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Sample records for alanine aminotransferase ratio

  1. Alanine aminotransferase controls seed dormancy in barley

    Science.gov (United States)

    Sato, Kazuhiro; Yamane, Miki; Yamaji, Nami; Kanamori, Hiroyuki; Tagiri, Akemi; Schwerdt, Julian G.; Fincher, Geoffrey B.; Matsumoto, Takashi; Takeda, Kazuyoshi; Komatsuda, Takao

    2016-01-01

    Dormancy allows wild barley grains to survive dry summers in the Near East. After domestication, barley was selected for shorter dormancy periods. Here we isolate the major seed dormancy gene qsd1 from wild barley, which encodes an alanine aminotransferase (AlaAT). The seed dormancy gene is expressed specifically in the embryo. The AlaAT isoenzymes encoded by the long and short dormancy alleles differ in a single amino acid residue. The reduced dormancy allele Qsd1 evolved from barleys that were first domesticated in the southern Levant and had the long dormancy qsd1 allele that can be traced back to wild barleys. The reduced dormancy mutation likely contributed to the enhanced performance of barley in industrial applications such as beer and whisky production, which involve controlled germination. In contrast, the long dormancy allele might be used to control pre-harvest sprouting in higher rainfall areas to enhance global adaptation of barley. PMID:27188711

  2. Alanine aminotransferase controls seed dormancy in barley.

    Science.gov (United States)

    Sato, Kazuhiro; Yamane, Miki; Yamaji, Nami; Kanamori, Hiroyuki; Tagiri, Akemi; Schwerdt, Julian G; Fincher, Geoffrey B; Matsumoto, Takashi; Takeda, Kazuyoshi; Komatsuda, Takao

    2016-01-01

    Dormancy allows wild barley grains to survive dry summers in the Near East. After domestication, barley was selected for shorter dormancy periods. Here we isolate the major seed dormancy gene qsd1 from wild barley, which encodes an alanine aminotransferase (AlaAT). The seed dormancy gene is expressed specifically in the embryo. The AlaAT isoenzymes encoded by the long and short dormancy alleles differ in a single amino acid residue. The reduced dormancy allele Qsd1 evolved from barleys that were first domesticated in the southern Levant and had the long dormancy qsd1 allele that can be traced back to wild barleys. The reduced dormancy mutation likely contributed to the enhanced performance of barley in industrial applications such as beer and whisky production, which involve controlled germination. In contrast, the long dormancy allele might be used to control pre-harvest sprouting in higher rainfall areas to enhance global adaptation of barley. PMID:27188711

  3. Higher Ratio of Serum Alpha-Fetoprotein Could Predict Outcomes in Patients with Hepatitis B Virus-Associated Hepatocellular Carcinoma and Normal Alanine Aminotransferase.

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    Young-Il Kim

    Full Text Available The role of serum alpha-fetoprotein (AFP levels in the surveillance and diagnosis of hepatocellular carcinoma (HCC is controversial. The aim of this study was to investigate the value of serially measured serum AFP levels in HCC progression or recurrence after initial treatment.A total of 722 consecutive patients newly diagnosed with HCC and treated at the National Cancer Center, Korea, between January 2004 and December 2009 were enrolled. The AFP ratios between 4-8 weeks post-treatment and those at the time of HCC progression or recurrence were obtained. Multivariate logistic regression analysis was performed to correlate the post-treatment AFP ratios with the presence of HCC progression or recurrence.The etiology of HCC was related to chronic hepatitis B virus (HBV infection in 562 patients (77.8%, chronic hepatitis C virus (HCV infection in 74 (10.2%, and non-viral cause in 86 (11.9%. There was a significant decrease in serum AFP levels from the baseline to 4 to 8 weeks after treatment (median AFP, 319.6 ng/mL vs. 49.6 ng/mL; p 1.0 was an independently associated with HCC progression or recurrence. Among the different causes of HCC analyzed, this association was significant only for HCC related to chronic hepatitis B (p< 0.001 and non-viral causes (p<0.05, and limited only to patients who had normal alanine aminotransferase (ALT levels.Serial measurements of serum AFP ratios could be helpful in detecting progression or recurrence in treated patients with HBV-HCC and normal ALT.

  4. Crystal Structures of Aedes Aegypt Alanine Glyoxylate Aminotransferase

    Energy Technology Data Exchange (ETDEWEB)

    Han,Q.; Robinson, H.; Gao, Y.; Vogelaar, N.; Wilson, S.; Rizzi, M.; Li, J.

    2006-01-01

    Mosquitoes are unique in having evolved two alanine glyoxylate aminotransferases (AGTs). One is 3-hydroxykynurenine transaminase (HKT), which is primarily responsible for catalyzing the transamination of 3-hydroxykynurenine (3-HK) to xanthurenic acid (XA). Interestingly, XA is used by malaria parasites as a chemical trigger for their development within the mosquito. This 3-HK to XA conversion is considered the major mechanism mosquitoes use to detoxify the chemically reactive and potentially toxic 3-HK. The other AGT is a typical dipteran insect AGT and is specific for converting glyoxylic acid to glycine. Here we report the 1.75{angstrom} high-resolution three-dimensional crystal structure of AGT from the mosquito Aedes aegypti (AeAGT) and structures of its complexes with reactants glyoxylic acid and alanine at 1.75 and 2.1{angstrom} resolution, respectively. This is the first time that the three-dimensional crystal structures of an AGT with its amino acceptor, glyoxylic acid, and amino donor, alanine, have been determined. The protein is dimeric and adopts the type I-fold of pyridoxal 5-phosphate (PLP)-dependent aminotransferases. The PLP co-factor is covalently bound to the active site in the crystal structure, and its binding site is similar to those of other AGTs. The comparison of the AeAGT-glyoxylic acid structure with other AGT structures revealed that these glyoxylic acid binding residues are conserved in most AGTs. Comparison of the AeAGT-alanine structure with that of the Anopheles HKT-inhibitor complex suggests that a Ser-Asn-Phe motif in the latter may be responsible for the substrate specificity of HKT enzymes for 3-HK.

  5. Alanine aminotransferase variants conferring diverse NUE phenotypes in Arabidopsis thaliana.

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    Chandra H McAllister

    Full Text Available Alanine aminotransferase (AlaAT, E.C. 2.6.1.2, is a pyridoxal-5'-phosphate-dependent (PLP enzyme that catalyzes the reversible transfer of an amino group from alanine to 2-oxoglutarate to produce glutamate and pyruvate, or vice versa. It has been well documented in both greenhouse and field studies that tissue-specific over-expression of AlaAT from barley (Hordeum vulgare, HvAlaAT results in a significant increase in plant NUE in both canola and rice. While the physical phenotypes associated with over-expression of HvAlaAT have been well characterized, the role this enzyme plays in vivo to create a more N efficient plant remains unknown. Furthermore, the importance of HvAlaAT, in contrast to other AlaAT enzyme homologues in creating this phenotype has not yet been explored. To address the role of AlaAT in NUE, AlaAT variants from diverse sources and different subcellular locations, were expressed in the wild-type Arabidopsis thaliana Col-0 background and alaat1;2 (alaat1-1;alaat2-1 knockout background in various N environments. The analysis and comparison of both the physical and physiological properties of AlaAT over-expressing transgenic plants demonstrated significant differences between plants expressing the different AlaAT enzymes under different external conditions. This analysis indicates that the over-expression of AlaAT variants other than HvAlaAT in crop plants could further increase the NUE phenotype(s previously observed.

  6. Serum γ-glutamyltransferase, alanine aminotransferase, and aspartate aminotransferase activity in Iranian healthy blood donor men

    Institute of Scientific and Technical Information of China (English)

    Hossein Khedmat; Nasrin Zarei; Farahnaz Fallahian; Hassan Abolghasemi; Bashir Hajibeigi; Zohre Attarchi; Farshid Alaeddini; Mohammad Taghi Holisaz; Masoumeh Pourali; Shahin Sharifi

    2007-01-01

    AIM: To determine serum γ-glutamyltransferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity, and to assess their correlation with demographic and clinical findings in healthy blood donors.METHODS: This cross-sectional study was performed in 934 male blood donors, aged 18 to 68 years, who consecutively attended Tehran blood transfusion service in 2006. All participants were seronegative for HBV or HCV infections, non alcohol users, and all underwent a standard interview and anthropometric tests. Clinical and biochemical parameters including AST, ALT, and GGT activities were determined. Patients taking drugs known to cause hepatic fat deposition were excluded. For AST, ALT, and GGT variables, we used 33.33 and 66.66 percentiles, so that each of them was divided into three tertiles.RESULTS: Mean AST, ALT, and GGT activities were 25.26 ± 12.58 U/L (normal range 5-35 U/L), 33.13 ± 22.98 (normal range 5-35 U/L), and 25.11 ± 18.32 (normal range 6-37 U/L), respectively. By univariate analyses, there were significant associations between increasing AST, ALT, or GGT tertiles and age, body weight, body mass index, and waist and hip circumferences (P < 0.05). By multiple linear regression analyses, ALT was found to be positively correlated with dyslipidemia (B = 6.988, P = 0.038), whereas ALT and AST were negatively correlated with age. AST, ALT, and GGT levels had positive correlation with family history of liver disease (B = 15.763, P < 0.001), (B = 32.345, P < 0.001), (B =24.415, P < 0.001), respectively.CONCLUSION: Although we did not determine the cutoffs of the upper normal limits for AST, ALT, and GGT levels, we would suggest screening asymptomatic patients with dyslipidemia and also subjects with a family history of liver disease.

  7. Normal serum alanine aminotransferase activity in uncomplicated obesity

    Institute of Scientific and Technical Information of China (English)

    Gianluca Iacobellis; Antonio Moschetta; Maria Cristina Ribaudo; Alessandra Zappaterreno; Concetta Valeria Iannucci; Frida Leonetti

    2005-01-01

    AIM: To evaluate serum alanine aminotransferase (ALT)activity in a well-characterized group of uncomplicated obese subjects and its correlation with insulin resistance,plasma adiponectin, and leptin concentrations.METHODS: One hundred and five uncomplicatedobese subjects (87 women, 18 men, age 34.3±9.6 years,BMI 39.9±8.3 kg/m2)were studied. Serum ALT activity was evaluated. Insulin sensitivity was assessed by euglycemic hyperinsulinemic clamp (M index) and fasting insulin. Plasma leptin and adiponectin levels were also measured.RESULTS: Serum ALT concentration in the whole group of uncomplicated obese subjects was 17.73±6.33 U/L with none of the subjects presenting ALT levels greater than 43 U/L and only 9 (11%) women and 3 (19%) men showed ALT levels >19 and >30 U/L for women and men,respectively. No significant difference was detected in serum ALT levels between severe obese subjects (BMI >40 kg/m2) and those with BMI <40 kg/m2 (18.63±6.25 vs 17.26±6.02 U/L). ALT was significantly correlated with fasting insulin (r = 0.485, P = 0.02) and triglycerides (r= 0.358, P= 0.03).CONCLUSION: Serum ALT activity is practically normal in uncomplicated obese subjects, independently of their obesity degree. These findings suggest the role of obesityrelated comorbidities and not of BMI as main risk factors for elevated ALT levels in obese subjects.

  8. Alanine aminotransferase, gamma-glutamyltransferase (GGT) and all-cause mortality: results from a population-based Danish twins study alanine aminotransferase, GGT and mortality in elderly twins

    DEFF Research Database (Denmark)

    Fraser, Abigail; Thinggaard, Mikael; Christensen, Kaare;

    2009-01-01

    Abstract Background/Aims: Alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) are widely used markers of liver disease. Several population-based cohort studies have found associations of these liver enzymes with all-cause mortality. None of these studies controlled for genetic...

  9. A better parameter in predicting insulin resistance: Obesity plus elevated alanine aminotransferase

    Institute of Scientific and Technical Information of China (English)

    Ping-Hao Chen; Jong-Dar Chen; Yu-Cheng Lin

    2009-01-01

    AIM: To investigate the association of obesity and elevated alanine aminotransferase with insulin resistance and compare these factors with metabolic syndrome.METHODS: We enrolled a total of 1308 male workers aged from 22 to 63 years. Data was extracted from the workers’ periodic health check-ups in hospitals. All cases were from the community of northern Taiwan.This was a cross-sectional observational study from July to September in 2004. We grouped all cases into four groups, based on the quartile of homeostasis model assessment. The top fourth quartile group was defined as the group with insulin resistance. We performed multivariate logistic regression analysis for the odds ratio of the risk factors for insulin resistance.RESULTS: Compared with metabolic syndrome, the coexistence of both factors had a 4.3-fold (95% CI: 2.7-6.8) increased risk, which was more than metabolic syndrome with a 3.6-fold (95% CI: 2.6-5.0) increased risk. The two factors had a synergistic effect. The synergistic index of obesity and elevated alanine aminotransferase (ALT) was 2.1 (95% CI: 1.01-4.3).CONCLUSION: Obesity and elevated ALT are associatedwith insulin resistance. The effects are synergistic.Coexistence of them is better than metabolic syndrome in predicting insulin resistance.

  10. Irritable Bowel Syndrome May Be Associated with Elevated Alanine Aminotransferase and Metabolic Syndrome

    OpenAIRE

    Lee, Seung-Hwa; Kim, Kyu-Nam; Kim, Kwang-Min; Joo, Nam-Seok

    2015-01-01

    Purpose Recent studies have revealed close relationships between hepatic injury, metabolic pathways, and gut microbiota. The microorganisms in the intestine also cause irritable bowel syndrome (IBS). The aim of this study was to examine whether IBS was associated with elevated hepatic enzyme [alanine aminotransferase (ALT) and aspartate aminotransferase (AST)], gamma-glutamyl transferase (γ-GT) levels, and metabolic syndrome (MS). Materials and Methods This was a retrospective, cross-sectiona...

  11. A COMPARATIVE STUDY ON THE ACTIVITY OF ALANIN-AMINOTRANSFERASE IN HYPOPHTHALMICHTHYS MOLITRIX AND ARISTICHTHYS NOBILIS

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    Gabriela Vasile

    2006-08-01

    Full Text Available The present paper represents a comparative study on the activity of one aminotransferase - alaninaminotransferase, in the digestive tube of Hypophthalmichthys molitrix (silver carp and Aristichthys nobilis (bighead carp. The enzymatic activity has been determined colorimetrically, with 2, 4 - dinitrophenyl hydrazine, the results obtained being expressed as UE / g / min. It was observed that, comparatively with the alanin-aminotransferase activity recorded in silver carp, in the case of bighead carp, the values recorded are much lower.

  12. Alanine-Glyoxylate Aminotransferase-2 Metabolizes Endogenous Methylarginines, Regulates NO, and Controls Blood Pressure

    NARCIS (Netherlands)

    Caplin, Ben; Wang, Zhen; Slaviero, Anna; Tomlinson, James; Dowsett, Laura; Delahaye, Mathew; Salama, Alan; Wheeler, David C.; Leiper, James

    2012-01-01

    Objective-Asymmetric dimethylarginine is an endogenous inhibitor of NO synthesis that may mediate cardiovascular disease. Alanine-glyoxylate aminotransferase-2 (AGXT2) has been proposed to degrade asymmetric dimethylarginine. We investigated the significance of AGXT2 in methylarginine metabolism in

  13. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Jessen, Holly Jean; Liao, Hans H; Gort, Steven John; Selifonova, Olga V

    2014-11-18

    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  14. Beta-alanine/alpha-ketoglutarate aminotransferase for 3-hydroxypropionic acid production

    Energy Technology Data Exchange (ETDEWEB)

    Jessen, Holly Jean (Chanhassen, MN); Liao, Hans H. (Eden Prairie, MN); Gort, Steven John (Apple Valley, MN); Selifonova, Olga V. (Plymouth, MN)

    2011-10-04

    The present disclosure provides novel beta-alanine/alpha ketoglutarate aminotransferase nucleic acid and protein sequences having increased biological activity. Also provided are cells containing such enzymes, as well as methods of their use, for example to produce malonyl semialdehyde and downstream products thereof, such as 3-hydroxypropionic acid and derivatives thereof.

  15. Protein Homeostasis Defects of Alanine-Glyoxylate Aminotransferase: New Therapeutic Strategies in Primary Hyperoxaluria Type I

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    Angel L. Pey

    2013-01-01

    Full Text Available Alanine-glyoxylate aminotransferase catalyzes the transamination between L-alanine and glyoxylate to produce pyruvate and glycine using pyridoxal 5′-phosphate (PLP as cofactor. Human alanine-glyoxylate aminotransferase is a peroxisomal enzyme expressed in the hepatocytes, the main site of glyoxylate detoxification. Its deficit causes primary hyperoxaluria type I, a rare but severe inborn error of metabolism. Single amino acid changes are the main type of mutation causing this disease, and considerable effort has been dedicated to the understanding of the molecular consequences of such missense mutations. In this review, we summarize the role of protein homeostasis in the basic mechanisms of primary hyperoxaluria. Intrinsic physicochemical properties of polypeptide chains such as thermodynamic stability, folding, unfolding, and misfolding rates as well as the interaction of different folding states with protein homeostasis networks are essential to understand this disease. The view presented has important implications for the development of new therapeutic strategies based on targeting specific elements of alanine-glyoxylate aminotransferase homeostasis.

  16. A novel low molecular weight alanine aminotransferase from fasted rat liver.

    Science.gov (United States)

    Vedavathi, M; Girish, K S; Kumar, M Karuna

    2006-01-01

    Alanine is the most effective precursor for gluconeogenesis among amino acids, and the initial reaction is catalyzed by alanine aminotransferase (AlaAT). Although the enzyme activity increases during fasting, this effect has not been studied extensively. The present study describes the purification and characterization of an isoform of AlaAT from rat liver under fasting. The molecular mass of the enzyme is 17.7 kD with an isoelectric point of 4.2; glutamine is the N-terminal residue. The enzyme showed narrow substrate specificity for L-alanine with Km values for alanine of 0.51 mM and for 2-oxoglutarate of 0.12 mM. The enzyme is a glycoprotein. Spectroscopic and inhibition studies showed that pyridoxal phosphate (PLP) and free -SH groups are involved in the enzymatic catalysis. PLP activated the enzyme with a Km of 0.057 mM. PMID:16487061

  17. Alanine and aspartate aminotransferase and glutamine-cycling pathway: Their roles in pathogenesis of metabolic syndrome

    Institute of Scientific and Technical Information of China (English)

    Silvia Sookoian; Carlos J Pirola

    2012-01-01

    Although new research technologies are constantly used to look either for genes or biomarkers in the prediction of metabolic syndrome (MS),the pathogenesis and pathophysiology of this complex disease remains a major challenge.Interestingly,Cheng et al recently investigated possible pathways underlying MS by high-throughput metabolite profiling in two large and well characterized community-based cohorts.The authors explored by liquid chromatography and mass spectrometry the plasma concentrations of 45distinct metabolites and examined their relation to cardiometabolic risk,and observed that metabolic risk factors such as obesity,insulin resistance (IR),high blood pressure,and dyslipidemia were associated with several metabolites,including branched-chain amino acids,other hydrophobic amino acids,tryptophan breakdown products,and nucleotide metabolites.In addition,the authors found a significant association of IR traits with glutamine,glutamate and the glutamineto-glutamate ratio.These data provide new insight into the pathogenesis of MS-associated phenotypes and introduce a crucial role of glutamine-cycling pathway as prominently involved in the development of metabolic risk.We consider that the hypothesis about the role of abnormal glutamate metabolism in the pathogenesis of the MS is certainly challenging and suggests the critical role of the liver in the global metabolic modulation as glutamate metabolism is linked with aminotransferase reactions.We discuss here the critical role of the "liver metabolism" in the pathogenesis of the MS and IR,and postulate that before fatty liver develops,abnormal levels of liver enzymes,such as alanine and aspartate aminotransferases might reflect high levels of hepatic transamination of amino acids in the liver.

  18. Isolation and characterization of cytosolic alanine aminotransferase isoforms from starved rat liver.

    Science.gov (United States)

    Vedavathi, M; Girish, K S; Kumar, M Karuna

    2004-12-01

    Alanine is the most effective precursor for gluconeogenesis among amino acids and the initial reaction is catalyzed by alanine aminotransferases (AlaATs). It is a less extensively studied enzyme under starvation and known to that the enzyme activity increases in liver under starvation. The present study describes the purification and characterization of two isoforms of alanine aminotransferases from starved male rat liver under starvation. The molecular mass of isoforms was found to be 17.7 and 112.2 kDa with isoelectric points of 4.2 and 5.3 respectively for AlaAT I and AlaAT II. Both the enzymes showed narrow substrate specificity for L-alanine with different Km for alanine and 2-oxoglutarate. Both the enzymes were glycoprotein in nature. Inhibition, modification and spectroscopic studies showed that both PLP and free-SH groups are directly involved in the enzymatic catalysis. PLP activated both the enzymes with a Km 0.057 mM and 0.2 mM for AlaAT I and II respectively. PMID:15663181

  19. Correlation between liver cell necrosis and circulating alanine aminotransferase after ischaemia/reperfusion injuries in the rat liver

    DEFF Research Database (Denmark)

    Knudsen, Anders R.; Andersen, Kasper J.; Hamilton-Dutoit, Stephen;

    2016-01-01

    performed using Pearson's correlation coefficient. Alanine transferase peaked after 4 h of reperfusion; however, at this time-point, only mild necrosis was observed, with a Pearson's correlation coefficient of 0.663 (P = 0.001). After 24 h of reperfusion, alanine aminotransferase was found to be highly...

  20. Screening for genetic haemochromatosis in blood samples with raised alanine aminotransferase

    OpenAIRE

    Bhavnani, M; Lloyd, D; Bhattacharyya, A.; Marples, J; Elton, P; Worwood, M.

    2000-01-01

    BACKGROUND—In the UK approximately 1 in 140 people are homozygous for the C282Y mutation of the HFE gene and are at risk from iron overload caused by genetic haemochromatosis (GH). Early detection can prevent organ damage secondary to iron deposition and increase life expectancy.
AIM—To screen for GH in all blood samples sent to the laboratory for routine liver function tests in which raised serum alanine aminotransferase (ALT) activity was detected.
METHODS—ALT was measured in sera sent to t...

  1. Propylthiouracyl-induced severe liver toxicity: An indication for alanine aminotransferase monitoring?

    Institute of Scientific and Technical Information of China (English)

    M Benyounes; C Sempoux; C Daumerie; J Rahier; AP Geubel

    2006-01-01

    Propylthiouracyl (PTU)-related liver toxicity is likely to occur in about 1% of treated patients. In case of acute or subacute hepatitis, liver failure may occur in about one third. We report two further cases of PTU-induced subacute hepatitis, in whom the delay between occurrence of liver damage after the initiation of treatment, the underestimation of its severity and the delayed withdrawal of the drug were all likely responsible for liver failure.The high incidence of liver toxicity related to PTU, its potential severity and delayed occurrence after initiation of treatment are in favor of monthly alanine aminotransferase monitoring, at least during the first six months of therapy.

  2. Persistent alanine aminotransferase elevation among the general Iranian population: Prevalence and causes

    Institute of Scientific and Technical Information of China (English)

    Raika Jamali; Mohammad Reza Deyhim; Houri Rezvan; Akram Pourshams; Mahmoodreza Khonsari; Shahin Merat; Masoud Khoshnia; Elham Jafari; Alireza Bahram Kalhori; Hassan Abolghasemi; Sedighe Amini; Mahtab Maghsoudlu

    2008-01-01

    AIM: To determine the prevalence and causes of persistently elevated alanine aminotransferase (ALT)levels among the general population in northern Iran.METHODS: A total of 2292 (1376 female, aged 18-75year), were selected by systematic clustered random sampling from the cities and villages of Gonbad and Kalaleh in Golestan Province and invited to participate in the study. A comprehensive history regarding alcohol drinking and medication was taken. Body mass index (BMI), viral markers and ALT levels were measured. If ALT level was ≥ 40 U/L, it was rechecked twice within 6 mo. Those with ≥ 2 times elevation of ALT were considered as having persistently elevated ALT level.Non-alcoholic fatty liver disease (NAFLD) was diagnosed based on evidence of fatty liver upon sonography and excluding other etiology.RESULTS: A total of 2049 (1351 female) patients participated in the study, 162 (7.9%) had elevated ALT level at the first measurement. Persistently elevated ALT level was detected in 64 (3.1%) participants, with 51 (79.6%) with no obvious etiology, six (9.3%) with Hepatitis B, four (6.2%) with Hepatitis C virus (HCV)infection and three (4.6%) with alcoholic hepatitis.The prevalence of NAFLD and alcoholic hepatitis was 2.04% (42 patients) and 0.1% (three), respectively.There was correlation between NAFLD and male gender,overweight, diabetes and living in an urban area [odds ratio = 3.03 (95% CI: 1.6-5.72), 4.21 (95% CI:1.83-9.68), 2.86 (95% CI: 1.05-7.79) and 2.04 (95% CI:1.00-4.16) respectively].CONCLUSION: NAFLD is the most common cause of persistently elevated serum ALT level among the general population of Iran.

  3. Effect of Terminalia Chebula (Haritaki on Serum Aspartate Aminotransferase, Alanine Aminotransferase in Paracetemol induced liver damage in Wister Albino Rats

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    Tania Yeasmin

    2015-06-01

    Full Text Available Background: Liver plays a major role in detoxification and excretion of many endogenous and exogenous compounds. Any injury may lead to severe liver damage and impairment of liver function. Harbal plants such as Terminalia chebula (Haritaki may have free radical scavenging activity thereby can be used for the prevention and treatment of liver damage. Objective: To observe the effect of Terminalia chebula on paracetamol induced changes of serum aspartate aminotransferase (AST and alanine aminotransferase (ALT in Wister albino rats. Methods: This experimental study was carried out in the Department of Physiology, Dhaka Medical College, Dhaka from January to December’ 2013. Total 44 rats with age 90 to 120 days, weighing between 150 to 200 gm were selected. After acclimatization for 14 days, they were divided into base line control (BC, n=11, paracetamol treated control (PC, n=11,Terminalia chebula pretreated and paracetamol treated (TCP-PCT n=11 and paracetamol pretreated and Terminalia chebula treated group (PCP-TCT, n=11. All groups received basal diet for 21 consecutive days. In addition to basal diet, rats of BC received propylene glycol (2ml/kg body weight, orally and PC received single dose of paracetamol suspension (750mg/kg body weight, orally on 21st day. Rats of TCP-PCT received Terminalia chebula extract (200 mg/kg body weight, orally for 21 consecutive days and paracetamol suspension (750mg/kg body weight, orally on 21st day. Again, rats of PCP-TCT received paracetamol suspension (750mg/kg body weight, orally on the 1st day and Terminalia chebula extract (200 mg/kg body weight orally for 21 consecutive days. All rats were sacrificed on 22nd day and then blood samples were collected. For assessment of liver function serum AST and ALT levels were estimated by using standard laboratory kits. The statistical analysis was done by one way ANOVA and post hoc Bonferroni test as applicable. Results: The mean serum AST and ALT levels were

  4. The investigation of the alanin-aminotransferase and aspartat-aminotransferase activity in the white rats organs on the total γ-irradiation and the physical loading

    International Nuclear Information System (INIS)

    THe investigations of enzyme activity such as aspartat aminotransferase (AST, KE 2.6.1.1.) and alanine aminotransferase (ALT, KE 2.6.1.2.) playing an important role in proteins metabolism were carried out in cell fraction of rat liver, miocard and sceleton muscle after the influence of ionizing radiation (6 Gy) and the maximum physical loading. It was shown that physical loading furthered the increases of ALT-activity in all fractions except liver cytosol. And it was noted a strongly pronounced tendency of AST-activity to lowering, except muscle cell fractions. It was shown that the physical tiredness made worse penetrated radiation action on the investigated anzymes

  5. Multiple adaptive losses of alanine-glyoxylate aminotransferase mitochondrial targeting in fruit-eating bats.

    Science.gov (United States)

    Liu, Yang; Xu, Huihui; Yuan, Xinpu; Rossiter, Stephen J; Zhang, Shuyi

    2012-06-01

    The enzyme alanine-glyoxylate aminotransferase 1 (AGT) functions to detoxify glyoxylate before it is converted into harmful oxalate. In mammals, mitochondrial targeting of AGT in carnivorous species versus peroxisomal targeting in herbivores is controlled by two signal peptides that correspond to these respective organelles. Differential expression of the mitochondrial targeting sequence (MTS) is considered an adaptation to diet-specific subcellular localization of glyoxylate precursors. Bats are an excellent group in which to study adaptive changes in dietary enzymes; they show unparalleled mammalian dietary diversification as well as independent origins of carnivory, frugivory, and nectarivory. We studied the AGT gene in bats and other mammals with diverse diets and found that the MTS has been lost in unrelated lineages of frugivorous bats. Conversely, species exhibiting piscivory, carnivory, insectivory, and sanguinivory possessed intact MTSs. Detected positive selection in the AGT of ancestral fruit bats further supports adaptations related to evolutionary changes in diet.

