, whereas those significantly decreased from 5.24 ± 0.20 to 4.55 ± 0.2 for particles larger than 600 nm in transwell assay. Moreover, much the same uptake patterns were also observed in confocal microscopy and flow cytometry. Investigation of cellular uptake of CSNPs revealed positive correlations between ZP and EE and indicated the effects of complex factors of nanoparticles other than size. These results provide a better understanding of CSNPs absorption and raises the possibility of controlling alternative nanoparticle properties to enhance bioavailability.

Exendin-4 Inhibits Hepatic Lipogenesis by Increasing β-Catenin Signaling.

Directory of Open Access Journals (Sweden)

Mi Hae Seo

Full Text Available The aim of this study is to investigate whether the beneficial effect of exendin-4 on hepatic steatosis is mediated by β-catenin signaling. After the HepG2 human hepatoma cells were treated with PA for 24 hours, total triglycerides levels were increased in a dose-dependent manner, and the expression levels of perilipin family members were upregulated in cells treated with 400 μM PA. For our in vitro model of hepatic steatosis, HepG2 cells were treated with 400 μM palmitic acid (PA in the presence or absence of 100 nM exendin-4 for 24 hours. PA increased the expression of lipogenic genes, such as sterol regulatory element-binding protein 1c (SREBP-1c, peroxisome proliferator-activated receptor gamma (PPARγ, stearoyl-CoA desaturase 1 (SCD1, fatty acid synthase (FAS, and acetyl-CoA carboxylase (ACC and triglyceride synthesis-involved genes, such as diacylglycerol acyltransferase 1 (DGAT1 and diacylglycerol acyltransferase 2 (DGAT2 in HepG2 cells, whereas exendin-4 treatment significantly prevented the upregulation of SREBP-1c, PPARγ, SCD1, FAS, ACC, DGAT1 and DGAT2. Moreover, exendin-4 treatment increased the expression of phosphorylated glycogen synthase kinase-3 beta (GSK-3β in the cytosolic fraction and the expression of β-catenin and transcription factor 4 (TCF4 in the nuclear fraction. In addition, siRNA-mediated inhibition of β-catenin upregulated the expression of lipogenic transcription factors. The protective effects of exendin-4 on intracellular triglyceride content and total triglyceride levels were not observed in cells treated with the β-catenin inhibitor IWR-1. These data suggest that exendin-4 treatment improves hepatic steatosis by inhibiting lipogenesis via activation of Wnt/β-catenin signaling.

The diabetes medication Canagliflozin reduces cancer cell proliferation by inhibiting mitochondrial complex-I supported respiration

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Linda A. Villani

2016-10-01

Full Text Available Objective: The sodium-glucose transporter 2 (SGLT2 inhibitors Canagliflozin and Dapagliflozin are recently approved medications for type 2 diabetes. Recent studies indicate that SGLT2 inhibitors may inhibit the growth of some cancer cells but the mechanism(s remain unclear. Methods: Cellular proliferation and clonogenic survival were used to assess the sensitivity of prostate and lung cancer cell growth to the SGLT2 inhibitors. Oxygen consumption, extracellular acidification rate, cellular ATP, glucose uptake, lipogenesis, and phosphorylation of AMP-activated protein kinase (AMPK, acetyl-CoA carboxylase, and the p70S6 kinase were assessed. Overexpression of a protein that maintains complex-I supported mitochondrial respiration (NDI1 was used to establish the importance of this pathway for mediating the anti-proliferative effects of Canagliflozin. Results: Clinically achievable concentrations of Canagliflozin, but not Dapagliflozin, inhibit cellular proliferation and clonogenic survival of prostate and lung cancer cells alone and in combination with ionizing radiation and the chemotherapy Docetaxel. Canagliflozin reduced glucose uptake, mitochondrial complex-I supported respiration, ATP, and lipogenesis while increasing the activating phosphorylation of AMPK. The overexpression of NDI1 blocked the anti-proliferative effects of Canagliflozin indicating reductions in mitochondrial respiration are critical for anti-proliferative actions. Conclusion: These data indicate that like the biguanide metformin, Canagliflozin not only lowers blood glucose but also inhibits complex-I supported respiration and cellular proliferation in prostate and lung cancer cells. These observations support the initiation of studies evaluating the clinical efficacy of Canagliflozin on limiting tumorigenesis in pre-clinical animal models as well epidemiological studies on cancer incidence relative to other glucose lowering therapies in clinical populations. Keywords: AMP

Admission Control Threshold in Cellular Relay Networks with Power Adjustment

Directory of Open Access Journals (Sweden)

Lee Ki-Dong

2009-01-01

Full Text Available Abstract In the cellular network with relays, the mobile station can benefit from both coverage extension and capacity enhancement. However, the operation complexity increases as the number of relays grows up. Furthermore, in the cellular network with cooperative relays, it is even more complex because of an increased dimension of signal-to-noise ratios (SNRs formed in the cooperative wireless transmission links. In this paper, we propose a new method for admission capacity planning in a cellular network using a cooperative relaying mechanism called decode-and-forward. We mathematically formulate the dropping ratio using the randomness of "channel gain." With this, we formulate an admission threshold planning problem as a simple optimization problem, where we maximize the accommodation capacity (in number of connections subject to two types of constraints. (1 A constraint that the sum of the transmit powers of the source node and relay node is upper-bounded where both nodes can jointly adjust the transmit power. (2 A constraint that the dropping ratio is upper-bounded by a certain threshold value. The simplicity of the problem formulation facilitates its solution in real-time. We believe that the proposed planning method can provide an attractive guideline for dimensioning a cellular relay network with cooperative relays.

Cellular protein quality control and the evolution of aggregates in spinocerebellar ataxia type 3 (SCA3)

NARCIS (Netherlands)

Seidel, K.; Meister, M.; Dugbartey, G. J.; Zijlstra, M. P.; Vinet, J.; Brunt, E. R. P.; van Leeuwen, F. W.; Rueb, U.; Kampinga, H. H.; den Dunnen, W. F. A.

2012-01-01

K. Seidel, M. Meister, G. J. Dugbartey, M. P. Zijlstra, J. Vinet, E. R. P. Brunt, F. W. van Leeuwen, U. Rub, H. H. Kampinga and W. F. A. den Dunnen (2012) Neuropathology and Applied Neurobiology38, 548558 Cellular protein quality control and the evolution of aggregates in spinocerebellar ataxia type

Adipocyte-specific protein tyrosine phosphatase 1B deletion increases lipogenesis, adipocyte cell size and is a minor regulator of glucose homeostasis.

Directory of Open Access Journals (Sweden)

Carl Owen

Full Text Available Protein tyrosine phosphatase 1B (PTP1B, a key negative regulator of leptin and insulin signaling, is positively correlated with adiposity and contributes to insulin resistance. Global PTP1B deletion improves diet-induced obesity and glucose homeostasis via enhanced leptin signaling in the brain and increased insulin signaling in liver and muscle. However, the role of PTP1B in adipocytes is unclear, with studies demonstrating beneficial, detrimental or no effect(s of adipose-PTP1B-deficiency on body mass and insulin resistance. To definitively establish the role of adipocyte-PTP1B in body mass regulation and glucose homeostasis, adipocyte-specific-PTP1B knockout mice (adip-crePTP1B(-/- were generated using the adiponectin-promoter to drive Cre-recombinase expression. Chow-fed adip-crePTP1B(-/- mice display enlarged adipocytes, despite having similar body weight/adiposity and glucose homeostasis compared to controls. High-fat diet (HFD-fed adip-crePTP1B(-/- mice display no differences in body weight/adiposity but exhibit larger adipocytes, increased circulating glucose and leptin levels, reduced leptin sensitivity and increased basal lipogenesis compared to controls. This is associated with decreased insulin receptor (IR and Akt/PKB phosphorylation, increased lipogenic gene expression and increased hypoxia-induced factor-1-alpha (Hif-1α expression. Adipocyte-specific PTP1B deletion does not beneficially manipulate signaling pathways regulating glucose homeostasis, lipid metabolism or adipokine secretion in adipocytes. Moreover, PTP1B does not appear to be the major negative regulator of the IR in adipocytes.

Global transcriptome profiling identifies KLF15 and SLC25A10 as modifiers of adipocytes insulin sensitivity in obese women.

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Agné Kulyté

Full Text Available Although the mechanisms linking obesity to insulin resistance (IR and type 2 diabetes (T2D are not entirely understood, it is likely that alterations of adipose tissue function are involved. The aim of this study was to identify new genes controlling insulin sensitivity in adipocytes from obese women with either insulin resistant (OIR or sensitive (OIS adipocytes. Insulin sensitivity was first determined by measuring lipogenesis in isolated adipocytes from abdominal subcutaneous white adipose tissue (WAT in a large observational study. Lipogenesis was measured under conditions where glucose transport was the rate limiting step and reflects in vivo insulin sensitivity. We then performed microarray-based transcriptome profiling on subcutaneous WAT specimen from a subgroup of 9 lean, 21 OIS and 18 obese OIR women. We could identify 432 genes that were differentially expressed between the OIR and OIS group (FDR ≤5%. These genes are enriched in pathways related to glucose and amino acid metabolism, cellular respiration, and insulin signaling, and include genes such as SLC2A4, AKT2, as well as genes coding for enzymes in the mitochondria respiratory chain. Two IR-associated genes, KLF15 encoding a transcription factor and SLC25A10 encoding a dicarboxylate carrier, were selected for functional evaluation in adipocytes differentiated in vitro. Knockdown of KLF15 and SLC25A10 using siRNA inhibited insulin-stimulated lipogenesis in adipocytes. Transcriptome profiling of siRNA-treated cells suggested that KLF15 might control insulin sensitivity by influencing expression of PPARG, PXMP2, AQP7, LPL and genes in the mitochondrial respiratory chain. Knockdown of SLC25A10 had only modest impact on the transcriptome, suggesting that it might directly influence insulin sensitivity in adipocytes independently of transcription due to its important role in fatty acid synthesis. In summary, this study identifies novel genes associated with insulin sensitivity in

Adaptive pressure-controlled cellular structures for shape morphing: II. Numerical and experimental validation

International Nuclear Information System (INIS)

Luo, Quantian; Tong, Liyong

2013-01-01

This part presents finite element analysis to verify the present formulations on mechanics of the pressurized cellular structures derived in Part I and experimental testing for a pressurized cellular actuator to demonstrate feasibility and realization of the proposed pressurized cellular structures. Linear and nonlinear finite element analyses are implemented in a commercial finite element analysis package and the numerical results are compared with those of the novel formulations given in Part I. A pressurized cellular structure specimen with 3 cells is fabricated and tested. The fabricated 3-cell cellular structure is capable of yielding a free actuation strain of around 24%. The measured pressure-induced displacement and blocking force compare favorably with the numerical results predicted by the finite element analysis and analytical formulations. (paper)

Cellular specificity of HIV-1 replication can be controlled by LTR sequences

International Nuclear Information System (INIS)

Reed-Inderbitzin, Edward; Maury, Wendy

2003-01-01

Two well-established determinants of retroviral tropism are envelope sequences that regulate entry and LTR sequences that can regulate viral expression in a cell-specific manner. Studies with human immunodeficiency virus-1 (HIV-1) have demonstrated that tropism of this virus maps primarily to variable envelope sequences. Studies have demonstrated that T cell and macrophage-specific transcription factor binding motifs exist in the upstream region of the LTR U3; however, the ability of the core enhancer/promoter proximal elements (two NF-κB and three Sp1 sites) to function well in macrophages and T cells have led many to conclude that HIV LTR sequences are not primary determinants of HIV tropism. To determine if cellular specificity could be imparted to HIV by the core enhancer elements, the enhancer/promoter proximal region of the HIV LTR was substituted with motifs that control gene expression in a myeloid-specific manner. The enhancer region from equine infectious anemia virus (EIAV) when substituted for the HIV enhancer/promoter proximal region was found to drive expression in a macrophage-specific manner and was responsive to HIV Tat. The addition of a 5' methylation-dependent binding site (MDBP) and a promoter proximal Sp1 motif increased expression without altering cellular specificity. Spacing between the promoter proximal region and the TATA box was also found to influence LTR activity. Infectivity studies using chimeric LTRs within the context of a dual-tropic infectious molecular clone established that these LTRs directed HIV replication and production of infectious virions in macrophages but not primary T cells or T cell lines. This investigation demonstrates that cellular specificity can be imparted onto HIV-1 replication at the level of viral transcription and not entry

The imperative for controlled mechanical stresses in unraveling cellular mechanisms of mechanotransduction

Directory of Open Access Journals (Sweden)

Sorkin Adam M

2006-05-01

Full Text Available Abstract Background In vitro mechanotransduction studies are designed to elucidate cell behavior in response to a well-defined mechanical signal that is imparted to cultured cells, e.g. through fluid flow. Typically, flow rates are calculated based on a parallel plate flow assumption, to achieve a targeted cellular shear stress. This study evaluates the performance of specific flow/perfusion chambers in imparting the targeted stress at the cellular level. Methods To evaluate how well actual flow chambers meet their target stresses (set for 1 and 10 dyn/cm2 for this study at a cellular level, computational models were developed to calculate flow velocity components and imparted shear stresses for a given pressure gradient. Computational predictions were validated with micro-particle image velocimetry (μPIV experiments. Results Based on these computational and experimental studies, as few as 66% of cells seeded along the midplane of commonly implemented flow/perfusion chambers are subjected to stresses within ±10% of the target stress. In addition, flow velocities and shear stresses imparted through fluid drag vary as a function of location within each chamber. Hence, not only a limited number of cells are exposed to target stress levels within each chamber, but also neighboring cells may experience different flow regimes. Finally, flow regimes are highly dependent on flow chamber geometry, resulting in significant variation in magnitudes and spatial distributions of stress between chambers. Conclusion The results of this study challenge the basic premise of in vitro mechanotransduction studies, i.e. that a controlled flow regime is applied to impart a defined mechanical stimulus to cells. These results also underscore the fact that data from studies in which different chambers are utilized can not be compared, even if the target stress regimes are comparable.

Power Control for D2D Underlay Cellular Networks With Channel Uncertainty

KAUST Repository

Memmi, Amen; Rezki, Zouheir; Alouini, Mohamed-Slim

2016-01-01

Device-to-device (D2D) communications underlying the cellular infrastructure are a technology that have been proposed recently as a promising solution to enhance cellular network capabilities. It improves spectrum utilization, overall throughput

STAT proteins: from normal control of cellular events to tumorigenesis.

Science.gov (United States)

Calò, Valentina; Migliavacca, Manuela; Bazan, Viviana; Macaluso, Marcella; Buscemi, Maria; Gebbia, Nicola; Russo, Antonio

2003-11-01

Signal transducers and activators of transcription (STAT) proteins comprise a family of transcription factors latent in the cytoplasm that participate in normal cellular events, such as differentiation, proliferation, cell survival, apoptosis, and angiogenesis following cytokine, growth factor, and hormone signaling. STATs are activated by tyrosine phosphorylation, which is normally a transient and tightly regulates process. Nevertheless, several constitutively activated STATs have been observed in a wide number of human cancer cell lines and primary tumors, including blood malignancies and solid neoplasias. STATs can be divided into two groups according to their specific functions. One is made up of STAT2, STAT4, and STAT6, which are activated by a small number of cytokines and play a distinct role in the development of T-cells and in IFNgamma signaling. The other group includes STAT1, STAT3, and STAT5, activated in different tissues by means of a series of ligands and involved in IFN signaling, development of the mammary gland, response to GH, and embriogenesis. This latter group of STATS plays an important role in controlling cell-cycle progression and apoptosis and thus contributes to oncogenesis. Although an increased expression of STAT1 has been observed in many human neoplasias, this molecule can be considered a potential tumor suppressor, since it plays an important role in growth arrest and in promoting apoptosis. On the other hand, STAT3 and 5 are considered as oncogenes, since they bring about the activation of cyclin D1, c-Myc, and bcl-xl expression, and are involved in promoting cell-cycle progression, cellular transformation, and in preventing apoptosis.

A nucleator arms race: cellular control of actin assembly.

Science.gov (United States)

Campellone, Kenneth G; Welch, Matthew D

2010-04-01

For over a decade, the actin-related protein 2/3 (ARP2/3) complex, a handful of nucleation-promoting factors and formins were the only molecules known to directly nucleate actin filament formation de novo. However, the past several years have seen a surge in the discovery of mammalian proteins with roles in actin nucleation and dynamics. Newly recognized nucleation-promoting factors, such as WASP and SCAR homologue (WASH), WASP homologue associated with actin, membranes and microtubules (WHAMM), and junction-mediating regulatory protein (JMY), stimulate ARP2/3 activity at distinct cellular locations. Formin nucleators with additional biochemical and cellular activities have also been uncovered. Finally, the Spire, cordon-bleu and leiomodin nucleators have revealed new ways of overcoming the kinetic barriers to actin polymerization.

A Herbal Formula HT048, Citrus unshiu and Crataegus pinnatifida, Prevents Obesity by Inhibiting Adipogenesis and Lipogenesis in 3T3-L1 Preadipocytes and HFD-Induced Obese Rats

Directory of Open Access Journals (Sweden)

Yoon Hee Lee

2015-05-01

Full Text Available HT048 is a combination composed of Crataegus pinnatifida leaf and Citrus unshiu peel extracts. This study aimed to investigate potential anti-obesity effect of the combination. The 3T3-L1 adipocytes were treated with different doses of HT048 and triglyceride accumulation, glycerol release and adipogenesis-related genes were analyzed. For in vivo study, male Sprague Dawley rats were divided according to experimental diets: the chow diet group, the high-fat diet (HFD group, the HFD supplemented with orlistat group, the HFD supplemented with HT048 group (0.2% or 0.4% for 12 weeks. We measured the body weight, serum lipid levels and the expression of genes involved lipid metabolism. HT048 treatment dose-dependently suppressed adipocyte differentiation and stimulated glycerol release. The expressions of PPARγ and C/EBPα mRNA were decreased by HT048 treatment in adipocytes. HT048 supplementation significantly reduced the body and fat weights in vivo. Serum lipid levels were significantly lower in the HT048 supplemented groups than those of the HFD group. Expression of the hepatic lipogenesis-related genes were decreased and expression of the β-oxidation-related genes were increased in rats fed HT048 compared to that of animals fed HFD. These results suggest that HT048 has a potential benefit in preventing obesity through the inhibition of lipogenesis and adipogenesis.

Validation of self-reported cellular phone use

DEFF Research Database (Denmark)

Samkange-Zeeb, Florence; Berg, Gabriele; Blettner, Maria

2004-01-01

BACKGROUND: In recent years, concern has been raised over possible adverse health effects of cellular telephone use. In epidemiological studies of cancer risk associated with the use of cellular telephones, the validity of self-reported cellular phone use has been problematic. Up to now there is ......BACKGROUND: In recent years, concern has been raised over possible adverse health effects of cellular telephone use. In epidemiological studies of cancer risk associated with the use of cellular telephones, the validity of self-reported cellular phone use has been problematic. Up to now...... there is very little information published on this subject. METHODS: We conducted a study to validate the questionnaire used in an ongoing international case-control study on cellular phone use, the "Interphone study". Self-reported cellular phone use from 68 of 104 participants who took part in our study...... was compared with information derived from the network providers over a period of 3 months (taken as the gold standard). RESULTS: Using Spearman's rank correlation, the correlation between self-reported phone use and information from the network providers for cellular phone use in terms of the number of calls...

Algorithm for cellular reprogramming.

Science.gov (United States)

Ronquist, Scott; Patterson, Geoff; Muir, Lindsey A; Lindsly, Stephen; Chen, Haiming; Brown, Markus; Wicha, Max S; Bloch, Anthony; Brockett, Roger; Rajapakse, Indika

2017-11-07

The day we understand the time evolution of subcellular events at a level of detail comparable to physical systems governed by Newton's laws of motion seems far away. Even so, quantitative approaches to cellular dynamics add to our understanding of cell biology. With data-guided frameworks we can develop better predictions about, and methods for, control over specific biological processes and system-wide cell behavior. Here we describe an approach for optimizing the use of transcription factors (TFs) in cellular reprogramming, based on a device commonly used in optimal control. We construct an approximate model for the natural evolution of a cell-cycle-synchronized population of human fibroblasts, based on data obtained by sampling the expression of 22,083 genes at several time points during the cell cycle. To arrive at a model of moderate complexity, we cluster gene expression based on division of the genome into topologically associating domains (TADs) and then model the dynamics of TAD expression levels. Based on this dynamical model and additional data, such as known TF binding sites and activity, we develop a methodology for identifying the top TF candidates for a specific cellular reprogramming task. Our data-guided methodology identifies a number of TFs previously validated for reprogramming and/or natural differentiation and predicts some potentially useful combinations of TFs. Our findings highlight the immense potential of dynamical models, mathematics, and data-guided methodologies for improving strategies for control over biological processes. Copyright © 2017 the Author(s). Published by PNAS.

Leading research on artificial techniques controlling cellular function; Saibo zoshoku seigyo gijutsu no sendo kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

Advanced research and its applicability were surveyed to apply the advanced functional cells to industry. The basic target was set to develop, produce, control and utilize the functional cells, such as intelligent materials and self-regulation bioreactors. The regulation factors regarding apotosis, which is a process of cell suicide programmed within the cell itself of multicellular organisms, cell cycle and aging/ageless were investigated. Furthermore, the function of regulatory factors was investigated at the protein level. Injection of factors regulating cellular function and tissue engineering required for the regulation of cell proliferation were investigated. Tissue engineering is considered to be the intracellular regulation by gene transduction and the extracellular regulation by culture methods, such as coculture. Analysis methods for cell proliferation and function of living cells were investigated using the probes recognizing molecular structure. Novel biomaterials, artificial organ systems, cellular therapy and useful materials were investigated for utilizing the regulation techniques of cell proliferation. 425 refs., 85 figs., 9 tabs.

A study of lipogenesis de novo: kinetics of tritiated water 3H incorporation in vivo into fatty acids and total lipids of the liver, plasma, adipose tissue and carcass of the male rat

International Nuclear Information System (INIS)

Gandemer, Gille; Pascal, Gerard; Durand, Georges

1980-01-01

Tritiated water 3 H, injected by intraperitoneal route into 7-week old male Rats, was incorporated into lipids synthesized de novo. The Rats were killed 0, 3, 7, 10, 15, 30, 60 and 120 min. after tracer injection. The results show that an optimal interval of about 10 min. between tracer injection and animal sacrifice was necessary to obtain a correct estimate of lipogenesis de novo by avoiding intertissue exchanges [fr

Cellular immobilization within microfluidic microenvironments: dielectrophoresis with polyelectrolyte multilayers.

Science.gov (United States)

Forry, Samuel P; Reyes, Darwin R; Gaitan, Michael; Locascio, Laurie E

2006-10-25

The development of biomimetic microenvironments will improve cell culture techniques by enabling in vitro cell cultures that mimic in vivo behavior; however, experimental control over attachment, cellular position, or intercellular distances within such microenvironments remains challenging. We report here the rapid and controllable immobilization of suspended mammalian cells within microfabricated environments using a combination of electronic (dielectrophoresis, DEP) and chemical (polyelectrolyte multilayers, PEMS) forces. While cellular position within the microsystem is rapidly patterned via intermittent DEP trapping, persistent adhesion after removal of electronic forces is enabled by surface treatment with PEMS that are amenable to cellular attachment. In contrast to DEP trapping alone, persistent adhesion enables the soluble microenvironment to be systematically varied, facilitating the use of soluble probes of cell state and enabling cellular characterization in response to various soluble stimuli.

Controlling Depth of Cellular Quiescence by an Rb-E2F Network Switch

Directory of Open Access Journals (Sweden)

Jungeun Sarah Kwon

2017-09-01

Full Text Available Quiescence is a non-proliferative cellular state that is critical to tissue repair and regeneration. Although often described as the G0 phase, quiescence is not a single homogeneous state. As cells remain quiescent for longer durations, they move progressively deeper and display a reduced sensitivity to growth signals. Deep quiescent cells, unlike senescent cells, can still re-enter the cell cycle under physiological conditions. Mechanisms controlling quiescence depth are poorly understood, representing a currently underappreciated layer of complexity in growth control. Here, we show that the activation threshold of a Retinoblastoma (Rb-E2F network switch controls quiescence depth. Particularly, deeper quiescent cells feature a higher E2F-switching threshold and exhibit a delayed traverse through the restriction point (R-point. We further show that different components of the Rb-E2F network can be experimentally perturbed, following computer model predictions, to coarse- or fine-tune the E2F-switching threshold and drive cells into varying quiescence depths.

Cellularized Cellular Solids via Freeze-Casting.

Science.gov (United States)

Christoph, Sarah; Kwiatoszynski, Julien; Coradin, Thibaud; Fernandes, Francisco M

2016-02-01

The elaboration of metabolically active cell-containing materials is a decisive step toward the successful application of cell based technologies. The present work unveils a new process allowing to simultaneously encapsulate living cells and shaping cell-containing materials into solid-state macroporous foams with precisely controlled morphology. Our strategy is based on freeze casting, an ice templating materials processing technique that has recently emerged for the structuration of colloids into macroporous materials. Our results indicate that it is possible to combine the precise structuration of the materials with cellular metabolic activity for the model organism Saccharomyces cerevisiae. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cellular transport of l-arginine determines renal medullary blood flow in control rats, but not in diabetic rats despite enhanced cellular uptake capacity.

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Persson, Patrik; Fasching, Angelica; Teerlink, Tom; Hansell, Peter; Palm, Fredrik

2017-02-01

Diabetes mellitus is associated with decreased nitric oxide bioavailability thereby affecting renal blood flow regulation. Previous reports have demonstrated that cellular uptake of l-arginine is rate limiting for nitric oxide production and that plasma l-arginine concentration is decreased in diabetes. We therefore investigated whether regional renal blood flow regulation is affected by cellular l-arginine uptake in streptozotocin-induced diabetic rats. Rats were anesthetized with thiobutabarbital, and the left kidney was exposed. Total, cortical, and medullary renal blood flow was investigated before and after renal artery infusion of increasing doses of either l-homoarginine to inhibit cellular uptake of l-arginine or N ω -nitro- l-arginine methyl ester (l-NAME) to inhibit nitric oxide synthase. l-Homoarginine infusion did not affect total or cortical blood flow in any of the groups, but caused a dose-dependent reduction in medullary blood flow. l-NAME decreased total, cortical and medullary blood flow in both groups. However, the reductions in medullary blood flow in response to both l-homoarginine and l-NAME were more pronounced in the control groups compared with the diabetic groups. Isolated cortical tubular cells displayed similar l-arginine uptake capacity whereas medullary tubular cells isolated from diabetic rats had increased l-arginine uptake capacity. Diabetics had reduced l-arginine concentrations in plasma and medullary tissue but increased l-arginine concentration in cortical tissue. In conclusion, the reduced l-arginine availability in plasma and medullary tissue in diabetes results in reduced nitric oxide-mediated regulation of renal medullary hemodynamics. Cortical blood flow regulation displays less dependency on extracellular l-arginine and the upregulated cortical tissue l-arginine may protect cortical hemodynamics in diabetes. Copyright © 2017 the American Physiological Society.

Anti-Obesity Effects of Starter Fermented Kimchi on 3T3-L1 Adipocytes

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Lee, Kyung-Hee; Song, Jia-Le; Park, Eui-Seong; Ju, Jaehyun; Kim, Hee-Young; Park, Kun-Young

2015-01-01

The anti-obesity effects of starter (Leuconostoc mesenteroides+Lactobacillus plantarum) fermented kimchi on 3T3-L1 adipocyte were studied using naturally fermented kimchi (NK), a functional kimchi (FK, NK supplemented with green tea), and FK supplemented with added starters (FKS). Oil red O staining and cellular levels of triglyceride (TG) and glycerol were used to evaluate the in vitro anti-obesity effects of these kimchis in 3T3-L1 cells. The expressions of adipogenesis/lipogenesis-related genes of peroxisome proliferator-active receptor (PPAR)-γ, CCAAT/enhance-binding protein (C/EBP)-α, and fatty acid synthase (FAS) were determined by RT-PCR. Kimchis, especially FKS, markedly decreased TG levels and increased levels of intracellular glycerol and lipid lipolysis. In addition, FKS also reduced the mRNA levels of PPAR-γ, C/EBP-α, and FAS, which are related to adipogenesis/lipogenesis in 3T3-L1 cells. These results suggest the anti-obesity effects of FKS were to due to enhanced lipolysis and reduced adipogenesis/lipogenesis in 3T3-L1 adipocytes. PMID:26770918

Design and evaluation of cellular power converter architectures

Science.gov (United States)

Perreault, David John

Power electronic technology plays an important role in many energy conversion and storage applications, including machine drives, power supplies, frequency changers and UPS systems. Increases in performance and reductions in cost have been achieved through the development of higher performance power semiconductor devices and integrated control devices with increased functionality. Manufacturing techniques, however, have changed little. High power is typically achieved by paralleling multiple die in a sing!e package, producing the physical equivalent of a single large device. Consequently, both the device package and the converter in which the device is used continue to require large, complex mechanical structures, and relatively sophisticated heat transfer systems. An alternative to this approach is the use of a cellular power converter architecture, which is based upon the parallel connection of a large number of quasi-autonomous converters, called cells, each of which is designed for a fraction of the system rating. The cell rating is chosen such that single-die devices in inexpensive packages can be used, and the cell fabricated with an automated assembly process. The use of quasi-autonomous cells means that system performance is not compromised by the failure of a cell. This thesis explores the design of cellular converter architectures with the objective of achieving improvements in performance, reliability, and cost over conventional converter designs. New approaches are developed and experimentally verified for highly distributed control of cellular converters, including methods for ripple cancellation and current-sharing control. The performance of these techniques are quantified, and their dynamics are analyzed. Cell topologies suitable to the cellular architecture are investigated, and their use for systems in the 5-500 kVA range is explored. The design, construction, and experimental evaluation of a 6 kW cellular switched-mode rectifier is also addressed

Lipogenesis from U14C lactate in obese Zucker rat hepatocytes. Effect of albumin-bound oleate

International Nuclear Information System (INIS)

Porquet, D.; Serbource-Goguel, N.; Durand, G.; Maccario, J.; Feger, J.; Agneray, J.

1984-01-01

Lipogenesis from U( 14 C) lactate was studied in hepatocytes isolated from obese Zucker rats (fa/fa) their lean littermates (Fa/.) and Sprague Dawley rats. The distribution of radioactive carbon between the glycerol and the fatty acid moieties of the acylglycerols were studied. Radioactive lactate was better utilized for glycerol formation than it was for fatty acid formation in the obese rats. However, when oleate was added to the hepatocytic incubation medium, radioactive lactate was preferentially incorporated into the fatty acid moiety of the acyglycerols. Among the nutrients, lactate seems to be a better source of carbon than glucose for lipid synthesis. It has been shown that there is increased hepatic portal blood concentration of lactate several hours after eating: about 4 mM in Wistar rats and 10-15 mM in obese Zucher rats. We are interested in determin the incorporation of carbon from lactate either into glycerol or into fatty acid moieties of hepatic acylgylcerols, and in determining the influence of exogenous fatty acids on acylgylcerol synthesis, since a high level of circulating fatty acids in Zucher obese rats has been reported. The purpose was to determine the incorporaton of lactate into glycerol and fatty moieties of acylglycerols, under the influence of oleate

Polyomavirus specific cellular immunity: from BK-virus-specific cellular immunity to BK-virus-associated nephropathy ?

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manon edekeyser

2015-06-01

Full Text Available In renal transplantation, BK-virus-associated nephropathy has emerged as a major complication, with a prevalence of 5–10% and graft loss in >50% of cases. BK-virus is a member of the Polyomavirus family and rarely induces apparent clinical disease in the general population. However, replication of polyomaviruses, associated with significant organ disease, is observed in patients with acquired immunosuppression, which suggests a critical role for virus-specific cellular immunity to control virus replication and prevent chronic disease. Monitoring of specific immunity combined with viral load could be used to individually assess the risk of viral reactivation and virus control. We review the current knowledge on BK-virus specific cellular immunity and, more specifically, in immunocompromised patients. In the future, immune-based therapies could allow us to treat and prevent BK-virus-associated nephropathy.

Sub-cellular distribution and translocation of TRP channels.

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Toro, Carlos A; Arias, Luis A; Brauchi, Sebastian

2011-01-01

Cellular electrical activity is the result of a highly complex processes that involve the activation of ion channel proteins. Ion channels make pores on cell membranes that rapidly transit between conductive and non-conductive states, allowing different ions to flow down their electrochemical gradients across cell membranes. In the case of neuronal cells, ion channel activity orchestrates action potentials traveling through axons, enabling electrical communication between cells in distant parts of the body. Somatic sensation -our ability to feel touch, temperature and noxious stimuli- require ion channels able to sense and respond to our peripheral environment. Sensory integration involves the summing of various environmental cues and their conversion into electrical signals. Members of the Transient Receptor Potential (TRP) family of ion channels have emerged as important mediators of both cellular sensing and sensory integration. The regulation of the spatial and temporal distribution of membrane receptors is recognized as an important mechanism for controlling the magnitude of the cellular response and the time scale on which cellular signaling occurs. Several studies have shown that this mechanism is also used by TRP channels to modulate cellular response and ultimately fulfill their physiological function as sensors. However, the inner-working of this mode of control for TRP channels remains poorly understood. The question of whether TRPs intrinsically regulate their own vesicular trafficking or weather the dynamic regulation of TRP channel residence on the cell surface is caused by extrinsic changes in the rates of vesicle insertion or retrieval remain open. This review will examine the evidence that sub-cellular redistribution of TRP channels plays an important role in regulating their activity and explore the mechanisms that control the trafficking of vesicles containing TRP channels.

Cellularized Bilayer Pullulan-Gelatin Hydrogel for Skin Regeneration.

Science.gov (United States)

Nicholas, Mathew N; Jeschke, Marc G; Amini-Nik, Saeid

2016-05-01

Skin substitutes significantly reduce the morbidity and mortality of patients with burn injuries and chronic wounds. However, current skin substitutes have disadvantages related to high costs and inadequate skin regeneration due to highly inflammatory wounds. Thus, new skin substitutes are needed. By combining two polymers, pullulan, an inexpensive polysaccharide with antioxidant properties, and gelatin, a derivative of collagen with high water absorbency, we created a novel inexpensive hydrogel-named PG-1 for "pullulan-gelatin first generation hydrogel"-suitable for skin substitutes. After incorporating human fibroblasts and keratinocytes onto PG-1 using centrifugation over 5 days, we created a cellularized bilayer skin substitute. Cellularized PG-1 was compared to acellular PG-1 and no hydrogel (control) in vivo in a mouse excisional skin biopsy model using newly developed dome inserts to house the skin substitutes and prevent mouse skin contraction during wound healing. PG-1 had an average pore size of 61.69 μm with an ideal elastic modulus, swelling behavior, and biodegradability for use as a hydrogel for skin substitutes. Excellent skin cell viability, proliferation, differentiation, and morphology were visualized through live/dead assays, 5-bromo-2'-deoxyuridine proliferation assays, and confocal microscopy. Trichrome and immunohistochemical staining of excisional wounds treated with the cellularized skin substitute revealed thicker newly formed skin with a higher proportion of actively proliferating cells and incorporation of human cells compared to acellular PG-1 or control. Excisional wounds treated with acellular or cellularized hydrogels showed significantly less macrophage infiltration and increased angiogenesis 14 days post skin biopsy compared to control. These results show that PG-1 has ideal mechanical characteristics and allows ideal cellular characteristics. In vivo evidence suggests that cellularized PG-1 promotes skin regeneration and may

Production, properties, and applications of hydrocolloid cellular solids.

Science.gov (United States)

Nussinovitch, Amos

2005-02-01

Many common synthetic and edible materials are, in fact, cellular solids. When classifying the structure of cellular solids, a few variables, such as open vs. closed cells, flexible vs. brittle cell walls, cell-size distribution, cell-wall thickness, cell shape, the uniformity of the structure of the cellular solid and the different scales of length are taken into account. Compressive stress-strain relationships of most cellular solids can be easily identified according to their characteristic sigmoid shape, reflecting three deformation mechanisms: (i) elastic distortion under small strains, (ii) collapse and/or fracture of the cell walls, and (iii) densification. Various techniques are used to produce hydrocolloid (gum) cellular solids. The products of these include (i) sponges, obtained when the drying gel contains the occasionally produced gas bubbles; (ii) sponges produced by the immobilization of microorganisms; (iii) solid foams produced by drying foamed solutions or gels containing oils, and (iv) hydrocolloid sponges produced by enzymatic reactions. The porosity of the manufactured cellular solid is subject to change and depends on its composition and the processing technique. The porosity is controlled by a range of methods and the resulting surface structures can be investigated by microscopy and analyzed using fractal methods. Models used to describe stress-strain behaviors of hydrocolloid cellular solids as well as multilayered products and composites are discussed in detail in this manuscript. Hydrocolloid cellular solids have numerous purposes, simple and complex, ranging from dried texturized fruits to carriers of vitamins and other essential micronutrients. They can also be used to control the acoustic response of specific dry food products, and have a great potential for future use in countless different fields, from novel foods and packaging to medicine and medical care, daily commodities, farming and agriculture, and the environmental, chemical

A brominated flame retardant 2,2',4,4' tetrabrominated diphenyl ether (BDE-47) leads to lipogenesis in the copepod Tigriopus japonicus.

Science.gov (United States)

Lee, Min-Chul; Han, Jeonghoon; Lee, Seung-Hwi; Kim, Duck-Hyun; Kang, Hye-Min; Won, Eun-Ji; Hwang, Dae-Sik; Park, Jun Chul; Om, Ae-Son; Lee, Jae-Seong

2016-09-01

De novo lipogenesis (DNL) is a fatty acid synthesis process that requires several genes, including sterol regulatory element binding protein (SREBP), ATP-citrate lyase (ACLY), and acetyl-CoA carboxylase (ACC). DNL up-regulation is able to induce fat accumulation through an increase in fatty acids. To investigate the relationship between DNL up-regulation and the accumulation of fatty acids and lipid droplets in response to 2,2',4,4' tetrabrominated diphenyl ether (BDE-47), we examined DNL in the copepod Tigriopus japonicus. Transcription levels of DNL-related genes were increased after exposure to 2.5μg/L BDE-47 for 24h. After exposure to 2.5μg/L BDE-47, palmitic acid was significantly increased (Pcopepod. This study provides a better understanding of the effects of BDE-47 on DNL in copepods. Copyright © 2016 Elsevier B.V. All rights reserved.

Cell adhesion control by ion implantation into extra-cellular matrix

International Nuclear Information System (INIS)

Suzuki, Yoshiaki; Kusakabe, Masahiro; Kaibara, Makoto; Iwaki, Masaya; Sasabe, Hiroyuki; Nishisaka, Tsuyoshi

1994-01-01

Cell adhesion control of polymer surfaces by ion implantation into polymers and extra-cellular matrix has been studied by means of in vitro adhesion measurements of the carcinoma of the cervix (HeLa cell). The specimens used were polystyrene (PS), oxygen plasma treated polystyrene (PS-O), extra-cellular matrix (Collagen: Type I) coated polystyrene (PS-C), and gelatin coated polystyrene (PS-G). Ne + , Na + , and Ar + implantations were performed with a fluence of 1x10 15 ions/cm 2 at energies of 50, 100 and 150 keV. The chemical and physical structures of ion implanted specimens have been investigated by Fourier transform infrared spectroscopy (FT-IR-ATR), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Ion implanted PS demonstrated a dramatic improvement of adhesion of HeLa cell. HeLa cell adhered only to ion implanted circular domains of a diameter about 0.1 mm on PS. By contrast, ion implanted PS-C, PS-G and PS-O domains inhibited the cell adhesion. These phenomena were observed on Ne + , Na + , and Ar + implanted specimens at energies of 50, 100, and 150 keV. Ion implantation broke the original chemical bonds to form new radicals such as =C=O, condensed rings, C-C, C-O and OH radical. Ion implanted PS had a large amount of new radicals compared with that of PS-C, PS-G and PS-O. Ion implantation broke NH and NH 3 bonds originating from amino acid in PS-C and PS-G. OH and =C=O caused by oxygen treatment in PS-O were also destroyed by ion implantation. It is concluded that cell adhesion to ion implanted PS was caused by carbon structure and new radicals induced by ion implantation. The inhibition of HeLa cell adhesion on PS-C, PS-G and PS-O was caused by the destruction of cell adhesion properties of amino acid, OH and =C=O by radiation effects. ((orig.))

Dihydrotestosterone induces SREBP-1 expression and lipogenesis through the phosphoinositide 3-kinase/Akt pathway in HaCaT cells

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Zhou Bing-rong

2012-11-01

Full Text Available Abstract Background The purpose of this study was to investigate the effects and mechanisms of dihydrotestosterone (DHT-induced expression of sterol regulatory element binding protein-1 (SREBP-1, and the synthesis and secretion of lipids, in HaCaT cells. HaCaT cells were treated with DHT and either the phosphoinositide 3-kinase inhibitor LY294002 or the extracellular-signal-regulated kinase (ERK inhibitor PD98059. Real time-PCR, Western blot, Oil Red staining and flow cytometry were employed to examine the mRNA and protein expressions of SREBP-1, the gene transcription of lipid synthesis, and lipid secretion in HaCaT cells. Findings We found that DHT upregulated mRNA and protein expressions of SREBP-1. DHT also significantly upregulated the transcription of lipid synthesis-related genes and increased lipid secretion, which can be inhibited by the addition of LY294002. Conclusions Collectively, these results indicate that DHT induces SREBP-1 expression and lipogenesis in HaCaT cells via activation of the phosphoinositide 3-kinase/Akt Pathway.

Cellular phone interference with the operation of mechanical ventilators.

Science.gov (United States)

Shaw, Cheryl I; Kacmarek, Robert M; Hampton, Rickey L; Riggi, Vincent; El Masry, Ashraf; Cooper, Jeffrey B; Hurford, William E

2004-04-01

To determine whether a cellular phone would interfere with the operation of mechanical ventilators. Laboratory study. University medical center. Fourteen mechanical ventilators. We evaluated change in operation and malfunction of the mechanical ventilators. The cellular phone (Nokia 6120i) was computer controlled, operating at 828.750 MHz analog modulation. It was operated at 16, 40, 100, 250, and 600 mW, 30 cm from the floor and 30, 15, and ventilator. Six of the 14 ventilators tested malfunctioned when a cellular phone at maximum power output was placed ventilating when the cellular phone at maximum power output was placed ventilator. One ventilator doubled the ventilatory rate and another increased the displayed tidal volume from 350 to 1033 mL. In one of the infant ventilators, displayed tidal volume increased from 21 to 100 mL. In another ventilator, the high respiratory rate alarm sounded but the rate had not changed. In a controlled laboratory setting, cellular phones placed in close proximity to some commercially available intensive care ventilators can cause malfunctions, including irrecoverable cessation of ventilation. This is most likely to occur if the cellular phone is or =3 feet from all medical devices. The current electromagnetic compatibility standards for mechanical ventilators are inadequate to prevent malfunction. Manufacturers should ensure that their products are not affected by wireless technology even when placed immediately next to the device.

The Role of the Multifunctional BAG3 Protein in Cellular Protein Quality Control and in Disease.

Science.gov (United States)

Stürner, Elisabeth; Behl, Christian

2017-01-01

In neurons, but also in all other cells the complex proteostasis network is monitored and tightly regulated by the cellular protein quality control (PQC) system. Beyond folding of newly synthesized polypeptides and their refolding upon misfolding the PQC also manages the disposal of aberrant proteins either by the ubiquitin-proteasome machinery or by the autophagic-lysosomal system. Aggregated proteins are primarily degraded by a process termed selective macroautophagy (or aggrephagy). One such recently discovered selective macroautophagy pathway is mediated by the multifunctional HSP70 co-chaperone BAG3 ( BCL-2-associated athanogene 3 ). Under acute stress and during cellular aging, BAG3 in concert with the molecular chaperones HSP70 and HSPB8 as well as the ubiquitin receptor p62/SQSTM1 specifically targets aggregation-prone proteins to autophagic degradation. Thereby, BAG3-mediated selective macroautophagy represents a pivotal adaptive safeguarding and emergency system of the PQC which is activated under pathophysiological conditions to ensure cellular proteostasis. Interestingly, BAG3-mediated selective macroautophagy is also involved in the clearance of aggregated proteins associated with age-related neurodegenerative disorders, like Alzheimer's disease (tau-protein), Huntington's disease (mutated huntingtin/polyQ proteins), and amyotrophic lateral sclerosis (mutated SOD1). In addition, based on its initial description BAG3 is an anti-apoptotic protein that plays a decisive role in other widespread diseases, including cancer and myopathies. Therefore, in the search for novel therapeutic intervention avenues in neurodegeneration, myopathies and cancer BAG3 is a promising candidate.

[Risk-oriented model of the control of the level of electric magnetic fields of base stations of cellular communications].

Science.gov (United States)

Lutsenko, L A; Tulakin, A V; Egorova, A M; Mikhailova, O M; Gvozdeva, L L; Chigryay, E K

The purpose of this study was to give the description of harmful effects of the impact of electromagnetic radiations from base stations of cellular communication as the most common sources of radio frequencies of electromagnetic fields in the environment. The highest values of the energy flux density were measured on the roofs of houses where antennas are installed - more than 10 pW/cm. The lowest values were recorded in inside premises with expositions of 0.1-1 pW/cm. In the close location of the railway station to the base stations of the cellular communication there was seen a cumulative effect. There are proposed both new safe hygienic approaches to the control for the safety of the work of base station and protective measures.

Coculture with BJ fibroblast cells inhibits the adipogenesis and lipogenesis in 3T3-L1 cells

International Nuclear Information System (INIS)

Jeong, Hyun Jeong; Park, Sahng Wook; Kim, Hojeong; Park, Sang-Kyu; Yoon, Dojun

2010-01-01

Mouse or human fibroblasts are commonly used as feeder cells to prevent differentiation in stem or primary cell culture. In the present study, we addressed whether fibroblasts can affect the differentiation of adipocytes. We found that the differentiation of 3T3-L1 preadipocytes was strongly suppressed when the cells were cocultured with human fibroblast (BJ) cells. BrdU incorporation analysis indicated that mitotic clonal expansion, an early event required for 3T3-L1 cell adipogenesis, was not affected by BJ cells. The 3T3-L1 cell expression levels of peroxisome proliferator-activated receptor γ2, CCAAT/enhancer-binding protein alpha (C/EBPα), sterol regulatory element binding protein-1c, and Krueppel-like factor 15, but not those of C/EBPβ or C/EBPδ, were decreased by coculture with BJ cells. When mature 3T3-L1 adipocytes were cocultured with BJ cells, their lipid contents were significantly reduced, with decreased fatty acid synthase expression and increased phosphorylated form of acetyl-CoA carboxylase 1. Our data indicate that coculture with BJ fibroblast cells inhibits the adipogenesis of 3T3-L1 preadipocytes and decreases the lipogenesis of mature 3T3-L1 adipocytes.

Insulin-like growth factor-I, physical activity, and control of cellular anabolism.

Science.gov (United States)

Nindl, Bradley C

2010-01-01

The underlying mechanisms responsible for mediating the beneficial outcomes of exercise undoubtedly are many, but the insulin-like growth factor-I (IGF-I) system is emerging as an important and central hormonal axis that plays a significant role concerning cellular anabolism. This introductory article summarizes the intent and the content for papers presented as part of a 2008 American College of Sports Medicine national symposium entitled "Insulin-like Growth Factor-I, Physical Activity, and Control of Cellular Anabolism." The individual authors and their papers are as follows: Jan Frystyk authoring "The relationship between exercise and the growth hormone/insulin-like growth factor-I axis," Greg Adams authoring "IGF-I signaling in skeletal muscle and the potential for cytokine interactions," and Brad Nindl authoring "Insulin-like growth factor-I as a biomarker of health, fitness, and training status." These papers focus on 1) different assay methodologies for IGF-I within the paradigm of exercise studies, 2) research demonstrating that intracellular signaling components associated with several proinflammatory cytokines have the potential to interact with anabolic signaling processes in skeletal muscle, and 3) an overview of IGF-I as a biomarker related to exercise training, muscle and bone remodeling, body composition, cognition, and cancer. When summed in total, the contribution that these papers will make will undoubtedly involve bringing attention to the vast regulatory complexity of the IGF-I system and will hopefully convince the reader that the IGF-I system warrants further detailed scientific inquiry to resolve many unanswered questions and paradoxical experimental findings. The IGF-I system remains one of the most intriguing and captivating marvels of human physiology that seems central in mediating numerous adaptations from physical activity.

Iron Oxide Nanoparticles Stimulates Extra-Cellular Matrix Production in Cellular Spheroids

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Megan Casco

2017-01-01

Full Text Available Nanotechnologies have been integrated into drug delivery, and non-invasive imaging applications, into nanostructured scaffolds for the manipulation of cells. The objective of this work was to determine how the physico-chemical properties of magnetic nanoparticles (MNPs and their spatial distribution into cellular spheroids stimulated cells to produce an extracellular matrix (ECM. The MNP concentration (0.03 mg/mL, 0.1 mg/mL and 0.3 mg/mL, type (magnetoferritin, shape (nanorod—85 nm × 425 nm and incorporation method were studied to determine each of their effects on the specific stimulation of four ECM proteins (collagen I, collagen IV, elastin and fibronectin in primary rat aortic smooth muscle cell. Results demonstrated that as MNP concentration increased there was up to a 6.32-fold increase in collagen production over no MNP samples. Semi-quantitative Immunohistochemistry (IHC results demonstrated that MNP type had the greatest influence on elastin production with a 56.28% positive area stain compared to controls and MNP shape favored elastin stimulation with a 50.19% positive area stain. Finally, there are no adverse effects of MNPs on cellular contractile ability. This study provides insight on the stimulation of ECM production in cells and tissues, which is important because it plays a critical role in regulating cellular functions.

Cellular Automata Simulation for Wealth Distribution

Science.gov (United States)

Lo, Shih-Ching

2009-08-01

Wealth distribution of a country is a complicate system. A model, which is based on the Epstein & Axtell's "Sugars cape" model, is presented in Netlogo. The model considers the income, age, working opportunity and salary as control variables. There are still other variables should be considered while an artificial society is established. In this study, a more complicate cellular automata model for wealth distribution model is proposed. The effects of social welfare, tax, economical investment and inheritance are considered and simulated. According to the cellular automata simulation for wealth distribution, we will have a deep insight of financial policy of the government.

Hydrogen peroxide probes directed to different cellular compartments.

OpenAIRE

Mikalai Malinouski; You Zhou; Vsevolod V Belousov; Dolph L Hatfield; Vadim N Gladyshev

2011-01-01

Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular ...

Modeling of coupled differential equations for cellular chemical signaling pathways: Implications for assay protocols utilized in cellular engineering.

