WorldWideScience
 
 
1

Aldehyde Oxidase and Xanthine Dehydrogenase in a flacca Tomato Mutant with Deficient Abscisic Acid and Wilty Phenotype1  

UK PubMed Central (United Kingdom)

The flacca tomato (Lycopersicon esculentum) mutant displays a wilty phenotype as a result of abscisic acid (ABA) deficiency. The Mo cofactor (MoCo)-containing aldehyde...Full Text Available

1999-06-01

2

Antioxidant action of antimalarials.  

UK PubMed Central (United Kingdom)

The effects of antimalarials, chloroquine and quinacrine, on the generation of reactive oxygen species were examined both in polymorphonuclear leucocytes and in the xanthine-xanthine oxidase system....Full Text Available

1986-03-01

5

Knock limitations of methane-air mixtures in a turbocharged dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

Knock limitations are investigated using natural gas, with diesel pilot ignition, as a fuel for the 3406 DI-TA Caterpillar diesel engine. Thermodynamic properties at TDC are generated by computer and compared with experimental results. Exhaust emissions are analyzed. A comparison is made of dual-fuel operation relative to diesel. Observations are made to determine the onset of knock. The onset of knock is characterized as a function of engine speed, load, inlet manifold temperature, and air-fuel ratio (A/F). The conditions at the inset of knock are determined using cylinder pressure data. The most efficient operating range is determined with knock avoidance as a prime parameter.

1987-01-01

6

Ignition timing control apparatus with knock sensor  

Energy Technology Data Exchange (ETDEWEB)

In an ignition timing control apparatus for controlling the ignition timing of each cylinder in order to reduce knock generation in a multi-cylinder engine, a lag-angle correction is made for the ignition timing of a cylinder in which a knock is generated and at the same time, a slight lag-angle correction is made for the ignition timing of the other cylinders in which no knock is generated. When the operating condition of engine is rapidly changed for example, under the condition in which knock is liable to occur in all cylinders as at rapid acceleration time, a lag-angle correction is made by the same amount as in the knock generating cylinder, for the ignition timing of cylinders in which no knock is generated. When no knock is generated for a predetermined time, a lead-angle correction is made for the ignition timing subjected to the ...

1984-05-01

7

Effect of a diluent on the performance of a hydrogen-diesel dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

Earlier work carried out on the hydrogen-diesel dual-fuel engine indicates that knock sets in when the inducted hydrogen exceeds about 60% of input energy with a pilot quantity of 30% of full load diesel amount. Some of the findings of an investigation into knock-free performance of a hydrogen-diesel dual-fuel engine with the addition of a diluent-carbon dioxide are presented. The effects of carbon dioxide on the suppression of knocking in the hydrogen-diesel dual-fuel engine and on the improvement in the knock limited power output are described.

1986-11-01

8

Regulation of Glutamate Dehydrogenases in nit-2 and am Mutants of Neurospora crassa  

UK PubMed Central (United Kingdom)

The regulation of the glutamate dehydrogenases was investigated in wild-type Neurospora crassa and two classes of mutants altered in the assimilation of inorganic nitrogen, as either...Full Text Available

1979-03-01

9

Iodination of glyceraldehyde 3-phosphate dehydrogenase  

UK PubMed Central (United Kingdom)

1. A high degree of homology in the positions of tyrosine residues in glyceraldehyde 3-phosphate dehydrogenase from lobster and pig muscle, and from yeast, prompted an examination of the reactivity...Full Text Available

1970-09-01

10

Sensitivity of dual fuel engine combustion and knocking limits to gaseous fuel composition  

International Nuclear Information System (INIS)

Combustion noise, knock and ignition limits data are measured and presented for a dual fuel engine running on dual fuels of Diesel and three gaseous fuels separately. The gaseous fuels used are liquefied petroleum gas, pure methane and compressed natural gas mixture. The maximum pressure rise rate during combustion is presented as a measure of combustion noise, and the knocking and ignition limits are presented as torque output at the onset of knocking and ignition failure. Experimental investigation on the dual fuel engine revealed the noise generated from combustion, knocking and ignition limits for all gases at different design and operating conditions. A Ricardo E6 Diesel version engine is converted to run on dual fuel of Diesel and the tested gaseous fuel and is used throughout the work. The engine is fully computerized, and the cylinder pressure data, crank angle data and engine operating ...

2004-02-01

11

Ignition timing control apparatus for internal combustion engine  

Energy Technology Data Exchange (ETDEWEB)

An ignition timing control apparatus is described for an internal combustion engine having a reference ignition timing comprising: sensing means for sensing vibrations including knocks of the engine; knock signal deriving means for deriving knock signals from the output of the sensing means; correction magnitude determining means for determining from the knock signals derived by the knock signal deriving means of ignition timing correction magnitude for suppressing the occurrence of knock; displacement magnitude determining means for determining from at least one of an output of the knock signal deriving means and an output of the correction magnitude determining means as a displacement magnitude for the reference ignition timing corresponding to the octane rating of a fuel used in the engine; and ignition timing determining means for ...

1986-06-17

14

Role of adenosine in regulating glucose uptake during contractions and hypoxia in rat skeletal muscle  

UK PubMed Central (United Kingdom)

The effect of A1-adenosine receptor antagonism via 8-cyclopentyl-1,3-dipropyl-xanthine (CPDPX) on the stimulation of skeletal muscle glucose uptake by...Full Text Available

1999-02-15

15

Characterization of the xanthine-binding site on R/sub a/ and R/sub i/ subtypes of the adenosine receptor  

Energy Technology Data Exchange (ETDEWEB)

Methylxanthines and their derivatives are antagonists at cell surface adenosine receptors. They report here a systematic study of xanthine structure-activity relationships which compares potency at two adenosine receptor subtypes, R/sub a/ and R/sub i/. Adenylate cyclase stimulation (R/sub a/ in platelet membranes) and inhibition (R/sub i/ in adipocyte membranes) were used as models of receptor activation. K/sub i/ values were obtained by Schild analysis. The orders of potency of the xanthines to attenuate the effects of adenosine analogues were similar to those previously reported. Earlier work utilizing radioligand binding (R/sub i/ and (/sup 3/H) cAMP formation (R/sub a/) claimed that IIX and PACPX are at least 10 and 400 fold, respectively, more potent at R/sub i/ than at R/sub a/. However, in their assays which utilize modulation of receptor-coupled adenylate cyclase, the xanthines show little specificity for either ...

1986-05-01

16

Spectral studies of intermediate species formed in one-electron reactions of bovine liver catalase at room and low temperatures. A comparison with peroxidase reactions  

Energy Technology Data Exchange (ETDEWEB)

The reactions of native bovine catalase with superoxide and solvated electrons have been investigated using three different methods for generating these reducing substrates: [gamma]-radiolysis of oxygenated or deaerated buffer solutions in the presence of an OH radical scavenger; either xanthine or acetaldehyde with xanthine oxidase; and low-temperature (77 K) [gamma]-radiolysis of buffered ethylene glycol/water solutions with subsequent annealing of samples at 183 K. (Author).

1992-11-01

17

Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor  

International Nuclear Information System (INIS)

To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3 mg/kg, and 1, 3 and 10 mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain differences were examined. FYX-051-induced increases in plasma xanthine concentrations were higher in SD rats than in F344 rats, suggesting more remarkable effects ...

2006-12-15

18

Two tandemly linked identical genes code for the glycosomal glyceraldehyde-phosphate dehydrogenase in Trypanosoma brucei.  

UK PubMed Central (United Kingdom)

Trypanosoma brucei contains two isoenzymes for glyceraldehyde-phosphate dehydrogenase (GAPDH); one enzyme resides in a microbody-like organelle, the glycosome, the other one is found in the cytosol....Full Text Available

1986-05-01

19

Trypanosoma cruzi glycosomal glyceraldehyde-3-phosphate dehydrogenase does not conform to the 'hotspot' topogenic signal model.  

UK PubMed Central (United Kingdom)

The genes which encode glycosomal glyceraldehyde-phosphate dehydrogenase (gGAPDH) of Trypanosoma cruzi are arranged as a tandemly repeated pair on a single chromosome and are identical at the level...Full Text Available

1990-09-01

20

The prosthetic group of methanol dehydrogenase. Purification and some of its properties.  

UK PubMed Central (United Kingdom)

Methanol dehydrogenases isolated from bacteria belonging to different classes of methylotrophs contain the same prosthetic group. A procedure for its purification from whole cells is given. The reduced...Full Text Available

1980-04-01

 
 
 
 
21

The comparative structure of mammalian glyceraldehyde 3-phosphate dehydrogenase  

UK PubMed Central (United Kingdom)

1. The amino acid sequences around the thiol groups of glyceraldehyde 3-phosphate dehydrogenase from badger and monkey skeletal muscle were compared with the sequences around the thiol groups in the...Full Text Available

1969-01-01

22

The Mitochondrial Isovaleryl-Coenzyme A Dehydrogenase of Arabidopsis Oxidizes Intermediates of Leucine and Valine Catabolism1  

UK PubMed Central (United Kingdom)

We recently identified a cDNA encoding a putative isovaleryl-coenzyme A (CoA) dehydrogenase in Arabidopsis (AtIVD). In animals, this homotetrameric enzyme is located in mitochondria and catalyzes the...Full Text Available

2001-06-01

23

Peripartal changes in serum alkaline phosphatase activity and lactate dehydrogenase activity in dairy cows.  

UK PubMed Central (United Kingdom)

Peripartal serum alkaline phosphatase activity and lactate dehydrogenase activity were measured in 30 dairy cows in order to examine the association between retained fetal membranes and enzyme activity....Full Text Available

1987-10-01

24

Iodination of glyceraldehyde 3-phosphate dehydrogenase from Bacillus stearothermophilus.  

UK PubMed Central (United Kingdom)

The reaction of iodine with glyceraldehyde 3-phosphate dehydrogenase from Bacillus stearothermophilus was investigated. The active-site thiol group of the cysteine residue homologous with cysteine-149...Full Text Available

1976-06-01

25

Inhibition of lactate dehydrogenase A induces oxidative stress and inhibits tumor progression  

UK PubMed Central (United Kingdom)

As the result of genetic alterations and tumor hypoxia, many cancer cells avidly take up glucose and generate lactate through lactate dehydrogenase A (LDHA), which is encoded by a target gene of c-Myc...Full Text Available

2010-02-02

26

Identification and Characterization of Retinoid-Active Short-Chain Dehydrogenases/Reductases in Drosophila melanogaster  

UK PubMed Central (United Kingdom)

BackgroundIn chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid...Full Text Available

2009-10-01

27

Formate Dehydrogenase of Clostridium thermoaceticum: Incorporation of Selenium-75, and the Effects of Selenite, Molybdate, and Tungstate on the Enzyme  

UK PubMed Central (United Kingdom)

The formation of the nicotinamide adenine dinucleotide phosphate-dependent formate dehydrogenase in Clostridium thermoaceticum is stimulated by the presence of molybdate and selenite...Full Text Available

1973-11-01

28

Defects in succinate dehydrogenase in gastrointestinal stromal tumors lacking KIT and PDGFRA mutations  

UK PubMed Central (United Kingdom)

Carney-Stratakis syndrome, an inherited condition predisposing affected individuals to gastrointestinal stromal tumor (GIST) and paraganglioma, is caused by germline mutations in succinate dehydrogenase...Full Text Available

2011-01-04

29

Complete sequence of the chicken glyceraldehyde-3-phosphate dehydrogenase gene.  

UK PubMed Central (United Kingdom)

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an evolutionarily conserved glycolytic enzyme, is constitutively expressed in most cell types yet is induced to high levels during the development of...Full Text Available

1985-03-01

30

Cellobiose dehydrogenase from Phanerochaete chrysosporium is encoded by two allelic variants.  