  6. Multiple adaptive losses of alanine-glyoxylate aminotransferase mitochondrial targeting in fruit-eating bats.

    Science.gov (United States)

    Liu, Yang; Xu, Huihui; Yuan, Xinpu; Rossiter, Stephen J; Zhang, Shuyi

    2012-06-01

    The enzyme alanine-glyoxylate aminotransferase 1 (AGT) functions to detoxify glyoxylate before it is converted into harmful oxalate. In mammals, mitochondrial targeting of AGT in carnivorous species versus peroxisomal targeting in herbivores is controlled by two signal peptides that correspond to these respective organelles. Differential expression of the mitochondrial targeting sequence (MTS) is considered an adaptation to diet-specific subcellular localization of glyoxylate precursors. Bats are an excellent group in which to study adaptive changes in dietary enzymes; they show unparalleled mammalian dietary diversification as well as independent origins of carnivory, frugivory, and nectarivory. We studied the AGT gene in bats and other mammals with diverse diets and found that the MTS has been lost in unrelated lineages of frugivorous bats. Conversely, species exhibiting piscivory, carnivory, insectivory, and sanguinivory possessed intact MTSs. Detected positive selection in the AGT of ancestral fruit bats further supports adaptations related to evolutionary changes in diet. PMID:22319153

  7. A Micro-Platinum Wire Biosensor for Fast and Selective Detection of Alanine Aminotransferase

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    Tran Nguyen Thanh Thuy

    2016-05-01

    Full Text Available In this study, a miniaturized biosensor based on permselective polymer layers (overoxidized polypyrrole (Ppy and Nafion® modified and enzyme (glutamate oxidase (GlutOx immobilized micro-platinum wire electrode for the detection of alanine aminotransferase (ALT was fabricated. The proposed ALT biosensor was measured electrochemically by constant potential amperometry at +0.7 V vs. Ag/AgCl. The ALT biosensor provides fast response time (~5 s and superior selectivity towards ALT against both negatively and positively charged species (e.g., ascorbic acid (AA and dopamine (DA, respectively. The detection range of the ALT biosensor is found to be 10–900 U/L which covers the range of normal ALT levels presented in the serum and the detection limit and sensitivity are found to be 8.48 U/L and 0.059 nA/(U/L·mm2 (N = 10, respectively. We also found that one-day storage of the ALT biosensor at −20 °C right after the sensor being fabricated can enhance the sensor sensitivity (1.74 times higher than that of the sensor stored at 4 °C. The ALT biosensor is stable after eight weeks of storage at −20 °C. The sensor was tested in spiked ALT samples (ALT activities: 20, 200, 400, and 900 U/L and reasonable recoveries (70%~107% were obtained.

  8. Healthy ranges of serum alanine aminotransferase levels in Tranian blood donors

    Institute of Scientific and Technical Information of China (English)

    Mehdi Mohamadnejad; Akram Pourshams; Reza Malekzadeh; Ashraf Mohamadkhani; Afsaneh Rajabiani; Ali Ali Asgari; Seyed Meysam Alimohamadi; Hadi Razjooyan; Mamar-Abadi

    2003-01-01

    AIM:The healthy ranges for serum alanine aminotransferase (ALT) levels are less well studied. The aim of this study was to define the upper limit of normal (ULN) for serum ALT levels, and to assess factors associated with serum ALT activity in apparently healthy blood donors.METHODS: A total of 1 939 blood donors were included.ALT measurements were performed for all cases using the same laboratory method. Healthy ranges for ALT levels were computed from the population at the lowest risk for liver disease. Univariate and multivariate analyses were performed to evaluate associations between clinical factors and ALT levels.RESULTS: Serum ALT activity was independently associated with body mass index (BMI) and male gender, but not associated with age. Association of ALT with BMI was more prominent in males than in females. Upper limit of normal for non-overweight women (BMI of less than 25) was 34 U/L,and for non-overweight men was 40 U/L.CONCLUSION: Serum ALT is strongly associated with sex and BMI. The normal range of ALT should be defined for male and female separately.

  9. Cellular and subcellular localization of hexokinase, glutamate dehydrogenase, and alanine aminotransferase in the honeybee drone retina.

    Science.gov (United States)

    Veuthey, A L; Tsacopoulos, M; Millan de Ruiz, L; Perrottet, P

    1994-05-01

    Subcellular localization of hexokinase in the honeybee drone retina was examined following fractionation of cell homogenate using differential centrifugation. Nearly all hexokinase activity was found in the cytosolic fraction, following a similar distribution as the cytosolic enzymatic marker, phosphoglycerate kinase. The distribution of enzymatic markers of mitochondria (succinate dehydrogenase, rotenone-insensitive cytochrome c reductase, and adenylate kinase) indicated that the outer mitochondrial membrane was partly damaged, but their distributions were different from that of hexokinase. The activity of hexokinase in purified suspensions of cells was fivefold higher in glial cells than in photoreceptors. This result is consistent with the hypothesis based on quantitative 2-deoxy[3H]glucose autoradiography that only glial cells phosphorylate significant amounts of glucose to glucose-6-phosphate. The activities of alanine aminotransferase and to a lesser extent of glutamate dehydrogenase were higher in the cytosolic than in the mitochondrial fraction. This important cytosolic activity of glutamate dehydrogenase was consistent with the higher activity found in mitochondria-poor glial cells. In conclusion, this distribution of enzymes is consistent with the model of metabolic interactions between glial and photoreceptor cells in the intact bee retina. PMID:8158142

  10. Associations of functional alanine-glyoxylate aminotransferase 2 gene variants with atrial fibrillation and ischemic stroke.

    Science.gov (United States)

    Seppälä, Ilkka; Kleber, Marcus E; Bevan, Steve; Lyytikäinen, Leo-Pekka; Oksala, Niku; Hernesniemi, Jussi A; Mäkelä, Kari-Matti; Rothwell, Peter M; Sudlow, Cathie; Dichgans, Martin; Mononen, Nina; Vlachopoulou, Efthymia; Sinisalo, Juha; Delgado, Graciela E; Laaksonen, Reijo; Koskinen, Tuomas; Scharnagl, Hubert; Kähönen, Mika; Markus, Hugh S; März, Winfried; Lehtimäki, Terho

    2016-01-01

    Asymmetric and symmetric dimethylarginines (ADMA and SDMA) impair nitric oxide bioavailability and have been implicated in the pathogenesis of atrial fibrillation (AF). Alanine-glyoxylate aminotransferase 2 (AGXT2) is the only enzyme capable of metabolizing both of the dimethylarginines. We hypothesized that two functional AGXT2 missense variants (rs37369, V140I; rs16899974, V498L) are associated with AF and its cardioembolic complications. Association analyses were conducted using 1,834 individulas with AF and 7,159 unaffected individuals from two coronary angiography cohorts and a cohort comprising patients undergoing clinical exercise testing. In coronary angiography patients without structural heart disease, the minor A allele of rs16899974 was associated with any AF (OR = 2.07, 95% CI 1.59-2.68), and with paroxysmal AF (OR = 1.98, 95% CI 1.44-2.74) and chronic AF (OR = 2.03, 95% CI 1.35-3.06) separately. We could not replicate the association with AF in the other two cohorts. However, the A allele of rs16899974 was nominally associated with ischemic stroke risk in the meta-analysis of WTCCC2 ischemic stroke cohorts (3,548 cases, 5,972 controls) and with earlier onset of first-ever ischemic stroke (360 cases) in the cohort of clinical exercise test patients. In conclusion, AGXT2 variations may be involved in the pathogenesis of AF and its age-related thromboembolic complications. PMID:26984639

  11. Clinical significance of serum alanine aminotransferase and lifestyle intervention in children with nonalcoholic fatty liver disease

    Science.gov (United States)

    Kwon, Kyoung Ah; Chun, Peter

    2016-01-01

    Purpose This study aimed to investigate the clinical significance of serum alanine aminotransferase (ALT) levels in children with nonalcoholic fatty liver disease (NAFLD) and the effect of lifestyle intervention on NAFLD. Methods The clinical data of 86 children diagnosed with NAFLD were reviewed retrospectively. Forty-six patients belonged to the elevated ALT group and 40 to the normal ALT group. The clinical parameters of patients with NAFLD were also compared based on the status of ALT levels after lifestyle intervention. Results Patients with elevated ALT had significantly higher body mass index (BMI) scores than those with normal ALT (P<0.05). Of all the patients with elevated ALT, 89% exhibited moderate or severe degree of fatty change in the liver on ultrasonographic examination, whereas most patients with normal ALT exhibited mild or moderate degree changes. Liver biopsy was performed in 15 children with elevated ALT and all showed mild histological changes. Of all patients with elevated ALT, 49% achieved normal ALT levels after lifestyle intervention. Those with more severe histological changes tended to have continuously increasing ALT levels. There was no correlation between the normalization of posttreatment ALT level and BMI, as well as ultrasonographic findings at diagnosis. Conclusion ALT elevation in NAFLD is highly associated with higher BMI scores and more severe degree of fatty changes on ultrasonographic examination. Lifestyle intervention can significantly improve ALT in children with NAFLD. The degree of histologic changes appears to be a predictor of the treatment response to NAFLD.

  12. Increased alanine aminotransferase levels and associated characteristics among newly diagnosed type 2 diabetes patients: Results from the DD2 study

    DEFF Research Database (Denmark)

    Mor, Anil; Thomsen, Reimar W.; Rungby, Jørgen;

    Objectives: Elevated levels of serum alanine aminotransferase (ALAT) have been linked with non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), insulin resistance and the metabolic syndrome in type 2 diabetes (T2D) patients. We examined ALAT levels in newly diagnosed T2D...... between groups. Patients in the highest ALAT quartile had more alcohol overuse (10.4% vs. 2.2% with >14/21 weekly drinks in women/men, p

  13. Reconfiguration of N Metabolism upon Hypoxia Stress and Recovery: Roles of Alanine Aminotransferase (AlaAT) and Glutamate Dehydrogenase (GDH)

    Science.gov (United States)

    Diab, Houssein; Limami, Anis M.

    2016-01-01

    In the context of climatic change, more heavy precipitation and more frequent flooding and waterlogging events threaten the productivity of arable farmland. Furthermore, crops were not selected to cope with flooding- and waterlogging-induced oxygen limitation. In general, low oxygen stress, unlike other abiotic stresses (e.g., cold, high temperature, drought and saline stress), received little interest from the scientific community and less financial support from stakeholders. Accordingly, breeding programs should be developed and agronomical practices should be adapted in order to save plants’ growth and yield—even under conditions of low oxygen availability (e.g., submergence and waterlogging). The prerequisite to the success of such breeding programs and changes in agronomical practices is a good knowledge of how plants adapt to low oxygen stress at the cellular and the whole plant level. In the present paper, we summarized the recent knowledge on metabolic adjustment in general under low oxygen stress and highlighted thereafter the major changes pertaining to the reconfiguration of amino acids syntheses. We propose a model showing (i) how pyruvate derived from active glycolysis upon hypoxia is competitively used by the alanine aminotransferase/glutamate synthase cycle, leading to alanine accumulation and NAD+ regeneration. Carbon is then saved in a nitrogen store instead of being lost through ethanol fermentative pathway. (ii) During the post-hypoxia recovery period, the alanine aminotransferase/glutamate dehydrogenase cycle mobilizes this carbon from alanine store. Pyruvate produced by the reverse reaction of alanine aminotransferase is funneled to the TCA cycle, while deaminating glutamate dehydrogenase regenerates, reducing equivalent (NADH) and 2-oxoglutarate to maintain the cycle function. PMID:27258319

  14. Reconfiguration of N Metabolism upon Hypoxia Stress and Recovery: Roles of Alanine Aminotransferase (AlaAT and Glutamate Dehydrogenase (GDH

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    Houssein Diab

    2016-05-01

    Full Text Available In the context of climatic change, more heavy precipitation and more frequent flooding and waterlogging events threaten the productivity of arable farmland. Furthermore, crops were not selected to cope with flooding- and waterlogging-induced oxygen limitation. In general, low oxygen stress, unlike other abiotic stresses (e.g., cold, high temperature, drought and saline stress, received little interest from the scientific community and less financial support from stakeholders. Accordingly, breeding programs should be developed and agronomical practices should be adapted in order to save plants’ growth and yield—even under conditions of low oxygen availability (e.g., submergence and waterlogging. The prerequisite to the success of such breeding programs and changes in agronomical practices is a good knowledge of how plants adapt to low oxygen stress at the cellular and the whole plant level. In the present paper, we summarized the recent knowledge on metabolic adjustment in general under low oxygen stress and highlighted thereafter the major changes pertaining to the reconfiguration of amino acids syntheses. We propose a model showing (i how pyruvate derived from active glycolysis upon hypoxia is competitively used by the alanine aminotransferase/glutamate synthase cycle, leading to alanine accumulation and NAD+ regeneration. Carbon is then saved in a nitrogen store instead of being lost through ethanol fermentative pathway. (ii During the post-hypoxia recovery period, the alanine aminotransferase/glutamate dehydrogenase cycle mobilizes this carbon from alanine store. Pyruvate produced by the reverse reaction of alanine aminotransferase is funneled to the TCA cycle, while deaminating glutamate dehydrogenase regenerates, reducing equivalent (NADH and 2-oxoglutarate to maintain the cycle function.

  15. Alanine aminotransferase and risk of the metabolic syndrome: a linear dose-response relationship.

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    Setor K Kunutsor

    Full Text Available BACKGROUND: Elevated baseline circulating alanine aminotransferase (ALT level has been demonstrated to be associated with an increased risk of the metabolic syndrome (MetS, but the nature of the dose-response relationship is uncertain. METHODS: We performed a systematic review and meta-analysis of published prospective cohort studies to characterize in detail the nature of the dose-response relationship between baseline ALT level and risk of incident MetS in the general population. Relevant studies were identified in a literature search of MEDLINE, EMBASE, and Web of Science up to December 2013. Prospective studies in which investigators reported relative risks (RRs of MetS for 3 or more categories of ALT levels were eligible. A potential nonlinear relationship between ALT levels and MetS was examined using restricted cubic splines. RESULTS: Of the 489 studies reviewed, relevant data were available on 29,815 non-overlapping participants comprising 2,125 incident MetS events from five prospective cohort studies. There was evidence of a linear association (P for nonlinearity=0.38 between ALT level and risk of MetS, characterised by a graded increase in MetS risk at ALT levels 6-40 U/L. The risk of MetS increased by 14% for every 5 U/L increment in circulating ALT level (95% CI: 12-17%. Evidence was lacking of heterogeneity and publication bias among the contributing studies. CONCLUSIONS: Baseline ALT level is associated with risk of the MetS in a linear dose-response manner. Studies are needed to determine whether the association represents a causal relationship.

  16. A community-based epidemiological study of elevated serum alanine aminotransferase levels in Kinmen, Taiwan

    Institute of Scientific and Technical Information of China (English)

    Chi-Ming Liu; Tao-Hsin Tung; Jorn-Hon Liu; Victor Tze-Kai Chen; Ching-Heng Lin; Chung-Te Hsu; Pesus Chou

    2005-01-01

    AIM: To explore any gender-related differences in prevalence of and condition-associated factors related to an elevated serum alanine aminotransferase (ALT) level amongst residents of Kinmen, Taiwan.METHODS: A total of 11 898 of a potential 20 112 regional residents aged 30 years or more completed a related questionnaire that was carried out by the Yang-Ming Crusade between 1991 and 1994 inclusively, with blood samples being collected by public nurses. The overall questionnaire response rate was 59.3% (52.4% for males and 66.0% for females).RESULTS: The prevalence of an elevated serum ALT level for this sub-population was found to be 7,2%, the prevalence revealing a statistically significant decrease with increasing population age (P<0.0001). Males exhibited a greater prevalence of elevated serum ALT level than did females (9.4% vs 5.3%, P<0.0001). Using multiple logistic regression analysis, in addition to male gender, a younger age, greater waist circumference,presence of type-2 diabetes and hyperuricemia were the significant factors associated with an elevated serum ALT level for both males and females. Gender-related differences as regards associated factors were also revealed. For males, obesity was significantly related to an elevated serum ALT level (OR = 1.28, 95%CI: 1.00-1.66)but this was not so for females (OR = 1.09, 95%CI:0.84-1.42). Hypertriglyceridemia (OR = 1.80, 95%CI:1.36-2.39) and hyperuricemia (OR = 1.61, 95%CI:1.03-2.52) were significantly related to elevated serum ALT levels only for females.CONCLUSION: Several gender-related differences were noted pertaining to the prevalence of and relationship between obesity, hypertriglyceridemia and hyperuricemia and elevated serum ALT level in the present study.(c)2005 The WJG Press and Elsevier Ihc. All rights reserved.

  17. Relationship between alanine aminotransferase levels and metabolic syndrome in nonalcoholic fatty liver disease

    Institute of Scientific and Technical Information of China (English)

    Zhou-wen CHEN; Li-ying CHEN; Hong-lei DAI; Jian-hua CHEN; Li-zheng FANG

    2008-01-01

    Objective:To investigate the relationship between alanine aminotransferase (ALT)levels and metabolic syndrome (MS)in nonalcoholic fatty liver disease(NAFLD).Methods:A total of 26527 subjects who received medical health checkup in our hospital from January 2005 to July 2007 were enrolled in the study.The diagnosis of fatty liver was based on ultrasound imaging.MS Was defined according to the criteria of the Adult Treatment Panel Ⅲ.ALT,triglyceride(TG),high density lipoprotein cholesterol(HDL-c),fasting plasma glucose(FPG),height,weight,waist circumference(WC),systolic blood pressure (SBP)and diastolic blood pressure(DBP)were measured in each subject to analyze the relationship between MS and ALT activity.Results:(1)The prevalence of NAFLD in men(30.94%)was significantly higher than that in women(15.65%);(2)The incidence of MS in NAFLD(33.83%)was significantly greater than that in non-NAFLD(10.62%);(3)Of the 6470 subjects with NAFLD,in the age-adjusted partial correlation analysis,there were statistically significant correlations between the ALT levels and most metabolic risk factors in each sex(P<0.01),except that ALT levels had no correlation with HDL-c in women.Moreover,in the multiple stepwise regression analysis,SBP lost its significance,and WC,body mass index(BMI),age,DBP,TG and FPG were independently associated with ALT levels in both sexes (P<0.05).HDL-c remained significant and was independently related to ALT leveis in men;(4)ALT levels were significantly higher in subjects with MS compared to those without MS(P<0.001).Mean ALT levels increased with the number of MS cornponents in each sex (P.<0.05 for trend).Conelusion:We found a strong relationship between ALT leveIs and MS in NAFLD and revealed that the cluster of MS components might be the predictor for ALT elevations.

  18. High alanine aminotransferase is associated with decreased hepatic insulin sensitivity and predicts the development of type 2 diabetes

    DEFF Research Database (Denmark)

    Vozarova, Barbora; Stefan, Norbert; Lindsay, Robert S;

    2002-01-01

    It has been proposed that liver dysfunction may contribute to the development of type 2 diabetes. The aim of the present study was to examine whether elevated hepatic enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], or gamma -glutamyltranspeptidase [GGT]) are associated...... with prospective changes in liver or whole-body insulin sensitivity and/or insulin secretion and whether these elevated enzymes predict the development of type 2 diabetes in Pima Indians. We measured ALT, AST, and GGT in 451 nondiabetic (75-g oral glucose tolerance test) Pima Indians (aged 30 +/- 6 years, body fat......-sectionally associated with obesity and whole-body and hepatic insulin resistance and prospectively associated with a decline in hepatic insulin sensitivity and the development of type 2 diabetes. Our findings indicate that high ALT is a marker of risk for type 2 diabetes and suggest a potential role of the liver...

  19. Association of Serum Alanine Aminotransferase Levels with Cardiometabolic Risk Factors in Normal-Weight and Overweight Children

    Directory of Open Access Journals (Sweden)

    Atoosa Adibi

    2011-09-01

    Full Text Available Objective:This study aimed to determine the prevalence of increased alanine aminotransferase (ALT, defined by a gender-specific cutoff value, among normal weight and overweight children; and to assess the relationship of increasing ALT levels with cardiometabolic risk factors. Methods:This cross-sectional study was conducted among school students, aged 6-18 years in Isfahan, Iran. Based on the body mass index (BMI percentiles, a group of normal-weight was compared with a group of overweight and obese students. Gender differences were considered for increased levels of ALT, i.e. 19U/L and 30U/L for girls and boys respectively. Findings:The study participants consisted of 1172 students (56.2% girls, with a mean (SD age of 12.57 (3.3 years. Among overweight/obese students the mean triglycerides (TG and diastolic blood pressure was significantly higher in those with increased ALT than in those with normal ALT levels. The logistic regression analysis showed that among overweight/obese boys, for each 1 unit increase in ALT, the odds ratio (OR of TG, total cholesterol and systolic blood pressure increased significantly. After adjusting for age, these associations remained significant, and the OR of high density lipoprotein cholesterol (HDL-c decreased significantly. In the model adjusting for age and BMI, the ORs of TG and HDL-c remained significant. After adjusting for age and waist circumference, HDL-c was the only parameter with significant OR. Among overweight/obese girls, in all models applied, the OR was significant for TG and total cholesterol. A significant independent association was documented for waist circumference and increase in ALT after adjustment for BMI. Conclusion:This study documented significant relationship of increased ALT levels, defined by a gender-specific cutoff point, with cardiometabolic risk factors and hypertriglyceridemic-waist phenotype in Iranian children and adolescents.

  20. Effect of heavy metals (Cu, Cd and Pb) on aspartate and alanine aminotransferase in Ruditapes philippinarum (Mollusca: Bivalvia)

    Energy Technology Data Exchange (ETDEWEB)

    Blasco, J.; Puppo, J. [Instituto de Ciencias Marinas de Andalucia, Campus Univ. Rio S. Pedro, 11510 Puerto Real, Cadiz (Spain)

    1999-02-01

    The accumulation of cadmium, copper and lead and their effects on aspartate and alanine aminotransferases in digestive gland, gills, foot and soft body in the clam Ruditapes philippinarum were examined. The animals were exposed to different concentrations: Cd (200-600 {mu}g{center_dot}l{sup -1}), Pb (350-700 {mu}g{center_dot}l{sup -1}) and Cu (10-20 {mu}g{center_dot}l{sup -1}) for 7 days. The highest concentrations were found in digestive gland for cadmium and copper, and in gills for lead, and the lowest values were observed in the foot. Aspartate aminotransferase activity (AST), in general, was not inhibited by cadmium, lead or copper during the exposure. Only in clams exposed to cadmium (600 {mu}g{center_dot}l{sup -1}, 7 days) and copper (20 {mu}g{center_dot}l{sup -1}, 5 days) were observed significant differences (P<0.05) in foot and gills, respectively, with respect to control. In the case of alanine aminotransferase activity (ALT), significant differences were observed for cadmium and lead in treated animals with respect to control. With regard to copper, a decrease in ALT was observed in gills and foot exposed to 20 {mu}g{center_dot}l{sup -1}. A significant correlation (P<0.05) was observed between ALT and metal accumulation for cadmium, copper and lead in gills. In the case of soft body, only cadmium and lead showed a significant correlation. In summary, R. philippinarum can be considered a bioindicator species for cadmium and lead accumulation and ALT could be useful as biomarker of sublethal stress for these metals in soft tissues and gills. Only gills can be considered an adequate target tissue for copper. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Effect of streptococcal preparation (picibanil on the postoperative rise in serum alanine aminotransferase activity in patients with urogenital cancer.

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    Taketa,Kazuhisa

    1980-12-01

    Full Text Available The effect of Picibanil, a streptococcal agent, on the development of liver injury after operations for urogenital cancer was studied retrospectively in the light of serum alanine aminotransferase (ALT activity. The series comprised 32 cases receiving Picibanil and 33 controls with otherwise comparable clinical backgrounds. Picibanil reduced the incidence of postoperative ALT rise over 50 U/l within 6 weeks but increased it thereafter. The increase in ALT activity after 6 weeks was relatively small and was seen more often in patients given blood transfusions. It was interpreted as retardation and suppression of ALT rise and as being related to the induction of interferon or to immunopotentiation. Other antihepatotoxic effects of Picibanil, due to its antioxidant activity, for example, may also account for the prevention of the early postoperative rise in ALT activity.

  2. Impact of elevated aspartate and alanine aminotransferase on metabolic syndrome and its components among adult people living in Ningxia, China

    Institute of Scientific and Technical Information of China (English)

    Kun-Peng He; Chuan Zhao; Yan Qiang; He-Rong Liu; Nan Chen; Xiu-Juan Tao; Li-Li Chen; Hui Song

    2015-01-01

    Objective: Metabolic syndrome (MS) is a combination of medical disorders that increase the risk for cardiovascular disease and diabetes mellitus. It suggests an association between an elevated serum aminotransferase level and MS. Little data show the relationship between the levels of serum aminotransferase and the incidence of MS in Ningxia, China. Methods: A total of 5415 subjects who received medical health checkups from 2007 to 2009 were enrolled in the study. The participants were interviewed by trained health workers under a structured questionnaire. MS was defined according to the modified ATPIII criteria for Asian Americans by the American Heart Association (AHA-ATP III). Results: The prevalence of elevated aspartate aminotransferase (AST) and ALT (>40 U/L) were 7.1%and 22.2%in males, and 2.1%and 4.8%in females respectively. The prevalence of MS was 32.1%in males and 15.4%in females. The components of MS were significantly more in the group with elevated aminotransferase levels than in the group with normal amino-transferase levels. The odds ratios (95%CI) for elevated AST were 1.90 (1.49, 2.42), 2.59 (2.01, 3.39), 1.68 (1.32, 2.15), and 1.81 (1.36, 2.42) in the adults with abdominal obesity, high serum triglycerides levels, high blood pressure, and high plasma glucose levels respectively. After adjustment for age, the odds ratios (95%CI) for elevated ALT were 3.08 (2.63, 3.61), 4.30 (3.64, 5.08), 1.26 (1.08, 1.48), 2.16 (1.93, 2.65) and 2.38 (1.96, 2.87) in adults with abdominal obesity, high serum tri-glycerides levels, low serum high-density lipoproteincholesterol (HDL-C), high blood pressure, and high plasma glucose levels respectively. The odds ratios (95%CI) for elevated AST were 1.67 (1.06, 2.63), 2.28 (1.46, 3.63), 2.59 (1.59, 4.21) and for elevated ALT 2.02 (1.50, 2.73), 2.68 (1.96, 3.65), 3.94 (2.86, 5.43) for the subjects with 1, 2, and ?3 risk factors after adjustment for age, gender, and BMI. Conclusion: The serum aminotransferase levels were

  3. The Association of Elevated Serum Alanine Aminotransferase with Metabolic Syndrome in A Military Population in Southern Iran

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    B Sabayan

    2010-06-01

    Full Text Available Background: Metabolic syndrome (MetS is rapidly rising at an alarming rate through all parts of the world. Elevated serum aminotransferase was proposed as a marker for early detection of MetS. In this investigation we primarily aimed to evaluate the prevalence of MetS and its components among army and secondly to explore the association between elevated serum aminotransferase and the components of metabolic syndrome. Methods: A total of 380 army personnel from a military camp in Southern Iran participated in this cross-sectional study. Life style related characteristics, anthropometric features, serum aminotransferase and components of MetS, based on National Cholesterol Education Program—Adult Treatment Panel III, were measured. Statistical significant was set as p value less than 0.05. Results: The mean age of participants was 35.0± 7.5 year-old and the prevalence of metabolic syndrome was 8.1%. The prevalence of the components of MetS including; central obesity, abnormal fasting blood glucose, hypertension, hypertriglycridemia and low HDL cholesterol level was 8.6%, 10.4%, 18.5%, 31%, and 45.5% respectively. MetS had significant relationship with obesity (P<0.001 and abnormal Waist Circumferance/Hip Circumference ratio (P<0.001. Twenty-six percent of subjects had ALT ≥ 41 U/L and 4.9% of them had ALT ≥ 81. Elevated serum aminotransferase had significant association with presence of MetS (P= 0.007. Conclusion: Although prevalence of metabolic syndrome among the studied army population was not high, life style modification of army members is recommended. Liver function tests should be included in routine health checkup of military personnel.