Science.gov (United States)

O'Clock, George D

2016-08-01

Cellular engineering involves modification and control of cell properties, and requires an understanding of fundamentals and mechanisms of action for cellular derived product development. One of the keys to success in cellular engineering involves the quality and validity of results obtained from cell chemical signaling pathway assays. The accuracy of the assay data cannot be verified or assured if the effect of positive feedback, nonlinearities, and interrelationships between cell chemical signaling pathway elements are not understood, modeled, and simulated. Nonlinearities and positive feedback in the cell chemical signaling pathway can produce significant aberrations in assay data collection. Simulating the pathway can reveal potential instability problems that will affect assay results. A simulation, using an electrical analog for the coupled differential equations representing each segment of the pathway, provides an excellent tool for assay validation purposes. With this approach, voltages represent pathway enzyme concentrations and operational amplifier feedback resistance and input resistance values determine pathway gain and rate constants. The understanding provided by pathway modeling and simulation is strategically important in order to establish experimental controls for assay protocol structure, time frames specified between assays, and assay concentration variation limits; to ensure accuracy and reproducibility of results.

Multi-cellular logistics of collective cell migration.

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Masataka Yamao

Full Text Available During development, the formation of biological networks (such as organs and neuronal networks is controlled by multicellular transportation phenomena based on cell migration. In multi-cellular systems, cellular locomotion is restricted by physical interactions with other cells in a crowded space, similar to passengers pushing others out of their way on a packed train. The motion of individual cells is intrinsically stochastic and may be viewed as a type of random walk. However, this walk takes place in a noisy environment because the cell interacts with its randomly moving neighbors. Despite this randomness and complexity, development is highly orchestrated and precisely regulated, following genetic (and even epigenetic blueprints. Although individual cell migration has long been studied, the manner in which stochasticity affects multi-cellular transportation within the precisely controlled process of development remains largely unknown. To explore the general principles underlying multicellular migration, we focus on the migration of neural crest cells, which migrate collectively and form streams. We introduce a mechanical model of multi-cellular migration. Simulations based on the model show that the migration mode depends on the relative strengths of the noise from migratory and non-migratory cells. Strong noise from migratory cells and weak noise from surrounding cells causes "collective migration," whereas strong noise from non-migratory cells causes "dispersive migration." Moreover, our theoretical analyses reveal that migratory cells attract each other over long distances, even without direct mechanical contacts. This effective interaction depends on the stochasticity of the migratory and non-migratory cells. On the basis of these findings, we propose that stochastic behavior at the single-cell level works effectively and precisely to achieve collective migration in multi-cellular systems.

Prolactin suppresses malonyl-CoA concentration in human adipose tissue

DEFF Research Database (Denmark)

Nilsson, L. A.; Roepstorff, Carsten; Kiens, Bente

2009-01-01

Prolactin is best known for its involvement in lactation, where it regulates mechanisms that supply nutrients for milk production. In individuals with pathological hyperprolactinemia, glucose and fat homeostasis have been reported to be negatively influenced. It is not previously known, however......, whether prolactin regulates lipogenesis in human adipose tissue. The aim of this study was to investigate the effect of prolactin on lipogenesis in human adipose tissue in vitro. Prolactin decreased the concentration of malonyl-CoA, the product of the first committed step in lipogenesis, to 77......+/-6% compared to control 100+/-5% (p=0.022) in cultured human adipose tissue. In addition, prolactin was found to decrease glucose transporter 4 ( GLUT4) mRNA expression, which may cause decreased glucose uptake. In conclusion, we propose that prolactin decreases lipogenesis in human adipose tissue...

Magnetogenetics: Remote Control of Cellular Signaling with Magnetic Fields

Science.gov (United States)

Sauer, Jeremy P.

Means for temporally regulating gene expression and cellular activity are invaluable for elucidating the underlying physiological processes and have therapeutic implications. Here we report the development of a system for remote regulation of gene expression by low frequency radiowaves (RF) or by a static magnetic field. We accomplished this by first adding iron oxide nanoparticles - either exogenously or as genetically encoded ferritin/ferric oxyhydroxide particle. These particles have been designed with affinity to the plasma membrane ion channel Transient Receptor Potential Vanilloid 1 (TRPV1) by a conjugated antibody. Application of a magnetic field stimulates the particle to gate the ion channel and this, in turn, initiates calcium-dependent transgene expression. We first demonstrated in vitro that TRPV1 can be actuated to cause calcium flux into the cell by directly applying a localized magnetic field. In mice expressing these genetically encoded components, application of external magnetic field caused remote stimulation of insulin transgene expression and significantly lowered blood glucose. In addition, we are investigating mechanisms by which iron oxide nanoparticles can absorb RF, and transduce this energy to cause channel opening. This robust, repeatable method for remote cellular regulation in vivo may ultimately have applications in basic science, as well as in technology and therapeutics.

The Role of the Multifunctional BAG3 Protein in Cellular Protein Quality Control and in Disease

Directory of Open Access Journals (Sweden)

Elisabeth Stürner

2017-06-01

Full Text Available In neurons, but also in all other cells the complex proteostasis network is monitored and tightly regulated by the cellular protein quality control (PQC system. Beyond folding of newly synthesized polypeptides and their refolding upon misfolding the PQC also manages the disposal of aberrant proteins either by the ubiquitin-proteasome machinery or by the autophagic-lysosomal system. Aggregated proteins are primarily degraded by a process termed selective macroautophagy (or aggrephagy. One such recently discovered selective macroautophagy pathway is mediated by the multifunctional HSP70 co-chaperone BAG3 (BCL-2-associated athanogene 3. Under acute stress and during cellular aging, BAG3 in concert with the molecular chaperones HSP70 and HSPB8 as well as the ubiquitin receptor p62/SQSTM1 specifically targets aggregation-prone proteins to autophagic degradation. Thereby, BAG3-mediated selective macroautophagy represents a pivotal adaptive safeguarding and emergency system of the PQC which is activated under pathophysiological conditions to ensure cellular proteostasis. Interestingly, BAG3-mediated selective macroautophagy is also involved in the clearance of aggregated proteins associated with age-related neurodegenerative disorders, like Alzheimer’s disease (tau-protein, Huntington’s disease (mutated huntingtin/polyQ proteins, and amyotrophic lateral sclerosis (mutated SOD1. In addition, based on its initial description BAG3 is an anti-apoptotic protein that plays a decisive role in other widespread diseases, including cancer and myopathies. Therefore, in the search for novel therapeutic intervention avenues in neurodegeneration, myopathies and cancer BAG3 is a promising candidate.

Effect of α-linolenic acid and DHA intake on lipogenesis and gene expression involved in fatty acid metabolism in growing-finishing pigs.

Science.gov (United States)

De Tonnac, A; Labussière, E; Vincent, A; Mourot, J

2016-07-01

The regulation of lipogenesis mechanisms related to consumption of n-3 PUFA is poorly understood. The aim of the present study was to find out whether α-linolenic acid (ALA) or DHA uptake can have an effect on activities and gene expressions of enzymes involved in lipid metabolism in the liver, subcutaneous adipose tissue and longissimus dorsi (LD) muscle of growing-finishing pigs. Six groups of ten pigs received one of six experimental diets supplemented with rapeseed oil in the control diet, extruded linseed, microalgae or a mixture of both to implement different levels of ALA and DHA with the same content in total n-3. Results were analysed for linear and quadratic effects of DHA intake. The results showed that activities of malic enzyme (ME) and fatty acid synthase (FAS) decreased linearly in the liver with dietary DHA. Although the expression of the genes of these enzymes and their activities were poorly correlated, ME and FAS expressions also decreased linearly with DHA intake. The intake of DHA down-regulates the expressions of other genes involved in fatty acid (FA) metabolism in some tissues of pigs, such as fatty acid desaturase 2 and sterol-regulatory element binding transcription factor 1 in the liver and 2,4-dienoyl CoA reductase 2 in the LD muscle. FA oxidation in the LD muscle and FA synthesis decreased in the liver with increasing amount of dietary DHA, whereas a retroconversion of DHA into EPA seems to be set up in this last tissue.

[Control of asthma symptoms and cellular markers of inflammation in induced sputum in children and adolescents with chronic asthma].

Science.gov (United States)

Ciółkowski, Janusz; Stasiowska, Barbara; Mazurek, Henryk

2009-03-01

After the GINA 2006 publication, asthma therapy is based on control of symptoms. However there are suggestions of monitoring of airway inflammation. Aim of the study was to compare clinical criteria of asthma control with cellular markers of lower airway inflammation in induced sputum in a group of young asthmatics. To assess relationship between sputum eosinophilia, asthma severity and spirometry. A group of 154 young patients with chronic asthma (8-21 years) underwent sputum induction by inhalation of 4,5% saline solution. Sputum induction was effective in 121 patients (78%), and in this group control of clinical symptoms was assessed according to GINA 2006 criteria. Asthma was controlled in 82 subjects (67.8%) and uncontrolled in 39 (32.2%). Patients with controlled asthma had higher FEV1/FVC (79.8 +/- 7.1% vs 74.2 +/- 9.9%; p = 0.004) and MMEF (80.7 +/- 23.0% vs 65.3 +/- 21.8%; p 3%) was observed in 24.4% of patients with controlled asthma and in 61.5% with uncontrolled asthma (p astma than in patients with moderate-severe disease (3.1 +/- 5.7% vs 7.1% +/- 8.8; p = 0.006). Patients with high sputum eosinophil count had lower FEV1 (89.4 +/- 14.9% vs 94.9 +/- 13.9%; p = 0.047), FEV1/FVC (74.5 +/- 10.1% vs 79.2 +/- 9.3%; p = 0.01) and MMEF (68.7 +/- 23.3% vs 81.7 +/- 23.1%; p = 0.004). In this study of young asthmatics, control of asthma symptoms was observed in 67.8% of patients. However, cellular markers of lower airway inflammation were present in 1/4 of patients with controlled asthma and in 3/4 with uncontrolled disease. Sputum eosinophilia was related to asthma severity. FEV1/FVC and MMEF were more important that FEV1 for estimating control of asthma. Improvement of asthma control scoring is needed as well as availability of simple methods of inflammation monitoring.

Reduced labor and condensed schedules with cellular concrete solutions

Energy Technology Data Exchange (ETDEWEB)

Lavis, D. [CEMATRIX Inc., Calgary, AB (Canada)

2008-07-01

This paper discussed the use of cellular concrete materials in oil sands tank base foundation systems, shallow buried utility insulation systems, roadways, slabs, and buried modules. The concrete is formed from Portland cement, water, specialized pre-formed foaming agents, and air mixed in controlled proportions. Fly ash and polypropylene or glass fibers can also be used as additions. Cellular concrete can often be used to speed up construction and minimize labour requirements. Cellular concrete can be cast-in-place, and has soil-stabilizing and self-compacting features. The concrete can be produced and placed on-site at rates exceeding 120 cubic meters per hour. Cellular concrete can be pumped into place over long distances through flexible hoses. A case study comparing the cellular concrete to traditional plastic foam insulation was used to demonstrate the equivalency and adequacy of insulation, structural properties and installation costs. The study showed that although the cellular concrete had a high installation cost, greater compressive strength was gained. The concrete was self-levelling and did not require compaction or vibration. The use of the cellular concrete resulted in an accelerated construction schedule. 6 refs., 2 tabs., 6 figs.

A rich medium-chain triacylglycerol diet benefits adiposity but has adverse effects on the markers of hepatic lipogenesis and beta-oxidation.

Science.gov (United States)

Chamma, Carolina Maria de Oliveira; Bargut, Thereza Cristina Lonzetti; Mandarim-de-Lacerda, Carlos Alberto; Aguila, Marcia Barbosa

2017-02-22

We investigated the increasing amounts of medium-chain triacylglycerol (MCT) in the diet on hepatic lipid metabolism. Mature C57BL/6 male mice were randomly divided into five groups (n = 10/group). The animals received their diet for 12 weeks, as a control (C group, 10% of energy from lipids); high-fat lard (HF group, isoenergetic diet, 50% of energy from lipids with lard); a mixture of lard and MCT oil (with a gradual replacement of lard by MCT: HF-MCT25%, HF-MCT75%, and HF-MCT100% groups). At euthanasia, we collected blood and dissected the liver for analyses (glucose, insulin, HOMA-IR, QUICK index, and triacylglycerol, light microscopy, western blotting, and RT-qPCR). The HF diet groups showed a greater body mass gain compared to the C group, but the HF-MCT100% group showed diminished adiposity and amelioration of insulin resistance. All the HF groups also showed a clear increase in hepatic lipid accumulation, increased lipogenesis and decreased PPAR-alpha expression, although HF-MCT groups showed improved local insulin signaling. Lastly, the HF-MCT100% group had raised markers of beta-oxidation (UCP3 and MCAD) and mitochondrial biogenesis (PGC1-alpha and NRF1). In conclusion, the findings demonstrated that a high amount of MCT (HF-MCT100% group) added to an HF diet reduces the body fat accumulation and insulin resistance. However, the lipid accumulation as well as the lipid metabolism is altered in the liver of animals fed with a very high MCT diet, indicating that higher doses of MCT may be harmful in a long-term.

Agent-Based Modeling of Mitochondria Links Sub-Cellular Dynamics to Cellular Homeostasis and Heterogeneity.

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Giovanni Dalmasso

Full Text Available Mitochondria are semi-autonomous organelles that supply energy for cellular biochemistry through oxidative phosphorylation. Within a cell, hundreds of mobile mitochondria undergo fusion and fission events to form a dynamic network. These morphological and mobility dynamics are essential for maintaining mitochondrial functional homeostasis, and alterations both impact and reflect cellular stress states. Mitochondrial homeostasis is further dependent on production (biogenesis and the removal of damaged mitochondria by selective autophagy (mitophagy. While mitochondrial function, dynamics, biogenesis and mitophagy are highly-integrated processes, it is not fully understood how systemic control in the cell is established to maintain homeostasis, or respond to bioenergetic demands. Here we used agent-based modeling (ABM to integrate molecular and imaging knowledge sets, and simulate population dynamics of mitochondria and their response to environmental energy demand. Using high-dimensional parameter searches we integrated experimentally-measured rates of mitochondrial biogenesis and mitophagy, and using sensitivity analysis we identified parameter influences on population homeostasis. By studying the dynamics of cellular subpopulations with distinct mitochondrial masses, our approach uncovered system properties of mitochondrial populations: (1 mitochondrial fusion and fission activities rapidly establish mitochondrial sub-population homeostasis, and total cellular levels of mitochondria alter fusion and fission activities and subpopulation distributions; (2 restricting the directionality of mitochondrial mobility does not alter morphology subpopulation distributions, but increases network transmission dynamics; and (3 maintaining mitochondrial mass homeostasis and responding to bioenergetic stress requires the integration of mitochondrial dynamics with the cellular bioenergetic state. Finally, (4 our model suggests sources of, and stress conditions

Are cellular phone blocking applications effective for novice teen drivers?

Science.gov (United States)

Creaser, Janet I; Edwards, Christopher J; Morris, Nichole L; Donath, Max

2015-09-01

Distracted driving is a significant concern for novice teen drivers. Although cellular phone bans are applied in many jurisdictions to restrict cellular phone use, teen drivers often report making calls and texts while driving. The Minnesota Teen Driver Study incorporated cellular phone blocking functions via a software application for 182 novice teen drivers in two treatment conditions. The first condition included 92 teens who ran a driver support application on a smartphone that also blocked phone usage. The second condition included 90 teens who ran the same application with phone blocking but which also reported back to parents about monitored risky behaviors (e.g., speeding). A third control group consisting of 92 novice teen drivers had the application and phone-based software installed on the phones to record cellular phone (but not block it) use while driving. The two treatment groups made significantly fewer calls and texts per mile driven compared to the control group. The control group data also demonstrated a higher propensity to text while driving rather than making calls. Software that blocks cellular phone use (except 911) while driving can be effective at mitigating calling and texting for novice teen drivers. However, subjective data indicates that some teens were motivated to find ways around the software, as well as to use another teen's phone while driving when they were unable to use theirs. Cellular phone bans for calling and texting are the first step to changing behaviors associated with texting and driving, particularly among novice teen drivers. Blocking software has the additional potential to reduce impulsive calling and texting while driving among novice teen drivers who might logically know the risks, but for whom it is difficult to ignore calling or texting while driving. Copyright © 2015 Elsevier Ltd and National Safety Council. All rights reserved.

Cell cycle regulation of the BRCA1/acetyl-CoA-carboxylase complex.

Science.gov (United States)

Ray, H; Suau, F; Vincent, A; Dalla Venezia, N

2009-01-16

Germ-line alterations in BRCA1 are associated with an increased susceptibility to breast and ovarian cancer. The BRCA1 protein has been implicated in multiple cellular functions. We have recently demonstrated that BRCA1 reduces acetyl-CoA-carboxylase alpha (ACCA) activity through its phospho-dependent binding to ACCA, and further established that the phosphorylation of the Ser1263 of ACCA is required for this interaction. Here, to gain more insight into the cellular conditions that trigger the BRCA1/ACCA interaction, we designed an anti-pSer1263 antibody and demonstrated that the Ser1263 of ACCA is phosphorylated in vivo, in a cell cycle-dependent manner. We further showed that the interaction between BRCA1 and ACCA is regulated during cell cycle progression. Taken together, our findings reveal a novel mechanism of regulation of ACCA distinct from the previously described phosphorylation of Ser79, and provide new insights into the control of lipogenesis through the cell cycle.

Kefir improves fatty liver syndrome by inhibiting the lipogenesis pathway in leptin-deficient ob/ob knockout mice.

Science.gov (United States)

Chen, H-L; Tung, Y-T; Tsai, C-L; Lai, C-W; Lai, Z-L; Tsai, H-C; Lin, Y-L; Wang, C-H; Chen, C-M

2014-09-01

Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (Pkefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (Pkefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.

Cellular response after irradiation: Cell cycle control and apoptosis

International Nuclear Information System (INIS)

Siles, E.; Valenzuela, M.T.; Nunez, M.I.; Guerrero, R.; Villalobos, M.; Ruiz de Almodovar, J.M.

1997-01-01

The importance of apoptotic death was assessed in a set of experiments, involving eight human tumour cell lines (breast cancer, bladder carcinoma, medulloblastoma). Various aspects of the quantitative study of apoptosis and methods based on the detection of DNA fragmentation (in situ tailing and comet assay) are described and discussed. Data obtained support the hypothesis that apoptosis is not crucial for cellular radiosensitivity and that the relationship between p53 functionality or clonogenic survival and apoptosis may bee cell type specific. (author)

Spatiotemporal control over molecular delivery and cellular encapsulation from electropolymerized micro- and nanopatterned surfaces.

Science.gov (United States)

Stern, Eric; Jay, Steven M; Demento, Stacey L; Murelli, Ryan P; Reed, Mark A; Malinski, Tadeusz; Spiegel, David A; Mooney, David J; Fahmy, Tarek M

2009-07-13

Bioactive, patterned micro- and nanoscale surfaces that can be spatially engineered for three-dimensional ligand presentation and sustained release of signaling molecules represent a critical advance for the development of next-generation diagnostic and therapeutic devices. Lithography is ideally suited to patterning such surfaces due to its precise, easily scalable, high-throughput nature; however, to date polymers patterned by these techniques have not demonstrated the capacity for sustained release of bioactive agents. We demonstrate here a class of lithographically-defined, electropolymerized polymers with monodisperse micro- and nanopatterned features capable of sustained release of bioactive drugs and proteins. We show that precise control can be achieved over the loading capacity and release rates of encapsulated agents and illustrate this aspect using a fabricated surface releasing a model antigen (ovalbumin) and a cytokine (interleukin-2) for induction of a specific immune response. We further demonstrate the ability of this technique to enable three-dimensional control over cellular encapsulation. The efficacy of the described approach is buttressed by its simplicity, versatility, and reproducibility, rendering it ideally suited for biomaterials engineering.

Engineering Cellular Metabolism

DEFF Research Database (Denmark)

Nielsen, Jens; Keasling, Jay

2016-01-01

Metabolic engineering is the science of rewiring the metabolism of cells to enhance production of native metabolites or to endow cells with the ability to produce new products. The potential applications of such efforts are wide ranging, including the generation of fuels, chemicals, foods, feeds...... of metabolic engineering and will discuss how new technologies can enable metabolic engineering to be scaled up to the industrial level, either by cutting off the lines of control for endogenous metabolism or by infiltrating the system with disruptive, heterologous pathways that overcome cellular regulation....

Traffic Accident Propagation Properties and Control Measures for Urban Links Based on Cellular Automata

Directory of Open Access Journals (Sweden)

Xian-sheng Li

2013-01-01

Full Text Available With the rapid development of urban transport and the sharp increase in vehicle population, traffic accidents form one of the most important causes of urban traffic congestion other than the imbalance between traffic supply and demand. Traffic congestion causes severe problems, such as environment contamination and energy dissipation. Therefore, it would be useful to analyze the congestion propagation characteristics after traffic accidents. Numerical analysis and computer simulation were two of the typical methods used at present to study the traffic congestion propagation properties. The latter was more widespread as it is more consistent with the actual traffic flow and more visual than the former. In this paper, an improved cellular automata (CA model was presented to analyze traffic congestion propagation properties and to evaluate control strategies. In order to apply them to urban traffic flow simulation, the CA models have been improved and expanded on. Computer simulations were built for congestion not only extending to the upstream intersection, but also the upstream intersection and the entire road network, respectively. Congestion propagation characteristics after road traffic accidents were obtained, and controls of different severities and durations were analyzed. The results provide the theoretical foundation and practical means for the control of congestion.

Pathway towards Programmable Wave Anisotropy in Cellular Metamaterials

Science.gov (United States)

Celli, Paolo; Zhang, Weiting; Gonella, Stefano

2018-01-01

In this work, we provide a proof-of-concept experimental demonstration of the wave-control capabilities of cellular metamaterials endowed with populations of tunable electromechanical resonators. Each independently tunable resonator comprises a piezoelectric patch and a resistor-inductor shunt, and its resonant frequency can be seamlessly reprogrammed without interfering with the cellular structure's default properties. We show that, by strategically placing the resonators in the lattice domain and by deliberately activating only selected subsets of them, chosen to conform to the directional features of the beamed wave response, it is possible to override the inherent wave anisotropy of the cellular medium. The outcome is the establishment of tunable spatial patterns of energy distillation resulting in a nonsymmetric correction of the wave fields.

Cellular strategies to cope with protein aggregation

NARCIS (Netherlands)

Scior, Annika; Juenemann, Katrin; Kirstein, Janine

2016-01-01

Nature has evolved several mechanisms to detoxify intracellular protein aggregates that arise upon proteotoxic challenges. These include the controlled deposition of misfolded proteins at distinct cellular sites, the protein disaggregation and refolding by molecular chaperones and/or degradation of

Study Design for a Case Control Investigation of Cellular Telephones and Other Risk Factors for Brain Tumors in Adults

International Nuclear Information System (INIS)

Inskip, P.D.; Hatch, E.E.; Stewart, P.A.; Heineman, E.F.; Ziegler, R.G.; Dosemeci, M.; Parry, D.; Rothman, N.; Boice, J.D. Jr.; Wilcosky, T.C.; Watson, D.J.; Shapiro, W.R.; Selker, R.G.; Fine, H.A.; Black, P. McL.; Loeffler, J.S.; Linet, M.S.

1999-01-01

The aetiology of brain tumours is poorly understood. Due, in part, to public concern about a postulated relationship between the use of cellular telephones or other increasingly prevalent environmental exposures and the incidence of brain cancer in adults, the National Cancer Institute is collaborating with three US hospitals in a comprehensive case control study of malignant and benign brain tumours. Factors under consideration include use of cellular phones and other wireless communication devices, workplace exposures to chemical agents and electromagnetic fields, dietary factors, family history of tumours, genetic determinants of susceptibility, home appliance use, reproductive history and hormonal exposures, viruses, medical and dental exposure to ionising radiation, and other aspects of medical history. Approximately 800 newly diagnosed brain tumour cases and 800 controls were enrolled at hospitals in Boston, Phoenix and Pittsburgh from 1994 to 1998. Cases include all adults (age ≥ 18 y) newly diagnosed with a histologically confirmed intracranial glioma, histologically confirmed intracranial meningioma or acoustic neuroma. Controls are patients admitted to the same hospitals as the cases, and treated for any of a variety of non-malignant conditions. Key features of the study include its large size, the emphasis on rapid ascertainment of incident cases and interview of study subjects rather than surrogate respondents, the use of detailed, job-specific questions developed by industrial hygienists to ascertain occupational exposures, and the storage of blood samples for future evaluation of inherited susceptibility, biomarkers of exposure and gene environment interactions. (author)

Movies of cellular and sub-cellular motion by digital holographic microscopy

Directory of Open Access Journals (Sweden)

Yu Lingfeng

2006-03-01

Full Text Available Abstract Background Many biological specimens, such as living cells and their intracellular components, often exhibit very little amplitude contrast, making it difficult for conventional bright field microscopes to distinguish them from their surroundings. To overcome this problem phase contrast techniques such as Zernike, Normarsky and dark-field microscopies have been developed to improve specimen visibility without chemically or physically altering them by the process of staining. These techniques have proven to be invaluable tools for studying living cells and furthering scientific understanding of fundamental cellular processes such as mitosis. However a drawback of these techniques is that direct quantitative phase imaging is not possible. Quantitative phase imaging is important because it enables determination of either the refractive index or optical thickness variations from the measured optical path length with sub-wavelength accuracy. Digital holography is an emergent phase contrast technique that offers an excellent approach in obtaining both qualitative and quantitative phase information from the hologram. A CCD camera is used to record a hologram onto a computer and numerical methods are subsequently applied to reconstruct the hologram to enable direct access to both phase and amplitude information. Another attractive feature of digital holography is the ability to focus on multiple focal planes from a single hologram, emulating the focusing control of a conventional microscope. Methods A modified Mach-Zender off-axis setup in transmission is used to record and reconstruct a number of holographic amplitude and phase images of cellular and sub-cellular features. Results Both cellular and sub-cellular features are imaged with sub-micron, diffraction-limited resolution. Movies of holographic amplitude and phase images of living microbes and cells are created from a series of holograms and reconstructed with numerically adjustable

Cellular gravity

NARCIS (Netherlands)

F.C. Gruau; J.T. Tromp (John)

1999-01-01

textabstractWe consider the problem of establishing gravity in cellular automata. In particular, when cellular automata states can be partitioned into empty, particle, and wall types, with the latter enclosing rectangular areas, we desire rules that will make the particles fall down and pile up on

Hydrogen Peroxide Probes Directed to Different Cellular Compartments

Science.gov (United States)

Malinouski, Mikalai; Zhou, You; Belousov, Vsevolod V.; Hatfield, Dolph L.; Gladyshev, Vadim N.

2011-01-01

Background Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells. Principal Findings Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events. Conclusions We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells. PMID:21283738

Hydrogen peroxide probes directed to different cellular compartments.

Directory of Open Access Journals (Sweden)

Mikalai Malinouski

2011-01-01

Full Text Available Controlled generation and removal of hydrogen peroxide play important roles in cellular redox homeostasis and signaling. We used a hydrogen peroxide biosensor HyPer, targeted to different compartments, to examine these processes in mammalian cells.Reversible responses were observed to various redox perturbations and signaling events. HyPer expressed in HEK 293 cells was found to sense low micromolar levels of hydrogen peroxide. When targeted to various cellular compartments, HyPer occurred in the reduced state in the nucleus, cytosol, peroxisomes, mitochondrial intermembrane space and mitochondrial matrix, but low levels of the oxidized form of the biosensor were also observed in each of these compartments, consistent with a low peroxide tone in mammalian cells. In contrast, HyPer was mostly oxidized in the endoplasmic reticulum. Using this system, we characterized control of hydrogen peroxide in various cell systems, such as cells deficient in thioredoxin reductase, sulfhydryl oxidases or subjected to selenium deficiency. Generation of hydrogen peroxide could also be monitored in various compartments following signaling events.We found that HyPer can be used as a valuable tool to monitor hydrogen peroxide generated in different cellular compartments. The data also show that hydrogen peroxide generated in one compartment could translocate to other compartments. Our data provide information on compartmentalization, dynamics and homeostatic control of hydrogen peroxide in mammalian cells.

The Expression of Can and Camk is Associated with Lipogenesis in the Muscle of Chicken

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Y Yang

2015-09-01

Full Text Available ABSTRACTIntramuscular fat (IMF content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineurin (CaN and Ca2+/calmodulin-dependent protein kinase (CaMK in lipogenesis in chicken muscle. Chickens were slaughtered and sampled at 4, 8, and 16 weeks of age. IMF content and the expression of CaN subunits and CaMK isoforms were measured in the thigh muscle tissue. The results showed that the IMF contents were greater at 16 weeks compared with those at 4 and 8 weeks (p<0.05. Transcription of fatty acid synthase (FAS and fatty acid translocase CD36 (FAT/CD36 mRNA significantly increased with age, from four to 16 weeks (p<0.05. The mRNA levels of CaNB and CaMK IV were significantly lower at 16 weeks than at four weeks (p<0.05, but CaMK II mRNA levels were significantly higher than at four weeks (p<0.05. In order to evaluate the role of CaMK and CaN in adipogenesis, SV cells were incubated in standard adipogenic medium for 24 h and treated with specific inhibitor of CaMK and CaN. The expressions of CCAAT/enhancer binding protein b (C/EBPb, sterol regulatory element-binding protein 1 (SREBP1,and peroxisome proliferation-activated receptor g (PPARγwere dramatically enhanced by the CsA, CaN inhibitor (p<0.05. KN93, CaMK II inhibitor, dramatically repressed the expression of those lipogenic gene (p<0.05. These results indicated that CaN and CaMK had different effects on adipogenesis in the muscle of chickens.

Euterpe oleracea Mart.-Derived Polyphenols Protect Mice from Diet-Induced Obesity and Fatty Liver by Regulating Hepatic Lipogenesis and Cholesterol Excretion.

Science.gov (United States)

de Oliveira, Paola Raquel B; da Costa, Cristiane A; de Bem, Graziele F; Cordeiro, Viviane S C; Santos, Izabelle B; de Carvalho, Lenize C R M; da Conceição, Ellen Paula S; Lisboa, Patrícia Cristina; Ognibene, Dayane T; Sousa, Pergentino José C; Martins, Gabriel R; da Silva, Antônio Jorge R; de Moura, Roberto S; Resende, Angela C

2015-01-01

The aim of this study was to investigate the effect of a polyphenol-rich Açaí seed extract (ASE, 300 mg/kg-1d-1) on adiposity and hepatic steatosis in mice that were fed a high-fat (HF) diet and its underlying mechanisms based on hepatic lipid metabolism and oxidative stress. Four groups were studied: C57BL/6 mice that were fed with standard diet (10% fat, Control), 10% fat + ASE (ASE), 60% fat (HF), and 60% fat + ASE (HF + ASE) for 12 weeks. We evaluated the food intake, body weight gain, serum glucose and lipid profile, hepatic cholesterol and triacyglycerol (TG), hepatic expression of pAMPK, lipogenic proteins (SREBP-1c, pACC, ACC, HMG-CoA reductase) and cholesterol excretion transporters, ABCG5 and ABCG8. We also evaluated the steatosis in liver sections and oxidative stress. ASE reduced body weight gain, food intake, glucose levels, accumulation of cholesterol and TG in the liver, which was associated with a reduction of hepatic steatosis. The increased expressions of SREBP-1c and HMG-CoA reductase and reduced expressions of pAMPK and pACC/ACC in HF group were antagonized by ASE. The ABCG5 and ABCG8 transporters expressions were increased by the extract. The antioxidant effect of ASE was demonstrated in liver of HF mice by restoration of SOD, CAT and GPx activities and reduction of the increased levels of malondialdehyde and protein carbonylation. In conclusion, ASE substantially reduced the obesity and hepatic steatosis induced by HF diet by reducing lipogenesis, increasing cholesterol excretion and improving oxidative stress in the liver, providing a nutritional resource for prevention of obesity-related adiposity and hepatic steatosis.

Controlling cellular P-TEFb activity by the HIV-1 transcriptional transactivator Tat.

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Lisa Muniz

Full Text Available The human immunodeficiency virus 1 (HIV-1 transcriptional transactivator (Tat is essential for synthesis of full-length transcripts from the integrated viral genome by RNA polymerase II (Pol II. Tat recruits the host positive transcription elongation factor b (P-TEFb to the HIV-1 promoter through binding to the transactivator RNA (TAR at the 5'-end of the nascent HIV transcript. P-TEFb is a general Pol II transcription factor; its cellular activity is controlled by the 7SK small nuclear RNA (snRNA and the HEXIM1 protein, which sequester P-TEFb into transcriptionally inactive 7SK/HEXIM/P-TEFb snRNP. Besides targeting P-TEFb to HIV transcription, Tat also increases the nuclear level of active P-TEFb through promoting its dissociation from the 7SK/HEXIM/P-TEFb RNP by an unclear mechanism. In this study, by using in vitro and in vivo RNA-protein binding assays, we demonstrate that HIV-1 Tat binds with high specificity and efficiency to an evolutionarily highly conserved stem-bulge-stem motif of the 5'-hairpin of human 7SK snRNA. The newly discovered Tat-binding motif of 7SK is structurally and functionally indistinguishable from the extensively characterized Tat-binding site of HIV TAR and importantly, it is imbedded in the HEXIM-binding elements of 7SK snRNA. We show that Tat efficiently replaces HEXIM1 on the 7SK snRNA in vivo and therefore, it promotes the disassembly of the 7SK/HEXIM/P-TEFb negative transcriptional regulatory snRNP to augment the nuclear level of active P-TEFb. This is the first demonstration that HIV-1 specifically targets an important cellular regulatory RNA, most probably to promote viral transcription and replication. Demonstration that the human 7SK snRNA carries a TAR RNA-like Tat-binding element that is essential for the normal transcriptional regulatory function of 7SK questions the viability of HIV therapeutic approaches based on small drugs blocking the Tat-binding site of HIV TAR.

Cellular adverse actions of dibromoacetonitrile, a by-product in water bacterial control, at sublethal levels in rat thymocytes.

Science.gov (United States)

Kishida, Takumi; Akiyoshi, Kenji; Erdenedalai, Erdenebat; Enhetomuru, Anu; Imai, Shoji; Oyama, Yasuo

2018-09-01

The aim of this study was to investigate the effects of dibromoacetonitrile (DBAN), a by-product in water bacterial control, at sublethal concentrations on rat thymocytes, by using a cytometric technique with appropriate fluorescent dyes. By using this method, the possibility that DBAN induces cellular actions related to oxidative stress was assessed. DBAN reduced the content of cellular nonprotein thiols under Zn 2+ -free conditions. It elevated the intracellular level of Zn 2+ , being independent from external Zn 2+ . DBAN increased cell vulnerability to the cytotoxic action of hydrogen peroxide. These actions of DBAN were likely related to oxidative stress. DBAN is formed by the reaction of bromides and chlorinated oxidants during water disinfection. Hydrolysis of 2,2-dibromo-3-nitrilopropionamide, an antimicrobial used in hydraulic fracturing fluids for production of shale gas and oil, produces DBAN. Therefore, the concern regarding the levels of DBAN in industrial water systems is necessary to avoid the environmental risk to humans and wild mammals. Copyright © 2018 Elsevier Ltd. All rights reserved.

Cellular membrane trafficking of mesoporous silica nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Fang, I-Ju [Iowa State Univ., Ames, IA (United States)

2012-01-01

This dissertation mainly focuses on the investigation of the cellular membrane trafficking of mesoporous silica nanoparticles. We are interested in the study of endocytosis and exocytosis behaviors of mesoporous silica nanoparticles with desired surface functionality. The relationship between mesoporous silica nanoparticles and membrane trafficking of cells, either cancerous cells or normal cells was examined. Since mesoporous silica nanoparticles were applied in many drug delivery cases, the endocytotic efficiency of mesoporous silica nanoparticles needs to be investigated in more details in order to design the cellular drug delivery system in the controlled way. It is well known that cells can engulf some molecules outside of the cells through a receptor-ligand associated endocytosis. We are interested to determine if those biomolecules binding to cell surface receptors can be utilized on mesoporous silica nanoparticle materials to improve the uptake efficiency or govern the mechanism of endocytosis of mesoporous silica nanoparticles. Arginine-glycine-aspartate (RGD) is a small peptide recognized by cell integrin receptors and it was reported that avidin internalization was highly promoted by tumor lectin. Both RGD and avidin were linked to the surface of mesoporous silica nanoparticle materials to investigate the effect of receptor-associated biomolecule on cellular endocytosis efficiency. The effect of ligand types, ligand conformation and ligand density were discussed in Chapter 2 and 3. Furthermore, the exocytosis of mesoporous silica nanoparticles is very attractive for biological applications. The cellular protein sequestration study of mesoporous silica nanoparticles was examined for further information of the intracellular pathway of endocytosed mesoporous silica nanoparticle materials. The surface functionality of mesoporous silica nanoparticle materials demonstrated selectivity among the materials and cancer and normal cell lines. We aimed to determine

Effects of Exercise Training on Molecular Markers of Lipogenesis and Lipid Partitioning in Fructose-Induced Liver Fat Accumulation

Directory of Open Access Journals (Sweden)

Siham Yasari

2012-01-01

Full Text Available The present study was designed to investigate the impact of exercise training on lipogenic gene expression in liver and lipid partitioning following the ingestion of a high fructose load. Female rats were exercise-trained for 8 wk or kept sedentary before being submitted to a fasting/refeeding protocol. Rats were further subdivided as follow: rats were fasted for 24 h, refed a standard diet for 24 h, starved for another 24 h, and refed with a standard or a high-fructose diet 24 h before sacrifice. Fructose refeeding was associated with an increase in hepatic lipid content, endocannabinoid receptor 1, sterol regulatory element-binding protein1c, and stearoyl-CoA desaturase1 gene expression in both Sed and TR rats. However, desaturation indexes measured in liver (C16 : 1/C16 : 0 and C18 : 1/C18 : 0 and plasma (C18 : 1/C18 : 0 were higher (P<0.01 in TR than in Sed rats following fructose refeeding. It is concluded that exercise training does not significantly affect fat accumulation and the molecular expression of genes involved in lipogenesis after fasting and fructose refeeding but does modify the partitioning of lipids so as to provide more unsaturated fatty acids in liver without affecting liver fat content.

Design of a fault-tolerant reversible control unit in molecular quantum-dot cellular automata

Science.gov (United States)

Bahadori, Golnaz; Houshmand, Monireh; Zomorodi-Moghadam, Mariam

Quantum-dot cellular automata (QCA) is a promising emerging nanotechnology that has been attracting considerable attention due to its small feature size, ultra-low power consuming, and high clock frequency. Therefore, there have been many efforts to design computational units based on this technology. Despite these advantages of the QCA-based nanotechnologies, their implementation is susceptible to a high error rate. On the other hand, using the reversible computing leads to zero bit erasures and no energy dissipation. As the reversible computation does not lose information, the fault detection happens with a high probability. In this paper, first we propose a fault-tolerant control unit using reversible gates which improves on the previous design. The proposed design is then synthesized to the QCA technology and is simulated by the QCADesigner tool. Evaluation results indicate the performance of the proposed approach.

Phg1/TM9 proteins control intracellular killing of bacteria by determining cellular levels of the Kil1 sulfotransferase in Dictyostelium.

Directory of Open Access Journals (Sweden)

Marion Le Coadic

Full Text Available Dictyostelium discoideum has largely been used to study phagocytosis and intracellular killing of bacteria. Previous studies have shown that Phg1A, Kil1 and Kil2 proteins are necessary for efficient intracellular killing of Klebsiella bacteria. Here we show that in phg1a KO cells, cellular levels of lysosomal glycosidases and lysozyme are decreased, and lysosomal pH is increased. Surprisingly, overexpression of Kil1 restores efficient killing in phg1a KO cells without correcting these lysosomal anomalies. Conversely, kil1 KO cells are defective for killing, but their enzymatic content and lysosomal pH are indistinguishable from WT cells. The killing defect of phg1a KO cells can be accounted for by the observation that in these cells the stability and the cellular amount of Kil1 are markedly reduced. Since Kil1 is the only sulfotransferase characterized in Dictyostelium, an (unidentified sulfated factor, defective in both phg1a and kil1 KO cells, may play a key role in intracellular killing of Klebsiella bacteria. In addition, Phg1B plays a redundant role with Phg1A in controlling cellular amounts of Kil1 and intracellular killing. Finally, cellular levels of Kil1 are unaffected in kil2 KO cells, and Kil1 overexpression does not correct the killing defect of kil2 KO cells, suggesting that Kil2 plays a distinct role in intracellular killing.

Cellular MR Imaging

Directory of Open Access Journals (Sweden)

Michel Modo

2005-07-01

Full Text Available Cellular MR imaging is a young field that aims to visualize targeted cells in living organisms. In order to provide a different signal intensity of the targeted cell, they are either labeled with MR contrast agents in vivo or prelabeled in vitro. Either (ultrasmall superparamagnetic iron oxide [(USPIO] particles or (polymeric paramagnetic chelates can be used for this purpose. For in vivo cellular labeling, Gd3+- and Mn2+- chelates have mainly been used for targeted hepatobiliary imaging, and (USPIO-based cellular imaging has been focused on imaging of macrophage activity. Several of these magneto-pharmaceuticals have been FDA-approved or are in late-phase clinical trials. As for prelabeling of cells in vitro, a challenge has been to induce a sufficient uptake of contrast agents into nonphagocytic cells, without affecting normal cellular function. It appears that this issue has now largely been resolved, leading to an active research on monitoring the cellular biodistribution in vivo following transplantation or transfusion of these cells, including cell migration and trafficking. New applications of cellular MR imaging will be directed, for instance, towards our understanding of hematopoietic (immune cell trafficking and of novel guided (stem cell-based therapies aimed to be translated to the clinic in the future.

Correlating two-photon excited fluorescence imaging of breast cancer cellular redox state with seahorse flux analysis of normalized cellular oxygen consumption

Science.gov (United States)

Hou, Jue; Wright, Heather J.; Chan, Nicole; Tran, Richard; Razorenova, Olga V.; Potma, Eric O.; Tromberg, Bruce J.

2016-06-01

Two-photon excited fluorescence (TPEF) imaging of the cellular cofactors nicotinamide adenine dinucleotide and oxidized flavin adenine dinucleotide is widely used to measure cellular metabolism, both in normal and pathological cells and tissues. When dual-wavelength excitation is used, ratiometric TPEF imaging of the intrinsic cofactor fluorescence provides a metabolic index of cells-the "optical redox ratio" (ORR). With increased interest in understanding and controlling cellular metabolism in cancer, there is a need to evaluate the performance of ORR in malignant cells. We compare TPEF metabolic imaging with seahorse flux analysis of cellular oxygen consumption in two different breast cancer cell lines (MCF-7 and MDA-MB-231). We monitor metabolic index in living cells under both normal culture conditions and, for MCF-7, in response to cell respiration inhibitors and uncouplers. We observe a significant correlation between the TPEF-derived ORR and the flux analyzer measurements (R=0.7901, p<0.001). Our results confirm that the ORR is a valid dynamic index of cell metabolism under a range of oxygen consumption conditions relevant for cancer imaging.

Stochastic fluctuations and distributed control of gene expression impact cellular memory.

Directory of Open Access Journals (Sweden)

Guillaume Corre

Full Text Available Despite the stochastic noise that characterizes all cellular processes the cells are able to maintain and transmit to their daughter cells the stable level of gene expression. In order to better understand this phenomenon, we investigated the temporal dynamics of gene expression variation using a double reporter gene model. We compared cell clones with transgenes coding for highly stable mRNA and fluorescent proteins with clones expressing destabilized mRNA-s and proteins. Both types of clones displayed strong heterogeneity of reporter gene expression levels. However, cells expressing stable gene products produced daughter cells with similar level of reporter proteins, while in cell clones with short mRNA and protein half-lives the epigenetic memory of the gene expression level was completely suppressed. Computer simulations also confirmed the role of mRNA and protein stability in the conservation of constant gene expression levels over several cell generations. These data indicate that the conservation of a stable phenotype in a cellular lineage may largely depend on the slow turnover of mRNA-s and proteins.

47 CFR 22.970 - Unacceptable interference to part 90 non-cellular 800 MHz licensees from cellular radiotelephone...

Science.gov (United States)

2010-10-01

...-cellular 800 MHz licensees from cellular radiotelephone or part 90-800 MHz cellular systems. 22.970 Section... MOBILE SERVICES Cellular Radiotelephone Service § 22.970 Unacceptable interference to part 90 non-cellular 800 MHz licensees from cellular radiotelephone or part 90-800 MHz cellular systems. (a) Definition...

Humoral and cellular immunity in women with infertility (dynamic observation after Chernobyl accident)

International Nuclear Information System (INIS)

Dubchak, A.Je.

2000-01-01

The influence of low-dose radiation on the state of humoral and cellular immunity in women with infertility of inflammatory origin during a dynamic study was studied. The data of the dynamic study of cellular and humoral immunity in women with inflammatory infertility evacuated from Chernobyl and Pripyat and in those constantly residing on the controlled territories compared to those living in Poltava, the differences suggesting unfavorable influence of harmful factors (including low-dose radiation) on the organism of the woman have been revealed. In the evacuated women the changes in cellular and humoral immunity were observed during the first years after the accident, while in those residing in the controlled territories 4-5 years after the accident

Nonsynchronous updating in the multiverse of cellular automata.

Science.gov (United States)

Reia, Sandro M; Kinouchi, Osame

2015-04-01

In this paper we study updating effects on cellular automata rule space. We consider a subset of 6144 order-3 automata from the space of 262144 bidimensional outer-totalistic rules. We compare synchronous to asynchronous and sequential updatings. Focusing on two automata, we discuss how update changes destroy typical structures of these rules. Besides, we show that the first-order phase transition in the multiverse of synchronous cellular automata, revealed with the use of a recently introduced control parameter, seems to be robust not only to changes in update schema but also to different initial densities.

Nonsynchronous updating in the multiverse of cellular automata

Science.gov (United States)

Reia, Sandro M.; Kinouchi, Osame

2015-04-01

In this paper we study updating effects on cellular automata rule space. We consider a subset of 6144 order-3 automata from the space of 262144 bidimensional outer-totalistic rules. We compare synchronous to asynchronous and sequential updatings. Focusing on two automata, we discuss how update changes destroy typical structures of these rules. Besides, we show that the first-order phase transition in the multiverse of synchronous cellular automata, revealed with the use of a recently introduced control parameter, seems to be robust not only to changes in update schema but also to different initial densities.

Cellular mechanisms that control mistranslation

DEFF Research Database (Denmark)

Reynolds, Noah M; Lazazzera, Beth A; Ibba, Michael

2010-01-01

Mistranslation broadly encompasses the introduction of errors during any step of protein synthesis, leading to the incorporation of an amino acid that is different from the one encoded by the gene. Recent research has vastly enhanced our understanding of the mechanisms that control mistranslation...... at the molecular level and has led to the discovery that the rates of mistranslation in vivo are not fixed but instead are variable. In this Review we describe the different steps in translation quality control and their variations under different growth conditions and between species though a comparison...

Iterative feedback bio-printing-derived cell-laden hydrogel scaffolds with optimal geometrical fidelity and cellular controllability.

Science.gov (United States)

Wang, Ling; Xu, Ming-En; Luo, Li; Zhou, Yongyong; Si, Peijian

2018-02-12

For three-dimensional bio-printed cell-laden hydrogel tissue constructs, the well-designed internal porous geometry is tailored to obtain the desired structural and cellular properties. However, significant differences often exist between the designed and as-printed scaffolds because of the inherent characteristics of hydrogels and cells. In this study, an iterative feedback bio-printing (IFBP) approach based on optical coherence tomography (OCT) for the fabrication of cell-laden hydrogel scaffolds with optimal geometrical fidelity and cellular controllability was proposed. A custom-made swept-source OCT (SS-OCT) system was applied to characterize the printed scaffolds quantitatively. Based on the obtained empirical linear formula from the first experimental feedback loop, we defined the most appropriate design constraints and optimized the printing process to improve the geometrical fidelity. The effectiveness of IFBP was verified from the second run using gelatin/alginate hydrogel scaffolds laden with C3A cells. The mismatch of the morphological parameters greatly decreased from 40% to within 7%, which significantly optimized the cell viability, proliferation, and morphology, as well as the representative expression of hepatocyte markers, including CYP3A4 and albumin, of the printed cell-laden hydrogel scaffolds. The demonstrated protocol paves the way for the mass fabrication of cell-laden hydrogel scaffolds, engineered tissues, and scaled-up applications of the 3D bio-printing technique.

Heterogeneous cellular networks

CERN Document Server

Hu, Rose Qingyang

2013-01-01

A timely publication providing coverage of radio resource management, mobility management and standardization in heterogeneous cellular networks The topic of heterogeneous cellular networks has gained momentum in industry and the research community, attracting the attention of standardization bodies such as 3GPP LTE and IEEE 802.16j, whose objectives are looking into increasing the capacity and coverage of the cellular networks. This book focuses on recent progresses,  covering the related topics including scenarios of heterogeneous network deployment, interference management i

Design and Evaluation of IP Header Compression for Cellular-Controlled P2P Networks

DEFF Research Database (Denmark)

Madsen, T.K.; Zhang, Qi; Fitzek, F.H.P.

2007-01-01

In this paper we advocate to exploit terminal cooperation to stabilize IP communication using header compression. The terminal cooperation is based on direct communication between terminals using short range communication and simultaneously being connected to the cellular service access point....... The short range link is than used to provide first aid information to heal the decompressor state of the neighboring node in case of a packet loss on the cellular link. IP header compression schemes are used to increase the spectral and power efficiency loosing robustness of the communication compared...

Managing the cellular redox hub in photosynthetic organisms.

Science.gov (United States)

Foyer, Christine H; Noctor, Graham

2012-02-01

Light-driven redox chemistry is a powerful source of redox signals that has a decisive input into transcriptional control within the cell nucleus. Like photosynthetic electron transport pathways, the respiratory electron transport chain exerts a profound control over gene function, in order to balance energy (reductant and ATP) supply with demand, while preventing excessive over-reduction or over-oxidation that would be adversely affect metabolism. Photosynthetic and respiratory redox chemistries are not merely housekeeping processes but they exert a controlling influence over every aspect of plant biology, participating in the control of gene transcription and translation, post-translational modifications and the regulation of assimilatory reactions, assimilate partitioning and export. The number of processes influenced by redox controls and signals continues to increase as do the components that are recognized participants in the associated signalling pathways. A step change in our understanding of the overall importance of the cellular redox hub to plant cells has occurred in recent years as the complexity of the management of the cellular redox hub in relation to metabolic triggers and environmental cues has been elucidated. This special issue describes aspects of redox regulation and signalling at the cutting edge of current research in this dynamic and rapidly expanding field. © 2011 Blackwell Publishing Ltd.

47 CFR 22.909 - Cellular markets.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular markets. 22.909 Section 22.909... Cellular Radiotelephone Service § 22.909 Cellular markets. Cellular markets are standard geographic areas used by the FCC for administrative convenience in the licensing of cellular systems. Cellular markets...

Mir-513a-3p contributes to the controlling of cellular migration processes in the A549 lung tumor cells by modulating integrin β-8 expression.