UK PubMed Central (United Kingdom)

The complete nucleotide sequences of two alleles of cellobiose dehydrogenase, cdh-1 (3,627 bp) and cdh-2 (3,623 bp), from Phanerochaete chrysosporium OGC101 are reported. The nucleotide sequences of...Full Text Available

1997-02-01

31

Water induction studies in a hydrogen-diesel dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

Power output of a hydrogen-diesel dual-fuel engine is limited by the onset of knock as the percentage of heat input derived from hydrogen increased beyond a certain limit. Earlier work carried out at the Internal Combustion Engines Laboratory, Indian Institute of Technology, Madras, indicates that this knock sets in when the induced hydrogen exceeds about 60% of input energy at a pilot diesel quantity of 30% of full load diesel amount. At higher rates of hydrogen induction, the richer hydrogen-air mixture is more prone to knocking. Hardly any information is available on the possibilities of improving the knock limited power output of a hydrogen-diesel dual-fuel engine. Water can serve as a powerful internal coolant in decreasing the unburned mixture temperature because of its high latent heat. This paper presents the results of our investigation on improving the knock limited power ...

1987-01-01

32

Modulation of gene expression in differentiating 3T3 - L1 preadipocytes  

Energy Technology Data Exchange (ETDEWEB)

3T3 - L1 cells can be induced to differentiate by exposing cell culture to a medium containing 3-isobutyl-1-methyl-xanthine together with insulin and dexamethasone. They have observed that oxalomalate (OMA) which inhibits aconitase thus blocking the citric cycle, also favours differentiation to adipocytes leading to fatty acids accumulation and increased synthesis of specific proteins. They compared the effects of 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone and OMA on the steady-state levels of mRNA of c / EBP, H-ferritin and aconitase / IRE-BP. OMA does not affect the steady-state mRNA amount of C / EBP, H-ferritin and aconitase / IRE-BP but the 3-isobutyl-1-methyl-xanthine-insulin-dexamethasone mixture is able to induce a five-fold increase of mRNA levels for aconitase / IRE-BP. This is the first finding correlating iron metabolism to adipocyte differentiation. Further studies will clarify a possible role for the ...

1997-12-31

33

Strain differences in the responsiveness between Sprague-Dawley and Fischer rats to nephropathy induced by FYX-051, a xanthine oxidoreductase inhibitor  

British Library Electronic Table of Contents (United Kingdom)

To determine a rat strain appropriate for carcinogenicity testing of FYX-051, a xanthine oxidoreductase inhibitor, we performed a 4-week oral toxicity study by administering 0.3, 1 and 3?mg/kg, and 1, 3 and 10?mg/kg of FYX-051 to male Sprague-Dawley (SD) and Fischer (F344) rats, respectively. Histopathology revealed that the degree of FYX-051-induced nephropathy was 3-fold stronger in SD rats than in F344 rats. Our previous study demonstrated that the key factor of species differences in FYX-051-induced nephropathy is purine metabolism. This observation led us to examine the involvement of purine metabolism in differences among two strains of rats. However, purine metabolism was proven not to be implicated as an important factor. Subsequently, other factors responsible for the strain diffe...

2006-01-01

34

Feynman graphs and generalized eikonal approach to high energy knock-out processes  

International Nuclear Information System (INIS)

The cross section of hard semiexclusive A(e,e"'N)(A-1) reactions for fixed missing energy and momentum is calculated within the eikonal approximation. Relativistic dynamics and kinematics of high energy processes are unambiguously accounted for by using the analysis of appropriate Feynman diagrams. A significant dependence of the final state interactions on the missing energy is found, which is important for interpretation of forthcoming color transparency experiments. A new, more stringent kinematic restriction on the region where the contribution of short-range nucleon correlations is enhanced in semiexclusive knock-out processes is derived. It is also demonstrated that the use of light-cone variables leads to a considerable simplification of the description of high energy knock-out reactions. copyright 1997 The American Physical Society.

35

/sup 90,91/Zr (n,#alpha#) /sup 87,88/Sr reactions at 14.3 and 18.15 MeV incident neutron energy  

International Nuclear Information System (INIS)

Measurements of alpha spectra in the (n, #alpha#) reactions induced on /sup 90,91/Zr at 14.3 and 18.15 MeV incident neutron energy are presented. A microscopic calculation of these spectra has been made using both pick-up and knock-on theories, and in both cases only one overall normalizing factor, which is the same for the two target nuclei and incident energies and all the considered transitions, appears as a free parameter in the calculation. Pick-up calculations provide a very satisfactory reproduction of the data. Knock-on calculations reproduce many qualitative features of the measured spectra, but do not allow a fully satisfactory reproduction of them. While the results obtained do not exclude knock-on contributions to these reactions, their presence is not established.

36

Quantitative transfer of the molybdenum cofactor from xanthine oxidase and from sulphite oxidase to the deficient enzyme of the nit-1 mutant of Neurospora crassa to yield active nitrate reductase.  

UK PubMed Central (United Kingdom)

An assay method is described for measurement of absolute concentrations of the molybdenum cofactor, based on complementation of the defective nitrate reductase ('apo nitrate reductase') in extracts...Full Text Available

1984-04-15

37

Nature of plant stimulators in the production of Acetobacter xylinum ({open_quotes}Tea fungas{close_quotes}) biofilm used in skin therapy  

Energy Technology Data Exchange (ETDEWEB)

Caffeine and related xanthines were identified as potent stimulators for the bacterial cellulose production in A. xylinum. These compounds are present in several plants whose infusions are useful as culture-medium supplements for this acetobacterium. The proposed target for these native purine-like inhibitory substances is the novel diguanyl nucleotide phosphodiesterase(s) that participates in the bacterial cellulogenic complex.

1991-12-31

38

Effect of gasoline octane quality on vehicle acceleration performance  

Energy Technology Data Exchange (ETDEWEB)

A study was conducted under the auspices of the Coordinating Research Council, Inc. (CRC) to assess the potential effects of gasoline octane quality on vehicle acceleration performance. Twelve participating laboratories, representing both the oil and the automotive industries, tested a total of 182 vehicles as part of the 1989 CRC Octane Number Requirement Survey. The vehicles consisted of 78 with electronic knock control systems and 104 without. All testing was performed using the 1989/1990 CRC FBRU fuel series. The results showed that acceleration performance of vehicles with knock sensors was significantly affected by gasoline octane quality. Octane effects on acceleration performance were most pronounced at maximum-throttle (detent) conditions and at octane levels below the vehicles' octane requirements; however, some knock-sensor vehicles did show improved acceleration performance with fuels at octane levels ...

1991-07-01

39

Performance improvement by control of flow rates and diesel injection timing on dual-fuel engine with ethanol  

Energy Technology Data Exchange (ETDEWEB)

To utilize ethanol from agricultural residue as a fuel in diesel engines, a dual-fuel engine was developed. The engine, which was equipped with a system to electrically control diesel and alcohol flow rates, met basic requirements of a tractor engine, including engine speed control and setting of the torque curve. However, engine knock due to alcohol was a significant drawback. A diesel injection pump with a timing and flow rate control system was adapted, and the effect of injection timing on combustion and performance was investigated. It was observed that the timing control was effective in reducing engine knock caused by rapid alcohol combustion. (author)

1996-04-01

40

Detailed kinetic modeling of autoignition chemistry  

Energy Technology Data Exchange (ETDEWEB)

The development of detailed chemical kinetic reaction mechanisms for analysis of autoignition and knocking of hydrocarbon fuels is described. In particular, kinetic processes of concern for the oxidation of complex hydrocarbon fuel molecules are emphasized. The wide ranges of temperature and pressure which are encountered by end gases in automobile engine combustion chambers result in extreme demands on reaction mechanisms which are intended to describe knocking conditions and predict rates of combustion and ignition. The reactions and chemical species which are most important in each temperature and pressure regime are discussed, and the validation of these reaction mechanisms through comparison with idealized experimental results is described. 53 refs., 8 figs., 5 tabs.

1987-07-22

 
 
 
 
41

The mechanism of thioredoxin reductase from human placenta is similar to the mechanisms of lipoamide dehydrogenase and glutathione reductase and is distinct from the mechanism of thioredoxin reductase from Escherichia?coli  

UK PubMed Central (United Kingdom)

Thioredoxin reductase, lipoamide dehydrogenase, and glutathione reductase are members of the pyridine nucleotide–disulfide oxidoreductase family of dimeric flavoenzymes. The mechanisms and structures...Full Text Available

1997-04-15

42

The complete sequence of a full length cDNA for human liver glyceraldehyde-3-phosphate dehydrogenase: evidence for multiple mRNA species.  

UK PubMed Central (United Kingdom)

A recombinant M13 clone (O42) containing a 65 b.p. cDNA fragment from human fetal liver mRNA coding for glyceraldehyde-3-phosphate dehydrogenase has been identified and it has been used to isolate from...Full Text Available

1984-12-11

43

Ribose metabolism and nucleic acid synthesis in normal and glucose-6-phosphate dehydrogenase-deficient human erythrocytes infected with Plasmodium falciparum.  

UK PubMed Central (United Kingdom)

The metabolism of pentose-phosphate was investigated in Plasmodium falciparum-infected normal and glucose-6-phosphate dehydrogenase (G6PD)-deficient human red blood cells in vitro. 5'-Phosphoribosyl-1-pyrophosphate...Full Text Available

1986-04-01

44

D-Glyceraldehyde-3-Phosphate Dehydrogenase: Three-Dimensional Structure and Evolutionary Significance  

UK PubMed Central (United Kingdom)

A 3.0-Å resolution electron density map of lobster glyceraldehyde-3-phosphate dehydrogenase (EC 1.2.1.12) was computed. The essentially single isomorphous replacement map was very substantially...Full Text Available

1973-11-01

45

CRC customer versus rater octane number requirement program (1990)  

Energy Technology Data Exchange (ETDEWEB)

A CRC cooperative program was conducted to determine the difference in octane requirements between technical raters and 'customers' (the general driving public). The tests were conducted in two phases, with the second being a repeat of the first to verify the results obtained. The trained raters used the CRC E-15 procedure to determine the octane requirement of the vehicles while the customers' perception and objection to knock were determined through the use of a questionnaire. The customers' responses (perception and objection level) were based upon audible knock, acceleration performance, and after-run on a series of full-boiling-range customer/rater unleaded (FBRCU) reference-fuels. Data were analyzed from 168 1988-1991 model-year vehicles, with 126 of these tested in Phase II. The results showed that the customers, objections and perceptions were overwhelmingly based on knock, rather ...

1993-10-01

46

Metabolic and molecular stress responses of gilthead seam bream Sparus aurata during exposure to low ambient temperature: an analysis of mechanisms underlying the winter syndrome  

British Library Electronic Table of Contents (United Kingdom)

The winter syndrome in the gilthead sea bream Sparus aurata indicates that the species is exposed to critically low temperatures in Mediterranean aquaculture in winter. The present study of metabolic patterns and molecular stress responses during cold exposure was carried out to investigate this ?disease?, in light of the recent concept of oxygen and capacity limited thermal tolerance. The metabolic profile of fuel oxidation was examined by determining the activities of the enzymes hexokinase (HK), aldolase (Ald), pyruvate kinase (PK), l-lactate dehydrogenase (l-LDH), citrate synthase (CS), malate dehydrogenase (MDH) and 3-hydroxyacyl CoA dehydrogenase (HOAD) in heart, red and white muscle after exposure to temperatures of 10, 14 and 18?C. Especially, the increase in LDH activity combined ...

2010-01-01

47

Identification and characterization of retinoid-active short-chain dehydrogenases/reductases in Drosophila melanogaster  

British Library Electronic Table of Contents (United Kingdom)

Background In chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid metabolism of protostomes, such as Drosophila melanogaster. Methods Drosophila genome was searched for genes encoding proteins with ?50% identity to human retinol dehydrogenase 12 (RDH12). The corresponding proteins were expressed in Sf9 cells and biochemically characterized. Their phylogenetic relationships were analyzed using PHYLIP software. Results A total of six Drosophila SDR genes were identified. Five of these genes are clustered on chromosome 2 and one is located on chromosome X. The deduced proteins are 300 to 406 amino acids long and are associated with microsomal membranes. They recognize all-trans-retinaldehyd...