  4. Correlation between Aminotransferase Ratio (AST/ALT and Other Biochemical Parameters in Chronic Liver Disease of Viral Origin

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    Shah Md Fazlul Karim

    2015-03-01

    Full Text Available Background: In recent years the ratio of aspartate aminotransferase (AST to alanine aminotransferase (ALT in patients of chronic liver disease (CLD of various origins has gained much attention. This variable is readily available, easy to interpret, and inexpensive and the clinical utility of the AST/ALT ratio in the diagnostic workup of patients with CLD is quite promising. Objective: The present study was designed to find out the link between aminotransferase (AST/ALT ratio with commonly measured biochemical parameters of liver function tests in CLD of viral origin. Materials and method: This cross sectional study was carried out in the department of Biochemistry, Sir Salimullah Medical College, Dhaka, Bangladesh. Forty four biopsy proven diagnosed subjects of chronic viral hepatitis without cirrhosis of both sex were selected purposively. With aseptic precaution 5 mL venous blood was collected from each subject and common liver function tests (serum AST, ALT, AST/ALT ratio, alkaline phosphatase, total bilirubin, serum total protein, serum albumin, serum globulin, serum albumin/globulin ratio, prothrombin time and viral serology (HBsAg, Anti HDV antibody, Anti HCV antibody were performed. Data were analyzed by SPSS version 19 for Windows. Pearson’s correlation test was done to determine association between AST/ALT with other biochemical parameters. Results: Mean(±SD age of the study subjects was 32.55±10.55 years (range 20-50 years with 48 (77.7% male and 14 (22.6% female subjects. Pearson’s correlation test was done between AST to ALT ratio with other biochemical parameters and prothrombin time showed significant positive correlation (p <0.01. Conclusion: In our study we found significant positive correlation between AST/ALT with prothrombin time in CLD subjects without cirrhosis.

  5. Hubungan Kadar Trigliserida dan Kolesterol-HDL Terhadap Kadar Alanine Aminotransferase pada Pasien Non Alcoholic Fatty Liver Disease

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    Bayu Gemilang

    2016-01-01

    Full Text Available AbstrakTrigliserida dan Kolesterol HDL (c-HDL merupakan beberapa dari komponen Sindroma Metabolik (SM. SM dipercaya merupakan faktor utama penyebab Non Alcoholic Fatty Liver Disease (NAFLD. NAFLD merupakan penyakit hati kronik yang nantinya dapat menyebabkan fibrosis sel-sel hepar dan juga keganasan. NAFLD tidak menunjukkan manifestasi klinis yang khas, sehingga diperlukan pemeriksaan penunjang seperti pemeriksaan enzim hati untuk menegakkan diagnosis. Alanine Aminotransferase (ALT menjadi pilihan sebagai marker pada penyakit NAFLD. Tujuan penelitian ini adalah menentukan hubungan antara trigliserida dan c-HDL dengan ALT pada penderita NAFLD. Ini merupakan penelitian analitik deskriptif dengan desain retrospektif menggunakan data pasien NAFLD di instalasi rekam medik RSUP dr.M.Djamil Padang. Sampel penelitian ini adalah 51 pasien NAFLD. Hasil penelitian didapatkan dari uji korelasi pearson terdapat derajat hubungan yang kuat (r=0,512 dan hubungan yang bermakna (p<0,001 antara kadar trigliserida dengan kadar ALT serum dan derajat hubungan yang sedang (r=0,26 dan hubungan yang tidak bermakna (p=0,065 antara c-HDL dengan ALT serum. Kesimpulan penelitian ini adalah kadar ALT berhubungan dengan kadar trigliserida pada penderita NAFLD, namun tidak dengan c-HDLKata kunci: NAFLD, trigliserida, HDL, ALT, sindroma metabolik AbstractTriglyceride and HDL Cholesterol (HDL-C are some of the Metabolic Syndrome (MS components. MS is believed as the main factor for the Non Alcoholic Fatty Liver Disease (NAFLD. NAFLD is a chronic liver disease, which later can cause hepatocyte fibrosis and also malignancy. NAFLD does not show a typical clinical appearance, so it is important to do workups such as liver enzyme test to make the diagnosis. Alanine Aminotransferase (ALT is considered as the marker of NAFLD.The objective of this study was to determine the relationship between triglycerides and HDL-C to ALT level in NAFLD patients.This  was a descriptive analytical

  6. Peroxisomal alanine: glyoxylate aminotransferase AGT1 is indispensable for appressorium function of the rice blast pathogen, Magnaporthe oryzae.

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    Vijai Bhadauria

    Full Text Available The role of β-oxidation and the glyoxylate cycle in fungal pathogenesis is well documented. However, an ambiguity still remains over their interaction in peroxisomes to facilitate fungal pathogenicity and virulence. In this report, we characterize a gene encoding an alanine, glyoxylate aminotransferase 1 (AGT1 in Magnaporthe oryzae, the causative agent of rice blast disease, and demonstrate that AGT1 is required for pathogenicity of M. oryzae. Targeted deletion of AGT1 resulted in the failure of penetration via appressoria; therefore, mutants lacking the gene were unable to induce blast symptoms on the hosts rice and barley. This penetration failure may be associated with a disruption in lipid mobilization during conidial germination as turgor generation in the appressorium requires mobilization of lipid reserves from the conidium. Analysis of enhanced green fluorescent protein expression using the transcriptional and translational fusion with the AGT1 promoter and open reading frame, respectively, revealed that AGT1 expressed constitutively in all in vitro grown cell types and during in planta colonization, and localized in peroxisomes. Peroxisomal localization was further confirmed by colocalization with red fluorescent protein fused with the peroxisomal targeting signal 1. Surprisingly, conidia produced by the Δagt1 mutant were unable to form appressoria on artificial inductive surfaces, even after prolonged incubation. When supplemented with nicotinamide adenine dinucleotide (NAD(++pyruvate, appressorium formation was restored on an artificial inductive surface. Taken together, our data indicate that AGT1-dependent pyruvate formation by transferring an amino group of alanine to glyoxylate, an intermediate of the glyoxylate cycle is required for lipid mobilization and utilization. This pyruvate can be converted to non-fermentable carbon sources, which may require reoxidation of NADH generated by the β-oxidation of fatty acids to NAD(+ in

  7. Diet and the frequency of the alanine:glyoxylate aminotransferase Pro11Leu polymorphism in different human populations.

    Science.gov (United States)

    Caldwell, Elizabeth F; Mayor, Lianne R; Thomas, Mark G; Danpure, Christopher J

    2004-11-01

    The intermediary metabolic enzyme alanine:glyoxylate aminotransferase (AGT) contains a Pro11Leu polymorphism that decreases its catalytic activity by a factor of three and causes a small proportion to be mistargeted from its normal intracellular location in the peroxisomes to the mitochondria. These changes are predicted to have significant effects on the synthesis and excretion of the metabolic end-product oxalate and the deposition of insoluble calcium oxalate in the kidney and urinary tract. Based on the evolution of AGT targeting in mammals, we have previously hypothesised that this polymorphism would be advantageous for individuals who have a meat-rich diet, but disadvantageous for those who do not. If true, the frequency distribution of Pro11Leu in different extant human populations should have been shaped by their dietary history so that it should be more common in populations with predominantly meat-eating ancestral diets than it is in populations in which the ancestral diets were predominantly vegetarian. In the present study, we have determined frequency of Pro11Leu in 11 different human populations with divergent ancestral dietary lifestyles. We show that the Pro11Leu allelic frequency varies widely from 27.9% in the Saami, a population with a very meat-rich ancestral diet, to 2.3% in Chinese, who are likely to have had a more mixed ancestral diet. FST analysis shows that the differences in Pro11Leu frequency between some populations (particularly Saami vs Chinese) was very high when compared with neutral loci, suggesting that its frequency might have been shaped by dietary selection pressure.

  8. Peginterferon alfa-2a is associated with elevations in alanine aminotransferase at the end of treatment in chronic hepatitis C patients with sustained virologic response.

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    Chih-Wei Tseng

    Full Text Available The purpose of this study was to investigate the incidence and demographic/clinical factors of alanine aminotransferase (ALT abnormalities at the end of treatment (EOT in chronic hepatitis C (CHC patients with sustained virologic response (SVR.Seven hundred naïve CHC patients who underwent combination treatment between January 2003 and December 2010 were included in the study. The patients with SVR and serum ALT>upper limit of normal (ULN at the EOT were further analyzed. The effects of clinical characteristics, treatment regimen, and virologic variables were evaluated by logistic regression. Of the 700 included patients, 488 (69.7% achieved an SVR after treatment, and 235 (33.6% had serum ALT levels>ULN at the EOT. Of those 488 patients, 137 (28.1% had abnormal ALT values at the EOT. A multivariate analysis showed that the occurrence of ALT abnormalities at the EOT was significantly associated with pegylated interferon (PEG-IFN alfa-2a (odds ratio [OR], 2.24; 95% confidence interval [CI], 1.45-3.45; P<0.001, baseline fatty liver (OR, 1.76; 95% CI, 1.16-2.76; P = 0.007, and baseline liver cirrhosis (OR, 2.35; 95% CI, 1.35-4.09; P = 0.002.Use of PEG-IFN-alfa-2a, fatty liver, and cirrhosis are important factors associated with EOT-ALT abnormality in CHC patients receiving combination therapy that achieve an SVR. PEG-IFN-alfa-2a-related EOT-ALT elevation will become normal at the end of follow-up, but fatty liver and cirrhosis-related ALT elevation will not be resolved.

  9. The efficacy of aspartate aminotransferase-toplatelet ratio index for assessing hepatic fibrosis in childhood nonalcoholic steatohepatitis for medical practice

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    Earl Kim

    2013-01-01

    Full Text Available Purpose: Childhood obesity is associated with nonalcoholic fatty liver disease (NAFLD, and it has become one of the most common causes of childhood chronic liver diseases which significant as a cause of liver related mortality and morbidity in children in the United States. The development of simpler and easier clinical indices for medical practice is needed to identify advanced hepatic fibrosis in childhood NAFLD instead of invasive method like liver biopsy. FibroScan and aspartate aminotransferase (AST-to-platelet ratio index (APRI have been proposed as a simple and noninvasive predictor to evaluate hepatic fibrosis in several liver diseases. APRI could be a good alternative to detect pathologic change in childhood NAFLD. The purpose of this study is to validate the efficacy of APRI for assessing hepatic fibrosis in childhood NAFLD based on FibroScan. Methods: This study included 23 children with NAFLD who underwent FibroScan. Clinical, laboratory and radiological evaluation including APRI was performed. To confirm the result of this study, 6 patients received liver biopsy. Results: Factors associated with hepatic fibrosis (stiffness measurement &gt;5.9 kPa Fibroscan were triglyceride, AST, alanine aminotransferase, platelet count, APRI and collagen IV. In multivariate analysis, APRI were correlated with hepatic fibrosis (&gt;5.9 kPa. In receiver operating characteristics curve, APRI of meaningful fibrosis (cutoff value, 0.4669; area under the receiver operating characteristics, 0.875 presented sensitivity of 94%, specificity of 66%, positive predictive value of 94%, and negative predictive value of 64%. Conclusion: APRI might be a noninvasive, simple, and readily available method for medical practice to predict hepatic fibrosis of childhood NAFLD.

  10. Complex association between alanine aminotransferase activity and mortality in general population: a systematic review and meta-analysis of prospective studies.

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    Zhengtao Liu

    Full Text Available OBJECTIVE: Controversy exists in using alanine aminotransferase (ALT activity for predicting long-term survival. Therefore, this research study investigated the association between ALT activity and mortality through a systematic review and meta-analysis of previous prospective studies. METHODS: Electronic literature databases, including PubMed, Embase, and the Institute for Scientific Information (ISI, were searched for relevant prospective observational studies (published before Dec 30, 2013 on the association between baseline ALT activity and ensuing all-cause/disease-specific mortality. Information on nationality, sample size, participant characteristics, follow-up duration, comparison, outcome assessment, hazard ratios (HRs and adjusted covariates was extracted. Pooled HRs and corresponding 95% confidence intervals (CIs were separately calculated for categorical risk estimates (highest vs. lowest ALT categories and continuous risk estimates (per 5 U/l of ALT increment in subgroups separated by age (<70/≥ 70 years. RESULTS: A total of twelve prospective cohort studies, totaling 206,678 participants and 16,249 deaths, were identified and analyzed. In the younger age group, the pooled HR for mortality related to liver-disease was about 1.24 (95% CI: 1.23-1.25 per 5 U/l of ALT increment. The dose-response HRs of all-cause mortality, cardiovascular (CV disease-related mortality, and cancer-related mortality were 0.91 (0.88-0.94, 0.91 (0.85-0.96, 0.92 (0.86-0.98 respectively per 5 U/l of ALT elevation, with insignificant heterogeneity in the older population. There was an approximate decrease of 4‰ observed on HRs of all-cause, CV-related, and cancer-related mortality followed with one year's increment through meta-regression (all P<0.05. CONCLUSIONS: The ALT-mortality association was inconsistent and seems particularly susceptible to age after synthesizing the previous prospective studies. In terms of the age, ALT activity was more valuable

  11. Comparison of measurements of canine plasma creatinine, glucose, proteins, urea, alanine aminotransferase, and alkaline phosphatase obtained with Spotchem SP 4430 and Vitros 250 analyzers.

    Science.gov (United States)

    Trumel, C; Diquélou, A; Germain, C; Palanché, F; Braun, J P

    2005-12-01

    The suitability of the Spotchem 4430 benchtop biochemistry analyzer for canine blood samples was tested for creatinine, glucose, proteins, urea, alkaline phosphatases and alanine aminotransferase. Results obtained from whole blood and corresponding heparin plasma were identical except for proteins which were higher in plasma (n=10). Between series imprecision (n=10) was 0.93). The slopes of the Passing-Bablock's regression ranged from 0.90 to 1.20 and intercepts were low. The mean biases were low, except for creatinine for which the results obtained by Spotchem (Jaffe reaction) were about 20 micromol/L higher than with the Vitros (enzymatic reaction). The results of this study show that the Spotchem analyzer is suitable for use in canine whole blood or plasma when small numbers of tests are to be performed and large analyzers are not available. PMID:16054888

  12. Structural implications of a G170R mutation of alanine:glyoxylate aminotransferase that is associated with peroxisome-to-mitochondrion mistargeting

    International Nuclear Information System (INIS)

    The crystal structure of the G170R mutant form of human alanine:glyoxylate aminotransferase has been determined at 2.6 Å resolution. This mutation is associated with enzyme mistargeting in the hereditary kidney-stone disease primary hyperoxaluria type 1. In a subset of patients with the hereditary kidney-stone disease primary hyperoxaluria type 1 (PH1), the liver-specific enzyme alanine:glyoxylate aminotransferase (AGT) is mistargeted from peroxisomes to mitochondria. This is a consequence of the combined presence of the common P11L polymorphism and a disease-specific G170R mutation. In this paper, the crystal structure of mutant human AGT containing the G170R replacement determined at a resolution of 2.6 Å is reported. The crystal structure of AGT consists of an intimate dimer in which an extended N-terminal segment of 21 amino acids from one subunit wraps as an elongated irregular coil around the outside of the crystallographic symmetry-related subunit. In addition to the N-terminal segment, the monomer structure contains a large domain of 261 amino acids and a small C-terminal domain of 110 amino acids. Comparison of the mutant AGT structure and that of wild-type normal AGT shows that the two structures are almost identical, with a backbone-atom r.m.s. deviation of 0.34 Å. However, evidence of significant local structural changes in the vicinity of the G170R mutation might be linked to the apparent decrease in protein stability

  13. Correlation of hepatitis C RNA and serum alanine aminotransferase in hepatitis B and C seronegative healthy blood donors

    OpenAIRE

    Ali Natasha; Moiz Bushra; Moatter Tariq; Ahmed Shiraz; Adil Salman; Khurshid Mohammad

    2010-01-01

    Introduction: Historically, serum alanine transaminase (ALT) has been used as a surrogate marker in the detection of hepatitis viruses in blood donors. With the availability of newer sensitive technologies for the detection of seroconversion, the value of ALT becomes questionable but continues to be used for this purpose with subsequent discarding of ALT elevated blood units. Objective: The present study aims to evaluate the significance and cost effectiveness of ALT as a surrogate marker for...

  14. Modifiable clinical and lifestyle factors are associated with elevated alanine aminotransferase levels in newly diagnosed type 2 diabetes patients

    DEFF Research Database (Denmark)

    Mor, Anil; Svensson, Elisabeth; Rungby, Jørgen;

    2014-01-01

    BACKGROUND: Current literature lacks data on markers of non-alcoholic fatty liver disease (NAFLD) in newly diagnosed type 2 diabetes mellitus (T2DM) patients. We therefore, conducted a cross-sectional study to examine modifiable clinical and lifestyle factors associated with elevated alanine....../>21 drinks per week for women/men) (aPR: 1.60, 95% CI: 1.03-2.50), and in those with no regular physical activity (aPR: 1.42, 95% CI: 1.04-1.93). Obesity and metabolic syndrome per se showed no association with elevated ALT when adjusted for other markers, whereas we found positive associations of ALT...

  15. The effect of pyridoxal-5-phosphate on serum alanine aminotransferase activity in dogs suffering from canine babesiosis

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    E.C. Myburgh

    2009-09-01

    Full Text Available Accurate measurements of serum aminotransferase (ALT activity in dogs relies on the endogenous pro-enzyme pyridoxal 5-phosphate (P5P. The purpose of this study was to determine whether the exclusion of P5P from the analytical method causes an underestimation of serum ALT activity in dogs suffering from babesiosis and in those manifesting evidence of hepatocellular damage, and to determine if anorexia causes sufficient P5P depletion to affect in vitro serum ALT activity. One-hundred-and-twenty healthy control dogs and 105 Babesia-infected dogs were included in the study. Two methods for ALT measurement were used: Method 1 included P5P, and Method 2 excluded P5P from the reaction mixture. Higher serum ALT activity was measured with Method 1 in the Babesia-infected dogs (P < 0.001, as well as in 14 dogs with suspected hepatocellular damage (P = 0.03. Duration of anorexia had no effect, irrespective of the method used. Although inclusion of P5P to the reaction mixture consistently resulted in higher measured serum ALT activity, the differences were too small to have led to incorrect diagnoses in the Babesia-infected dogs suspected of liver disease.

  16. The association between non-alcoholic fatty liver disease and carotid atherosclerosis in subjects with within-reference range alanine aminotransferase levels.

    Science.gov (United States)

    Kim, Kyung-Soo; Oh, Hyun-Ju; Kim, Dae-Jung; Kim, Soo-Kyung; Park, Seok Won; Cho, Yong-Wook; Huh, Kap-Bum

    2013-01-01

    Our aim was to investigate whether the evaluation of non-alcoholic fatty liver disease (NAFLD) by ultrasound provides additional benefit in assessing carotid atherosclerotic burden in subjects with alanine aminotransferase (ALT) concentrations within the reference range. This was a cross-sectional analysis of 769 healthy individuals (326 men and 443 women) with an ALT concentration ≤ 40 IU/L and alcohol consumption range, the prevalence of NAFLD increased with increasing quartiles of ALT concentration (27.1%, 40.0%, 54.7%, 75.3% in men, P for trend 4th quartiles of ALT concentration, women with NAFLD had a significantly higher C-IMT than those without NAFLD (0.671±0.019 mm vs. 0.742±0.025 mm, P=0.023 in Q3; 0.651±0.023 mm vs. 0.737±0.021 mm, P=0.005 in Q4). These differences remained significant even after adjusting for a broad spectrum of potential confounders. In contrast, although men with NAFLD tended to have a higher C-IMT than those without NAFLD in each quartile, these differences were not statistically significant. Women with an upper normal range ALT concentration showed increased C-IMT only when they had NAFLD. Therefore, in women with an elevated ALT level within the reference range, further evaluation for NAFLD, such as liver ultrasound, could potentially identify those patients at high risk for cardiovascular disease.

  17. Correlation of hepatitis C RNA and serum alanine aminotransferase in hepatitis B and C seronegative healthy blood donors

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    Ali Natasha

    2010-07-01

    Full Text Available Introduction: Historically, serum alanine transaminase (ALT has been used as a surrogate marker in the detection of hepatitis viruses in blood donors. With the availability of newer sensitive technologies for the detection of seroconversion, the value of ALT becomes questionable but continues to be used for this purpose with subsequent discarding of ALT elevated blood units. Objective: The present study aims to evaluate the significance and cost effectiveness of ALT as a surrogate marker for hepatitis C virus infection in healthy asymptomatic blood donors who were serologically negative. Materials and Methods: The study was conducted at clinical laboratory of a tertiary care hospital for a period of one year from November 2006 to October 2007. All donors were screened serologically for hepatitis B, C and HIV I and II, syphilis and malaria and those tested positive were excluded from further evaluation. Gender-wise reference ranges and minimal and markedly raised results for ALT (described respectively as one and two folds increase above reference range were defined and, accordingly, donors were grouped into three. Two hundred seronegative blood donors were randomly selected from all three groups of ALT results and tested for hepatitis C nucleic acid through Amplicor; HCV RNA test. The cost of discarding an ALT -only elevated blood unit was also assessed. During the study period, 25117 subjects donated blood. Eight hundred and Results: seventy two donors (3.4% were positive for one or more serological tests. ALT of all donors ranged from 0-1501 U/L (Mean ± SD; 33.4 ± 25.45U/L. The donors seronegative for all disease markers were 24245 (96.6%. Of these, 21164 (87.2% donors had their ALT within reference range while 2874 (11.8% and 207 (0.8% of donors had minimal and markedly elevated results. Thus, 621 blood bags (red cells, platelets and plasma costing $ 39200.0 were discarded based on ALT results alone. Of 200 seronegative donors evaluated

  18. Effect of Capreolus capreolus and Sus scrofa excreta on alanine aminotransferase activity in Glechoma hederacea leaves in conditions of Cd pollution

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    O. M. Vasilyuk

    2015-06-01

    Full Text Available The paper reflects the analysis of Cd impact on the total activity (nM pyruvic acid/ml s of alanine aminotransferase (ALT, EC 2.6.1.2 nitrogen metabolism and the content (mg/ml of water-soluble protein fraction (albumin in Glechoma hederacea L. leaves subject, which dominated in the research area (natural floodplain oak with Stellaria holostea L.. Cd was introduced in the form of salts Cd(NO32 in the concentrations of 0.25, 1.25 and 2.50 g/m2, equivalent to Cd in 1, 5 and 10 doses of MAC. The content of doses of MAC of Cd (5 mg/kg soil was taken into account during introduction. We observed the inhibition of the activity of ALT 3–4 times (with adding the Cd salts at a dose of 1 and 5 МAС compared to controls (area without pollution of Cd and excreta of mammals. This stress reaction took place in the protein complex as well. Thus, albumin content was equal to 72% and 80% (with Cd 1 and 5 MAC compared to control (the area without pollution and excretory functions of mammals. It proved nonspecific response to stress. Using excreta of Capreolus capreolus L. and Sus scrofa L. shows the reduction of Cd effects and increasing the metabolic activity of ALT by 41% and 105%, respectively (with adding of Cd 1 MAC compared to control (pollution by Cd at a dose 1 MAC. The effect of Cd 5 MAC is offset (only with the introduction of C. capreolus excreta compared to control (pollution by Cd at a dose 5 MAC. Normalization of the albumin content (with adding of Cd 1 and 5 MAC compared to control (сontrol of Cd at a dose 1 MAC and сontrol of Cd at a dose 5 MAC with using of excreta of C. capreolus was observed. In conditions of Cd at a doze 10 MAC the ALT activity was reduced 2 times with the introduction of excreta of C. capreolus as S. scrofa compared to control (Cd at a dose 10 MAC. The introduction of excreta of S. scrofa compared with C. capreolus restored the albumin content by 10% to the control. Thus, the feasibility of using different biological

  19. Performance of an Optimized Paper-Based Test for Rapid Visual Measurement of Alanine Aminotransferase (ALT in Fingerstick and Venipuncture Samples.

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    Sidhartha Jain

    Full Text Available A paper-based, multiplexed, microfluidic assay has been developed to visually measure alanine aminotransferase (ALT in a fingerstick sample, generating rapid, semi-quantitative results. Prior studies indicated a need for improved accuracy; the device was subsequently optimized using an FDA-approved automated platform (Abaxis Piccolo Xpress as a comparator. Here, we evaluated the performance of the optimized paper test for measurement of ALT in fingerstick blood and serum, as compared to Abaxis and Roche/Hitachi platforms. To evaluate feasibility of remote results interpretation, we also compared reading cell phone camera images of completed tests to reading the device in real time.96 ambulatory patients with varied baseline ALT concentration underwent fingerstick testing using the paper device; cell phone images of completed devices were taken and texted to a blinded off-site reader. Venipuncture serum was obtained from 93/96 participants for routine clinical testing (Roche/Hitachi; subsequently, 88/93 serum samples were captured and applied to paper and Abaxis platforms. Paper test and reference standard results were compared by Bland-Altman analysis.For serum, there was excellent agreement between paper test and Abaxis results, with negligible bias (+4.5 U/L. Abaxis results were systematically 8.6% lower than Roche/Hitachi results. ALT values in fingerstick samples tested on paper were systematically lower than values in paired serum tested on paper (bias -23.6 U/L or Abaxis (bias -18.4 U/L; a correction factor was developed for the paper device to match fingerstick blood to serum. Visual reads of cell phone images closely matched reads made in real time (bias +5.5 U/L.The paper ALT test is highly accurate for serum testing, matching the reference method against which it was optimized better than the reference methods matched each other. A systematic difference exists between ALT values in fingerstick and paired serum samples, and can be

  20. Alanine-glyoxylate aminotransferase 2 (AGXT2) polymorphisms have considerable impact on methylarginine and β-aminoisobutyrate metabolism in healthy volunteers.

    Science.gov (United States)

    Kittel, Anja; Müller, Fabian; König, Jörg; Mieth, Maren; Sticht, Heinrich; Zolk, Oliver; Kralj, Ana; Heinrich, Markus R; Fromm, Martin F; Maas, Renke

    2014-01-01

    Elevated plasma concentrations of asymmetric (ADMA) and symmetric (SDMA) dimethylarginine have repeatedly been linked to adverse clinical outcomes. Both methylarginines are substrates of alanine-glyoxylate aminotransferase 2 (AGXT2). It was the aim of the present study to simultaneously investigate the functional relevance and relative contributions of common AGXT2 single nucleotide polymorphisms (SNPs) to plasma and urinary concentrations of methylarginines as well as β-aminoisobutyrate (BAIB), a prototypic substrate of AGXT2. In a cohort of 400 healthy volunteers ADMA, SDMA and BAIB concentrations were determined in plasma and urine using HPLC-MS/MS and were related to the coding AGXT2 SNPs rs37369 (p.Val140Ile) and rs16899974 (p.Val498Leu). Volunteers heterozygous or homozygous for the AGXT2 SNP rs37369 had higher SDMA plasma concentrations by 5% and 20% (p = 0.002) as well as higher BAIB concentrations by 54% and 146%, respectively, in plasma and 237% and 1661%, respectively, in urine (both p<0.001). ADMA concentrations were not affected by both SNPs. A haplotype analysis revealed that the second investigated AGXT2 SNP rs16899974, which was not significantly linked to the other AGXT2 SNP, further aggravates the effect of rs37369 with respect to BAIB concentrations in plasma and urine. To investigate the impact of the amino acid exchange p.Val140Ile, we established human embryonic kidney cell lines stably overexpressing wild-type or mutant (p.Val140Ile) AGXT2 protein and assessed enzyme activity using BAIB and stable-isotope labeled [²H₆]-SDMA as substrate. In vitro, the amino acid exchange of the mutant protein resulted in a significantly lower enzyme activity compared to wild-type AGXT2 (p<0.05). In silico modeling of the SNPs indicated reduced enzyme stability and substrate binding. In conclusion, SNPs of AGXT2 affect plasma as well as urinary BAIB and SDMA concentrations linking methylarginine metabolism to the common genetic trait of hyper

  1. Alanine-glyoxylate aminotransferase 2 (AGXT2 polymorphisms have considerable impact on methylarginine and β-aminoisobutyrate metabolism in healthy volunteers.