Science.gov (United States)

da Silveira, Marina Bonfogo; Lima, Kelvin Furtado; da Silva, Andrea Renata; Dos Santos, Robson Augusto Souza; Moraes, Karen C M

2017-12-04

Lung tumors are a frequent type of cancer in humans and a leading cause of death, and the late diagnostic contributes to high mortality rates. New therapeutic strategies are needed, and the heptapeptide angiotensin-(1-7) [ang-(1-7)] demonstrated the ability to control cancer growth rates and migration in vitro and in vivo. However, the possible use of the heptapeptide in clinical trials demands deeper analyses to elucidate molecular mechanisms of its effect in the target cells. In this study, we investigated relevant elements that control pro-inflammatory environment and cellular migration, focusing in the post-transcription mechanism using lung tumor cell line. In our cellular model, the microRNA-513a-3p was identified as a novel element targeting ITG-β8, thereby controlling the protein level and its molecular function in the controlling of migration and pro-inflammatory environment. These findings provide useful information for future studies, using miR-513a-3p as an innovative molecular tool to control lung tumor cell migration, which will support more effective clinical treatment of the patients with the widely used chemotherapeutic agents, increasing survival rates.

Targeting Mitochondria to Counteract Age-Related Cellular Dysfunction

Directory of Open Access Journals (Sweden)

Corina T. Madreiter-Sokolowski

2018-03-01

Full Text Available Senescence is related to the loss of cellular homeostasis and functions, which leads to a progressive decline in physiological ability and to aging-associated diseases. Since mitochondria are essential to energy supply, cell differentiation, cell cycle control, intracellular signaling and Ca2+ sequestration, fine-tuning mitochondrial activity appropriately, is a tightrope walk during aging. For instance, the mitochondrial oxidative phosphorylation (OXPHOS ensures a supply of adenosine triphosphate (ATP, but is also the main source of potentially harmful levels of reactive oxygen species (ROS. Moreover, mitochondrial function is strongly linked to mitochondrial Ca2+ homeostasis and mitochondrial shape, which undergo various alterations during aging. Since mitochondria play such a critical role in an organism’s process of aging, they also offer promising targets for manipulation of senescent cellular functions. Accordingly, interventions delaying the onset of age-associated disorders involve the manipulation of mitochondrial function, including caloric restriction (CR or exercise, as well as drugs, such as metformin, aspirin, and polyphenols. In this review, we discuss mitochondria’s role in and impact on cellular aging and their potential to serve as a target for therapeutic interventions against age-related cellular dysfunction.

Cellular self-assembly and biomaterials-based organoid models of development and diseases.

Science.gov (United States)

Shah, Shivem B; Singh, Ankur

2017-04-15

Organogenesis and morphogenesis have informed our understanding of physiology, pathophysiology, and avenues to create new curative and regenerative therapies. Thus far, this understanding has been hindered by the lack of a physiologically relevant yet accessible model that affords biological control. Recently, three-dimensional ex vivo cellular cultures created through cellular self-assembly under natural extracellular matrix cues or through biomaterial-based directed assembly have been shown to physically resemble and recapture some functionality of target organs. These "organoids" have garnered momentum for their applications in modeling human development and disease, drug screening, and future therapy design or even organ replacement. This review first discusses the self-organizing organoids as materials with emergent properties and their advantages and limitations. We subsequently describe biomaterials-based strategies used to afford more control of the organoid's microenvironment and ensuing cellular composition and organization. In this review, we also offer our perspective on how multifunctional biomaterials with precise spatial and temporal control could ultimately bridge the gap between in vitro organoid platforms and their in vivo counterparts. Several notable reviews have highlighted PSC-derived organoids and 3D aggregates, including embryoid bodies, from a development and cellular assembly perspective. The focus of this review is to highlight the materials-based approaches that cells, including PSCs and others, adopt for self-assembly and the controlled development of complex tissues, such as that of the brain, gut, and immune system. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Modeling virtualized downlink cellular networks with ultra-dense small cells

KAUST Repository

Ibrahim, Hazem

2015-09-11

The unrelenting increase in the mobile users\\' populations and traffic demand drive cellular network operators to densify their infrastructure. Network densification increases the spatial frequency reuse efficiency while maintaining the signal-to-interference-plus-noise-ratio (SINR) performance, hence, increases the spatial spectral efficiency and improves the overall network performance. However, control signaling in such dense networks consumes considerable bandwidth and limits the densification gain. Radio access network (RAN) virtualization via control plane (C-plane) and user plane (U-plane) splitting has been recently proposed to lighten the control signaling burden and improve the network throughput. In this paper, we present a tractable analytical model for virtualized downlink cellular networks, using tools from stochastic geometry. We then apply the developed modeling framework to obtain design insights for virtualized RANs and quantify associated performance improvement. © 2015 IEEE.

Biomechanics of cellular solids.

Science.gov (United States)

Gibson, Lorna J

2005-03-01

Materials with a cellular structure are widespread in nature and include wood, cork, plant parenchyma and trabecular bone. Natural cellular materials are often mechanically efficient: the honeycomb-like microstructure of wood, for instance, gives it an exceptionally high performance index for resisting bending and buckling. Here we review the mechanics of a wide range of natural cellular materials and examine their role in lightweight natural sandwich structures (e.g. iris leaves) and natural tubular structures (e.g. plant stems or animal quills). We also describe two examples of engineered biomaterials with a cellular structure, designed to replace or regenerate tissue in the body.

Influence of postoperative enteral nutrition on cellular immunity. A random double-blinded placebo controlled clinical trial

DEFF Research Database (Denmark)

Beier-Holgersen, R; Brandstrup, B

2012-01-01

The aim of this study was to discover if the cellular immunological response is different in patients receiving early postoperative enteral nutrition compared to patients who only receive "water".......The aim of this study was to discover if the cellular immunological response is different in patients receiving early postoperative enteral nutrition compared to patients who only receive "water"....

A new concept for medical imaging centered on cellular phone technology.

Directory of Open Access Journals (Sweden)

Yair Granot

2008-04-01

Full Text Available According to World Health Organization reports, some three quarters of the world population does not have access to medical imaging. In addition, in developing countries over 50% of medical equipment that is available is not being used because it is too sophisticated or in disrepair or because the health personnel are not trained to use it. The goal of this study is to introduce and demonstrate the feasibility of a new concept in medical imaging that is centered on cellular phone technology and which may provide a solution to medical imaging in underserved areas. The new system replaces the conventional stand-alone medical imaging device with a new medical imaging system made of two independent components connected through cellular phone technology. The independent units are: a a data acquisition device (DAD at a remote patient site that is simple, with limited controls and no image display capability and b an advanced image reconstruction and hardware control multiserver unit at a central site. The cellular phone technology transmits unprocessed raw data from the patient site DAD and receives and displays the processed image from the central site. (This is different from conventional telemedicine where the image reconstruction and control is at the patient site and telecommunication is used to transmit processed images from the patient site. The primary goal of this study is to demonstrate that the cellular phone technology can function in the proposed mode. The feasibility of the concept is demonstrated using a new frequency division multiplexing electrical impedance tomography system, which we have developed for dynamic medical imaging, as the medical imaging modality. The system is used to image through a cellular phone a simulation of breast cancer tumors in a medical imaging diagnostic mode and to image minimally invasive tissue ablation with irreversible electroporation in a medical imaging interventional mode.

Analytical modeling of mode selection and power control for underlay D2D communication in cellular networks

KAUST Repository

Elsawy, Hesham; Hossain, Ekram; Alouini, Mohamed-Slim

2014-01-01

Device-to-device (D2D) communication enables the user equipments (UEs) located in close proximity to bypass the cellular base stations (BSs) and directly connect to each other, and thereby, offload traffic from the cellular infrastructure. D2D

Cellular Reflectarray Antenna

Science.gov (United States)

Romanofsky, Robert R.

2010-01-01

The cellular reflectarray antenna is intended to replace conventional parabolic reflectors that must be physically aligned with a particular satellite in geostationary orbit. These arrays are designed for specified geographical locations, defined by latitude and longitude, each called a "cell." A particular cell occupies nominally 1,500 square miles (3,885 sq. km), but this varies according to latitude and longitude. The cellular reflectarray antenna designed for a particular cell is simply positioned to align with magnetic North, and the antenna surface is level (parallel to the ground). A given cellular reflectarray antenna will not operate in any other cell.

Freshwater Clam Extract Ameliorates Triglyceride and Cholesterol Metabolism through the Expression of Genes Involved in Hepatic Lipogenesis and Cholesterol Degradation in Rats

Directory of Open Access Journals (Sweden)

Thomas Laurent

2013-01-01

Full Text Available The freshwater clam (Corbicula spp. is a popular edible bivalve and has been used as a folk remedy for liver disease in Asia. As a Chinese traditional medicine, it is said that freshwater clam ameliorates alcoholic intoxication and cholestasis. In this study, to estimate the practical benefit of freshwater clam extract (FCE, we compared the effects of FCE and soy protein isolate (SPI on triglyceride and cholesterol metabolism in rats. FCE and SPI lowered serum cholesterol, and FCE tended to reduce serum triglycerides. FCE enhanced fecal sterol excretion and hepatic mRNA levels of CYP7A1 and ABCG5 more substantially than SPI; however, both diets reduced hepatic cholesterol. Both of the diets similarly suppressed liver lipids improved Δ9-desaturated fatty acid profile, and FCE was associated with a reduction in FAS and SCD1 mRNA levels. Hepatic transcriptome analysis revealed that inhibition of lipogenesis-related gene expression may contribute to downregulation of hepatic triglycerides by FCE. FCE would have better potential benefits for preventing metabolic disorders, through greater improvement of metabolism of triglycerides and cholesterol, likely through a mechanism similar to SPI.

Selective LXRα inhibitory effects observed in plant extracts of MEH184 (Parthenocissua tricuspidata) and MEH185 (Euscaphis japonica)

International Nuclear Information System (INIS)

Kim, Kang Ho; Choi, Seung Hyun; Lee, Thomas S.; Oh, Won Keun; Kim, Dong Sun; Kim, Jae Bum

2006-01-01

Liver X receptors (LXRs) are nuclear hormone receptors that behave as lipid sensors of cellular cholesterol and fatty acid. Although LXR activation can alleviate hypercholesterolemia by inducing cholesterol efflux, it also results in undesirable effects of fatty acid synthesis, resulting in hepatic steatosis and hyperlipidemia. Therefore, it is critical to identify LXRα inhibitory agents that would repress fatty acid synthesis and hepatic lipid accumulation. In current study, screening of plant extracts used for traditional oriental medicine resulted in the identification of two candidates demonstrating selective LXRα inhibitory activity. These were whole leaf methanol extracts of Parthenocissua tricuspidata (MEH184) and Euscaphis japonica (MEH185). Both MEH184 and MEH185 decreased transcriptional activity of LXRα and the expression of LXRα target genes, such as FAS and ADD1/SREBP1c. Additionally, MEH184 and MEH184 significantly reduced lipogenesis and adipocyte differentiation. Together, the data imply that MEH184 and MEH185 possess selective antagonistic properties on LXRα to downregulate lipogenesis

Linearizable cellular automata

International Nuclear Information System (INIS)

Nobe, Atsushi; Yura, Fumitaka

2007-01-01

The initial value problem for a class of reversible elementary cellular automata with periodic boundaries is reduced to an initial-boundary value problem for a class of linear systems on a finite commutative ring Z 2 . Moreover, a family of such linearizable cellular automata is given

Electromagnetic cellular interactions.

Science.gov (United States)

Cifra, Michal; Fields, Jeremy Z; Farhadi, Ashkan

2011-05-01

Chemical and electrical interaction within and between cells is well established. Just the opposite is true about cellular interactions via other physical fields. The most probable candidate for an other form of cellular interaction is the electromagnetic field. We review theories and experiments on how cells can generate and detect electromagnetic fields generally, and if the cell-generated electromagnetic field can mediate cellular interactions. We do not limit here ourselves to specialized electro-excitable cells. Rather we describe physical processes that are of a more general nature and probably present in almost every type of living cell. The spectral range included is broad; from kHz to the visible part of the electromagnetic spectrum. We show that there is a rather large number of theories on how cells can generate and detect electromagnetic fields and discuss experimental evidence on electromagnetic cellular interactions in the modern scientific literature. Although small, it is continuously accumulating. Copyright © 2010 Elsevier Ltd. All rights reserved.

Specific Human and Candida Cellular Interactions Lead to Controlled or Persistent Infection Outcomes during Granuloma-Like Formation.

Science.gov (United States)

Misme-Aucouturier, Barbara; Albassier, Marjorie; Alvarez-Rueda, Nidia; Le Pape, Patrice

2017-01-01

A delayed type of multicellular process could be crucial during chronic candidiasis in determining the course of infection. This reaction, consisting of organized immune cells surrounding the pathogen, initiates an inflammatory response to avoid fungal dissemination. The goal of the present study was to examine, at an in vitro cellular scale, Candida and human immune cell interaction dynamics during a long-term period. By challenging human peripheral blood immune cells from 10 healthy donors with 32 Candida albicans and non-albicans (C. glabrata, C. tropicalis, C. parapsilosis, C. dubliniensis, C. lusitaniae, C. krusei, and C. kefyr) clinical isolates, we showed that Candida spp. induced the formation of granuloma-like structures within 6 days after challenge, but their sizes and the respective fungal burdens differed according to the Candida species. These two parameters are positively correlated. Phenotypic characteristics, such as hypha formation and higher axenic growth rate, seem to contribute to yeast persistence within granuloma-like structures. We showed an interindividual variability of the human response against Candida spp. Higher proportions of neutrophils and elevated CD4 + /CD8 + T cell ratios during the first days after challenge were correlated with early production of gamma interferon (IFN-γ) and associated with controlled infection. In contrast, the persistence of Candida could result from upregulation of proinflammatory cytokines such as interleukin-6 (IL-6), IFN-γ, and tumor necrosis factor alpha (TNF-α) and a poor anti-inflammatory negative feedback (IL-10). Importantly, regulatory subsets of NK cells and CD4 lo CD8 hi doubly positive (DP) lymphocytes at late stage infiltrate granuloma-like structures and could correlate with the IL-10 and TNF-α production. These data offer a base frame to explain cellular events that guide infection control or fungal persistence. Copyright © 2016 Misme-Aucouturier et al.

On stochastic geometry modeling of cellular uplink transmission with truncated channel inversion power control

KAUST Repository

Elsawy, Hesham

2014-08-01

Using stochastic geometry, we develop a tractable uplink modeling paradigm for outage probability and spectral efficiency in both single and multi-tier cellular wireless networks. The analysis accounts for per user equipment (UE) power control as well as the maximum power limitations for UEs. More specifically, for interference mitigation and robust uplink communication, each UE is required to control its transmit power such that the average received signal power at its serving base station (BS) is equal to a certain threshold ρo. Due to the limited transmit power, the UEs employ a truncated channel inversion power control policy with a cutoff threshold of ρo. We show that there exists a transfer point in the uplink system performance that depends on the following tuple: BS intensity λ, maximum transmit power of UEs Pu, and ρo. That is, when Pu is a tight operational constraint with respect to (w.r.t.) λ and ρo, the uplink outage probability and spectral efficiency highly depend on the values of λ and ρo. In this case, there exists an optimal cutoff threshold ρ*o, which depends on the system parameters, that minimizes the outage probability. On the other hand, when Pu is not a binding operational constraint w.r.t. λ and ρo, the uplink outage probability and spectral efficiency become independent of λ and ρo. We obtain approximate yet accurate simple expressions for outage probability and spectral efficiency, which reduce to closed forms in some special cases. © 2002-2012 IEEE.

DNA supercoiling: changes during cellular differentiation and activation of chromatin transcription

International Nuclear Information System (INIS)

Luchnik, A.N.; Bakayev, V.V.; Glaser, V.M.; Moscow State Univ., USSR)

1983-01-01

In this paper it is reported that elastic DNA torsional tension has been observed in a fraction of isolated SV40 minichromosomes, which are shown to be transcriptionally active, and that the number of DNA topological (titratable superhelical) turns in closed superhelical loops of nuclear DNA decreases during cellular differentiation, which, we propose, may be responsible for the coordinate switch in transcription of genes controlling cellular proliferation. 37 references, 6 figures, 2 tables

Optically-controlled platforms for transfection and single- and sub-cellular surgery

DEFF Research Database (Denmark)

Villangca, Mark Jayson; Casey, Duncan; Glückstad, Jesper

2015-01-01

and specificity of optical trapping in conjunction with other modalities to perform single and sub-cellular surgery. These tools form highly tuneable platforms for the delivery or removal of material from cells of interest, but can simultaneously excite fluorescent probes for imaging purposes or plasmonic...... structures for very local heating. We discuss both the history and recent applications of the field, highlighting the key findings and developments over the last 40 years of biophotonics research....

A Cellular Automata Model of Infection Control on Medical Implants

Science.gov (United States)

Prieto-Langarica, Alicia; Kojouharov, Hristo; Chen-Charpentier, Benito; Tang, Liping

2011-01-01

S. epidermidis infections on medically implanted devices are a common problem in modern medicine due to the abundance of the bacteria. Once inside the body, S. epidermidis gather in communities called biofilms and can become extremely hard to eradicate, causing the patient serious complications. We simulate the complex S. epidermidis-Neutrophils interactions in order to determine the optimum conditions for the immune system to be able to contain the infection and avoid implant rejection. Our cellular automata model can also be used as a tool for determining the optimal amount of antibiotics for combating biofilm formation on medical implants. PMID:23543851

Modeling and Analysis of Cellular Networks using Stochastic Geometry: A Tutorial

KAUST Repository

Elsawy, Hesham; Salem, Ahmed Sultan; Alouini, Mohamed-Slim; Win, Moe Z.

2016-01-01

This paper presents a tutorial on stochastic geometry (SG) based analysis for cellular networks. This tutorial is distinguished by its depth with respect to wireless communication details and its focus on cellular networks. The paper starts by modeling and analyzing the baseband interference in a baseline single-tier downlink cellular network with single antenna base stations and universal frequency reuse. Then, it characterizes signal-to-interference-plus-noise-ratio (SINR) and its related performance metrics. In particular, a unified approach to conduct error probability, outage probability, and transmission rate analysis is presented. Although the main focus of the paper is on cellular networks, the presented unified approach applies for other types of wireless networks that impose interference protection around receivers. The paper then extends the unified approach to capture cellular network characteristics (e.g., frequency reuse, multiple antenna, power control, etc.). It also presents numerical examples associated with demonstrations and discussions. To this end, the paper highlights the state-of-the- art research and points out future research directions.

Modeling and Analysis of Cellular Networks using Stochastic Geometry: A Tutorial

KAUST Repository

Elsawy, Hesham

2016-11-03

This paper presents a tutorial on stochastic geometry (SG) based analysis for cellular networks. This tutorial is distinguished by its depth with respect to wireless communication details and its focus on cellular networks. The paper starts by modeling and analyzing the baseband interference in a baseline single-tier downlink cellular network with single antenna base stations and universal frequency reuse. Then, it characterizes signal-to-interference-plus-noise-ratio (SINR) and its related performance metrics. In particular, a unified approach to conduct error probability, outage probability, and transmission rate analysis is presented. Although the main focus of the paper is on cellular networks, the presented unified approach applies for other types of wireless networks that impose interference protection around receivers. The paper then extends the unified approach to capture cellular network characteristics (e.g., frequency reuse, multiple antenna, power control, etc.). It also presents numerical examples associated with demonstrations and discussions. To this end, the paper highlights the state-of-the- art research and points out future research directions.

Cellular Particle Dynamics simulation of biomechanical relaxation processes of multi-cellular systems

Science.gov (United States)

McCune, Matthew; Kosztin, Ioan

2013-03-01

Cellular Particle Dynamics (CPD) is a theoretical-computational-experimental framework for describing and predicting the time evolution of biomechanical relaxation processes of multi-cellular systems, such as fusion, sorting and compression. In CPD, cells are modeled as an ensemble of cellular particles (CPs) that interact via short range contact interactions, characterized by an attractive (adhesive interaction) and a repulsive (excluded volume interaction) component. The time evolution of the spatial conformation of the multicellular system is determined by following the trajectories of all CPs through numerical integration of their equations of motion. Here we present CPD simulation results for the fusion of both spherical and cylindrical multi-cellular aggregates. First, we calibrate the relevant CPD model parameters for a given cell type by comparing the CPD simulation results for the fusion of two spherical aggregates to the corresponding experimental results. Next, CPD simulations are used to predict the time evolution of the fusion of cylindrical aggregates. The latter is relevant for the formation of tubular multi-cellular structures (i.e., primitive blood vessels) created by the novel bioprinting technology. Work supported by NSF [PHY-0957914]. Computer time provided by the University of Missouri Bioinformatics Consortium.

Selfish cellular networks and the evolution of complex organisms.

Science.gov (United States)

Kourilsky, Philippe

2012-03-01

Human gametogenesis takes years and involves many cellular divisions, particularly in males. Consequently, gametogenesis provides the opportunity to acquire multiple de novo mutations. A significant portion of these is likely to impact the cellular networks linking genes, proteins, RNA and metabolites, which constitute the functional units of cells. A wealth of literature shows that these individual cellular networks are complex, robust and evolvable. To some extent, they are able to monitor their own performance, and display sufficient autonomy to be termed "selfish". Their robustness is linked to quality control mechanisms which are embedded in and act upon the individual networks, thereby providing a basis for selection during gametogenesis. These selective processes are equally likely to affect cellular functions that are not gamete-specific, and the evolution of the most complex organisms, including man, is therefore likely to occur via two pathways: essential housekeeping functions would be regulated and evolve during gametogenesis within the parents before being transmitted to their progeny, while classical selection would operate on other traits of the organisms that shape their fitness with respect to the environment. Copyright © 2012 Académie des sciences. Published by Elsevier SAS. All rights reserved.

Cellular automata in photonic cavity arrays.

Science.gov (United States)

Li, Jing; Liew, T C H

2016-10-31

We propose theoretically a photonic Turing machine based on cellular automata in arrays of nonlinear cavities coupled with artificial gauge fields. The state of the system is recorded making use of the bistability of driven cavities, in which losses are fully compensated by an external continuous drive. The sequential update of the automaton layers is achieved automatically, by the local switching of bistable states, without requiring any additional synchronization or temporal control.

A new cellular automaton for signal controlled traffic flow based on driving behaviors

Science.gov (United States)

Wang, Yang; Chen, Yan-Yan

2015-03-01

The complexity of signal controlled traffic largely stems from the various driving behaviors developed in response to the traffic signal. However, the existing models take a few driving behaviors into account and consequently the traffic dynamics has not been completely explored. Therefore, a new cellular automaton model, which incorporates the driving behaviors typically manifesting during the different stages when the vehicles are moving toward a traffic light, is proposed in this paper. Numerical simulations have demonstrated that the proposed model can produce the spontaneous traffic breakdown and the dissolution of the over-saturated traffic phenomena. Furthermore, the simulation results indicate that the slow-to-start behavior and the inch-forward behavior can foster the traffic breakdown. Particularly, it has been discovered that the over-saturated traffic can be revised to be an under-saturated state when the slow-down behavior is activated after the spontaneous breakdown. Finally, the contributions of the driving behaviors on the traffic breakdown have been examined. Project supported by the National Basic Research Program of China (Grand No. 2012CB723303) and the Beijing Committee of Science and Technology, China (Grand No. Z1211000003120100).

[Morphochemical changes in the substantia nigra cellular structures in Parkinson's disease].

Science.gov (United States)

Salkov, V N; Khudoerkov, R M; Voronkov, D N; Sobolev, V B; Kutukova, K A

to clarify the features of morphochemical changes in the substantia nigra cellular structures in Parkinson's disease. The structural characteristics of the substantia nigra were studied microscopically and quantified using computer morphometric methods at brain autopsies of individuals with Parkinson's disease who had died from intercurrent diseases and those who had no evidence of neurological disorders in their history (a control group). This investigation could clarify the features of morphochemical changes in both the neural network structures and the glial populations of the substantia nigra in Parkinson's disease. The number of neurons containing tyrosine hydroxylase (a marker of dopamine neurons) in the compact part of the substantia nigra (a ventral region) was smaller and the density distribution of Lewy bodies was higher in the patients with Parkinson's disease than in the control group. The accumulation of iron (II) compounds in the cellular elements and neuropile and the increased expression of glial fibrillary acidic protein in Parkinson's disease were more pronounced than those in the controls. Postmortem diagnosis in Parkinson's disease should be based on a full description of a set of neuronal and glial morphochemical and structural changes in the substantia nigra rather than on the identification of cellular markers for the neurodegenerative process.

Cellular phones, cordless phones, and the risks of glioma and meningioma (Interphone Study Group, Germany)

DEFF Research Database (Denmark)

Schüz, Joachim; Böhler, Eva; Berg, Gabriele

2006-01-01

The widespread use of cellular telephones has generated concern about possible adverse health effects, particularly brain tumors. In this population-based case-control study carried out in three regions of Germany, all incident cases of glioma and meningioma among patients aged 30-69 years were...... ascertained during 2000-2003. Controls matched on age, gender, and region were randomly drawn from population registries. In total, 366 glioma cases, 381 meningioma cases, and 1,494 controls were interviewed. Overall use of a cellular phone was not associated with brain tumor risk; the respective odds ratios...

Suitability of the cellular viability technique as a control tool of the chlorine dosage on the activated sludge of a biological process affected by bulking

International Nuclear Information System (INIS)

Montaya Martinez, T.; Zornoza Zornoza, A.; Granell Munoz, P.; Fayos, G.; Fajarddo, V.; Zorrilla, F.; Alonso Molina, J. L.; Morenilla Martinez, J. J.; Bernacer Bonora, I.; Martinez Francisco, F. J.

2009-01-01

This work demonstrates the suitability of the cellular viability technique as a control tool of the chlorine dosage on the activated sludge of a biological process affected by the overabundance of the filamentous bacteria (Thiothrix-021N). This technique was used to establish the chlorine dosage according to the observed damages on cellular membranes of both, floc-forming bacteria as well as filamentous bacteria. To identify the filamentous bacteria responsible for the macro-structural alteration of the flocs, several criteria were, met, including morphologic characteristics as well as conventional microbiological stains: Gram, Neisser and polyhydroxy alkanoates. FISH was used to confirm the obtained results, providing a definitive identification of the filamentous bacteria responsible for the alteration. (Author) 11 refs

Dynamic behavior of cellular materials and cellular structures: Experiments and modeling

Science.gov (United States)

Gao, Ziyang

Cellular solids, including cellular materials and cellular structures (CMS), have attracted people's great interests because of their low densities and novel physical, mechanical, thermal, electrical and acoustic properties. They offer potential for lightweight structures, energy absorption, thermal management, etc. Therefore, the studies of cellular solids have become one of the hottest research fields nowadays. From energy absorption point of view, any plastically deformed structures can be divided into two types (called type I and type II), and the basic cells of the CMS may take the configurations of these two types of structures. Accordingly, separated discussions are presented in this thesis. First, a modified 1-D model is proposed and numerically solved for a typical type II structure. Good agreement is achieved with the previous experimental data, hence is used to simulate the dynamic behavior of a type II chain. Resulted from different load speeds, interesting collapse modes are observed, and the parameters which govern the cell's post-collapse behavior are identified through a comprehensive non-dimensional analysis on general cellular chains. Secondly, the MHS specimens are chosen as an example of type I foam materials because of their good uniformity of the cell geometry. An extensive experimental study was carried out, where more attention was paid to their responses to dynamic loadings. Great enhancement of the stress-strain curve was observed in dynamic cases, and the energy absorption capacity is found to be several times higher than that of the commercial metal foams. Based on the experimental study, finite elemental simulations and theoretical modeling are also conducted, achieving good agreements and demonstrating the validities of those models. It is believed that the experimental, numerical and analytical results obtained in the present study will certainly deepen the understanding of the unsolved fundamental issues on the mechanical behavior of

Effects of Dietary Fructose Restriction on Liver Fat, De Novo Lipogenesis, and Insulin Kinetics in Children With Obesity.

Science.gov (United States)

Schwarz, Jean-Marc; Noworolski, Susan M; Erkin-Cakmak, Ayca; Korn, Natalie J; Wen, Michael J; Tai, Viva W; Jones, Grace M; Palii, Sergiu P; Velasco-Alin, Moises; Pan, Karen; Patterson, Bruce W; Gugliucci, Alejandro; Lustig, Robert H; Mulligan, Kathleen

2017-09-01

Consumption of sugar is associated with obesity, type 2 diabetes mellitus, nonalcoholic fatty liver disease, and cardiovascular disease. The conversion of fructose to fat in liver (de novo lipogenesis [DNL]) may be a modifiable pathogenetic pathway. We determined the effect of 9 days of isocaloric fructose restriction on DNL, liver fat, visceral fat (VAT), subcutaneous fat, and insulin kinetics in obese Latino and African American children with habitual high sugar consumption (fructose intake >50 g/d). Children (9-18 years old; n = 41) had all meals provided for 9 days with the same energy and macronutrient composition as their standard diet, but with starch substituted for sugar, yielding a final fructose content of 4% of total kilocalories. Metabolic assessments were performed before and after fructose restriction. Liver fat, VAT, and subcutaneous fat were determined by magnetic resonance spectroscopy and imaging. The fractional DNL area under the curve value was measured using stable isotope tracers and gas chromatography/mass spectrometry. Insulin kinetics were calculated from oral glucose tolerance tests. Paired analyses compared change from day 0 to day 10 within each child. Compared with baseline, on day 10, liver fat decreased from a median of 7.2% (interquartile range [IQR], 2.5%-14.8%) to 3.8% (IQR, 1.7%-15.5%) (P fructose restriction decreased liver fat, VAT, and DNL, and improved insulin kinetics in children with obesity. These findings support efforts to reduce sugar consumption. ClinicalTrials.gov Number: NCT01200043. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Statistical mechanics of cellular automata

International Nuclear Information System (INIS)

Wolfram, S.

1983-01-01

Cellular automata are used as simple mathematical models to investigate self-organization in statistical mechanics. A detailed analysis is given of ''elementary'' cellular automata consisting of a sequence of sites with values 0 or 1 on a line, with each site evolving deterministically in discrete time steps according to p definite rules involving the values of its nearest neighbors. With simple initial configurations, the cellular automata either tend to homogeneous states, or generate self-similar patterns with fractal dimensions approx. =1.59 or approx. =1.69. With ''random'' initial configurations, the irreversible character of the cellular automaton evolution leads to several self-organization phenomena. Statistical properties of the structures generated are found to lie in two universality classes, independent of the details of the initial state or the cellular automaton rules. More complicated cellular automata are briefly considered, and connections with dynamical systems theory and the formal theory of computation are discussed

A Mathematical Model for Cisplatin Cellular Pharmacodynamics

Directory of Open Access Journals (Sweden)

Ardith W. El-Kareh

2003-03-01

Full Text Available A simple theoretical model for the cellular pharmacodynamics of cisplatin is presented. The model, which takes into account the kinetics of cisplatin uptake by cells and the intracellular binding of the drug, can be used to predict the dependence of survival (relative to controls on the time course of extracellular exposure. Cellular pharmacokinetic parameters are derived from uptake data for human ovarian and head and neck cancer cell lines. Survival relative to controls is assumed to depend on the peak concentration of DNA-bound intracellular platinum. Model predictions agree well with published data on cisplatin cytotoxicity for three different cancer cell lines, over a wide range of exposure times. In comparison with previously published mathematical models for anticancer drug pharmacodynamics, the present model provides a better fit to experimental data sets including long exposure times (∼100 hours. The model provides a possible explanation for the fact that cell kill correlates well with area under the extracellular concentration-time curve in some data sets, but not in others. The model may be useful for optimizing delivery schedules and for the dosing of cisplatin for cancer therapy.

Wireless Cellular Mobile Communications

OpenAIRE

Zalud, V.

2002-01-01

In this article is briefly reviewed the history of wireless cellular mobile communications, examined the progress in current second generation (2G) cellular standards and discussed their migration to the third generation (3G). The European 2G cellular standard GSM and its evolution phases GPRS and EDGE are described somewhat in detail. The third generation standard UMTS taking up on GSM/GPRS core network and equipped with a new advanced access network on the basis of code division multiple ac...

MSAT and cellular hybrid networking

Science.gov (United States)

Baranowsky, Patrick W., II

Westinghouse Electric Corporation is developing both the Communications Ground Segment and the Series 1000 Mobile Phone for American Mobile Satellite Corporation's (AMSC's) Mobile Satellite (MSAT) system. The success of the voice services portion of this system depends, to some extent, upon the interoperability of the cellular network and the satellite communication circuit switched communication channels. This paper will describe the set of user-selectable cellular interoperable modes (cellular first/satellite second, etc.) provided by the Mobile Phone and described how they are implemented with the ground segment. Topics including roaming registration and cellular-to-satellite 'seamless' call handoff will be discussed, along with the relevant Interim Standard IS-41 Revision B Cellular Radiotelecommunications Intersystem Operations and IOS-553 Mobile Station - Land Station Compatibility Specification.

Control of human adenovirus type 5 gene expression by cellular Daxx/ATRX chromatin-associated complexes

DEFF Research Database (Denmark)

Schreiner, Sabrina; Bürck, Carolin; Glass, Mandy

2013-01-01

to interact with ATRX. To ensure efficient viral replication, Ad5 E1B-55K protein inhibits Daxx and targets ATRX for proteasomal degradation in cooperation with early region 4 open reading frame protein 6 and cellular components of a cullin-dependent E3-ubiquitin ligase. Our studies illustrate the importance...... is the targeting factor, leading to histone deacetylase recruitment, H3.3 deposition and transcriptional repression of cellular promoters. Despite recent findings on the fundamental importance of chromatin modification in host-cell gene regulation, it remains unclear whether adenovirus type 5 (Ad5) transcription...

Application of artificial intelligence (AI) methods for designing and analysis of reconfigurable cellular manufacturing system (RCMS)

CSIR Research Space (South Africa)

Xing, B

2009-12-01

Full Text Available This work focuses on the design and control of a novel hybrid manufacturing system: Reconfigurable Cellular Manufacturing System (RCMS) by using Artificial Intelligence (AI) approach. It is hybrid as it combines the advantages of Cellular...

Lysosomal Re-acidification Prevents Lysosphingolipid-Induced Lysosomal Impairment and Cellular Toxicity.

Directory of Open Access Journals (Sweden)

Christopher J Folts

2016-12-01

Full Text Available Neurodegenerative lysosomal storage disorders (LSDs are severe and untreatable, and mechanisms underlying cellular dysfunction are poorly understood. We found that toxic lipids relevant to three different LSDs disrupt multiple lysosomal and other cellular functions. Unbiased drug discovery revealed several structurally distinct protective compounds, approved for other uses, that prevent lysosomal and cellular toxicities of these lipids. Toxic lipids and protective agents show unexpected convergence on control of lysosomal pH and re-acidification as a critical component of toxicity and protection. In twitcher mice (a model of Krabbe disease [KD], a central nervous system (CNS-penetrant protective agent rescued myelin and oligodendrocyte (OL progenitors, improved motor behavior, and extended lifespan. Our studies reveal shared principles relevant to several LSDs, in which diverse cellular and biochemical disruptions appear to be secondary to disruption of lysosomal pH regulation by specific lipids. These studies also provide novel protective strategies that confer therapeutic benefits in a mouse model of a severe LSD.

Blood fatty acid patterns are associated with prostate cancer risk in a prospective nested case-control study.

Science.gov (United States)

Yang, Meng; Ayuningtyas, Azalea; Kenfield, Stacey A; Sesso, Howard D; Campos, Hannia; Ma, Jing; Stampfer, Meir J; Chavarro, Jorge E

2016-09-01

Circulating fatty acids are highly correlated with each other, and analyzing fatty acid patterns could better capture their interactions and their relation to prostate cancer. We aimed to assess the associations between data-derived blood fatty acid patterns and prostate cancer risk. We conducted a nested case-control study in the Physicians' Health Study. Fatty acids levels were measured in whole blood samples of 476 cases and their matched controls by age and smoking status. Fatty acid patterns were identified using principal component analysis. Conditional logistic regression was used to estimate odds ratio (OR) and 95 % confidence interval (CI). Two patterns explaining 40.9 % of total variation in blood fatty acid levels were identified. Pattern 1, which mainly reflects polyunsaturated fatty acid metabolism, was suggestively positively related to prostate cancer risk (ORquintile 5 vs. quintile 1 = 1.37, 95 % CI = 0.91-2.05, P trend = 0.07). Pattern 2, which largely reflects de novo lipogenesis, was significantly associated with higher prostate cancer risk (ORquintile5 vs. quintile1 = 1.63, 95 % CI = 1.04-2.55, P trend = 0.02). This association was similar across tumor stage, grade, clinical aggressiveness categories and follow-up time. The two patterns of fatty acids we identified were consistent with known interactions between fatty acid intake and metabolism. A pattern suggestive of higher activity in the de novo lipogenesis pathway was related to higher risk of prostate cancer.

Top-down cellular pyramids

Energy Technology Data Exchange (ETDEWEB)

Wu, A Y; Rosenfeld, A

1983-10-01

A cellular pyramid is an exponentially tapering stack of arrays of processors (cells), where each cell is connected to its neighbors (siblings) on its own level, to a parent on the level above, and to its children on the level below. It is shown that in some situations, if information flows top-down only, from fathers to sons, then a cellular pyramid may be no faster than a one-level cellular array; but it may be possible to use simpler cells in the pyramid case. 23 references.

Cellular decomposition in vikalloys

International Nuclear Information System (INIS)

Belyatskaya, I.S.; Vintajkin, E.Z.; Georgieva, I.Ya.; Golikov, V.A.; Udovenko, V.A.

1981-01-01

Austenite decomposition in Fe-Co-V and Fe-Co-V-Ni alloys at 475-600 deg C is investigated. The cellular decomposition in ternary alloys results in the formation of bcc (ordered) and fcc structures, and in quaternary alloys - bcc (ordered) and 12R structures. The cellular 12R structure results from the emergence of stacking faults in the fcc lattice with irregular spacing in four layers. The cellular decomposition results in a high-dispersion structure and magnetic properties approaching the level of well-known vikalloys [ru

Controlling major cellular processes of human mesenchymal stem cells using microwell structures.

Science.gov (United States)

Xu, Xun; Wang, Weiwei; Kratz, Karl; Fang, Liang; Li, Zhengdong; Kurtz, Andreas; Ma, Nan; Lendlein, Andreas

2014-12-01

Directing stem cells towards a desired location and function by utilizing the structural cues of biomaterials is a promising approach for inducing effective tissue regeneration. Here, the cellular response of human adipose-derived mesenchymal stem cells (hADSCs) to structural signals from microstructured substrates comprising arrays of square-shaped or round-shaped microwells is explored as a transitional model between 2D and 3D systems. Microwells with a side length/diameter of 50 μm show advantages over 10 μm and 25 μm microwells for accommodating hADSCs within single microwells rather than in the inter-microwell area. The cell morphologies are three-dimensionally modulated by the microwell structure due to differences in focal adhesion and consequent alterations of the cytoskeleton. In contrast to the substrate with 50 μm round-shaped microwells, the substrate with 50 μm square-shaped microwells promotes the proliferation and osteogenic differentiation potential of hADSCs but reduces the cell migration velocity and distance. Such microwell shape-dependent modulatory effects are highly associated with Rho/ROCK signaling. Following ROCK inhibition, the differences in migration, proliferation, and osteogenesis between cells on different substrates are diminished. These results highlight the possibility to control stem cell functions through the use of structured microwells combined with the manipulation of Rho/ROCK signaling. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Device-to-Device Underlay Cellular Networks with Uncertain Channel State Information

KAUST Repository

Memmi, Amen

2016-01-06

Device-to-Device (D2D) communications underlying the cellular infrastructure is a technology that has recently been proposed as a promising solution to enhance cellular network capabilities: It improves spectrum utilization, overall throughput and energy efficiency while enabling new peer-to-peer and location-based applications and services. However, interference is the major challenge since the same resources are shared by both systems. Therefore, interference management techniques are required to keep the interference under control. In this work, in order to mitigate interference, we consider centralized and distributed power control algorithms in a one-cell random network model. Differently from previous works, we are assuming that the channel state information (CSI) may be imperfect and include estimation errors. We evaluate how this uncertainty impacts performances.

Monoaminergic Control of Cellular Glucose Utilization by Glycogenolysis in Neocortex and Hippocampus.

Science.gov (United States)

DiNuzzo, Mauro; Giove, Federico; Maraviglia, Bruno; Mangia, Silvia

2015-12-01

Brainstem nuclei are the principal sites of monoamine (MA) innervation to major forebrain structures. In the cortical grey matter, increased secretion of MA neuromodulators occurs in response to a wealth of environmental and homeostatic challenges, whose onset is associated with rapid, preparatory changes in neural activity as well as with increases in energy metabolism. Blood-borne glucose is the main substrate for energy production in the brain. Once entered the tissue, interstitial glucose is equally accessible to neurons and astrocytes, the two cell types accounting for most of cellular volume and energy metabolism in neocortex and hippocampus. Astrocytes also store substantial amounts of glycogen, but non-stimulated glycogen turnover is very small. The rate of cellular glucose utilization in the brain is largely determined by hexokinase, which under basal conditions is more than 90 % inhibited by its product glucose-6-phosphate (Glc-6-P). During rapid increases in energy demand, glycogen is a primary candidate in modulating the intracellular level of Glc-6-P, which can occur only in astrocytes. Glycogenolysis can produce Glc-6-P at a rate higher than uptake and phosphorylation of glucose. MA neurotransmitter are released extrasinaptically by brainstem neurons projecting to neocortex and hippocampus, thus activating MA receptors located on both neuronal and astrocytic plasma membrane. Importantly, MAs are glycogenolytic agents and thus they are exquisitely suitable for regulation of astrocytic Glc-6-P concentration, upstream substrate flow through hexokinase and hence cellular glucose uptake. Conforming to such mechanism, Gerald A. Dienel and Nancy F. Cruz recently suggested that activation of noradrenergic locus coeruleus might reversibly block astrocytic glucose uptake by stimulating glycogenolysis in these cells, thereby anticipating the rise in glucose need by active neurons. In this paper, we further develop the idea that the whole monoaminergic system

Surface complement C3 fragments and cellular binding of microparticles in patients with SLE

DEFF Research Database (Denmark)

Winberg, Line Kjær; Nielsen, Claus Henrik; Jacobsen, Søren

2017-01-01

Objectives: To examine microparticles (MPs) from patients with SLE and healthy controls (HCs) by determining the cellular origin of the MPs, quantifying attached fragments of complement component 3 (C3) and assessing the ability of MPs to bind to circulating phagocytes and erythrocytes. These fea......Objectives: To examine microparticles (MPs) from patients with SLE and healthy controls (HCs) by determining the cellular origin of the MPs, quantifying attached fragments of complement component 3 (C3) and assessing the ability of MPs to bind to circulating phagocytes and erythrocytes...

Cellular automata analysis and applications

CERN Document Server

Hadeler, Karl-Peter

2017-01-01

This book focuses on a coherent representation of the main approaches to analyze the dynamics of cellular automata. Cellular automata are an inevitable tool in mathematical modeling. In contrast to classical modeling approaches as partial differential equations, cellular automata are straightforward to simulate but hard to analyze. In this book we present a review of approaches and theories that allow the reader to understand the behavior of cellular automata beyond simulations. The first part consists of an introduction of cellular automata on Cayley graphs, and their characterization via the fundamental Cutis-Hedlund-Lyndon theorems in the context of different topological concepts (Cantor, Besicovitch and Weyl topology). The second part focuses on classification results: What classification follows from topological concepts (Hurley classification), Lyapunov stability (Gilman classification), and the theory of formal languages and grammars (Kůrka classification). These classifications suggest to cluster cel...

3D-printing of lightweight cellular composites.

Science.gov (United States)

Compton, Brett G; Lewis, Jennifer A

2014-09-10

A new epoxy-based ink is reported, which enables 3D printing of lightweight cellular composites with controlled alignment of multiscale, high-aspectratio fiber reinforcement to create hierarchical structures inspired by balsa wood. Young's modulus values up to 10 times higher than existing commercially available 3D-printed polymers are attainable, while comparable strength values are maintained. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

MIMO Communication for Cellular Networks

CERN Document Server

Huang, Howard; Venkatesan, Sivarama

2012-01-01

As the theoretical foundations of multiple-antenna techniques evolve and as these multiple-input multiple-output (MIMO) techniques become essential for providing high data rates in wireless systems, there is a growing need to understand the performance limits of MIMO in practical networks. To address this need, MIMO Communication for Cellular Networks presents a systematic description of MIMO technology classes and a framework for MIMO system design that takes into account the essential physical-layer features of practical cellular networks. In contrast to works that focus on the theoretical performance of abstract MIMO channels, MIMO Communication for Cellular Networks emphasizes the practical performance of realistic MIMO systems. A unified set of system simulation results highlights relative performance gains of different MIMO techniques and provides insights into how best to use multiple antennas in cellular networks under various conditions. MIMO Communication for Cellular Networks describes single-user,...

On the Meta Distribution of Coverage Probability in Uplink Cellular Networks

KAUST Repository

Elsawy, Hesham; Alouini, Mohamed-Slim

2017-01-01

This letter studies the meta distribution of coverage probability (CP), within a stochastic geometry framework, for cellular uplink transmission with fractional path-loss inversion power control. Using the widely accepted Poisson point process (PPP

Chatty Mitochondria: Keeping Balance in Cellular Protein Homeostasis.

Science.gov (United States)

Topf, Ulrike; Wrobel, Lidia; Chacinska, Agnieszka

2016-08-01

Mitochondria are multifunctional cellular organelles that host many biochemical pathways including oxidative phosphorylation (OXPHOS). Defective mitochondria pose a threat to cellular homeostasis and compensatory responses exist to curtail the source of stress and/or its consequences. The mitochondrial proteome comprises proteins encoded by the nuclear and mitochondrial genomes. Disturbances in protein homeostasis may originate from mistargeting of nuclear encoded mitochondrial proteins. Defective protein import and accumulation of mistargeted proteins leads to stress that triggers translation alterations and proteasomal activation. These cytosolic pathways are complementary to the mitochondrial unfolded protein response (UPRmt) that aims to increase the capacity of protein quality control mechanisms inside mitochondria. They constitute putative targets for interventions aimed at increasing the fitness, stress resistance, and longevity of cells and organisms. Copyright © 2016 Elsevier Ltd. All rights reserved.

The CORVET complex: compositions, function, and impact on cellular behaviour

NARCIS (Netherlands)

Jonker, CTH

2016-01-01

The endolysosomal system is positioned on the crossroad of the intracellular and extracellular environment and is therefore crucial to regulate many cellular processes. Proper function of the endolysosomal system greatly depends on the concept of membrane identity; the controlled protein and lipid

Freeform inkjet printing of cellular structures with bifurcations.

Science.gov (United States)

Christensen, Kyle; Xu, Changxue; Chai, Wenxuan; Zhang, Zhengyi; Fu, Jianzhong; Huang, Yong

2015-05-01

Organ printing offers a great potential for the freeform layer-by-layer fabrication of three-dimensional (3D) living organs using cellular spheroids or bioinks as building blocks. Vascularization is often identified as a main technological barrier for building 3D organs. As such, the fabrication of 3D biological vascular trees is of great importance for the overall feasibility of the envisioned organ printing approach. In this study, vascular-like cellular structures are fabricated using a liquid support-based inkjet printing approach, which utilizes a calcium chloride solution as both a cross-linking agent and support material. This solution enables the freeform printing of spanning and overhang features by providing a buoyant force. A heuristic approach is implemented to compensate for the axially-varying deformation of horizontal tubular structures to achieve a uniform diameter along their axial directions. Vascular-like structures with both horizontal and vertical bifurcations have been successfully printed from sodium alginate only as well as mouse fibroblast-based alginate bioinks. The post-printing fibroblast cell viability of printed cellular tubes was found to be above 90% even after a 24 h incubation, considering the control effect. © 2014 Wiley Periodicals, Inc.

Cellular communications a comprehensive and practical guide

CERN Document Server

Tripathi, Nishith

2014-01-01

Even as newer cellular technologies and standards emerge, many of the fundamental principles and the components of the cellular network remain the same. Presenting a simple yet comprehensive view of cellular communications technologies, Cellular Communications provides an end-to-end perspective of cellular operations, ranging from physical layer details to call set-up and from the radio network to the core network. This self-contained source forpractitioners and students represents a comprehensive survey of the fundamentals of cellular communications and the landscape of commercially deployed

Receptor Oligomerization as a Process Modulating Cellular Semiotics

DEFF Research Database (Denmark)

Giorgi, Franco; Bruni, Luis Emilio; Maggio, Roberto

2010-01-01

be another level of quality control that may help maintaining GPCRs rather stable throughout evolution. We propose here receptor oligomerization to be a basic molecular mechanism controlling GPCRs redundancy in many different cell types, and the plasma membrane as the first hierarchical cell structure...... at which selective categorical sensing may occur. Categorical sensing can be seen as the cellular capacity for identifying and ordering complex patterns of mixed signals out of a contextual matrix, i.e., the recognition of meaningful patterns out of ubiquitous signals. In this context, redundancy...

Magnetohydrodynamics cellular automata

International Nuclear Information System (INIS)

Hatori, Tadatsugu.

1990-02-01

There has been a renewal of interest in cellular automata, partly because they give an architecture for a special purpose computer with parallel processing optimized to solve a particular problem. The lattice gas cellular automata are briefly surveyed, which are recently developed to solve partial differential equations such as hydrodynamics or magnetohydrodynamics. A new model is given in the present paper to implement the magnetic Lorentz force in a more deterministic and local procedure than the previous one. (author)

Magnetohydrodynamic cellular automata

Energy Technology Data Exchange (ETDEWEB)

Hatori, Tadatsugu [National Inst. for Fusion Science, Nagoya (Japan)

1990-03-01

There has been a renewal of interest in cellular automata, partly because they give an architecture for a special purpose computer with parallel processing optimized to solve a particular problem. The lattice gas cellular automata are briefly surveyed, which are recently developed to solve partial differential equations such as hydrodynamics or magnetohydrodynamics. A new model is given in the present paper to implement the magnetic Lorentz force in a more deterministic and local procedure than the previous one. (author).

Magnetohydrodynamic cellular automata

International Nuclear Information System (INIS)

Hatori, Tadatsugu

1990-01-01

There has been a renewal of interest in cellular automata, partly because they give an architecture for a special purpose computer with parallel processing optimized to solve a particular problem. The lattice gas cellular automata are briefly surveyed, which are recently developed to solve partial differential equations such as hydrodynamics or magnetohydrodynamics. A new model is given in the present paper to implement the magnetic Lorentz force in a more deterministic and local procedure than the previous one. (author)

Modeling cellular systems

CERN Document Server

Matthäus, Franziska; Pahle, Jürgen

2017-01-01

This contributed volume comprises research articles and reviews on topics connected to the mathematical modeling of cellular systems. These contributions cover signaling pathways, stochastic effects, cell motility and mechanics, pattern formation processes, as well as multi-scale approaches. All authors attended the workshop on "Modeling Cellular Systems" which took place in Heidelberg in October 2014. The target audience primarily comprises researchers and experts in the field, but the book may also be beneficial for graduate students.