2009-01-01

48

Use of Dimethyl Suberimidate, a Cross-Linking Reagent, in Studying the Subunit Structure of Oligomeric Proteins*  

UK PubMed Central (United Kingdom)

Amidination of aldolase, glyceraldehyde-3-phosphate dehydrogenase, tryptophan synthetase B protein, L-arabinose isomerase, and the catalytic subunit of E. coli aspartate transcarbamylase...Full Text Available

1970-07-01

49

Pyruvate Dehydrogenase Complex from Germinating Castor Bean Endosperm 1  

UK PubMed Central (United Kingdom)

Subcellular organelles from castor bean (Ricinus communis) endosperm were isolated on discontinuous sucrose gradients from germinating seeds which were 1 to 7 days postimbibition. Marker...Full Text Available

1980-02-01

50

Mycophenolic acid inhibits activation of inducible nitric oxide synthase in rodent fibroblasts  

UK PubMed Central (United Kingdom)

Mycophenolate mofetil (MMF) is an immunosuppressive drug that acts as a selective inhibitor of inosine monophosphate dehydrogenase (IMPDH). MMF has recently been shown to inhibit the enzymatic activity...Full Text Available

2003-05-01

51

Isozymes of the Glycolytic Enzymes in Endosperm from Developing Castor Oil Seeds 1  

UK PubMed Central (United Kingdom)

Ion filtration chromatography on diethylaminoethyl-Sephadex A-25 has been used to separate two isozymes each of triose phosphate isomerase, glyceraldehyde 3-phosphate dehydrogenase, glycerate 3-phosphate...Full Text Available

1982-04-01

52

Isoenzymes of Sugar Phosphate Metabolism in Endosperm of Germinating Castor Beans 1  

UK PubMed Central (United Kingdom)

Two isoenzymes each of phosphoglucomutase, hexose phosphate isomerase, aldolase, fructose diphosphatase, phosphofructokinase, and 6-phosphogluconate dehydrogenase have been separated by DEAE-cellulose...Full Text Available

1981-06-01

53

Identification of a new gene, molR, essential for utilization of molybdate by Escherichia coli.  

UK PubMed Central (United Kingdom)

A mutation in a new gene, molR, prevented the synthesis in Escherichia coli of molybdoenzymes, including the two formate dehydrogenase isoenzymes, nitrate reductase and trimethylamine-N-oxide reductase....Full Text Available

1990-04-01

54

Review of combustion processes in the dual fuel engine: the gas diesel engine  

Energy Technology Data Exchange (ETDEWEB)

This review examines the characteristics of the compression-ignition type of dual-fuel engine and the combustion phenomena that affect these characteristics. The specific areas covered involve normal combustion processes, the nature and origin of engine knock, operation with LNG, and the effect of intake temperature on combustion efficiency and exhaust composition.

1980-01-01

55

Highly efficient gene silencing using perfect complementary artificial miRNA targeting AP1 or heteromeric artificial miRNA targeting AP1 and CAL genes  

UK PubMed Central (United Kingdom)

Gene silencing is a useful technique for elucidating biological function of genes by knocking down their expression. A recently developed artificial microRNAs (amiRNAs) exploits an endogenous...Full Text Available

2009-03-01

56

Alternative fuels in diesel engine  

Energy Technology Data Exchange (ETDEWEB)

In this investigation natural gas has been used as an alternative fuel in diesel engines. Experiments have been performed to study the performance of the dual fuel engine with different diesel quantities as pilot injection. It was suggested in this research that combustion in the dual fuel engine occurred in four stages: the delay period, the slow stage of combustion, the rapid stage of combustion and the fourth stage of combustion. Because of the slower flame speed of natural gas and also because of the prolonged delay period, the combustion of the gas-air continued well into the expansion stroke. These resulted in lower efficiency and higher brake specific fuel consumption, and also higher exhaust gas temperature and higher carbon monoxide in the exhaust when the engine ran on dual fuel. The carbon dioxide and black smoke in the exhaust decreased as the gas was introduced in the engine. The ratio of alternative to diesel fuel was varied at the same load also at different load ...

1991-01-01

57

Performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas  

Energy Technology Data Exchange (ETDEWEB)

This study investigated the engine performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas and ignited by a pilot amount of diesel fuel. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with exhaust gas recirculation (EGR). The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first without EGR condition up to the maximum possible fuel-air equivalence ratio of 0.65. A maximum indicated mean effective pressure (IMEP) of 1425 kPa and a thermal efficiency of 39% were obtained. However, the nitrogen ...

2009-12-15

58

An enzyme-amplified microtiter plate assay for ethanol: Its application to the detection of peanut ethanol and alcohol dehydrogenase  

Energy Technology Data Exchange (ETDEWEB)

A calorimetric microliter plate assay for ethanol amplified by aldehyde dehydrogenase (ALDH) was developed. In the assay ethanol from a sample took part in a chain-reaction catalyzed by alcohol dehydrogenase (ADH) and amplified by ALDH in the presence of NAD{sup +}, diaphorase, and p-ibdonitrotetrazolium-violet (INT-violet)(a precursor of red product). The resultant reaction gave a red color, the intensity of which was proportional to the amount of ethanol present. Using the technique, the content of activity from peanuts of differing maturity and curing stages were determined respectively. Data showed that immature peanuts had a higher level of ethanol and a lower ADH activity than mature peanuts, and that the level of ethanol and ADH activity decreased with the curing time. This indicates that peanut maturity and curing have an effect on ethanol. Also, this implies that other peanut volatiles could be affected in the same way as ethanol, a ...

1995-12-01

59

Helium atom doping of molybdenum and its influence on the radiation hardenings  

International Nuclear Information System (INIS)

Experimental results on study of helium concentration influence on degree of molybdenum radiation hardening for various method of cyclotron doping differing in degree and damage character are presented. It is established that accumulation of helium atoms in molybdenum for simultaneous formation of radiation defects caused by low energetic primary-knocked atoms leads to higher degree of hardening than for high energetic ion irradiation. It is shown that with increase of helium atom concentration the degree of radiation hardening for the same level of damage increases. 4 refs.; 3 figs. (author).

1990-05-22

60

Distribution of 6 q functions in nuclei and quark enhancement of hard processes with deuteron emission  

International Nuclear Information System (INIS)

"2H, "4He, "1"6O, "4"0Ca, "8"0Zr, "1"4"0Yb, "2"2"4112, "3"3"6168 nuclei are invesigated in terms of flucton model. Effective numbers of nuclear fluctons and deuterons are calculated. Values of complete effective numbers of low-radius deuterons and fluctons with S=1 spin and T=0 isospin are presented. Investigation results of inclusive reactions of quasi-elastic knock-out of deuterons by fast protons are discussed. 9 refs.; 1 fig.; 1 tab.

1988-06-14

 
 
 
 
61

Improving the performance of dual fuel engines running on natural gas/LPG by using pilot fuel derived from jojoba seeds  

Energy Technology Data Exchange (ETDEWEB)

The use of jojoba methyl ester as a pilot fuel was investigated for almost the first time as a way to improve the performance of dual fuel engine running on natural gas or liquefied petroleum gas (LPG) at part load. The dual fuel engine used was Ricardo E6 variable compression diesel engine and it used either compressed natural gas (CNG) or LPG as the main fuel and jojoba methyl ester as a pilot fuel. Diesel fuel was used as a reference fuel for the dual fuel engine results. During the experimental tests, the following have been measured: engine efficiency in terms of specific fuel consumption, brake power output, combustion noise in terms of maximum pressure rise rate and maximum pressure, exhaust emissions in terms of carbon monoxide and hydrocarbons, knocking limits in terms of maximum torque at onset of knocking, and cyclic variability data of 100 engine cycles in terms of maximum pressure and its pressure rise rate average and standard ...

2008-06-15

62

An experimental investigation on engine performance and emissions of a supercharged H{sub 2}-diesel dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

This study investigated the engine performance and emissions of a supercharged engine fueled by hydrogen and ignited by a pilot amount of diesel fuel in dual-fuel mode. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with charge dilution. The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first with hydrogen-operation condition up to the maximum possible fuel-air equivalence ratio of 0.3. A maximum IMEP of 908 kPa and a thermal efficiency of about 42% were obtained. Equivalence ratio could not be further increased due to ...

2010-01-15

63

Improving acetic acid production of Acetobacter pasteurianus AC2005 in hawthorn vinegar fermentation by using beer for seed culture  

British Library Electronic Table of Contents (United Kingdom)

Summary Fruit vinegar can be obtained biologically from the fermentation of fruit wine using species of the genera Acetobacter. However, the productivity of vinegar is generally low because of the inhibition by substrate ethanol and product acetic acid. In this research, the yield of acetic acid, as well as the cell growth, in hawthorn vinegar fermentation was enhanced using beer for seed preparation. The higher yield of acetic acid of AC2005 was because of the higher alcohol dehydrogenase and aldehyde dehydrogenase activities caused by using beer for seed preparation. Furthermore, Acetobacter pasteurianus AC2005 showed acid stability during the fed batch fermentation of hawthorn vinegar.

2010-01-01

64

Histone deacetylase inhibitors and transforming growth factor-b induce 15-hydroxyprostaglandin dehydrogenase expression in human lung adenocarcinoma cells  

British Library Electronic Table of Contents (United Kingdom)

Histone deacetylase (HDAC) inhibitors have been actively exploited as potential anticancer agents. To identify gene targets of HDAC inhibitors, we found that HDAC inhibitors such as sodium butyrate, scriptaid, apicidin and oxamflatin induced the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a potential cyclooxygenase-2 (COX-2) antagonist and tumor suppressor, in a time and concentration dependent manner in A549 and H1435 lung adenocarcinoma cells. Detailed analyses indicated that HDAC inhibitors activated the 15-PGDH promoter-luciferase reporter construct in transfected A549 cells. A representative HDAC inhibitor, scriptaid, and its negative structural analog control, nullscript, were further evaluated at the chromatin level. Scriptaid but not nullscript induced a signific...

2006-01-01

65

Engineered ketol-acid reductoisomerase and alcohol dehydrogenase enable anaerobic 2-methylpropan-1-ol production at theoretical yield in Escherichia coli  

British Library Electronic Table of Contents (United Kingdom)

2-methylpropan-1-ol (isobutanol) is a leading candidate biofuel for the replacement or supplementation of current fossil fuels. Recent work has demonstrated glucose to isobutanol conversion through a modified amino acid pathway in a recombinant organism. Although anaerobic conditions are required for an economically competitive process, only aerobic isobutanol production has been feasible due to an imbalance in cofactor utilization. Two of the pathway enzymes, ketol-acid reductoisomerase and alcohol dehydrogenase, require nicotinamide dinucleotide phosphate (NADPH); glycolysis, however, produces only nicotinamide dinucleotide (NADH). Here, we compare two solutions to this imbalance problem: (1) over-expression of pyridine nucleotide transhydrogenase PntAB and (2) construction of an NADH-de...

2011-01-01

66

Effects of thermically-dry sewage sludge and municipal waste compost amendment on microbial biomass, dehydrogenase activity and CO_2 fluxes in a degraded agricultural soil  

International Nuclear Information System (INIS)

Understanding the dynamic of soil C is a key to managing soil organic matter to enhance soil fertility and ecosystem functioning and reduce trace gas emission from soils. Our objective was to determine the influence of thermically-dry sewage sludge (TSL) and municipal waste compost and the application management on soil (mixed or on soil surface) applied at sludge (TSL) and municipal waste compost and the application management on soil (mixed or on soil surface) applied at two rates of 30 t ha"-1 and 60 t ha"-1, on CO_2 fluxes, microbial biomass C (MBC) and dehydrogenase activity (DH), during an incubation study. (Author)

67

Chromosomal localization and structure of the human type II IMP dehydrogenase gene  

Energy Technology Data Exchange (ETDEWEB)

We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.