    Directory of Open Access Journals (Sweden)

    Anja Kittel

    Full Text Available Elevated plasma concentrations of asymmetric (ADMA and symmetric (SDMA dimethylarginine have repeatedly been linked to adverse clinical outcomes. Both methylarginines are substrates of alanine-glyoxylate aminotransferase 2 (AGXT2. It was the aim of the present study to simultaneously investigate the functional relevance and relative contributions of common AGXT2 single nucleotide polymorphisms (SNPs to plasma and urinary concentrations of methylarginines as well as β-aminoisobutyrate (BAIB, a prototypic substrate of AGXT2. In a cohort of 400 healthy volunteers ADMA, SDMA and BAIB concentrations were determined in plasma and urine using HPLC-MS/MS and were related to the coding AGXT2 SNPs rs37369 (p.Val140Ile and rs16899974 (p.Val498Leu. Volunteers heterozygous or homozygous for the AGXT2 SNP rs37369 had higher SDMA plasma concentrations by 5% and 20% (p = 0.002 as well as higher BAIB concentrations by 54% and 146%, respectively, in plasma and 237% and 1661%, respectively, in urine (both p<0.001. ADMA concentrations were not affected by both SNPs. A haplotype analysis revealed that the second investigated AGXT2 SNP rs16899974, which was not significantly linked to the other AGXT2 SNP, further aggravates the effect of rs37369 with respect to BAIB concentrations in plasma and urine. To investigate the impact of the amino acid exchange p.Val140Ile, we established human embryonic kidney cell lines stably overexpressing wild-type or mutant (p.Val140Ile AGXT2 protein and assessed enzyme activity using BAIB and stable-isotope labeled [²H₆]-SDMA as substrate. In vitro, the amino acid exchange of the mutant protein resulted in a significantly lower enzyme activity compared to wild-type AGXT2 (p<0.05. In silico modeling of the SNPs indicated reduced enzyme stability and substrate binding. In conclusion, SNPs of AGXT2 affect plasma as well as urinary BAIB and SDMA concentrations linking methylarginine metabolism to the common genetic trait of hyper

  2. Non-alcoholic steatohepatitis with normal aminotransferase values

    Institute of Scientific and Technical Information of China (English)

    H(u)eyin Saadettin Uslusoy; Selim Giray Nak; Macit G(u)lten; Zeynep Biyikli

    2009-01-01

    AIM: To investigate the aspects of liver histology in patients with non-alcoholic steatohepatitis (NASH) who had normal aminotransferase levels. METHODS: Thirty-four patients diagnosed with liver steatosis by ultrasonographic examination participated in the study. We compared all nonalcoholic fatty liver disease and NASH cases, according to aminotransferase level, aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio and presence of metabolic syndrome. RESULTS: Si x t e en of 25 pa t i ent s wi th high aminotransferase levels were diagnosed with NASH and nine with simple fatty liver according to liver histology. Among the nine patients with normal aminotransferase levels, seven had NASH and two had simple fatty liver. The patients with normal and high liver enzyme levels had almost the same prevalence of NASH and metabolic syndrome. Liver histology did not reveal any difference according to aminotransferase levels and AST/ALT ratio. CONCLUSION: Aminotransferase levels and AST/ALT ratio do not seem to be reliable predictors for NASH. Despite numerous non-invasive biomarkers, all patients with fatty liver should undergo liver biopsy.

  3. Studies on the influence of combustion exhaust gases and the products of their reaction with ammonia on the living organism. II. The influence on aspartate aminotransferase (AspAT) and alanine aminotransferase (AiAt) activities in the liver of guinea pig

    Energy Technology Data Exchange (ETDEWEB)

    Lewandowska-Tokarz, A.; Stanosek, J.; Ludyga, K.; Kochanski, L.

    1981-01-01

    The behaviour of aspartate aminotransferase (AspAT) an alanine aminotransferase (AIAT) in the whole homogenate and subcellular liver fractions of guinea pigs exposed to combustion exhaust gases and the neutralization products of these gases is presented in this paper. In the liver of animals exposed to the chronic action of combustion exhaust gases a decrease of both enzyme activities in the whole homogenate as well as in the subcellular fractions could be noted. Statistically significant changes are shown by AspAT. In the group of animals subjected to the action of neutralization products an increase of AIAT activity was observed. The activity of AspAT still shows a decrease, but less distinct in comparison with group I.

  4. Studies on the influence of combustion exhaust gases and the products of their reaction with ammonia on the living organism. II. The influence on aspartate aminotransferase (AspAT) and alanine aminotransferase (AiAt) activities in the liver of guinea pig.

    Science.gov (United States)

    Lewandowska-Tokarz, A; Stanosek, J; Ludyga, K; Kochanski, L

    1981-01-01

    The behaviour of aspartate aminotransferase (AspAT) an alanine aminotransferase (AIAT) in the whole homogenate and subcellular liver fractions of guinea pigs exposed to combustion exhaust gases and the neutralization products of these gases is presented in this paper. In the liver of animals exposed to the chronic action of combustion exhaust gases a decrease of both enzyme activities in the whole homogenate as well as in the subcellular fractions could be noted. Statistically significant changes are shown by AspAT. In the group of animals subjected to the action of neutralization products an increase of AIAT activity was observed. The activity of AspAT still shows a decrease, but less distinct in comparison with group I. An exception here is the mitochondrial fraction in which the AspAT activity is distinctly increased.

  5. Etiological analysis of college freshmen with elevated alanine aminotransferase%某高校新生丙氨酸氨基转移酶升高病因分析

    Institute of Scientific and Technical Information of China (English)

    康荣芹; 朱立新

    2015-01-01

    目的:探讨某高校新生ALT升高原因。方法选取某高校2010年至2014年297例ALT升高者新生为观察组,随机抽取200例同期体检ALT正常新生为对照组,比较两组脂肪肝及超重或肥胖发病率,并进行统计学分析。结果 ALT升高新生中脂肪肝、肥胖发病率明显高于对照组(P =0.000)。结论肥胖引发的脂肪肝是引起高校新生ALT升高的主要原因。%Objective To investigate the reasons of elevated alanine aminotransferase in college freshmen. Methods Total of 494 freshmen admitted from 2010 to 2014 were enrolled and divided into two groups, elevated alanine aminotransferase (ALT) group (297 cases) and normal ALT group (200 cases). The incidence of fatty liver, overweight and obesity rate were analyzed between the two groups. Results The freshmen with elevated ALT exhibited a significant increase in the incidence of fatty liver and obesity when compared to the freshmen with normal ALT. Conclusions Fatty liver induced by obesity may be the main cause of elevated ALT in the college freshmen.

  6. IFCC primary reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 degrees C. International Federation of Clinical Chemistry and Laboratory Medicine. Part 4. Reference procedure for the measurement of catalytic concentration of alanine aminotransferase.

    Science.gov (United States)

    Schumann, Gerhard; Bonora, Roberto; Ceriotti, Ferruccio; Férard, Georges; Ferrero, Carlo A; Franck, Paul F H; Gella, F Javier; Hoelzel, Wieland; Jørgensen, Poul Jørgen; Kanno, Takashi; Kessner, Art; Klauke, Rainer; Kristiansen, Nina; Lessinger, Jean-Marc; Linsinger, Thomas P J; Misaki, Hideo; Panteghini, Mauro; Pauwels, Jean; Schiele, Françoise; Schimmel, Heinz G; Weidemann, Gerhard; Siekmann, Lothar

    2002-07-01

    This paper is the fourth in a series dealing with reference procedures for the measurement of catalytic activity concentrations of enzymes at 37 degrees C and the certification of reference preparations. Other parts deal with: Part 1. The Concept of Reference Procedures for the Measurement of Catalytic Activity Concentrations of Enzymes; Part 2. Reference Procedure for the Measurement of Catalytic Concentration of Creatine Kinase; Part 3. Reference Procedure for the Measurement of Catalytic Concentration of Lactate Dehydrogenase; Part 5. Reference Procedure for the Measurement of Catalytic Concentration of Aspartate Aminotransferase; Part 6. Reference Procedure for the Measurement of Catalytic Concentration of Gamma-Glutamyltransferase; Part 7. Certification of Four Reference Materials for the Determination of Enzymatic Activity of Gamma-Glutamyltransferase, Lactate Dehydrogenase, Alanine Aminotransferase and Creatine Kinase at 37 degrees C. A document describing the determination of preliminary upper reference limits is also in preparation. The procedure described here is deduced from the previously described 30 degrees C IFCC reference method. Differences are tabulated and commented on in Appendix 2.

  7. Aspartate aminotransferase-to-platelet ratio index for fibrosis and cirrhosis prediction in chronic hepatitis C patients

    Directory of Open Access Journals (Sweden)

    Roberto Gomes da Silva Junior

    2008-02-01

    Full Text Available In chronic hepatitis C (CHC, liver biopsy is the gold standard method for assessing liver histology, however it is invasive and can have complications. Non-invasive markers have been proposed and aspartate aminotransferase (AST-to-platelet ratio index (APRI has been shown as an easy and inexpensive marker of liver fibrosis. This study evaluated the diagnostic performance of APRI for significant fibrosis and cirrhosis prediction in CHC patients. This study included treatment-naive CHC patients who had undergone liver biopsy from January 2000 to August 2006. All histological slides were reviewed according to the METAVIR system. APRI was calculated based on laboratory results performed within four months from the biopsy. Twenty-eight (56% patients had significant fibrosis (F2-F4 and 13 (26% had cirrhosis (F4. The area under ROC curves of APRI for predicting significant fibrosis and cirrhosis were 0.92 (0.83-1.00 and 0.92 (0.85-1.00, respectively. Using cut-off values recommended by prior studies, significant fibrosis could be identified, in accordance with liver biopsy, in 44% and cirrhosis in 66% of patients. APRI could identify significant fibrosis and cirrhosis at a high degree of accuracy in studied patients.

  8. AMINOTRANSFERASE ACTIVITY IN THE LIVER OF RAINBOW TROUT (ONCORHYNCHUS MYKISS UNDER VIRAL INFECTION

    Directory of Open Access Journals (Sweden)

    L. Dragan

    2015-10-01

    Full Text Available Purpose. To study the effect of the use of indirect (express- method for the detection of infectious pancreatic necrosis virus of trout by investigating aspartate aminotransferase and alanine aminotransferase activities in fish liver, as the most sensitive enzymes for the diagnostics of many pathological conditions of human and animal organisms associated with liver diseases. Methodology. The determination of aspartate aminotransferase and alanine aminotransferase activities in trout liver was performed by Reitman-Frankel method. The functional status of liver was also evaluated using De Ritis coefficient (AST/ALT ratio, which serves as an integral index of the changes related to the degree of the damage of this organ. Findings. The determination of aspartate aminotransferase and alanine aminotransferase activities in the liver of rainbow trout (Oncorhynchus mykiss found out a considerable increase in the activity of these enzymes under the effect of the virus of infectious pancreatic necrosis. It is set that direction of aspartate aminotransferase reactions in the conditions of viral infection takes place mainly in the side of formation of keto-acids, providing the synthesis of glucose which is needed above all things for energetic supply of synthetic processes. The increase of activity of AsAT plays an important role in synchronization of energetic and nitrous exchange which is carried out at the level of mitochondrias. Increase of DeRitisa (DRr coefficient in the conditions of our experiment characteristic for viral hepatitis and can specify on activating of synthesis of glucose which is needed for support of adequate level in the conditions of viral intoxication and determines the orientation of metabolic streams toward predominance of catabolytic reactions. According to the results of the performed tests, the most informative was the test of the determination of alanine aminotransferase activity. Originality. Evaluation of the effect of

  9. Noninvasive assessment of liver fibrosis with combined serum aminotransferase/platelet ratio index and hyaluronic acid in patients with chronic hepatitis B

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    AIM: To construct a noninvasive assessment model consisting of routine laboratory data to predict significant fibrosis and cirrhosis in patients with chronic hepatitis B (CHB). METHODS: A total of 137 consecutive patients with CHB who underwent percutaneous liver biopsy were retrospectively analyzed. These patients were divided into two groups according to their aminotransferase (ALl-) level. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), the likelihood ratio (LR) of aminotransferase/platelet ratio index (APRI) ≥ 1.5 or 300 ng/mL could detect moderate to severe fibrosis (stages 2-4) in CHB patients. The PPV was 93.7%, the specificity was 98.9%. The APRI 300 ng/mL can detect moderate to severe fibrosis (stages 2-4) in CHB patients.

  10. Levamlodipine Besylate Induced Elevated Alanine Aminotransferase:Report of 1 Cases%1例苯磺酸左旋氨氯地平致谷丙转氨酶升高报告

    Institute of Scientific and Technical Information of China (English)

    王惠英; 张志辉; 康岩; 时新超

    2015-01-01

    Levamlodipine besylate two dihydropyridine calcium antagonist, is a kind of high curative ef ect, high safety, high compliance, less adverse reaction of the ideal anti hypertension drugs, can be used as the first choice of antihypertensive drugs. But considering the many old people have the function of liver and kidney and heart dysfunction, and associated with other diseases and cor esponding drug treatment, general lower bounds using initial drug dose range. Prevent elevated alanine aminotransferase.%苯磺酸左旋氨氯地平是二氢吡啶类钙拮抗剂,是一种疗效高,安全性高,依从性高,不良反应少的理想抗高血压药物,可以作为抗高血压的首选药物。但考虑到老年人多有肝肾功能和心功能减退,并伴有其它疾病和相应的药物治疗,一般起始用药采用剂量范围的下限。防止谷丙转氨酶升高。

  11. Purification and characterization of cysteine aminotransferase from rat liver cytosol.

    Directory of Open Access Journals (Sweden)

    Akagi,Reiko

    1982-06-01

    Full Text Available Cysteine aminotransferase (L-cysteine: 2-oxoglutarate aminotransferase, EC 2.6.1.3 was purified over 400-fold from the high-speed supernatant fraction of rat liver. The purified enzyme was homogeneous as judged by gel filtration, isoelectric focusing and disc electrophoresis. The molecular weight of the enzyme was about 74,000 by gel filtration and the isoelectric point was 6.2 (4 degrees C. The enzyme catalyzed transamination between L-cysteine and 2-oxoglutarate and the reverse reaction. The optimum pH was 9.7. The Km value for L-cysteine was 22.2 mM, and that for 2-oxoglutaric acid was 0.06 mM. L-Aspartate was a potent inhibitor of the cysteine aminotransferase reaction. The enzyme was very active toward L-alanine 3-sulfinic acid at pH 8.0, and was also very active toward L-aspartic acid (Km = 1.6 mM. Ratios of activities for L-aspartic acid and L-cysteine were essentially constant during the purification of the enzyme. Evidence based on substrate specificity, enzyme inhibition, and physicochemical properties indicates that cytosolic cysteine aminotransferase is identical with cytosolic aspartate aminotransferase (L-aspartate: 2-oxoglutarate aminotransferase, EC 2.6.1.1.

  12. Correlations of serum alanine aminotransferase and insulin resistance, pancreatic B-cell function%丙氨酸转氨酶水平与胰岛素抵抗及胰岛β细胞功能的关系

    Institute of Scientific and Technical Information of China (English)

    王永慧; 黎明; 高珊; 张秀娟; 李连霞; 张葵

    2011-01-01

    Objective To explore the correlations of serum alanine aminotransferase (ALT),insulin resistance and pancreatic B-cell function.Methods A total of 351 first-degree relatives of type 2 diabetes mellitus received a standard oral glucose tolerance test (OGTT) at our outpatient clinic.All subjects were analyzed for the parameters of body mass index ( BMI),waist-hip ratio,blood pressure ( BP),serum lipids,ALT,aspartate aminotransferase (AST),plasma glucose (PG),true-insulin and proinsulin.Homeostasis model assessment (HOMA) was applied to assess the status of insulin resistance and pancreatic B-cell function. They were divided into 4 groups according to the quartiles of ALT:ALT1 group (<12.9 U/L),ALT2 group (12.9- 17.3 U/L),ALT3 group (17.4-24.2 U/L) and ALT4 group ( ≥24.2 U/L).The diagnosis of metabolic syndrome was made according to the definition of Chinese Diabetic Society.Results With the rising serum ALT levels (ALT4 vs ALT1 ),the levels of BMI [ (26.3 ± 2.9) kg/m2 vs (23.2±3.7) kg/m2,P<0.01],HOMA-IR [1.93(1.21 -3.26) vs 1.06(0.65 -1.54),P<0.01] and LnHOMA-beta (2.00 ±0.32 vs 1.87 ±0.28,P<0.05) were elevated; BP,serum lipids,PG,true-insulin and proinsulin also increased ( P < 0.05 or P < 0.01 ).The levels of serum ALT [ 23.3(16.3-37.6) vs 14.3 (10.3-18.5) U/L,P<0.01] and AST [21.5 (18.3-32.8) U/L vs 17.9( 15.5 -22.1 ) U/L,P <0.01 ] increased with the rising number of metabolic disorders (0 vs 3 -4 metabolic disorders).After adjustments for gender,age,BMI and waist-hip ratio,serum ALT were still positively correlated with BP,serum lipids,PG,fasting true-insulin,2 h proinsulin,2 h proinsulin/true-insulin,HOMA-IR and the numbers of metabolic disorder (r=0.117 -0.236,P<0.05 or P<0.01).After adjustments for gender,age,BMI,waist-hip ratio and HOMA-IR,the serum ALT level remained positively correlated with the numbers of metabolic disorders (r =0.120,P < 0.05).Multiple stepwise regression analysis showed that triglyceride

  13. Development of dry chemistry method for alanine aminotransferase%丙氨酸氨基转移酶干化学检测方法的建立及试纸条的制备

    Institute of Scientific and Technical Information of China (English)

    田漪; 陈汉艳; 王缦

    2012-01-01

    Objective To develop a dry chemistry method for alanine aminotransferase (ALT) based on pyruvate oxidase method and prepare the test strip. Methods The test strip consisted of a sample spreading layer,a substrate layer and a color de-velopment layer,which was coated with reaction agent for determination of ALT activity by reflectance photometer. The prepared test strip was verified. Results The intra-CV of the test strip for low (48. 7 U/L) and high (127 U/L) level quality controls were 7. 4% and 4. 9% respectively. The linear range of the test strip was 10 ~ 1 000 U/L No significant difference was observed between the determination results of heparinized blood and plasma by the test strip (P > 0. 05). The determination results of ALT were uninfluenced when the bilirubin content in sample was not more than 257 μmol / L,the ascorbic acid content was not more than 50 mg / L,and the pyruvate content was not more than 0. 5 mmol / L. The developed dry chemistry method showed good relationship to the method recommended by International Federation of Clinical Chemistry (IFCC)(r = 0. 988 9). The reference range of 95% confidence interval of the test strip was 0 ~ 40 U / L. Conclusion The developed dry chemistry method was rapid,accurate and simple,which was suitable for immediate determination of ALT.%目的 建立一种以丙酮酸氧化酶法为反应原理的丙氨酸氨基转移酶( Alanine aminotransferase,ALT)干化学检测方法,并制备试纸条.方法 试纸条由扩散层、底物层和显色层组成,包被有反应试剂,用反射式光度计测定ALT活性.对制备的试纸条进行各项验证.结果 试纸条测定罗氏低、高值质控品的批内变异系数分别为7.4%和4.9%;线性范围为10~1000U/L;试纸条测定肝素锂抗凝全血及其血浆的结果差异无统计学意义(P>0.05);标本中胆红素≤257 mol/L,抗坏血酸≤50 mg/L,丙酮酸≤0.5 mmol/L时,ALT测定结果不受影响;建立的干化学法与国际临床化学

  14. Lingmao Formula Combined with Entecavir for HBeAg-Positive Chronic Hepatitis B Patients with Mildly Elevated Alanine Aminotransferase: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

    Directory of Open Access Journals (Sweden)

    Xiao-Jun Zhu

    2013-01-01

    Full Text Available Objective. To determine the efficacy and safety of Lingmao Formula combined with entecavir for HBeAg-positive chronic hepatitis B patients with mildly elevated alanine aminotransferase (ALT. Methods. 301 patients were randomly assigned to receive Lingmao Formula combined with entecavir (treatment group or placebo combined with entecavir (control group for 52 weeks. The outcomes of interest included the reduction of serum HBV DNA level, HBeAg loss, HBeAg seroconversion, ALT normalization, and histological improvement. Results. The mean decrease of serum HBV DNA level from baseline and the percentage of patients who had reduction in serum HBV DNA level ≥2 lg copies/mL in treatment group were significantly greater than that in control group (5.5 versus 5.4 lg copies/mL, P=0.010; 98.5% versus 92.6%, P=0.019. The percentage of HBeAg loss in treatment group was 22.8%, which was much higher than a percentage of 12.6% in control group (P=0.038. There was no significant difference between the two groups in histological improvement. Safety was similar in the two groups. Conclusions. The combination of Lingmao Formula with entecavir could result in significant decrease of serum HBV DNA and increase of HBeAg loss for HBeAg-positive chronic hepatitis B patients with mildly elevated ALT without any serious adverse events. Clinical trial registration number is ChiCTR-TRC-09000594.

  15. Evolution of alanine:glyoxylate aminotransferase 1 peroxisomal and mitochondrial targeting. A survey of its subcellular distribution in the livers of various representatives of the classes Mammalia, Aves and Amphibia.

    Science.gov (United States)

    Danpure, C J; Fryer, P; Jennings, P R; Allsop, J; Griffiths, S; Cunningham, A

    1994-08-01

    As part of a wider study on the molecular evolution of alanine:glyoxylate aminotransferase 1 (AGT1) intracellular compartmentalization, we have determined the subcellular distribution of immunoreactive AGT1, using postembedding protein A-gold immunoelectron microscopy, in the livers of various members of the classes Mammalia, Aves, and Amphibia. As far as organellar distribution is concerned, three categories could be distinguished. In members of the first category (type I), all, or nearly all, of the immunoreactive AGT1 was concentrated within the peroxisomes. In the second category (type II), AGT1 was found more evenly distributed in both peroxisomes and mitochondria. In the third category (type III), AGT1 was localized mainly within the mitochondria with much lower, but widely variable, amounts in the peroxisomes. Type I animals include the human, two great apes (gorilla, orangutan), two Old World monkeys (anubis baboon, Japanese macaque), a New World monkey (white-faced Saki monkey), a lago, morph (European rabbit), a bat (Seba's short-tailed fruit bat), two caviomorph rodents (guinea pig, orange-rumped agouti), and two Australian marsupials (koala, Bennett's wallaby). Type II animals include two New World monkeys (common marmoset, cotton-top tamarin), three prosimians (brown lemur, fat-tailed dwarf lemur, pygmy slow loris), five rodents (a hybrid crested porcupine, Colombian ground squirrel, laboratory rat, laboratory mouse, golden hamster), an American marsupial (grey short-tailed opossum), and a bird (raven). Type III animals include the large tree shrew, three insectivores (common Eurasian mole, European hedgehog, house shrew), four carnivores (domestic cat, ocelot, domestic dog, polecat ferret), and an amphibian (common frog). In addition to these categories, some animals (e.g. guinea pig, common frog) possessed significant amounts of cytosolic AGT1. Whereas the subcellular distribution of AGT1 in some orders (e.g. Insectivora and Carnivora) did not appear

  16. Association of response to combined interferon alpha-2b and ribavirin therapy in patients of chronic hepatitis C with serum alanine aminotransferase levels and severity of the disease on liver biopsy

    International Nuclear Information System (INIS)

    Raised serum alanine aminotransferase (serum ALT) levels indicate active liver disease while liver biopsy has been considered the 'gold standard' for assessing the severity of disease in patients of chronic Hepatitis C. The response of these patients to standard treatment regimen of interferon (INF)-alpha- 2b and ribavirin for 24 weeks have been studied. The objective of this study was to evaluate the association of response to combined INF alpha-2b and ribavirin therapy in patients of chronic hepatitis C with serum ALT levels and severity of the disease on liver biopsy. This quasi experimental study was conducted in Department of Physiology at Army Medical College and Military Hospital, Rawalpindi from January 2006 to February 2007. One hundred and even diagnosed non cirrhotic chronic hepatitis C patients were studied. Prior to the commencement of treatment, qualitative assay of Hepatitis C Virus (HCV) Ribonucleic Acid (RNA) was done by Polymerase chain reaction (PCR). Knodell Histopathological Index (HPI) was determined on liver biopsy. The standard treatment of INF-alpha-2b, 3 million units 3 times a week subcutaneous, and Ribavirin 800-1200 mg per day was given for 24 weeks. Serum ALT levels were determined before the start of treatment and later at weeks 12 and 24. Qualitative assay of HCV RNA was done by PCR at the end of treatment to determine the response to treatment. Statistical analysis was done on SPSS 15. Out of 107 patients of chronic hepatitis C, 92 (69 males, 23 females) patients (84%) responded to INF-alpha-2b and ribavirin therapy and revealed negative qualitative assay of HCV RNA by PCR at the end of 24 weeks of treatment while serum ALT levels were normal in 88% of patients at 12 weeks and in 97% at the end of 24 weeks of treatment. Knodell HPI revealed mild, moderate and severe disease in 47.7%, 39.9% and 13.1% of patients respectively. No association was established between response to treatment and severity of the disease on liver biopsy (p<0

  17. 肝脏丙氨酸氨基转移酶活性变化与生活习惯的相关性%CORRELATION OF LIVER ALANINE AMINOTRANSFERASE WITH LIFESTYLE HABITS

    Institute of Scientific and Technical Information of China (English)

    武丽芬; 赵海燕; 王响

    2014-01-01

    目的:探讨丙氨酸氨基转移酶(ALT )活性与生活习惯的联系,保证优良的生活质量。方法对10280例体检者进行身高、体重、饮酒、吸烟、饮食、运动、熬夜、服用药物等各种影响因素的实地调查,数据进行Epidata3.0双录入,导入SPSS 13.0进行统计分析;单因素分析采用χ2检验,多因素分析采用非条件Logistic回归分析。结果异常率为9.76%,ALT升高标本有1003例,体重质量指数、饮酒、运动及体力劳动、熬夜、服用药物是ALT升高的影响因素;清淡饮食是ALT升高的保护因素;吸烟对ALT的影响不大。单因素分析与多因素Logistic回归分析结果基本一致。结论本研究对人们养成良好的生活习惯有积极的指导意义,提醒人们健康的体质来源于良好的生活习惯。%Objective To explore the relationship of liver alanine aminotransferase (ALT ) with lifestyle habits for promising the best life quality .Methods A questionnaire was established ,the relative factors of 10280 subjects were surveyed included height ,weight ,drinking ,smoking ,diet ,exercise ,stay up late , taking drugs ,et al .The database was established by Epidata 3 .0 and SPSS 13 .0 package was used statistic analysis .Results Among 10280 subjects ,the ALT level of 1003 samples were increased ,and the abnor-mal rate reached to 9 .76 percent .The results showed that BMI ,alcohol consumption ,exercise and physi-cal labor ,stay up late and taking drugs were risk factors ;Light diet was a protection factor;but smoking was almost no impact on ALT .Conclusion The research results remind people the healthy constitution come from the good life styles .