Flaw tolerance vs. performance: A tradeoff in metallic glass cellular structures

International Nuclear Information System (INIS)

Chen, Wen; Liu, Ze; Robinson, Hannah Mae; Schroers, Jan

2014-01-01

Stochastic cellular structures are prevalent in nature and engineering materials alike. They are difficult to manipulate and study systematically and almost always contain imperfections. To design and characterize various degrees of imperfections in perfect periodic, stochastic and natural cellular structures, we fabricate a broad range of metallic glass cellular structures from perfectly periodic to highly stochastic by using a novel artificial microstructure approach based on thermoplastic replication of metallic glasses. For these cellular structures, precisely controlled imperfections are implemented and their effects on the mechanical response are evaluated. It is found that the mechanical performance of the periodic structures is generally superior to that of the stochastic structures. However, the stochastic structures experience a much higher tolerance to flaws than the periodic structure, especially in the plastic regime. The different flaw tolerance is explained by the stress distribution within the various structures, which leads to an overall 'strain-hardening' behavior of the stochastic structure compared to a 'strain-softening' behavior in the periodic structure. Our findings reveal how structure, 'strain-hardening' and flaw tolerance are microscopically related in structural materials

Cellular Angiofibroma of the Nasopharynx.

Science.gov (United States)

Erdur, Zülküf Burak; Yener, Haydar Murat; Yilmaz, Mehmet; Karaaltin, Ayşegül Batioğlu; Inan, Hakki Caner; Alaskarov, Elvin; Gozen, Emine Deniz

2017-11-01

Angiofibroma is a common tumor of the nasopharynx region but cellular type is extremely rare in head and neck. A 13-year-old boy presented with frequent epistaxis and nasal obstruction persisting for 6 months. According to the clinical symptoms and imaging studies juvenile angiofibroma was suspected. Following angiographic embolization total excision of the lesion by midfacial degloving approach was performed. Histological examination revealed that the tumor consisted of staghorn blood vessels and irregular fibrous stroma. Stellate fibroblasts with small pyknotic to large vesicular nuclei were seen in a highly cellular stroma. These findings identified cellular angiofibroma mimicking juvenile angiofibroma. This article is about a very rare patient of cellular angiofibroma of nasopharynx.

Tumour risk associated with use of cellular telephones or cordless desktop telephones

OpenAIRE

Hardell, Lennart; Mild, Kjell Hansson; Carlberg, Michael; Söderqvist, Fredrik

2006-01-01

Abstract Background The use of cellular and cordless telephones has increased dramatically during the last decade. There is concern of health problems such as malignant diseases due to microwave exposure during the use of these devices. The brain is the main target organ. Methods Since the second part of the 1990's we have performed six case-control studies on this topic encompassing use of both cellular and cordless phones as well as other exposures. Three of the studies concerned brain tumo...

A randomized controlled trial on the effectiveness of strength training on clinical and muscle cellular outcomes in patients with prostate cancer during androgen deprivation therapy: rationale and design

International Nuclear Information System (INIS)

Thorsen, Lene; Nilsen, Tormod S; Raastad, Truls; Courneya, Kerry S; Skovlund, Eva; Fosså, Sophie D

2012-01-01

Studies indicate that strength training has beneficial effects on clinical health outcomes in prostate cancer patients during androgen deprivation therapy. However, randomized controlled trials are needed to scientifically determine the effectiveness of strength training on the muscle cell level. Furthermore, close examination of the feasibility of a high-load strength training program is warranted. The Physical Exercise and Prostate Cancer (PEPC) trial is designed to determine the effectiveness of strength training on clinical and muscle cellular outcomes in non-metastatic prostate cancer patients after high-dose radiotherapy and during ongoing androgen deprivation therapy. Patients receiving androgen deprivation therapy for 9-36 months combined with external high-dose radiotherapy for locally advanced prostate cancer are randomized to an exercise intervention group that receives a 16 week high-load strength training program or a control group that is encouraged to maintain their habitual activity level. In both arms, androgen deprivation therapy is continued until the end of the intervention period. Clinical outcomes are body composition (lean body mass, bone mineral density and fat mass) measured by Dual-energy X-ray Absorptiometry, serological outcomes, physical functioning (muscle strength and cardio-respiratory fitness) assessed with physical tests and psycho-social functioning (mental health, fatigue and health-related quality of life) assessed by questionnaires. Muscle cellular outcomes are a) muscle fiber size b) regulators of muscle fiber size (number of myonuclei per muscle fiber, number of satellite cells per muscle fiber, number of satellite cells and myonuclei positive for androgen receptors and proteins involved in muscle protein degradation and muscle hypertrophy) and c) regulators of muscle fiber function such as proteins involved in cellular stress and mitochondrial function. Muscle cellular outcomes are measured on muscle cross sections and

47 CFR 22.923 - Cellular system configuration.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular system configuration. 22.923 Section... MOBILE SERVICES Cellular Radiotelephone Service § 22.923 Cellular system configuration. Mobile stations... directly or through cellular repeaters. Auxiliary test stations may communicate with base or mobile...

Enhancing the cellular uptake of Py–Im polyamides through next-generation aryl turns

OpenAIRE

Meier, Jordan L.; Montgomery, David C.; Dervan, Peter B.

2012-01-01

Pyrrole–imidazole (Py–Im) hairpin polyamides are a class of programmable, sequence-specific DNA binding oligomers capable of disrupting protein–DNA interactions and modulating gene expression in living cells. Methods to control the cellular uptake and nuclear localization of these compounds are essential to their application as molecular probes or therapeutic agents. Here, we explore modifications of the hairpin γ-aminobutyric acid turn unit as a means to enhance cellular uptake and biologica...

Perilipin 3 modulates specific lipogenic pathways in SZ95 sebocytes.

Science.gov (United States)

Camera, Emanuela; Dahlhoff, Maik; Ludovici, Matteo; Zouboulis, Christos C; Schneider, Marlon R

2014-10-01

Lipid droplets (LD) are dynamic organelles that manage cellular lipid synthesis, storage and retrieval. Although LD-associated proteins, including the perilipin family (PLIN1-PLIN5), are essential for these functions, they have been poorly characterized in sebocytes. Here, we employed siRNAs to downregulate PLIN3 in SZ95 sebaceous gland cells and evaluated the consequences in lipid accumulation by nile red staining and mass spectrometry. Nile red staining revealed that siRNA-mediated downregulation of PLIN3 significantly impaired linoleic acid-induced lipid accumulation in SZ95 sebocytes. Mass spectrometry revealed that PLIN3 was implicated in the metabolism of linoleic acid, a lipid source used in the build-up of triglycerides, among other acyl lipids. Furthermore, the expression of key enzymes of sebaceous lipogenesis was altered in PLIN3-deficient sebocytes, consistent with the changes observed in the neutral lipid abundance, suggesting that PLIN3 functions are intertwined with the lipogenic pathways implicated in sebaceous lipogenesis, such as desaturation and triglyceride synthesis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Recursive definition of global cellular-automata mappings

International Nuclear Information System (INIS)

Feldberg, R.; Knudsen, C.; Rasmussen, S.

1994-01-01

A method for a recursive definition of global cellular-automata mappings is presented. The method is based on a graphical representation of global cellular-automata mappings. For a given cellular-automaton rule the recursive algorithm defines the change of the global cellular-automaton mapping as the number of lattice sites is incremented. A proof of lattice size invariance of global cellular-automata mappings is derived from an approximation to the exact recursive definition. The recursive definitions are applied to calculate the fractal dimension of the set of reachable states and of the set of fixed points of cellular automata on an infinite lattice

Cellular oncogene expression following exposure of mice to γ-rays

International Nuclear Information System (INIS)

Anderson, A.; Woloschak, G.E.

1991-01-01

We examined the effects of total body exposure of BCF1 mice to γ-rays (300 cGy) in modulating expression of cellular oncogenes in both gut and liver tissues. We selected specific cellular oncogenes (c-fos, c-myc, c-src, and c-H-ras), based on their normal expression in liver and gut tissues from untreated mice. As early as 5 min. following whole body exposure of BCF1 mice to γ-rays we detected induction of mRNA specific for c-src and c-H-ras in both liver and gut tissues. c-fos RNA was slightly decreased in accumulation in gut but was unaffected in liver tissue from irradiated mice relative to untreated controls. c-myc mRNA accumulation was unaffected in all tissues examined. These experiments document that modulation of cellular oncogene expression can occur as an early event in tissues following irradiation and suggest that this modulation may play a role in radiation-induced carcinogenesis

13C NMR study of effects of fasting and diabetes on the metabolism of pyruvate in the tricarboxylic acid cycle and of the utilization of pyruvate and ethanol in lipogenesis in perfused rat liver

International Nuclear Information System (INIS)

Cohen, S.M.

1987-01-01

13 C NMR has been used to study the competition of pyruvate dehydrogenase with pyruvate carboxylase for entry of pyruvate into the tricarboxylic acid (TCA) cycle in perfused liver from streptozotocin-diabetic and normal donor rats. The relative proportion of pyruvate entering the TCA cycle by these two routes was estimated from the 13 C enrichments at the individual carbons of glutamate when [3- 13 C]alanine was the only exogenous substrate present. In this way, the proportion of pyruvate entering by the pyruvate dehydrogenase route relative to the pyruvate carboxylase route was determined to be 1:1.2 +/- 0.1 in liver from fed controls, 1:7.7 +/- 2 in liver from 24-fasted controls, and 1:2.6 +/- 0.3 in diabetic liver. Pursuant to this observation that conversion of pyruvate to acetyl coenzyme A (acetyl-CoA) was greatest in perfused liver from fed controls, the incorporation of 13 C label into fatty acids was monitored in this liver preparation. With the exception of the repeating methylene carbons, fatty acyl carbons labeled by [1- 13 C]acetyl-CoA (from [2- 13 C]pyruvate) gave rise to resonances distinguishable on the basis of chemical shift from those observed when label was introduced by [3- 13 C]alanine plus [2- 13 C]ethanol, which are converted to [2- 13 C]acetyl-CoA. Thus, measurement of 13 C enrichment at several specific sites in the fatty acyl chains in time-resolved spectra of perfused liver offers a novel way of monitoring the kinetics of the biosynthesis of fatty acids. In addition to obtaining the rate of lipogenesis, it was possible to distinguish the contributions of chain elongation from those of the de novo synthesis pathway and to estimate the average chain length of the 13 C-labeled fatty acids produced

Drug-induced activation of SREBP-controlled lipogenic gene expression in CNS-related cell lines: Marked differences between various antipsychotic drugs

Directory of Open Access Journals (Sweden)

Vik-Mo Audun O

2006-10-01

Full Text Available Abstract Background The etiology of schizophrenia is unknown, but neurodevelopmental disturbances, myelin- and oligodendrocyte abnormalities and synaptic dysfunction have been suggested as pathophysiological factors in this severe psychiatric disorder. Cholesterol is an essential component of myelin and has proved important for synapse formation. Recently, we demonstrated that the antipsychotic drugs clozapine and haloperidol stimulate lipogenic gene expression in cultured glioma cells through activation of the sterol regulatory element-binding protein (SREBP transcription factors. We here compare the action of chlorpromazine, haloperidol, clozapine, olanzapine, risperidone and ziprasidone on SREBP activation and SREBP-controlled gene expression (ACAT2, HMGCR, HMGCS1, FDPS, SC5DL, DHCR7, LDLR, FASN and SCD1 in four CNS-relevant human cell lines. Results There were marked differences in the ability of the antipsychotic drugs to activate the expression of SREBP target genes, with clozapine and chlorpromazine as the most potent stimulators in a context of therapeutically relevant concentrations. Glial-like cells (GaMg glioma and CCF-STTG1 astrocytoma cell lines displayed more pronounced drug-induced SREBP activation compared to the response in HCN2 human cortical neurons and SH-SY5Y neuroblastoma cells, indicating that antipsychotic-induced activation of lipogenesis is most prominent in glial cells. Conclusion Our present data show a marked variation in the ability of different antipsychotics to induce SREBP-controlled transcriptional activation of lipogenesis in cultured human CNS-relevant cells. We propose that this effect could be relevant for the therapeutic efficacy of some antipsychotic drugs.

Cellular senescence and organismal aging.

Science.gov (United States)

Jeyapalan, Jessie C; Sedivy, John M

2008-01-01

Cellular senescence, first observed and defined using in vitro cell culture studies, is an irreversible cell cycle arrest which can be triggered by a variety of factors. Emerging evidence suggests that cellular senescence acts as an in vivo tumor suppression mechanism by limiting aberrant proliferation. It has also been postulated that cellular senescence can occur independently of cancer and contribute to the physiological processes of normal organismal aging. Recent data have demonstrated the in vivo accumulation of senescent cells with advancing age. Some characteristics of senescent cells, such as the ability to modify their extracellular environment, could play a role in aging and age-related pathology. In this review, we examine current evidence that links cellular senescence and organismal aging.

Zeno's paradox in quantum cellular automata

Energy Technology Data Exchange (ETDEWEB)

Groessing, G [Atominst. der Oesterreichischen Universitaeten, Vienna (Austria); Zeilinger, A [Inst. fuer Experimentalphysik, Univ. Innsbruck (Austria)

1991-07-01

The effect of Zeno's paradox in quantum theory is demonstrated with the aid of quantum mechanical cellular automata. It is shown that the degree of non-unitarity of the cellular automaton evolution and the frequency of consecutive measurements of cellular automaton states are operationally indistinguishable. (orig.).

Zeno's paradox in quantum cellular automata

International Nuclear Information System (INIS)

Groessing, G.; Zeilinger, A.

1991-01-01

The effect of Zeno's paradox in quantum theory is demonstrated with the aid of quantum mechanical cellular automata. It is shown that the degree of non-unitarity of the cellular automaton evolution and the frequency of consecutive measurements of cellular automaton states are operationally indistinguishable. (orig.)

Electrostatic bio-manipulation for the modification of cellular functions

International Nuclear Information System (INIS)

Washizu, Masao

2013-01-01

The use of electrostatic field effects, including field-induced reversible-breakdown of the membrane and dielectrophoresis (DEP), in microfabricated structures are investigated. With the use of field constriction created by a micro-orifice whose diameter is smaller than the cells, controlled magnitude of pulsed voltage can be applied across the cell membrane regardless of the cell size, shape or orientation. As a result, the breakdown occurs reproducibly and with minimal invasiveness. The breakdown is used for two purposes, electroporation by which foreign substances can be fed into cells, and electrofusion which creates genetic and/or cytoplasmic mixture among two cells. When GFP plasmid is fed into MSC cell, the gene expression started within 2 hours, and finally observed in more than 50% of cells. For cell fusion, several ten percent fusion yield is achieved for most cell types, with the colony formation in several percents. Timing-controlled feeding foreign substances or mixing cellular contents, with high-yield and low-invasiveness, is expected to bring about a new technology for both genetic and epigenetic modifications of cellular functions, in such field as regenerative medicine.

47 CFR 90.672 - Unacceptable interference to non-cellular 800 MHz licensees from 800 MHz cellular systems or part...

Science.gov (United States)

2010-10-01

... 47 Telecommunication 5 2010-10-01 2010-10-01 false Unacceptable interference to non-cellular 800 MHz licensees from 800 MHz cellular systems or part 22 Cellular Radiotelephone systems, and within the... Procedures and Process-Unacceptable Interference § 90.672 Unacceptable interference to non-cellular 800 MHz...

Transcellular tunnel dynamics: Control of cellular dewetting by actomyosin contractility and I-BAR proteins.

Science.gov (United States)

Lemichez, Emmanuel; Gonzalez-Rodriguez, David; Bassereau, Patricia; Brochard-Wyart, Françoise

2013-03-01

Dewetting is the spontaneous withdrawal of a liquid film from a non-wettable surface by nucleation and growth of dry patches. Two recent reports now propose that the principles of dewetting explain the physical phenomena underpinning the opening of transendothelial cell macroaperture (TEM) tunnels, referred to as cellular dewetting. This was discovered by studying a group of bacterial toxins endowed with the property of corrupting actomyosin cytoskeleton contractility. For both liquid and cellular dewetting, the growth of holes is governed by a competition between surface forces and line tension. We also discuss how the dynamics of TEM opening and closure represent remarkable systems to investigate actin cytoskeleton regulation by sensors of plasma membrane curvature and investigate the impact on membrane tension and the role of TEM in vascular dysfunctions. Copyright © 2013 Soçiété Française des Microscopies and Soçiété de Biologie Cellulaire de France.

The effects of cellular glutathione elevation on the oxygen enhancement ratio

International Nuclear Information System (INIS)

Mitchell, J.B.; Russo, A.

1984-01-01

It has recently been demonstrated for Chinese hamster and human A549 cells that depletion of cellular glutathione (GSH) by buthionine sulfoximine sensitizes both aerated and hypoxic cells to X-rays. While the extent of sensitization was minimal for both conditions, there was no overall reduction in the oxygen enhancement ratio (OER). The authors have investigated the effect of cellular GSH elevation on the OER by treating cells for 2 hours with 10 mM L-2-oxothiazolidine-4-carboxylate (OTZ) or face 24 hours with 0.06 mM cobalt chloride (CoCl/sub 2/) in complete medium. These treatments resulted in cellular concentrations of GSH to approximately 150-250% for OTZ and 150-300% for CoCl/sub 2/ when compared to controls. X-ray survival curves were determined following these treatments for aerated and hypoxic conditions. Hypoxia was induced by metabolic utilization of oxygen at high cell densities (10/sup 8//ml) in glass syringes. For both methods of GSH elevation, there was no protection observed for either aerated or hypoxic cells and consequently no change in the OER when compared to controls. These data are discussed in the context of the radical-scavenging hypothesis involving chemical repair following X-rays of compounds such as GSH

Cellular Therapeutics for Heart Failure: Focus on Mesenchymal Stem Cells

Directory of Open Access Journals (Sweden)

Amitabh C. Pandey

2017-01-01

Full Text Available Resulting from a various etiologies, the most notable remains ischemia; heart failure (HF manifests as the common end pathway of many cardiovascular processes and remains among the top causes for hospitalization and a major cause of morbidity and mortality worldwide. Current pharmacologic treatment for HF utilizes pharmacologic agents to control symptoms and slow further deterioration; however, on a cellular level, in a patient with progressive disease, fibrosis and cardiac remodeling can continue leading to end-stage heart failure. Cellular therapeutics have risen as the new hope for an improvement in the treatment of HF. Mesenchymal stem cells (MSCs have gained popularity given their propensity of promoting endogenous cellular repair of a myriad of disease processes via paracrine signaling through expression of various cytokines, chemokines, and adhesion molecules resulting in activation of signal transduction pathways. While the exact mechanism remains to be completely elucidated, this remains the primary mechanism identified to date. Recently, MSCs have been incorporated as the central focus in clinical trials investigating the role how MSCs can play in the treatment of HF. In this review, we focus on the characteristics of MSCs that give them a distinct edge as cellular therapeutics and present results of clinical trials investigating MSCs in the setting of ischemic HF.

Origami interleaved tube cellular materials

International Nuclear Information System (INIS)

Cheung, Kenneth C; Tachi, Tomohiro; Calisch, Sam; Miura, Koryo

2014-01-01

A novel origami cellular material based on a deployable cellular origami structure is described. The structure is bi-directionally flat-foldable in two orthogonal (x and y) directions and is relatively stiff in the third orthogonal (z) direction. While such mechanical orthotropicity is well known in cellular materials with extruded two dimensional geometry, the interleaved tube geometry presented here consists of two orthogonal axes of interleaved tubes with high interfacial surface area and relative volume that changes with fold-state. In addition, the foldability still allows for fabrication by a flat lamination process, similar to methods used for conventional expanded two dimensional cellular materials. This article presents the geometric characteristics of the structure together with corresponding kinematic and mechanical modeling, explaining the orthotropic elastic behavior of the structure with classical dimensional scaling analysis. (paper)

Origami interleaved tube cellular materials

Science.gov (United States)

Cheung, Kenneth C.; Tachi, Tomohiro; Calisch, Sam; Miura, Koryo

2014-09-01

A novel origami cellular material based on a deployable cellular origami structure is described. The structure is bi-directionally flat-foldable in two orthogonal (x and y) directions and is relatively stiff in the third orthogonal (z) direction. While such mechanical orthotropicity is well known in cellular materials with extruded two dimensional geometry, the interleaved tube geometry presented here consists of two orthogonal axes of interleaved tubes with high interfacial surface area and relative volume that changes with fold-state. In addition, the foldability still allows for fabrication by a flat lamination process, similar to methods used for conventional expanded two dimensional cellular materials. This article presents the geometric characteristics of the structure together with corresponding kinematic and mechanical modeling, explaining the orthotropic elastic behavior of the structure with classical dimensional scaling analysis.

Estimating cellular network performance during hurricanes

International Nuclear Information System (INIS)

Booker, Graham; Torres, Jacob; Guikema, Seth; Sprintson, Alex; Brumbelow, Kelly

2010-01-01

Cellular networks serve a critical role during and immediately after a hurricane, allowing citizens to contact emergency services when land-line communication is lost and serving as a backup communication channel for emergency responders. However, due to their ubiquitous deployment and limited design for extreme loading events, basic network elements, such as cellular towers and antennas are prone to failures during adverse weather conditions such as hurricanes. Accordingly, a systematic and computationally feasible approach is required for assessing and improving the reliability of cellular networks during hurricanes. In this paper we develop a new multi-disciplinary approach to efficiently and accurately assess cellular network reliability during hurricanes. We show how the performance of a cellular network during and immediately after future hurricanes can be estimated based on a combination of hurricane wind field models, structural reliability analysis, Monte Carlo simulation, and cellular network models and simulation tools. We then demonstrate the use of this approach for assessing the improvement in system reliability that can be achieved with discrete topological changes in the system. Our results suggest that adding redundancy, particularly through a mesh topology or through the addition of an optical fiber ring around the perimeter of the system can be an effective way to significantly increase the reliability of some cellular systems during hurricanes.

The cellular memory disc of reprogrammed cells.

Science.gov (United States)

Anjamrooz, Seyed Hadi

2013-04-01

The crucial facts underlying the low efficiency of cellular reprogramming are poorly understood. Cellular reprogramming occurs in nuclear transfer, induced pluripotent stem cell (iPSC) formation, cell fusion, and lineage-switching experiments. Despite these advances, there are three fundamental problems to be addressed: (1) the majority of cells cannot be reprogrammed, (2) the efficiency of reprogramming cells is usually low, and (3) the reprogrammed cells developed from a patient's own cells activate immune responses. These shortcomings present major obstacles for using reprogramming approaches in customised cell therapy. In this Perspective, the author synthesises past and present observations in the field of cellular reprogramming to propose a theoretical picture of the cellular memory disc. The current hypothesis is that all cells undergo an endogenous and exogenous holographic memorisation such that parts of the cellular memory dramatically decrease the efficiency of reprogramming cells, act like a barrier against reprogramming in the majority of cells, and activate immune responses. Accordingly, the focus of this review is mainly to describe the cellular memory disc (CMD). Based on the present theory, cellular memory includes three parts: a reprogramming-resistance memory (RRM), a switch-promoting memory (SPM) and a culture-induced memory (CIM). The cellular memory arises genetically, epigenetically and non-genetically and affects cellular behaviours. [corrected].

Blood cell gene expression associated with cellular stress defense is modulated by antioxidant-rich food in a randomised controlled clinical trial of male smokers.

Science.gov (United States)

Bøhn, Siv K; Myhrstad, Mari C; Thoresen, Magne; Holden, Marit; Karlsen, Anette; Tunheim, Siv Haugen; Erlund, Iris; Svendsen, Mette; Seljeflot, Ingebjørg; Moskaug, Jan O; Duttaroy, Asim K; Laake, Petter; Arnesen, Harald; Tonstad, Serena; Collins, Andrew; Drevon, Christan A; Blomhoff, Rune

2010-09-16

Plant-based diets rich in fruit and vegetables can prevent development of several chronic age-related diseases. However, the mechanisms behind this protective effect are not elucidated. We have tested the hypothesis that intake of antioxidant-rich foods can affect groups of genes associated with cellular stress defence in human blood cells. NCT00520819 http://clinicaltrials.gov. In an 8-week dietary intervention study, 102 healthy male smokers were randomised to either a diet rich in various antioxidant-rich foods, a kiwifruit diet (three kiwifruits/d added to the regular diet) or a control group. Blood cell gene expression profiles were obtained from 10 randomly selected individuals of each group. Diet-induced changes on gene expression were compared to controls using a novel application of the gene set enrichment analysis (GSEA) on transcription profiles obtained using Affymetrix HG-U133-Plus 2.0 whole genome arrays. Changes were observed in the blood cell gene expression profiles in both intervention groups when compared to the control group. Groups of genes involved in regulation of cellular stress defence, such as DNA repair, apoptosis and hypoxia, were significantly upregulated (GSEA, FDR q-values < 5%) by both diets compared to the control group. Genes with common regulatory motifs for aryl hydrocarbon receptor (AhR) and AhR nuclear translocator (AhR/ARNT) were upregulated by both interventions (FDR q-values < 5%). Plasma antioxidant biomarkers (polyphenols/carotenoids) increased in both groups. The observed changes in the blood cell gene expression profiles suggest that the beneficial effects of a plant-based diet on human health may be mediated through optimization of defence processes.

Cosserat modeling of cellular solids

NARCIS (Netherlands)

Onck, P.R.

Cellular solids inherit their macroscopic mechanical properties directly from the cellular microstructure. However, the characteristic material length scale is often not small compared to macroscopic dimensions, which limits the applicability of classical continuum-type constitutive models. Cosserat

Cellular toxicity of calf blood extract on human corneal epithelial cells in vitro.

Science.gov (United States)

Park, Young Min; Kim, Su Jin; Han, Young Sang; Lee, Jong Soo

2015-01-01

To investigate the biologic effects of the calf blood extract on corneal epithelial cells in vitro. The effects on corneal epithelial cells were evaluated after 1, 4, 12, and 24 h of exposure to various concentrations of calf blood extract (3, 5, 8 and 16%). The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay was performed to measure levels of cellular metabolic activity. The lactate dehydrogenase (LDH) assay was performed to determine the extent of cellular damage. Cellular morphology was examined using phase-contrast microscopy. The scratch wound assay was performed to quantify the migration of corneal epithelial cells. At the 3 and 5% concentrations of calf blood extract, MTT values were similar to those observed in the control group. However, at a concentration of 8 and 16%, cellular metabolic activity was significantly decreased after 4 h of exposure to calf blood extract. After 12 h of exposure to 8 and 16% concentrations of calf blood extract, LDH activity and cellular morphological damage to the corneal epithelial cells were significantly increased. There was no evidence of cellular migration after 12 h exposure to 5% or higher concentration of calf blood extract because of cellular toxicity. Compared with normal corneal epithelial cells, the cellular activity was decreased, and toxicity was increased after over 12 h of exposure to more than 5% concentration of calf blood extract. Further clinical studies will be necessary to determine the optimal concentration and exposure time for the topical application of eye drops containing calf blood extract.

Cellular response to DNA damage. Link between p53 and DNA-PK

International Nuclear Information System (INIS)

Salles-Passador, I.; Fotedar, R.; Fotedar, A.

1999-01-01

Cells which lack DNA-activated protein kinase (DNA-PK) are very susceptible to ionizing radiation and display an inability to repair double-strand DNA breaks. DNA-PK is a member of a protein kinase family that includes ATR and ATM which have strong homology in their carboxy-terminal kinase domain with Pl-3 kinase. ATM has been proposed to act upstream of p53 in cellular response to ionizing radiation. DNA-PK may similarly interact with p53 in cellular growth control and in mediation of the response to ionizing radiation. (author)

A Compact Synchronous Cellular Model of Nonlinear Calcium Dynamics: Simulation and FPGA Synthesis Results.

Science.gov (United States)

Soleimani, Hamid; Drakakis, Emmanuel M

2017-06-01

Recent studies have demonstrated that calcium is a widespread intracellular ion that controls a wide range of temporal dynamics in the mammalian body. The simulation and validation of such studies using experimental data would benefit from a fast large scale simulation and modelling tool. This paper presents a compact and fully reconfigurable cellular calcium model capable of mimicking Hopf bifurcation phenomenon and various nonlinear responses of the biological calcium dynamics. The proposed cellular model is synthesized on a digital platform for a single unit and a network model. Hardware synthesis, physical implementation on FPGA, and theoretical analysis confirm that the proposed cellular model can mimic the biological calcium behaviors with considerably low hardware overhead. The approach has the potential to speed up large-scale simulations of slow intracellular dynamics by sharing more cellular units in real-time. To this end, various networks constructed by pipelining 10 k to 40 k cellular calcium units are compared with an equivalent simulation run on a standard PC workstation. Results show that the cellular hardware model is, on average, 83 times faster than the CPU version.

Recursive definition of global cellular-automata mappings

DEFF Research Database (Denmark)

Feldberg, Rasmus; Knudsen, Carsten; Rasmussen, Steen

1994-01-01

A method for a recursive definition of global cellular-automata mappings is presented. The method is based on a graphical representation of global cellular-automata mappings. For a given cellular-automaton rule the recursive algorithm defines the change of the global cellular-automaton mapping...... as the number of lattice sites is incremented. A proof of lattice size invariance of global cellular-automata mappings is derived from an approximation to the exact recursive definition. The recursive definitions are applied to calculate the fractal dimension of the set of reachable states and of the set...

A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols

Directory of Open Access Journals (Sweden)

Aamir Shahzad

2016-06-01

Full Text Available Substantial changes have occurred in the Information Technology (IT sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network.

A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols.

Science.gov (United States)

Shahzad, Aamir; Landry, René; Lee, Malrey; Xiong, Naixue; Lee, Jongho; Lee, Changhoon

2016-06-14

Substantial changes have occurred in the Information Technology (IT) sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA) server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network.

A New Cellular Architecture for Information Retrieval from Sensor Networks through Embedded Service and Security Protocols

Science.gov (United States)

Shahzad, Aamir; Landry, René; Lee, Malrey; Xiong, Naixue; Lee, Jongho; Lee, Changhoon

2016-01-01

Substantial changes have occurred in the Information Technology (IT) sectors and with these changes, the demand for remote access to field sensor information has increased. This allows visualization, monitoring, and control through various electronic devices, such as laptops, tablets, i-Pads, PCs, and cellular phones. The smart phone is considered as a more reliable, faster and efficient device to access and monitor industrial systems and their corresponding information interfaces anywhere and anytime. This study describes the deployment of a protocol whereby industrial system information can be securely accessed by cellular phones via a Supervisory Control And Data Acquisition (SCADA) server. To achieve the study goals, proprietary protocol interconnectivity with non-proprietary protocols and the usage of interconnectivity services are considered in detail. They support the visualization of the SCADA system information, and the related operations through smart phones. The intelligent sensors are configured and designated to process real information via cellular phones by employing information exchange services between the proprietary protocol and non-proprietary protocols. SCADA cellular access raises the issue of security flaws. For these challenges, a cryptography-based security method is considered and deployed, and it could be considered as a part of a proprietary protocol. Subsequently, transmission flows from the smart phones through a cellular network. PMID:27314351

Ischemia-induced glomerular parietal epithelial cells hyperplasia: Commonly misdiagnosed cellular crescent in renal biopsy.

Science.gov (United States)

Zeng, Yeting; Wang, Xinrui; Xie, Feilai; Zheng, Zhiyong

2017-08-01

Ischemic pseudo-cellular crescent (IPCC) that is induced by ischemia and composed of hyperplastic glomerular parietal epithelial cells resembles cellular crescent. In this study, we aimed to assess the clinical and pathological features of IPCC in renal biopsy to avoid over-diagnosis and to determine the diagnostic basis. 4 IPCC cases diagnosed over a 4-year period (2012-2015) were evaluated for the study. Meanwhile, 5 cases of ANCA-associated glomerulonephritis and 5 cases of lupus nephritis (LN) were selected as control. Appropriate clinical data, morphology, and immunohistochemical features of all cases were retrieved. Results showed that the basement membrane of glomerulus with IPCC appeared as a concentric twisted ball, and glomerular cells of the lesion were reduced even entirely absent, and the adjacent afferent arterioles showed sclerosis or luminal stenosis. Furthermore, immune globulin deposition, vasculitis, and fibrinous exudate have not been observed in IPCC. While the cellular crescents showed diverse characteristics in both morphology and immunostaining in the control group. Therefore, these results indicated that IPCC is a sort of ischemic reactive hyperplasia and associated with sclerosis, stenosis, or obstruction of adjacent afferent arterioles, which is clearly different from cellular crescents result from glomerulonephritis. Copyright © 2017 Elsevier GmbH. All rights reserved.

Evaluation of Structural Cellular Glass

Science.gov (United States)

Adams, M. A.; Zwissler, J. G.

1984-01-01

Preliminary design information presented. First report discusses state of structural-cellular-glass programs as of June 1979. Second report gives further details of program to develop improved cellular glasses and to characterize properties of glasses and commercially available materials.

Selective transcription and cellular proliferation induced by PDGF require histone deacetylase activity

International Nuclear Information System (INIS)

Catania, Annunziata; Iavarone, Carlo; Carlomagno, Stella M.; Chiariello, Mario

2006-01-01

Histone deacetylases (HDACs) are key regulatory enzymes involved in the control of gene expression and their inhibition by specific drugs has been widely correlated to cell cycle arrest, terminal differentiation, and apoptosis. Here, we investigated whether HDAC activity was required for PDGF-dependent signal transduction and cellular proliferation. Exposure of PDGF-stimulated NIH3T3 fibroblasts to the HDAC inhibitor trichostatin A (TSA) potently repressed the expression of a group of genes correlated to PDGF-dependent cellular growth and pro-survival activity. Moreover, we show that TSA interfered with STAT3-dependent transcriptional activity induced by PDGF. Still, neither phosphorylation nor nuclear translocation and DNA-binding in vitro and in vivo of STAT3 were affected by using TSA to interfere with PDGF stimulation. Finally, TSA treatment resulted in the suppression of PDGF-dependent cellular proliferation without affecting cellular survival of NIH3T3 cells. Our data indicate that inhibition of HDAC activity antagonizes the mitogenic effect of PDGF, suggesting that these drugs may specifically act on the expression of STAT-dependent, PDGF-responsive genes

Epigenetics and Cellular Metabolism

OpenAIRE

Wenyi Xu; Fengzhong Wang; Zhongsheng Yu; Fengjiao Xin

2016-01-01

Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc.) is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the proce...

ARGINASE 2 DEFICIENCY RESULTS IN SPONTANEOUS STEATOHEPATITIS: A NOVEL LINK BETWEEN INNATE IMMUNE ACTIVATION AND HEPATIC DE NOVO LIPOGENESIS

Science.gov (United States)

Navarro, Laura A.; Wree, Alexander; Povero, Davide; Berk, Michael P.; Eguchi, Akiko; Ghosh, Sudakshina; Papouchado, Bettina G.; Erzurum, Serpil C.; Feldstein, Ariel E.

2016-01-01

BACKGROUND & AIMS Innate immune activation has been postulated as a central mechanism for disease progression from hepatic steatosis to steatohepatitis in obesity-related fatty liver disease. Arginase 2 competes with inducible nitric oxide synthase (iNOS) for its substrate and the balance between these two enzymes plays a crucial role in regulating immune responses and macrophage activation. Our aim was to test the hypothesis that arginase 2 deficiency in mice favors progression from isolated hepatic steatosis, induced by high fat feeding to steatohepatitis. METHODS Arginase 2-knockout (Arg2−/−) mice were studied for changes in liver histology and metabolic phenotype at baseline and after a short term course (7 week) feeding with a high fat (HFAT) diet. In additional experiments, Arg2−/− mice received tail vein injections of liposome-encapsulated clodronate (CLOD) over a three-week period to selectively deplete liver macrophages. RESULTS Unexpectedly, Arg2−/− mice showed profound changes in their livers at baseline characterized by significant steatosis as demonstrated with histological and biochemical analysis. These changes were independent of systemic metabolic parameters and associated with marked increase mRNA levels of genes involved in hepatic de novo lipogenesis. Liver injury and inflammation were present with elevated serum ALT, marked infiltration of F4/80 positive cells, and increased mRNA levels of inflammatory genes. HFAT feeding exacerbated these changes. Macrophage depletion after CLOD injection significantly attenuated lipid deposition and normalized lipogenic mRNA profile of livers from Arg2−/− mice. CONCLUSIONS This study identifies arginase 2 as novel link between innate immune responses, hepatic lipid deposition, and liver injury. PMID:25234945

Inside-out signaling promotes dynamic changes in the carcinoembryonic antigen-related cellular adhesion molecule 1 (CEACAM1) oligomeric state to control its cell adhesion properties.

Science.gov (United States)

Patel, Prerna C; Lee, Hannah S W; Ming, Aaron Y K; Rath, Arianna; Deber, Charles M; Yip, Christopher M; Rocheleau, Jonathan V; Gray-Owen, Scott D

2013-10-11

Cell-cell contacts are fundamental to multicellular organisms and are subject to exquisite levels of control. The carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) can engage in both cis-homophilic (parallel) oligomerization and trans-homophilic (anti-parallel) binding. In this study, we establish that the CEACAM1 transmembrane domain has a propensity to form cis-dimers via the transmembrane-embedded (432)GXXXG(436) motif and that this basal state is overcome when activated calmodulin binds to the CEACAM1 cytoplasmic domain. Although mutation of the (432)GXXXG(436) motif reduced CEACAM1 oligomerization, it did not affect surface localization of the receptor or influence CEACAM1-dependent cellular invasion by the pathogenic Neisseria. The mutation did, however, have a striking effect on CEACAM1-dependent cellular aggregation, increasing both the kinetics of cell-cell association and the size of cellular aggregates formed. CEACAM1 association with tyrosine kinase c-Src and tyrosine phosphatases SHP-1 and SHP-2 was not affected by the (432)GXXXG(436) mutation, consistent with their association with the monomeric form of wild type CEACAM1. Collectively, our results establish that a dynamic oligomer-to-monomer shift in surface-expressed CEACAM1 facilitates trans-homophilic binding and downstream effector signaling.

Research advances in cellular immunotherapy for primary hepatocellular carcinoma

Directory of Open Access Journals (Sweden)

ZHANG Ye

2014-09-01

Full Text Available The present therapy for primary hepatocellular carcinoma (HCC consists of surgery as well as local radiotherapy and chemotherapy. However, the majority of patients are susceptible to recurrence after comprehensive treatment, and the overall treatment outcome is not ideal due to the lack of effective drugs and strategies. Increasing evidence has demonstrated that the immune system is closely related to the development, progression, metastasis, and recurrence of HCC. Thus, immune therapy, especially cellular immunotherapy, could regulate immune function and induce specific antitumor immunity to achieve the goal of controlling HCC and reducing its recurrence and metastasis, which has become an essential part in the comprehensive treatment of HCC. The findings in preclinical and clinical studies on cellular immunotherapy for HCC data are reviewed, and the current problems are discussed.

Cellular commitment in the developing cerebellum

Science.gov (United States)

Marzban, Hassan; Del Bigio, Marc R.; Alizadeh, Javad; Ghavami, Saeid; Zachariah, Robby M.; Rastegar, Mojgan

2014-01-01

The mammalian cerebellum is located in the posterior cranial fossa and is critical for motor coordination and non-motor functions including cognitive and emotional processes. The anatomical structure of cerebellum is distinct with a three-layered cortex. During development, neurogenesis and fate decisions of cerebellar primordium cells are orchestrated through tightly controlled molecular events involving multiple genetic pathways. In this review, we will highlight the anatomical structure of human and mouse cerebellum, the cellular composition of developing cerebellum, and the underlying gene expression programs involved in cell fate commitments in the cerebellum. A critical evaluation of the cell death literature suggests that apoptosis occurs in ~5% of cerebellar cells, most shortly after mitosis. Apoptosis and cellular autophagy likely play significant roles in cerebellar development, we provide a comprehensive discussion of their role in cerebellar development and organization. We also address the possible function of unfolded protein response in regulation of cerebellar neurogenesis. We discuss recent advancements in understanding the epigenetic signature of cerebellar compartments and possible connections between DNA methylation, microRNAs and cerebellar neurodegeneration. Finally, we discuss genetic diseases associated with cerebellar dysfunction and their role in the aging cerebellum. PMID:25628535

Cellular Commitment in the Developing Cerebellum

Directory of Open Access Journals (Sweden)

Hassan eMarzban

2015-01-01

Full Text Available The mammalian cerebellum is located in the posterior cranial fossa and is critical for motor coordination and non-motor functions including cognitive and emotional processes. The anatomical structure of cerebellum is distinct with a three-layered cortex. During development, neurogenesis and fate decisions of cerebellar primordium cells are orchestrated through tightly controlled molecular events involving multiple genetic pathways. In this review, we will highlight the anatomical structure of human and mouse cerebellum, the cellular composition of developing cerebellum, and the underlying gene expression programs involved in cell fate commitments in the cerebellum. A critical evaluation of the cell death literature suggests that apoptosis occurs in ~5% of cerebellar cells, most shortly after mitosis. Apoptosis and cellular autophagy likely play significant roles in cerebellar development, we provide a comprehensive discussion of their role in cerebellar development and organization. We also address the possible function of unfolded protein response in regulation of cerebellar neurogenesis. We discuss recent advancements in understanding the epigenetic signature of cerebellar compartments and possible connections between DNA methylation, microRNAs and cerebellar neurodegeneration. Finally, we then discuss genetic diseases associated with cerebellar dysfunction and their role in the aging cerebellum.

Modeling the mechanics of cancer: effect of changes in cellular and extra-cellular mechanical properties.

Science.gov (United States)

Katira, Parag; Bonnecaze, Roger T; Zaman, Muhammad H

2013-01-01

Malignant transformation, though primarily driven by genetic mutations in cells, is also accompanied by specific changes in cellular and extra-cellular mechanical properties such as stiffness and adhesivity. As the transformed cells grow into tumors, they interact with their surroundings via physical contacts and the application of forces. These forces can lead to changes in the mechanical regulation of cell fate based on the mechanical properties of the cells and their surrounding environment. A comprehensive understanding of cancer progression requires the study of how specific changes in mechanical properties influences collective cell behavior during tumor growth and metastasis. Here we review some key results from computational models describing the effect of changes in cellular and extra-cellular mechanical properties and identify mechanistic pathways for cancer progression that can be targeted for the prediction, treatment, and prevention of cancer.

Multiscale evaluation of cellular adhesion alteration and cytoskeleton remodeling by magnetic bead twisting.

Science.gov (United States)

Isabey, Daniel; Pelle, Gabriel; André Dias, Sofia; Bottier, Mathieu; Nguyen, Ngoc-Minh; Filoche, Marcel; Louis, Bruno

2016-08-01

Cellular adhesion forces depend on local biological conditions meaning that adhesion characterization must be performed while preserving cellular integrity. We presently postulate that magnetic bead twisting provides an appropriate stress, i.e., basically a clamp, for assessment in living cells of both cellular adhesion and mechanical properties of the cytoskeleton. A global dissociation rate obeying a Bell-type model was used to determine the natural dissociation rate ([Formula: see text]) and a reference stress ([Formula: see text]). These adhesion parameters were determined in parallel to the mechanical properties for a variety of biological conditions in which either adhesion or cytoskeleton was selectively weakened or strengthened by changing successively ligand concentration, actin polymerization level (by treating with cytochalasin D), level of exerted stress (by increasing magnetic torque), and cell environment (by using rigid and soft 3D matrices). On the whole, this multiscale evaluation of the cellular and molecular responses to a controlled stress reveals an evolution which is consistent with stochastic multiple bond theories and with literature results obtained with other molecular techniques. Present results confirm the validity of the proposed bead-twisting approach for its capability to probe cellular and molecular responses in a variety of biological conditions.

Cellular Stress Response to Engineered Nanoparticles: Effect of Size, Surface Coating, and Cellular Uptake

Science.gov (United States)

CELLULAR STRESS RESPONSE TO ENGINEERED NANOPARTICLES: EFFECT OF SIZE, SURFACE COATING, AND CELLULAR UPTAKE RY Prasad 1, JK McGee2, MG Killius1 D Ackerman2, CF Blackman2 DM DeMarini2 , SO Simmons2 1 Student Services Contractor, US EPA, RTP, NC 2 US EPA, RTP, NC The num...

Pan-neuronal calcium imaging with cellular resolution in freely swimming zebrafish.

Science.gov (United States)

Kim, Dal Hyung; Kim, Jungsoo; Marques, João C; Grama, Abhinav; Hildebrand, David G C; Gu, Wenchao; Li, Jennifer M; Robson, Drew N

2017-11-01

Calcium imaging with cellular resolution typically requires an animal to be tethered under a microscope, which substantially restricts the range of behaviors that can be studied. To expand the behavioral repertoire amenable to imaging, we have developed a tracking microscope that enables whole-brain calcium imaging with cellular resolution in freely swimming larval zebrafish. This microscope uses infrared imaging to track a target animal in a behavior arena. On the basis of the predicted trajectory of the animal, we applied optimal control theory to a motorized stage system to cancel brain motion in three dimensions. We combined this motion-cancellation system with differential illumination focal filtering, a variant of HiLo microscopy, which enabled us to image the brain of a freely swimming larval zebrafish for more than an hour. This work expands the repertoire of natural behaviors that can be studied with cellular-resolution calcium imaging to potentially include spatial navigation, social behavior, feeding and reward.

Load-aware modeling for uplink cellular networks in a multi-channel environment

KAUST Repository

Alammouri, Ahmad; Elsawy, Hesham; Alouini, Mohamed-Slim

2014-01-01

We exploit tools from stochastic geometry to develop a tractable analytical approach for modeling uplink cellular networks. The developed model is load aware and accounts for per-user power control as well as the limited transmit power constraint

Parameters and characteristics governing cellular internalization and trans-barrier trafficking of nanostructures

Directory of Open Access Journals (Sweden)

Murugan K

2015-03-01

Full Text Available Karmani Murugan, Yahya E Choonara, Pradeep Kumar, Divya Bijukumar, Lisa C du Toit, Viness Pillay Wits Advanced Drug Delivery Platform Research Unit, Department of Pharmacy and Pharmacology, School of Therapeutic Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa Abstract: Cellular internalization and trans-barrier transport of nanoparticles can be manipulated on the basis of the physicochemical and mechanical characteristics of nanoparticles. Research has shown that these factors significantly influence the uptake of nanoparticles. Dictating these characteristics allows for the control of the rate and extent of cellular uptake, as well as delivering the drug-loaded nanosystem intra-cellularly, which is imperative for drugs that require a specific cellular level to exert their effects. Additionally, physicochemical characteristics of the nanoparticles should be optimal for the nanosystem to bypass the natural restricting phenomena of the body and act therapeutically at the targeted site. The factors at the focal point of emerging smart nanomedicines include nanoparticle size, surface charge, shape, hydrophobicity, surface chemistry, and even protein and ligand conjugates. Hence, this review discusses the mechanism of internalization of nanoparticles and ideal nanoparticle characteristics that allow them to evade the biological barriers in order to achieve optimal cellular uptake in different organ systems. Identifying these parameters assists with the progression of nanomedicine as an outstanding vector of pharmaceuticals. Keywords: nanoparticles, transport mechanisms, cellular uptake, size, shape, charge

Epigenetics and Cellular Metabolism

Directory of Open Access Journals (Sweden)

Wenyi Xu

2016-01-01

Full Text Available Living eukaryotic systems evolve delicate cellular mechanisms for responding to various environmental signals. Among them, epigenetic machinery (DNA methylation, histone modifications, microRNAs, etc. is the hub in transducing external stimuli into transcriptional response. Emerging evidence reveals the concept that epigenetic signatures are essential for the proper maintenance of cellular metabolism. On the other hand, the metabolite, a main environmental input, can also influence the processing of epigenetic memory. Here, we summarize the recent research progress in the epigenetic regulation of cellular metabolism and discuss how the dysfunction of epigenetic machineries influences the development of metabolic disorders such as diabetes and obesity; then, we focus on discussing the notion that manipulating metabolites, the fuel of cell metabolism, can function as a strategy for interfering epigenetic machinery and its related disease progression as well.

Cellular-based preemption system

Science.gov (United States)

Bachelder, Aaron D. (Inventor)

2011-01-01

A cellular-based preemption system that uses existing cellular infrastructure to transmit preemption related data to allow safe passage of emergency vehicles through one or more intersections. A cellular unit in an emergency vehicle is used to generate position reports that are transmitted to the one or more intersections during an emergency response. Based on this position data, the one or more intersections calculate an estimated time of arrival (ETA) of the emergency vehicle, and transmit preemption commands to traffic signals at the intersections based on the calculated ETA. Additional techniques may be used for refining the position reports, ETA calculations, and the like. Such techniques include, without limitation, statistical preemption, map-matching, dead-reckoning, augmented navigation, and/or preemption optimization techniques, all of which are described in further detail in the above-referenced patent applications.

Cellular and subcellular localization of flavin-monooxygenases involved in glucosinolate biosynthesis

DEFF Research Database (Denmark)

Li, Jing; Kristiansen, Kim A.; Hansen, Bjarne Gram

2011-01-01

the side chain modifications take place despite their importance. Hence, the spatial expression pattern of FMO(GS-OX1-5) genes in Arabidopsis was investigated by expressing green fluorescent protein (GFP) and β-glucuronidase (GUS) fusion genes controlled by FMO(GS-OX1-5) promoters. The cellular...

Effects of pyrethroid pesticide cis-bifenthrin on lipogenesis in hepatic cell line.

Science.gov (United States)

Xiang, Dandan; Chu, Tianyi; Li, Meng; Wang, Qiangwei; Zhu, Guonian

2018-06-01

Mounting evidence suggests there is a link between exposure to synthetic pyrethroids (SPs) and the development of obesity. The information presented in this study suggests that cis-bifenthrin (cis-BF) could activate pregnane X receptor (PXR) mediated pathway and lead to the lipid accumulation of human hepatoma (HepG2) cells. Cells were incubated in the control or different concentrations of cis-BF for 24 h. The 1 × 10 -7  M and 1 × 10 -6  M cis-BF exposure were found to induce cellular triglyceride (TG) accumulation significantly. This phenomenon was further supported by Oil Red O Staining assay. The cis-BF exposure caused upregulation of PXR gene and protein. Correspondingly, we also observed the increased expression of downstream genes involved in lipid formation and the inhibition of the expression of β-oxidation. As chiral pesticide，cis-BF was further conformed to behave enantioselectivity in the lipid metabolism. Rather than 1R-cis-BF, HepG2 cells incubated with 1S-cis-BF exhibited a significant TG accumulation. 1S-cis-BF also showed a higher binding level, of which the KD value was 9.184 × 10 -8  M in the SPR assay, compared with 1R-cis-BF (3.463 × 10 -6  M). In addition, the molecular docking simulation analyses correlated well with the KD values measured by the SPR, indicating that 1S-cis-BF showed a better binding affinity with PXR. The results in this study also elucidates the differences between the two enantiomers of pyrethroid-induced toxicity in lipid metabolism of non-target organism. Copyright © 2018 Elsevier Ltd. All rights reserved.

Probabilistic cellular automata.

Science.gov (United States)

Agapie, Alexandru; Andreica, Anca; Giuclea, Marius

2014-09-01

Cellular automata are binary lattices used for modeling complex dynamical systems. The automaton evolves iteratively from one configuration to another, using some local transition rule based on the number of ones in the neighborhood of each cell. With respect to the number of cells allowed to change per iteration, we speak of either synchronous or asynchronous automata. If randomness is involved to some degree in the transition rule, we speak of probabilistic automata, otherwise they are called deterministic. With either type of cellular automaton we are dealing with, the main theoretical challenge stays the same: starting from an arbitrary initial configuration, predict (with highest accuracy) the end configuration. If the automaton is deterministic, the outcome simplifies to one of two configurations, all zeros or all ones. If the automaton is probabilistic, the whole process is modeled by a finite homogeneous Markov chain, and the outcome is the corresponding stationary distribution. Based on our previous results for the asynchronous case-connecting the probability of a configuration in the stationary distribution to its number of zero-one borders-the article offers both numerical and theoretical insight into the long-term behavior of synchronous cellular automata.