1994-05-01

68

Aldehyde dehydrogenase (ALDH) 3A1 expression by the human keratocyte and its repair phenotypes  

British Library Electronic Table of Contents (United Kingdom)

Transparency is essential for normal corneal function. Recent studies suggest that corneal cells express high levels of so-called corneal crystallins, such as aldehyde dehydrogenase (ALDH) and transketolase (TKT) that contribute to maintaining cellular transparency. Stromal injury leads to the appearance of repair phenotype keratocytes, the corneal fibroblast and myofibroblast. Previous studies on keratocytes from species such as bovine and rabbit indicate that the transformation from the normal to repair phenotype is accompanied by a loss of corneal crystallin expression, which may be associated with loss of cellular transparency. Here we investigated if a similar loss occurs with human keratocyte repair phenotypes. Human corneal epithelial cells were collected by scraping and keratocytes...

2006-01-01

69

Synergistic Activation of Glucose-6-Phosphate Dehydrogenase and NAD(P)H oxidase by Src kinase Elevates Superoxide in Type 2 Diabetic, Zucker fa/fa, Rat Liver  

UK PubMed Central (United Kingdom)

Glucose metabolism through glycolysis and hexosamine pathway has been shown to be altered in type 2 diabetes. However, its fate through the pentose phosphate pathway (PPP) is currently unclear....Full Text Available

2009-08-01

70

Superoxide production by NAD(P)H oxidase and mitochondria is increased in genetically obese and hyperglycemic rat heart and aorta before the development of cardiac dysfunction. The role of glucose-6-phosphate dehydrogenase-derived NADPH  

UK PubMed Central (United Kingdom)

Increased oxidative stress is a known cause of cardiac dysfunction in animals and patients with diabetes, but the sources of reactive oxygen species [e.g., superoxide anion (O2)]...Full Text Available

2009-07-01

71

Preferential antitumor effect of the Src inhibitor dasatinib associated with a decreased proportion of aldehyde dehydrogenase 1-positive cells in breast cancer cells of the basal B subtype  

UK PubMed Central (United Kingdom)

BackgroundRecent studies have suggested that the Src inhibitor dasatinib preferentially inhibits the growth of breast cancer cells of the basal-like subtype. To clarify this finding...Full Text Available

72

Helicobacter pylori porCDAB and oorDABC Genes Encode Distinct Pyruvate:Flavodoxin and 2-Oxoglutarate:Acceptor Oxidoreductases Which Mediate Electron Transport to NADP  

UK PubMed Central (United Kingdom)

Helicobacter pylori, a major cause of human gastric disease, is a microaerophilic bacterium that contains neither pyruvate nor 2-oxoglutarate dehydrogenase activity. Previous studies...Full Text Available

1998-03-01

73

Expression Levels of Thymidylate Synthase, Thymidylate Phosphorylase and Dihydropyrimidine Dehydrogenase in Head and Neck Squamous Cell Carcinoma: Preliminary Study  

UK PubMed Central (United Kingdom)

IntroductionPharyngo-laryngeal tumors classified as T3-4, N0-3, M0, are conventionally treated by mutilating surgery (total (pharyngo)-laryngectomy). Neo-adjuvant chemotherapy with...Full Text Available

74

Evidence for Redox Cooperativity between c-Type Hemes of MauG which is Likely Coupled to Oxygen Activation during Tryptophan Tryptophylquinone Biosynthesis  

UK PubMed Central (United Kingdom)

MauG is a novel 42 kDa di-heme protein which is required for the biosynthesis of tryptophan tryptophylquinone, the prosthetic group of methylamine dehydrogenase. The visible absorption and resonance...Full Text Available

2006-01-24

75

Evaluation of the rapid diagnostic test SDFK40 (Pf-pLDH/pan-pLDH) for the diagnosis of malaria in a non-endemic setting  

UK PubMed Central (United Kingdom)

BackgroundThe present study evaluated the SD Bioline Malaria Ag 05FK40 (SDFK40), a three-band RDT detecting Plasmodium falciparum-specific parasite lactate dehydrogenase...Full Text Available

76

Cloning and sequencing of a 2,5-dichloro-2,5-cyclohexadiene-1,4-diol dehydrogenase gene involved in the degradation of gamma-hexachlorocyclohexane in Pseudomonas paucimobilis.  

UK PubMed Central (United Kingdom)

In Pseudomonas paucimobilis UT26, gamma-hexachlorocyclohexane (gamma-HCH) is converted to 2,5-dichloro-2,5-cyclohexadiene-1,4-diol (2,5-DDOL), which is then metabolized to 2,5-dichlorohydroquinone....Full Text Available

1994-06-01

77

Differentiation to adipocytes in accompanied by an increase in the amounts of Gi- and Go-proteins in 3T3-L1 cells  

International Nuclear Information System (INIS)

Treatment of cultures of 3T3-L1 cells with methylisobutyl-xanthine and dexamethasone has been shown to result in accumulation of lipid and conversion to the morphology of adipocytes in more than 90% of the cells. The status of the stimulatory (Gs), inhibitory (Gi) and Go-proteins during the course of 3T3-L1 differentiation was examined. The amount of alpha subunit of Gs (#alpha#Gs), assayed by radiolabeling in the presence of cholera toxin and ["3"2P]NAD"+, increased upon differentiation as previously described by others. The amounts of #alpha#Gi and #alpha#Go assayed by radiolabeling in the presence of pertussis toxin and ["3"2P]NAD"+ increased 3-fold upon differentiation. Immunoblots of cell membranes subjected to gel electrophoresis in sodium dodecyl sulfate were probed with two rabbit antisera raised against bovine brain #alpha#Go and with one raised against the#beta#-subunit of the bovine rod-outer-segment G-protein, referred to as transducin. The ...

1986-06-08

78

Thermoluminescence studies in lead doped KCl and KBr crystals  

International Nuclear Information System (INIS)

Lead is known to enter substitutionally in divalent state when doped in alkali halides. When irradiated at room temperature these lead centers (Pb"+"+) act as traps for electrons knocked off from the halogen ions and become Pb"+ and Pb"0 (for large doses of irradiation). These changes could be followed in the optical absorption studies. These lead-doped crystals after X-ray irradiation yield a thermoluminescence output smaller than that observed in 'pure' crystals. However, two new glow peaks are observed in additions to those due to F-centers. In KCl : Pb and Kbr : Pb crystals part of the F-center glow preceds the new glow peaks. The new peaks are attributed to the Pb"+ and Pb"0 centers. The glow peak temperatures and trap depths for these peaks an obtained by total-curve fitting method are reported. (author).

1975-02-12

79

Study of some nuclear reaction interferences in determination of nitrogen content of plant materials by 14-MeV neutron-activation analysis  

Energy Technology Data Exchange (ETDEWEB)

The nitrogen content of 10 medicinal plant species has been determined by fast-neutron activation analysis (FNAA). Correction factors for the effects of the /sup 16/O(p,..cap alpha..)/sup 13/N knock-on proton-induced reaction and the (n,2n) reactions, which produce interfering positron-emitting radionuclides, have also been determined. The total relative interference from the /sup 16/O(p,..cap alpha..)/sup 13/N and (n,2n) reactions of K, Cl, Fe and Br was found to be 5.1 to 32.1% for the plant samples.

1983-05-01

80

On the suitability of alternate fuels for dual fuel engine operation  

Energy Technology Data Exchange (ETDEWEB)

A compression ignition engine was operated on dual fuel principle inducting two commercial fuels and four pure hydrocarbon fuels in turn through intake manifold along with air and injecting diesel fuel to initiate the combustion in the conventional manner. The engine was operated at different loads and at each load the quantity of inducted fuel was increased gradually till knocking set in. The engine performance and exhaust pollutant emissions were recorded at different operating conditions. It was observed that the extent of induction and the effect on the performance depend on the properties of the inducted fuel such as volatility, self ignition temperature and oxidation characteristics. The energy release during the cycle was also observed to shift depending on the properties of inducted fuel. With the dual fuel operation, the thermal efficiency at part loads was observed to be less compared to neat diesel operation. The thermal efficiency reduced with the ...

1980-12-01

 
 
 
 
81

Identification of the binding domain for NADP"+ of human glucose-6-phosphate dehydrogenase by sequence analysis of mutants  

International Nuclear Information System (INIS)

Human erythrocyte glucose-6-phosphate is normally quite stable in the presence of 10 #mu#M NADP"+. Certain glucose-6-phosphate dehydrogenase variants lose virtually all their activity at this concentration of NADP"+ but are reactivated by 200 #mu#M NADP"+. Such variants presumably have a defect in their NADP"+-binding site. The authors analyzed the sequence of cDNA or genomic DNA from seven unrelated patients with hemolytic anemia due to the inheritance of variants that are reactivated by NADP"+. Six patients had substitutions of one of three adjacent amino acids, and the seventh patient had another amino acid substitution 23 residues downstream. These amino acids are highly conserved, all being present in rat and all but one being found also in Drosophila. The anomalous electrophoretic behavior of some of the variants can be explained by their loss of ability to bind NADP"+. The conclude that the region in which these mutations occur defines the binding domain for ...

82

Genetic engineering of group 2 sigma factor SigE widely activates expressions of sugar catabolic genes in Synechocystis species PCC 6803.  

Science.gov (United States)

Metabolic engineering of photosynthetic organisms is required for utilization of light energy and for reducing carbon emissions.Control of transcriptional regulators is a powerful approach for changing cellular dynamics, because a set of genes is concomitantly regulated. Here, we show that overexpression of a group 2 ? factor, SigE, enhances the expressions of sugar catabolic genes in the unicellular cyanobacterium, Synechocystis sp. PCC 6803. Transcriptome analysis revealed that genes for the oxidative pentose phosphate pathway and glycogen catabolism are induced by overproduction of SigE. Immunoblotting showed that protein levels of sugar catabolic enzymes, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glycogen phosphorylase, and isoamylase, are increased. Glycogen levels are reduced in the SigE-overexpressing strain grown under light. Metabolome analysis revealed that metabolite levels of the TCA cycle and ...

2011-07-11

83

Butyrate Induces Expression of 17?-Hydroxysteroid Dehydrogenase Type 1 in HT29 and SW707 Colorectal Cancer Cells  

British Library Electronic Table of Contents (United Kingdom)

Epidemiological studies have revealed that butyrate and 17?-estradiol (E2) may decrease the incidence of colorectal cancer (CRC). In peripheral tissue, E2 can be produced locally by 17?-hydroxysteroid dehydrogenase 1 (HSD17B1) estrone (E1) reduction. Using quantitative real-time polymerase chain reaction and western blotting analysis, we found that sodium butyrate significantly upregulates HSD17B1 long and short transcripts and protein levels in HT29 and SW707 CRC cells. Chromatin immunoprecipitation analysis showed that upregulation of these transcript levels correlated with an increase in binding of Polymerase II to proximal and distal promoters of HSD17B1. Moreover, we observed that upregulation of HSD17B1 protein levels was associated with increased conversion of E1 to E2 in HT29 and S...

2011-01-01

84

Osteocyte death and hip fracture.  

Science.gov (United States)

The viability of osteocytes can be demonstrated in sawn decalcified sections of bone by their lactate dehydrogenase activity. In the cancellous bone of the femoral head, the proportion of lacunae containing viable osteocytes decreased from 88 +/- 7% (mean +/- SD) at 10-29 years to 58 +/- 12% (P Ultimate compressive strength did not correlate with osteocyte viability. In the femoral head there is gradual, age-related reduction in osteocyte viability that can be more pronounced in hip fracture. Osteocyte death may affect bone quality by impairing repair of fatigue damage. PMID:8275364

1993-01-01

85

Fluoride induced changes in protein metabolism in the tissues of freshwater crab Barytelphusa guerini.  

Science.gov (United States)

Exposure of the freshwater field crab Barytelphusa guerini to a sublethal concentration of NaF (30 mg litre(-1)) caused significant alterations in protein metabolism. After an exposure time of 15 days, the crab was found to have a marked depletion of total protein and free amino acid content. A significant elevation in transaminases, Aspartate aminotransferase (AAT) and Alanine aminotransferase (ALAT), and Glutamate dehydrogenase (GDH) activities was reflected in the free amino acid levels of the tissues. PMID:15092215

1990-01-01

86

Performance and emission comparison of a supercharged dual-fuel engine fueled by producer gases with varying hydrogen content  

Energy Technology Data Exchange (ETDEWEB)

This study investigated the effect of hydrogen content in producer gas on the performance and exhaust emissions of a supercharged producer gas-diesel dual-fuel engine. Two types of producer gases were used in this study, one with low hydrogen content (H{sub 2} = 13.7%) and the other with high hydrogen content (H{sub 2} = 20%). The engine was tested for use as a co-generation engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant injection pressure and injection quantity for different fuel-air equivalence ratios and at various injection timings. The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. Two-stage combustion was obtained; this is an indicator of maximum power output conditions and a precursor of knocking ...