  18. Application of reference method in the standardization for the determination of alanine aminotransferase%参考方法在丙氨酸氨基转移酶测定标准化中的应用

    Institute of Scientific and Technical Information of China (English)

    郑松柏; 王建兵; 黄宪章; 马艳; 庄俊华; 徐宁; 周华友; 陈茶

    2012-01-01

    Objective To investigate the accuracy and comparability of alanine aminotransferase(ALT) measurement results in human serum samples and commercial materials before and after calibration with frozen human serum calibrator assigned by reference method. Methods Five frozen human-pooled serum samples were assigned values by the reference method without pyridoxal 5-phosphate for ALT in four candidate reference laboratories, which were used to evaluate the results of ALT catalytic activity detected by ten testing systems in Guangzhou. One of the serum sample was used as the common calibrator. The results of serum samples and commercial materials from different systems before and after calibration were analyzed for biases and intersystem variations. Results After calibration,the variance of the systems for the results of serum samples decreased from between 11. 90% and 8. 60% to between 6. 78% and 2. 30% ,and the bias decreased dramatically from between - 12. 52% and - 8. 44 % to between - 3. 36% and -0. 08%. Slopes of the regression lines of ALT results of serum samples between reference systems and routine systems after calibration were closer to 1 and intercepts closer to 0 than those obtained before calibration. Conclusion Accuracy and comparability of ALT measurements could be improved by using a common human serum calibrator. But commercial materials might not be commutable for human serum in ALT measurements.%目的 调查不同检测系统使用经参考方法赋值的冰冻人血清样本作为校准品进行校准后,不同来源样本丙氨酸氨基转移酶(ALT)测定结果的可比性与准确性的改变程度.方法 5份经4家候选参考实验室应用不含磷酸吡哆醛的ALT参考方法定值的冰冻人混合血清样本用于评价广州地区10个不同检测系统ALT催化活性结果的可比性与准确性.其中一个样本用作校准品校准各系统.比较校准前后各系统间新鲜血清样本与商品制备物测定

  19. 血清谷丙转氨酶与儿童超重、肥胖的关系%Relationship between alanine aminotransferase and overweight or obesity in children

    Institute of Scientific and Technical Information of China (English)

    范歆; 陈少科; 唐晴; 罗静思; 冯莹

    2011-01-01

    目的 探讨血清谷丙转氨酶(ALT)与儿童超重、肥胖的关系.方法 对年龄7~18岁的2889例正常儿童及702例超重、肥胖儿童的资料进行分析,测量身高、体重、腰围、血压,检测空腹血糖、血脂、ALT、胰岛素等生化指标,计算胰岛素抵抗指数.结果 男童ALT水平高于女童.随着体重指数(BMI)的增加,男女童正常组、超重组、肥胖组ALT水平均逐渐增加.ALT与BMI、腰围、甘油三酯、胰岛素抵抗指数等相关.在超重、肥胖儿童中,男童ALT升高组BMI、腰围、血压、甘油三酯、低密度脂蛋白、胰岛素抵抗指数均较ALT正常组高(P<0.05);女童ALT升高组腰围、血压、胰岛素抵抗指数高于ALT正常组,而高密度脂蛋白降低(P<0.05).结论 ALT与儿童超重、肥胖及其引起代谢异常如血脂异常、胰岛素抵抗相关.%Objective To study the association of alanine aminotransferase ( ALT) with overweight or obesity in children. Methods A total of 2889 healthy children and 702 overweight or obese children aged from 7 to 18 years who had received a physical examination were enrolled. Height, body weight, waist circumference, and blood pressure were measured, and the biochemical indicators including blood glucose, blood lipids, ALT, and insulin were detected. The insulin resistance index were calculated. Results The ALT level was significantly higher in boys than in girls. Along with the increase of BMI, the ALT level increased in the normal, overweight, and obese groups in both boys and girls. ALT was correlated with BMI, waist circumference, triglyceride, and insulin resistance index. Among the overweight or obese children, the boys with the increased ALT level had higher BMI, waist circumference, blood pressure, triglyceride, low density lipoprotein and insulin resistance index than the boys with normal ALT level (P < 0. 05 ) ; the girls with the increased ALT level had higher waist circumference, blood pressure and

  20. Association between Serum Alanine Aminotransferase Level and Coronary Heart Disease%血清丙氨酸氨基转移酶水平与冠心病的相关性研究

    Institute of Scientific and Technical Information of China (English)

    余慧珍; 杨万松

    2013-01-01

    Objective To study the relationship between the serum alanine aminotransferase ( ALT ) level and coronary heart disease ( CHD ). Methods A total of 426 inpatients from the Second Hospital of Tianjin Medical University in 2011 were enrolled in this study and their serum ALT levels were determined and the coronary artery angiography was performed. Based on the results of coronary artery angiography, these patients were divided in the CHD group ( n = 294 ) and control group ( n = 132 ). The CHD group was further divided into three subgroups: single - branch subgroup ( n = 89 ), double - branch subgroup ( n = 91 ), and multiple - branch subgroup ( n = 114 ). The levels of serum ALT were compared among these groups. Results The serum ALT level was significantly higher in the CHD group than in the control group [ ( 23. 4 ± 18. 7 ) U/L vs. ( 17. 8 ± 13.2) U/L, P < 0. 01 ]. The three subgroups also showed significantly different ALT level when compared with the control group ( F = 5. 137, P =0. 002 ). Multivariate Logistic regression analysis showed the higher serum ALT level was associated with the occurrence of CHD [ 0R= 0.966, 95%CI (0.944, 0.988), P<0.0l]. Conclusion CHD patients have higher serum ALT level than non - CHD patients. Serum ALT level can be used for predicting the severity of CHD.%目的 探讨血清丙氨酸氨基转移酶(ALT)与冠心病(CHD)的关系.方法 选择2011年在天津医科大学第二医院心脏科住院的426例患者,均检测血清ALT水平,并行冠状动脉造影评价冠状动脉病变程度.根据冠状动脉造影结果分为冠心病组(294例)和对照组(132例).冠心病组再根据病变支数分为单支病变组(89例)、双支病变组(91例)和多支病变组(114例);分析血清ALT水平与冠状动脉病变严重程度的相关性.结果 冠心病组血清ALT水平明显高于对照组,差异有统计学意义[(23.4±18.7)U/L和(17.8±13.2)U/L,P<0.01];冠心病3个亚组及对照组ALT水平

  1. 丙氨酸转氨酶升高患者代谢异常情况及危险因素分析%Combined dysmetabolism and risk factors of elevated serum alanine aminotransferase

    Institute of Scientific and Technical Information of China (English)

    刘安楠; 朱玲; 赵艳燕; 宋悦华; 高建萍

    2010-01-01

    Objective To investigate the prevalence of elevated serum alanine aminotransferase ( ALT) and ALT-related dysmetabolism and risk factors. Methods A total of 12 789 adult participated,with no hepatitis B virus infection or alcohol over-intake, received health check-up, including blood pressure measurement, blood glucose and lipid profile test, liver function evaluation and ultrasonography. The subjects were then assigned into two groups according to the serum level of ALT. Metabolic composition was compared between the two groups. Results The prevalence of elevated ALT activity was 8.69%. The waist circumstance,body mass index (BMI) ,systolic blood pressure (SBP) ,diastolic blood pressure (DBP) ,total cholesterol (TC) ,triglyceride (TG) , low-density lipoprotein cholesterol (LDL-C) , urine acid (UA) , fasting blood glucose (FBG) ,HbAlc,total bilirubin (TBIL) ,-y-glutamyltransferase (GGT) ,alkaline phos-phatase ( ALP) of the elevated ALT group were significantly higher than those of the normal ALT group. However,age and high-density lipoprotein cholesterol ( HDL-C) in the elevated ALT group were lower than those in the normal ALT group ( P 40 U/L)分为两组,比较两组间各代谢组分的差异.结果 ALT升高的检出率为8.69%.ALT升高组的腰围、体质指数、收缩压、舒张压、总胆固醇、三酰甘油、低密度脂蛋白胆固醇、尿酸、空腹血糖、血红蛋白、总胆红素、谷氨酰转移酶、碱性磷酸酶水平均高于ALT正常组,而年龄、高密度脂蛋白胆固醇(HDL-C)水平低于ALT正常组(P<0.05).ALT升高组超重、肥胖、各型高脂血症、空腹血糖受损、糖尿病、舒张压高、高尿酸血症、脂肪肝检出率高于ALT正常组(P<0.05).logistic回归分析显示:患脂肪肝、舒张压、体质指数、总胆固醇、血红蛋白是ALT升高的危险因素,年龄、HDL-C是保护因素.结论 非酒精性脂肪性肝病、脂代谢紊乱、肥胖是丙氨酸转氨酶升高的重要危险因素.

  2. 茶树丙氨酸氨基转移酶基因的克隆与表达分析%Cloning and Expression Analysis of Alanine Aminotransferase Gene in Camellia sinensis

    Institute of Scientific and Technical Information of China (English)

    白培贤; 王丽鸳; 韦康; 阮丽; 成浩; 张芬; 张成才

    2016-01-01

    丙氨酸氨基转移酶(Alanine Aminotransferase,AlaAT)是与碳氮代谢相关的一种重要酶类。采用反转录PCR 的方法克隆了茶树 CsAlaAT1的 cDNA 序列,该序列全长1747 bp,包含一个完整的 ORF(1626 bp),编码541个氨基酸,推导的蛋白质分子量为59.4 kD,理论等电点(pI)为5.82。同源比对结果表明,CsAlaAT1含有丙氨酸氨基转移酶亚家族保守的辅酶磷酸吡哆醛结合位点,其氨基酸序列与拟南芥 AtAlaAT1蛋白的相似性为84%。二级结构预测显示该蛋白由α-螺旋(40.67%)、无规则卷曲(29.57%)、β-折叠(13.68%)和延伸链(16.08%)组成,定位于线粒体,不含信号肽与跨膜结构。实时荧光定量 PCR(RT-PCR)检测发现 CsAlaAT1在茶树各组织中均有表达,在根中的表达量最高;CsAlaAT1基因表达对氮素的响应研究表明,成熟叶中CsAlaAT1受氮素诱导上调表达,高浓度(1 mmol·L-1 NH4NO3)氮素的诱导效应比低浓度(0.1 mmol·L-1 NH4NO3)氮素诱导效应更强烈;在根中,处理24 h 后,高氮诱导 CsAlaAT1上调表达,低氮诱导 CsAlaAT1下调表达。%Alanine Aminotransferase (AlaAT) is a critical enzyme involved in carbohydrate and nitrogen metabolisms. In this study, a cDNA (1 747 bp) with a complete ORF (1 626 bp) of AlaAT1 was isolated from tea plant (Camellia sinensis). The cDNA encodes a protein with 541 amino acids, which has a molecular mass of 59.4 kD and a theoretical isoelectric point (pI) of 5.82. The deduced sequence of protein CsAlaAT1 shared 84% similarity with AlaAT1 in Arabidopsis thaliana, which contains a highly-conserved pyridoxal 5′-phosphate binding site. Secondary structure prediction showed that the CsAlaAT1 was comprised of alpha helix (40.67%), random coil (29.57%), beta turn (13.68%) and extended strand (16.08%), localized in mitochondrion and had no signal peptide or transmembrane structure. The expression levels of CsAlaAT1 in

  3. Antiretroviral Drugs and Risk of Chronic Alanine Aminotransferase Elevation in Human Immunodeficiency Virus (HIV)-Monoinfected Persons: The Data Collection on Adverse Events of Anti-HIV Drugs Study

    OpenAIRE

    Kovari, Helen; Sabin, Caroline A.; Ledergerber, Bruno; Ryom, Lene; Reiss, Peter; Law, Matthew; Pradier, Christian; Dabis, Francois; D'Arminio Monforte, Antonella; Smith, Colette; De Wit, Stephane; Kirk, Ole; Lundgren, Jens D.; Weber, Rainer

    2016-01-01

    Background.  Although human immunodeficiency virus (HIV)-positive persons on antiretroviral therapy (ART) frequently have chronic liver enzyme elevation (cLEE), the underlying cause is often unclear. Methods.  Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study participants without chronic viral hepatitis were observed to the earliest of cLEE (elevated aminotransferase ≥6 months), death, last follow-up, or January 2, 2014. Antiretroviral treatment exposure was categorized as fol...

  4. Aspartate aminotransferase-lymphocyte ratio index and systemic immune-inflammation index predict overall survival in HBV-related hepatocellular carcinoma patients after transcatheter arterial chemoembolization.

    Science.gov (United States)

    Yang, Zongguo; Zhang, Jianliang; Lu, Yunfei; Xu, Qingnian; Tang, Bozong; Wang, Qiang; Zhang, Wensi; Chen, Shishi; Lu, Lingqing; Chen, Xiaorong

    2015-12-15

    It has been suggested that lymphocytes play central roles in host antitumor immune responses and control cancer outcome. We reviewed the clinical parameters of 189 hepatocellular carcinoma (HCC) patients and investigated the prognostic significance of lymphocyte-related scores in HCC patients following transcatheter arterial chemoembolization (TACE). Survival analysis revealed that an elevated aspartate aminotransferase-lymphocyte ratio index (ALRI) > 57 and a systemic immune-inflammation index (SII) > 300 were negatively associated with overall survival in HBV-related HCC (HR = 2.181, P = 0.003 and HR = 2.453, P = 0.003; respectively). Spearman chi-square analysis showed that ALRI had a specificity of 82.4% and that SII index had a sensitivity of 71.9% for HCC overall survival. ALRI and SII had negative predictive values of 74.6% and 80%, respectively for HCC overall survival. Additionally, Barcelona Clinic Liver Cancer (BCLC) stage C patients had significantly higher ALRI and SII scores (both P SII scores (P SII should be used as negative predictive factors for overall survival in HBV-related HCC in clinical practice.

  5. Prediction of the Risk of Hepatocellular Carcinoma in Chronic Hepatitis C Patients after Sustained Virological Response by Aspartate Aminotransferase to Platelet Ratio Index

    Science.gov (United States)

    Lee, Keol; Sinn, Dong Hyun; Gwak, Geum-Youn; Cho, Hyun Chin; Jung, Sin-Ho; Paik, Yong-Han; Choi, Moon Seok; Lee, Joon Hyeok; Koh, Kwang Cheol; Paik, Seung Woon

    2016-01-01

    Background/Aims Following sustained virological response (SVR) for chronic hepatitis C (CHC) infection, patients with advanced fibrosis require regular monitoring for hepatocellular carcinoma (HCC). The aspartate aminotransferase to platelet ratio index (APRI) is a simple noninvasive surrogate marker known to reflect fibrosis. Methods We retrospectively analyzed 598 patients who achieved SVR with interferon-based therapy for CHC. Results Over a median of 5.1 years of follow-up, there were eight patients diagnosed with HCC and a 5-year cumulative incidence rate of 1.3%. The median pretreatment APRI was 0.83, which decreased to 0.29 after achieving SVR (p<0.001). Both the pre- and posttreatment indices were associated with HCC development. The 5-year cumulative HCC incidence rates were 0% and 2.8% for patients with pretreatment APRI <1.0 and ≥1.0, respectively (p=0.001) and 0.8% and 12.8% for patients with posttreatment APRI <1.0 and ≥1.0, respectively (p<0.001). Pretreatment APRI at a cutoff of 1.0 had a 100% negative predictive value until 10 years after SVR. Conclusions HCC development was observed among CHC patients who achieved SVR. The pre- and post-treatment APRI could stratify HCC risk, indicating that the APRI could be a useful marker to classify HCC risk in CHC patients who achieved SVR. However, given the small number of HCC patients, this finding warrants further validation. PMID:27114418

  6. Diagnostic accuracy of the aspartate aminotransferase-to-platelet ratio index for the prediction of hepatitis B-related fibrosis: a leading meta-analysis

    Directory of Open Access Journals (Sweden)

    Jin Wenwen

    2012-02-01

    Full Text Available Abstract Background The aspartate aminotransferase-to-platelet ratio index (APRI, a tool with limited expense and widespread availability, is a promising noninvasive alternative to liver biopsy for detecting hepatic fibrosis. The objective of this study was to systematically review the performance of the APRI in predicting significant fibrosis and cirrhosis in hepatitis B-related fibrosis. Methods Areas under summary receiver operating characteristic curves (AUROC, sensitivity and specificity were used to examine the accuracy of the APRI for the diagnosis of hepatitis B-related significant fibrosis and cirrhosis. Heterogeneity was explored using meta-regression. Results Nine studies were included in this meta-analysis (n = 1,798. Prevalence of significant fibrosis and cirrhosis were 53.1% and 13.5%, respectively. The summary AUCs of the APRI for significant fibrosis and cirrhosis were 0.79 and 0.75, respectively. For significant fibrosis, an APRI threshold of 0.5 was 84% sensitive and 41% specific. At the cutoff of 1.5, the summary sensitivity and specificity were 49% and 84%, respectively. For cirrhosis, an APRI threshold of 1.0-1.5 was 54% sensitive and 78% specific. At the cutoff of 2.0, the summary sensitivity and specificity were 28% and 87%, respectively. Meta-regression analysis indicated that the APRI accuracy for both significant fibrosis and cirrhosis was affected by histological classification systems, but not influenced by the interval between Biopsy & APRI or blind biopsy. Conclusion Our meta-analysis suggests that APRI show limited value in identifying hepatitis B-related significant fibrosis and cirrhosis.

  7. [Evaluation of the analytic performance of blood collection tubes (BD Vacutainer SST) for the screening of anti-HIV, anti-HTLV, anti-HCV, anti-HBc, anti-CMV antibodies, and of HBs, P24 HIV antigens, and of alanine aminotransferase].

    Science.gov (United States)

    Gobin, E; Desruelle, J M; Vigier, J P

    2001-02-01

    The Laboratory of Viral Diseases Immunology (Laboratoire d'Immunologie des Maladies Virales) of the Northern Region Blood Bank (Etablissement Français du Sang Nord de France) performs between 180.000 and 200.000 viral blood qualifications per year. The use of a serum gel separator evacuated tube should contribute to improve the quality of the pre-analytical phase. However, it must not impact negatively the analytical performances. We evaluated such tube within our specific environment and with the various reagents used in routine. The open study compared the BD Vacutainer plain tube (7 mL, non siliconised) with the BD Vacutainer SST tube (6 mL siliconised with serum gel separator) against the anti-HIV, anti-HTLV, anti-HCV, anti-HBc, anti-HBs, anti-CMV antibodies, the HBs, HIV P24 antigen and the alanine aminotransferase. The study objectives were to find potential gel interference; to verify the diagnostic sensitivity, reagents specificity, and reproducibility. The results analysis show: equivalent performances with the anti-HIV Ab (Anti HIV 1/2 recombinant--Biotest et Genscreen HIV 1/2--Sanofi), anti HIV WB Ab (New Lav Blot 1--Sanofi), anti-HBs Ab (Enzygnost anti-HBs micro--Behring), anti-HBc Ab (HBc Elisa Test System--Ortho), anti-CMV Ab (Enzygnost anti-CMV IgG + M--Behring) kits; lower performances with: The Vironostika HIV Uni Form II plus 0--Organon kit with a -3.5% signal decrease around the ratio R = 2.7 for positive anti-HIV Ab. The Elisa test System 3 Ag HBs-Ortho kit with an increase of the mean ratio of the negative Ag HBs samples; better performances with: the Vironostika HIV 1 Antigen--Organon kit with a +10% signal increase around the threshold ratio R = 1 for positive Ag HIV samples. This deserves further study to verify that the specificity is maintained. The HTLV Type 1 et 2 EIA--Ortho kit with +8% signal increase around the ratio R = 2 for positive anti-HTLV Ab samples without change of the specificity. The Ortho HCV 3.0 Elisa Test System and

  8. Antiretroviral Drugs and Risk of Chronic Alanine Aminotransferase Elevation in Human Immunodeficiency Virus (HIV)-Monoinfected Persons: The Data Collection on Adverse Events of Anti-HIV Drugs Study.

    Science.gov (United States)

    Kovari, Helen; Sabin, Caroline A; Ledergerber, Bruno; Ryom, Lene; Reiss, Peter; Law, Matthew; Pradier, Christian; Dabis, Francois; d'Arminio Monforte, Antonella; Smith, Colette; de Wit, Stephane; Kirk, Ole; Lundgren, Jens D; Weber, Rainer

    2016-01-01

    Background.  Although human immunodeficiency virus (HIV)-positive persons on antiretroviral therapy (ART) frequently have chronic liver enzyme elevation (cLEE), the underlying cause is often unclear. Methods.  Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study participants without chronic viral hepatitis were observed to the earliest of cLEE (elevated aminotransferase ≥6 months), death, last follow-up, or January 2, 2014. Antiretroviral treatment exposure was categorized as follows: no exposure and ongoing short- and long-term exposure (2 years RR = 1.26, 95% CI, 1.13-1.41); stavudine (2 years RR = 1.17, 95% CI, 1.03-1.32), and tenofovir disoproxil fumarate (2 years RR = 1.18, 95% CI, 1.05-1.32), but only short-term exposure to nevirapine (abacavir, and other protease inhibitors. Mortality did not differ between participants with and without cLEE. Conclusions.  Although didanosine, stavudine, nevirapine, and efavirenz have been described to be hepatotoxic, we additionally observed a consistent association between tenofovir and cLEE emerging within the first 2 years after drug initiation. This novel tenofovir-cLEE signal should be further investigated. PMID:26925429

  9. Antiretroviral Drugs and Risk of Chronic Alanine Aminotransferase Elevation in Human Immunodeficiency Virus (HIV)-Monoinfected Persons: The Data Collection on Adverse Events of Anti-HIV Drugs Study

    Science.gov (United States)

    Kovari, Helen; Sabin, Caroline A.; Ledergerber, Bruno; Ryom, Lene; Reiss, Peter; Law, Matthew; Pradier, Christian; Dabis, Francois; d'Arminio Monforte, Antonella; Smith, Colette; de Wit, Stephane; Kirk, Ole; Lundgren, Jens D.; Weber, Rainer

    2016-01-01

    Background. Although human immunodeficiency virus (HIV)-positive persons on antiretroviral therapy (ART) frequently have chronic liver enzyme elevation (cLEE), the underlying cause is often unclear. Methods. Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study participants without chronic viral hepatitis were observed to the earliest of cLEE (elevated aminotransferase ≥6 months), death, last follow-up, or January 2, 2014. Antiretroviral treatment exposure was categorized as follows: no exposure and ongoing short- and long-term exposure (2 years RR = 1.26, 95% CI, 1.13–1.41); stavudine (2 years RR = 1.17, 95% CI, 1.03–1.32), and tenofovir disoproxil fumarate (2 years RR = 1.18, 95% CI, 1.05–1.32), but only short-term exposure to nevirapine (<2 years RR = 1.44, 95% CI, 1.29–1.61), efavirenz (<2 years RR = 1.14, 95% CI, 1.03–1.26), emtricitabine (<2 years RR = 1.18, 95% CI, 1.04–1.33), and atazanavir (<2 years RR = 1.20, 95% CI, 1.04–1.38). Chronic liver enzyme elevation was not associated with use of lamivudine, abacavir, and other protease inhibitors. Mortality did not differ between participants with and without cLEE. Conclusions. Although didanosine, stavudine, nevirapine, and efavirenz have been described to be hepatotoxic, we additionally observed a consistent association between tenofovir and cLEE emerging within the first 2 years after drug initiation. This novel tenofovir-cLEE signal should be further investigated. PMID:26925429

  10. Effection of Pyridoxal- 5 '- phosphate on Determination of Alanine Aminotransferase activities%5'-磷酸吡哆醛对血清丙氨酸氨基转移酶活性测定的影响

    Institute of Scientific and Technical Information of China (English)

    朱柏林

    2012-01-01

    目的 研究丙氨酸氨基转移酶(Alanine Aminotraasferase,ALT) 检测试剂中 5'- 磷酸吡哆醛(Pyrldoxal - 5'-phosphate,PLP )的添加对血清ALT活性测定的影响.方法 以山东潍坊康华生物技术有限公司生产的丙氨酸氨基转移酶试剂(按照IFCC推荐方法配制,不含PLP)和在该品牌试剂中加入5'-磷酸吡哆醛溶液,分别用这两种试剂测定相同的新鲜临床标本280例,并对检测结果进行统计学比较.结果 使用含PLP的IFCC配方试剂较不含 PLP试剂的检测结果明显增高.结论 康华公司生产的丙氨酸氨基转移酶试剂添加PLP比较不添加PLP ALT活性增加近5%-40%,且两种试剂的ALT检测结果不能通过简单系数实现转换.

  11. 5'-磷酸吡哆醛影响血清丙氨酸氨基转移酶测定的研究%Effection of Pyridoxal -5'-phosphate on Determination of Alanine Aminotransferase activities

    Institute of Scientific and Technical Information of China (English)

    张宗彬; 鲍杰; 陈龙泉; 李传胜; 马洪波

    2007-01-01

    目的 研究丙氨酸氨基转移酶(Alanine Aminotraasferase,ALT)检测试剂中5'-磷酸吡哆醛(Pyrldoxal-5'-phos-phate,PLP)的添加对血清ALT活力测定的影响.方法 按IFCC推荐方法,自配ALT检测试剂(含PLP)和相应不添加PLP的检测试剂,分别用这两种试剂测定相同的新鲜临床标本,并对检测结果进行统计学比较.结果 使用含PLP的IFCC配方试剂较不含PLP试剂的检测结果明显增高.结论 健康人群和不同疾病人群由于个体差异,体内PLP含量不一,各组数据表明不含PLP配方试剂较IFCC配方检测结果明显偏低,因此两种配方的检测结果不能通过简单系数实现转换.

  12. PROPERTIES OF AMINOTRANSFERASES FROM TELADORSAGIA CIRCUMCINCTA

    Directory of Open Access Journals (Sweden)

    Noorzaid MUHAMAD

    2014-12-01

    Full Text Available Activities of several aminotransferases were measured in L3 and adult Teladorsagia circumcincta, but most of these had maximal activity of less than 8 nmol min-1 mg-1 protein. Only aspartate aminotransferase (AspAT and alanine aminotransferase (AlaAT activities exceeded this value and some kinetic properties of these enzymes were characterised. For L3 AspAT, the apparent Kms were 1.2 mM, 0.13 mM, 0.11 mM and 0.04 mM for aspartate, -ketoglutarate, glutamate and oxaloacetate, respectively, and the apparent Vmaxs were 960 nmol min-1 mg-1 protein for aspartate deamination and 420 nmol min-1 mg-1 protein in the direction of glutamate deamination. For L3 AlaAT, the apparent Kms were 5.2 mM, 0.5 mM, 0.5 mM and 1.2 mM for alanine, -ketoglutarate, glutamate and pyruvate, respectively, and apparent Vmaxs were 107 nmol min-1 mg-1 protein for alanine deamination and 48 nmol min-1 mg-1 protein for alanine formation. Both enzymes required exogenous pyridoxal 5′-phosphate for optimal activity. The equilibrium constants for the AspAT and AlaAT reactions were consistent with those estimated from the estimated kinetic parameters. From these parameters we infer that T. circumcincta AlaAT is present predominantly as a mitochondrial enzyme favouring pyruvate formation while AspAT is predominantly a cytosolic enzyme favouring glutamate formation.

  13. Degradation of pyrimidines in Saccharomyces kluyveri: transamination of beta-alanine

    DEFF Research Database (Denmark)

    Schnackerz, K D; Andersen, G; Dobritzsch, D;

    2008-01-01

    (GABA-AT). S. kluyveri has two aminotransferases, GABA aminotransferase ((Sk)Uga1p) with 80% and (Sk)Pyd4p with 55% identity to S. cerevisiae GABA-AT. (Sk)Pyd4p is a typical pyridoxal phosphate-dependent aminotransferase, specific for alpha-ketoglutarate (alpha KG), beta-alanine (BAL) and gamma...

  14. Inverse linear associations between liver aminotransferases and incident cardiovascular disease risk : The PREVEND study

    NARCIS (Netherlands)

    Kunutsor, Setor K.; Bakker, Stephan J. L.; Kootstra-Ros, Jenny E.; Blokzijl, Hans; Gansevoort, Ronald T.; Dullaart, Robin P. F.

    2015-01-01

    Background: Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) have been linked with an increased risk of type 2 diabetes, but their relationships with cardiovascular disease (CVD) are uncertain. We aimed to assess the associations of ALT and AST with CVD risk and determine their po

  15. Properties of serine: glyoxylate aminotransferase purified from Arabidopsis thaliana leaves

    Institute of Scientific and Technical Information of China (English)

    Maria Kendziorek; Andrzej Paszkowski

    2008-01-01

    The photorespiratory enzyme L-serine: glyoxylate aminotransferase (SGAT; EC 2.6.1.45) was purified from Arabidopsis thaliana leaves. The final enzyme was approximately 80% pure as revealed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with silver staining. The identity of the enzyme was confirmed by LC/MS/MS analysis.The molecular mass estimated by gel filtration chromatography on Sephadex G-150 under non-denaturing conditions, mass spectrometry (matrix-assisted laser desorption/ionization/time of flight technique) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis was 82.4 kDa,42.0 kDa, and 39.8 kDa, respectively, indicating dimer as the active form. The optimum Ph value was 9.2. The enzyme activity was inhibited by aminooxyacetate and β-chloro-L-alanine both compounds reacting with the carbonyl group of pyridoxal phosphate. The enzyme's transaminating activity with L-alanine and glyoxylate as substrates was approximately 55% of that observed with L-serine and glyoxylate, The lower Km value (1.25 Mm) for L-alanine, compared with that of other plant SGATs, and the kcat/Km(Ala) ratio being approximately 2-fold higher than kcat/Km(Ser) suggested that, during photorespiration, Ala and Ser are used by Arabidopsis SGAT with equal efficiency as amino group donors for glyoxylate. The equilibrium constant (Keq), derived from the Haldane relation, for the transamination reaction between L-serine and glyoxylate with the formation of hydroxypyruvate and glycine was 79.1, strongly favoring glycine synthesis. However, it was accompanied by a low Km value of 2.83 Mm for glycine. A comparison of some kinetic properties of the studied enzymes with the recombinant Arabidopsis SGATs previously obtained revealed substantial differences. The ratio of the velocity of the transamination reaction with L-alanine and glyoxylate as substrates versus that with L-serine and glyoxylate was 1:1.8 for the native enzyme, whereas it was 1: 7 for the recombinant SGAT

  16. Comparative aspects of aminotransferases in the rat, pigeon and rainbow trout.

    Science.gov (United States)

    Cornish, E C; Cussen, C M; Hird, F J; Todd, P E

    1978-01-01

    1. The activities of aminotransferases catalysing the transfer of amino groups from aspartate, alanine and leucine to 2-oxoglutarate in different tissues of the rat, pigeon and trout have been determined. 2. Alanine-2-oxoglutarate aminotransferase was high in the liver of the rat and trout and low in that of the pigeon. 3. Aspartate-2-oxoglutarate aminotransferase was usually the dominant aminotransferase in all tissues and was highest in oxidative tissues where the TCA cycle is active. Its activity in the various livers is not correlated with the function of aspartate in nitrogen excretion. 4. The activity of aspartate-2-oxoglutarate aminotransferase in oxidative tissues argues that aspartate in conjunction with this enzyme serves as a buffer of oxaloacetate to keep the TCA cycle running and/or to mediate the transfer of reducing equivalents across mitochondrial membranes. PMID:318383

  17. Weaning Induced Hepatic Oxidative Stress, Apoptosis, and Aminotransferases through MAPK Signaling Pathways in Piglets

    Science.gov (United States)

    Luo, Zhen; Zhu, Wei; Guo, Qi; Luo, Wenli; Zhang, Jing; Xu, Weina

    2016-01-01

    This study investigated the effects of weaning on the hepatic redox status, apoptosis, function, and the mitogen-activated protein kinase (MAPK) signaling pathways during the first week after weaning in piglets. A total of 12 litters of piglets were weaned at d 21 and divided into the weaning group (WG) and the control group (CG). Six piglets from each group were slaughtered at d 0 (d 20, referred to weaning), d 1, d 4, and d 7 after weaning. Results showed that weaning significantly increased the concentrations of hepatic free radicals H2O2 and NO, malondialdehyde (MDA), and 8-hydroxy-2′-deoxyguanosine (8-OHdG), while significantly decreasing the inhibitory hydroxyl ability (IHA) and glutathione peroxidase (GSH-Px), and altered the level of superoxide dismutase (SOD). The apoptosis results showed that weaning increased the concentrations of caspase-3, caspase-8, caspase-9 and the ratio of Bax/Bcl-2. In addition, aspartate aminotransferase transaminase (AST) and alanine aminotransferase (ALT) in liver homogenates increased after weaning. The phosphorylated JNK and ERK1/2 increased, while the activated p38 initially decreased and then increased. Our results suggested that weaning increased the hepatic oxidative stress and aminotransferases and initiated apoptosis, which may be related to the activated MAPK pathways in postweaning piglets.