Synthetic Biology: Tools to Design, Build, and Optimize Cellular Processes

Science.gov (United States)

Young, Eric; Alper, Hal

2010-01-01

The general central dogma frames the emergent properties of life, which make biology both necessary and difficult to engineer. In a process engineering paradigm, each biological process stream and process unit is heavily influenced by regulatory interactions and interactions with the surrounding environment. Synthetic biology is developing the tools and methods that will increase control over these interactions, eventually resulting in an integrative synthetic biology that will allow ground-up cellular optimization. In this review, we attempt to contextualize the areas of synthetic biology into three tiers: (1) the process units and associated streams of the central dogma, (2) the intrinsic regulatory mechanisms, and (3) the extrinsic physical and chemical environment. Efforts at each of these three tiers attempt to control cellular systems and take advantage of emerging tools and approaches. Ultimately, it will be possible to integrate these approaches and realize the vision of integrative synthetic biology when cells are completely rewired for biotechnological goals. This review will highlight progress towards this goal as well as areas requiring further research. PMID:20150964

Synthetic Biology: Tools to Design, Build, and Optimize Cellular Processes

Directory of Open Access Journals (Sweden)

Eric Young

2010-01-01

Full Text Available The general central dogma frames the emergent properties of life, which make biology both necessary and difficult to engineer. In a process engineering paradigm, each biological process stream and process unit is heavily influenced by regulatory interactions and interactions with the surrounding environment. Synthetic biology is developing the tools and methods that will increase control over these interactions, eventually resulting in an integrative synthetic biology that will allow ground-up cellular optimization. In this review, we attempt to contextualize the areas of synthetic biology into three tiers: (1 the process units and associated streams of the central dogma, (2 the intrinsic regulatory mechanisms, and (3 the extrinsic physical and chemical environment. Efforts at each of these three tiers attempt to control cellular systems and take advantage of emerging tools and approaches. Ultimately, it will be possible to integrate these approaches and realize the vision of integrative synthetic biology when cells are completely rewired for biotechnological goals. This review will highlight progress towards this goal as well as areas requiring further research.

Synthetic biology: tools to design, build, and optimize cellular processes.

Science.gov (United States)

Young, Eric; Alper, Hal

2010-01-01

The general central dogma frames the emergent properties of life, which make biology both necessary and difficult to engineer. In a process engineering paradigm, each biological process stream and process unit is heavily influenced by regulatory interactions and interactions with the surrounding environment. Synthetic biology is developing the tools and methods that will increase control over these interactions, eventually resulting in an integrative synthetic biology that will allow ground-up cellular optimization. In this review, we attempt to contextualize the areas of synthetic biology into three tiers: (1) the process units and associated streams of the central dogma, (2) the intrinsic regulatory mechanisms, and (3) the extrinsic physical and chemical environment. Efforts at each of these three tiers attempt to control cellular systems and take advantage of emerging tools and approaches. Ultimately, it will be possible to integrate these approaches and realize the vision of integrative synthetic biology when cells are completely rewired for biotechnological goals. This review will highlight progress towards this goal as well as areas requiring further research.

47 CFR 32.5003 - Cellular mobile revenue.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular mobile revenue. 32.5003 Section 32... SYSTEM OF ACCOUNTS FOR TELECOMMUNICATIONS COMPANIES Instructions For Revenue Accounts § 32.5003 Cellular mobile revenue. This account shall include message revenue derived from cellular mobile...

Imaging the lipidome: omega-alkynyl fatty acids for detection and cellular visualization of lipid-modified proteins.

Science.gov (United States)

Hannoush, Rami N; Arenas-Ramirez, Natalia

2009-07-17

Fatty acylation or lipid modification of proteins controls their cellular activation and diverse roles in physiology. It mediates protein-protein and protein-membrane interactions and plays an important role in regulating cellular signaling pathways. Currently, there is need for visualizing lipid modifications of proteins in cells. Herein we report novel chemical probes based on omega-alkynyl fatty acids for biochemical detection and cellular imaging of lipid-modified proteins. Our study shows that omega-alkynyl fatty acids of varying chain length are metabolically incorporated onto cellular proteins. Using fluorescence imaging, we describe the subcellular distribution of lipid-modified proteins across a panel of different mammalian cell lines and during cell division. Our results demonstrate that this methodology is a useful diagnostic tool for analyzing the lipid content of cellular proteins and for studying the dynamic behavior of lipid-modified proteins in various disease or physiological states.

The Digital Age of Mobile Cellular Network in Germany and China :Policies, Technologies and Markets (PartⅠ)

Institute of Scientific and Technical Information of China (English)

Mingtao Shi

2009-01-01

The German Postal Reform Ⅰ in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built DI-, D2-, El- and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicorn competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmarm conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars bad led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular Services, the two national markets in the 1990s were visibly shaped by product homogeneity.

The influence of sex and gonadectomy on hepatic and brain fatty acid composition, lipogenesis and β-oxidation.

Science.gov (United States)

Starčević, K; Filipović, N; Šperanda, M; Đidara, M; Mašek, T

2017-08-01

The aim of this study was to investigate the influence of sex and castration of rats on liver and brain fatty acid profile and liver mRNA expression of genes involved in lipogenesis and β-oxidation. Castration significantly increased body weight and liver index and decreased serum triglyceride content in the female rats. The fatty acid composition of the liver tissue was influenced by sex and castration. Male rats had higher content of C16:0, C18:1n7, C18:2n6 and C22:5n3, while female rats had higher content of C18:0, C20:4n6 and C22:6n3. Castration of male rats decreased differences caused by sex for C18:2n6, C20:4n6 and C22:6n3. Values for C16:1n7 were higher in the castrated male rats in comparison with all other groups. Liver phospholipids showed a distribution of fatty acids similar to the total lipids. Brain total lipids and phospholipids were not influenced by sex or castration. Castration increased ∆6D gene expression in both the sexes, while ∆5D and ∆9D increased in females and males respectively. Gonadectomy increased expression of the FASN gene in the females and decreased CPT1 and ACOX1 gene expression in the liver tissue of male rats. The observed results of lipid peroxidation, measured by TBARS, were the lowest in the intact females in comparison with all other groups. In conclusion, sex strongly influences both SFA and PUFA in liver tissue, and castration decreases these differences only for PUFA. Castration also influences the expression of the genes involved in lipid metabolism differently in male and female rats, with an increase in lipogenic genes in female rats and a decrease in key genes for mitochondrial and peroxisomal β-oxidation in male rats. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Cellular and biochemical responses of the oyster Crassostrea gigas to controlled exposures to metals and Alexandrium minutum

Energy Technology Data Exchange (ETDEWEB)

Haberkorn, Hansy; Lambert, Christophe; Le Goïc, Nelly [Laboratoire des Sciences de l‘Environnement Marin, UMR 6539, Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, Place Copernic, Technopôle Brest-Iroise, 29280 Plouzané (France); Quéré, Claudie [IFREMER Centre de Brest, Laboratoire de Physiologie des Invertébrés, Unité Physiologie Fonctionnelle des Organismes Marins, BP 70, 29280 Plouzané (France); Bruneau, Audrey; Riso, Ricardo; Auffret, Michel [Laboratoire des Sciences de l‘Environnement Marin, UMR 6539, Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, Place Copernic, Technopôle Brest-Iroise, 29280 Plouzané (France); Soudant, Philippe, E-mail: Philippe.Soudant@univ-brest.fr [Laboratoire des Sciences de l‘Environnement Marin, UMR 6539, Institut Universitaire Européen de la Mer, Université de Bretagne Occidentale, Place Copernic, Technopôle Brest-Iroise, 29280 Plouzané (France)

2014-02-15

Highlights: •Oysters, C. gigas, were exposed to both metals and PST-producer A. minutum. •Oysters exposed to metals accumulated about thirty-six times less PSTs. •Exposure to both metals and A. minutum induced antagonistic or synergetic effects. -- Abstract: Effects of simultaneous exposure of Pacific oyster, Crassostrea gigas, to both a harmful dinoflagellate that produces Paralytic Shellfish Toxins (PST), Alexandrium minutum, and cadmium (Cd) and copper (Cu), were assessed. Oysters were exposed to a mix of Cd–Cu with two different diets (i.e. A. minutum or Tisochrysis lutea) and compared to control oysters fed A. minutum or T. lutea, respectively, without metal addition. Metals and PST accumulations, digestive gland lipid composition, and cellular and biochemical hemolymph variables were measured after 4 days of exposure. Oysters exposed to Cd–Cu accumulated about thirty-six times less PSTs than oysters exposed to A. minutum alone. Exposure to Cd–Cu induced significant changes in neutral lipids (increase in diacylglycerol – DAG – and decrease in sterols) and phospholipids (decreases in phosphatidylcholine, phosphatidylethanolamine, cardiolipin and ceramide aminoethylphosphonate) of digestive gland suggesting that lipid metabolism disruptions and/or lipid peroxidation have occurred. Simultaneously, concentrations, percentages of dead cells and phenoloxidase activity of hemocytes increased in oysters exposed to metals while reactive oxygen species production of hemocytes decreased. Feeding on the harmful dinoflagellate A. minutum resulted in significant decreases in monoacylglycerol (MAG) and DAG and ether glycerides (EG), as well as significant increases in hemocyte concentration and phagocytic activity as compared to oysters fed T. lutea. Finally, the present study revealed that short-term, simultaneous exposure to Cd–Cu and A. minutum may induce antagonistic (i.e. hemocyte concentration and phagocytosis) or synergic (i.e. DAG content in

Modular design of artificial tissue homeostasis: robust control through synthetic cellular heterogeneity.

Directory of Open Access Journals (Sweden)

Miles Miller

Full Text Available Synthetic biology efforts have largely focused on small engineered gene networks, yet understanding how to integrate multiple synthetic modules and interface them with endogenous pathways remains a challenge. Here we present the design, system integration, and analysis of several large scale synthetic gene circuits for artificial tissue homeostasis. Diabetes therapy represents a possible application for engineered homeostasis, where genetically programmed stem cells maintain a steady population of β-cells despite continuous turnover. We develop a new iterative process that incorporates modular design principles with hierarchical performance optimization targeted for environments with uncertainty and incomplete information. We employ theoretical analysis and computational simulations of multicellular reaction/diffusion models to design and understand system behavior, and find that certain features often associated with robustness (e.g., multicellular synchronization and noise attenuation are actually detrimental for tissue homeostasis. We overcome these problems by engineering a new class of genetic modules for 'synthetic cellular heterogeneity' that function to generate beneficial population diversity. We design two such modules (an asynchronous genetic oscillator and a signaling throttle mechanism, demonstrate their capacity for enhancing robust control, and provide guidance for experimental implementation with various computational techniques. We found that designing modules for synthetic heterogeneity can be complex, and in general requires a framework for non-linear and multifactorial analysis. Consequently, we adapt a 'phenotypic sensitivity analysis' method to determine how functional module behaviors combine to achieve optimal system performance. We ultimately combine this analysis with Bayesian network inference to extract critical, causal relationships between a module's biochemical rate-constants, its high level functional behavior in

Modular design of artificial tissue homeostasis: robust control through synthetic cellular heterogeneity.

Science.gov (United States)

Miller, Miles; Hafner, Marc; Sontag, Eduardo; Davidsohn, Noah; Subramanian, Sairam; Purnick, Priscilla E M; Lauffenburger, Douglas; Weiss, Ron

2012-01-01

Synthetic biology efforts have largely focused on small engineered gene networks, yet understanding how to integrate multiple synthetic modules and interface them with endogenous pathways remains a challenge. Here we present the design, system integration, and analysis of several large scale synthetic gene circuits for artificial tissue homeostasis. Diabetes therapy represents a possible application for engineered homeostasis, where genetically programmed stem cells maintain a steady population of β-cells despite continuous turnover. We develop a new iterative process that incorporates modular design principles with hierarchical performance optimization targeted for environments with uncertainty and incomplete information. We employ theoretical analysis and computational simulations of multicellular reaction/diffusion models to design and understand system behavior, and find that certain features often associated with robustness (e.g., multicellular synchronization and noise attenuation) are actually detrimental for tissue homeostasis. We overcome these problems by engineering a new class of genetic modules for 'synthetic cellular heterogeneity' that function to generate beneficial population diversity. We design two such modules (an asynchronous genetic oscillator and a signaling throttle mechanism), demonstrate their capacity for enhancing robust control, and provide guidance for experimental implementation with various computational techniques. We found that designing modules for synthetic heterogeneity can be complex, and in general requires a framework for non-linear and multifactorial analysis. Consequently, we adapt a 'phenotypic sensitivity analysis' method to determine how functional module behaviors combine to achieve optimal system performance. We ultimately combine this analysis with Bayesian network inference to extract critical, causal relationships between a module's biochemical rate-constants, its high level functional behavior in isolation, and

47 CFR 22.905 - Channels for cellular service.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Channels for cellular service. 22.905 Section... MOBILE SERVICES Cellular Radiotelephone Service § 22.905 Channels for cellular service. The following frequency bands are allocated for assignment to service providers in the Cellular Radiotelephone Service. (a...

Influence of Some Pesticides on Humoral and Cellular Immunity of Exposed Workers in Pesticides Industries

International Nuclear Information System (INIS)

Osely, E.Sh.M.

2010-01-01

Pesticide poisoning is a major public health problem in developing countries. In most of these countries organophosphate pesticides constitute the most widely used pesticides. The main toxicity of OPs is neurotoxicity, which is caused by the inhibition of acetylcholinesterase. OPs also affect the immune response, including effects on cellular and humoral immunity. Our study examined the effect of organophosphorus compounds on humoral and cellular immunity of exposed workers in pesticides industries. The study was conducted into 40 subjects. They were 2 groups; 20 exposed workers from Gharbeia and Kafr Elsheikh at 2008 and 2009 and 20 unexposed individuals as a control group at the same period of time. We examined some immune parameters; pseudocholinesterase, WBCs count, CD4%, CD8%, CD4/CD8, CD56%, Interleukin 2, IgG and IgM. Also we take history and clinical examination for them. We reported a highly significant decrease in pseudo cholinesterase level among the exposed group in comparison to the control group, highly significant increase in percentage of CD8 in the exposed group in comparison to control group, highly significant decrease in CD4 / CD8 ratio in the exposed group in comparison to control group, highly significant decrease in percentage of CD56 in the exposed group in comparison to control group and a highly significant increase in IgG level in the exposed group in comparison to control group. On the other hand, we reported no significant change in white blood cells count between the exposed and control groups, no significant change in percentage of CD4 among the exposed and control group, no significant change in Interleukin 2 level among the exposed and control group and no significant change in IgM level among the exposed and control group. We concluded that pesticides extensively affect the humoral and cellular immune system of occupationally exposed workers.

Hepatitis C virus NS2 protein activates cellular cyclic AMP-dependent pathways

International Nuclear Information System (INIS)

Kim, Kyoung Mi; Kwon, Shi-Nae; Kang, Ju-Il; Lee, Song Hee; Jang, Sung Key; Ahn, Byung-Yoon; Kim, Yoon Ki

2007-01-01

Chronic infection of the hepatitis C virus (HCV) leads to liver cirrhosis and cancer. The mechanism leading to viral persistence and hepatocellular carcinoma, however, has not been fully understood. In this study, we show that the HCV infection activates cellular cAMP-dependent pathways. Expression of a luciferase reporter gene controlled by a basic promoter with the cAMP response element (CRE) was significantly elevated in human hepatoma Huh-7 cells infected with the HCV JFH1. Analysis with viral subgenomic replicons indicated that the HCV NS2 protein is responsible for the effect. Furthermore, the level of cellular transcripts whose stability is known to be regulated by cAMP was specifically reduced in cells harboring NS2-expressing replicons. These results allude to the HCV NS2 protein having a novel function of regulating cellular gene expression and proliferation through the cAMP-dependent pathway

Nanoparticle Surface Functionality Dictates Cellular and Systemic Toxicity

DEFF Research Database (Denmark)

Saei, Amir Ata; Yazdani, Mahdieh; Lohse, Samuel E.

2017-01-01

can greatly enhance subsequent therapeutic effects of NPs while diminishing their adverse side effects. In this review, we will focus on the effect of surface functionality on the cellular uptake and the transport of NPs by various subcellular processes.......Engineered nanoparticles (NPs) have opened new frontiers in therapeutics and diagnostics in recent years. The surface functionality of these nanoparticles often predominates their interactions with various biological components of human body, and proper selection or control of surface functionality...

47 CFR 22.901 - Cellular service requirements and limitations.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Cellular service requirements and limitations... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.901 Cellular service requirements and limitations. The licensee of each cellular system is responsible for ensuring that its cellular system...

Cellular islet autoimmunity associates with clinical outcome of islet cell transplantation.

Directory of Open Access Journals (Sweden)

Volkert A L Huurman

2008-06-01

Full Text Available Islet cell transplantation can cure type 1 diabetes (T1D, but only a minority of recipients remains insulin-independent in the following years. We tested the hypothesis that allograft rejection and recurrent autoimmunity contribute to this progressive loss of islet allograft function.Twenty-one T1D patients received cultured islet cell grafts prepared from multiple donors and transplanted under anti-thymocyte globulin (ATG induction and tacrolimus plus mycophenolate mofetil (MMF maintenance immunosuppression. Immunity against auto- and alloantigens was measured before and during one year after transplantation. Cellular auto- and alloreactivity was assessed by lymphocyte stimulation tests against autoantigens and cytotoxic T lymphocyte precursor assays, respectively. Humoral reactivity was measured by auto- and alloantibodies. Clinical outcome parameters--including time until insulin independence, insulin independence at one year, and C-peptide levels over one year--remained blinded until their correlation with immunological parameters. All patients showed significant improvement of metabolic control and 13 out of 21 became insulin-independent. Multivariate analyses showed that presence of cellular autoimmunity before and after transplantation is associated with delayed insulin-independence (p = 0.001 and p = 0.01, respectively and lower circulating C-peptide levels during the first year after transplantation (p = 0.002 and p = 0.02, respectively. Seven out of eight patients without pre-existent T-cell autoreactivity became insulin-independent, versus none of the four patients reactive to both islet autoantigens GAD and IA-2 before transplantation. Autoantibody levels and cellular alloreactivity had no significant association with outcome.In this cohort study, cellular islet-specific autoimmunity associates with clinical outcome of islet cell transplantation under ATG-tacrolimus-MMF immunosuppression. Tailored immunotherapy targeting cellular

Olanzapine promotes fat accumulation in male rats by decreasing physical activity, repartitioning energy and increasing adipose tissue lipogenesis while impairing lipolysis.

Science.gov (United States)

Albaugh, V L; Judson, J G; She, P; Lang, C H; Maresca, K P; Joyal, J L; Lynch, C J

2011-05-01

Olanzapine and other atypical antipsychotics cause metabolic side effects leading to obesity and diabetes; although these continue to be an important public health concern, their underlying mechanisms remain elusive. Therefore, an animal model of these side effects was developed in male Sprague-Dawley rats. Chronic administration of olanzapine elevated fasting glucose, impaired glucose and insulin tolerance, increased fat mass but, in contrast to female rats, did not increase body weight or food intake. Acute studies were conducted to delineate the mechanisms responsible for these effects. Olanzapine markedly decreased physical activity without a compensatory decline in food intake. It also acutely elevated fasting glucose and worsened oral glucose and insulin tolerance, suggesting that these effects are adiposity independent. Hyperinsulinemic-euglycemic clamp studies measuring (14)C-2-deoxyglucose uptake revealed tissue-specific insulin resistance. Insulin sensitivity was impaired in skeletal muscle, but either unchanged or increased in adipose tissue depots. Consistent with the olanzapine-induced hyperglycemia, there was a tendency for increased (14)C-2-deoxyglucose uptake into fat depots of fed rats and, surprisingly, free fatty acid (FFA) uptake into fat depots was elevated approximately twofold. The increased glucose and FFA uptake into adipose tissue was coupled with increased adipose tissue lipogenesis. Finally, olanzapine lowered fasting plasma FFA, and as it had no effect on isoproterenol-stimulated rises in plasma glucose, it blunted isoproterenol-stimulated in vivo lipolysis in fed rats. Collectively, these results suggest that olanzapine exerts several metabolic effects that together favor increased accumulation of fuel into adipose tissue, thereby increasing adiposity.

Cellular phone use while driving at night.

Science.gov (United States)

Vivoda, Jonathon M; Eby, David W; St Louis, Renée M; Kostyniuk, Lidia P

2008-03-01

Use of a cellular phone has been shown to negatively affect one's attention to the driving task, leading to an increase in crash risk. At any given daylight hour, about 6% of US drivers are actively talking on a hand-held cell phone. However, previous surveys have focused only on cell phone use during the day. Driving at night has been shown to be a riskier activity than driving during the day. The purpose of the current study was to assess the rate of hand-held cellular phone use while driving at night, using specialized night vision equipment. In 2006, two statewide direct observation survey waves of nighttime cellular phone use were conducted in Indiana utilizing specialized night vision equipment. Combined results of driver hand-held cellular phone use from both waves are presented in this manuscript. The rates of nighttime cell phone use were similar to results found in previous daytime studies. The overall rate of nighttime hand-held cellular phone use was 5.8 +/- 0.6%. Cellular phone use was highest for females and for younger drivers. In fact, the highest rate observed during the study (of 11.9%) was for 16-to 29-year-old females. The high level of cellular phone use found within the young age group, coupled with the increased crash risk associated with cellular phone use, nighttime driving, and for young drivers in general, suggests that this issue may become an important transportation-related concern.

Phosphoinositide-3 kinase-Akt pathway controls cellular entry of Ebola virus.

Directory of Open Access Journals (Sweden)

Mohammad F Saeed

2008-08-01

Full Text Available The phosphoinositide-3 kinase (PI3K pathway regulates diverse cellular activities related to cell growth, migration, survival, and vesicular trafficking. It is known that Ebola virus requires endocytosis to establish an infection. However, the cellular signals that mediate this uptake were unknown for Ebola virus as well as many other viruses. Here, the involvement of PI3K in Ebola virus entry was studied. A novel and critical role of the PI3K signaling pathway was demonstrated in cell entry of Zaire Ebola virus (ZEBOV. Inhibitors of PI3K and Akt significantly reduced infection by ZEBOV at an early step during the replication cycle. Furthermore, phosphorylation of Akt-1 was induced shortly after exposure of cells to radiation-inactivated ZEBOV, indicating that the virus actively induces the PI3K pathway and that replication was not required for this induction. Subsequent use of pseudotyped Ebola virus and/or Ebola virus-like particles, in a novel virus entry assay, provided evidence that activity of PI3K/Akt is required at the virus entry step. Class 1A PI3Ks appear to play a predominant role in regulating ZEBOV entry, and Rac1 is a key downstream effector in this regulatory cascade. Confocal imaging of fluorescently labeled ZEBOV indicated that inhibition of PI3K, Akt, or Rac1 disrupted normal uptake of virus particles into cells and resulted in aberrant accumulation of virus into a cytosolic compartment that was non-permissive for membrane fusion. We conclude that PI3K-mediated signaling plays an important role in regulating vesicular trafficking of ZEBOV necessary for cell entry. Disruption of this signaling leads to inappropriate trafficking within the cell and a block in steps leading to membrane fusion. These findings extend our current understanding of Ebola virus entry mechanism and may help in devising useful new strategies for treatment of Ebola virus infection.

Cellular Chaperones As Therapeutic Targets in ALS to Restore Protein Homeostasis and Improve Cellular Function

Directory of Open Access Journals (Sweden)

Bernadett Kalmar

2017-09-01

Full Text Available Heat shock proteins (Hsps are ubiquitously expressed chaperone proteins that enable cells to cope with environmental stresses that cause misfolding and denaturation of proteins. With aging this protein quality control machinery becomes less effective, reducing the ability of cells to cope with damaging environmental stresses and disease-causing mutations. In neurodegenerative disorders such as Amyotrophic Lateral Sclerosis (ALS, such mutations are known to result in protein misfolding, which in turn results in the formation of intracellular aggregates cellular dysfunction and eventual neuronal death. The exact cellular pathology of ALS and other neurodegenerative diseases has been elusive and thus, hindering the development of effective therapies. However, a common scheme has emerged across these “protein misfolding” disorders, in that the mechanism of disease involves one or more aspects of proteostasis; from DNA transcription, RNA translation, to protein folding, transport and degradation via proteosomal and autophagic pathways. Interestingly, members of the Hsp family are involved in each of these steps facilitating normal protein folding, regulating the rate of protein synthesis and degradation. In this short review we summarize the evidence that suggests that ALS is a disease of protein dyshomeostasis in which Hsps may play a key role. Overwhelming evidence now indicates that enabling protein homeostasis to cope with disease-causing mutations might be a successful therapeutic strategy in ALS, as well as other neurodegenerative diseases. Novel small molecule co-inducers of Hsps appear to be able to achieve this aim. Arimoclomol, a hydroxylamine derivative, has shown promising results in cellular and animal models of ALS, as well as other protein misfolding diseases such as Inclusion Body Myositis (IBM. Initial clinical investigations of Arimoclomol have shown promising results. Therefore, it is possible that the long series of

Role of hepatic de novo lipogenesis in the development of fasting-induced fatty liver in the American mink (Neovison vison).

Science.gov (United States)

Rouvinen-Watt, Kirsti; Harris, Lora; Dick, Morag; Pal, Catherine; Lei, Sha; Mustonen, Anne-Mari; Nieminen, Petteri

2012-10-28

American mink (Neovison vison) develop fatty liver quickly in response to food deprivation, which results in preferential mobilisation of n-3 PUFA. The altered n-3:n-6 PUFA ratio in the liver may activate the endocannabinoid system resulting in increased lipid synthesis. The objective of the present study was to investigate the effects of feeding intensity (80 or 120% RDA), dietary fat source (n-3, n-6 or n-9 fatty acids (FA)) and short-term fasting (1-7 d) on hepatic de novo lipogenesis (DNL) and the development of fatty liver in mink. Significantly elevated expression of mRNA encoding for acetyl-CoA carboxylase-1 (ACC-1) and FA synthase (FAS) was observed in the liver of mink fasted for 5-7 d, while upon re-feeding for 28 d after a 7 d food deprivation, DNL returned to pre-fasting levels. The females had a higher expression of ACC-1 and FAS mRNA than the males. In the non-fasted animals, dietary fat source and feeding intensity had significant effects on ACC-1 mRNA. The highest levels were observed in the mink fed the rapeseed oil (n-9) diet at 80% RDA, while the lowest levels were seen when the same diet was fed at 120% RDA. For FAS, the highest gene expression was seen in the fasted mink fed at 80% RDA and the lowest in the non-fasted mink fed at 80%. It is concluded that short-term food deprivation induces hepatic lipidosis in mink and that during this process, hepatic DNL further exacerbates liver fat accumulation.

On the holistic approach in cellular and cancer biology: nonlinearity, complexity, and quasi-determinism of the dynamic cellular network.

Science.gov (United States)

Waliszewski, P; Molski, M; Konarski, J

1998-06-01

A keystone of the molecular reductionist approach to cellular biology is a specific deductive strategy relating genotype to phenotype-two distinct categories. This relationship is based on the assumption that the intermediary cellular network of actively transcribed genes and their regulatory elements is deterministic (i.e., a link between expression of a gene and a phenotypic trait can always be identified, and evolution of the network in time is predetermined). However, experimental data suggest that the relationship between genotype and phenotype is nonbijective (i.e., a gene can contribute to the emergence of more than just one phenotypic trait or a phenotypic trait can be determined by expression of several genes). This implies nonlinearity (i.e., lack of the proportional relationship between input and the outcome), complexity (i.e. emergence of the hierarchical network of multiple cross-interacting elements that is sensitive to initial conditions, possesses multiple equilibria, organizes spontaneously into different morphological patterns, and is controlled in dispersed rather than centralized manner), and quasi-determinism (i.e., coexistence of deterministic and nondeterministic events) of the network. Nonlinearity within the space of the cellular molecular events underlies the existence of a fractal structure within a number of metabolic processes, and patterns of tissue growth, which is measured experimentally as a fractal dimension. Because of its complexity, the same phenotype can be associated with a number of alternative sequences of cellular events. Moreover, the primary cause initiating phenotypic evolution of cells such as malignant transformation can be favored probabilistically, but not identified unequivocally. Thermodynamic fluctuations of energy rather than gene mutations, the material traits of the fluctuations alter both the molecular and informational structure of the network. Then, the interplay between deterministic chaos, complexity, self

Outer-totalistic cellular automata on graphs

International Nuclear Information System (INIS)

Marr, Carsten; Huett, Marc-Thorsten

2009-01-01

We present an intuitive formalism for implementing cellular automata on arbitrary topologies. By that means, we identify a symmetry operation in the class of elementary cellular automata. Moreover, we determine the subset of topologically sensitive elementary cellular automata and find that the overall number of complex patterns decreases under increasing neighborhood size in regular graphs. As exemplary applications, we apply the formalism to complex networks and compare the potential of scale-free graphs and metabolic networks to generate complex dynamics

Radiation, nitric oxide and cellular death

International Nuclear Information System (INIS)

Dubner, D.; Perez, M.R. Del; Michelin, S.C.; Gisone, P.A.

1997-01-01

The mechanisms of radiation induced cellular death constitute an objective of research ever since the first biological effects of radiation were first observed. The explosion of information produced in the last 20 years calls for a careful analysis due to the apparent contradictory data related to the cellular system studied and the range of doses used. This review focuses on the role of the active oxygen species, in particular the nitric oxides, in its relevance as potential mediator of radiation induced cellular death

Predictability in cellular automata.

Science.gov (United States)

Agapie, Alexandru; Andreica, Anca; Chira, Camelia; Giuclea, Marius

2014-01-01

Modelled as finite homogeneous Markov chains, probabilistic cellular automata with local transition probabilities in (0, 1) always posses a stationary distribution. This result alone is not very helpful when it comes to predicting the final configuration; one needs also a formula connecting the probabilities in the stationary distribution to some intrinsic feature of the lattice configuration. Previous results on the asynchronous cellular automata have showed that such feature really exists. It is the number of zero-one borders within the automaton's binary configuration. An exponential formula in the number of zero-one borders has been proved for the 1-D, 2-D and 3-D asynchronous automata with neighborhood three, five and seven, respectively. We perform computer experiments on a synchronous cellular automaton to check whether the empirical distribution obeys also that theoretical formula. The numerical results indicate a perfect fit for neighbourhood three and five, which opens the way for a rigorous proof of the formula in this new, synchronous case.

Conducting polymer scaffolds for electrical control of cellular functions (Conference Presentation)

Science.gov (United States)

Inal, Sahika; Wan, Alwin M.; Williams, Tiffany V.; Giannelis, Emmanuel P.; Fischbach-Teschl, Claudia; Gourdon, Delphine; Owens, Róisín. M.; Malliaras, George G.

2016-09-01

Considering the limited physiological relevance of 2D cell culture experiments, significant effort was devoted to the development of materials that could more accurately recreate the in vivo cellular microenvironment, and support 3D cell cultures in vitro. (1) One such class of materials is conducting polymers, which are promising due to their compliant mechanical properties, compatibility with biological systems, mixed electrical and ionic conductivity, and ability to form porous structures. (2) In this work, we report the fabrication of a single component, macroporous scaffold made from poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) via an ice-templating method. (3) PEDOT:PSS scaffolds offer tunable pore size, morphology and shape through facile changes in preparation conditions, and are capable of supporting 3D cell cultures due to their biocompatibility and tissue-like elasticity. Moreover, these materials are functional: they exhibit excellent electrochemical switching behavior and significantly lower impedance compared to films. Their electrochemical activity enables their use in the active channel of a state of the art diagnostic tool in the field of bioelectronics, i.e., the organic electrochemical transistor (OECT). The inclusion of cells within the porous architecture affects the impedance of the electrically-conducting polymer network and, thus, may be used as a method to quantify cell growth. The adhesion and pro-angiogenic secretions of mouse fibroblasts cultured within the scaffolds can be controlled by switching the electrochemical state of the polymer prior to cell-seeding. In summary, these smart materials hold promise not only as extracellular matrix-mimicking structures for cell culture, but also as high-performance bioelectronic tools for diagnostic and signaling applications. References [1] M. Holzwarth, P. X. Ma, Journal of Materials Chemistry, 21, 10243-10251 (2011). [2] L. H. Jimison, J. Rivnay, R. M. Owens, in Organic

[Fanconi anemia: cellular and molecular features].

Science.gov (United States)

Macé, G; Briot, D; Guervilly, J-H; Rosselli, F

2007-02-01

Fanconi anemia (FA) is a recessive human cancer prone syndrome featuring bone marrow failure, developmental abnormalities and hypersensitivity to DNA crosslinking agents exposure. 11 among 12 FA gene have been isolated. The biochemical functions of the FANC proteins remain poorly understood. Anyhow, to cope with DNA crosslinks a cell needs a functional FANC pathway. Moreover, the FANC proteins appear to be involved in cell protection against oxidative damage and in the control of TNF-alpha activity. In this review, we describe the current understanding of the FANC pathway and we present how it may be integrated in the complex networks of proteins involved in maintaining the cellular homeostasis.

Effects of motexafin gadolinium on tumor oxygenation and cellular oxygen consumption

International Nuclear Information System (INIS)

Donnelly, E.T.; Liu, Y.; Rockwell, S.; Magda, D.

2003-01-01

Full text: Recent work in our laboratory showed that motexafin gadolinium (MGd, Xcytrin), a drug currently in Phase III clinical trials as an adjuvant to radiation therapy, modulates the oxygen tensions in EMT6 tumors. The median pO 2 increased from the control value of 1.5±0.4 mmHg to 7.4 ± 3.8 mmHg six hours after treatment with 40 μmol/kg MGd and the percentage of severely hypoxic readings in the tumors ( 7 plateau phase EMT6 cells in 3 mL Dulbecco's Modified Eagle's Medium supplemented with 10% dialyzed fetal bovine serum, which contains no ascorbic acid. In the absence of ascorbic acid, 100 μM MGd did not alter the cellular oxygen consumption rate for EMT6 cells significantly. Marked inhibition of cellular oxygen consumption was observed when cells were incubated with 100 μM MGd in medium supplemented with equimolar ascorbic acid (a 31.5% decrease in consumption was observed after 6 hours of treatment). The 5% mannitol vehicle solution with equimolar ascorbic acid had no discernible effect on cellular oxygen consumption. Ascorbic acid may facilitate cellular uptake of MGd via the intermediate formation of a MGd-oxalate complex. These studies suggest that changes in cellular oxygen consumption could contribute to the changes in tumor oxygenation seen after administration of MGd. These experiments were supported by Pharmacyclics and training grant T32CA09085 from the NIH (E.T.D.). We thank Dr. Raymond Russell for allowing us to use his oxygen electrode apparatus

Increased cellular proliferation in rat skeletal muscle and tendon in response to exercise

DEFF Research Database (Denmark)

Skovgaard, Dorthe; Bayer, Monika L; Mackey, Abigail

2010-01-01

PURPOSE: The purpose of this study is to investigate exercise-induced cellular proliferation in rat skeletal muscle/tendon with the use of 3'-[F-18]fluoro-3'deoxythymidine (FLT) and to quantitatively study concomitant changes in the proliferation-associated factor, Ki67. PROCEDURES: Wistar rats (...... = 13) performed 3 days of treadmill running. Cellular proliferation was investigated 3 days before and 48 h after the running exercise with the use of FLT and positron emission tomography/computed tomography (PET/CT). Results were compared to a sedentary control group (n = 10). Image......-derived results were supported by a correlation in calf muscle to Ki67 (protein and mRNA level), while this coherence was not found in tendon. CONCLUSION: FLT-PET seems to be a promising tool for imaging of exercise-induced cellular proliferation in musculo-tendinous tissue....

Cellular characterization of compression induced-damage in live biological samples

Science.gov (United States)

Bo, Chiara; Balzer, Jens; Hahnel, Mark; Rankin, Sara M.; Brown, Katherine A.; Proud, William G.

2011-06-01

Understanding the dysfunctions that high-intensity compression waves induce in human tissues is critical to impact on acute-phase treatments and requires the development of experimental models of traumatic damage in biological samples. In this study we have developed an experimental system to directly assess the impact of dynamic loading conditions on cellular function at the molecular level. Here we present a confinement chamber designed to subject live cell cultures in liquid environment to compression waves in the range of tens of MPa using a split Hopkinson pressure bars system. Recording the loading history and collecting the samples post-impact without external contamination allow the definition of parameters such as pressure and duration of the stimulus that can be related to the cellular damage. The compression experiments are conducted on Mesenchymal Stem Cells from BALB/c mice and the damage analysis are compared to two control groups. Changes in Stem cell viability, phenotype and function are assessed flow cytometry and with in vitro bioassays at two different time points. Identifying the cellular and molecular mechanisms underlying the damage caused by dynamic loading in live biological samples could enable the development of new treatments for traumatic injuries.

Definition of a parameter for a typical specific absorption rate under real boundary conditions of cellular phones in a GSM networkd

Science.gov (United States)

Gerhardt, D.

2003-05-01

Using cellular phones the specific absorption rate (SAR) as a physical value must observe established and internationally defined levels to guarantee human protection. To assess human protection it is necessary to guarantee safety under worst-case conditions (especially maximum transmitting power) using cellular phones. To evaluate the exposure to electromagnetic fields under normal terms of use of cellular phones the limitations of the specific absorption rate must be pointed out. In a mobile radio network normal terms of use of cellular phones, i.e. in interconnection with a fixed radio transmitter of a mobile radio network, power control of the cellular phone as well as the antenna diagram regarding a head phantom are also significant for the real exposure. Based on the specific absorption rate, the antenna diagram regarding a head phantom and taking into consideration the power control a new parameter, the typical absorption rate (SARtyp), is defined in this contribution. This parameter indicates the specific absorption rate under average normal conditions of use. Constant radio link attenuation between a cellular phone and a fixed radio transmitter for all mobile models tested was assumed in order to achieve constant field strength at the receiving antenna of the fixed radio transmitter as a result of power control. The typical specific absorption rate is a characteristic physical value of every mobile model. The typical absorption rate was calculated for 16 different mobile models and compared with the absorption rate at maximum transmitting power. The results confirm the relevance of the definition of this parameter (SARtyp) as opposed to the specific absorption rate as a competent and applicable method to establish the real mean exposure from a cellular phone in a mobile radio network. The typical absorption rate provides a parameter to assess electromagnetic fields of a cellular phone that is more relevant to the consumer.

Imaging in cellular and tissue engineering

CERN Document Server

Yu, Hanry

2013-01-01

Details on specific imaging modalities for different cellular and tissue engineering applications are scattered throughout articles and chapters in the literature. Gathering this information into a single reference, Imaging in Cellular and Tissue Engineering presents both the fundamentals and state of the art in imaging methods, approaches, and applications in regenerative medicine. The book underscores the broadening scope of imaging applications in cellular and tissue engineering. It covers a wide range of optical and biological applications, including the repair or replacement of whole tiss

Mobility-Aware User Association in Uplink Cellular Networks

KAUST Repository

Arshad, Rabe; Elsawy, Hesham; Sorour, Sameh; Alouini, Mohamed-Slim; Al-Naffouri, Tareq Y.

2017-01-01

This letter studies the mobility aware user-to-BS association policies, within a stochastic geometry framework, in two tier uplink cellular networks with fractional channel inversion power control. Particularly, we model the base stations’ locations using the widely accepted poisson point process and obtain the coverage probability and handover cost expressions for the coupled and decoupled uplink and downlink associations. To this end, we compute the average throughput for the mobile users and study the merits and demerits of each association strategy.

Mobility-Aware User Association in Uplink Cellular Networks

KAUST Repository

Arshad, Rabe

2017-07-20

This letter studies the mobility aware user-to-BS association policies, within a stochastic geometry framework, in two tier uplink cellular networks with fractional channel inversion power control. Particularly, we model the base stations’ locations using the widely accepted poisson point process and obtain the coverage probability and handover cost expressions for the coupled and decoupled uplink and downlink associations. To this end, we compute the average throughput for the mobile users and study the merits and demerits of each association strategy.

The Digital Age of Mobile Cellular Network in Germany and China: Policies, Technologies and Markets (Part Ⅱ)

Institute of Scientific and Technical Information of China (English)

Mingtao Shi

2009-01-01

The German Postal Reform Ⅰ in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built D1-, D2-, El-and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicom competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmann conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars had led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular services, the two national markets in the 1990s were visibly shaped by product homogeneity.

Polymorphisms in SREBF1 and SREBF2, two antipsychotic-activated transcription factors controlling cellular lipogenesis, are associated with schizophrenia in German and Scandinavian samples

DEFF Research Database (Denmark)

Le Hellard, S; Mühleisen, T W; Djurovic, S

2010-01-01

Several studies have reported structural brain abnormalities, decreased myelination and oligodendrocyte dysfunction in schizophrenia. In the central nervous system, glia-derived de novo synthesized cholesterol is essential for both myelination and synaptogenesis. Previously, we demonstrated...

Polymorphisms in SREBF1 and SREBF2, two antipsychotic-activated transcription factors controlling cellular lipogenesis, are associated with schizophrenia in German and Scandinavian samples

DEFF Research Database (Denmark)

Le Hellard, S; Mühleisen, T W; Djurovic, S

2010-01-01

Several studies have reported structural brain abnormalities, decreased myelination and oligodendrocyte dysfunction in schizophrenia. In the central nervous system, glia-derived de novo synthesized cholesterol is essential for both myelination and synaptogenesis. Previously, we demonstrated......) and sterol regulatory element binding transcription factor 2 (SREBF2) genes. Considering the importance of these factors in the lipid biosynthesis and their possible involvement in antipsychotic drug effects, we hypothesized that genetic variants of SREBF1 and/or SREBF2 could affect schizophrenia...

BRCA1 affects lipid synthesis through its interaction with acetyl-CoA carboxylase.

Science.gov (United States)

Moreau, Karen; Dizin, Eva; Ray, Hind; Luquain, Céline; Lefai, Etienne; Foufelle, Fabienne; Billaud, Marc; Lenoir, Gilbert M; Venezia, Nicole Dalla

2006-02-10

Germ line alterations in BRCA1 (breast cancer susceptibility gene 1) are associated with an increased susceptibility to breast and ovarian cancer. BRCA1 acts as a scaffold protein implicated in multiple cellular functions, such as transcription, DNA repair, and ubiquitination. However, the molecular mechanisms responsible for tumorigenesis are not yet fully understood. We have recently demonstrated that BRCA1 interacts in vivo with acetyl coenzyme A carboxylase alpha (ACCA) through its tandem of BRCA1 C terminus (BRCT) domains. To understand the biological function of the BRCA1.ACCA complex, we sought to determine whether BRCA1 is a regulator of lipogenesis through its interaction with ACCA. We showed here that RNA inhibition-mediated down-regulation of BRCA1 expression induced a marked increase in the fatty acid synthesis. We then delineated the biochemical characteristics of the complex and found that BRCA1 interacts solely with the phosphorylated and inactive form of ACCA (P-ACCA). Finally, we demonstrated that BRCA1 affects lipid synthesis by preventing P-ACCA dephosphorylation. These results suggest that BRCA1 affects lipogenesis through binding to P-ACCA, providing a new mechanism by which BRCA1 may exert a tumor suppressor function.

Characterizing heterogeneous cellular responses to perturbations.

Science.gov (United States)

Slack, Michael D; Martinez, Elisabeth D; Wu, Lani F; Altschuler, Steven J

2008-12-09

Cellular populations have been widely observed to respond heterogeneously to perturbation. However, interpreting the observed heterogeneity is an extremely challenging problem because of the complexity of possible cellular phenotypes, the large dimension of potential perturbations, and the lack of methods for separating meaningful biological information from noise. Here, we develop an image-based approach to characterize cellular phenotypes based on patterns of signaling marker colocalization. Heterogeneous cellular populations are characterized as mixtures of phenotypically distinct subpopulations, and responses to perturbations are summarized succinctly as probabilistic redistributions of these mixtures. We apply our method to characterize the heterogeneous responses of cancer cells to a panel of drugs. We find that cells treated with drugs of (dis-)similar mechanism exhibit (dis-)similar patterns of heterogeneity. Despite the observed phenotypic diversity of cells observed within our data, low-complexity models of heterogeneity were sufficient to distinguish most classes of drug mechanism. Our approach offers a computational framework for assessing the complexity of cellular heterogeneity, investigating the degree to which perturbations induce redistributions of a limited, but nontrivial, repertoire of underlying states and revealing functional significance contained within distinct patterns of heterogeneous responses.

Diet-induced obesity associated with steatosis, oxidative stress, and inflammation in liver.

Science.gov (United States)

Peng, Yanhua; Rideout, Drew; Rakita, Steven; Lee, James; Murr, Michel

2012-01-01

Obesity induces steatosis and increases oxidative stress, as well as chronic inflammation in the liver. The balance between lipogenesis and lipolysis is disrupted in obese animals. At a cellular level, the changes in metabolic sensors and energy regulators are poorly understood. We hypothesized that diet-induced steatosis increases oxidative stress, inflammation, and changes the metabolic regulators to promote energy storage in mice. The setting was a university-affiliated basic science research laboratory. Four-week-old C57BL mice were fed a high-fat diet (n = 8) or regular chow (n = 8) for 7 weeks. The liver sections were stained for fat content and immunofluorescence. Liver homogenates were used for protein analysis by immunoblotting and mRNA analysis by reverse transcriptase-polymerase chain reaction. The gels were quantified using densitometry P ≤ .05 was considered significant. The high-fat diet upregulated protein kinase-C atypical isoforms ζ and λ and decreased glucose tolerance and the interaction of insulin receptor substrate 2 with phosphoinositide kinase-3. The high-fat diet increased the transcriptional factors liver X receptor (4321 ± 98 versus 2981 ± 80) and carbohydrate response element-binding protein (5132 ± 135 versus 3076 ± 91), the lipogenesis genes fatty acid binding protein 5, stearoyl-co-enzyme A desaturase-1, and acetyl-co-enzyme A carboxylase protein, and fatty acid synthesis. The high-fat diet decreased 5'-adenosine monophosphate-activated protein kinase (2561 ± 78 versus 1765 ± 65), glucokinase-3β (2.214 ± 34 versus 3356 ± 86), and SIRT1 (2015 ± 76 versus 3567 ± 104) and increased tumor necrosis factor-α (3415 ± 112 versus 2042 ± 65), nuclear factor kappa B (5123 ± 201 versus 2562 ± 103), cyclooxygenase-2 (4230 ± 113 versus 2473 ± 98), nicotinamide-adenine dinucleotide phosphate oxidase (3501 ± 106 versus 1600 ± 69) and reactive oxygen species production (all P high-fat diet impairs glucose tolerance and hepatic

Probing Cellular Dynamics with Mesoscopic Simulations

DEFF Research Database (Denmark)

Shillcock, Julian C.

2010-01-01

Cellular processes span a huge range of length and time scales from the molecular to the near-macroscopic. Understanding how effects on one scale influence, and are themselves influenced by, those on lower and higher scales is a critical issue for the construction of models in Systems Biology....... Advances in computing hardware and software now allow explicit simulation of some aspects of cellular dynamics close to the molecular scale. Vesicle fusion is one example of such a process. Experiments, however, typically probe cellular behavior from the molecular scale up to microns. Standard particle...... soon be coupled to Mass Action models allowing the parameters in such models to be continuously tuned according to the finer resolution simulation. This will help realize the goal of a computational cellular simulation that is able to capture the dynamics of membrane-associated processes...

The sweet path to metabolic demise: fructose and lipid synthesis

Science.gov (United States)

Herman, Mark A.; Samuel, Varman T.

2016-01-01

Epidemiological studies link fructose consumption with metabolic disease, an association attributable in part to fructose mediated lipogenesis. The mechanisms governing fructose-induced lipogenesis and disease remain debated. Acutely, fructose increases de novo lipogenesis through the efficient and uninhibited action of Ketohexokinase and Aldolase B, which yields substrates for fatty-acid synthesis. Chronic fructose consumption further enhances the capacity for hepatic fructose metabolism via activation of several key transcription factors (i.e. SREBP1c and ChREBP), which augment expression of lipogenic enzymes, increasing lipogenesis, further compounding hypertriglyceridemia, and hepatic steatosis. Hepatic insulin resistance develops from diacylglycerol-PKCε mediated impairment of insulin signaling and possibly additional mechanisms. Initiatives that decrease fructose consumption and therapies that block fructose mediated lipogenesis are needed to avert future metabolic pandemics. PMID:27387598

Network-Assisted Distributed Fairness-Aware Interference Coordination for Device-to-Device Communication Underlaid Cellular Networks

Directory of Open Access Journals (Sweden)

Francis Boabang

2017-01-01

Full Text Available Device-to-device (D2D communication underlaid cellular network is considered a key integration feature in future cellular network. However, without properly designed interference management, the interference from D2D transmission tends to degrade the performance of cellular users and D2D pairs. In this work, we proposed a network-assisted distributed interference mitigation scheme to address this issue. Specifically, the base station (BS acts as a control agent that coordinates the cross-tier interference from D2D transmission through a taxation scheme. The cotier interference is controlled by noncooperative game amongst D2D pairs. In general, the outcome of noncooperative game is inefficient due to the selfishness of each player. In our game formulation, reference user who is the victim of cotier interference is factored into the payoff function of each player to obtain fair and efficient outcome. The existence, uniqueness of the Nash Equilibrium (NE, and the convergence of the proposed algorithm are characterized using Variational Inequality theory. Finally, we provide simulation results to evaluate the efficiency of the proposed algorithm.

Growth and cellular ion content of a salt-sensitive symbiotic system Azolla pinnata-Anabaena azollae under NaCl stress.

Science.gov (United States)

Rai, Vandna; Sharma, Naveen Kumar; Rai, Ashwani K

2006-09-01

Salinity, at a concentration of 10 mM NaCl affected the growth of Azolla pinnata-Anabaena azollae association and became lethal at 40 mM. Plants exposed up to 30 mM NaCl exhibited longer roots than the control, especially during the beginning of incubation. Average root number in plants exposed to 10 and 20 mM NaCl remained almost the same as in control. A further rise in NaCl concentration to 30 mM reduced the root number, and roots shed off at 40 mM NaCl. Presence of NaCl in the nutrient solution increased the cellular Na+ of the intact association exhibiting differential accumulation by individual partners, while it reduced the cellular Ca2+ level. However, cellular K+ content did not show significant change. Cellular Na+ based on fresh weight of respective individual partners (host tissues and cyanobiont) remained higher in the host tissues than the cyanobiont, while reverse was true for K+ and Ca2+ contents. The contribution of A. azollae in the total cellular ion content of the association was a little because of meagre contribution of the cyanobiont mass (19-21%). High salt sensitivity of Azolla-Anabaena complex is due to an inability of the association to maintain low Na+ and high Ca2+ cellular level.