2009-09-15

87

Unraveling photosystems. Final technical report  

Energy Technology Data Exchange (ETDEWEB)

This report highlights four main points. (1) A residue substitution in phosphoribulokinase of Synechocystis PCC 6803 renders the mutant light-sensitive. The authors isolated a light-sensitive mutant (BRLS) of the photosynthetic cyanobacterium Synechocystis 6803 that does not survive exposure to bright light; 70% of BRLS cells die upon exposure to light of > 3000 lux for 2 hr. (2) Excitation energy transfer from phycocyanin to chlorophyll in an apcA-defective mutant of Synechocystis sp. PCC 6803. A greenish mutant of the normally bule-green cyanobacterium Synechocystis sp. PC 6803, designated UV6p, was isolated and characterized. UV6p possesses functional photosystems I and II but lacks normal light harvesting phycobilisomes because allophycocyanin is absent and core-specific linker proteins are almost entirely absent. (3) Deletion of the psbG1 gene of the cyanobacterium Synechocystis sp. PCC 6803 leads to the activation of the cryptic psbG2 gene. The genes psbG1 and psbG2 in ...

1997-09-01

88

Wall quench and flammability limit effects on exhaust hydrocarbon emission. Final technical report, Phase 8, March 1, 1983-February 28, 1984  

Energy Technology Data Exchange (ETDEWEB)

This report documents the concluding efforts at the Engineering Sciences Laboratory of TRW on two specific areas of current research activity within the more general context of proposed lean-burn operation of Otto-cycle-type automotive engines. These areas are: (1) achievement of knock-free performance, both under available fuels and current compression ratios and also under higher-octane fuels (e.g., alcohols) and higher-compression-ratio design (for greater thermal efficiency); and (2) identification of counterstrategies for two-wall (crevice-type) quenching of flame propagation, a phenomenon now widely acknowledged to be the major source of unburned-hydrocarbon emissions exhausted from homogeneous-charge cyclinders. There are certainly other highly active areas of research in Otto-cycle engines, such as turbocharging, ignition devices, and valve design, but the two above-cited topics were the topics of this project.

1984-01-01

89

Performance and exhaust emissions in a natural-gas fueled dual-fuel engine; Tennen gas dual fuel kikan no seino oyobi haiki tokusei  

Energy Technology Data Exchange (ETDEWEB)

In order to establish the optimum fueling in a natural gas fueled dual fuel engine, tests were made for some operational parameters and their combination on the engine performances and the exhaust emissions. The results show that the gas oil quantity should be increased and gas oil injection timing should be advanced to suppress unburned hydrocarbon emission at middle and low output range, while the quantity should be reduced and the timing should be retarded to avoid onset of knock at high loads. The unburned hydrocarbon emission and the thermal efficiency are improved at the same load avoiding too lean natural gas premixture by restriction of intake charge air. However the improvement is limited because the ignition and initial combustion of pilot diesel fuel is deteriorated when the cylinder pressure is excessively lowered by throttling. The increase in pilot gas oil amount is effective for low-load operation and the adequate combination of throttle control and ...

2000-07-25

90

Monitoring system assists in dual-fuel engine knock prevention  

Energy Technology Data Exchange (ETDEWEB)

ABB Industrietechnik AG recently has introduced an augmented version of its Cyldeyt cylinder pressure monitoring system aimed at spark-ignited and diesel/gas, dual-fuel engines. In addition to recording and evaluating cylinder pressure as a means of assessing engine condition, the new Cyldet version now evaluates the cylinder pressure signals to provide protection against pre-ignition related damage. When pre-ignition reaches critical levels, the Cyldet computer relays alarm signals in two stages to the overriding engine control system of the power plant. On receiving the first-stage alarm signal, the engine control system is programmed to adjust one or more engine settings to eliminate preignition - a typical adjustment is to lower charge-air temperature, for example. If such measures fail to eliminate pre-ignition, in the case of a dual-fuel engine, a second alarm signal triggers a reduction in engine load or, as last resort, changeover of the engine to 100% diesel fuel charge. This ...

1995-03-01

91

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO_2 films  

International Nuclear Information System (INIS)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...

92

Implantation damage and anomalous diffusion of implanted boron in silicon through SiO[sub 2] films  

Energy Technology Data Exchange (ETDEWEB)

Boron is implanted in crystalline silicon through oxide layers with different thicknesses. The implantation is carried out at various doses and energies of interest in ultra large scale integration (ULSI) application. Rapid thermal annealings (RTA) are used to obtain shallow junctions and electrical activation of the B atoms. However, transient enhanced diffusion induced by implantation damage can be observed. The boron concentration profiles before and after annealing are obtained with secondary ion mass spectrometry (SIMS). It is found that the diffusion transient in the tail region of the boron profile increases with decreasing oxide thickness. Even more, if the implantation damage concerns mostly the oxide, i.e. when the concentration peak is located in this oxide, the oxygen knocked into the silicon substrate could play this way an important role in restricting the boron diffusion, which is good to obtain very shallow junctions. On the other hand, for thinner ...

1993-07-16

93

Hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel  

International Nuclear Information System (INIS)

A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N_2 dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution to the diesel fuel with zero smoke ...

2009-09-20

94

Formation of nanostructures in UO_2 fuel at high burn-ups  

International Nuclear Information System (INIS)

In the present paper it is assumed that above a limiting value of fission fluency (burn-up) a more intensive process of irradiation introduced chemical interaction occurs. A significant part of fission gas product is thus expected to be chemically bounded in the matrix of UO_2 fuel. The fission gas atoms substituting, for example, uranium atoms in the crystallographic lattice can form weak facets. At a certain saturation condition, division of the grains can occur at the weak facets and the increase in fission-gas products release may be expected. The fact that the process of grain division for high burn-ups (70-80 MWd/kgU) forms an extremely fine structure up to the temperature as high as 1100 "oC and simultaneously the observed decreases in fission gas concentration in the fuel supports this concept. The analysis of fission gas concentration change due to the formation of nanostructures in UO_2 fuel at high burn-ups in terms of total surface area change in a function of burn-up and ...

2001-09-23

95

A study on the amount of pilot injection and its effects on rich and lean boundaries of the premixed CNG/air mixture for a CNG/diesel dual-fuel engine  

Energy Technology Data Exchange (ETDEWEB)

A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must be made richer, otherwise THC emissions ...

2003-07-01

96

The disruption of l-carnitine metabolism by aluminum toxicity and oxidative stress promotes dyslipidemia in human astrocytic and hepatic cells  

British Library Electronic Table of Contents (United Kingdom)

l-Carnitine is a critical metabolite indispensable for the metabolism of lipids as it facilitates fatty acid transport into the mitochondrion where b-oxidation occurs. Human astrocytes (CCF-STTG1 cells) and hepatocytes (HepG2 cells) exposed to aluminum (Al) and hydrogen peroxide (H2O2), were characterized with lower levels of l-carnitine, diminished b-oxidation, and increased lipid accumulation compared to the controls. g-Butyrobetainealdehyde dehydrogenase (BADH) and butyrobetaine dioxygenase (BBDOX), two key enzymes mediating the biogenesis of l-carnitine, were sharply reduced during Al and H2O2 challenge. Exposure of the Al and H2O2-treated cells to a-ketoglutarate (KG), led to the recovery of l-carnitine production with the concomitant reduction in ROS levels. It appears that the chann...

2011-01-01

97

Rapamycin (sirolimus) protects against hypoxic damage in primary heart cultures via Na^+/Ca^2^+ exchanger activation  

British Library Electronic Table of Contents (United Kingdom)

Aims: Rapamycin (sirolimus) is an antibiotic that inhibits protein synthesis through mammalian targeting of rapamycin (mTOR) signaling, and is used as an immunosuppressant in the treatment of organ rejection in transplant recipients. Rapamycin confers preconditioning-like protection against ischemic-reperfusion injury in isolated mouse heart cultures. Our aim was to further define the role of rapamycin in intracellular Ca^2^+ homeostasis and to investigate the mechanism by which rapamycin protects cardiomyocytes from hypoxic damage. Main methods: We demonstrate here that rapamycin protects rat heart cultures from hypoxic-reoxygenation (H/R) damage, as revealed by assays of lactate dehydrogenase (LDH) and creatine kinase (CK) leakage to the medium, by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-d...

2011-01-01

98

Proteomic analysis of apoptosis induction in human lung cancer cells by recombinant MVL  

British Library Electronic Table of Contents (United Kingdom)

Lung cancer is still difficult to treat by current chemotherapeutic procedures. We recently found that MVL, an anti-HIV lectin from blue-green algae Microcystis viridis, also has antitumor activity. The objective of this study was to investigate apoptosis-inducing activity of recombinant MVL (R-MVL) and proteomic changes in A549 cells, and to identify the molecular pathways responsible for the anti-cancer action of R-MVL. We found that R-MVL induces A549 cells apoptosis in a dose-dependent manner by using MTT assay, fluorescent microscope (FM) and flow cytometry (FCM), and the IC50 was calculated to be 24.12??g/ml. Subsequently, 7 altered proteins in R-MVL-treated A549 cells were identified, including upregulated aldehyde dehydrogenase 1 and ?-actin, and five downregulated proteins: heat s...

2011-01-01

99

Peroxisomal hydroxypyruvate reductase is not essential for photorespiration in Arabidopsis but its absence causes an increase in the stoichiometry of photorespiratory CO2 release  

British Library Electronic Table of Contents (United Kingdom)

Recycling of carbon by the photorespiratory pathway involves enzymatic steps in the chloroplast, mitochondria, and peroxisomes. Most of these reactions are essential for plants growing under ambient CO2 concentrations. However, some disruptions of photorespiratory metabolism cause subtle phenotypes in plants grown in air. For example, Arabidopsis thaliana lacking both of the peroxisomal malate dehydrogenase genes (pmdh1pmdh2) or hydroxypyruvate reductase (hpr1) are viable in air and have rates of photosynthesis only slightly lower than wild-type plants. To investigate how disruption of the peroxisomal reduction of hydroxypyruvate to glycerate influences photorespiratory carbon metabolism we analyzed leaf gas exchange in A. thaliana plants lacking peroxisomal HPR1 expression. In addition, b...

2011-01-01

100

Mary Lyon and the hypothesis of random X chromosome inactivation  

British Library Electronic Table of Contents (United Kingdom)

The 50th anniversary of Mary Lyon?s 1961 Nature paper, proposing random inactivation in early embryonic life of one of the two X chromosomes in the cells of mammalian females, provides an opportunity to remember and celebrate the work of those involved. While the hypothesis was initially put forward by Lyon based on findings in the mouse, it was founded on earlier studies, notably the work of Susumu Ohno; it was also suggested independently by Beutler and colleagues using experimental evidence from a human X-linked disorder, glucose-6-phosphate dehydrogenase deficiency, and has proved to be of as great importance for human and medical genetics as it has for general mammalian genetics. Alongside the hypothesis itself, previous cytological studies of mouse and human chromosomes, and the obse...

2011-01-01

 
 
 
 
101

Inhibition of Metabolism of Diethylene Glycol Prevents Target Organ Toxicity in Rats  

British Library Electronic Table of Contents (United Kingdom)

Diethylene glycol (DEG) is an industrial chemical, the misuse of which has led to numerous epidemic poisonings worldwide. The mechanism of its toxicity has not been defined as to the precise relationship between the metabolism of DEG and target organ toxicity. The purpose of this study was to investigate the mechanism for the acute toxicity of DEG, and the effect of the alcohol dehydrogenase inhibitor 4-methylpyrazole (fomepizole), by determining the relationship between accumulation of DEG or its metabolites and the resulting kidney and liver toxicity. Rats were treated by oral gavage with water, 2 g/kg DEG (low dose), 10 g/kg DEG (high dose), or 10 g/kg DEG + fomepizole, and blood and urine were collected over 48 h. Rats treated with high-dose DEG had metabolic acidosis, increased BUN an...