  18. Clinical characteristics of elders with elevated alanine aminotransferase and its association with ultrasound diagnosis of fatty liver%丙氨酸氨基转移酶升高的老年人的临床特征与超声诊断脂肪肝的相关性

    Institute of Scientific and Technical Information of China (English)

    王健生; 徐惠明; 陈小芳; 薛骏明; 周明霞

    2012-01-01

    Objective To evaluate clinical characteristics associated withof elders with elevated alanine aminotransferase (ALT) and its association with ultrasound diagnosis of fatty liver. Methods The physical examination data of 1 054 elders were cross - sectionally analyzed from May. 2010 to Jun. 2012. There were 154 persons with elevated ALT, in which 54 cases were caused by hepatitis B and alcohol abuse. 100 subjects were included into the present study. Subjects were divided into NAFLD group (50 cases) and control group (50 cases). BMI, lipid metabolism, ALT, diabetes mellitus and so on were analyzed. Results In 100 cases of included individuals, 50% were diagnosed as NAFLD using ultrasonography. Patients with NAFLD showed higher (BMI) (P =0.013) , diabetes prevalence (P =0.019) and tri-glycerides (P =0.022) compared with individuals without NAFLD. Multivariate regression analysis showed that BMI (OR = 1.454; 95% CI: 1.139 -1.856; P= 0.003) and diabetes mellitus (OR =3. 378; 95% CI: 1.343 -8.494, P = 0.01) were independent risk factor associated with NAFLD. Conclusion Clinical features such as history of diabetes and high BMI may predict the presence of NAFLD on ultrasonography inpatients with elevated ALT but negative hepatitis.%目的 评估丙氨酸氨基转移酶(ALT)升高的老年人的临床特征与脂肪肝的相关性.方法 通过对2010年5月-2010年6月来我院行健康体检的1 054例老年体检者进行横断面研究,发现154例ALT升高,其中54例有乙型肝炎或者酒精摄入过量,最终100例入选本组研究.被分为非酒精性脂肪肝组(NAFLD)50例和对照组50例.分别进行体格检查计算体质量指数(BMI)、脂质代谢、ALT及糖尿病等调查.结果 在100例患者中,超声诊断50%有非酒精性脂肪肝,与无脂肪肝的患者相比,非酒精性脂肪肝患者有糖尿病史(P=0.019),并有较高的BMI (P=0.013)和甘油三脂(P=0.022).多变量回归分析显示BMI和糖尿病为脂肪

  19. Aspartate aminotransferase to platelet ratio index and sustained virologic response are associated with progression from hepatitis C associated liver cirrhosis to hepatocellular carcinoma after treatment with pegylated interferon plus ribavirin

    Science.gov (United States)

    Ng, Khai-Jing; Tseng, Chih-Wei; Chang, Ting-Tsung; Tzeng, Shinn-Jia; Hsieh, Yu-Hsi; Hung, Tsung-Hsing; Huang, Hsiang-Ting; Wu, Shu-Fen; Tseng, Kuo-Chih

    2016-01-01

    Background The aim of this study was to evaluate the clinically significant predictors of hepatocellular carcinoma (HCC) development among hepatitis C virus (HCV) cirrhotic patients receiving combination therapy. Patients and methods One hundred and five compensated cirrhosis patients who received pegylated interferon plus ribavirin between January 2005 and December 2011 were enrolled. All the patients were examined with abdominal sonography and liver biochemistry at baseline, end of treatment, and every 3–6 months posttreatment. The occurrence of HCC was evaluated every 3–6 months posttreatment. Results A total of 105 patients were enrolled (mean age 58.3±10.4 years). The average follow-up time for each patient was 4.38 years (standard deviation 1.73 years; range 1.13–9.27 years). Fifteen (14.3%) patients developed HCC during follow-up period. Thirteen of them had high baseline aspartate aminotransferase to platelet ratio index (APRI) (ie, an APRI >2.0). Multivariate analysis showed that those without sustained virologic response (SVR) (hazard ratio [HR] 5.795; 95% confidence interval [CI] 1.370–24.5; P=0.017) and high APRI (HR 5.548; 95% CI 1.191–25.86; P=0.029) had a significantly higher risk of HCC occurrence. The cumulative incidence of HCC was significantly higher (P=0.009) in patients without SVR (3-year cumulative incidence 21.4%; 95% CI 7.4%–35.5%; 5-year cumulative incidence 31.1%; 95% CI 11.2%–51.1%) compared to those with SVR (3- and 5-year cumulative incidence 6.2%; 95% CI 0%–1.3%). Further, the cumulative incidence of HCC was significantly higher (P=0.006) in patients with high APRI (3-year cumulative incidence 21.8%; 95% CI 8.2%–35.3%; 5-year cumulative incidence 30.5%, 95% CI 11.8%–49.3%) compared to those with low APRI (3- and 5-year cumulative incidence 4.2%, 95% CI 0%–1.0%). Conclusion In HCV-infected cirrhotic patients who received combination therapy, APRI and SVR are the two major predictors of HCC development. PMID

  20. 丙氨酸转氨酶正常的慢性乙型肝炎病毒感染者的肝脏病理学分析%Pathological analysis of liver tissues from chronic hepatitis B patients with normal alanine aminotransferase levels

    Institute of Scientific and Technical Information of China (English)

    谭友文; 史正全; 於学军; 杨丽君; 陈丽; 孙丽

    2010-01-01

    目的 了解ALT正常的慢性HBV感染者的肝脏病理学改变及其影响因素.方法 观察632例ALT正常的慢性HBV感染者,采用超声定位穿刺取肝组织,行HE染色、纤维Masson染色,HBsAg和HBcAg免疫组织化学染色,观察Knodell坏死炎症评分和Ishak纤维化评分,并分析它们与年龄、ALT水平、血清HBV DNA载量、HBsAg和HBcAg肝组织表达的关系.两均数比较采用t检验,多均数比较采用单因素方差分析及q检验,计数资料采用x2检验.结果 632例ALT正常的HBV感染者中,中度炎症坏死167例,占26.4%,重度炎症坏死26例,占4.1%,中度纤维化217例,占34.3%,重度纤维化(肝硬化)52例,占8.2%.Knodell坏死炎症评分和Ishak纤维化评分在高ALT层次组比低ALT层次组高,在女性高ALT层次组比男性高ALT层次组高,在年龄>40岁组比年龄≤20岁组高(q=19.63,P<0.05).肝组织损伤程度在HBV DNA载量≤5×105拷贝/L组明显轻于HBV DNA 5×105~1×107拷贝/L、1×107~1×109拷贝/L和>1×109拷贝/L组(Knodell评分,q=3.87、2.87、6.34;Ishak评分,q=2.64、2.64、5.54;均P<0.05),在不同HBV DNA载量复制组之间差异无统计学意义(F=1.35,P>0.05).HBsAg(F=1.65、0.73,均P>0.05)和HBcAg(F=0.17、1.29,均P>0.05)肝组织表达与Knodell坏死炎症评分和Ishak纤维化评分差异均无统计学意义.结论 可检测到HBV DNA的ALT持续正常的慢性HBV感染患者应考虑进行肝组织活检,特别是年龄>40岁且ALT在(0.75~1.00)×正常值上限者.%Objective To study the liver histological changes in chronic hepaitits B (CHB) patients with normal serum alanine aminotransferase (ALT) levels and the related factors. Methods Six hundred and thirty-two CHB patients with normal ALT levels had undergone ultrasound guided percutaneous liver biopsies. All specimen were examined by HE staining, collagen fiber Masson staining and immunohistochemical staining for hepatitis B surface antigen (HBsAg) and hepatitis B core

  1. Aspartate aminotransferase (AST) blood test

    Science.gov (United States)

    ... Saunders; 2016:chap 73. Read More Acute kidney failure Acute pancreatitis Alanine transaminase (ALT) blood test ALP - blood test Burns Cardiac catheterization Enzyme Heart attack Hemolytic anemia Hepatic Liver cancer - hepatocellular carcinoma Liver disease Mononucleosis Muscular ...

  2. 4073对夫妻孕前优生健康检查传染病感染指标及丙氨酸氨基转移酶检测结果分析%Analysis of Detection Results of Communicable Disease Infectious Indicators and Alanine Aminotransferase of 4 073 Couples After Pre-pregnancy Eugenics Health Examination

    Institute of Scientific and Technical Information of China (English)

    赵庆伟; 马书军; 张凌薇; 刘云

    2016-01-01

    Objective To understand the infectious situation of hepatitis B virus( HBV),treponema pallidum (TP),human immunodeficiency virus( HIV)and abnormal rate of alanine aminotransferase( ALT)of the pre - pregnancy couples,so as to take effective measures to prevent the mutual diffusion between couples and the vertical transmission from mother to child and ensure their health. Methods 4 073 couples,who met the inclusion criteria and had taken the pre - pregnancy physical examination in Hebei Women and Children's Health Center from 2012 to 2014,were selected as the research objects retrospectively. The detection results of HBV,TP,HIV,and ALT were collected and analyzed. Results Among 4 073 coupes,the positive rate of hepatitis B virus surface antigen(HBsAg)was 3. 44% (280 / 8 146),the positive rate of TP rapid plasma reagin(RPR)and TP particle agglutination(TPPA)test was 0. 34% (28 / 8 146),the positive rate of anti - HIV1 / 2 was 0, and the abnormal rate of ALT was 4. 82% (393 / 8 146). The positive - HBsAg rate and the ALT abnormal rate of male were higher than those of the female(P ﹤ 0. 05). Among 168 males with positive - HBsAg,115 were all positive HBsAg,hepatitis B virus e antibody(HBeAb)and hepatitis B virus core antibody(HBcAb),23 all positive HBsAg,hepatitis B virus e antigen (HBeAg)and HBcAb,and 30 with other conditions;among the spouses of 115 males,34 were all negative HBsAg,hepatitis B virus surface antibody( HBsAb),HBeAg、HBeAb、HBcAb. Among the 112 females with positive - HBsAg,75 were all positive HBsAg,HBeAb and HBcAb,16 all positive HBsAg,HBeAg,and HBcAb,21 with other conditions;among the spouses of 112 females,13 were all negative HBsAg,HBsAb,HBeAg,HBeAb,and HBcAb. Among 28 participants with RPR and TPPA of positive attributes,9 couples were all positive RPR and TPPA. Among 236 males with abnormal ALT,14 were all positive HBsAg,HBeAg and HBcAb;among 157 females with abnormal ALT,7 were all positive HBsAg,HBeAg and HBcAb. The positive rate of HBsAg in

  3. The effect of isotretinoin on triglycerides and liver aminotransferases Influência da isotretinoína nas transaminases hepáticas e triglicerídeos

    OpenAIRE

    Andreia Salezze Vieira; Vanessa Beijamini; Ana Carolina Melchiors

    2012-01-01

    BACKGROUND: Isotretinoin has been used to treat the most severe cases of acne; however, it may provoke adverse events in mucocutaneous and hepatic tissues, lead to alterations in lipid levels and cause teratogenicity. OBJECTIVE: The objective of this study was to evaluate the profile of changes in alanine aminotransferase (ALT), aspartate aminotransferase (AST) and triglyceride levels in patients who had been treated with oral isotretinoin dispensed by the São Mateus/ES pharmacy for special d...

  4. Role of aminotransferases in glutamate metabolism of human erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Ellinger, James J. [University of Wisconsin-Madison, Department of Biochemistry (United States); Lewis, Ian A. [Princeton University, Lewis-Sigler Institute for Integrative Genomics (United States); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, Department of Biochemistry (United States)

    2011-04-15

    Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from {alpha}-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional {sup 1}H-{sup 13}C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

  5. Relationship Between Serum Aminotransferase Levels and Metabolic Disorders in Northern China

    Directory of Open Access Journals (Sweden)

    Jq Niu

    2012-02-01

    Full Text Available Background: Increasing evidence suggests an association between ele­vated serum aminotransferase levels and metabolic disorders (metabolic syndrome, hyperlipemia and diabetes mellitus. However, the significance of relatively low levels of aminotransferases in relation to metabolic disorders has not been fully investigated in the general population. We inves­tigated the association between serum amiontransferase levels and metabolic disorders using data from a survey in Jilin province, China.Methods: In 2007, a survey was conducted throughout Jilin, China, covering both urban and rural areas. A total of 3835 people, 18 to 79 years old including 1761 men and 2074 women, underwent real-time ultrasonography, blood tests including aspartate aminotransferase and alanine aminotransferase, and had interviews with a structured questionnaire.Results: Serum aminotransferase levels within the normal range were asso­ciated with metabolic syndrome independent of age, occupation, cultural and educational level, income, body mass index, waist circumference, smoking, and alcohol intake. Compared with the lowest level (50 IU/L were 1.92, 2.50, 2.97, and 3.52 in men, and 1.38 , 1.54, 3.06, and 2.62 in women, respectively. Near-normal serum aminotransferase levels asso­ciated with hyperlipemia, NAFLD, DM were also found in the study.Conclusions: Normal to near-normal serum aminotransferase levels are associated with metabolic disorders. Serum ALT levels of 21-25 IU/L for men, and 17-22 IU/L for women are suggested as cutoff levels that detect metabolic disorders affecting the liver.

  6. Effects of pyridoxine on growth performance and plasma aminotransferases and homocysteine of white pekin ducks.

    Science.gov (United States)

    Xie, Ming; Tang, Jing; Wen, Zhiguo; Huang, Wei; Hou, Shuisheng

    2014-12-01

    A dose-response experiment with seven supplemental pyridoxine levels (0, 0.66, 1.32, 1.98, 2.64, 3.30, and 3.96 mg/kg) was conducted to investigate the effects of pyridoxine on growth performance and plasma aminotransferases and homocysteine of White Pekin ducks and to estimate pyridoxine requirement for these birds. A total of 336 one-day-old male White Pekin ducks were divided to 7 experimental treatments and each treatment contained 8 replicate pens with 6 birds per pen. Ducks were reared in raised wire-floor pens from hatch to 28 d of age. At 28 d of age, the weight gain, feed intake, feed/gain, and the aspartate aminotransferase, alanine aminotransferase, and homocysteine in plasma of ducks from each pen were all measured. In our study, the pyridoxine deficiency of ducks was characterized by growth depression, decreasing plasma aspartate aminotransferase activity and increasing plasma homocysteine. The ducks fed vitamin B6-deficient basal diets had the worst weight gain and feed/gain among all birds and this growth depression was alleviated (pducks. The ducks fed basal diets had much lower aspartate aminotransferase activity and higher homocysteine level in plasma compared with other birds fed pyridoxine-supplemented diets (pducks from hatch to 28 days of age was 2.44 mg/kg for feed/gain and 2.08 mg/kg for plasma aspartate aminotransferase and the corresponding total requirements of this vitamin for these two criteria were 4.37 and 4.01 mg/kg when the pyridoxine concentration of basal diets was included, respectively. All data suggested that pyridoxine deficiency could cause growth retardation in ducks and the deficiency of this vitamin could be indicated by decreasing plasma aspartate aminotransferase activity and increasing plasma homocysteine.

  7. Application of ratio index of aspartate aminotransferase and platelet ratio on liver fibrosis classification of patients with chronic hepatitis B%慢性乙型肝炎患者肝纤维化分级中AST/PLT比值指数的临床研究1

    Institute of Scientific and Technical Information of China (English)

    隗功贤; 王志鹏

    2013-01-01

      目的评价天门冬氨酸氨基转移酶(AST)与血小板(PLT)比值在预测慢性乙型肝炎(CHB)肝纤维化分级中的作用。方法将178例CHB合并肝纤维化患者肝组织纤维化程度进行Ishak分期,同时检测患者AST和PLT,计算AST与PLT比值指数(APRI)。比较患者不同肝纤维化分期与APRI间的关系,通过APRI的受试者工作特征(ROC)曲线下面积,分析其预测显著肝纤维化及肝硬化的准确率,并对CHB肝纤维化患者抗病毒治疗前后肝组织纤维化分期和APRI的变化进行对比分析。结果APRI与肝纤维化程度呈正比(P =0.001),APRI预测CHB进展为显著肝纤维化ROC曲线下面积为0.795,而预测肝硬化的ROC曲线下面积为0.714(P =0.003),APRI >1.5和>2分别为显著肝纤维化和肝硬化的截断点,其阳性预测值分别为96%和75%,阴性预测值分别为44%和74%。CHB患者经抗病毒药物治疗后,肝组织学检查结果显示其纤维化程度比治疗前明显减轻,而APRI也明显降低。结论 APRI可作为预测CHB患者发生显著肝纤维化及肝硬化的指标之一。%Objective To evaluate the aspartate aminotransferase (AST) and platelet (PLT) ratio in predicting classification of chronic hepatitis B (CHB) based on liver fibrosis. Methods Ishak staging of liver fibrosis of 178 cases with CHB was carried out, and AST, PLT levels were detected simutaneously and the ratio of AST and PLT (APRI) was calculated. By anaysis of APRI receiver operating characteristic (ROC) area under the curve, the accuracy of prediction of significant fibrosis and cirrhosis and changes of liver fibrosis and APRI before and after antiviral treatment were analyzed. Results APRI was positively related to the degree of liver fibrosis (P = 0.001). The area under the ROC curve of APRI prediction of CHB progression to significant fibrosis was 0.795, while was 0.714 for prediction of progression to cirrhosis (P = 0

  8. 2006年-2009年新邵县食品、公共场所从业人员乙肝五项和ALT检测结果分析%Analysis of the five Hepatitis B test and alanine aminotransferase (ALT) levels among personnel of food industry and public place in Xinshao county from 2006 to 2009

    Institute of Scientific and Technical Information of China (English)

    岳友宏

    2011-01-01

    Objective:The purpose of the study is to understand the distribution of HBsAg, HBsAb, HBeAg, HBeAb, HBcAb and the abnormity of ALT among personnel of food industry and public place to provide scientific evidence for Prevention and cure of Hepatitis B.Methods: The five test for Hepatitis B were detected by ELISA and ALT with Reitman - Frankel test.Results:There were 8271 personnel tested in 2006 - 2009 ,From 2006 to 2009, ratio of infection decreased from 9.47% to 6.03%.In age group from 17 to 25 、26 to 40、41 to 55 ,ratio of infection was 5.21% ,6.91%, 10.60% respectively.Ratio of abnormal ALT is 5.45% among the combined positives of HBsAg, HBeAg, HBcAb, is 4.32% among the combined positives of HBsAg, HBeAb,HBcAb.There is not significant statistical difference with P -value( > 0.05).Conclusion: Ratio of infection of Hepatitis B had a tendency for decreasing but keep on a higher proportion in personnel of food industry and public place, the measure of epidemic prevention should be taken in further.%目的:了解食品、公共场所从业人员乙肝五项及丙氨酸氨基转移酶(ALT)异常情况,为乙肝防治提供科学依据.方法:用酶联免疫吸附试验(ELISA)进行乙肝五项标志物检测,用赖氏法测定ALT,并进行分析比较.结果:在2006年-2009年共检测8217人,乙肝感染率从2006年9.47%下降至2009年6.03%,在17岁~25岁、26岁~40岁、41岁~55岁三年龄段感染率分别为:5.21%、6.91%、10.60%.在大三阳(HBsAg、HBeAg和HBcAb均阳性)中,ALT异常率为5.45%,在小三阳(HBsAg、HBeAb、HBcAb均阳性)为4.32%,没有显著性差异,x2=0.37,P>0.05.结论:从业人员乙肝感染率呈下降趋势,但仍维持在较高水平,需进一步预防控制.

  9. Structural studies of Pseudomonas and Chromobacterium ω-aminotransferases provide insights into their differing substrate specificity

    International Nuclear Information System (INIS)

    The X-ray structures of two ω-aminotransferases from P. aeruginosa and C. violaceum in complex with an inhibitor offer the first detailed insight into the structural basis of the substrate specificity of these industrially important enzymes. The crystal structures and inhibitor complexes of two industrially important ω-aminotransferase enzymes from Pseudomonas aeruginosa and Chromobacterium violaceum have been determined in order to understand the differences in their substrate specificity. The two enzymes share 30% sequence identity and use the same amino acceptor, pyruvate; however, the Pseudomonas enzyme shows activity towards the amino donor β-alanine, whilst the Chromobacterium enzyme does not. Both enzymes show activity towards S-α-methylbenzylamine (MBA), with the Chromobacterium enzyme having a broader substrate range. The crystal structure of the P. aeruginosa enzyme has been solved in the holo form and with the inhibitor gabaculine bound. The C. violaceum enzyme has been solved in the apo and holo forms and with gabaculine bound. The structures of the holo forms of both enzymes are quite similar. There is little conformational difference observed between the inhibitor complex and the holoenzyme for the P. aeruginosa aminotransferase. In comparison, the crystal structure of the C. violaceum gabaculine complex shows significant structural rearrangements from the structures of both the apo and holo forms of the enzyme. It appears that the different rigidity of the protein scaffold contributes to the substrate specificity observed for the two ω-aminotransferases

  10. A gene duplication led to specialized gamma-aminobutyrate and beta-alanine aminotransferase in yeast

    DEFF Research Database (Denmark)

    Andersen, Gorm; Andersen, Birgit; Dobritzsch, D.;

    2007-01-01

    to characterize the substrate specificity and kinetic parameters of the four enzymes. It was found that the cofactor pyridoxal 5'-phosphate is needed for enzymatic activity and alpha-ketoglutarate, and not pyruvate, as the amino group acceptor. SkPyd4p preferentially uses BAL as the amino group donor (V...

  11. Value of two noninvasive methods to detect progression of fibrosis among HCV carriers with normal aminotransferases.

    Science.gov (United States)

    Colletta, Cosimo; Smirne, Carlo; Fabris, Carlo; Toniutto, Pierluigi; Rapetti, Rachele; Minisini, Rosalba; Pirisi, Mario

    2005-10-01

    The course of hepatitis C virus (HCV) infection carriers with normal/near-normal aminotransferases (NALT) is usually mild; however, in a few, fibrosis progression occurs. We aimed to verify whether monitoring by liver biopsy might be replaced by noninvasive methods and to identify factors associated with fibrosis progression in patients with persistently normal alanine aminotransferases. We studied 40 untreated HCV-RNA-positive subjects (22 male; median age, 44 years), who underwent two liver biopsies, with a median interval of 78.5 months, during which alanine aminotransferase concentrations (median number of determinations: 12) never exceeded 1.2 times the upper normal limit. Within 9 months from the second biopsy, they were tested by the shear elasticity probe (Fibroscan) and the artificial intelligence algorithm FibroTest. METAVIR fibrosis scores were analyzed in relationship to demographic, clinical, and viral parameters. Weighted kappa analysis was used to verify whether the results of noninvasive methods agreed with histology. Significant fibrosis (> or = F2), present at the first biopsy in only one patient (2.5%), was observed at the second biopsy in 14 patients (35%). At multivariate analysis, excess alcohol consumption in the past (>20 g/d; P = .017) and viral load (>8.0 x 10(6) copies/mL; P = .021) were independent predictors of progression. In identifying patients with significant fibrosis, inter-rater agreement was excellent for Fibroscan (weighted kappa = 1.0), and poor for FibroTest (weighted kappa = -0.041). In conclusion, among HCV carriers with NALT, Fibroscan is superior to the FibroTest in the noninvasive identification of fibrosis, for which excess alcohol consumption in the past and high viral load represent risk factors.

  12. Clinical relevance and discriminatory value of elevated liver aminotransferase levels for dengue severity.

    Directory of Open Access Journals (Sweden)

    Linda K Lee

    Full Text Available BACKGROUND: Elevation of aspartate aminotransferase (AST and alanine aminotransferase (ALT is prominent in acute dengue illness. The World Health Organization (WHO 2009 dengue guidelines defined AST or ALT ≥ 1000 units/liter (U/L as a criterion for severe dengue. We aimed to assess the clinical relevance and discriminatory value of AST or ALT for dengue hemorrhagic fever (DHF and severe dengue. METHODOLOGY/PRINCIPAL FINDINGS: We retrospectively studied and classified polymerase chain reaction positive dengue patients from 2006 to 2008 treated at Tan Tock Seng Hospital, Singapore according to WHO 1997 and 2009 criteria for dengue severity. Of 690 dengue patients, 31% had DHF and 24% severe dengue. Elevated AST and ALT occurred in 86% and 46%, respectively. Seven had AST or ALT ≥ 1000 U/L. None had acute liver failure but one patient died. Median AST and ALT values were significantly higher with increasing dengue severity by both WHO 1997 and 2009 criteria. However, they were poorly discriminatory between non-severe and severe dengue (e.g., AST area under the receiver operating characteristic [ROC] curve=0.62; 95% confidence interval [CI]: 0.57-0.67 and between dengue fever (DF and DHF (AST area under the ROC curve=0.56; 95% CI: 0.52-0.61. There was significant overlap in AST and ALT values among patients with dengue with or without warning signs and severe dengue, and between those with DF and DHF. CONCLUSIONS: Although aminotransferase levels increased in conjunction with dengue severity, AST or ALT values did not discriminate between DF and DHF or non-severe and severe dengue.

  13. Brain alanine formation as an ammonia-scavenging pathway during hyperammonemia

    DEFF Research Database (Denmark)

    Dadsetan, Sherry; Kukolj, Eva; Bak, Lasse Kristoffer;

    2013-01-01

    Hyperammonemia is a major etiological toxic factor in the development of hepatic encephalopathy. Brain ammonia detoxification occurs primarily in astrocytes by glutamine synthetase (GS), and it has been proposed that elevated glutamine levels during hyperammonemia lead to astrocyte swelling and c...... thereby reducing the glutamine level in brain. Thus, GS could be a potential drug target in the treatment of hyperammonemia in patients with hepatic encephalopathy.......Hyperammonemia is a major etiological toxic factor in the development of hepatic encephalopathy. Brain ammonia detoxification occurs primarily in astrocytes by glutamine synthetase (GS), and it has been proposed that elevated glutamine levels during hyperammonemia lead to astrocyte swelling...... and cerebral edema. However, ammonia may also be detoxified by the concerted action of glutamate dehydrogenase (GDH) and alanine aminotransferase (ALAT) leading to trapping of ammonia in alanine, which in vivo likely leaves the brain. Our aim was to investigate whether the GS inhibitor methionine sulfoximine...