Wireless Cellular Mobile Communications

Directory of Open Access Journals (Sweden)

V. Zalud

2002-12-01

Full Text Available In this article is briefly reviewed the history of wireless cellularmobile communications, examined the progress in current secondgeneration (2G cellular standards and discussed their migration to thethird generation (3G. The European 2G cellular standard GSM and itsevolution phases GPRS and EDGE are described somewhat in detail. Thethird generation standard UMTS taking up on GSM/GPRS core network andequipped with a new advanced access network on the basis of codedivision multiple access (CDMA is investigated too. A sketch of theperspective of mobile communication beyond 3G concludes this article.

Modeling and boundary force control of microcantilevers utilized in atomic force microscopy for cellular imaging and characterization

Science.gov (United States)

Eslami, Sohrab

the proposed Euler-Bernoulli model, a more comprehensive model is developed by modeling the probe dynamics and including the effects of the rotary inertia and shear deformation under the same proposed tip-sample interaction force. An extensive comparative study between the Euler-Bernoulli and Timoshenko beam assumptions is conducted for different conditions including different base-excitation amplitudes and higher modes. The results underline that the comprehensive Timoshenko model unveils the effects of the nonlinear interaction force better than the Euler-Bernoulli beam model. In addition to extensive modeling efforts on the microcantilever and its interaction with sample, an adaptive control framework is developed in order to make the microcantilever's tip follow a desired trajectory. This trajectory can further be considered as an important path acquired by the path planning techniques to manipulate the nanoparticles. There is a base excitation considered for this model and can be considered as an input force control to excite the probe by taking advantage of flexibility of the cantilever despite its complexity and under existence of the external nonlinear interaction forces between the tip and sample's surface. When building such complicated controller on top of the proposed comprehensive model, the results could be extended to study a macro-micro hybrid rigid-flexible model of a microrobot to mimic the realistic behavior of the MM3ARTM microrobot. The MM3ARTM microrobot is equipped with a piezoresistive layer which functions as a force sensor and is capable of measuring very slight forces as small as micro to nano-Newton. Two types of controllers are investigated for the case of the tip force control. Lyapunov-based PD and robust adaptive controllers are developed for this purpose and their performances and stabilities are compared. In the experimental part, a platform for performing the automated nanomanipulation and real-time cellular imaging is developed by

Integrated Transceivers for Millimeter Wave and Cellular Communication

OpenAIRE

TIRED, TOBIAS

2016-01-01

Abstract:This doctoral thesis is addresses two topics in integrated circuit design: multiband direct conversion cellular receivers for cellular frequencies and beam steering transmitters for millimeter wave communication for the cellular backhaul. The trend towards cellular terminals supporting ever more different frequency bands has resulted in complex radio frontends with a large number of RF inputs. Common receivers have, for performance reasons, in the past used differential RF inputs. Ho...

Adaptation to a high protein, carbohydrate-free diet induces a marked reduction of fatty acid synthesis and lipogenic enzymes in rat adipose tissue that is rapidly reverted by a balanced diet.

Science.gov (United States)

Brito, S M R C; Moura, M A F; Kawashita, N H; Festuccia, W T L; Garófalo, M A R; Kettelhut, I C; Migliorini, R H

2005-06-01

We have previously shown that in vivo lipogenesis is markedly reduced in liver, carcass, and in 4 different depots of adipose tissue of rats adapted to a high protein, carbohydrate-free (HP) diet. In the present work, we investigate the activity of enzymes involved in lipogenesis in the epididymal adipose tissue (EPI) of rats adapted to an HP diet before and 12 h after a balanced diet was introduced. Rats fed an HP diet for 15 days showed a 60% reduction of EPI fatty acid synthesis in vivo that was accompanied by 45%-55% decreases in the activities of pyruvate dehydrogenase complex, ATP-citrate lyase, acetyl-CoA carboxylase, glucose-6-phosphate dehydrogenase, and malic enzyme. Reversion to a balanced diet for 12 h resulted in a normalization of in vivo EPI lipogenesis, and in a restoration of acetyl-CoA carboxylase activity to levels that did not differ significantly from control values. The activities of ATP-citrate lyase and pyruvate dehydrogenase complex increased to about 75%-86% of control values, but the activities of glucose-6-phosphate dehydrogenase and malic enzyme remained unchanged 12 h after diet reversion. The data indicate that in rats, the adjustment of adipose tissue lipogenic activity is an important component of the metabolic adaptation to different nutritional conditions.

Control of fluxes in metabolic networks

Science.gov (United States)

Basler, Georg; Nikoloski, Zoran; Larhlimi, Abdelhalim; Barabási, Albert-László; Liu, Yang-Yu

2016-01-01

Understanding the control of large-scale metabolic networks is central to biology and medicine. However, existing approaches either require specifying a cellular objective or can only be used for small networks. We introduce new coupling types describing the relations between reaction activities, and develop an efficient computational framework, which does not require any cellular objective for systematic studies of large-scale metabolism. We identify the driver reactions facilitating control of 23 metabolic networks from all kingdoms of life. We find that unicellular organisms require a smaller degree of control than multicellular organisms. Driver reactions are under complex cellular regulation in Escherichia coli, indicating their preeminent role in facilitating cellular control. In human cancer cells, driver reactions play pivotal roles in malignancy and represent potential therapeutic targets. The developed framework helps us gain insights into regulatory principles of diseases and facilitates design of engineering strategies at the interface of gene regulation, signaling, and metabolism. PMID:27197218

Toxicity of pyrolysis gases from some cellular polymers

Science.gov (United States)

Hilado, C. J.; Machado, A. M.

1978-01-01

Various samples of cellular polymers were evaluated for toxicity of pyrolysis gases, using the screening test method developed at the University of San Francisco. The cellular polymer samples included polyimide, polymethacrylimide, polybismaleimide, polyurethane, polyisocyanurate, polyethylene, polychloroprene, polyvinyl chloride, polystyrene, polysiloxane, and polyphosphazene. The cellular polymers exhibited varying levels of toxicity under these test conditions. Among the rigid cellular polymers, times to death were shortest with the imide type foams and longest with polyvinyl chloride and polystyrene. Among the flexible cellular polymers, times to death were shortest with polyimide and polyester, and longest with polychloroprene and polysiloxane. Increased char yield was not necessarily associated with reduced toxicity.

Cellular telephone use and cancer risk

DEFF Research Database (Denmark)

Schüz, Joachim; Jacobsen, Rune; Olsen, Jørgen H.

2006-01-01

BACKGROUND: The widespread use of cellular telephones has heightened concerns about possible adverse health effects. The objective of this study was to investigate cancer risk among Danish cellular telephone users who were followed for up to 21 years. METHODS: This study is an extended follow......-up of a large nationwide cohort of 420,095 persons whose first cellular telephone subscription was between 1982 and 1995 and who were followed through 2002 for cancer incidence. Standardized incidence ratios (SIRs) were calculated by dividing the number of observed cancer cases in the cohort by the number...... expected in the Danish population. RESULTS: A total of 14,249 cancers were observed (SIR = 0.95; 95% confidence interval [CI] = 0.93 to 0.97) for men and women combined. Cellular telephone use was not associated with increased risk for brain tumors (SIR = 0.97), acoustic neuromas (SIR = 0.73), salivary...

Small regulatory RNAs control the multi-cellular adhesive lifestyle of Escherichia coli

DEFF Research Database (Denmark)

Jørgensen, Mikkel Girke; Nielsen, Jesper Sejrup; Boysen, Anders

2012-01-01

Small regulatory RNA molecules have recently been recognized as important regulatory elements of developmental processes in both eukaryotes and bacteria. We here describe a striking example in Escherichia coli that can switch between a single-cell motile lifestyle and a multi-cellular, sessile....... Our demonstration that basal expression of each of the three RNA species is sufficient to downregulate CsgD synthesis and prevent curli formation indicates that all play a prominent role in the curli regulatory network. Our findings provide the first clue as to how the Rcs signalling pathway...... negatively regulates curli synthesis and increase the number of small regulatory RNAs that act directly on the csgD mRNA to five....

Wavefront cellular learning automata.

Science.gov (United States)

Moradabadi, Behnaz; Meybodi, Mohammad Reza

2018-02-01

This paper proposes a new cellular learning automaton, called a wavefront cellular learning automaton (WCLA). The proposed WCLA has a set of learning automata mapped to a connected structure and uses this structure to propagate the state changes of the learning automata over the structure using waves. In the WCLA, after one learning automaton chooses its action, if this chosen action is different from the previous action, it can send a wave to its neighbors and activate them. Each neighbor receiving the wave is activated and must choose a new action. This structure for the WCLA is necessary in many dynamic areas such as social networks, computer networks, grid computing, and web mining. In this paper, we introduce the WCLA framework as an optimization tool with diffusion capability, study its behavior over time using ordinary differential equation solutions, and present its accuracy using expediency analysis. To show the superiority of the proposed WCLA, we compare the proposed method with some other types of cellular learning automata using two benchmark problems.

Wavefront cellular learning automata

Science.gov (United States)

Moradabadi, Behnaz; Meybodi, Mohammad Reza

2018-02-01

This paper proposes a new cellular learning automaton, called a wavefront cellular learning automaton (WCLA). The proposed WCLA has a set of learning automata mapped to a connected structure and uses this structure to propagate the state changes of the learning automata over the structure using waves. In the WCLA, after one learning automaton chooses its action, if this chosen action is different from the previous action, it can send a wave to its neighbors and activate them. Each neighbor receiving the wave is activated and must choose a new action. This structure for the WCLA is necessary in many dynamic areas such as social networks, computer networks, grid computing, and web mining. In this paper, we introduce the WCLA framework as an optimization tool with diffusion capability, study its behavior over time using ordinary differential equation solutions, and present its accuracy using expediency analysis. To show the superiority of the proposed WCLA, we compare the proposed method with some other types of cellular learning automata using two benchmark problems.

Novel Materials for Cellular Nanosensors

DEFF Research Database (Denmark)

Sasso, Luigi

The monitoring of cellular behavior is useful for the advancement of biomedical diagnostics, drug development and the understanding of a cell as the main unit of the human body. Micro- and nanotechnology allow for the creation of functional devices that enhance the study of cellular dynamics...... modifications for electrochemical nanosensors for the detection of analytes released from cells. Two type of materials were investigated, each pertaining to the two different aspects of such devices: peptide nanostructures were studied for the creation of cellular sensing substrates that mimic in vivo surfaces...... and that offer advantages of functionalization, and conducting polymers were used as electrochemical sensor surface modifications for increasing the sensitivity towards relevant analytes, with focus on the detection of dopamine released from cells via exocytosis. Vertical peptide nanowires were synthesized from...

The mTOR inhibitor sirolimus suppresses renal, hepatic, and cardiac tissue cellular respiration.

Science.gov (United States)

Albawardi, Alia; Almarzooqi, Saeeda; Saraswathiamma, Dhanya; Abdul-Kader, Hidaya Mohammed; Souid, Abdul-Kader; Alfazari, Ali S

2015-01-01

The purpose of this in vitro study was to develop a useful biomarker (e.g., cellular respiration, or mitochondrial O2 consumption) for measuring activities of mTOR inhibitors. It measured the effects of commonly used immunosuppressants (sirolimus-rapamycin, tacrolimus, and cyclosporine) on cellular respiration in target tissues (kidney, liver, and heart) from C57BL/6 mice. The mammalian target of rapamycin (mTOR), a serine/ threonine kinase that supports nutrient-dependent cell growth and survival, is known to control energy conversion processes within the mitochondria. Consistently, inhibitors of mTOR (e.g., rapamycin, also known as sirolimus or Rapamune®) have been shown to impair mitochondrial function. Inhibitors of the calcium-dependent serine/threonine phosphatase calcineurin (e.g., tacrolimus and cyclosporine), on the other hand, strictly prevent lymphokine production leading to a reduced T-cell function. Sirolimus (10 μM) inhibited renal (22%, P=0.002), hepatic (39%, Prespiration. Tacrolimus and cyclosporine had no or minimum effects on cellular respiration in these tissues. Thus, these results clearly demonstrate that impaired cellular respiration (bioenergetics) is a sensitive biomarker of the immunosuppressants that target mTOR.

Assessment of radiofrequency exposure from cellular telephone daily use in an epidemiological study: German Validation study of the international case-control study of cancers of the brain--INTERPHONE-Study.

Science.gov (United States)

Berg, Gabriele; Schüz, Joachim; Samkange-Zeeb, Florence; Blettner, Maria

2005-05-01

The objective of the study is to validate self-reported cellular phone use information by comparing it with the cumulative emitted power and duration of calls measured by software-modified cellular phones (SMP). The information was obtained using a questionnaire developed for the international case-control study on the risk of the use of mobile phones in tumours of the brain or salivary gland (INTERPHONE-study). The study was conducted in Bielefeld, Germany. Volunteers were asked to use SMPs instead of their own cellular phones for a period of 1 month. The SMP recorded the power emitted by the mobile phone handset during each base station contact. Information on cellular phone use for the same time period from traffic records of the network providers and from face-to-face interviews with the participants 3 months after the SMP use was assessed. Pearson's correlation coefficients and linear regression models were used to analyse the association between information from the interview and from the SMP. In total, 1757 personal mobile phone calls were recorded for 45 persons by SMP and traffic records. The correlation between the self-reported information about the number and the duration of calls with the cumulative power of calls was 0.50 (P<0.01) and 0.48 (P<0.01), respectively. Almost 23% of the variance of the cumulative power was explained by either the number or the cumulative duration of calls. After inclusion of possible confounding factors in the regression model, the variance increased to 26%. Minor confounding factors were "network provider", "contract form", and "cellular phone model". The number of calls alone is a sufficient parameter to estimate the cumulative power emitted by the handset of a cellular telephone. The cumulative power emitted by these phones is only associated with number of calls but not with possible confounding factors. Using the mobile phone while driving, mainly in cities, or mainly in rural areas is not associated with the recorded

Cellularity of certain quantum endomorphism algebras

DEFF Research Database (Denmark)

Andersen, Henning Haahr; Lehrer, G. I.; Zhang, R.

Let $\\tA=\\Z[q^{\\pm \\frac{1}{2}}][([d]!)\\inv]$ and let $\\Delta_{\\tA}(d)$ be an integral form of the Weyl module of highest weight $d \\in \\N$ of the quantised enveloping algebra $\\U_{\\tA}$ of $\\fsl_2$. We exhibit for all positive integers $r$ an explicit cellular structure for $\\End...... of endomorphism algebras, and another which relates the multiplicities of indecomposable summands to the dimensions of simple modules for an endomorphism algebra. Our cellularity result then allows us to prove that knowledge of the dimensions of the simple modules of the specialised cellular algebra above...

Influence of extra-cellular and intra-cellular acting thiol oxidants on the 45calcium uptake by the islets of Langerhans of the rat

International Nuclear Information System (INIS)

Haegele, R.G.

1981-01-01

The glucose-stimulated calcium uptake by the islets of Langerhans is dependent on the intra-cellular GSH/GSSG ratios. The inhibition of calcium uptake is not the consequence of a direct oxidation of membrane-fixed thiol groups. In contrast, direct oxidation of extra cellular thiols leads to an increase in calcium uptake when intra-cellular oxidation is simultaneously prevented. Since this effect only occurs at high intra-cellular GSH/GSSG ratios it can be assumed that the redox state of extra-cellular thiols is dependent on the redox state of the intra-cellular GSH/GSSG ratios. These findings support the theory that the oxidation of extra-cellular thiols by thiol oxidants leads to an increase in calcium uptake and that the extent of uptake is higher, the more the redox state of the extra-cellular thiols tends towards the reduced state prior to oxidation. (orig./MG) [de

Keynote address: cellular reduction of nitroimidazole drugs: potential for selective chemotherapy and diagnosis of hypoxic cells

International Nuclear Information System (INIS)

Chapman, J.D.; Lee, J.; Meeker, B.E.

1989-01-01

Nitroimidazole drugs were initially developed as selective radiosensitizers of hypoxic cells and, consequently, as adjuvants to improve the local control probabilities of current radiotherapies. Misonidazole (MISO), the prototype radiosensitizing drug, was found in Phase I clinical studies to cause dose-limiting neurotoxicities (mainly peripheral neuropathies). MISO was also found to be cytotoxic in the absence of radiation and to covalently bind to cellular molecules, both processes demonstrating rates much higher in hypoxic compared with oxygenated cells. It is likely that neurotoxicity, cellular cytotoxicity and adduct formation results from reactions between reduction intermediates of MISO and cellular target molecules. Spin-offs from radiosensitizer research include the synthesis and characterization of more potent hypoxic cytotoxins and the exploitation of sensitizer-adducts as probes for measuring cellular and tissue oxygen levels. Current developments in hypoxic cell cytotoxin and hypoxic cell marker research are reviewed with specific examples from studies which characterize the cellular reduction of TF-MISO, (1-(2-nitro-1-imidazolyl)-3[2,2,2-trifluoroethoxy]-2-propanol). 45 references

Modems for emerging digital cellular-mobile radio system

Science.gov (United States)

Feher, Kamilo

1991-01-01

Digital modem techniques for emerging digital cellular telecommunications-mobile radio system applications are described and analyzed. In particular, theoretical performance, experimental results, principles of operation, and various architectures of pi/4-QPSK (pi/4-shifted coherent or differential QPSK) modems for second-generation US digital cellular radio system applications are presented. The spectral/power efficiency and performance of the pi/4-QPSK modems (American and Japanese digital cellular emerging standards) are studied and briefly compared to GMSK (Gaussian minimum-shift keying) modems (proposed for European DECT and GSM cellular standards). Improved filtering strategies and digital pilot-aided (digital channel sounding) techniques are also considered for pi/4-QPSK and other digital modems. These techniques could significantly improve the performance of digital cellular and other digital land mobile and satellite mobile radio systems. More spectrally efficient modem trends for future cellular/mobile (land mobile) and satellite communication systems applications are also highlighted.

Cellular-automata supercomputers for fluid-dynamics modeling

International Nuclear Information System (INIS)

Margolus, N.; Toffoli, T.; Vichniac, G.

1986-01-01

We report recent developments in the modeling of fluid dynamics, and give experimental results (including dynamical exponents) obtained using cellular automata machines. Because of their locality and uniformity, cellular automata lend themselves to an extremely efficient physical realization; with a suitable architecture, an amount of hardware resources comparable to that of a home computer can achieve (in the simulation of cellular automata) the performance of a conventional supercomputer

Treatment Analysis in a Cancer Stem Cell Context Using a Tumor Growth Model Based on Cellular Automata.

Science.gov (United States)

Monteagudo, Ángel; Santos, José

2015-01-01

Cancer can be viewed as an emergent behavior in terms of complex system theory and artificial life, Cellular Automata (CA) being the tool most used for studying and characterizing the emergent behavior. Different approaches with CA models were used to model cancer growth. The use of the abstract model of acquired cancer hallmarks permits the direct modeling at cellular level, where a cellular automaton defines the mitotic and apoptotic behavior of cells, and allows for an analysis of different dynamics of the cellular system depending on the presence of the different hallmarks. A CA model based on the presence of hallmarks in the cells, which includes a simulation of the behavior of Cancer Stem Cells (CSC) and their implications for the resultant growth behavior of the multicellular system, was employed. This modeling of cancer growth, in the avascular phase, was employed to analyze the effect of cancer treatments in a cancer stem cell context. The model clearly explains why, after treatment against non-stem cancer cells, the regrowth capability of CSCs generates a faster regrowth of tumor behavior, and also shows that a continuous low-intensity treatment does not favor CSC proliferation and differentiation, thereby allowing an unproblematic control of future tumor regrowth. The analysis performed indicates that, contrary to the current attempts at CSC control, trying to make CSC proliferation more difficult is an important point to consider, especially in the immediate period after a standard treatment for controlling non-stem cancer cell proliferation.

Biomolecule delivery to engineer the cellular microenvironment for regenerative medicine.

Science.gov (United States)

Bishop, Corey J; Kim, Jayoung; Green, Jordan J

2014-07-01

To realize the potential of regenerative medicine, controlling the delivery of biomolecules in the cellular microenvironment is important as these factors control cell fate. Controlled delivery for tissue engineering and regenerative medicine often requires bioengineered materials and cells capable of spatiotemporal modulation of biomolecule release and presentation. This review discusses biomolecule delivery from the outside of the cell inwards through the delivery of soluble and insoluble biomolecules as well as from the inside of the cell outwards through gene transfer. Ex vivo and in vivo therapeutic strategies are discussed, as well as combination delivery of biomolecules, scaffolds, and cells. Various applications in regenerative medicine are highlighted including bone tissue engineering and wound healing.

Analysis of Human Mobility Based on Cellular Data

Science.gov (United States)

Arifiansyah, F.; Saptawati, G. A. P.

2017-01-01

Nowadays not only adult but even teenager and children have then own mobile phones. This phenomena indicates that the mobile phone becomes an important part of everyday’s life. Based on these indication, the amount of cellular data also increased rapidly. Cellular data defined as the data that records communication among mobile phone users. Cellular data is easy to obtain because the telecommunications company had made a record of the data for the billing system of the company. Billing data keeps a log of the users cellular data usage each time. We can obtained information from the data about communication between users. Through data visualization process, an interesting pattern can be seen in the raw cellular data, so that users can obtain prior knowledge to perform data analysis. Cellular data processing can be done using data mining to find out human mobility patterns and on the existing data. In this paper, we use frequent pattern mining and finding association rules to observe the relation between attributes in cellular data and then visualize them. We used weka tools for finding the rules in stage of data mining. Generally, the utilization of cellular data can provide supporting information for the decision making process and become a data support to provide solutions and information needed by the decision makers.

Terminal addition in a cellular world.

Science.gov (United States)

Torday, J S; Miller, William B

2018-07-01

Recent advances in our understanding of evolutionary development permit a reframed appraisal of Terminal Addition as a continuous historical process of cellular-environmental complementarity. Within this frame of reference, evolutionary terminal additions can be identified as environmental induction of episodic adjustments to cell-cell signaling patterns that yield the cellular-molecular pathways that lead to differing developmental forms. Phenotypes derive, thereby, through cellular mutualistic/competitive niche constructions in reciprocating responsiveness to environmental stresses and epigenetic impacts. In such terms, Terminal Addition flows according to a logic of cellular needs confronting environmental challenges over space-time. A reconciliation of evolutionary development and Terminal Addition can be achieved through a combined focus on cell-cell signaling, molecular phylogenies and a broader understanding of epigenetic phenomena among eukaryotic organisms. When understood in this manner, Terminal Addition has an important role in evolutionary development, and chronic disease might be considered as a form of 'reverse evolution' of the self-same processes. Copyright © 2017. Published by Elsevier Ltd.

Cellular modeling of fault-tolerant multicomputers

Energy Technology Data Exchange (ETDEWEB)

Morgan, G

1987-01-01

Work described was concerned with a novel method for investigation of fault tolerance in large regular networks of computers. Motivation was to provide a technique useful in rapid evaluation of highly reliable systems that exploit the low cost and ease of volume production of simple microcomputer components. First, a system model and simulator based upon cellular automata are developed. This model is characterized by its simplicity and ease of modification when adapting to new types of network. Second, in order to test and verify the predictive capabilities of the cellular system, a more-detailed simulation is performed based upon an existing computational model, that of the Transputer. An example application is used to exercise various systems designed using the cellular model. Using this simulator, experimental results are obtained both for existing well-understood configurations and for more novel types also developed here. In all cases it was found that the cellular model and simulator successfully predicted the ranking in reliability improvement of the systems studied.

Deep sequencing shows microRNA involvement in bovine mammary gland adaptation to diets supplemented with linseed oil or safflower oil.

Science.gov (United States)

Li, Ran; Beaudoin, Frédéric; Ammah, Adolf A; Bissonnette, Nathalie; Benchaar, Chaouki; Zhao, Xin; Lei, Chuzhao; Ibeagha-Awemu, Eveline M

2015-10-30

Bovine milk fat composition is responsive to dietary manipulation providing an avenue to modify the content of fatty acids and especially some specific unsaturated fatty acid (USFA) isomers of benefit to human health. MicroRNAs (miRNAs) regulate gene expression but their specific roles in bovine mammary gland lipogenesis are unclear. The objective of this study was to determine the expression pattern of miRNAs following mammary gland adaptation to dietary supplementation with 5 % linseed or safflower oil using next generation RNA-sequencing. Twenty-four Canadian Holstein dairy cows (twelve per treatment) in mid lactation were fed a control diet (total mixed ration of corn:grass silages) for 28 days followed by a treatment period (control diet supplemented with 5 % linseed or safflower oil) of 28 days. Milk samples were collected weekly for fat and individual fatty acid determination. RNA from mammary gland biopsies harvested on day-14 (control period) and on days +7 and +28 (treatment period) from six randomly selected cows per treatment was subjected to small RNA sequencing. Milk fat percentage decreased significantly (P safflower oil treatments, respectively. Seven miRNAs including six up-regulated (bta-miR-199c, miR-199a-3p, miR-98, miR-378, miR-148b and miR-21-5p) and one down-regulated (bta-miR-200a) were found to be regulated (P < 0.05) by both treatments, and thus considered core differentially expressed (DE) miRNAs. The gene targets of core DE miRNAs have functions related to gene expression and general cellular metabolism (P < 0.05) and are enriched in four pathways of lipid metabolism (3-phosphoinositide biosynthesis, 3-phosphoinositide degradation, D-myo-inisitol-5-phosphate metabolism and the superpathway of inositol phosphate compounds). Our results suggest that DE miRNAs in this study might be important regulators of bovine mammary lipogenesis and metabolism. The novel miRNAs identified in this study will further enrich the bovine miRNome repertoire

Impact of embryo number and periconceptional undernutrition on factors regulating adipogenesis, lipogenesis, and metabolism in adipose tissue in the sheep fetus.

Science.gov (United States)

Lie, Shervi; Morrison, Janna L; Williams-Wyss, Olivia; Ozanne, Susan E; Zhang, Song; Walker, Simon K; Kleemann, David O; MacLaughlin, Severence M; Roberts, Claire T; McMillen, I Caroline

2013-10-15

Maternal undernutrition around the time of conception is associated with an increased risk of insulin resistance in adulthood. We hypothesized that maternal undernutrition during the periconceptional (PCUN: -60 to 7 days) and/or preimplantation (PIUN: 0-7 days) periods would result in a decrease in UCP1 expression and the abundance of insulin signaling molecules and an increase in the abundance of factors that regulate adipogenesis and lipogenesis in fetal perirenal adipose tissue (PAT) and that these effects would be different in singletons and twins. Maternal PCUN and PIUN resulted in a decrease in UCP1 expression in PAT, and PIUN resulted in higher circulating insulin concentrations, an increased abundance of pPKCζ and PDK4, and a decreased abundance of Akt1, phosphorylated mTOR, and PPARγ in PAT in singleton and twin fetuses. In singletons, there was also a decrease in the abundance of p110β in PAT in the PCUN and PIUN groups and an increase in total AMPKα in PAT in the PIUN group. In twins, however, there was an increase in the abundance of mTOR in the PCUN group and an increase in PDK2 and decrease in total AMPKα in the PIUN group. Thus exposure to periconceptional undernutrition programs changes in the thermogenic capacity and the insulin and fatty acid oxidation signaling pathway in visceral fat, and these effects are different in singletons and twins. These findings are important, as the thermogenic capacity of brown fat and the insulin sensitivity of visceral fat are important determinants of the risk of developing obesity and an insulin resistance phenotype in later life.

A radiation measurement study on cellular phone

International Nuclear Information System (INIS)

Mohd Yusof Mohd Ali; Rozaimah Abd Rahim; Roha Tukimin; Khairol Nizam Mohamed; Mohd Amirul Nizam Mohamad Thari; Ahmad Fadzli Ahmad Sanusi

2007-01-01

This paper will explain the radiation level produced by various selected cellular phone from various models and brands available in the market. The result obtained from this study will also recommend whether a cellular phone is safe for public usage or it might cause any effect on public health. Finally, a database of radiation measurement level produced by selected various cellular phone will also be developed and exhibited in this paper. (Author)

Dynamics and mechanisms of quantum dot nanoparticle cellular uptake

Directory of Open Access Journals (Sweden)

Telford William G

2010-06-01

Full Text Available Abstract Background The rapid growth of the nanotechnology industry and the wide application of various nanomaterials have raised concerns over their impact on the environment and human health. Yet little is known about the mechanism of cellular uptake and cytotoxicity of nanoparticles. An array of nanomaterials has recently been introduced into cancer research promising for remarkable improvements in diagnosis and treatment of the disease. Among them, quantum dots (QDs distinguish themselves in offering many intrinsic photophysical properties that are desirable for targeted imaging and drug delivery. Results We explored the kinetics and mechanism of cellular uptake of QDs with different surface coatings in two human mammary cells. Using fluorescence microscopy and laser scanning cytometry (LSC, we found that both MCF-7 and MCF-10A cells internalized large amount of QD655-COOH, but the percentage of endocytosing cells is slightly higher in MCF-7 cell line than in MCF-10A cell line. Live cell fluorescent imaging showed that QD cellular uptake increases with time over 40 h of incubation. Staining cells with dyes specific to various intracellular organelles indicated that QDs were localized in lysosomes. Transmission electron microscopy (TEM images suggested a potential pathway for QD cellular uptake mechanism involving three major stages: endocytosis, sequestration in early endosomes, and translocation to later endosomes or lysosomes. No cytotoxicity was observed in cells incubated with 0.8 nM of QDs for a period of 72 h. Conclusions The findings presented here provide information on the mechanism of QD endocytosis that could be exploited to reduce non-specific targeting, thereby improving specific targeting of QDs in cancer diagnosis and treatment applications. These findings are also important in understanding the cytotoxicity of nanomaterials and in emphasizing the importance of strict environmental control of nanoparticles.

Mobility-Aware Modeling and Analysis of Dense Cellular Networks With $C$ -Plane/ $U$ -Plane Split Architecture

KAUST Repository

Ibrahim, Hazem

2016-09-19

The unrelenting increase in the population of mobile users and their traffic demands drive cellular network operators to densify their network infrastructure. Network densification shrinks the footprint of base stations (BSs) and reduces the number of users associated with each BS, leading to an improved spatial frequency reuse and spectral efficiency, and thus, higher network capacity. However, the densification gain comes at the expense of higher handover rates and network control overhead. Hence, user’s mobility can diminish or even nullifies the foreseen densification gain. In this context, splitting the control plane ( C -plane) and user plane ( U -plane) is proposed as a potential solution to harvest densification gain with reduced cost in terms of handover rate and network control overhead. In this paper, we use stochastic geometry to develop a tractable mobility-aware model for a two-tier downlink cellular network with ultra-dense small cells and C -plane/ U -plane split architecture. The developed model is then used to quantify the effect of mobility on the foreseen densification gain with and without C -plane/ U -plane split. To this end, we shed light on the handover problem in dense cellular environments, show scenarios where the network fails to support certain mobility profiles, and obtain network design insights.

1,4-Naphthoquinones: From Oxidative Damage to Cellular and Inter-Cellular Signaling

Directory of Open Access Journals (Sweden)

Lars-Oliver Klotz

2014-09-01

Full Text Available Naphthoquinones may cause oxidative stress in exposed cells and, therefore, affect redox signaling. Here, contributions of redox cycling and alkylating properties of quinones (both natural and synthetic, such as plumbagin, juglone, lawsone, menadione, methoxy-naphthoquinones, and others to cellular and inter-cellular signaling processes are discussed: (i naphthoquinone-induced Nrf2-dependent modulation of gene expression and its potentially beneficial outcome; (ii the modulation of receptor tyrosine kinases, such as the epidermal growth factor receptor by naphthoquinones, resulting in altered gap junctional intercellular communication. Generation of reactive oxygen species and modulation of redox signaling are properties of naphthoquinones that render them interesting leads for the development of novel compounds of potential use in various therapeutic settings.

Cellular-automata method for phase unwrapping

International Nuclear Information System (INIS)

Ghiglia, D.C.; Mastin, G.A.; Romero, L.A.

1987-01-01

Research into two-dimensional phase unwrapping has uncovered interesting and troublesome inconsistencies that cause path-dependent results. Cellular automata, which are simple, discrete mathematical systems, offered promise of computation in nondirectional, parallel manner. A cellular automaton was discovered that can unwrap consistent phase data in n dimensions in a path-independent manner and can automatically accommodate noise-induced (pointlike) inconsistencies and arbitrary boundary conditions (region partitioning). For data with regional (nonpointlike) inconsistencies, no phase-unwrapping algorithm will converge, including the cellular-automata approach. However, the automata method permits more simple visualization of the regional inconsistencies. Examples of its behavior on one- and two-dimensional data are presented

Integrated Circuit-Based Biofabrication with Common Biomaterials for Probing Cellular Biomechanics.

Science.gov (United States)

Sung, Chun-Yen; Yang, Chung-Yao; Yeh, J Andrew; Cheng, Chao-Min

2016-02-01

Recent advances in bioengineering have enabled the development of biomedical tools with modifiable surface features (small-scale architecture) to mimic extracellular matrices and aid in the development of well-controlled platforms that allow for the application of mechanical stimulation for studying cellular biomechanics. An overview of recent developments in common biomaterials that can be manufactured using integrated circuit-based biofabrication is presented. Integrated circuit-based biofabrication possesses advantages including mass and diverse production capacities for fabricating in vitro biomedical devices. This review highlights the use of common biomaterials that have been most frequently used to study cellular biomechanics. In addition, the influence of various small-scale characteristics on common biomaterial surfaces for a range of different cell types is discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

A cryptosystem based on elementary cellular automata

Science.gov (United States)

Abdo, A. A.; Lian, Shiguo; Ismail, I. A.; Amin, M.; Diab, H.

2013-01-01

Based on elementary cellular automata, a new image encryption algorithm is proposed in this paper. In this algorithm, a special kind of periodic boundary cellular automata with unity attractors is used. From the viewpoint of security, the number of cellular automata attractor states are changed with respect to the encrypted image, and different key streams are used to encrypt different plain images. The cellular neural network with chaotic properties is used as the generator of a pseudo-random key stream. Theoretical analysis and experimental results have both confirmed that the proposed algorithm possesses high security level and good performances against differential and statistical attacks. The comparison with other existing schemes is given, which shows the superiority of the proposal scheme.

On the Capacity of a Cellular CDMA System Reverse Channel

National Research Council Canada - National Science Library

Klitorakis, Petros

2002-01-01

.... The performance of the system is examined under several values of the standard deviation of lognormal shadowing and the power control error for various numbers of users and values of the Nakagami-m variable by using simulations. Finally, a barrage noise jammer will be introduced and its effect seen in the performance of the cellular communication system for a specific value of E(sub b)/N(sub o).

Nested cellular automata

International Nuclear Information System (INIS)

Quasthoff, U.

1985-07-01

Cellular automata by definition consist of a finite or infinite number of cells, say of unit length, with each cell having the same transition function. These cells are usually considered as the smallest elements and so the space filled with these cells becomes discrete. Nevertheless, large pictures created by such cellular automata look very fractal. So we try to replace each cell by a couple of smaller cells, which have the same transition functions as the large ones. There are automata where this replacement does not destroy the macroscopic structure. In these cases this nesting process can be iterated. The paper contains large classes of automata with the above properties. In the case of one dimensional automata with two states and next neighbour interaction and a nesting function of the same type a complete classification is given. (author)

Environment Aware Cellular Networks

KAUST Repository

Ghazzai, Hakim

2015-02-01

The unprecedented rise of mobile user demand over the years have led to an enormous growth of the energy consumption of wireless networks as well as the greenhouse gas emissions which are estimated currently to be around 70 million tons per year. This significant growth of energy consumption impels network companies to pay huge bills which represent around half of their operating expenditures. Therefore, many service providers, including mobile operators, are looking for new and modern green solutions to help reduce their expenses as well as the level of their CO2 emissions. Base stations are the most power greedy element in cellular networks: they drain around 80% of the total network energy consumption even during low traffic periods. Thus, there is a growing need to develop more energy-efficient techniques to enhance the green performance of future 4G/5G cellular networks. Due to the problem of traffic load fluctuations in cellular networks during different periods of the day and between different areas (shopping or business districts and residential areas), the base station sleeping strategy has been one of the main popular research topics in green communications. In this presentation, we present several practical green techniques that provide significant gains for mobile operators. Indeed, combined with the base station sleeping strategy, these techniques achieve not only a minimization of the fossil fuel consumption but also an enhancement of mobile operator profits. We start with an optimized cell planning method that considers varying spatial and temporal user densities. We then use the optimal transport theory in order to define the cell boundaries such that the network total transmit power is reduced. Afterwards, we exploit the features of the modern electrical grid, the smart grid, as a new tool of power management for cellular networks and we optimize the energy procurement from multiple energy retailers characterized by different prices and pollutant

Theoretical aspects of cellular decision-making and information-processing.

Science.gov (United States)

Kobayashi, Tetsuya J; Kamimura, Atsushi

2012-01-01

Microscopic biological processes have extraordinary complexity and variety at the sub-cellular, intra-cellular, and multi-cellular levels. In dealing with such complex phenomena, conceptual and theoretical frameworks are crucial, which enable us to understand seemingly different intra- and inter-cellular phenomena from unified viewpoints. Decision-making is one such concept that has attracted much attention recently. Since a number of cellular behavior can be regarded as processes to make specific actions in response to external stimuli, decision-making can cover and has been used to explain a broad range of different cellular phenomena [Balázsi et al. (Cell 144(6):910, 2011), Zeng et al. (Cell 141(4):682, 2010)]. Decision-making is also closely related to cellular information-processing because appropriate decisions cannot be made without exploiting the information that the external stimuli contain. Efficiency of information transduction and processing by intra-cellular networks determines the amount of information obtained, which in turn limits the efficiency of subsequent decision-making. Furthermore, information-processing itself can serve as another concept that is crucial for understanding of other biological processes than decision-making. In this work, we review recent theoretical developments on cellular decision-making and information-processing by focusing on the relation between these two concepts.

The cellular approach to band structure calculations

International Nuclear Information System (INIS)

Verwoerd, W.S.

1982-01-01

A short introduction to the cellular approach in band structure calculations is given. The linear cellular approach and its potantial applicability in surface structure calculations is given some consideration in particular

Some Properties of topological pressure on cellular automata

Directory of Open Access Journals (Sweden)

Chih-Hung Chang

2014-09-01

Full Text Available This paper investigates the ergodicity and the power rule of the topological pressure of a cellular automaton. If a cellular automaton is either leftmost or rightmost premutive (due to the terminology given by Hedlund [Math.~Syst.~Theor.~3, 320-375, 1969], then it is ergodic with respect to the uniform Bernoulli measure. More than that, the relation of topological pressure between the original cellular automaton and its power rule is expressed in a closed form. As an application, the topological pressure of a linear cellular automaton can be computed explicitly.

The Emergence of Multi-Cellular Robot Organisms through On-line On-board Evolution

NARCIS (Netherlands)

Weel, B.P.M.; Haasdijk, E.W.; Eiben, A.E.

2012-01-01

We investigate whether a swarm of robots can evolve controllers that cause aggregation into 'multi-cellular' robot organisms without a specific reward to do so. To this end, we create a world where aggregated robots receive more energy than individual ones and enable robots to evolve their

Differential cellular responses by oncogenic levels of c-Myc expression in long-term confluent retinal pigment epithelial cells.

Science.gov (United States)

Wang, Yiping; Cheng, Xiangdong; Samma, Muhammad Kaleem; Kung, Sam K P; Lee, Clement M; Chiu, Sung Kay

2018-06-01

c-Myc is a highly pleiotropic transcription factor known to control cell cycle progression, apoptosis, and cellular transformation. Normally, ectopic expression of c-Myc is associated with promoting cell proliferation or triggering cell death via activating p53. However, it is not clear how the levels of c-Myc lead to different cellular responses. Here, we generated a series of stable RPE cell clones expressing c-Myc at different levels, and found that consistent low level of c-Myc induced cellular senescence by activating AP4 in post-confluent RPE cells, while the cells underwent cell death at high level of c-Myc. In addition, high level of c-Myc could override the effect of AP4 on cellular senescence. Further knockdown of AP4 abrogated senescence-like phenotype in cells expressing low level of c-Myc, and accelerated cell death in cells with medium level of c-Myc, indicating that AP4 was required for cellular senescence induced by low level of c-Myc.

Advanced 3D Printers for Cellular Solids

Science.gov (United States)

2016-06-30

06-2016 1-Aug-2014 31-Dec-2015 Final Report: Advanced 3D printers for Cellular Solids The views, opinions and/or findings contained in this report are...2211 3d printing, cellular solids REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 10. SPONSOR/MONITOR’S ACRONYM(S) ARO 8...Papers published in non peer-reviewed journals: Final Report: Advanced 3D printers for Cellular Solids Report Title Final Report for DURIP grant W911NF

On Elementary and Algebraic Cellular Automata

Science.gov (United States)

Gulak, Yuriy

In this paper we study elementary cellular automata from an algebraic viewpoint. The goal is to relate the emergent complex behavior observed in such systems with the properties of corresponding algebraic structures. We introduce algebraic cellular automata as a natural generalization of elementary ones and discuss their applications as generic models of complex systems.

[Effect of electroacupuncture on cellular structure of hippocampus in splenic asthenia pedo-rats].

Science.gov (United States)

Yang, Zhuo-xin; Zhuo, Yuan-yuan; Yu, Hai-bo; Wang, Ning

2010-02-01

To observe the effect of electroacupuncture (EA) on hippocampal structure in splenic asthenia pedo-rats. A total of 15 SD male rats were randomly assigned to normal control group (n=5), model group (n=5) and EA group (n=5). Splenic asthenic syndrome model was established by intragastric administration of rhubarb and intraperitoneal injection of Reserpine for 14 d. EA (1 mA, 3 Hz/iS Hz) was applied to bilateral "Zusanli" (ST 36) and "Sanyinjiao" (SP 6) for 20 mm, once a day for 14 days. The cellular structure of hippocampus was observed by light microscope and transmission electron microscope. Optical microscopic observation showed that in normal control group, the cellular nucleus was distinct, and the granular cell layer well-arranged and tight. In model group, the intracellular space was widened, and the granular cell layer was out of order in the arrangement. In EA group, the celluldr nucleus and the granular cell layer were nearly normal. Results of the electronic microscope showed that cells in model group had a karyopyknosis with irregular appearance and clear incisure, and some of them presented dissolving and necrotic phenomena; and those in EA group were milder in injury, had nearly-normal nucleus with visible nucleoli and relatively-intact nuclear membrane. Regarding the cellular plasma, in comparison with rich normal organelles of control group, the mitochondria in model group were swelling, with vague, dissolved and broken cristae, while in EA group, majority of the organelles were well-kept, and slightly dissolved mitochondrial cristae found. In regard to the synaptic structure, in comparison with control group, synaptic apomorphosis and swelling mitochondria were found in model group While in EA group, milder swelling and hydropic degeneration were seen. Different from the distinct pre- and post-synaptic membrane and synaptic vesicles of control group, while those in EA group were nearly-normal. electroacupunture can effectively relieve splenasthenic

Comparison of cellular toxicity between multi-walled carbon nanotubes and onion-like shell-shaped carbon nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Kang, Seunghyon [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of); Kim, Ji-Eun [Korea Research Institute of Standard and Science, Center for NanoSafety Metrology, Division of Convergence Technology (Korea, Republic of); Kim, Daegyu [LG Electronics (Korea, Republic of); Woo, Chang Gyu [Korea Institute of Machinery and Materials, Environmental and Energy Systems Research Division (Korea, Republic of); Pikhitsa, Peter V. [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of); Cho, Myung-Haing, E-mail: mchotox@snu.ac.kr [Seoul National University, Laboratory of Toxicology, College of Veterinary Medicine (Korea, Republic of); Choi, Mansoo, E-mail: mchoi@snu.ac.kr [Seoul National University, School of Mechanical and Aerospace Engineering (Korea, Republic of)

2015-09-15

The cellular toxicity of multi-walled carbon nanotubes (MWCNTs) and onion-like shell-shaped carbon nanoparticles (SCNPs) was investigated by analyzing the comparative cell viability. For the reasonable comparison, physicochemical characteristics were controlled thoroughly such as crystallinity, carbon bonding characteristic, hydrodynamic diameter, and metal contents of the particles. To understand relation between cellular toxicity of the particles and generation of reactive oxygen species (ROS), we measured unpaired singlet electrons of the particles and intracellular ROS, and analyzed cellular toxicity with/without the antioxidant N-acetylcysteine (NAC). Regardless of the presence of NAC, the cellular toxicity of SCNPs was found to be lower than that of MWCNTs. Since both particles show similar crystallinity, hydrodynamic size, and Raman signal with negligible contribution of remnant metal particles, the difference in cell viability would be ascribed to the difference in morphology, i.e., spherical shape (aspect ratio of one) for SCNP and elongated shape (high aspect ratio) for MWCNT.

Comparison of cellular toxicity between multi-walled carbon nanotubes and onion-like shell-shaped carbon nanoparticles

International Nuclear Information System (INIS)

Kang, Seunghyon; Kim, Ji-Eun; Kim, Daegyu; Woo, Chang Gyu; Pikhitsa, Peter V.; Cho, Myung-Haing; Choi, Mansoo

2015-01-01

The cellular toxicity of multi-walled carbon nanotubes (MWCNTs) and onion-like shell-shaped carbon nanoparticles (SCNPs) was investigated by analyzing the comparative cell viability. For the reasonable comparison, physicochemical characteristics were controlled thoroughly such as crystallinity, carbon bonding characteristic, hydrodynamic diameter, and metal contents of the particles. To understand relation between cellular toxicity of the particles and generation of reactive oxygen species (ROS), we measured unpaired singlet electrons of the particles and intracellular ROS, and analyzed cellular toxicity with/without the antioxidant N-acetylcysteine (NAC). Regardless of the presence of NAC, the cellular toxicity of SCNPs was found to be lower than that of MWCNTs. Since both particles show similar crystallinity, hydrodynamic size, and Raman signal with negligible contribution of remnant metal particles, the difference in cell viability would be ascribed to the difference in morphology, i.e., spherical shape (aspect ratio of one) for SCNP and elongated shape (high aspect ratio) for MWCNT

Passive Noise Filtering by Cellular Compartmentalization.

Science.gov (United States)

Stoeger, Thomas; Battich, Nico; Pelkmans, Lucas

2016-03-10

Chemical reactions contain an inherent element of randomness, which presents itself as noise that interferes with cellular processes and communication. Here we discuss the ability of the spatial partitioning of molecular systems to filter and, thus, remove noise, while preserving regulated and predictable differences between single living cells. In contrast to active noise filtering by network motifs, cellular compartmentalization is highly effective and easily scales to numerous systems without requiring a substantial usage of cellular energy. We will use passive noise filtering by the eukaryotic cell nucleus as an example of how this increases predictability of transcriptional output, with possible implications for the evolution of complex multicellularity. Copyright © 2016 Elsevier Inc. All rights reserved.

Treatment Analysis in a Cancer Stem Cell Context Using a Tumor Growth Model Based on Cellular Automata.

Directory of Open Access Journals (Sweden)

Ángel Monteagudo

Full Text Available Cancer can be viewed as an emergent behavior in terms of complex system theory and artificial life, Cellular Automata (CA being the tool most used for studying and characterizing the emergent behavior. Different approaches with CA models were used to model cancer growth. The use of the abstract model of acquired cancer hallmarks permits the direct modeling at cellular level, where a cellular automaton defines the mitotic and apoptotic behavior of cells, and allows for an analysis of different dynamics of the cellular system depending on the presence of the different hallmarks. A CA model based on the presence of hallmarks in the cells, which includes a simulation of the behavior of Cancer Stem Cells (CSC and their implications for the resultant growth behavior of the multicellular system, was employed. This modeling of cancer growth, in the avascular phase, was employed to analyze the effect of cancer treatments in a cancer stem cell context. The model clearly explains why, after treatment against non-stem cancer cells, the regrowth capability of CSCs generates a faster regrowth of tumor behavior, and also shows that a continuous low-intensity treatment does not favor CSC proliferation and differentiation, thereby allowing an unproblematic control of future tumor regrowth. The analysis performed indicates that, contrary to the current attempts at CSC control, trying to make CSC proliferation more difficult is an important point to consider, especially in the immediate period after a standard treatment for controlling non-stem cancer cell proliferation.

An agent-based model of cellular dynamics and circadian variability in human endotoxemia.

Directory of Open Access Journals (Sweden)

Tung T Nguyen

Full Text Available As cellular variability and circadian rhythmicity play critical roles in immune and inflammatory responses, we present in this study an agent-based model of human endotoxemia to examine the interplay between circadian controls, cellular variability and stochastic dynamics of inflammatory cytokines. The model is qualitatively validated by its ability to reproduce circadian dynamics of inflammatory mediators and critical inflammatory responses after endotoxin administration in vivo. Novel computational concepts are proposed to characterize the cellular variability and synchronization of inflammatory cytokines in a population of heterogeneous leukocytes. Our results suggest that there is a decrease in cell-to-cell variability of inflammatory cytokines while their synchronization is increased after endotoxin challenge. Model parameters that are responsible for IκB production stimulated by NFκB activation and for the production of anti-inflammatory cytokines have large impacts on system behaviors. Additionally, examining time-dependent systemic responses revealed that the system is least vulnerable to endotoxin in the early morning and most vulnerable around midnight. Although much remains to be explored, proposed computational concepts and the model we have pioneered will provide important insights for future investigations and extensions, especially for single-cell studies to discover how cellular variability contributes to clinical implications.

Bioprinting-Based High-Throughput Fabrication of Three-Dimensional MCF-7 Human Breast Cancer Cellular Spheroids

Directory of Open Access Journals (Sweden)

Kai Ling

2015-06-01

Full Text Available Cellular spheroids serving as three-dimensional (3D in vitro tissue models have attracted increasing interest for pathological study and drug-screening applications. Various methods, including microwells in particular, have been developed for engineering cellular spheroids. However, these methods usually suffer from either destructive molding operations or cell loss and non-uniform cell distribution among the wells due to two-step molding and cell seeding. We have developed a facile method that utilizes cell-embedded hydrogel arrays as templates for concave well fabrication and in situ MCF-7 cellular spheroid formation on a chip. A custom-built bioprinting system was applied for the fabrication of sacrificial gelatin arrays and sequentially concave wells in a high-throughput, flexible, and controlled manner. The ability to achieve in situ cell seeding for cellular spheroid construction was demonstrated with the advantage of uniform cell seeding and the potential for programmed fabrication of tissue models on chips. The developed method holds great potential for applications in tissue engineering, regenerative medicine, and drug screening.

Quantifying the global cellular thiol-disulfide status

DEFF Research Database (Denmark)

Hansen, Rosa E; Roth, Doris; Winther, Jakob R

2009-01-01

It is widely accepted that the redox status of protein thiols is of central importance to protein structure and folding and that glutathione is an important low-molecular-mass redox regulator. However, the total cellular pools of thiols and disulfides and their relative abundance have never been...... determined. In this study, we have assembled a global picture of the cellular thiol-disulfide status in cultured mammalian cells. We have quantified the absolute levels of protein thiols, protein disulfides, and glutathionylated protein (PSSG) in all cellular protein, including membrane proteins. These data...... cell types. However, when cells are exposed to a sublethal dose of the thiol-specific oxidant diamide, PSSG levels increase to >15% of all protein cysteine. Glutathione is typically characterized as the "cellular redox buffer"; nevertheless, our data show that protein thiols represent a larger active...