2010-01-01

102

Inactivation of Microcystis aeruginosa with Contact Glow Discharge Electrolysis  

British Library Electronic Table of Contents (United Kingdom)

This work investigated the inactivation of Microcystis aeruginosa (MA) with contact glow discharge electrolysis (CGDE). The influences of applied voltage, current and treatment time on the inactivation rate were critically examined. Based on the above results, the optimal conditions were chosen to sufficiently utilize chemically active species and enhance the inactivation of MA. Under the optimal conditions (voltage: 530?V; current: 30?mA; treatment time: 20?min), the inactivation rate of algae was more than 90% within 5?days incubation after inoculating. At the same time, the concentrations of Chlorophyll-a and dehydrogenase decreased, which demonstrated that 20?min CGDE treatment could effectively inhibit the growth of MA and caused deterioration of cell integrity. The present work would...

2011-01-01

103

Impaired mitochondrial energy metabolism and kinetic properties of cytochrome oxidase following acute aluminium phosphide exposure in rat liver  

British Library Electronic Table of Contents (United Kingdom)

The present study was designed with an aim to analyze the effect of acute aluminium phosphide (ALP) exposure (10mg/kg b.wt, intragastrically) on the kinetic characteristics of cytochrome oxidase and energy metabolism in male Wistar rat liver mitochondria. Liver mitochondrial preparations from ALP-treated rats exhibited significant decrease (66%) in the activity of cytochrome oxidase suggesting that there was a decrease in the catalytic efficiency of the active oxidase molecules on ALP treatment. The decreased activity of cytochrome oxidase with altered NADH and succinic dehydrogenase activities might have contributed towards a significant decline in state 3 and state 4 respiration as observed. These alterations in the electron transport chain complexes in turn adversely affected the ATP sy...

2010-01-01

104

Effect of season on contractile and metabolic properties of desert camel muscle (Camelus dromedarius)  

British Library Electronic Table of Contents (United Kingdom)

Thirty fattened one humped desert camels were used to examine the effect of season on contractile and metabolic properties of Longissimus thoracis (LT) muscle. Ten camels were slaughtered according to seasons of the year (winter, summer and autumn). Season significantly influenced muscle chemical composition, ultimate pH (pHu) and color. Activities of metabolic enzymes were higher during autumn season compared to summer and winter for phosphofructokinase (+64% compared to both seasons) and for isocitrate dehydrogenase (+35% and +145% in autumn vs. summer and winter, respectively). Quantification of muscle myosin heavy chain isoforms by SDS-PAGE electrophoresis showed only presence of type I and type IIa MyHC in camel muscle and indicated high proportion in winter for type I and in autumn f...

2012-01-01

105

Comparative biochemistry of betaine biosynthesis and accumulation in diverse dicot families  

Energy Technology Data Exchange (ETDEWEB)

Salt stress elicits betaine accumulation to high levels in species from several diverse dicot families (Chenopodiaceae, Amaranthaceae, Convolvulaceae, Solanaceae, and Asteraceae). FAM-MS studies with deuterated precursors showed that species from all these families synthesize betaine from choline. Enzyme assays and immunotitration data showed that all accumulating species contained betaine aldehyde dehydrogenase (BADH) enzyme activity recognized by antibodies raised against purified BADH isolated from Spinacia oleracea. Immunoblotting indicated that the BADH monomer was in all cases of Mr {approx} 63,000. The similarity of BADH in the different species is consistent with a single evolutionary origin for the betaine pathway. This was supported by the presence in immunoblots of a cross-reacting band at Mr {approx} 63,000 in Magnolia x Soulangiana, a primitive angiosperm.

1989-04-01

106

Changes in Soil Properties and Vegetable Growth in Preparation for Organic Farming in Hawaii  

British Library Electronic Table of Contents (United Kingdom)

Changes in soil properties and vegetable growth were quantified on a low-fertility tropical soil. Four treatments (two composts, urea, and control) were applied to an Oxisol (Rhodic Haplustox, Wahiawa series) in a field on Oahu, Hawaii. Chinese cabbage (Brassica rapa, Chinensis group) and eggplant (Solanum melongena) were grown sequentially as test crops. Soil quality as measured by hot-water-soluble carbon, dehydrogenase activity, and cation exchange capacity (CEC) increased by compost amendments. Total organic carbon or carbon dioxide (CO2) respiration rate did not correlate with the soil amendments. Nitrogen (N) nutrition was the main factor that improved growth and carotenoid content in cabbage. The urea treatment promoted better growth in cabbage, whereas good-quality compost, made of...

2011-01-01

107

Changes in Energy Metabolism and Antioxidant Defense Systems During Seed Germination of the Weed Species Ipomoea triloba L. and the Responses to Allelochemicals  

British Library Electronic Table of Contents (United Kingdom)

The relationships between changes in energy metabolism and the antioxidant defense system in the weed species Ipomoea triloba L. during seed germination and early seedling growth were investigated. The effects of some common allelochemicals on these parameters also were studied. Respiratory activity and the activities of alcohol dehydrogenase, superoxide dismutase, catalase, guaicol peroxidase, ascorbate peroxidase, glutathione reductase, and lipoxygenase were measured. Mitochondrial oxidative phosphorylation resumed shortly after the seed imbibition period, as indicated by considerable KCN-sensitive respiratory activity in embryos of I. triloba. The occurrence of superoxide dismutase, catalase, guaicol peroxidase, and lipoxygenase activities in the embryos, along with significant KCN-inse...

2011-01-01

108

Biochemical alterations induced by Zn and Cd individually or in combination in the serum of Oreochromis niloticus  

British Library Electronic Table of Contents (United Kingdom)

Measurement of serum biochemical parameters in response to metal exposures can be especially useful to help identify target organs of toxicity as well as the general health status of animals. Oreochromis niloticus were exposed to 5.0?mg/L?Zn, 1.0?mg/L?Cd, and 5.0?mg/L?Zn?+?1.0?mg/L?Cd mixture for 7 and 28?days, and alterations in serum enzyme activities and ion levels were measured. Significant changes in all the biochemical parameters were found to be time dependent. Following metal exposure, alkaline phosphatase activity was elevated at both exposure periods. No changes in activities of lactate dehydrogenase and lipase were observed in response to single or combined Zn and Cd exposure at 7?days while they increased at 28?days. Fish exposed to metals showed a decrease in cholinesterase ac...

2010-01-01

109

The effect of phytic acid on the levels of blood glucose and some enzymes of carbohydrate and lipid metabolism.  

Science.gov (United States)

In this study, six groups of rats were fed as follows: Groups 1 and 2 were fed formulated diets supplemented with zinc or without zinc respectively. Groups 3 and 4 were fed formulated diets supplemented with zinc plus phytic acid extracted from sweet potato (Ipomea batatas) or commercial phytic acid respectively. Groups 5 and 6 were fed formulated diets supplemented with phytic acid extract from sweet potato or commercial phytic acid respectively. The animals were fed for three weeks and then sacrificed The activities of key enzymes of carbohydrate and lipid metabolism as well as transaminases in the liver were determined. Blood glucose level was also assessed. Phytic acid extract consumption from sweet potato and commercial phytic acid plus zinc supplement lowered blood glucose levels. There was no significant change in the activity of 6-phosphogluconate dehydrogenase among the groups. Similarly, phytic acid supplementation showed no significant decrease in the ...

2005-03-01

110

Insulin regulation of protein biosynthesis in differentiated 3T3 adipocytes. Regulation of glyceraldehyde-3-phosphate dehydrogenase  

Energy Technology Data Exchange (ETDEWEB)

The effect of insulin on protein biosynthesis was examined in differentiated 3T3-L1 and 3T3-F442A adipocytes. Insulin altered the relative rate of synthesis of specific proteins independent of its ability to hasten conversion of the fibroblast (preadipocyte) phenotype to the adipocyte phenotype. Although more than one pattern of response to insulin was observed, the authors focused on the induction of a Mr 33,000 protein which was identified as the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Exposure of 3T3 adipocytes to insulin throughout differentiation specifically increased GAPDH activity and protein content by 2- to 3-fold as compared to 3T3 adipocytes differentiated in the absence of insulin. These changes in enzyme activity and content could be accounted for by a 4-fold increase in the relative rate of synthesis of GAPDH and a 9-fold increase in hybridizable mRNA levels. Within 2 h of insulin addition to 3T3 adipocytes differentiated ...

1985-10-05

111

In vitro toxicity of silica nanoparticles in human lung cancer cells  

International Nuclear Information System (INIS)

The cytotoxicity of 15-nm and 46-nm silica nanoparticles was investigated by using crystalline silica (Min-U-Sil 5) as a positive control in cultured human bronchoalveolar carcinoma-derived cells. Exposure to 15-nm or 46-nm SiO_2 nanoparticles for 48 h at dosage levels between 10 and 100 #mu#g/ml decreased cell viability in a dose-dependent manner. Both SiO_2 nanoparticles were more cytotoxic than Min-U-Sil 5; however, the cytotoxicities of 15-nm and 46-nm silica nanoparticles were not significantly different. The 15-nm SiO_2 nanoparticles were used to determine time-dependent cytotoxicity and oxidative stress responses. Cell viability decreased significantly as a function of both nanoparticle dosage (10-100 #mu#g/ml) and exposure time (24 h, 48 h, and 72 h). Indicators of oxidative stress and cytotoxicity, including total reactive oxygen species (ROS), glutathione, malondialdehyde, and lactate dehydrogenase, were quantitatively assessed. Exposure to SiO_2 ...

2006-12-15

112

Increased heterozygosity at the Mdh-B locus in fish inhabiting a rapidly fluctuating thermal environment  

Science.gov (United States)

Populations of a common forage fish, red shiner Notropis lutrensis, were sampled from four localities on the Brazos River, Texas, affected by cold-water discharge from a hydroelectric dam and from unaltered sites in the same region. Polymorphism at the Mdh-B locus, encoding supernatant malate dehydrogenase, indicates that populations within 57 km of the dam are distinctive from other regional populations and possess a unique Mdh-B allele, have significantly higher levels of heterozygosity at the Mdh-B locus, represent a homogeneous set that have significantly different Mdh-B zygotic frequencies from other regional populations, and have significantly different Mdh-B zygotic proportions than would be expected under a Hardy-Weinberg equilibrium. Increased levels of heterozygosity in fish within 57 km of the dam were correlated with discharge-associated fluctuations in water temperature at sampling stations.

1981-05-01

113

Increased ethanol resistance in Ethanolic Escherichia coli by Insertion of heat-shock genes BEM1 and SOD2 from Saccharomyces cerevisiae  

British Library Electronic Table of Contents (United Kingdom)

Ethanol is generally toxic to microorganisms, and intracellular and extracellular accumulation of ethanol inhibits cell growth and metabolism. In this study, pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adhB) were cloned into pET-32a vector and then introduced into E. coli BL21 to produce ethanol. Heat shock genes (BEM1 and SOD2) from Saccharomyces cerevisiae were inserted into recombinant ethanolic E. coli using pET28_a vector to improve ethanol shock resistance. Three different strains were constructed: Ethanolic E. coli (adhB and pdc genes inserted using pET32_a vector), BEM1 gene-inserted E. coli (BEM1 inserted using pET_28a), and SOD2-inserted E. coli (SOD2 inserted using pET28_a). Construction of these three different strains allowed comparison of the functions of these he...