  14. Kynurenine Aminotransferase Isozyme Inhibitors: A Review

    Directory of Open Access Journals (Sweden)

    Alireza Nematollahi

    2016-06-01

    Full Text Available Kynurenine aminotransferase isozymes (KATs 1–4 are members of the pyridoxal-5’-phosphate (PLP-dependent enzyme family, which catalyse the permanent conversion of l-kynurenine (l-KYN to kynurenic acid (KYNA, a known neuroactive agent. As KATs are found in the mammalian brain and have key roles in the kynurenine pathway, involved in different categories of central nervous system (CNS diseases, the KATs are prominent targets in the quest to treat neurodegenerative and cognitive impairment disorders. Recent studies suggest that inhibiting these enzymes would produce effects beneficial to patients with these conditions, as abnormally high levels of KYNA are observed. KAT-1 and KAT-3 share the highest sequence similarity of the isozymes in this family, and their active site pockets are also similar. Importantly, KAT-2 has the major role of kynurenic acid production (70% in the human brain, and it is considered therefore that suitable inhibition of this isozyme would be most effective in managing major aspects of CNS diseases. Human KAT-2 inhibitors have been developed, but the most potent of them, chosen for further investigations, did not proceed in clinical studies due to the cross toxicity caused by their irreversible interaction with PLP, the required cofactor of the KAT isozymes, and any other PLP-dependent enzymes. As a consequence of the possibility of extensive undesirable adverse effects, it is also important to pursue KAT inhibitors that reversibly inhibit KATs and to include a strategy that seeks compounds likely to achieve substantial interaction with regions of the active site other than the PLP. The main purpose of this treatise is to review the recent developments with the inhibitors of KAT isozymes. This treatise also includes analyses of their crystallographic structures in complex with this enzyme family, which provides further insight for researchers in this and related studies.

  15. Inhibitors of alanine racemase enzyme: a review.

    Science.gov (United States)

    Azam, Mohammed Afzal; Jayaram, Unni

    2016-08-01

    Alanine racemase is a fold type III PLP-dependent amino acid racemase enzyme catalysing the conversion of l-alanine to d-alanine utilised by bacterial cell wall for peptidoglycan synthesis. As there are no known homologs in humans, it is considered as an excellent antibacterial drug target. The standard inhibitors of this enzyme include O-carbamyl-d-serine, d-cycloserine, chlorovinyl glycine, alaphosphin, etc. d-Cycloserine is indicated for pulmonary and extra pulmonary tuberculosis but therapeutic use of drug is limited due to its severe toxic effects. Toxic effects due to off-target affinities of cycloserine and other substrate analogs have prompted new research efforts to identify alanine racemase inhibitors that are not substrate analogs. In this review, an updated status of known inhibitors of alanine racemase enzyme has been provided which will serve as a rich source of structural information and will be helpful in generating selective and potent inhibitor of alanine racemase. PMID:26024289

  16. Substrate Specificity and Structure of Human aminoadipate aminotransferase/kynurenine aminotransferase II

    Energy Technology Data Exchange (ETDEWEB)

    Han, Q.; Cai, T; Tagle, D; Robinson, H; Li, J

    2009-01-01

    KAT (kynurenine aminotransferase) II is a primary enzyme in the brain for catalysing the transamination of kynurenine to KYNA (kynurenic acid). KYNA is the only known endogenous antagonist of the N-methyl-D-aspartate receptor. The enzyme also catalyses the transamination of aminoadipate to alpha-oxoadipate; therefore it was initially named AADAT (aminoadipate aminotransferase). As an endotoxin, aminoadipate influences various elements of glutamatergic neurotransmission and kills primary astrocytes in the brain. A number of studies dealing with the biochemical and functional characteristics of this enzyme exist in the literature, but a systematic assessment of KAT II addressing its substrate profile and kinetic properties has not been performed. The present study examines the biochemical and structural characterization of a human KAT II/AADAT. Substrate screening of human KAT II revealed that the enzyme has a very broad substrate specificity, is capable of catalysing the transamination of 16 out of 24 tested amino acids and could utilize all 16 tested alpha-oxo acids as amino-group acceptors. Kinetic analysis of human KAT II demonstrated its catalytic efficiency for individual amino-group donors and acceptors, providing information as to its preferred substrate affinity. Structural analysis of the human KAT II complex with alpha-oxoglutaric acid revealed a conformational change of an N-terminal fraction, residues 15-33, that is able to adapt to different substrate sizes, which provides a structural basis for its broad substrate specificity.

  17. Substrate Specificity and Structure of Human Aminoadipate Aminotransferase/kynurenine Aminotransferase II

    Energy Technology Data Exchange (ETDEWEB)

    Han,Q.; Cai, T.; Tagle, D.; Robinson, H.; Li, J.

    2008-01-01

    KAT (kynurenine aminotransferase) II is a primary enzyme in the brain for catalysing the transamination of kynurenine to KYNA (kynurenic acid). KYNA is the only known endogenous antagonist of the N-methyl-D-aspartate receptor. The enzyme also catalyses the transamination of aminoadipate to a-oxoadipate; therefore it was initially named AADAT (aminoadipate aminotransferase). As an endotoxin, aminoadipate influences various elements of glutamatergic neurotransmission and kills primary astrocytes in the brain. A number of studies dealing with the biochemical and functional characteristics of this enzyme exist in the literature, but a systematic assessment of KAT II addressing its substrate profile and kinetic properties has not been performed. The present study examines the biochemical and structural characterization of a human KAT II/AADAT. Substrate screening of human KAT II revealed that the enzyme has a very broad substrate specificity, is capable of catalysing the transamination of 16 out of 24 tested amino acids and could utilize all 16 tested a-oxo acids as amino-group acceptors. Kinetic analysis of human KAT II demonstrated its catalytic efficiency for individual amino-group donors and acceptors, providing information as to its preferred substrate affinity. Structural analysis of the human KAT II complex with a-oxoglutaric acid revealed a conformational change of an N-terminal fraction, residues 15-33, that is able to adapt to different substrate sizes, which provides a structural basis for its broad substrate specificity.

  18. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci.

    Science.gov (United States)

    Peralta, Guillermo Hugo; Bergamini, Carina Viviana; Hynes, Erica Rut

    2016-01-01

    Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor. PMID:27266631

  19. Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci.

    Science.gov (United States)

    Peralta, Guillermo Hugo; Bergamini, Carina Viviana; Hynes, Erica Rut

    2016-01-01

    Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.

  20. Crystal structure of L-alanine phosphate

    International Nuclear Information System (INIS)

    The crystal structure of L-alanine phosphate (C3O2NH7 · H3PO4) is determined by the single-crystal diffraction technique; a 11.918(1) A, b = 9.117(1) A, c = 7.285(1) A, γ = 104.7(1) deg., space group P21, and Z = 4. The amino group of the alanine is protonated by the hydrogen atom of the phosphoric acid. Pairs of H2PO-4 hydrogen-bonded ions are packed into layers alternating with layers of alanine molecules in the crystal. No hydrogen bonds are formed immediately between the alanine molecules

  1. Inhibition of glutamine synthesis induces glutamate dehydrogenase-dependent ammonia fixation into alanine in co-cultures of astrocytes and neurons

    DEFF Research Database (Denmark)

    Dadsetan, Sherry; Bak, Lasse Kristoffer; Sørensen, Michael;

    2011-01-01

    study it was investigated if the glutamine synthetase (GS) inhibitor methionine sulfoximine (MSO) would enhance alanine synthesis by blocking the GS-dependent ammonia scavenging process. Hence, co-cultures of neurons and astrocytes were incubated for 2.5h with [U-(13)C]glucose to monitor de novo......It has been previously demonstrated that ammonia exposure of neurons and astrocytes in co-culture leads to net synthesis not only of glutamine but also of alanine. The latter process involves the concerted action of glutamate dehydrogenase (GDH) and alanine aminotransferase (ALAT). In the present...... synthesis of alanine and glutamine in the absence and presence of 5.0 mM NH(4)Cl and 10 mM MSO. Ammonia exposure led to increased incorporation of label but not to a significant increase in the amount of these amino acids. However, in the presence of MSO, glutamine synthesis was blocked and synthesis...

  2. Comparison of blood aminotransferase methods for assessment of myopathy and hepatopathy in Florida manatees (Trichechus manatus latirostris).

    Science.gov (United States)

    Harr, Kendal E; Allison, Kathryn; Bonde, Robert K; Murphy, David; Harvey, John W

    2008-06-01

    Muscle injury is common in Florida manatees (Trichechus manatus latirostris). Plasma aspartate aminotransferase (AST) is frequently used to assess muscular damage in capture myopathy and traumatic injury. Therefore, accurate measurement of AST and alanine aminotransferase (ALT) is important in managed, free-ranging animals, as well as in those rehabilitating from injury. Activities of these enzymes, however, are usually not increased in manatees with either acute or chronic muscle damage, despite marked increases in plasma creatine kinase activity. It is hypothesized that this absence of response is due to apoenzymes in the blood not detected by commonly used veterinary assays. Addition of coenzyme pyridoxal-5-phosphate (P5P or vitamin B6) should, therefore, result in higher measured enzyme activities. The objective of this study was to determine the most accurate, precise, and diagnostically useful method for aminotransferase measurement in manatees that can be used in veterinary practices and diagnostic laboratories. Additionally, appropriate collection and storage techniques were assessed. The use of an optimized commercial wet chemical assay with 100 micromol P5P resulted in a positive bias of measured enzyme activities in a healthy population of animals. However, AST and ALT were still much lower than that typically observed in domestic animals and should not be used alone in the assessment of capture myopathy and muscular trauma. Additionally, the dry chemistry analyzer, typically used in clinics, reported significantly higher and less precise AST and ALT activities with poor correlation to those measured with wet chemical methods found in diagnostic laboratories. Therefore, these results cannot be clinically compared. Overall, the optimized wet chemical method was the most precise and diagnostically useful measurement of aminotransferase in samples. Additionally, there was a statistically significant difference between paired serum and plasma measurement

  3. Comparison of blood aminotransferase methods for assessment of myopathy and hepatopathy in Florida manatees (Trichechus manatus latirostris).

    Science.gov (United States)

    Harr, Kendal E; Allison, Kathryn; Bonde, Robert K; Murphy, David; Harvey, John W

    2008-06-01

    Muscle injury is common in Florida manatees (Trichechus manatus latirostris). Plasma aspartate aminotransferase (AST) is frequently used to assess muscular damage in capture myopathy and traumatic injury. Therefore, accurate measurement of AST and alanine aminotransferase (ALT) is important in managed, free-ranging animals, as well as in those rehabilitating from injury. Activities of these enzymes, however, are usually not increased in manatees with either acute or chronic muscle damage, despite marked increases in plasma creatine kinase activity. It is hypothesized that this absence of response is due to apoenzymes in the blood not detected by commonly used veterinary assays. Addition of coenzyme pyridoxal-5-phosphate (P5P or vitamin B6) should, therefore, result in higher measured enzyme activities. The objective of this study was to determine the most accurate, precise, and diagnostically useful method for aminotransferase measurement in manatees that can be used in veterinary practices and diagnostic laboratories. Additionally, appropriate collection and storage techniques were assessed. The use of an optimized commercial wet chemical assay with 100 micromol P5P resulted in a positive bias of measured enzyme activities in a healthy population of animals. However, AST and ALT were still much lower than that typically observed in domestic animals and should not be used alone in the assessment of capture myopathy and muscular trauma. Additionally, the dry chemistry analyzer, typically used in clinics, reported significantly higher and less precise AST and ALT activities with poor correlation to those measured with wet chemical methods found in diagnostic laboratories. Therefore, these results cannot be clinically compared. Overall, the optimized wet chemical method was the most precise and diagnostically useful measurement of aminotransferase in samples. Additionally, there was a statistically significant difference between paired serum and plasma measurement

  4. beta-Chloro-L-alanine inhibition of the Escherichia coli alanine-valine transaminase.

    OpenAIRE

    Whalen, W A; Wang, M D; Berg, C M

    1985-01-01

    beta-Chloro-L-alanine, an amino acid analog which inhibits a number of enzymes, reversibly inhibited the Escherichia coli K-12 alanine-valine transaminase, transaminase C. This inhibition, along with the inhibition of transaminase B, accounted for the isoleucine-plus-valine requirement of E. coli in the presence of beta-chloro-L-alanine.

  5. Antiretroviral Drugs and Risk of Chronic Alanine Aminotransferase Elevation in Human Immunodeficiency Virus (HIV)-Monoinfected Persons

    DEFF Research Database (Denmark)

    Kovari, Helen; Sabin, Caroline A; Ledergerber, Bruno;

    2016-01-01

    Background.  Although human immunodeficiency virus (HIV)-positive persons on antiretroviral therapy (ART) frequently have chronic liver enzyme elevation (cLEE), the underlying cause is often unclear. Methods.  Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) Study participants without...... a consistent association between tenofovir and cLEE emerging within the first 2 years after drug initiation. This novel tenofovir-cLEE signal should be further investigated....

  6. Soluble Serum CD81 Is Elevated in Patients with Chronic Hepatitis C and Correlates with Alanine Aminotransferase Serum Activity

    Science.gov (United States)

    Welker, Martin-Walter; Reichert, David; Susser, Simone; Sarrazin, Christoph; Martinez, Yolanda; Herrmann, Eva; Zeuzem, Stefan; Piiper, Albrecht; Kronenberger, Bernd

    2012-01-01

    Aim Cellular CD81 is a well characterized hepatitis C virus (HCV) entry factor, while the relevance of soluble exosomal CD81 in HCV pathogenesis is poorly defined. We performed a case-control study to investigate whether soluble CD81 in the exosomal serum fraction is associated with HCV replication and inflammatory activity. Patients and Methods Four cohorts were investigated, patients with chronic hepatitis C (n = 37), patients with chronic HCV infection and persistently normal ALT levels (n = 24), patients with long term sustained virologic response (SVR, n = 7), and healthy volunteers (n = 23). Concentration of soluble CD81 was assessed semi-quantitatively after differential centrifugation ranging from 200 g to 100,000 g in the fifth centrifugation fraction by immunoblotting and densitometry. Results Soluble CD81 was increased in patients with chronic hepatitis C compared to healthy subjects (p = 0.03) and cured patients (p = 0.017). Patients with chronic HCV infection and persistently normal ALT levels and patients with long term SVR had similar soluble CD81 levels as healthy controls (p>0.2). Overall, soluble CD81 levels were associated with ALT levels (r = 0.334, p = 0.016) and severe liver fibrosis (p = 0.027). Conclusion CD81 is increased in the exosomal serum fraction in patients with chronic hepatitis C and appears to be associated with inflammatory activity and severity of fibrosis. PMID:22355327

  7. Late-onset primary hyperoxaluria type 1 in a Chinese individual with absent alanine:glyoxylate aminotransferase activity

    Institute of Scientific and Technical Information of China (English)

    黃炳南; 唐美華; 麥肇嘉; 盧建宜; 黃煜; 黃矩民

    2004-01-01

    @@ Nephrolithiasis is a common clinical problem, and its cause is often classified as idiopathic. Primary hyperoxaluria, mostly type 1, constitutes one of the rare causes of recurrent nephrolithiasis, but its diagnosis is often missed or delayed. The exact prevalence of primary hyperoxaluria type 1 (PH1), therefore, has been unclear. The reported prevalence varies in different countries. No Chinese PH1 has ever been reported in the literature. We report a rare case of late-onset primary hyperoxaluria, which was diagnosed only after the development of end-stage renal failure. To our knowledge, this case is the first confirmed Chinese PH1.

  8. Serum alanine aminotransferase level and response to interferon-ribavirin combination therapy in patients with chronic hepatitis C

    International Nuclear Information System (INIS)

    To determine the difference in sustained virological response to interferon-ribavirin combination therapy between patients with normal ALT and those with raised ALT in chronic hepatitis C. Patients with positive HCV RNA by PCR and compensated liver disease were included and divided in two groups. One group with ALT below upper normal limit (UNL= 65U/L) and second group with raised ALT (> 1x UNL). After treatment with standard interferon alpha 2a and ribavirin, both groups were checked for sustained viral response (SVR) six months after end of treatment and compared for response to therapy with Chi square test. Of the 70 patients included, 25 had normal ALT ( 1 x UNL). Of these, 63 patients completed treatment. Sustained viral response (SVR) was seen in 13 of 22 patients with normal ALT who completed therapy and 22 of 41 patients with raised ALT who completed treatment. Difference in SVR in two groups was not significant (p 0.679). When patients with raised ALT were sub-classified, significantly better response was seen in patients with ALT Z 2 times the upper normal limit (p 0.021). Patients with normal baseline ALT respond equally well to combination therapy as is seen in patients with raised ALT. (author)

  9. Elevated Serum Aminotransferases Secondary to Rippling Muscle Disease

    Directory of Open Access Journals (Sweden)

    Kumanan Nalankilli

    2013-05-01

    Full Text Available A 43-year-old man was referred by his general practitioner to the hepatology clinic with deranged serum aminotransferases, discovered as part of routine blood tests. The objective was to identify the cause of elevated serum aminotransferases in this patient in a systematic manner. Thorough history and physical examination revealed a background history of rippling muscle disease secondary to caveolin-3 protein deficiency, with typical clinical signs. There was a positive family history of musculoskeletal disease in the patient's father and brother. Previous diagnostic tests performed to investigate the patient's musculoskeletal symptoms, including muscle biopsies, were revisited. Subsequent systematic investigations such as blood tests, liver ultrasound scan and Fibroscan® were performed to exclude potential causes of the deranged serum aminotransferases. Liver biopsy was not performed. A consistent pattern of chronic low-grade elevations of serum aminotransferases, less than three times the upper limit of the normal range, was found. This was associated with a consistently elevated serum creatine kinase and normal renal function tests. Previous muscle biopsies had revealed chronic degenerative and regenerative changes suggestive of a focal necrotizing myopathy. Liver ultrasound scan and Fibroscan® were normal. With exclusion of other liver diseases and identification of profoundly elevated serum creatine kinase concentration, the deranged aminotransferases were attributed to rippling muscle disease.

  10. Radioimmunoassay of aspartate aminotransferase isoenzymes in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Leung, F.Y.; Niblock, A.E.; Henderson, A.R.

    1984-08-01

    A description is given of the development of a sensitive, specific radioimmunoassay for the cytoplasmic and mitochondrial isoenzymes of human aspartate aminotransferase (L-aspartate:2-oxoglutarate aminotransferase; EC 2.6.1.1). Isoenzymes from human heart tissue were purified to homogeneity and used to raise high-titer antisera in rabbits. The antisera were partly purified by selective column chromatography. The Bolton-Hunter reagent was used to radioiodinate the isoenzymes. The assay requires 100 microL of serum, includes a solid-phase second-antibody separation, and can be completed in less than 3 h. There was no cross reactivity between the two isoenzymes. As little as 5 micrograms (50 pmol) of each aspartate aminotransferase can be measured per liter of serum.

  11. Structure of putrescine aminotransferase from Escherichia coli provides insights into the substrate specificity among class III aminotransferases.

    Directory of Open Access Journals (Sweden)

    Hyung Jin Cha

    Full Text Available YgjG is a putrescine aminotransferase enzyme that transfers amino groups from compounds with terminal primary amines to compounds with an aldehyde group using pyridoxal-5'-phosphate (PLP as a cofactor. Previous biochemical data show that the enzyme prefers primary diamines, such as putrescine, over ornithine as a substrate. To better understand the enzyme's substrate specificity, crystal structures of YgjG from Escherichia coli were determined at 2.3 and 2.1 Å resolutions for the free and putrescine-bound enzymes, respectively. Sequence and structural analyses revealed that YgjG forms a dimer that adopts a class III PLP-dependent aminotransferase fold. A structural comparison between YgjG and other class III aminotransferases revealed that their structures are similar. However, YgjG has an additional N-terminal helical structure that partially contributes to a dimeric interaction with the other subunit via a helix-helix interaction. Interestingly, the YgjG substrate-binding site entrance size and charge distribution are smaller and more hydrophobic than other class III aminotransferases, which suggest that YgjG has a unique substrate binding site that could accommodate primary aliphatic diamine substrates, including putrescine. The YgjG crystal structures provide structural clues to putrescine aminotransferase substrate specificity and binding.

  12. Beta-alanine synthesis in Escherichia coli.

    OpenAIRE

    Cronan, J. E.

    1980-01-01

    The enzyme, aspartate 1-decarboxylase (L-aspartate 1-carboxy-lyase; EC 4.1.1.15), that catalyzes the reaction aspartate leads to beta-alanine + CO2 was found in extracts of Escherichia coli. panD mutants of E. coli are defective in beta-alanine biosynthesis and lack aspartate 1-decarboxylase. Therefore, the enzyme functions in the biosynthesis of the beta-alanine moiety of pantothenate. The genetic lesion in these mutants is closely linked to the other pantothenate (pan) loci of E. coli K-12.

  13. Structural analysis and mutant growth properties reveal distinctive enzymatic and cellular roles for the three major L-alanine transaminases of Escherichia coli.

    Science.gov (United States)

    Peña-Soler, Esther; Fernandez, Francisco J; López-Estepa, Miguel; Garces, Fernando; Richardson, Andrew J; Quintana, Juan F; Rudd, Kenneth E; Coll, Miquel; Vega, M Cristina

    2014-01-01

    In order to maintain proper cellular function, the metabolism of the bacterial microbiota presents several mechanisms oriented to keep a correctly balanced amino acid pool. Central components of these mechanisms are enzymes with alanine transaminase activity, pyridoxal 5'-phosphate-dependent enzymes that interconvert alanine and pyruvate, thereby allowing the precise control of alanine and glutamate concentrations, two of the most abundant amino acids in the cellular amino acid pool. Here we report the 2.11-Å crystal structure of full-length AlaA from the model organism Escherichia coli, a major bacterial alanine aminotransferase, and compare its overall structure and active site composition with detailed atomic models of two other bacterial enzymes capable of catalyzing this reaction in vivo, AlaC and valine-pyruvate aminotransferase (AvtA). Apart from a narrow entry channel to the active site, a feature of this new crystal structure is the role of an active site loop that closes in upon binding of substrate-mimicking molecules, and which has only been previously reported in a plant enzyme. Comparison of the available structures indicates that beyond superficial differences, alanine aminotransferases of diverse phylogenetic origins share a universal reaction mechanism that depends on an array of highly conserved amino acid residues and is similarly regulated by various unrelated motifs. Despite this unifying mechanism and regulation, growth competition experiments demonstrate that AlaA, AlaC and AvtA are not freely exchangeable in vivo, suggesting that their functional repertoire is not completely redundant thus providing an explanation for their independent evolutionary conservation.

  14. Incremental Predictive Value of Serum AST-to-ALT Ratio for Incident Metabolic Syndrome: The ARIRANG Study

    Science.gov (United States)

    Ahn, Song Vogue; Baik, Soon Koo; Cho, Youn zoo; Koh, Sang Baek; Huh, Ji Hye; Chang, Yoosoo; Sung, Ki-Chul; Kim, Jang Young

    2016-01-01

    Aims The ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) is of great interest as a possible novel marker of metabolic syndrome. However, longitudinal studies emphasizing the incremental predictive value of the AST-to-ALT ratio in diagnosing individuals at higher risk of developing metabolic syndrome are very scarce. Therefore, our study aimed to evaluate the AST-to-ALT ratio as an incremental predictor of new onset metabolic syndrome in a population-based cohort study. Material and Methods The population-based cohort study included 2276 adults (903 men and 1373 women) aged 40–70 years, who participated from 2005–2008 (baseline) without metabolic syndrome and were followed up from 2008–2011. Metabolic syndrome was defined according to the harmonized definition of metabolic syndrome. Serum concentrations of AST and ALT were determined by enzymatic methods. Results During an average follow-up period of 2.6-years, 395 individuals (17.4%) developed metabolic syndrome. In a multivariable adjusted model, the odds ratio (95% confidence interval) for new onset of metabolic syndrome, comparing the fourth quartile to the first quartile of the AST-to-ALT ratio, was 0.598 (0.422–0.853). The AST-to-ALT ratio also improved the area under the receiver operating characteristic curve (AUC) for predicting new cases of metabolic syndrome (0.715 vs. 0.732, P = 0.004). The net reclassification improvement of prediction models including the AST-to-ALT ratio was 0.23 (95% CI: 0.124–0.337, P<0.001), and the integrated discrimination improvement was 0.0094 (95% CI: 0.0046–0.0143, P<0.001). Conclusions The AST-to-ALT ratio independently predicted the future development of metabolic syndrome and had incremental predictive value for incident metabolic syndrome. PMID:27560931

  15. Response of Alanine Dosemeter to Heavy Ions

    Institute of Scientific and Technical Information of China (English)

    LiWenjian; SuXu; YangYingjie; YuanJianlei; DangBingrong; WangXiao; MaQiufeng; ZhouLibin; HaoJifang; MaoShuhong

    2003-01-01

    The amino acid L-α-alanine has been investigated for use as a radiation detector in low and high LET radiation fields[1]. The radiatioa detector is cheap and easy to handle. The radiation inducing free radicals are stable at normal laboratory conditions for doses below 104 Gy over a long period of time, which makes the detector useful for intercomparison and documentation purposes. The dosimetric features of alanine-based electron spin resonance (ESR) detectors in high energy electron beams used in radiotherapy were considered[2]. The 5 mm long alanine detectors were found to be the most suitable for carrying out in vivo dosimetry on patients undergoing electron beam radiotherapy. However, data concerning dosimetry of the alanine dosemeter to heavy charged particles are lacking, especially in China.

  16. Applications of alanine-based dosimetry

    International Nuclear Information System (INIS)

    Alanine-based radiation dosimetry and related dosimeters developed at the Istituto Superiore di Sanita, Rome, Italy, and capable of providing high accuracy absorbed dose determination by ESR are presented. Overall uncertainty is shown to be +-3.9% in the 10 Gy to 3 kGy range. Possible applications to radiotherapy and industry are discussed. Percentage depth dose values and dose profiles measured with alanine dosimeters in phantom are presented. (author)

  17. Serum Aminotransferases in Thai Children With Dengue Infection

    OpenAIRE

    Olarn Prommalikit; Usa Thisyakorn; Chule Thisyakorn

    2015-01-01

    Background: Hepatic manifestations are one of the unusual manifestations of dengue infection. Objectives: We conducted this study in order to study the pattern of serum aminotransferases and sequential changes before and after shock in Thai children with dengue infection. Patients and Methods: Children who were clinically and serologically diagnosed as dengue infection and were adm...

  18. Aspartate Aminotransferase - Bridging Carbohydrate and Energy Metabolism in Plasmodium Falciparum

    NARCIS (Netherlands)

    Wrenger, Carsten; Mueller, Ingrid B.; Silber, Ariel M.; Jordanova, Rositsa; Lamzin, Victor S.; Groves, Matthew R.

    2012-01-01

    In this mini-review we briefly examine and summarize evidence on the role of the plasmodial aspartate aminotransferase (AspAT) of the malarial parasite. Recent data have provided information on the products of the purine salvage pathway as well as the glycolytic and oxidative phosphorylation pathway

  19. Experiences with alanine dosimetry in afterloading brachytherapy

    International Nuclear Information System (INIS)

    At the present, the most commonly used dosimetry for radiotherapy applications are ionisation chambers and thermoluminescent dosimeters (TLD). However, there are some undesirable characteristics of these dosimetry systems, such as large detection volume (ionisation chamber) as well as fading of the radiation induced signal with time and destructive readout (TLG). The present study is an investigation into the use of the alanine/ESR dosimetry in fractionated afterloading brachytherapy during the whole radiotherapy course. There are some qualities which make alanine dosimetry attractive. These are the linear energy response, low fading under standard conditions, and the nondestructive readout. Thus the alanine dosimetry makes possible cumulative dose measurements during the radiotherapy course and an archival storage. By ionizing radiation (gamma, e, n, p, charged particles) free radicals (unpaired electrons) are produced in the amino acid alanine. The continuous wave electron spin resonance (ESR) spectroscopy is used to determine the number of free radicals, which is proportional to the absorbed dose and the alanine content of the dosimeter. The ESR measurements were made at room temperature using a Bruker EPR analyzer EMS-104. The dosimeters used in the test are alanine pellets (23.72 mg weight, 4.9 mm diameter, 1 mm height) as well as flexible alanine film dosimeters (thickness about 500 μm). The dosimeters consist of a blend of L-alpha-alanine and a binder. The alanine content of the pellets and the film dosimeters is about 88 % and 50 % by weight, respectively. The dosimeters for the calculation of the dose-effect-relationship were irradiated at the Physical-Technical Bundesanstalt in Braunschweig by a standard 60Co source. The maximum deviation from the calculated linear function is about 0.12 Gy in the dose range up to 80 Gy. The goal of medical applications was the superficial dose measurement in afterloading brachytherapy during the radiotherapy course in

  20. Alanine - ESR dosimetry, feasibility and possible applications

    International Nuclear Information System (INIS)

    Alanine ESR dosimetry presents a great interest for quality controls in radiotherapy. This new developed water equivalent alanine dosimeter allows a reproducible dose measurement, by a non-destructive readout technique in a large dose range. In this paper the stability of the dosimeter response has been shown but also its independence with the energy or the dose rate of the absorbed radiation. Through this different studies, one can broaden the application field of alanine / ESR dosimetry especially for in-vivo dosimetry. The results of the experiments and the intra operative treatment, indicate that this kind of dosimetry seems to be a promising technique for in-vivo quality controls in electron beam, γ ray or X ray radiotherapy. (authors)

  1. Biocatalytic potential of vanillin aminotransferase from Capsicum chinense

    OpenAIRE

    Weber, Nora; Ismail, Abdelrahman; Gorwa-Grauslund, Marie; Carlquist, Magnus

    2014-01-01

    Background The conversion of vanillin to vanillylamine is a key step in the biosynthetic route towards capsaicinoids in pungent cultivars of Capsicum sp. The reaction has previously been annotated to be catalysed by PAMT (putative aminotransferase; [GenBank: AAC78480.1, Swiss-Prot: O82521]), however, the enzyme has previously not been biochemically characterised in vitro. Results The biochemical activity of the transaminase was confirmed by direct measurement of the reaction with purified rec...