Nasal lavage cellularity, grain dust, and airflow obstruction.

Science.gov (United States)

Blaski, C A; Watt, J L; Quinn, T J; Thorne, P S; Schwartz, D A

1996-04-01

To evaluate the clinical utility of nasal lavage (NL), we performed post-work shift NL on 172 grain workers and 78 postal worker control subjects. The grain worker group included a higher percentage of current smokers (25.7% vs 16.7%) and a lower percentage of former smokers (21.15% vs 35.9%) compared with the postal workers. The control subjects included more female workers and were slightly older than the grain workers. Compared with the postal workers, the grain workers were exposed to significantly greater concentrations of total dust (0.1 +/- 0.0 vs 6.8 +/- 1.4 mg/m3; mean +/- SEM) and total endotoxin (4.3 +/- 0.8 vs 2,372.4 +/- 653.8 endotoxin units/m3). NL from gain workers showed a higher concentration of total cells (55,000 +/- 14,000 vs 25,000 +/- 5,000 cells per milliliter; p=0.03), a higher concentration of squamous epithelial cells (17,029.0 +/- 4,177 .0 vs 7,103.7 +/- 1,479.8 cells per milliliter; p=0.03), and a higher concentration of neutrophils (40,058.0 +/- 12,803.2 vs 17,891.0 +/- 3,822.3 cells per milliliter; p=0.10) compared with postal workers. Importantly, these differences in NL cellularity between grain workers and postal workers were observed within the three strata of smokers. To further assess the importance of total cells, squamous epithelial cells, and neutrophils in the NL fluid of grain workers, we investigated the relationship between these cell concentrations and (1) measures of dust and endotoxin exposure during the work shift. (2) spirometric measures of airflow obtained immediately before the NL, and (3) work-related respiratory symptoms. The concentration of total cells, the concentration of squamous epithelial cells, or the concentration of neutrophils in the NL was not associated with ambient levels of dust or endotoxin, with baseline or cross-shift changes in lung function, or with work-related respiratory symptoms. These findings suggest that increased NL cellularity may be seen in workers exposed to high dust levels

Wig1 prevents cellular senescence by regulating p21 mRNA decay through control of RISC recruitment.

Science.gov (United States)

Kim, Bong Cho; Lee, Hyung Chul; Lee, Je-Jung; Choi, Chang-Min; Kim, Dong-Kwan; Lee, Jae Cheol; Ko, Young-Gyu; Lee, Jae-Seon

2012-11-14

Premature senescence, a key strategy used to suppress carcinogenesis, can be driven by p53/p21 proteins in response to various stresses. Here, we demonstrate that Wig1 plays a critical role in this process through regulation of p21 mRNA stability. Wig1 controls the association of Argonaute2 (Ago2), a central component of the RNA-induced silencing complex (RISC), with target p21 mRNA via binding of the stem-loop structure near the microRNA (miRNA) target site. Depletion of Wig1 prohibited miRNA-mediated p21 mRNA decay and resulted in premature senescence. Wig1 plays an essential role in cell proliferation, as demonstrated in tumour xenografts in mice, and Wig1 and p21 mRNA levels are inversely correlated in human normal and cancer tissues. Together, our data indicate a novel role of Wig1 in RISC target accessibility, which is a key step in RNA-mediated gene silencing. In addition, these findings indicate that fine-tuning of p21 levels by Wig1 is essential for the prevention of cellular senescence.

HUMORAL AND CELLULAR IMMUNITY PARAMETERS IN CHILDREN BEFORE AND AFTER ADENOTONSILLECTOMY

Directory of Open Access Journals (Sweden)

M. H. Baradaranfar

2007-08-01

Full Text Available Adenoids and tonsils are active lymphoid organs and play an important role ‎against invading antigens of upper aerodigestive tract in children. ‎The present study analyzes the changes in cellular and humoral immunity of children six ‎months after adenotonsillectomy. The study population consisted of 30 children whit chronic adenotonsillar hypertrophy and 30 age-matched healthy children. ‎In all children serum level of IgM and IgG, percentage of T lymphocytes (CD3, T ‎helper cells (CD4, T cytotoxic ‎cells (CD8 and B lymphocytes (CD20 were measured before surgery. These parameters were ‎remeasured in patients 6 months after adenotonsillectomy. ‎Before the operation, a reduction in percentage of T lymphocytes (CD3,TCD4,TC8 ‎and B CD20 was seen compared to control group. This reduction was only significant in T ‎lymphocytes (CD3.The serum IgM and IgG levels were not different in two groups. Six months after ‎operation, the percentage of lymphocytes T CD3, T CD8 and BCD20 was increased and ‎reached the control group. The IgM level was also significantly decreased in patients after ‎operation. ‎Our results indicate that cellular and humoral immunity decreases in children ‎with chronic adenotonsiller hypertrophy preoperatively and increases to healthy children ‎level, six months postoperatively. It means that chronic adenotosillar hypertrophy affect ‎some parameters of cellular and humoral immunity and adenotonsillectomy by removing ‎chronic stimulations and reverses these changes without any negative effect on immune ‎function of patients.

Giardia-specific cellular immune responses in post-giardiasis chronic fatigue syndrome.

Science.gov (United States)

Hanevik, Kurt; Kristoffersen, Einar; Mørch, Kristine; Rye, Kristin Paulsen; Sørnes, Steinar; Svärd, Staffan; Bruserud, Øystein; Langeland, Nina

2017-01-28

The role of pathogen specific cellular immune responses against the eliciting pathogen in development of post-infectious chronic fatigue syndrome (PI-CFS) is not known and such studies are difficult to perform. The aim of this study was to evaluate specific anti-Giardia cellular immunity in cases that developed CFS after Giardia infection compared to cases that recovered well. Patients reporting chronic fatigue in a questionnaire study three years after a Giardia outbreak were clinically evaluated five years after the outbreak and grouped according to Fukuda criteria for CFS and idiopathic chronic fatigue. Giardia specific immune responses were evaluated in 39 of these patients by proliferation assay, T cell activation and cytokine release analysis. 20 Giardia exposed non-fatigued individuals and 10 healthy unexposed individuals were recruited as controls. Patients were clinically classified into CFS (n = 15), idiopathic chronic fatigue (n = 5), fatigue from other causes (n = 9) and recovered from fatigue (n = 10). There were statistically significant antigen specific differences between these Giardia exposed groups and unexposed controls. However, we did not find differences between the Giardia exposed fatigue classification groups with regard to CD4 T cell activation, proliferation or cytokine levels in 6 days cultured PBMCs. Interestingly, sCD40L was increased in patients with PI-CFS and other persons with fatigue after Giardia infection compared to the non-fatigued group, and correlated well with fatigue levels at the time of sampling. Our data show antigen specific cellular immune responses in the groups previously exposed to Giardia and increased sCD40L in fatigued patients.

Characterization and quantification of cellular infiltrates in nasal mucosa of patients with grass pollen allergy, non-allergic patients with nasal polyps and controls

NARCIS (Netherlands)

Fokkens, W. J.; Holm, A. F.; Rijntjes, E.; Mulder, P. G.; Vroom, T. M.

1990-01-01

Little is known about cellular infiltrates in nasal mucosa and the differences between these infiltrates in allergic and non-allergic patients. A reproducible and objective method making use of monoclonal antibodies for the quantification and characterization of cellular infiltrates in biopsy

Cooperative effects of fibronectin matrix assembly and initial cell-substrate adhesion strength in cellular self-assembly.

Science.gov (United States)

Brennan, James R; Hocking, Denise C

2016-03-01

The cell-dependent polymerization of intercellular fibronectin fibrils can stimulate cells to self-assemble into multicellular structures. The local physical cues that support fibronectin-mediated cellular self-assembly are largely unknown. Here, fibronectin matrix analogs were used as synthetic adhesive substrates to model cell-matrix fibronectin fibrils having different integrin-binding specificity, affinity, and/or density. We utilized this model to quantitatively assess the relationship between adhesive forces derived from cell-substrate interactions and the ability of fibronectin fibril assembly to induce cellular self-assembly. Results indicate that the strength of initial, rather than mature, cell-substrate attachments correlates with the ability of substrates to support fibronectin-mediated cellular self-assembly. The cellular response to soluble fibronectin was bimodal and independent of the integrin-binding specificity of the substrate; increasing soluble fibronectin levels above a critical threshold increased aggregate cohesion on permissive substrates. Once aggregates formed, continuous fibronectin polymerization was necessary to maintain cohesion. During self-assembly, soluble fibronectin decreased cell-substrate adhesion strength and induced aggregate cohesion via a Rho-dependent mechanism, suggesting that the balance of contractile forces derived from fibronectin fibrils within cell-cell versus cell-substrate adhesions controls self-assembly and aggregate cohesion. Thus, initial cell-substrate attachment strength may provide a quantitative basis with which to build predictive models of fibronectin-mediated microtissue fabrication on a variety of substrates. Cellular self-assembly is a process by which cells and extracellular matrix (ECM) proteins spontaneously organize into three-dimensional (3D) tissues in the absence of external forces. Cellular self-assembly can be initiated in vitro, and represents a potential tool for tissue engineers to

The Cellular Differential Evolution Based on Chaotic Local Search

Directory of Open Access Journals (Sweden)

Qingfeng Ding

2015-01-01

Full Text Available To avoid immature convergence and tune the selection pressure in the differential evolution (DE algorithm, a new differential evolution algorithm based on cellular automata and chaotic local search (CLS or ccDE is proposed. To balance the exploration and exploitation tradeoff of differential evolution, the interaction among individuals is limited in cellular neighbors instead of controlling parameters in the canonical DE. To improve the optimizing performance of DE, the CLS helps by exploring a large region to avoid immature convergence in the early evolutionary stage and exploiting a small region to refine the final solutions in the later evolutionary stage. What is more, to improve the convergence characteristics and maintain the population diversity, the binomial crossover operator in the canonical DE may be instead by the orthogonal crossover operator without crossover rate. The performance of ccDE is widely evaluated on a set of 14 bound constrained numerical optimization problems compared with the canonical DE and several DE variants. The simulation results show that ccDE has better performances in terms of convergence rate and solution accuracy than other optimizers.

Cellular energy allocation in zebra mussels exposed along a pollution gradient: linking cellular effects to higher levels of biological organization

International Nuclear Information System (INIS)

Smolders, R.; Bervoets, L.; Coen, W. de; Blust, R.

2004-01-01

Organisms exposed to suboptimal environments incur a cost of dealing with stress in terms of metabolic resources. The total amount of energy available for maintenance, growth and reproduction, based on the biochemical analysis of the energy budget, may provide a sensitive measure of stress in an organism. While the concept is clear, linking cellular or biochemical responses to the individual and population or community level remains difficult. The aim of this study was to validate, under field conditions, using cellular energy budgets [i.e. changes in glycogen-, lipid- and protein-content and mitochondrial electron transport system (ETS)] as an ecologically relevant measurement of stress by comparing these responses to physiological and organismal endpoints. Therefore, a 28-day in situ bioassay with zebra mussels (Dreissena polymorpha) was performed in an effluent-dominated stream. Five locations were selected along the pollution gradient and compared with a nearby (reference) site. Cellular Energy Allocation (CEA) served as a biomarker of cellular energetics, while Scope for Growth (SFG) indicated effects on a physiological level and Tissue Condition Index and wet tissue weight/dry tissue weight ratio were used as endpoints of organismal effects. Results indicated that energy budgets at a cellular level of biological organization provided the fastest and most sensitive response and energy budgets are a relevant currency to extrapolate cellular effects to higher levels of biological organization within the exposed mussels. - Exposure of zebra mussels along a pollution gradient has adverse effects on the cellular energy allocation, and results can be linked with higher levels of biological organization

Cellular energy allocation in zebra mussels exposed along a pollution gradient: linking cellular effects to higher levels of biological organization

Energy Technology Data Exchange (ETDEWEB)

Smolders, R.; Bervoets, L.; Coen, W. de; Blust, R

2004-05-01

Organisms exposed to suboptimal environments incur a cost of dealing with stress in terms of metabolic resources. The total amount of energy available for maintenance, growth and reproduction, based on the biochemical analysis of the energy budget, may provide a sensitive measure of stress in an organism. While the concept is clear, linking cellular or biochemical responses to the individual and population or community level remains difficult. The aim of this study was to validate, under field conditions, using cellular energy budgets [i.e. changes in glycogen-, lipid- and protein-content and mitochondrial electron transport system (ETS)] as an ecologically relevant measurement of stress by comparing these responses to physiological and organismal endpoints. Therefore, a 28-day in situ bioassay with zebra mussels (Dreissena polymorpha) was performed in an effluent-dominated stream. Five locations were selected along the pollution gradient and compared with a nearby (reference) site. Cellular Energy Allocation (CEA) served as a biomarker of cellular energetics, while Scope for Growth (SFG) indicated effects on a physiological level and Tissue Condition Index and wet tissue weight/dry tissue weight ratio were used as endpoints of organismal effects. Results indicated that energy budgets at a cellular level of biological organization provided the fastest and most sensitive response and energy budgets are a relevant currency to extrapolate cellular effects to higher levels of biological organization within the exposed mussels. - Exposure of zebra mussels along a pollution gradient has adverse effects on the cellular energy allocation, and results can be linked with higher levels of biological organization.

Acetazolamide Mitigates Astrocyte Cellular Edema Following Mild Traumatic Brain Injury

Science.gov (United States)

Sturdivant, Nasya M.; Smith, Sean G.; Ali, Syed F.; Wolchok, Jeffrey C.; Balachandran, Kartik

2016-09-01

Non-penetrating or mild traumatic brain injury (mTBI) is commonly experienced in accidents, the battlefield and in full-contact sports. Astrocyte cellular edema is one of the major factors that leads to high morbidity post-mTBI. Various studies have reported an upregulation of aquaporin-4 (AQP4), a water channel protein, following brain injury. AZA is an antiepileptic drug that has been shown to inhibit AQP4 expression and in this study we investigate the drug as a therapeutic to mitigate the extent of mTBI induced cellular edema. We hypothesized that mTBI-mediated astrocyte dysfunction, initiated by increased intracellular volume, could be reduced when treated with AZA. We tested our hypothesis in a three-dimensional in vitro astrocyte model of mTBI. Samples were subject to no stretch (control) or one high-speed stretch (mTBI) injury. AQP4 expression was significantly increased 24 hours after mTBI. mTBI resulted in a significant increase in the cell swelling within 30 min of mTBI, which was significantly reduced in the presence of AZA. Cell death and expression of S100B was significantly reduced when AZA was added shortly before mTBI stretch. Overall, our data point to occurrence of astrocyte swelling immediately following mTBI, and AZA as a promising treatment to mitigate downstream cellular mortality.

Transient expression of protein tyrosine phosphatases encoded in Cotesia plutellae bracovirus inhibits insect cellular immune responses

Science.gov (United States)

Ibrahim, Ahmed M. A.; Kim, Yonggyun

2008-01-01

Several immunosuppressive factors are associated with parasitism of an endoparasitoid wasp, Cotesia plutellae, on the diamondback moth, Plutella xylostella. C. plutellae bracovirus (CpBV) encodes a large number of putative protein tyrosine phosphatases (PTPs), which may play a role in inhibiting host cellular immunity. To address this inhibitory hypothesis of CpBV-PTPs, we performed transient expression of individual CpBV-PTPs in hemocytes of the beet armyworm, Spodoptera exigua, and analyzed their cellular immune responses. Two different forms of CpBV-PTPs were chosen and cloned into a eukaryotic expression vector under the control of the p10 promoter of baculovirus: one with the normal cysteine active site (CpBV-PTP1) and the other with a mutated active site (CpBV-PTP5). The hemocytes transfected with CpBV-PTP1 significantly increased in PTP activity compared to control hemocytes, but those with CpBV-PTP5 exhibited a significant decrease in the PTP activity. All transfected hemocytes exhibited a significant reduction in both cell spreading and encapsulation activities compared to control hemocytes. Co-transfection of CpBV-PTP1 together with its double-stranded RNA reduced the messenger RNA (mRNA) level of CpBV-PTP1 and resulted in recovery of both hemocyte behaviors. This is the first report demonstrating that the polydnaviral PTPs can manipulate PTP activity of the hemocytes to interrupt cellular immune responses.

Optimizing Cellular Networks Enabled with Renewal Energy via Strategic Learning.

Science.gov (United States)

Sohn, Insoo; Liu, Huaping; Ansari, Nirwan

2015-01-01

An important issue in the cellular industry is the rising energy cost and carbon footprint due to the rapid expansion of the cellular infrastructure. Greening cellular networks has thus attracted attention. Among the promising green cellular network techniques, the renewable energy-powered cellular network has drawn increasing attention as a critical element towards reducing carbon emissions due to massive energy consumption in the base stations deployed in cellular networks. Game theory is a branch of mathematics that is used to evaluate and optimize systems with multiple players with conflicting objectives and has been successfully used to solve various problems in cellular networks. In this paper, we model the green energy utilization and power consumption optimization problem of a green cellular network as a pilot power selection strategic game and propose a novel distributed algorithm based on a strategic learning method. The simulation results indicate that the proposed algorithm achieves correlated equilibrium of the pilot power selection game, resulting in optimum green energy utilization and power consumption reduction.

Nanoparticle bioconjugate for controlled cellular delivery of doxorubicin

Science.gov (United States)

Sangtani, Ajmeeta; Petryayeva, Eleonora; Wu, Miao; Susumu, Kimihiro; Oh, Eunkeu; Huston, Alan L.; Lasarte-Aragones, Guillermo; Medintz, Igor L.; Algar, W. Russ; Delehanty, James B.

2018-02-01

Nanoparticle (NP)-mediated drug delivery offers the potential to overcome limitations of systemic delivery, including the ability to specifically target cargo and control release of NP-associated drug cargo. Doxorubicin (DOX) is a widely used FDA-approved cancer therapeutic; however, multiple side effects limit its utility. Thus, there is wide interest in modulating toxicity after cell delivery. Our goal here was to realize a NP-based DOX-delivery system that can modulate drug toxicity by controlling the release kinetics of DOX from the surface of a hard NP carrier. To achieve this, we employed a quantum dot (QD) as a central scaffold which DOX was appended via three different peptidyl linkages (ester, disulfide, hydrazone) that are cleavable in response to various intracellular conditions. Attachment of a cell penetrating peptide (CPP) containing a positively charged polyarginine sequence facilitates endocytosis of the ensemble. Polyhistidine-driven metal affinity coordination was used to self-assemble both peptides to the QD surface, allowing for fine control over both the ratio of peptides attached to the QD as well as DOX dose delivered to cells. Microplate-based Förster resonance energy transfer assays confirmed the successful ratiometric assembly of the conjugates and functionality of the linkages. Cell delivery experiments and cytotoxicity assays were performed to compare the various cleavable linkages to a control peptide where DOX is attached through an amide bond. The role played by various attachment chemistries used in QD-peptide-drug assemblies and their implications for the rationale in design of NPbased constructs for drug delivery is described here.

Discussing epigenetics in Southern California: a report from the International Symposium on Epigenetic Control and Cellular Plasticity, UCI, December 15-16, 2011.

Science.gov (United States)

Rattner, Barbara P

2012-04-01

With the goal of discussing how epigenetic control and chromatin remodeling contribute to the various processes that lead to cellular plasticity and disease, this symposium marks the collaboration between the Institut National de la Santé et de la Recherche Médicale (INSERM) in France and the University of California, Irvine (UCI). Organized by Paolo Sassone-Corsi (UCI) and held at the Beckman Center of the National Academy of Sciences at the UCI campus December 15-16, 2011, this was the first of a series of international conferences on epigenetics dedicated to the scientific community in Southern California. The meeting also served as the official kick off for the newly formed Center for Epigenetics and Metabolism at the School of Medicine, UCI (http://cem.igb.uci.edu).

Gravitational Effects on Cellular Flame Structure

Science.gov (United States)

Dunsky, C. M.; Fernandez-Pello, A. C.

1991-01-01

An experimental investigation has been conducted of the effect of gravity on the structure of downwardly propagating, cellular premixed propane-oxygen-nitrogen flames anchored on a water-cooled porous-plug burner. The flame is subjected to microgravity conditions in the NASA Lewis 2.2-second drop tower, and flame characteristics are recorded on high-speed film. These are compared to flames at normal gravity conditions with the same equivalence ratio, dilution index, mixture flow rate, and ambient pressure. The results show that the cellular instability band, which is located in the rich mixture region, changes little under the absence of gravity. Lifted normal-gravity flames near the cellular/lifted limits, however, are observed to become cellular when gravity is reduced. Observations of a transient cell growth period following ignition point to heat loss as being an important mechanism in the overall flame stability, dominating the stabilizing effect of buoyancy for these downwardly-propagating burner-anchored flames. The pulsations that are observed in the plume and diffusion flame generated downstream of the premixed flame in the fuel rich cases disappear in microgravity, verifying that these fluctuations are gravity related.

THE EFFECT OF CELLULAR PHONE USE ON DRIVING PERFORMANCE

OpenAIRE

Toshiro ISHIDA

2001-01-01

Many experiments using driving simulators or real roads have shown that using a cellular phone while driving may cause an accident because it delays visual information processing by the driver. In this research, we examined the influence on driving performance of cellular phone use on a course that simulated streets. Driving conditions were driving only, listening to the car radio, hands-free cellular phone use and using a cellular phone with the left hand. Driving performance measurements in...

Effect of crumb cellular structure characterized by image analysis on cake softness.

Science.gov (United States)

Dewaest, Marine; Villemejane, Cindy; Berland, Sophie; Neron, Stéphane; Clement, Jérôme; Verel, Aliette; Michon, Camille

2017-10-04

Sponge cake is a cereal product characterized by an aerated crumb and appreciated for its softness. When formulating such product, it is interesting to be able to characterize the crumb structure using image analysis and to bring knowledge about the effects of the crumb cellular structure on its mechanical properties which contribute to softness. An image analysis method based on mathematical morphology was adapted from the one developed for bread crumb. In order to evaluate its ability to discriminate cellular structures, series of cakes were prepared using two rather similar emulsifiers but also using flours with different aging times before use. The mechanical properties of the crumbs of these different cakes were also characterized. It allowed a cell structure classification taking into account cell size and homogeneity, but also cell wall thickness and the number of holes in the walls. Interestingly, the cellular structure differences had a larger impact on the aerated crumb Young modulus than the wall firmness. Increasing the aging time of flour before use leads to the production of firmer crumbs due to coarser and inhomogeneous cellular structures. Changing the composition of the emulsifier may change the cellular structure and, depending on the type of the structural changes, have an impact on the firmness of the crumb. Cellular structure rather than cell wall firmness was found to impact cake crumb firmness. The new fast and automated tool for cake crumb structure analysis allows detecting quickly any change in cell size or homogeneity but also cell wall thickness and number of holes in the walls (openness degree). To obtain a softer crumb, it seems that options are to decrease the cell size and the cell wall thickness and/or to increase the openness degree. It is then possible to easily evaluate the effects of ingredients (flour composition, emulsifier …) or change in the process on the crumb structure and thus its softness. Moreover, this image

Global properties of cellular automata

International Nuclear Information System (INIS)

Jen, E.

1986-01-01

Cellular automata are discrete mathematical systems that generate diverse, often complicated, behavior using simple deterministic rules. Analysis of the local structure of these rules makes possible a description of the global properties of the associated automata. A class of cellular automata that generate infinitely many aperoidic temporal sequences is defined,a s is the set of rules for which inverses exist. Necessary and sufficient conditions are derived characterizing the classes of ''nearest-neighbor'' rules for which arbitrary finite initial conditions (i) evolve to a homogeneous state; (ii) generate at least one constant temporal sequence

Induction of cellular transformation by irradiation from artificial light sources

International Nuclear Information System (INIS)

Withrow, T.J.

1981-01-01

Cellular transformation in vitro has been used to test for the carcinogenic potential of chemical and physical insults including light. This report discusses the measurement of transformation, and reviews studies done on the effects of exposure to artificial light on cellular transformation or on cellular transformation by a virus. To date, cool-white lamps have been found to cause cellular transformation, while germicidal lamps and sunlamps have been found to cause cellular transformation and to enhance virally produced transformation

Cellular Neural Networks for NP-Hard Optimization

Directory of Open Access Journals (Sweden)

Mária Ercsey-Ravasz

2009-02-01

Full Text Available A cellular neural/nonlinear network (CNN is used for NP-hard optimization. We prove that a CNN in which the parameters of all cells can be separately controlled is the analog correspondent of a two-dimensional Ising-type (Edwards-Anderson spin-glass system. Using the properties of CNN, we show that one single operation (template always yields a local minimum of the spin-glass energy function. This way, a very fast optimization method, similar to simulated annealing, can be built. Estimating the simulation time needed on CNN-based computers, and comparing it with the time needed on normal digital computers using the simulated annealing algorithm, the results are astonishing. CNN computers could be faster than digital computers already at 10×10 lattice sizes. The local control of the template parameters was already partially realized on some of the hardwares, we think this study could further motivate their development in this direction.

Observations of cellular transformation products in nickel-base superalloys

International Nuclear Information System (INIS)

Barlow, C.Y.; Ralph, B.

1979-01-01

Transmission electron microscopy has been used to identify the products in cellularly transformed regions of alloys based on the Nimonic 80 A composition. The commercial alloy is shown to undergo a small degree of cellular transformation even after conventional heat treatments, while recrystallization is found to increase the incidence of this reaction type. Low carbon versions of this alloy demonstrate cellular precipitation over a wider range of heat treatments. It is shown that the cellular reaction may take place in these alloys under a variety of different conditions and with a range of driving forces. Reasons for this unexpected behaviour are offeredm as is a suggestion as to why the cellular reaction occurs on a local scale. (author)

Cellular Senescence in Postmitotic Cells: Beyond Growth Arrest.

Science.gov (United States)

Sapieha, Przemyslaw; Mallette, Frédérick A

2018-04-25

In mitotic cells, cellular senescence is a permanent state of G1 arrest, that may have evolved in parallel to apoptosis, to limit proliferation of damaged cells and oncogenesis. Recent studies have suggested that postmitotic cells are also capable of entering a state of senescence, although the repercussions of postmitotic cellular senescence (PoMiCS) on tissue health and function are currently ill-defined. In tissues made largely of post-mitotic cells, it is evolutionary advantageous to preserve cellular integrity and cellular senescence of post-mitotic cells may prevent stressor-induced tissue degeneration and promote tissue repair. Paradoxically, PoMiCS may also contribute to disease progression through the generation of inflammatory mediators, termed the senescence-associated secretory phenotype. Here, we discuss the potential roles of PoMiCS and propose to enlarge the current definition of cellular senescence to postmitotic terminally differentiated cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

High-Concentrate Diet-Induced Change of Cellular Metabolism Leads to Decreases of Immunity and Imbalance of Cellular Activities in Rumen Epithelium.

Science.gov (United States)

Lu, Zhongyan; Shen, Hong; Shen, Zanming

2018-01-01

In animals, the immune and cellular processes of tissue largely depend on the status of local metabolism. However, in the rumen epithelium, how the cellular metabolism affects epithelial immunity, and cellular processes, when the diet is switched from energy-rich to energy-excess status, with regard to animal production and health, have not as yet been reported. RNA-seq was applied to compare the biological processes altered by an increase of dietary concentration from 10% to 35% with those altered by an increase of dietary concentration from 35% to 65% (dietary concentrate: the non-grass component in diet, including corn, soya bean meal and additive. High concentrate diet composed of 35% grass, 55% corn, 8% soya bean meal and 2% additive). In addition to the functional analysis of enriched genes in terms of metabolism, the immune system, and cellular process, the highly correlated genes to the enriched metabolism genes were identified, and the function and signaling pathways related to the differentially expressed neighbors were compared among the groups. The variation trends of molar proportions of ruminal SCFAs and those of enriched pathways belonging to metabolism, immune system, and cellular process were altered with the change of diets. With regard to metabolism, lipid metabolism and amino acid metabolism were most affected. According to the correlation analysis, both innate and adaptive immune responses were promoted by the metabolism genes enriched under the 65% concentrate diet. However, the majority of immune responses were suppressed under the 35% concentrate diet. Moreover, the exclusive upregulation of cell growth and dysfunction of cellular transport and catabolism were induced by the metabolism genes enriched under the 65% concentrate diet. On the contrary, a balanced regulation of cellular processes was detected under the 35% concentrate diet. These results indicated that the alterations of cellular metabolism promote the alterations in cellular

High-Concentrate Diet-Induced Change of Cellular Metabolism Leads to Decreases of Immunity and Imbalance of Cellular Activities in Rumen Epithelium

Directory of Open Access Journals (Sweden)

Zhongyan Lu

2018-03-01

Full Text Available Background/Aims: In animals, the immune and cellular processes of tissue largely depend on the status of local metabolism. However, in the rumen epithelium, how the cellular metabolism affects epithelial immunity, and cellular processes, when the diet is switched from energy-rich to energy-excess status, with regard to animal production and health, have not as yet been reported. Methods: RNA-seq was applied to compare the biological processes altered by an increase of dietary concentration from 10% to 35% with those altered by an increase of dietary concentration from 35% to 65% (dietary concentrate: the non-grass component in diet, including corn, soya bean meal and additive. High concentrate diet composed of 35% grass, 55% corn, 8% soya bean meal and 2% additive. In addition to the functional analysis of enriched genes in terms of metabolism, the immune system, and cellular process, the highly correlated genes to the enriched metabolism genes were identified, and the function and signaling pathways related to the differentially expressed neighbors were compared among the groups. Results: The variation trends of molar proportions of ruminal SCFAs and those of enriched pathways belonging to metabolism, immune system, and cellular process were altered with the change of diets. With regard to metabolism, lipid metabolism and amino acid metabolism were most affected. According to the correlation analysis, both innate and adaptive immune responses were promoted by the metabolism genes enriched under the 65% concentrate diet. However, the majority of immune responses were suppressed under the 35% concentrate diet. Moreover, the exclusive upregulation of cell growth and dysfunction of cellular transport and catabolism were induced by the metabolism genes enriched under the 65% concentrate diet. On the contrary, a balanced regulation of cellular processes was detected under the 35% concentrate diet. Conclusions: These results indicated that the

Cellular chain formation in Escherichia coli biofilms

DEFF Research Database (Denmark)

Vejborg, Rebecca Munk; Klemm, Per

2009-01-01

; type I fimbriae expression significantly reduced cellular chain formation, presumably by steric hindrance. Cellular chain formation did not appear to be specific to E coli K-12. Although many urinary tract infection (UTI) isolates were found to form rather homogeneous, flat biofilms, three isolates...

Cellular energy allocation in zebra mussels exposed along a pollution gradient: linking cellular effects to higher levels of biological organization.

Science.gov (United States)

Smolders, R; Bervoets, L; De Coen, W; Blust, R

2004-05-01

Organisms exposed to suboptimal environments incur a cost of dealing with stress in terms of metabolic resources. The total amount of energy available for maintenance, growth and reproduction, based on the biochemical analysis of the energy budget, may provide a sensitive measure of stress in an organism. While the concept is clear, linking cellular or biochemical responses to the individual and population or community level remains difficult. The aim of this study was to validate, under field conditions, using cellular energy budgets [i.e. changes in glycogen-, lipid- and protein-content and mitochondrial electron transport system (ETS)] as an ecologically relevant measurement of stress by comparing these responses to physiological and organismal endpoints. Therefore, a 28-day in situ bioassay with zebra mussels (Dreissena polymorpha) was performed in an effluent-dominated stream. Five locations were selected along the pollution gradient and compared with a nearby (reference) site. Cellular Energy Allocation (CEA) served as a biomarker of cellular energetics, while Scope for Growth (SFG) indicated effects on a physiological level and Tissue Condition Index and wet tissue weight/dry tissue weight ratio were used as endpoints of organismal effects. Results indicated that energy budgets at a cellular level of biological organization provided the fastest and most sensitive response and energy budgets are a relevant currency to extrapolate cellular effects to higher levels of biological organization within the exposed mussels.

Molecular and cellular mechanisms of tight junction dysfunction in the irritable bowel syndrome.

Science.gov (United States)

Cheng, Peng; Yao, Jianning; Wang, Chunfeng; Zhang, Lianfeng; Kong, Wuming

2015-09-01

The pathophysiological mechanisms of the irritable bowel syndrome (IBS), one of the most prevalent gastrointestinal disorders, are complex and have not been fully elucidated. The present study aimed to investigate the molecular and cellular mechanisms of tight junction (TJ) dysfunction in IBS. Intestinal tissues of IBS and non‑IBS patients were examined to observe cellular changes by cell chemical tracer electron microscopy and transmission electron microscopy, and intestinal claudin‑1 protein was detected by immunohistochemistry, western blot analysis and fluorescence quantitative polymerase chain reaction. Compared with the control group, TJ broadening and the tracer extravasation phenomenon were observed in the diarrhea‑predominant IBS group, and a greater number of neuroendocrine cells and mast cells filled with high‑density particles in the endocrine package pulp as well as a certain extent of vacuolization were present. The expression of claudin‑1 in diarrhea‑predominant IBS patients was decreased, while it was increased in constipation‑predominant IBS patients. In conclusion, the results of the present study indicated that changes in cellular structure and claudin‑1 levels were associated with Tjs in IBS.

Surface topography and chemistry shape cellular behavior on wide band-gap semiconductors.

Science.gov (United States)

Bain, Lauren E; Collazo, Ramon; Hsu, Shu-Han; Latham, Nicole Pfiester; Manfra, Michael J; Ivanisevic, Albena

2014-06-01

The chemical stability and electrical properties of gallium nitride make it a promising material for the development of biocompatible electronics, a range of devices including biosensors as well as interfaces for probing and controlling cellular growth and signaling. To improve the interface formed between the probe material and the cell or biosystem, surface topography and chemistry can be applied to modify the ways in which the device interacts with its environment. PC12 cells are cultured on as-grown planar, unidirectionally polished, etched nanoporous and nanowire GaN surfaces with and without a physisorbed peptide sequence that promotes cell adhesion. While cells demonstrate preferential adhesion to roughened surfaces over as-grown flat surfaces, the topography of that roughness also influences the morphology of cellular adhesion and differentiation in neurotypic cells. Addition of the peptide sequence generally contributes further to cellular adhesion and promotes development of stereotypic long, thin neurite outgrowths over alternate morphologies. The dependence of cell behavior on both the topographic morphology and surface chemistry is thus demonstrated, providing further evidence for the importance of surface modification for modulating bio-inorganic interfaces. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Cellular energy metabolism in T-lymphocytes.

Science.gov (United States)

Gaber, Timo; Strehl, Cindy; Sawitzki, Birgit; Hoff, Paula; Buttgereit, Frank

2015-01-01

Energy homeostasis is a hallmark of cell survival and maintenance of cell function. Here we focus on the impact of cellular energy metabolism on T-lymphocyte differentiation, activation, and function in health and disease. We describe the role of transcriptional and posttranscriptional regulation of lymphocyte metabolism on immune functions of T cells. We also summarize the current knowledge about T-lymphocyte adaptations to inflammation and hypoxia, and the impact on T-cell behavior of pathophysiological hypoxia (as found in tumor tissue, chronically inflamed joints in rheumatoid arthritis and during bone regeneration). A better understanding of the underlying mechanisms that control immune cell metabolism and immune response may provide therapeutic opportunities to alter the immune response under conditions of either immunosuppression or inflammation, potentially targeting infections, vaccine response, tumor surveillance, autoimmunity, and inflammatory disorders.

Genetic alterations in fatty acid transport and metabolism genes are associated with metastatic progression and poor prognosis of human cancers.

Science.gov (United States)

Nath, Aritro; Chan, Christina

2016-01-04

Reprogramming of cellular metabolism is a hallmark feature of cancer cells. While a distinct set of processes drive metastasis when compared to tumorigenesis, it is yet unclear if genetic alterations in metabolic pathways are associated with metastatic progression of human cancers. Here, we analyzed the mutation, copy number variation and gene expression patterns of a literature-derived model of metabolic genes associated with glycolysis (Warburg effect), fatty acid metabolism (lipogenesis, oxidation, lipolysis, esterification) and fatty acid uptake in >9000 primary or metastatic tumor samples from the multi-cancer TCGA datasets. Our association analysis revealed a uniform pattern of Warburg effect mutations influencing prognosis across all tumor types, while copy number alterations in the electron transport chain gene SCO2, fatty acid uptake (CAV1, CD36) and lipogenesis (PPARA, PPARD, MLXIPL) genes were enriched in metastatic tumors. Using gene expression profiles, we established a gene-signature (CAV1, CD36, MLXIPL, CPT1C, CYP2E1) that strongly associated with epithelial-mesenchymal program across multiple cancers. Moreover, stratification of samples based on the copy number or expression profiles of the genes identified in our analysis revealed a significant effect on patient survival rates, thus confirming prominent roles of fatty acid uptake and metabolism in metastatic progression and poor prognosis of human cancers.

Cellular Therapies Clinical Research Roadmap: lessons learned on how to move a cellular therapy into a clinical trial.

Science.gov (United States)

Ouseph, Stacy; Tappitake, Darah; Armant, Myriam; Wesselschmidt, Robin; Derecho, Ivy; Draxler, Rebecca; Wood, Deborah; Centanni, John M

2015-04-01

A clinical research roadmap has been developed as a resource for researchers to identify critical areas and potential pitfalls when transitioning a cellular therapy product from the research laboratory, by means of an Investigational New Drug (IND) application, into early-phase clinical trials. The roadmap describes four key areas: basic and preclinical research, resource development, translational research and Good Manufacturing Practice (GMP) and IND assembly and submission. Basic and preclinical research identifies a new therapeutic concept and demonstrates its potential value with the use of a model of the relevant disease. During resource development, the appropriate specialists and the required expertise to bring this product into the clinic are identified (eg, researchers, regulatory specialists, GMP manufacturing staff, clinicians and clinical trials staff, etc). Additionally, the funds required to achieve this goal (or a plan to procure them) are identified. In the next phase, the plan to translate the research product into a clinical-grade therapeutic is developed. Finally regulatory approval to start the trial must be obtained. In the United States, this is done by filing an IND application with the Food and Drug Administration. The National Heart, Lung and Blood Institute-funded Production Assistance for Cellular Therapies program has facilitated the transition of a variety of cellular therapy products from the laboratory into Phase1/2 trials. The five Production Assistance for Cellular Therapies facilities have assisted investigators by performing translational studies and GMP manufacturing to ensure that cellular products met release specifications and were manufactured safely, reproducibly and at the appropriate scale. The roadmap resulting from this experience is the focus of this article. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Cellular Restriction Factors of Feline Immunodeficiency Virus

Science.gov (United States)

Zielonka, Jörg; Münk, Carsten

2011-01-01

Lentiviruses are known for their narrow cell- and species-tropisms, which are determined by cellular proteins whose absence or presence either support viral replication (dependency factors, cofactors) or inhibit viral replication (restriction factors). Similar to Human immunodeficiency virus type 1 (HIV-1), the cat lentivirus Feline immunodeficiency virus (FIV) is sensitive to recently discovered cellular restriction factors from non-host species that are able to stop viruses from replicating. Of particular importance are the cellular proteins APOBEC3, TRIM5α and tetherin/BST-2. In general, lentiviruses counteract or escape their species’ own variant of the restriction factor, but are targeted by the orthologous proteins of distantly related species. Most of the knowledge regarding lentiviral restriction factors has been obtained in the HIV-1 system; however, much less is known about their effects on other lentiviruses. We describe here the molecular mechanisms that explain how FIV maintains its replication in feline cells, but is largely prevented from cross-species infections by cellular restriction factors. PMID:22069525

Cellular structures in a system of interacting particles

International Nuclear Information System (INIS)

Lev, B.I.

2009-01-01

The general description of the formation of a cellular structure in the system of interacting particles is proposed. The analytical results for possible cellular structures in the usual colloidal systems, systems of particles immersed in a liquid crystal, and gravitational systems have been presented. It is shown that the formation of a cellular structure in all systems of interacting particles at different temperatures and concentrations of particles has the same physical nature

Application of Digital Cellular Radio for Mobile Location Estimation

Directory of Open Access Journals (Sweden)

Farhat Anwar

2012-08-01

Full Text Available The capability to locate the position of mobiles is a prerequisite to implement a wide range of evolving ITS services. Radiolocation has the potential to serve a wide geographical area. This paper reports an investigation regarding the feasibility of utilizing cellular radio for the purpose of mobile location estimation. Basic strategies to be utilized for location estimation are elaborated. Two possible approaches for cellular based location estimation are investigated with the help of computer simulation. Their effectiveness and relative merits and demerits are identified. An algorithm specifically adapted for cellular environment is reported with specific features where mobiles, irrespective of their numbers, can locate their position without adversely loading the cellular system.Key Words: ITS, GSM, Cellular Radio, DRGS, GPS.

Effects of fexofenadine and hydroxyzine on brake reaction time during car-driving with cellular phone use.

Science.gov (United States)

Tashiro, Manabu; Horikawa, Etsuo; Mochizuki, Hideki; Sakurada, Yumiko; Kato, Motohisa; Inokuchi, Takatoshi; Ridout, Fran; Hindmarch, Ian; Yanai, Kazuhiko

2005-10-01

Antihistamines are a mainstay treatment for allergic rhinitis; however, many older agents cause adverse events, including sedation and central nervous system (CNS) impairment. Research has shown sedating effects of antihistamines on driving; currently, no known study has examined whether cellular phone usage while driving further compounds impairment in individuals administered antihistamines. The aim of this study was to examine this endpoint. In a randomized, double-blind, placebo-controlled, three-way crossover study, healthy volunteers received fexofenadine HCl 120 mg, hydroxyzine HCl 30 mg and placebo. Brake reaction time (BRT) was used to examine driving performance across four conditions: driving only; driving while completing simple calculations; complex calculations; and conversing on a cellular phone. Subjective sedation assessments were also conducted. Brake reaction time with and without cellular phone usage in fexofenadine-treated subjects did not differ significantly from placebo in any condition. In contrast, hydroxyzine-treated subjects were significantly more sedated and had slower BRTs, suggesting slower hazard recognition and brake application, compared with the fexofenadine and placebo groups in all conditions. Importantly, cellular phone operation was an additive factor, increasing BRTs in hydroxyzine-treated volunteers. Fexofenadine did not impair CNS function in subjects involved in a divided attention task of driving and cellular phone operation. Copyright (c) 2005 John Wiley & Sons, Ltd.

Cellular defense against singlet oxygen-induced oxidative damage by cytosolic NADP+-dependent isocitrate dehydrogenase.

Science.gov (United States)

Kim, Sun Yee; Park, Jeen-Woo

2003-03-01

Singlet oxygen (1O2) is a highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules. Recently, we have shown that NADP+-dependent isocitrate dehydrogenase is involved in the supply of NADPH needed for GSH production against cellular oxidative damage. In this study, we investigated the role of cytosolic form of NADP+-dependent isocitrate dehydrogenase (IDPc) against singlet oxygen-induced cytotoxicity by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 2.3-fold higher and 39% lower, respectively, than that in the parental cells carrying the vector alone. Upon exposure to singlet oxygen generated from photoactivated dye, the cells with low levels of IDPc became more sensitive to cell killing. Lipid peroxidation, protein oxidation, oxidative DNA damage and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly over-expressed IDPc exhibited enhanced resistance against singlet oxygen, compared to the control cells. The data indicate that IDPc plays an important role in cellular defense against singlet oxygen-induced oxidative injury.

Building mathematics cellular phone learning communities

Directory of Open Access Journals (Sweden)

Wajeeh M. Daher

2011-04-01

Full Text Available Researchers emphasize the importance of maintaining learning communities and environments. This article describes the building and nourishment of a learning community, one comprised of middle school students who learned mathematics out-of-class using the cellular phone. The building of the learning community was led by three third year pre-service teachers majoring in mathematics and computers. The pre-service teachers selected thirty 8th grade students to learn mathematics with the cellular phone and be part of a learning community experimenting with this learning. To analyze the building and development stages of the cellular phone learning community, two models of community building stages were used; first the team development model developed by Tuckman (1965, second the life cycle model of a virtual learning community developed by Garber (2004. The research findings indicate that a learning community which is centered on a new technology has five 'life' phases of development: Pre-birth, birth, formation, performing, and maturity. Further, the research finding indicate that the norms that were encouraged by the preservice teachers who initiated the cellular phone learning community resulted in a community which developed, nourished and matured to be similar to a community of experienced applied mathematicians who use mathematical formulae to study everyday phenomena.

Influence of corona charging in cellular polyethylene film

International Nuclear Information System (INIS)

Ortega Brana, Gustavo; Magraner, Francisco; Quijano, Alfredo; Llovera Segovia, Pedro

2011-01-01

Cellular polymers have recently attracted attention for their property of exhibiting a piezoelectric constant when they are electrically charged. The electrostatic charge generated in the voids by the internal discharges creates and internal macrodipole which is responsible for the piezoelectric effect. Charging by corona discharge is the most used method for cellular polymers. Many works has been published on polypropylene and polyethylene films mainly focused on the required expansion process or on the results obtained for raw cellular materials electrically activated. Our work is based on commercial polyethylene cellular films which have been physically characterized and electrically activated. The effect of thermal treatment, physical uniaxial or biaxial stretching and corona charging was investigated. The new method of corona charging improved the piezoelectric constant under other activation conditions.

Influence of corona charging in cellular polyethylene film

Energy Technology Data Exchange (ETDEWEB)

Ortega Brana, Gustavo; Magraner, Francisco; Quijano, Alfredo [Instituto Tecnologico de la Energia (ITE), Av. Juan de la Cierva 24, Parque Tecnologico de Valencia, 46980 Paterna-Valencia (Spain); Llovera Segovia, Pedro, E-mail: gustavo.ortega@ite.es [Instituto de TecnologIa Electrica - Universitat Politecnica de Valencia, Camino de Vera s/n 46022-Valencia (Spain)

2011-06-23

Cellular polymers have recently attracted attention for their property of exhibiting a piezoelectric constant when they are electrically charged. The electrostatic charge generated in the voids by the internal discharges creates and internal macrodipole which is responsible for the piezoelectric effect. Charging by corona discharge is the most used method for cellular polymers. Many works has been published on polypropylene and polyethylene films mainly focused on the required expansion process or on the results obtained for raw cellular materials electrically activated. Our work is based on commercial polyethylene cellular films which have been physically characterized and electrically activated. The effect of thermal treatment, physical uniaxial or biaxial stretching and corona charging was investigated. The new method of corona charging improved the piezoelectric constant under other activation conditions.

Cellular structures with interconnected microchannels

Science.gov (United States)

Shaefer, Robert Shahram; Ghoniem, Nasr M.; Williams, Brian

2018-01-30

A method for fabricating a cellular tritium breeder component includes obtaining a reticulated carbon foam skeleton comprising a network of interconnected ligaments. The foam skeleton is then melt-infiltrated with a tritium breeder material, for example, lithium zirconate or lithium titanate. The foam skeleton is then removed to define a cellular breeder component having a network of interconnected tritium purge channels. In an embodiment the ligaments of the foam skeleton are enlarged by adding carbon using chemical vapor infiltration (CVI) prior to melt-infiltration. In an embodiment the foam skeleton is coated with a refractory material, for example, tungsten, prior to melt infiltration.

Naringenin-loaded solid lipid nanoparticles: preparation, controlled delivery, cellular uptake, and pulmonary pharmacokinetics

Directory of Open Access Journals (Sweden)

Ji P

2016-03-01

Full Text Available Peng Ji, Tong Yu, Ying Liu, Jie Jiang, Jie Xu, Ying Zhao, Yanna Hao, Yang Qiu, Wenming Zhao, Chao WuCollege of Pharmacy, Liaoning Medical University, Jinzhou, Liaoning Province, People’s Republic of ChinaAbstract: Naringenin (NRG, a flavonoid compound, had been reported to exhibit extensive pharmacological effects, but its water solubility and oral bioavailability are only ~46±6 µg/mL and 5.8%, respectively. The purpose of this study is to design and develop NRG-loaded solid lipid nanoparticles (NRG-SLNs to provide prolonged and sustained drug release, with improved stability, involving nontoxic nanocarriers, and increase the bioavailability by means of pulmonary administration. Initially, a group contribution method was used to screen the best solid lipid matrix for the preparation of SLNs. NRG-SLNs were prepared by an emulsification and low-temperature solidification method and optimized using an orthogonal experiment approach. The morphology was examined by transmission electron microscopy, and the particle size and zeta potential were determined by photon correlation spectroscopy. The total drug content of NRG-SLNs was measured by high-performance liquid chromatography, and the encapsulation efficiency (EE was determined by Sephadex gel-50 chromatography and high-performance liquid chromatography. The in vitro NRG release studies were carried out using a dialysis bag. The best cryoprotectant to prepare NRG-SLN lyophilized powder for future structural characterization was selected using differential scanning calorimetry, powder X-ray diffraction, and Fourier transform infrared spectroscopy. The short-term stability, 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyl-tetrazolium bromide (MTT assay, cellular uptake, and pharmacokinetics in rats were studied after pulmonary administration of NRG-SLN lyophilized powder. Glycerol monostearate was selected to prepare SLNs, and the optimal formulation of NRG-SLNs was spherical in shape, with a particle

Multidimensional traveling waves in the Allen–Cahn cellular automaton

International Nuclear Information System (INIS)

Murata, Mikio

2015-01-01

Ultradiscretization is a limiting procedure transforming a given difference equation into a cellular automaton. The cellular automaton constructed by this procedure preserves the essential properties of the original equation, such as the structure of exact solutions for integrable equations. In this article, a cellular automaton analog of the multidimensional Allen–Cahn equation which is not an integrable system is constructed by the ultradiscretization. Moreover, the traveling wave solutions for the resulting cellular automaton are given. The shape, behavior and stability of the solutions in ultradiscrete systems are similar to those in continuous systems. (paper)

Design, synthesis and cellular metabolism study of 4'-selenonucleosides.

Science.gov (United States)

Yu, Jinha; Sahu, Pramod K; Kim, Gyudong; Qu, Shuhao; Choi, Yoojin; Song, Jayoung; Lee, Sang Kook; Noh, Minsoo; Park, Sunghyouk; Jeong, Lak Shin

2015-01-01

4'-seleno-homonucleosides were synthesized as next-generation nucleosides, and their cellular phosphorylation was studied to confirm the hypothesis that bulky selenium atom can sterically hinder the approach of cellular nucleoside kinase to the 5'-OH for phosphorylation. 4'-seleno-homonucleosides (n = 2), with one-carbon homologation, were synthesized through a tandem seleno-Michael addition-SN2 ring cyclization. LC-MS analysis demonstrated that they were phosphorylated by cellular nucleoside kinases, resulting in anticancer activity. The bulky selenium atom played a key role in deciding the phosphorylation by cellular nucleoside kinases. [Formula: see text].