2010-01-01

114

In vivo effects of cadmium chloride on certain aspects of protein metabolism in tissues of a freshwater field crab Barytelphusa guerini  

Energy Technology Data Exchange (ETDEWEB)

Heavy metals discharged from industries are a major source of pollution which has become a threat to all forms of life. Among the various heavy metals, cadmium is known to be highly toxic even in low concentrations. The harmful effects of cadmium is attributed to its effects on sulfhydryl groups of enzymes, especially dehydrogenases. Various aspects of cadmium pollution on fishes have been extensively reviewed. A survey of the literature reveals that few attempts have been made to study the various aspects of cadmium toxicity in crustaceans and these studies were mainly devoted to marine forms. The freshwater crustaceans, particularly the freshwater field crab, Barytelphusa guerini, has received little attention. The present study reports the influence of cadmium on certain aspects of protein metabolism in the tissues of a freshwater field crab, Barytelphusa guerini, and important component of the paddy field ecosystem, exposed to sublethal concentrations of ...

1991-04-01

115

Homo-d-lactic acid production from mixed sugars using xylose-assimilating operon-integrated Lactobacillus plantarum  

British Library Electronic Table of Contents (United Kingdom)

In order to achieve efficient d-lactic acid fermentation from a mixture of xylose and glucose, the xylose-assimilating xylAB operon from Lactobacillus pentosus (PXylAB) was introduced into an l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum (?ldhL1-xpk1::tkt-?xpk2) strain in which the phosphoketolase 1 gene (xpk1) was replaced with the transketolase gene (tkt) from Lactococcus lactis, and the phosphoketolase 2 (xpk2) gene was deleted. Two copies of xylAB introduced into the genome significantly improved the xylose fermentation ability, raising it to the same level as that of ?ldhL1-xpk1::tkt-?xpk2 harboring a xylAB operon-expressing plasmid. Using the two-copy xylAB integrated strain, successful homo-d-lactic acid production was achieved from a mixture of 25?g/l xylos...

2011-01-01

116

Reactive biomolecular divergence in genetically altered yeast cells and isolated mitochondria as measured by biocavity laser spectroscopy : a rapid diagnostic method for studying cellular responses to stress and disease.  

Energy Technology Data Exchange (ETDEWEB)

We report an analysis of four strains of baker's yeast (Saccharomyces cerevisiae) using biocavity laser spectroscopy. The four strains are grouped in two pairs (wild type and altered), in which one strain differs genetically at a single locus, affecting mitochondrial function. In one pair, the wild-type rho+ and a rho0 strain differ by complete removal of mitochondrial DNA (mtDNA). In the second pair, the wild-type rho+ and a rho- strain differ by knock-out of the nuclear gene encoding Cox4, an essential subunit of cytochrome c oxidase. The biocavity laser is used to measure the biophysical optic parameter Deltalambda, a laser wavelength shift relating to the optical density of cell or mitochondria that uniquely reflects its size and biomolecular composition. As such, Deltalambda is a powerful parameter that rapidly interrogates the biomolecular state of single cells and mitochondria. Wild-type cells and mitochondria produce Gaussian-like distributions ...

2006-12-01

117

Performance of spark ignited gas engine and dual fuel engine, and their application  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a practical knowledge on gas engine performance and combustion characteristics which are required by experimental studies for two types of developed gas burning engines, i. e. a spark ignited gas engine and a dual fuel engine, and also introduces their practical use and application. As for dual fuel engine performance, a manifold air pressure of about 27% was decreased, a scavenging ratio of 23% reduced and an exhaust temperature at the turbine inlet on 14% was increased at the gas engine operation under the mean effective cylinder pressure of 1.22 MPa in comparison with the diesel operation. Furthemore, empirical data on the effect of excess air ration on the engine performance and combustion characteristics, a risk of knocking during changing over on the dual fuel engine operation, and the rated output in case of using alternate fuel gas were reported. Two spark ignited gas engines with a rated output of 250 PS each using town gas for the ...

1988-12-01

118

Detailed Chemical Kinetic Reaction Mechanisms for Autoignition of Isomers of Heptane Under Rapid Compression  

Energy Technology Data Exchange (ETDEWEB)

Detailed chemical kinetic reaction mechanisms are developed for combustion of all nine isomers of heptane (C{sub 7}H{sub 16}), and these mechanisms are tested by simulating autoignition of each isomer under rapid compression machine conditions. The reaction mechanisms focus on the manner in which the molecular structure of each isomer determines the rates and product distributions of possible classes of reactions. The reaction pathways emphasize the importance of alkylperoxy radical isomerizations and addition reactions of molecular oxygen to alkyl and hydroperoxyalkyl radicals. A new reaction group has been added to past models, in which hydroperoxyalkyl radicals that originated with abstraction of an H atom from a tertiary site in the parent heptane molecule are assigned new reaction sequences involving additional internal H atom abstractions not previously allowed. This process accelerates autoignition in fuels with tertiary C-H bonds in the parent fuel. In addition, the rates of ...

2001-12-17

119

Deficiency of the housekeeping gene hypoxanthine-guanine phosphoribosyltransferase (HPRT) dysregulates neurogenesis.  

Science.gov (United States)

Neuronal transcription factors play vital roles in the specification and development of neurons, including dopaminergic (DA) neurons. Mutations in the gene encoding the purine biosynthetic enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) cause the resulting intractable and largely untreatable neurological impairment of Lesch-Nyhan disease (LND). The disorder is associated with a defect in basal ganglia DA pathways. The mechanisms connecting the purine metabolic defect and the central nervous system (CNS) phenotype are poorly understood but have been presumed to reflect a developmental defect of DA neurons. We have examined the effect of HPRT deficiency on the differentiation of neurons in the well-established human (NT2) embryonic carcinoma neurogenesis model. We have used a retrovirus expressing a small hairpin RNA (shRNA) to knock down HPRT gene expression and have examined the expression of a number of transcription factors essential for neuronal ...

2009-08-11

120

Cycle-by-cycle variations in spark ignition engine combustion. Part 1: Flame speed and combustion measurements and a simplified turbulent combustion model  

Energy Technology Data Exchange (ETDEWEB)

A phenomenological model of turbulent combustion has been developed and validated against data from wide ranging tests on a Ricardo E6 engine. Most tests used iso-octane, with a range of air fuel ratios and ignition timings, for tests at full throttle (with and without knock) and at part throttle. Some full throttle tests were also conducted with methanol and toluene. The engine performance was characterized by mean and coefficient of variation (CoV) of: the peak pressure, the maximum rate of pressure rise, the IMEP, the burn rate and flame speed measurements. The results have been used to argue that the cycle-by-cycle variations in combustion should be characterized by the CoV of IMEP in preference to the CoV of the maximum cylinder pressure. Evidence is also presented to support the observation that the cycle-by-cycle variations in combustion are lower when the early combustion is more rapid. It has also been shown that the CoV of IMEP is a minimum in the region ...

1996-09-01

 
 
 
 
121

Effects of Multi-ion Irradiation on Microstructural Changes in Lithium Titanate  

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: Li{sub 2}TiO{sub 3} is regarded as one of the most suitable candidates for the solid tritium breeder material of D-T fusion reactors. It is known that, in an operating fusion reactor, the radiation damage in Li{sub 2}TiO{sub 3} will be caused by fast neutrons, energetic tritons and helium ions generated in {sup 6}Li(n,{alpha}){sup 3}H reaction. The irradiation damage caused by such radiation may result in the microstructural changes, and the changes may affect the characteristics of Li{sub 2}TiO{sub 3} such as tritium release behavior. Thus the study of irradiation defects and microstructural changes caused by irradiation in Li{sub 2}TiO{sub 3} is essential to evaluate its irradiation performance. Simulation of the fusion reactor environment and hence the study of a synergistic effect of atomic displacement damage in Li{sub 2}TiO{sub 3} are approached by a simultaneous irradiation with 'triple' ion beams which consist of O{sup 2+}, ...

2007-07-01

122

The Protective Effect of Antioxidants on Oxidative Stress in Rats Exposed to the 950 MHz Electromagnetic Field  

International Nuclear Information System (INIS)

Studies have linked cell phone radiation to health problems such as headaches, high blood pressure, cancer and more. There is a latency period for most diseases and it may take years and more studies before the required weight of evidence is established. But the effects are cumulative and precautions should be taken now before it is too late. The aim of the present study was to investigate if supplementation with antioxidants would protect heart and liver tissues from harmful radiation emitted by cell phone. Thirty two male albino rats were randomly divided into four equal groups: I- Control, II- Antioxidants treated group, III- 950 MHz EMR, IV- 950 MHz EMR + antioxidants. A 950 MHz EMR radiation (217-Hz pulse rate, 2-W maximum peak power, SAR Specific Absorption Rate"1.6 W/Kg) was applied to groups III and IV 60 min/day, for 30 days using an experimental exposure device. Antioxidants supplement (Vitamins A, E and C + Se) was administered to rats daily, by gavages, during the period of ...

123

Tests for the diagnosis of Clostridium difficile infection: the next generation.  

Science.gov (United States)

Clostridium difficile (C. difficile) causes 25-30% of cases of antibiotic associated diarrhea and most cases of pseudomembranous colitis. Patients presenting with diarrhea after hospitalization for 3 or more days should be tested for C. difficile. There are many options available for testing, each of which has inherent advantages and disadvantages. Most laboratories perform toxin testing using an enzyme immunoassay method. In general these tests have sensitivities ranging from 60 to 70% and specificities of 98%. When using these methods, symptomatic patients with negative tests should be tested by another more sensitive method. Until recently, cell culture cytotoxicity neutralization assays (CCNAs) were considered the gold standard in the U.S. A two-step algorithm using an EIA for glutamate dehydrogenase detection followed by testing positives using CCNA, offered an improved alternative until the availability of molecular assays. Although early studies that ...

2011-03-03

124

Structures of trihydroxynaphthalene reductase-fungicide complexes: implications for structure-based design and catalysis  

Energy Technology Data Exchange (ETDEWEB)

Trihydroxynaphthalene reductase catalyzes two intermediate steps in the fungal melanin biosynthetic pathway. The enzyme, a typical short-chain dehydrogenase, is the biochemical target of three commercial fungicides. The fungicides bind preferentially to the NADPH form of the enzyme. Three X-ray structures of the Magnaporthe grisea enzyme complexed with NADPH and two commercial and one experimental fungicide were determined at 1.7 {angstrom} (pyroquilon), 2.0 {angstrom} (2,3-dihydro-4-nitro-1H-inden-1-one, 1), and 2.1 {angstrom} (phthalide) resolutions. The chemically distinct inhibitors occupy similar space within the enzyme's active site. The three inhibitors share hydrogen bonds with the side chain hydroxyls of Ser-164 and Tyr-178 via a carbonyl oxygen (pyroquilon and 1) or via a carbonyl oxygen and a ring oxygen (phthalide). Active site residues occupy similar positions among the three structures. A buried water molecule that is hydrogen bonded to the ...

2010-03-08

125

Sida rhomboidea. Roxb Leaf Extract Down-Regulates Expression of PPAR?2 and Leptin Genes in High Fat Diet Fed C57BL/6J Mice and Retards in Vitro 3T3L1 Pre-Adipocyte Differentiation.  

Science.gov (United States)

Sida rhomboidea. Roxb leaf extract (SRLE) is being used by the populace of North-East India to alleviate symptoms of diabetes and obesity. We have previously reported its hypolipidemic and anti-diabetic properties. In this study, we report the effect of SRLE on (i) in vivo modulation of genes controlling high fat diet (HFD) induced obesity and (ii) in vitro 3T3L1 pre-adipocyte differentiation and leptin release. Supplementation with SRLE significantly prevented HFD induced increment in bodyweight, plasma lipids and leptin, visceral adiposity and adipocyte hypertrophy. Also, SRLE supplementation reduced food intake, down regulated PPAR?2, SREBP1c, FAS and LEP expressions and up-regulated CPT-1 in epididymal adipose tissue compared to obese mice. In vitro adipogenesis of 3T3L1 pre-adipocytes was significantly retarded in the presence of SRLE extract. Also decreased triglyceride accumulation, leptin release and glyceraldehyde-3-Phosphate dehydrogenase activity along ...

2011-07-19

126

Pyridoxine dependent epilepsy and antiquitin deficiency Clinical and molecular characteristics and recommendations for diagnosis, treatment and follow-up.  

Science.gov (United States)

Antiquitin (ATQ) deficiency is the main cause of pyridoxine dependent epilepsy characterized by early onset epileptic encephalopathy responsive to large dosages of pyridoxine. Despite seizure control most patients have intellectual disability. Folinic acid responsive seizures (FARS) are genetically identical to ATQ deficiency. ATQ functions as an aldehyde dehydrogenase (ALDH7A1) in the lysine degradation pathway. Its deficiency results in accumulation of ?-aminoadipic semialdehyde (AASA), piperideine-6-carboxylate (P6C) and pipecolic acid, which serve as diagnostic markers in urine, plasma, and CSF. To interrupt seizures a dose of 100mg of pyridoxine-HCl is given intravenously, or orally/enterally with 30mg/kg/day. First administration may result in respiratory arrest in responders, and thus treatment should be performed with support of respiratory management. To make sure that late and masked response is not missed, treatment with oral/enteral pyridoxine should be ...

2011-05-24

127

Punica granatum peel extract protects against ionizing radiation-induced enteritis and leukocyte apoptosis in rats  

International Nuclear Information System (INIS)

Radiation-induced enteritis is a well-recognized sequel of therapeutic irradiation. Therefore we examined the radioprotective properties of Punica granatum peel extract (PPE) on the oxidative damage in the ileum. Rats were exposed to a single whole-body X-ray irradiation of 800 cGy. Irradiated rats were pretreated orally with saline or PPE (50 mg/kg/day) for 10 days before irradiation and the following 10 days, while control rats received saline or PPE but no irradiation. Then plasma and ileum samples were obtained. Irradiation caused a decrease in glutathione and total antioxidant capacity, which was accompanied by increases in malondialdehyde levels, myeloperoxidase activity, collagen content of the tissue with a concomitant increase 8-hydroxy-2'-deoxyguanosine (an index of oxidative DNA damage). Similarly, pro-inflammatory cytokines (TNF-?, IL-1? and IL-6) and lactate dehydrogenase were elevated in irradiated groups as compared to control. PPE treatment reversed ...

2009-07-01

128

Measurement of 12(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid and its metabolite 12-oxo-5Z,8E,10E-heptadecatrienoic acid in human plasma by gas chromatography/negative ion chemical ionization mass spectrometry  

International Nuclear Information System (INIS)

Thromboxane A2, the predominant product of arachidonic acid metabolism in the blood platelet, is a potent vasoconstrictor and platelet agonist. During its biosynthesis from cyclic endoperoxide, 12(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) is formed in equal amounts. The further metabolism of HHT, catalyzed by 15-hydroxyprostaglandin dehydrogenase, leads to 12-oxo-5Z,8E,10E-heptadecatrienoic acid (Oxo-HT). Sample workup procedures are described which allow for the sensitive and reproducible determination of these two arachidonic acid metabolites in human plasma by gas chromatography-mass spectrometry in the presence of deuterated analogues as internal standards. HHT is derivatized to the pentafluorobenzyl ester tert-butyldimethylsilyl ether. In order to enable quantification of low concentrations of about 10 pg/ml in nonstimulated human plasma, the samples have to be purified by HPLC. Oxo-HT is derivatized to the pentafluorobenzyl ester, which is purified by ...

1990-01-01

129

Inhibitory effect of transforming growth factor-. beta. (TGF-. beta. ) on insulin-like growth factor 1 (IGF-1)-induced proliferation and differentiation in primary cultures of pig preadipocytes  

Energy Technology Data Exchange (ETDEWEB)

The influence of serum, IGF-1 and TGF-{beta} on the differentiation of preadipocytes was examined in primary cultures of porcine adipose tissue cells. In serum-supplemented or serum-free, IGF-1 (1 and 10 nM) had no effect on total cell number. However, IGF-1 (10nM) increased adipocyte number only in serum-supplemented (1% pig serum) cultures, whereas TGF-{beta} (15 pm) reduced the adipocyte number in the presence and absence of IGF-1. Replication of preadipocytes was analyzed with a ({sup 3}H) thymidine assay. Preadipocyte proliferation (cpm in adipocyte fraction) was increased by IGF-1 (10nM) only in cultures containing pig serum. TGF-{beta} had no effect on preadipocyte proliferation specifically, but slightly increased total ({sup 3}H) thymidine incorporation in cultures with serum. Glycerol phosphate dehydrogenase (GPDH) specific activity was decreased by adding TGF-{beta} to serum-free cultures but TGF-{beta} had little effect in serum-supplemented cultures. ...

1990-02-26

130

Inhibitory effect of transforming growth factor-#beta# (TGF-#beta#) on insulin-like growth factor 1 (IGF-1)-induced proliferation and differentiation in primary cultures of pig preadipocytes  

International Nuclear Information System (INIS)

The influence of serum, IGF-1 and TGF-#beta# on the differentiation of preadipocytes was examined in primary cultures of porcine adipose tissue cells. In serum-supplemented or serum-free, IGF-1 (1 and 10 nM) had no effect on total cell number. However, IGF-1 (10nM) increased adipocyte number only in serum-supplemented (1% pig serum) cultures, whereas TGF-#beta# (15 pm) reduced the adipocyte number in the presence and absence of IGF-1. Replication of preadipocytes was analyzed with a ["3H] thymidine assay. Preadipocyte proliferation (cpm in adipocyte fraction) was increased by IGF-1 (10nM) only in cultures containing pig serum. TGF-#beta# had no effect on preadipocyte proliferation specifically, but slightly increased total ["3H] thymidine incorporation in cultures with serum. Glycerol phosphate dehydrogenase (GPDH) specific activity was decreased by adding TGF-#beta# to serum-free cultures but TGF-#beta# had little effect in serum-supplemented cultures. Cellular ...

1991-04-21

131

High extracellular calcium attenuates adipogenesis in 3T3-L1 preadipocytes  

International Nuclear Information System (INIS)

We studied the effect of extracellular Ca"2"+ concentration ([Ca"2"+]_e) on adipocyte differentiation. Preadipocytes exposed to continuous [Ca"2"+]_e higher than 2.5 mmol/l accumulated little or no cytoplasmic lipid compared to controls in 1.8 mmol/l [Ca"2"+]_e. Differentiation was monitored by Oil Red O staining of cytoplasmic lipid and triglyceride assay of accumulated lipid, by RT-PCR analysis of adipogenic markers, and by the activity of glycerol-3-phosphate dehydrogenase (GPDH). Elevated [Ca"2"+]_e inhibited expression of peroxisome proliferator-activated receptor #gamma#, CCAAT/enhancer binding protein #alpha#, and steroid regulatory binding element protein. High [Ca"2"+]_e significantly inhibited differentiation marker expression including adipocyte fatty acid binding protein, and GPDH. The decrease in Pref-1 expression that accompanied differentiation also was prevented by high [Ca"2"+]_e. Treatment of 3T3-L1 cells with high [Ca"2"+]_e did not significantly ...

2004-12-10

132

Effects of ischemic-like insult on myocardial /sup 201/Tl accumulation  

Energy Technology Data Exchange (ETDEWEB)

Despite extensive clinical use of thallium-201 (/sup 201/Tl) for myocardial imaging, the effect of ischemia on myocardial accumulation and release of /sup 201/Tl independent of flow has not been fully defined. Therefore, myocardial accumulation of /sup 201/Tl in response to ischemic-like myocardial injury was assessed in vitro using the cultured fetal mouse heart preparation. Cultured fetal mouse hearts (n . 311) were subjected to injury simulating ischemia by deprivation of oxygen and oxidizable substrates for periods ranging from 15 minutes to 10 hours. The extent of irreversible injury was determined by the percentage of lactic dehydrogenase (LDH) lost from the hearts to the culture medium during recovery from injury. Injury was essentially reversible at 1 hour of insult. The fraction of /sup 201/Tl content in injured compared with control hearts was not significantly lower after 1 hour of insult. By 3 hours of insult, irreversible injury as assessed by loss of ...

1983-04-01

133

Effects of chronic swimming training on cardiac sarcolemmal function and composition.  

Science.gov (United States)

Cardiac contractile function is dependent on the integrity and function of the sarcolemmal membrane. Swimming exercise training is known to increase cardiac contractile performance. The purpose of the present study was to examine whether a swimming exercise program would alter sarcolemmal enzyme activity, ion flux, and composition in rat hearts. After approximately 11 wk of exercise training, cardiac myosin and actomyosin Ca2+-adenosinetriphosphatase (ATPase) activity was significantly higher in exercised rat hearts than in sedentary control rat hearts. Glycogen content was increased in plantaris and gastrocnemius muscles from exercised animals as was succinic dehydrogenase activity in gastrocnemius muscle of exercised rats in comparison to sedentary rat preparations. Sarcolemmal vesicles were isolated from hearts of exercise-trained and control rats. Sarcolemmal Na+-K+-ATPase and K+-p-nitrophenylphosphatase activities, Na+-Ca2+ exchange, and passive Ca2+ binding ...

1989-04-01

134

Cloning of Drosophila transcription factor Adf-1 reveals homology to Myb oncoproteins.  

Science.gov (United States)

The Drosophila sequence-specific DNA binding protein, Adf-1, is capable of activating transcription of the alcohol dehydrogenase gene, Adh, and is implicated in the transcriptional control of other developmentally regulated genes. We have cloned the cDNA encoding Adf-1 by generating specific DNA probes deduced from partial amino acid sequence of the protein. Several cDNA clones encoding an extended open reading frame were isolated from a phage lambda library. The complete amino acid sequence of Adf-1 deduced from the longest cDNA reveals structural similarities to the putative helix-turn-helix DNA binding motif of Myb and Myb-related proteins. DNA sequence analysis of genomic clones and Northern blot analysis of mRNA suggest that Adf-1 is a single-copy gene encoding a 1.9-kb transcript. Purified recombinant Adf-1 expressed in Escherichia coli binds specifically to Adf-1 recognition sites and activates transcription of a synthetic Adh promoter in vitro in a manner ...

1992-01-15

135

Characterization of the major phosphoprotein and its kinase on the surface of the rat adipocyte  

Energy Technology Data Exchange (ETDEWEB)

Intact rat fat cell exposed to 12.5 ..mu..M (..gamma..-32P)ATP incorporate label into specific proteins within minutes. By solubilizing the reaction mixture with SDS which bypasses the subcellular fractionation steps, the labeled proteins can be identified in autoradiographs of SDS-PAGE gels. The most prominently labeled protein has an M/sub r/ of 42,000. Localization of this component to the cell surface can be made on the basis of inhibition of phosphorylation by addition of a protein derived from the rat brain with protein kinase inhibitory property, susceptibility of the phosphorylated protein to the tryptic digestion, inhibition of phosphorylation of this protein after brief exposure to melittin. To rule out the possibility that the cell surface protein might be a mitochondrial contaminant from broken cells, /sup 32/Pi-labeled and (..gamma..-/sup 32/P)ATP-labeled cells were chromatographed on a rabbit anti-pyruvate dehydrogenase antibody-Sepharose 4B column. A ...

1986-12-01

136

Biosynthesis of sucrose and mannitol as a function of leaf age in celery (Apium graveolens L. )  

Energy Technology Data Exchange (ETDEWEB)

In celery (Apium graveolens L.), the two major translocated carbohydrates are sucrose and the acyclic polyol mannitol. Their metabolism, however, is different and their specific functions are uncertain. To compare their roles in carbon partitioning and sink-source transitions, developmental changes in /sup 14/CO/sub 2/ labeling, pool sizes, and key enzyme activities in leaf tissues were examined. The proportion of label in mannitol increased dramatically with leaf maturation whereas that in sucrose remained fairly constant. Mannitol content, however, was high in all leaves and sucrose content increased as leaves developed. Activities of mannose-6-P reductase, cytoplasmic and chloroplastic fructose-1,6-bis-phosphatases, sucrose phosphate synthase, and sucrose synthase increased with leaf maturation and decreased as leaves senesced. Ribulose bisphosphate carboxylase and nonreversible glyceraldehyde-3-P dehydrogenase activities rose as leaves developed but did not ...

1988-01-01