The human ubiquitin-conjugating enzyme Cdc34 controls cellular proliferation through regulation of p27Kip1 protein levels

International Nuclear Information System (INIS)

Butz, Nicole; Ruetz, Stephan; Natt, Francois; Hall, Jonathan; Weiler, Jan; Mestan, Juergen; Ducarre, Monique; Grossenbacher, Rita; Hauser, Patrick; Kempf, Dominique; Hofmann, Francesco

2005-01-01

Ubiquitin-mediated degradation of the cyclin-dependent kinase inhibitor p27 Kip1 was shown to be required for the activation of key cyclin-dependent kinases, thereby triggering the onset of DNA replication and cell cycle progression. Although the SCF Skp2 ubiquitin ligase has been reported to mediate p27 Kip1 degradation, the nature of the human ubiquitin-conjugating enzyme involved in this process has not yet been determined at the cellular level. Here, we show that antisense oligonucleotides targeting the human ubiquitin-conjugating enzyme Cdc34 downregulate its expression, inhibit the degradation of p27 Kip1 , and prevent cellular proliferation. Elevation of p27 Kip1 protein level is found to be the sole requirement for the inhibition of cellular proliferation induced upon downregulation of Cdc34. Indeed, reducing the expression of p27 Kip1 with a specific antisense oligonucleotide is sufficient to reverse the anti-proliferative phenotype elicited by the Cdc34 antisense. Furthermore, downregulation of Cdc34 is found to specifically increase the abundance of the SCF Skp2 ubiquitin ligase substrate p27 Kip1 , but has no concomitant effect on the level of IkBα and β-catenin, which are known substrates of a closely related SCF ligase

Cellular metabolism

International Nuclear Information System (INIS)

Hildebrand, C.E.; Walters, R.A.

1977-01-01

Progress is reported on the following research projects: chromatin structure; the use of circular synthetic polydeoxynucleotides as substrates for the study of DNA repair enzymes; human cellular kinetic response following exposure to DNA-interactive compounds; histone phosphorylation and chromatin structure in cell proliferation; photoaddition products induced in chromatin by uv light; pollutants and genetic information transfer; altered RNA metabolism as a function of cadmium accumulation and intracellular distribution in cultured cells; and thymidylate chromophore destruction by water free radicals

Various cellular stress components change as the rat ages: An insight into the putative overall age-related cellular stress network.

Science.gov (United States)

Cueno, Marni E; Imai, Kenichi

2018-02-01

Cellular stress is mainly comprised of oxidative, nitrosative, and endoplasmic reticulum stresses and has long been correlated to the ageing process. Surprisingly, the age-related difference among the various components in each independent stress pathway and the possible significance of these components in relation to the overall cellular stress network remain to be clearly elucidated. In this study, we obtained blood from ageing rats upon reaching 20-, 40-, and 72-wk.-old. Subsequently, we measured representative cellular stress-linked biomolecules (H 2 O 2 , glutathione reductase, heme, NADPH, NADP, nitric oxide, GADD153) and cell signals [substance P (SP), free fatty acid, calcium, NF-κB] in either or both blood serum and cytosol. Subsequently, network analysis of the overall cellular stress network was performed. Our results show that there are changes affecting stress-linked biomolecules and cell signals as the rat ages. Additionally, based on our network analysis data, we postulate that NADPH, H 2 O 2 , GADD153, and SP are the key components and the interactions between these components are central to the overall age-related cellular stress network in the rat blood. Thus, we propose that the main pathway affecting the overall age-related cellular stress network in the rat blood would entail NADPH-related oxidative stress (involving H 2 O 2 ) triggering GADD153 activation leading to SP induction which in-turn affects other cell signals. Copyright © 2017 Elsevier Inc. All rights reserved.

Electrically heated 3D-macro cellular SiC structures for ignition and combustion application

International Nuclear Information System (INIS)

Falgenhauer, Ralf; Rambacher, Patrick; Schlier, Lorenz; Volkert, Jochen; Travitzky, Nahum; Greil, Peter; Weclas, Miroslaw

2017-01-01

Highlights: • 3D-printed macro cellular SiC structure. • Directly integrated electrically heated ignition element used in combustion reactor. • Experimental investigation of the ignition process. - Abstract: The paper describes different aspects of porous combustion reactor operation especially at cold start conditions. Under cold start conditions it is necessary to increase the internal energy of the combustion reactor, to accumulate enough energy inside its solid phase and to reach at least the ignition temperature on the reactors inner surface. The most practicable method to preheat a cold porous reactor is to use its surface as a flame holder and to apply free flame combustion as a heat source for the preheating process. This paper presents a new electrically heated ignition element, which gets integrated in a three dimensional macro-cellular SiSiC reactor structure. For the development of the ignition element it was assumed, that the element is made of the same material as the combustion reactor itself and is fully integrated within the three-dimensional macro-cellular structure of the combustion reactor. Additive manufacturing like three-dimensional (3D) printing permits the production of regular SiSiC structures with constant strut thickness and a defined current flow path. To get a controlled temperature distribution on the ignition element it is necessary to control the current density distribution in the three-dimensional macro-cellular reactor structure. The ignition element used is designed to be an electrical resistance in an electric current system, converting flowing current into heat with the goal to get the highest temperature in the ignition region (glow plug). First experiments show that the ignition element integrated in a combustion reactor exhibits high dynamics and can be heated to the temperatures much above 1000 °C in a very short time (approx. 800 ms) for current of I = 150 A.

Oxyresveratrol ameliorates nonalcoholic fatty liver disease by regulating hepatic lipogenesis and fatty acid oxidation through liver kinase B1 and AMP-activated protein kinase.

Science.gov (United States)

Lee, Ju-Hee; Baek, Su Youn; Jang, Eun Jeong; Ku, Sae Kwang; Kim, Kyu Min; Ki, Sung Hwan; Kim, Chang-Eop; Park, Kwang Il; Kim, Sang Chan; Kim, Young Woo

2018-06-01

Oxyresveratrol (OXY) is a naturally occurring polyhydroxylated stilbene that is abundant in mulberry wood (Morus alba L.), which has frequently been supplied as a herbal medicine. It has been shown that OXY has regulatory effects on inflammation and oxidative stress, and may have potential in preventing or curing nonalcoholic fatty liver disease (NAFLD). This study examined the effects of OXY on in vitro model of NAFLD in hepatocyte by the liver X receptor α (LXRα)-mediated induction of lipogenic genes and in vivo model in mice along with its molecular mechanism. OXY inhibited the LXRα agonists-mediated sterol regulatory element binding protein-1c (SREBP-1c) induction and expression of the lipogenic genes and upregulated the mRNA of fatty acid β-oxidation-related genes in hepatocytes, which is more potent than genistein and daidzein. OXY also induced AMP-activated protein kinase (AMPK) activation in a time-dependent manner. Moreover, AMPK activation by the OXY treatment helped inhibit SREBP-1c using compound C as an AMPK antagonist. Oral administration of OXY decreased the Oil Red O stained-positive areas significantly, indicating lipid droplets and hepatic steatosis regions, as well as the serum parameters, such as fasting glucose, total cholesterol, and low density lipoprotein-cholesterol in high fat diet fed-mice, as similar with orally treatment of atorvastatin. Overall, this result suggests that OXY has the potency to inhibit hepatic lipogenesis through the AMPK/SREBP-1c pathway and can be used in the development of pharmaceuticals to prevent a fatty liver. Copyright © 2018. Published by Elsevier B.V.

Role of cellular adhesions in tissue dynamics spectroscopy

Science.gov (United States)

Merrill, Daniel A.; An, Ran; Turek, John; Nolte, David

2014-02-01

Cellular adhesions play a critical role in cell behavior, and modified expression of cellular adhesion compounds has been linked to various cancers. We tested the role of cellular adhesions in drug response by studying three cellular culture models: three-dimensional tumor spheroids with well-developed cellular adhesions and extracellular matrix (ECM), dense three-dimensional cell pellets with moderate numbers of adhesions, and dilute three-dimensional cell suspensions in agarose having few adhesions. Our technique for measuring the drug response for the spheroids and cell pellets was biodynamic imaging (BDI), and for the suspensions was quasi-elastic light scattering (QELS). We tested several cytoskeletal chemotherapeutic drugs (nocodazole, cytochalasin-D, paclitaxel, and colchicine) on three cancer cell lines chosen from human colorectal adenocarcinoma (HT-29), human pancreatic carcinoma (MIA PaCa-2), and rat osteosarcoma (UMR-106) to exhibit differences in adhesion strength. Comparing tumor spheroid behavior to that of cell suspensions showed shifts in the spectral motion of the cancer tissues that match predictions based on different degrees of cell-cell contacts. The HT-29 cell line, which has the strongest adhesions in the spheroid model, exhibits anomalous behavior in some cases. These results highlight the importance of using three-dimensional tissue models in drug screening with cellular adhesions being a contributory factor in phenotypic differences between the drug responses of tissue and cells.

Cellular Factors Shape 3D Genome Landscape

Science.gov (United States)

Researchers, using novel large-scale imaging technology, have mapped the spatial location of individual genes in the nucleus of human cells and identified 50 cellular factors required for the proper 3D positioning of genes. These spatial locations play important roles in gene expression, DNA repair, genome stability, and other cellular activities.

Performance Evaluation Of Mobile Cellular Networks In Nigeria

OpenAIRE

Shoewu, O.O

2018-01-01

The aim of this paper is to evaluate the performance of mobile networks such as MTN, GLO, and ETISALAT in Nigeria and suggest ways the performance of digital cellular networks can improve to minimize some of its present short comings or limitations. This paper discusses the performance improvement of digital cellular networks. A non- CDMA cellular network is use in an overall wireless environment for the purpose of this paper. This paper also discusses the performance assessment of three mobi...

Path searching in switching networks using cellular algorithm

Energy Technology Data Exchange (ETDEWEB)

Koczy, L T; Langer, J; Legendi, T

1981-01-01

After a survey of the important statements in the paper A Mathematical Model of Path Searching in General Type Switching Networks (see IBID., vol.25, no.1, p.31-43, 1981) the authors consider the possible implementation for cellular automata of the algorithm introduced there. The cellular field used consists of 5 neighbour 8 state cells. Running times required by a traditional serial processor and by the cellular field, respectively, are compared. By parallel processing this running time can be reduced. 5 references.

Coordination of plant mitochondrial biogenesis: keeping pace with cellular requirements

Science.gov (United States)

Welchen, Elina; García, Lucila; Mansilla, Natanael; Gonzalez, Daniel H.

2014-01-01

Plant mitochondria are complex organelles that carry out numerous metabolic processes related with the generation of energy for cellular functions and the synthesis and degradation of several compounds. Mitochondria are semiautonomous and dynamic organelles changing in shape, number, and composition depending on tissue or developmental stage. The biogenesis of functional mitochondria requires the coordination of genes present both in the nucleus and the organelle. In addition, due to their central role, all processes held inside mitochondria must be finely coordinated with those in other organelles according to cellular demands. Coordination is achieved by transcriptional control of nuclear genes encoding mitochondrial proteins by specific transcription factors that recognize conserved elements in their promoter regions. In turn, the expression of most of these transcription factors is linked to developmental and environmental cues, according to the availability of nutrients, light–dark cycles, and warning signals generated in response to stress conditions. Among the signals impacting in the expression of nuclear genes, retrograde signals that originate inside mitochondria help to adjust mitochondrial biogenesis to organelle demands. Adding more complexity, several nuclear encoded proteins are dual localized to mitochondria and either chloroplasts or the nucleus. Dual targeting might establish a crosstalk between the nucleus and cell organelles to ensure a fine coordination of cellular activities. In this article, we discuss how the different levels of coordination of mitochondrial biogenesis interconnect to optimize the function of the organelle according to both internal and external demands. PMID:24409193

Coordination of plant mitochondrial biogenesis: keeping pace with cellular requirements.

Directory of Open Access Journals (Sweden)

Elina eWelchen

2014-01-01

Full Text Available Plant mitochondria are complex organelles that carry out numerous metabolic processes related with the generation of energy for cellular functions and the synthesis and degradation of several compounds. Mitochondria are semiautonomous and dynamic organelles changing in shape, number and composition depending on tissue or developmental stage. The biogenesis of functional mitochondria requires the coordination of genes present both in the nucleus and the organelle. In addition, due to their central role, all processes held inside mitochondria must be finely coordinated with those in other organelles according to cellular demands. Coordination is achieved by transcriptional control of nuclear genes encoding mitochondrial proteins by specific transcription factors that recognize conserved elements in their promoter regions. In turn, the expression of most of these transcription factors is linked to developmental and environmental cues, according to the availability of nutrients, light-dark cycles and warning signals generated in response to stress conditions. Among the signals impacting in the expression of nuclear genes, retrograde signals that originate inside mitochondria help to adjust mitochondrial biogenesis to organelle demands. Adding more complexity, several nuclear encoded proteins are dual localized to mitochondria and either chloroplasts or the nucleus. Dual targeting might establish a crosstalk between the nucleus and cell organelles to ensure a fine coordination of cellular activities. In this article, we discuss how the different levels of coordination of mitochondrial biogenesis interconnect to optimize the function of the organelle according to both internal and external demands.

Rac1 Regulates the Activity of mTORC1 and mTORC2 and Controls Cellular Size

Science.gov (United States)

Saci, Abdelhafid; Cantley, Lewis C.; Carpenter, Christopher L.

2013-01-01

SUMMARY Mammalian target of rapamycin (mTOR) is a serine/threonine kinase that exists in two separate complexes, mTORC1 and mTORC2, that function to control cell size and growth in response to growth factors, nutrients, and cellular energy levels. Low molecular weight GTP-binding proteins of the Rheb and Rag families are key regulators of the mTORC1 complex, but regulation of mTORC2 is poorly understood. Here, we report that Rac1, a member of the Rho family of GTPases, is a critical regulator of both mTORC1 and mTORC2 in response to growth-factor stimulation. Deletion of Rac1 in primary cells using an inducible-Cre/Lox approach inhibits basal and growth-factor activation of both mTORC1 and mTORC2. Rac1 appears to bind directly to mTOR and to mediate mTORC1 and mTORC2 localization at specific membranes. Binding of Rac1 to mTOR does not depend on the GTP-bound state of Rac1, but on the integrity of its C-terminal domain. This function of Rac1 provides a means to regulate mTORC1 and mTORC2 simultaneously. PMID:21474067

In vitro lipid metabolism, growth and metabolic hormone concentrations in hyperthyroid chickens.

Science.gov (United States)

Rosebrough, R W; McMurtry, J P; Vasilatos-Younken, R

1992-11-01

Indian River male broiler chickens growing from 7 to 28 d of age were fed on diets containing energy:protein values varying from 43 to 106 MJ/kg protein and containing 0 or 1 mg triiodothyronine (T3)/kg diet to study effects on growth, metabolic hormone concentrations and in vitro lipogenesis. In vitro lipid synthesis was determined in liver explants in the presence and absence of ouabain (Na+, K(+)-transporting ATPase (EC 3.6.1.37) inhibitor) to estimate the role of enzyme activity in explants synthesizing lipid. Growth and feed consumption increased (P 53 MJ/kg protein) and dietary T3 lowered (P 53 MJ/kg protein) increased (P < 0.01) lipogenesis, plasma growth hormone (GH) and decreased plasma insulin-like growth factor 1 (IGF-1). Also, T3 decreased plasma GH, IGF-1 in vitro lipogenesis. Ouabain inhibited a greater proportion of in vitro lipogenesis in those explants synthesizing fat at a high rate. Both dietary T3 and in vitro ouabain decrease lipogenesis, but, when combined, the effects are not cumulative.

Nutrient-sensing nuclear receptors PPARα and FXR control liver energy balance.

Science.gov (United States)

Preidis, Geoffrey A; Kim, Kang Ho; Moore, David D

2017-04-03

The nuclear receptors PPARα (encoded by NR1C1) and farnesoid X receptor (FXR, encoded by NR1H4) are activated in the liver in the fasted and fed state, respectively. PPARα activation induces fatty acid oxidation, while FXR controls bile acid homeostasis, but both nuclear receptors also regulate numerous other metabolic pathways relevant to liver energy balance. Here we review evidence that they function coordinately to control key nutrient pathways, including fatty acid oxidation and gluconeogenesis in the fasted state and lipogenesis and glycolysis in the fed state. We have also recently reported that these receptors have mutually antagonistic impacts on autophagy, which is induced by PPARα but suppressed by FXR. Secretion of multiple blood proteins is a major drain on liver energy and nutrient resources, and we present preliminary evidence that the liver secretome may be directly suppressed by PPARα, but induced by FXR. Finally, previous studies demonstrated a striking deficiency in bile acid levels in malnourished mice that is consistent with results in malnourished children. We present evidence that hepatic targets of PPARα and FXR are dysregulated in chronic undernutrition. We conclude that PPARα and FXR function coordinately to integrate liver energy balance.

Cellular recycling of proteins in seed dormancy alleviation and germination

Directory of Open Access Journals (Sweden)

Krystyna Oracz

2016-07-01

Full Text Available Each step of the seed-to-seed cycle of plant development including seed germination is characterized by a specific set of proteins. The continual renewal and/or replacement of these biomolecules are crucial for optimal plant adaptation. As proteins are the main effectors inside the cells, their levels need to be tightly regulated. This is partially achieved by specific proteolytic pathways via multicatalytic protease complexes defined as 20S and 26S proteasomes. In plants, the 20S proteasome is responsible for degradation of carbonylated proteins, while the 26S being a part of ubiquitin-proteasome pathway (UPP is known to be involved in proteolysis of phytohormone signaling regulators. On the other hand, the role of translational control of plant development is also well documented, especially in the context of pollen tube growth and light signaling. Despite the current progress that has been made in seed biology, the sequence of cellular events that determine if the seed can germinate or not are still far from complete understanding. The role and mechanisms of regulation of proteome composition during processes occurring in the plant’s photosynthetic tissues have been well characterized since many years, but in nonphotosynthetic seeds it has emerged as a tempting research task only since the last decade. This review discusses the recent discoveries providing insights into the role of protein turnover in seed dormancy alleviation, and germination, with a focus on the control of translation and proteasomal proteolysis. The presented novel data of translatome profiling in seeds highlighted that post-transcriptional regulation of germination results from a timely regulated initiation of translation. In addition, the importance of 26S proteasome in the degradation of regulatory elements of cellular signaling and that of the 20S complex in proteolysis of specific carbonylated proteins in hormonal- and light-dependent processes occurring in seeds is

Cyclic cellular automata in 3D

International Nuclear Information System (INIS)

Reiter, Clifford A.

2011-01-01

Highlights: → We explore the self-organization of cyclic cellular automata in 3D. → Von Neumann, Moore and two types of intermediate neighborhoods are investigated. → Random neighborhoods self organize through phases into complex nested structures. → Demons are seen to have many alternatives in 3D. - Abstract: Cyclic cellular automata in two dimensions have long been intriguing because they self organize into spirals and that behavior can be analyzed. The form for the patterns that develop is highly dependent upon the form of the neighborhood. We extend this work to three dimensional cyclic cellular automata and observe self organization dependent upon the neighborhood type. This includes neighborhood types intermediate between Von Neumann and Moore neighborhoods. We also observe that the patterns include nested shells with the appropriate forms but that the nesting is far more complex than the spirals that occur in two dimensions.

Cellular Restriction Factors of Feline Immunodeficiency Virus

Directory of Open Access Journals (Sweden)

Carsten Münk

2011-10-01

Full Text Available Lentiviruses are known for their narrow cell- and species-tropisms, which are determined by cellular proteins whose absence or presence either support viral replication (dependency factors, cofactors or inhibit viral replication (restriction factors. Similar to Human immunodeficiency virus type 1 (HIV-1, the cat lentivirus Feline immunodeficiency virus (FIV is sensitive to recently discovered cellular restriction factors from non-host species that are able to stop viruses from replicating. Of particular importance are the cellular proteins APOBEC3, TRIM5α and tetherin/BST-2. In general, lentiviruses counteract or escape their species’ own variant of the restriction factor, but are targeted by the orthologous proteins of distantly related species. Most of the knowledge regarding lentiviral restriction factors has been obtained in the HIV-1 system; however, much less is known about their effects on other lentiviruses. We describe here the molecular mechanisms that explain how FIV maintains its replication in feline cells, but is largely prevented from cross-species infections by cellular restriction factors.

47 CFR 22.925 - Prohibition on airborne operation of cellular telephones.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 2 2010-10-01 2010-10-01 false Prohibition on airborne operation of cellular... CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.925 Prohibition on airborne operation of cellular telephones. Cellular telephones installed in or carried aboard airplanes, balloons or...

[Influence of Leukodeplated Blood Transfusion on Cellular Immunity of Acute Leukemia Patients].

Science.gov (United States)

Lu, Ya-Lan; Zhang, Xin; Wang, Yu-Fang; Ke, Shan-Dong; Ke, Jin-Yong; Liu, Geng-Fu; Chen, Shi-Ming

2016-08-01

To study the influence of leukodeplated blood transfusion on cellular immunity of patients with acute leuemia, so as to provide support for application of leuko-deplated blood transfusion in clinic. A total of 100 AL patients from January 2012 to December 2015 were chosen, and were divided into 2 groups: leukodeplated blood transfusion group(50 cases) and routine blood transfusion group(RBT) as control (50 cases). The effective rate, side effects, peripheral blood T cells and expression level of TLR2 and TLR4 were compared between 2 groups. The expression levels CD3(+), CD4(+), CD8(+), CD4(+)/CD8(+) of TLR2 and TLR4 in control group were (52.18±2.14)%, （27.28±1.19）%,（24.21±1.65）%,1.22±0.18,0.62±0.04 and 0.57±0.05, respectively, after treatment; while these indicators in LdBT group were （52.18±2.14）%,（30.97±2.01）%,（27.08±1.55）%,1.39±0.24,0.91±0.06 and 0.87±0.07, respectively, and above-mentioned indicators in LdBT group were significantly higher than those in control group（P0.05）. The rate of side effects in study group was 6% (3/50), 18% (9/50) in control group, with statistically significance difference （Pblood transfusion can improve the cellular immunity of AL patients, and reduce the rate of side effects.

The cellular environment in computer simulations of radiation-induced damage to DNA

International Nuclear Information System (INIS)

Moiseenko, V.V.; Waker, A.J.; Prestwich, W.V.

1998-01-01

Radiation-induced DNA single- and double-strand breaks were modeled for 660 keV photon radiation and scavenger capacity mimicking the cellular environment. Atomistic representation of DNA in B form with a first hydration shell was utilized to model direct and indirect damage. Monte Carlo generated electron tracks were used to model energy deposition in matter and to derive initial spatial distributions of species which appear in the medium following radiolysis. Diffusion of species was followed with time, and their reactions with DNA and each other were modeled in an encounter-controlled manner. Three methods to account for hydroxyl radical diffusion in a cellular environment were tested: assumed exponential survival, time-limited modeling and modeling of reactions between hydroxyl radicals and scavengers in an encounter-controlled manner. Although the method based on modeling scavenging in an encounter-controlled manner is more precise, it requires substantially more computer resources than either the exponential or time-limiting method. Scavenger concentrations of 0.5 and 0.15 M were considered using exponential and encounter-controlled methods with reaction rate set at 3 x 10 9 dm 3 mol -1 s -1 . Diffusion length and strand break yields, predicted by these two methods for the same scavenger molarity, were different by 20%-30%. The method based on limiting time of chemistry follow-up to 10 -9 s leads to DNA damage and radical diffusion estimates similar to 0.5 M scavenger concentration in the other two methods. The difference observed in predictions made by the methods considered could be tolerated in computer simulations of DNA damage. (orig.)

The cellular environment in computer simulations of radiation-induced damage to DNA

International Nuclear Information System (INIS)

Moiseenko, V.V.; Hamm, R.N.; Waker, A.J.; Prestwich, W.V.

1988-01-01

Radiation-induced DNA single- and double-strand breaks were modeled for 660 keV photon radiation and scavenger capacity mimicking the cellular environment. Atomistic representation of DNA in B form with a first hydration shell was utilized to model direct and indirect damage. Monte Carlo generated electron tracks were used to model energy deposition in matter and to derive initial spatial distributions of species which appear in the medium following radiolysis. Diffusion of species was followed with time, and their reactions with DNA and each other were modeled in an encounter-controlled manner. Three methods to account for hydroxyl radical diffusion in cellular environment were tested: assumed exponential survival, time-limited modeling and modeling of reactions between hydroxyl radicals and scavengers in an encounter-controlled manner. Although the method based on modeling scavenging in an encounter-controlled manner is more precise, it requires substantially more computer resources than either the exponential or time-limiting method. Scavenger concentrations of 0.5 and 0.15 M were considered using exponential and encounter-controlled methods with reaction rate set at 3x10 9 dm 3 mol -1 s-1. Diffusion length and strand break yields, predicted by these two methods for the same scavenger molarity, were different by 20%-30%. The method based on limiting time of chemistry follow-up to 10 -9 s leads to DNA damage and radical diffusion estimates similar to 0.5 M scavenger concentration in the other two methods. The difference observed in predictions made by the methods considered could be tolerated in computer simulations of DNA damage. (author)

A bead-based western for high-throughput cellular signal transduction analyses

Science.gov (United States)

Treindl, Fridolin; Ruprecht, Benjamin; Beiter, Yvonne; Schultz, Silke; Döttinger, Anette; Staebler, Annette; Joos, Thomas O.; Kling, Simon; Poetz, Oliver; Fehm, Tanja; Neubauer, Hans; Kuster, Bernhard; Templin, Markus F.

2016-01-01

Dissecting cellular signalling requires the analysis of large number of proteins. The DigiWest approach we describe here transfers the western blot to a bead-based microarray platform. By combining gel-based protein separation with immobilization on microspheres, hundreds of replicas of the initial blot are created, thus enabling the comprehensive analysis of limited material, such as cells collected by laser capture microdissection, and extending traditional western blotting to reach proteomic scales. The combination of molecular weight resolution, sensitivity and signal linearity on an automated platform enables the rapid quantification of hundreds of specific proteins and protein modifications in complex samples. This high-throughput western blot approach allowed us to identify and characterize alterations in cellular signal transduction that occur during the development of resistance to the kinase inhibitor Lapatinib, revealing major changes in the activation state of Ephrin-mediated signalling and a central role for p53-controlled processes. PMID:27659302

Preliminary Investigation of the Role of Cellular Immunity in Estrous Cycle Modulation of Post-Resection Breast Cancer Spread

National Research Council Canada - National Science Library

Hrushesky, William

2002-01-01

It is hypothesized that the short term objectives of doing this proposal are to better understand which sex steroids and which cellular immune functions control post resection metastatic cancer spread...

Energy-efficient power control for OFDMA cellular networks

KAUST Repository

Sboui, Lokman; Rezki, Zouheir; Alouini, Mohamed-Slim

2016-01-01

explicit expression of the optimal power allocation to each subcarrier. We also present the power control when the transmit power is limited by power budget constraint or/and minimal rate constraint and we highlight the occurrence of some transmission

Bioinspired Cellular Structures: Additive Manufacturing and Mechanical Properties

Science.gov (United States)

Stampfl, J.; Pettermann, H. E.; Liska, R.

Biological materials (e.g., wood, trabecular bone, marine skeletons) rely heavily on the use of cellular architecture, which provides several advantages. (1) The resulting structures can bear the variety of "real life" load spectra using a minimum of a given bulk material, featuring engineering lightweight design principles. (2) The inside of the structures is accessible to body fluids which deliver the required nutrients. (3) Furthermore, cellular architectures can grow organically by adding or removing individual struts or by changing the shape of the constituting elements. All these facts make the use of cellular architectures a reasonable choice for nature. Using additive manufacturing technologies (AMT), it is now possible to fabricate such structures for applications in engineering and biomedicine. In this chapter, we present methods that allow the 3D computational analysis of the mechanical properties of cellular structures with open porosity. Various different cellular architectures including disorder are studied. In order to quantify the influence of architecture, the apparent density is always kept constant. Furthermore, it is shown that how new advanced photopolymers can be used to tailor the mechanical and functional properties of the fabricated structures.

Temporal metabolomic responses of cultured HepG2 liver cells to high fructose and high glucose exposures.

Science.gov (United States)

Meissen, John K; Hirahatake, Kristin M; Adams, Sean H; Fiehn, Oliver

2015-06-01

High fructose consumption has been implicated with deleterious effects on human health, including hyperlipidemia elicited through de novo lipogenesis. However, more global effects of fructose on cellular metabolism have not been elucidated. In order to explore the metabolic impact of fructose-containing nutrients, we applied both GC-TOF and HILIC-QTOF mass spectrometry metabolomic strategies using extracts from cultured HepG2 cells exposed to fructose, glucose, or fructose + glucose. Cellular responses were analyzed in a time-dependent manner, incubated in media containing 5.5 mM glucose + 5.0 mM fructose in comparison to controls incubated in media containing either 5.5 mM glucose or 10.5 mM glucose. Mass spectrometry identified 156 unique known metabolites and a large number of unknown compounds, which revealed metabolite changes due to both utilization of fructose and high-carbohydrate loads independent of hexose structure. Fructose was shown to be partially converted to sorbitol, and generated higher levels of fructose-1-phosphate as a precursor for glycolytic intermediates. Differentially regulated ratios of 3-phosphoglycerate to serine pathway intermediates in high fructose media indicated a diversion of carbon backbones away from energy metabolism. Additionally, high fructose conditions changed levels of complex lipids toward phosphatidylethanolamines. Patterns of acylcarnitines in response to high hexose exposure (10.5 mM glucose or glucose/fructose combination) suggested a reduction in mitochondrial beta-oxidation.

Cellular potts models multiscale extensions and biological applications

CERN Document Server

Scianna, Marco

2013-01-01

A flexible, cell-level, and lattice-based technique, the cellular Potts model accurately describes the phenomenological mechanisms involved in many biological processes. Cellular Potts Models: Multiscale Extensions and Biological Applications gives an interdisciplinary, accessible treatment of these models, from the original methodologies to the latest developments. The book first explains the biophysical bases, main merits, and limitations of the cellular Potts model. It then proposes several innovative extensions, focusing on ways to integrate and interface the basic cellular Potts model at the mesoscopic scale with approaches that accurately model microscopic dynamics. These extensions are designed to create a nested and hybrid environment, where the evolution of a biological system is realistically driven by the constant interplay and flux of information between the different levels of description. Through several biological examples, the authors demonstrate a qualitative and quantitative agreement with t...

Taming the sphinx: Mechanisms of cellular sphingolipid homeostasis.

Science.gov (United States)

Olson, D K; Fröhlich, F; Farese, R V; Walther, T C

2016-08-01

Sphingolipids are important structural membrane components of eukaryotic cells, and potent signaling molecules. As such, their levels must be maintained to optimize cellular functions in different cellular membranes. Here, we review the current knowledge of homeostatic sphingolipid regulation. We describe recent studies in Saccharomyces cerevisiae that have provided insights into how cells sense changes in sphingolipid levels in the plasma membrane and acutely regulate sphingolipid biosynthesis by altering signaling pathways. We also discuss how cellular trafficking has emerged as an important determinant of sphingolipid homeostasis. Finally, we highlight areas where work is still needed to elucidate the mechanisms of sphingolipid regulation and the physiological functions of such regulatory networks, especially in mammalian cells. This article is part of a Special Issue entitled: The cellular lipid landscape edited by Tim P. Levine and Anant K. Menon. Copyright © 2015. Published by Elsevier B.V.

Cellular computational generalized neuron network for frequency situational intelligence in a multi-machine power system.

Science.gov (United States)

Wei, Yawei; Venayagamoorthy, Ganesh Kumar

2017-09-01

To prevent large interconnected power system from a cascading failure, brownout or even blackout, grid operators require access to faster than real-time information to make appropriate just-in-time control decisions. However, the communication and computational system limitations of currently used supervisory control and data acquisition (SCADA) system can only deliver delayed information. However, the deployment of synchrophasor measurement devices makes it possible to capture and visualize, in near-real-time, grid operational data with extra granularity. In this paper, a cellular computational network (CCN) approach for frequency situational intelligence (FSI) in a power system is presented. The distributed and scalable computing unit of the CCN framework makes it particularly flexible for customization for a particular set of prediction requirements. Two soft-computing algorithms have been implemented in the CCN framework: a cellular generalized neuron network (CCGNN) and a cellular multi-layer perceptron network (CCMLPN), for purposes of providing multi-timescale frequency predictions, ranging from 16.67 ms to 2 s. These two developed CCGNN and CCMLPN systems were then implemented on two different scales of power systems, one of which installed a large photovoltaic plant. A real-time power system simulator at weather station within the Real-Time Power and Intelligent Systems (RTPIS) laboratory at Clemson, SC, was then used to derive typical FSI results. Copyright © 2017 Elsevier Ltd. All rights reserved.

Design Optimization of Irregular Cellular Structure for Additive Manufacturing

Science.gov (United States)

Song, Guo-Hua; Jing, Shi-Kai; Zhao, Fang-Lei; Wang, Ye-Dong; Xing, Hao; Zhou, Jing-Tao

2017-09-01

Irregularcellular structurehas great potential to be considered in light-weight design field. However, the research on optimizing irregular cellular structures has not yet been reporteddue to the difficulties in their modeling technology. Based on the variable density topology optimization theory, an efficient method for optimizing the topology of irregular cellular structures fabricated through additive manufacturing processes is proposed. The proposed method utilizes tangent circles to automatically generate the main outline of irregular cellular structure. The topological layoutof each cellstructure is optimized using the relative density informationobtained from the proposed modified SIMP method. A mapping relationship between cell structure and relative densityelement is builtto determine the diameter of each cell structure. The results show that the irregular cellular structure can be optimized with the proposed method. The results of simulation and experimental test are similar for irregular cellular structure, which indicate that the maximum deformation value obtained using the modified Solid Isotropic Microstructures with Penalization (SIMP) approach is lower 5.4×10-5 mm than that using the SIMP approach under the same under the same external load. The proposed research provides the instruction to design the other irregular cellular structure.

Elastomeric Cellular Structure Enhanced by Compressible Liquid Filler

Science.gov (United States)

Sun, Yueting; Xu, Xiaoqing; Xu, Chengliang; Qiao, Yu; Li, Yibing

2016-05-01

Elastomeric cellular structures provide a promising solution for energy absorption. Their flexible and resilient nature is particularly relevant to protection of human bodies. Herein we develop an elastomeric cellular structure filled with nanoporous material functionalized (NMF) liquid. Due to the nanoscale infiltration in NMF liquid and its interaction with cell walls, the cellular structure has a much enhanced mechanical performance, in terms of loading capacity and energy absorption density. Moreover, it is validated that the structure is highly compressible and self-restoring. Its hyper-viscoelastic characteristics are elucidated.

Cellular defense against UVB-induced phototoxicity by cytosolic NADP+-dependent isocitrate dehydrogenase

International Nuclear Information System (INIS)

Jo, Seung-Hee; Lee, So-Hyun; Suk Chun, Hang; Min Lee, Su; Koh, Ho-Jin; Lee, Sung-Eun; Chun, Jang-Soo; Park, Jeen-Woo; Huh, Tae-Lin

2002-01-01

Ultraviolet (UV) radiation is known as a major cause of skin photoaging and photocarcinogenesis. Many harmful effects of UV radiation are associated with the generation of reactive oxygen species. Recently, we have shown that NADP + -dependent isocitrate dehydrogenase is involved in the supply of NADPH needed for GSH production against cellular oxidative damage. In this study we investigated the role of cytosolic form of NADP + -dependent isocitrate dehydrogenase (IDPc) against UV radiation-induced cytotoxicity by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 2.3-fold higher and 39% lower, respectively, than that in the parental cells carrying the vector alone. Upon exposure to UVB (312 nm), the cells with low levels of IDPc became more sensitive to cell killing. Lipid peroxidation, protein oxidation, oxidative DNA damage, and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly overexpressed IDPc exhibited enhanced resistance against UV radiation, compared to the control cells. The data indicate that IDPc plays an important role in cellular defense against UV radiation-induced oxidative injury

Cellular defense against UVB-induced phototoxicity by cytosolic NADP(+)-dependent isocitrate dehydrogenase.

Science.gov (United States)

Jo, Seung-Hee; Lee, So-Hyun; Chun, Hang Suk; Lee, Su Min; Koh, Ho-Jin; Lee, Sung-Eun; Chun, Jang-Soo; Park, Jeen-Woo; Huh, Tae-Lin

2002-03-29

Ultraviolet (UV) radiation is known as a major cause of skin photoaging and photocarcinogenesis. Many harmful effects of UV radiation are associated with the generation of reactive oxygen species. Recently, we have shown that NADP(+)-dependent isocitrate dehydrogenase is involved in the supply of NADPH needed for GSH production against cellular oxidative damage. In this study we investigated the role of cytosolic form of NADP(+)-dependent isocitrate dehydrogenase (IDPc) against UV radiation-induced cytotoxicity by comparing the relative degree of cellular responses in three different NIH3T3 cells with stable transfection with the cDNA for mouse IDPc in sense and antisense orientations, where IDPc activities were 2.3-fold higher and 39% lower, respectively, than that in the parental cells carrying the vector alone. Upon exposure to UVB (312 nm), the cells with low levels of IDPc became more sensitive to cell killing. Lipid peroxidation, protein oxidation, oxidative DNA damage, and intracellular peroxide generation were higher in the cell-line expressing the lower level of IDPc. However, the cells with the highly overexpressed IDPc exhibited enhanced resistance against UV radiation, compared to the control cells. The data indicate that IDPc plays an important role in cellular defense against UV radiation-induced oxidative injury. (c)2002 Elsevier Science (USA).

Common Genetic Variation In Cellular Transport Genes and Epithelial Ovarian Cancer (EOC) Risk

DEFF Research Database (Denmark)

Chornokur, Ganna; Lin, Hui-Yi; Tyrer, Jonathan P

2015-01-01

. As DNA damage and uncontrolled proliferation are hallmarks of cancer, including epithelial ovarian cancer (EOC), we hypothesized that inherited variation in the cellular transport genes contributes to EOC risk. METHODS: In total, DNA samples were obtained from 14,525 case subjects with invasive EOC......BACKGROUND: Defective cellular transport processes can lead to aberrant accumulation of trace elements, iron, small molecules and hormones in the cell, which in turn may promote the formation of reactive oxygen species, promoting DNA damage and aberrant expression of key regulatory cancer genes...... and from 23,447 controls from 43 sites in the Ovarian Cancer Association Consortium (OCAC). Two hundred seventy nine SNPs, representing 131 genes, were genotyped using an Illumina Infinium iSelect BeadChip as part of the Collaborative Oncological Gene-environment Study (COGS). SNP analyses were conducted...

33 CFR 183.516 - Cellular plastic used to encase fuel tanks.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Cellular plastic used to encase....516 Cellular plastic used to encase fuel tanks. (a) Cellular plastic used to encase metallic fuel...-polyurethane cellular plastic used to encase metallic fuel tanks must have a compressive strength of at least...

1024-Pixel CMOS Multimodality Joint Cellular Sensor/Stimulator Array for Real-Time Holistic Cellular Characterization and Cell-Based Drug Screening.

Science.gov (United States)

Park, Jong Seok; Aziz, Moez Karim; Li, Sensen; Chi, Taiyun; Grijalva, Sandra Ivonne; Sung, Jung Hoon; Cho, Hee Cheol; Wang, Hua

2018-02-01

This paper presents a fully integrated CMOS multimodality joint sensor/stimulator array with 1024 pixels for real-time holistic cellular characterization and drug screening. The proposed system consists of four pixel groups and four parallel signal-conditioning blocks. Every pixel group contains 16 × 16 pixels, and each pixel includes one gold-plated electrode, four photodiodes, and in-pixel circuits, within a pixel footprint. Each pixel supports real-time extracellular potential recording, optical detection, charge-balanced biphasic current stimulation, and cellular impedance measurement for the same cellular sample. The proposed system is fabricated in a standard 130-nm CMOS process. Rat cardiomyocytes are successfully cultured on-chip. Measured high-resolution optical opacity images, extracellular potential recordings, biphasic current stimulations, and cellular impedance images demonstrate the unique advantages of the system for holistic cell characterization and drug screening. Furthermore, this paper demonstrates the use of optical detection on the on-chip cultured cardiomyocytes to real-time track their cyclic beating pattern and beating rate.

Cellular Signaling in Health and Disease

CERN Document Server

Beckerman, Martin

2009-01-01

In today’s world, three great classes of non-infectious diseases – the metabolic syndromes (such as type 2 diabetes and atherosclerosis), the cancers, and the neurodegenerative disorders – have risen to the fore. These diseases, all associated with increasing age of an individual, have proven to be remarkably complex and difficult to treat. This is because, in large measure, when the cellular signaling pathways responsible for maintaining homeostasis and health of the body become dysregulated, they generate equally stable disease states. As a result the body may respond positively to a drug, but only for a while and then revert back to the disease state. Cellular Signaling in Health and Disease summarizes our current understanding of these regulatory networks in the healthy and diseased states, showing which molecular components might be prime targets for drug interventions. This is accomplished by presenting models that explain in mechanistic, molecular detail how a particular part of the cellular sign...

Design, Development and Evaluation of a Pneumatic Seeder for Automatic Planting of Seeds in Cellular Trays

Directory of Open Access Journals (Sweden)

E Movahedi

2014-04-01

Full Text Available For planting fine seeds in cellular trays, an automatic pneumatic seeder was designed, constructed and evaluated. CATIA software was used to design and analysis the system parts of the seeder. Different parts of the seeder, including vibrating seed hopper, vacuum boom, seed picking nozzles, seed tube, pneumatic system and electronic control unit for automation of the seeder, were designed and constructed. The area of nozzle orifice was used to calculate the required pressure of nozzle tip. The seeder was evaluated using two sizes of trays. Experiments were performed with five replications and the error of planting the seeds in the 105 and 390-cellular trays were 1.9 and 0.46 percent, respectively. The time of planting for 105 and 390 cellular trays reduced from 20 min (for manual seeding to 35 s and from 90 min to 160 s, respectively.

Driver hand-held cellular phone use: a four-year analysis.

Science.gov (United States)

Eby, David W; Vivoda, Jonathon M; St Louis, Renée M

2006-01-01

The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard.

Mechanisms and circumvention of cellular resistance to cisplatin.

NARCIS (Netherlands)

Hospers, Geesiena Alberdina Petronella

1989-01-01

Cisplatin (CDDP) is an active cytostatic agent. A limitation to its effectiveness initially or appearing during cystatic treatment is the occurrence of resistance. This thesis describes mechanisms wich are responsible for acquired cellular CDDP resistance. To investigate cellular CDDP resistance, a

HPV integration hijacks and multimerizes a cellular enhancer to generate a viral-cellular super-enhancer that drives high viral oncogene expression

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Redmond, Catherine J.; Dooley, Katharine E.; Fu, Haiqing; Gillison, Maura L.; Akagi, Keiko; Symer, David E.; Aladjem, Mirit I.

2018-01-01

Integration of human papillomavirus (HPV) genomes into cellular chromatin is common in HPV-associated cancers. Integration is random, and each site is unique depending on how and where the virus integrates. We recently showed that tandemly integrated HPV16 could result in the formation of a super-enhancer-like element that drives transcription of the viral oncogenes. Here, we characterize the chromatin landscape and genomic architecture of this integration locus to elucidate the mechanisms that promoted de novo super-enhancer formation. Using next-generation sequencing and molecular combing/fiber-FISH, we show that ~26 copies of HPV16 are integrated into an intergenic region of chromosome 2p23.2, interspersed with 25 kb of amplified, flanking cellular DNA. This interspersed, co-amplified viral-host pattern is frequent in HPV-associated cancers and here we designate it as Type III integration. An abundant viral-cellular fusion transcript encoding the viral E6/E7 oncogenes is expressed from the integration locus and the chromatin encompassing both the viral enhancer and a region in the adjacent amplified cellular sequences is strongly enriched in the super-enhancer markers H3K27ac and Brd4. Notably, the peak in the amplified cellular sequence corresponds to an epithelial-cell-type specific enhancer. Thus, HPV16 integration generated a super-enhancer-like element composed of tandem interspersed copies of the viral upstream regulatory region and a cellular enhancer, to drive high levels of oncogene expression. PMID:29364907

Alleviate Cellular Congestion Through Opportunistic Trough Filling

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Yichuan Wang

2014-04-01

Full Text Available The demand for cellular data service has been skyrocketing since the debut of data-intensive smart phones and touchpads. However, not all data are created equal. Many popular applications on mobile devices, such as email synchronization and social network updates, are delay tolerant. In addition, cellular load varies significantly in both large and small time scales. To alleviate network congestion and improve network performance, we present a set of opportunistic trough filling schemes that leverage the time-variation of network congestion and delay-tolerance of certain traffic in this paper. We consider average delay, deadline, and clearance time as the performance metrics. Simulation results show promising performance improvement over the standard schemes. The work shed lights on addressing the pressing issue of cellular overload.

[Effects of sub-micro emulsion composition on cellular disposition of incorporated lipophilic drug].

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Sun, Xiao-Yi; Xiang, Zhi-Qiang; Wu, Shuo; Lv, Yuan-Yuan; Liang, Wen-Quan

2013-09-01

To investigate the effects of sub-micro emulsion composition on cellular uptake and disposition of incorporated lipophilic drug. Sub-micro emulsions containing 10 % oil, 1.2 % lecithin and 2.25 % glycerol were prepared, and the fluorescent agent coumarin 6 was used as a model drug. The effects of oil types, co-surfactants and cationic lipid on uptake and elimination kinetics of 6-coumarin in HeLa cells were studied. The uptake mechanism of sub-micro emulsions was further investigated. Oil type and Tweens had no influence on the cellular uptake. Modifications of surfactants with Span series increased the cellular influx, among which Span 20 with hydrophilic-lipophilic balance (HLB) value of 8.6 was the best enhancer. The intracellular drug level reached up to (46.09 ± 1.98)ng/μg protein which had significant difference with control group [(38.54 ± 0.34)ng/μg protein]. The positively charged emulsions significantly increased the uptake rate constant and elimination rate constant which were 4 times and 1.5 times of those in anionic groups, respectively. The uptake enhancement was also observed in cationic emulsions, cellular concentrations at plateau were (42.73 ± 0.84)ng/μg protein, which was about 3 times of that in anionic emulsions [(15.71 ± 0.74)ng/μg protein], when extracellular drug concentration kept at 100 ng/ml. Cationic emulsions delivered the payload mainly by direct drug transfer to contacted cells, while the negative ones depended on both drug passive diffusion and clathrin-mediated endocytosis of drug containing oil droplets which accounted for 20% of the intracellular drug. Interfacial characteristic of sub-micro emulsions such as co-surfactants HLB as well as zeta potentials can influence lipophilic drug both in cellular uptake and elimination.

Single-cell-based system to monitor carrier driven cellular auxin homeostasis

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2013-01-01

Background Abundance and distribution of the plant hormone auxin play important roles in plant development. Besides other metabolic processes, various auxin carriers control the cellular level of active auxin and, hence, are major regulators of cellular auxin homeostasis. Despite the developmental importance of auxin transporters, a simple medium-to-high throughput approach to assess carrier activities is still missing. Here we show that carrier driven depletion of cellular auxin correlates with reduced nuclear auxin signaling in tobacco Bright Yellow-2 (BY-2) cell cultures. Results We developed an easy to use transient single-cell-based system to detect carrier activity. We use the relative changes in signaling output of the auxin responsive promoter element DR5 to indirectly visualize auxin carrier activity. The feasibility of the transient approach was demonstrated by pharmacological and genetic interference with auxin signaling and transport. As a proof of concept, we provide visual evidence that the prominent auxin transport proteins PIN-FORMED (PIN)2 and PIN5 regulate cellular auxin homeostasis at the plasma membrane and endoplasmic reticulum (ER), respectively. Our data suggest that PIN2 and PIN5 have different sensitivities to the auxin transport inhibitor 1-naphthylphthalamic acid (NPA). Also the putative PIN-LIKES (PILS) auxin carrier activity at the ER is insensitive to NPA in our system, indicating that NPA blocks intercellular, but not intracellular auxin transport. Conclusions This single-cell-based system is a useful tool by which the activity of putative auxin carriers, such as PINs, PILS and WALLS ARE THIN1 (WAT1), can be indirectly visualized in a medium-to-high throughput manner. Moreover, our single cell system might be useful to investigate also other hormonal signaling pathways, such as cytokinin. PMID:23379388

Single Cell Force Spectroscopy for Quantification of Cellular Adhesion on Surfaces

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Christenson, Wayne B.

Cell adhesion is an important aspect of many biological processes. The atomic force microscope (AFM) has made it possible to quantify the forces involved in cellular adhesion using a technique called single cell force spectroscopy (SCFS). AFM based SCFS offers versatile control over experimental conditions for probing directly the interaction between specific cell types and specific proteins, surfaces, or other cells. Transmembrane integrins are the primary proteins involved in cellular adhesion to the extra cellular matix (ECM). One of the chief integrins involved in the adhesion of leukocyte cells is alpha Mbeta2 (Mac-1). The experiments in this dissertation quantify the adhesion of Mac-1 expressing human embryonic kidney (HEK Mac-1), platelets, and neutrophils cells on substrates with different concentrations of fibrinogen and on fibrin gels and multi-layered fibrinogen coated fibrin gels. It was shown that multi-layered fibrinogen reduces the adhesion force of these cells considerably. A novel method was developed as part of this research combining total internal reflection microscopy (TIRFM) with SCFS allowing for optical microscopy of HEK Mac-1 cells interacting with bovine serum albumin (BSA) coated glass after interacting with multi-layered fibrinogen. HEK Mac-1 cells are able to remove fibrinogen molecules from the multi-layered fibrinogen matrix. An analysis methodology for quantifying the kinetic parameters of integrin-ligand interactions from SCFS experiments is proposed, and the kinetic parameters of the Mac-1 fibrinogen bond are quantified. Additional SCFS experiments quantify the adhesion of macrophages and HEK Mac-1 cells on functionalized glass surfaces and normal glass surfaces. Both cell types show highest adhesion on a novel functionalized glass surface that was prepared to induce macrophage fusion. These experiments demonstrate the versatility of AFM based SCFS, and how it can be applied to address many questions in cellular biology offering

WetA bridges cellular and chemical development in Aspergillus flavus.

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Ming-Yueh Wu

Full Text Available Bridging cellular reproduction and survival is essential for all life forms. Aspergillus fungi primarily reproduce by forming asexual spores called conidia, whose formation and maturation is governed by the central genetic regulatory circuit BrlA→AbaA→WetA. Here, we report that WetA is a multi-functional regulator that couples spore differentiation and survival, and governs proper chemical development in Aspergillus flavus. The deletion of wetA results in the formation of conidia with defective cell walls and no intra-cellular trehalose, leading to reduced stress tolerance, a rapid loss of viability, and disintegration of spores. WetA is also required for normal vegetative growth, hyphal branching, and production of aflatoxins. Targeted and genome-wide expression analyses reveal that WetA exerts feedback control of brlA and that 5,700 genes show altered mRNA levels in the mutant conidia. Functional category analyses of differentially expressed genes in ΔwetA RNA-seq data indicate that WetA contributes to spore integrity and maturity by properly regulating the metabolic pathways of trehalose, chitin, α-(1,3-glucan, β-(1,3-glucan, melanin, hydrophobins, and secondary metabolism more generally. Moreover, 160 genes predicted to encode transcription factors are differentially expressed by the absence of wetA, suggesting that WetA may play a global regulatory role in conidial development. Collectively, we present a comprehensive model for developmental control that bridges spore differentiation and survival in A. flavus.