  2. Comparison of blood aminotransferase methods for assessment of myopathy and hepatopathy in Florida manatees (Trichechus manatus latirostris)

    Science.gov (United States)

    Harr, K.E.; Allison, K.; Bonde, R.K.; Murphy, D.; Harvey, J.W.

    2008-01-01

    Muscle injury is common in Florida manatees (Trichechus manatus latirostris). Plasma aspartate amino-transferase (AST) is frequently used to assess muscular damage in capture myopathy and traumatic injury. Therefore, accurate measurement of AST and alanine aminotransferase (ALT) is important in managed, free-ranging animals, as well as in those rehabilitating from injury. Activities of these enzymes, however, are usually not increased in manatees with either acute or chronic muscle damage, despite marked increases in plasma creatine kinase activity. It is hypothesized that this absence of response is due to apoenzymes in the blood not detected by commonly used veterinary assays. Addition of coenzyme pyridoxal-5-phosphate (P5P or vitamin B6) should, therefore, result in higher measured enzyme activities. The objective of this study was to determine the most accurate, precise, and diagnostically useful method for aminotransferase measurement in manatees that can be used in veterinary practices and diagnostic laboratories. Additionally, appropriate collection and storage techniques were assessed. The use of an optimized commercial wet chemical assay with 100 ??mol P5P resulted in a positive bias of measured enzyme activities in a healthy population of animals. However, AST and ALT were still much lower than that typically observed in domestic animals and should not be used alone in the assessment of capture myopathy and muscular trauma. Additionally, the dry chemistry analyzer, typically used in clinics, reported significantly higher and less precise AST and ALT activities with poor correlation to those measured with wet chemical methods found in diagnostic laboratories. Therefore, these results cannot be clinically compared. Overall, the optimized wet chemical method was the most precise and diagnostically useful measurement of aminotransferase in samples. Additionally, there was a statistically significant difference between paired serum and plasma measurement

  3. A study of the irradiation temperature coefficient for L-alanine and DL-alanine dosemeters

    International Nuclear Information System (INIS)

    Alanine dosimetry is now well established both as a reference and routine dosemeter for industrial irradiation processing. Accurate dosimetry under the relatively harsh conditions of industrial processing requires a characterisation of the parameters that influence the dosemeter response. The temperature of the dosemeter during irradiation is a difficult quantity to measure so that the accuracy of the temperature coefficient that governs the dosemeter response becomes a critical factor. Numerous publications have reported temperature coefficients for several types of alanine dosemeters. The observed differences in the measured values were commonly attributed to the differences in the polymer binder or the experimental design of the measurement. However, the data demonstrated a consistent difference in the temperature coefficients between L-alanine and DL-alanine. Since there were no commonalities in the dosemeter composition or the measurement methods applied, a clear conclusion is not possible. To resolve this issue, the two isomeric forms of alanine dosemeters were prepared and irradiated in an identical manner. The results indicated that the DL-alanine temperature coefficient is more than 50% higher than the L-alanine temperature coefficient. (authors)

  4. Dose Response of Alanine Detectors Irradiated with Carbon Ion Beams

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo;

    2011-01-01

    . Methods: Alanine detectors have been irradiated with carbon ions with an energy range of 89-400 MeV/u. The relative effectiveness of alanine has been measured in this regime. Pristine and spread out Bragg peak depth-dose curves have been measured with alanine dosimeters. The track-structure based alanine......Purpose: The dose response of the alanine detector shows a dependence on particle energy and type, when irradiated with ion beams. The purpose of this study is to investigate the response behaviour of the alanine detector in clinical carbon ion beams and compare the results with model predictions...... of the detector geometry implemented in the Monte Carlo simulations....

  5. Synthesis and characterization of alanine boron hydrate for its use in thermal neutron dosimetry

    International Nuclear Information System (INIS)

    Alanine boron hydrate was synthesized for its possible use as intercomparison dosimeter for thermal neutron irradiation. The irradiations were performed in the Nuclear Reactor of the Nuclear Center of Mexico. The salt was prepared by reacting alanine and boric acid in a (1:1) stoichiometric ratio in neutral pH 7.5 aqueous solution and also in a basic pH 13 solution. The latter reaction was prepared with the addition of ammonia hydroxide (25%). Solutions were stirred and afterwards were let to evaporate. The obtained product in each reaction is a white solid. Dosimeters were prepared with the obtained reaction products and irradiated under thermal neutron flux of 5 x 107 n/cm2 s. For 30 hours. The analysis of irradiated samples was made in a Variant E-15 Electron Paramagnetic Resonance spectrometer. The observed response of the samples prepared with the reaction product at the basic pH is approximately 50% higher than the neutral pH samples. In order to investigate the optimum signal enhancement samples were prepared in a basic pH medium in the following stoichiometric ratios: (1:0.5); (1:0.75); (1:1.25); (1:1.5) and (1:1.75). It was observed that the samples of the reaction (1:0.75) produced the higher response. The response was 2728% higher than the alanine only dosimeters. The reaction product was chemically characterized by X-ray diffraction, Nuclear Magnetic Resonance, Chromatography, Refractometry and Solubility tests. Results indicate that alanine boron hydrate is formed in basic media and in a stoichiometric ratio (1:0.75). The dosimetric characterization of alanine boron hydrate was performed, results are reported. It is concluded that alanine boron hydrate may be a good intercomparison dosimeter for thermal neutron irradiation. (Author)

  6. Liver fibrosis progression in HIV/hepatitis C virus coinfected patients with normal aminotransferases levels

    Directory of Open Access Journals (Sweden)

    Fábio Heleno de Lima Pace

    2012-08-01

    Full Text Available INTRODUCTION: Approximately 30% of hepatitis C virus (HCV monoinfected patients present persistently normal alanine aminotransferase (ALT levels. Most of these patients have a slow progression of liver fibrosis. Studies have demonstrated the rate of liver fibrosis progression in hepatitis C virus-human immunodeficiency virus (HCV-HIV coinfected patients is faster than in patients infected only by HCV. Few studies have evaluated the histological features of chronic hepatitis C in HIV-infected patients with normal ALT levels. METHODS: HCV-HIV coinfected patients (HCV-RNA and anti-HIV positive with known time of HCV infection (intravenous drugs users were selected. Patients with hepatitis B surface antigen (HBsAg positive or hepatitis C treatment before liver biopsy were excluded. Patients were considered to have a normal ALT levels if they had at least 3 normal determinations in the previous 6 months prior to liver biopsy. All patients were submitted to liver biopsy and METAVIR scale was used. RESULTS: Of 50 studied patients 40 (80% were males. All patients were treated with antiretroviral therapy. The ALT levels were normal in 13 (26% patients. HCV-HIV co-infected patients with normal ALT levels had presented means of the liver fibrosis stages (0.77±0.44 versus 1.86±1.38; p<0.001 periportal inflammatory activity (0.62±0.77 versus 2.24±1.35; p<0.001 and liver fibrosis progression rate (0.058±0.043 fibrosis unit/year versus 0.118±0.102 fibrosis unit/year significantly lower as compared to those with elevated ALT. CONCLUSIONS: HCV-HIV coinfected patients with persistently normal ALTs showed slower progression of liver fibrosis. In these patients the development of liver cirrhosis is improbable.

  7. Aspartate aminotransferase – key enzyme in the human systemic metabolism

    Directory of Open Access Journals (Sweden)

    Dagmara Otto-Ślusarczyk

    2016-03-01

    Full Text Available Aspartate aminotransferase is an organ - nonspecific enzyme located in many tissues of the human body where it catalyzes reversible reaction of transamination. There are two aspartate aminotransferase isoforms - cytoplasmic (AST1 and mitochondrial (AST2, that usually occur together and interact with each other metabolically. Both isoforms are homodimers containing highly conservative regions responsible for catalytic properties of enzyme. The common feature of all aspartate aminotransfeses is Lys – 259 residue covalent binding with prosthetic group - pyridoxal phosphate. The differences in the primary structure of AST isoforms determine their physico-chemical, kinetic and immunological properties. Because of the low concentration of L-aspartate (L-Asp in the blood, AST is the only enzyme, which supply of this amino acid as a substrate for many metabolic processes, such as urea cycle or purine and pyrimidine nucleotides in the liver, synthesis of L-arginine in the kidney and purine nucleotide cycle in the brain and the skeletal muscle. AST is also involved in D-aspartate production that regulates the metabolic activity at the auto-, para- and endocrine level. Aspartate aminotransferase is a part of the malate-aspartate shuttle in the myocardium, is involved in gluconeogenesis in the liver and kidney, glyceroneogenesis in the adipose tissue, and synthesis of neurotransmitters and neuro-glial pathway in the brain. Recently, the significant role of AST in glutaminolysis - normal metabolic pathway in tumor cells, was demonstrated. The article is devoted the role of AST, known primarily as a diagnostic liver enzyme, in metabolism of various human tissues and organs.

  8. Metabolic responses to dietary protein/carbohydrate ratios in zebra sea bream (Diplodus cervinus, Lowe, 1838) juveniles.

    Science.gov (United States)

    Coutinho, Filipe; Peres, Helena; Castro, Carolina; Pérez-Jiménez, Amalia; Pousão-Ferreira, Pedro; Oliva-Teles, Aires; Enes, Paula

    2016-02-01

    This study aims to evaluate the effect of diets with different protein to carbohydrate ratios (P:C) on the omnivorous zebra sea bream (Diplodus cervinus) juveniles growth performance, feed efficiency, N excretion and metabolic response of intermediary metabolism enzymes. Four isoenergetic and isolipidic diets were formulated to contain increasing protein levels (25, 35, 45 and 55%) at the expense of carbohydrates (43, 32, 21 and 9%): diets P25C43, P35C32, P45C21 and P55C9. Growth performance, feed efficiency (FE), N intake [(g kg(-1) average body weight (ABW) day(-1))], N retention (g kg(-1) ABW day(-1)) and energy retention (kJ kg(-1) ABW day(-1)) increased with the increase of P:C ratio. The best growth performance and FE were achieved with diet P45C21. Ammonia excretion (mg NH4–N kg(-1) ABW day(-1)) increased as dietary protein level increased. Alanine aminotransferase and glutamate dehydrogenase activities increased with the increase of dietary P:C ratio. The opposite was observed for malic enzyme activity. Aspartate aminotransferase, hexokinase, glucokinase, fructose-1, 6-bisphosphatase and fatty acid synthetase activities were unaffected by dietary treatments. Response of key amino acid catabolic enzymes and N excretion levels to dietary P:C ratio supports the metabolic adaptability of this species to dietary protein inclusion levels. Overall, zebra sea bream seems capable of better utilize dietary protein rather than dietary carbohydrates as energy source which may be an obstacle for using more economically diets and thus for reducing environmental N loads in semi-intensive aquaculture of this species. PMID:26480835

  9. Design and Mechanism of Tetrahydrothiophene-based GABA Aminotransferase Inactivators

    OpenAIRE

    Le, Hoang V.; Hawker, Dustin D.; Wu, Rui; Doud, Emma; Widom, Julia; Sanishvili, Ruslan; Liu, Dali; Kelleher, Neil L.; Silverman, Richard B.

    2015-01-01

    Low levels of γ-aminobutyric acid (GABA), one of two major neurotransmitters that regulate brain neuronal activity, are associated with many neurological disorders, such as epilepsy, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, and cocaine addiction. One of the main methods to raise the GABA level in human brain is to use small molecules that cross the blood-brain barrier and inhibit the activity of γ-aminobutyric acid aminotransferase (GABA-AT), the enzyme that degrades GA...

  10. Differential redox potential between the human cytosolic and mitochondrial branched-chain aminotransferase

    Institute of Scientific and Technical Information of China (English)

    Steven J. Coles; John T. Hancock; Myra E. Conway

    2012-01-01

    The human branched-chain aminotransferase (hBCAT) isoenzymes are CXXC motif redox sensitive homodimers central to glutamate metabolism in the central nervous system.These proteins respond differently to oxidation by H2O2,NO,and S-glutathionylation,suggesting that the redox potential is distinct between isoenzymes.Using various reduced to oxidized glutathione ratios (GSH:GSSG) to alter the redox environment,we demonstrate that hBCATc (cytosolic) has an overall redox potential that is 30 mV lower than hBCATm (mitochondrial).Furthermore,the CXXC motif of hBCATc was estimated to be 80 mV lower,suggesting that hBCATm is more oxidizing in nature.Western blot analysis revealed close correlations between hBCAT S-glutathionylation and the redox status of the assay environment,offering the hBCAT isoenzymes as novel biomarkers for cytosolic and mitochondrial oxidative stress.

  11. Progress in quality control of alanine dosimeters

    International Nuclear Information System (INIS)

    The ESR/alanine system has been used for different applications, over several years, as a classical routine dosimetry service. This service is based on alanine dosimeters constituted by pellets manufactured by our laboratory, which are presented with some specifications of use and different parameters bound to the intrinsic quality of the dosimeter itself. These parameters were obtained through the strict application of a production protocol and a validation protocol created, tested and validated under a quality assurance system. Every year, one batch of photon dosimeters is produced and controlled using these protocols and the specifications associated with it are checked. Two categories of data are considered separately: physical parameters and experimental data obtained by measurement on our ESR system are given with their associated standard deviation. (author)

  12. Dosimetric applications of α-alanine

    International Nuclear Information System (INIS)

    Irradiation of solid polycristalline alanine creates a free radical, whose concentration can be measured from its ESR signal. The radical CH3CradicalHCOO- of practically unlimited stability at room temperature shows an electronic absorption spectrum in the UV. Modern methods of diffuse reflectance spectrophotometry allow to measure the radical concentration, which is proportional to the absorbed dose of radiation. The alanine dosimeter is prepared in a thin layer, adequate both for the congested isodose curves in the case of accelerated electrons irradiation and the method of measurement. Thus the proposed dosimeter is applicable not only for gamma, but also for EB radiation processing in the range of 0.1 to 50 kGy. The application of the dosimeter does not demand to use the ESR spectrometer, even of the type dedicated to alanine dosimetry only, but may be performed by UV-VIS spectrophotometer equipped with an integrating sphere, permitting measurements of the Kubelka-Munk function. (author) 5 refs.; 1 fig

  13. Functional characterization of aromatic amino acid aminotransferase involved in 2-phenylethanol biosynthesis in isolated rose petal protoplasts.

    Science.gov (United States)

    Hirata, Hiroshi; Ohnishi, Toshiyuki; Ishida, Haruka; Tomida, Kensuke; Sakai, Miwa; Hara, Masakazu; Watanabe, Naoharu

    2012-03-15

    In rose flowers, 2-phenylethanol (2PE) is biosynthesized from l-phenylalanine (l-Phe) via phenylacetaldehyde (PAld) by the actions of two enzymes, pyridoxal-5'-phosphate (PLP)-dependent aromatic amino acid decarboxylase (AADC) and phenylacetaldehyde reductase (PAR). We here report that Rosa 'Yves Piaget' aromatic amino acid aminotransferase produced phenylpyruvic acid (PPA) from l-Phe in isolated petal protoplasts. We have cloned three full length cDNAs (RyAAAT1-3) of aromatic amino acid aminotransferase families based on rose EST database and homology regions. The RyAAATs enzymes were heterogeneously expressed in Escherichia coli and characterized biochemically. The recombinant RyAAAT3 showed the highest activity toward l-Phe in comparison with l-tryptophan, l-tyrosine, d-Phe, glycine, and l-alanine, and showed 9.7-fold higher activity with l-Phe rather than PPA as a substrate. RyAAAT3 had an optimal activity at pH 9 and at 45-55°C with α-ketoglutaric acid, and was found to be a PLP dependent enzyme based on the inhibition test using Carbidopa, an inhibitor of PLP-dependent enzymes. The transcript of RyAAAT3 was expressed in flowers as well as other organs of R. 'Yves Piaget'. RNAi suppression of RyAAAT3 decreased 2PE production, revealing the involvement of RyAAAT3 in 2PE biosynthesis in rose protoplasts and indicating that rose protoplasts have potentially two different 2PE biosynthetic pathways, the AADC route and the new route via PPA from l-Phe.

  14. Depth profiling of irradiated alanine-polymer pellets

    International Nuclear Information System (INIS)

    An alanine-polyethylene (PE) pellet is used as an alanine/electron spin resonance (ESR) dosimeter in radiation facilities. Using the unique depth profiling capability of Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS), the chemical structure of the alanine-PE pellet and its fading reaction after γ-ray irradiation have been studied. It was found that PE concentration of the alanine-PE pellet in a surface or near surface is larger that in a bulk. The products resulting from fading were observed in the bulk alanine-PE pellet irradiated and stored for 6 months at room temperature. (author)

  15. Combined effect of amino and carboxyl group in α-alanine on seeded precipitation of sodium aluminate solution

    Institute of Scientific and Technical Information of China (English)

    L(U) Bao-lin; CHEN Qi-yuan; YIN Zhou-lan; HU Hui-ping

    2009-01-01

    α-alanine was adopted as a new additive to elucidate the seeded precipitation mechanism of sodium aluminate solution. α-alanine has the inhibitory effect at the initial period of reaction, but the favorable effect in subsequent reaction. The combined effect of amino and carboxyl group in α-alanine was confirmed by investigating the effect of propionic acid, ethamine and the mixture of propionic acid and ethamine (mole ratio 1:1) on the precipitation of sodium aluminate solution, respectively. The inhibitory effect derives from the adsorption of amino or carboxyl group in α-alanine on the active surface sites of gibbsite, which was confirmed by the alleviating inhibitory effects of propionic acid, ethamine and α-alanine due to the double crystal seed mass. The semi-quantitative IR spectrum analysis of the relative concentrations of Al2O(OH)62- with the band at about 550 cm-1 and polynuclear aluminate ion with the bands at about 880 cm-1 and 635 cm-1, indicates that the dynamic balance among some aluminate species present in sodium aluminate solution is broken due to the addition of α-alanine, thus resulting in the change of the seeded precipitation ratio of sodium aluminate solution.

  16. Alanine flux in obese and healthy humans as evaluated by 15N- and 2H3-labeled alanines

    International Nuclear Information System (INIS)

    Estimates of plasma alanine flux as measured in humans using L-[15N]-alanine or L-[3,3,3-2H3]alanine were compared by simultaneous intravenous infusion of both tracers. Plasma isotope enrichments were measured by chemical ionization gas chromatography-mass spectrometry. In 16 obese women before and during a hypocaloric diet and in 4 normal men in the postabsorptive and fed states, the fluxes were highly correlated (r2 = 0.93) although plasma alanine flux with the 2H tracer was two to three times greater than that obtained with [15N]alanine. The fluxes decreased with the hypocaloric diet in obese subjects and increased during the fed state in healthy adults. Thus, although the estimates of alanine flux differed according to the tracer used, both appear to give equivalent information about changes in alanine kinetics induced by the nutritional conditions examined

  17. Relative response of the alanine dosimeter to medium energy x-rays

    Science.gov (United States)

    Anton, M.; Büermann, L.

    2015-08-01

    The response of the alanine dosimeter to kilovoltage x-rays with respect to the dose to water was measured, relative to the response to Co-60 radiation. Two series of x-ray qualities were investigated, one ranging from 30 kV to 100 kV tube voltage (TW series), the other one ranging from 70 kV to 280 kV (TH series). Due to the use of the water calorimeter as a primary standard, the uncertainty of the delivered dose is significantly lower than for other published data. The alanine response was measured as described in a previous publication (Anton et al 2013 Phys. Med. Biol. 58 3259-82). The uncertainty component due to the alanine measurement and analysis is ⩽0.4%, the major part of the combined uncertainty of the relative response originates from the uncertainty of the delivered dose. The relative uncertainties of the relative response vary from ⩽2% for the TW series to ⩽1.1% for the TH series. Different from the behaviour of the alanine dosimeter for megavoltage x-rays or electrons, the relative response drops significantly from unity for Co-60 radiation to less than 64% for the TW quality with a tube voltage of 30 kV. In order to reproduce this behaviour through Monte Carlo simulations, not only the ratio of the absorbed dose to alanine to the absorbed dose to water has to be known, but also the intrinsic efficiency, i.e. the dependence of the number of free radicals generated per unit of absorbed dose on the photon energy. This quantity is not yet accessible for the TW series. For a possible use of the alanine dosimeter for kilovoltage x-rays, for example in electronic brachytherapy, users should rely on the measured data for the relative response which have become available with this publication.

  18. Relative response of the alanine dosimeter to medium energy x-rays

    International Nuclear Information System (INIS)

    The response of the alanine dosimeter to kilovoltage x-rays with respect to the dose to water was measured, relative to the response to Co-60 radiation.Two series of x-ray qualities were investigated, one ranging from 30 kV to 100 kV tube voltage (TW series), the other one ranging from 70 kV to 280 kV (TH series). Due to the use of the water calorimeter as a primary standard, the uncertainty of the delivered dose is significantly lower than for other published data. The alanine response was measured as described in a previous publication (Anton et al 2013 Phys. Med. Biol. 58 3259–82). The uncertainty component due to the alanine measurement and analysis is ⩽0.4%, the major part of the combined uncertainty of the relative response originates from the uncertainty of the delivered dose. The relative uncertainties of the relative response vary from ⩽2% for the TW series to ⩽1.1% for the TH series.Different from the behaviour of the alanine dosimeter for megavoltage x-rays or electrons, the relative response drops significantly from unity for Co-60 radiation to less than 64% for the TW quality with a tube voltage of 30 kV. In order to reproduce this behaviour through Monte Carlo simulations, not only the ratio of the absorbed dose to alanine to the absorbed dose to water has to be known, but also the intrinsic efficiency, i.e. the dependence of the number of free radicals generated per unit of absorbed dose on the photon energy. This quantity is not yet accessible for the TW series.For a possible use of the alanine dosimeter for kilovoltage x-rays, for example in electronic brachytherapy, users should rely on the measured data for the relative response which have become available with this publication. (paper)

  19. Relative response of the alanine dosimeter to medium energy x-rays.

    Science.gov (United States)

    Anton, M; Büermann, L

    2015-08-01

    The response of the alanine dosimeter to kilovoltage x-rays with respect to the dose to water was measured, relative to the response to Co-60 radiation.Two series of x-ray qualities were investigated, one ranging from 30 kV to 100 kV tube voltage (TW series), the other one ranging from 70 kV to 280 kV (TH series). Due to the use of the water calorimeter as a primary standard, the uncertainty of the delivered dose is significantly lower than for other published data. The alanine response was measured as described in a previous publication (Anton et al 2013 Phys. Med. Biol. 58 3259-82). The uncertainty component due to the alanine measurement and analysis is ⩽0.4%, the major part of the combined uncertainty of the relative response originates from the uncertainty of the delivered dose. The relative uncertainties of the relative response vary from ⩽2% for the TW series to ⩽1.1% for the TH series.Different from the behaviour of the alanine dosimeter for megavoltage x-rays or electrons, the relative response drops significantly from unity for Co-60 radiation to less than 64% for the TW quality with a tube voltage of 30 kV. In order to reproduce this behaviour through Monte Carlo simulations, not only the ratio of the absorbed dose to alanine to the absorbed dose to water has to be known, but also the intrinsic efficiency, i.e. the dependence of the number of free radicals generated per unit of absorbed dose on the photon energy. This quantity is not yet accessible for the TW series.For a possible use of the alanine dosimeter for kilovoltage x-rays, for example in electronic brachytherapy, users should rely on the measured data for the relative response which have become available with this publication.

  20. Crystallization and preliminary crystallographic analysis of d-alanine-d-alanine ligase from Streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yong-Zhi; Sheng, Yu [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Li, Lan-Fen [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Tang, De-Wei [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Liu, Xiang-Yu [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Zhao, Xiaojun, E-mail: zhaoxj@scu.edu.cn [Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China); Liang, Yu-He, E-mail: zhaoxj@scu.edu.cn; Su, Xiao-Dong [National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871 (China); Institute for Nanobiomedical Technology and Membrane Biology, West China Hospital, Sichuan University, Chengdu 610065, Sichuan (China)

    2007-09-01

    A potential target for antibiotic drug design, d-alanine-d-alanine ligase from S. mutans, was expressed in E. coli, purified and crystallized. Diffraction data were collected to 2.4 Å resolution. d-Alanine-d-alanine ligase is encoded by the gene ddl (SMU-599) in Streptococcus mutans. This ligase plays a very important role in cell-wall biosynthesis and may be a potential target for drug design. To study the structure and function of this ligase, the gene ddl was amplified from S. mutans genomic DNA and cloned into the expression vector pET28a. The protein was expressed in soluble form in Escherichia coli strain BL21 (DE3). Homogeneous protein was obtained using a two-step procedure consisting of Ni{sup 2+}-chelating and size-exclusion chromatography. Purified protein was crystallized and the cube-shaped crystal diffracted to 2.4 Å. The crystal belongs to space group P3{sub 1}21 or P3{sub 2}21, with unit-cell parameters a = b = 79.50, c = 108.97 Å. There is one molecule per asymmetric unit.

  1. Effect of Arsenic and Chromium on the Serum Amino-Transferases Activity in Indian Major Carp, Labeo rohita

    Directory of Open Access Journals (Sweden)

    Anjaneyulu Yerramilli

    2007-09-01

    Full Text Available Arsenic and hexavalent chromium toxicity results from their ability to interact with sulfahydryl groups of proteins and enzymes, and to substitute phosphorus in a variety of biochemical reactions. Alanine aminotransferase (ALT; E.C: 2.6.1.2 and Aspartate amino transferase (AST; EC 2.6.1.1 play a crucial role in transamination reactions and can be used as potential biomarkers to indicate hepatotoxicity and cellular damage. While histopathological studies in liver tissue require more time and expertise, simple and reliable biochemical analysis of ALT and AST can be used for a rapid assessment of tissue and cellular damage within 96 h. The main objective of this study was to determine the acute effects of arsenic and hexavalent chromium on the activity of ALT and AST in the Indian major carp, Labeo rohita for 24 h and 96 h. Significant increase in the activity of ALT (P < 0.01 from controls in arsenic exposed fish indicates serious hepatic damage and distress condition to the fish. However, no such significant changes were observed in chromium-exposed fish suggesting that arsenic is more toxic to the fish. These findings indicate that ALT and AST are candidate biomarkers for arsenic-induced hepatotoxicity in Labeo rohita.

  2. International society of sports nutrition position stand: Beta-Alanine.

    Science.gov (United States)

    Trexler, Eric T; Smith-Ryan, Abbie E; Stout, Jeffrey R; Hoffman, Jay R; Wilborn, Colin D; Sale, Craig; Kreider, Richard B; Jäger, Ralf; Earnest, Conrad P; Bannock, Laurent; Campbell, Bill; Kalman, Douglas; Ziegenfuss, Tim N; Antonio, Jose

    2015-01-01

    The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of beta-alanine supplementation. Based on the current available literature, the conclusions of the ISSN are as follows: 1) Four weeks of beta-alanine supplementation (4-6 g daily) significantly augments muscle carnosine concentrations, thereby acting as an intracellular pH buffer; 2) Beta-alanine supplementation currently appears to be safe in healthy populations at recommended doses; 3) The only reported side effect is paraesthesia (tingling), but studies indicate this can be attenuated by using divided lower doses (1.6 g) or using a sustained-release formula; 4) Daily supplementation with 4 to 6 g of beta-alanine for at least 2 to 4 weeks has been shown to improve exercise performance, with more pronounced effects in open end-point tasks/time trials lasting 1 to 4 min in duration; 5) Beta-alanine attenuates neuromuscular fatigue, particularly in older subjects, and preliminary evidence indicates that beta-alanine may improve tactical performance; 6) Combining beta-alanine with other single or multi-ingredient supplements may be advantageous when supplementation of beta-alanine is high enough (4-6 g daily) and long enough (minimum 4 weeks); 7) More research is needed to determine the effects of beta-alanine on strength, endurance performance beyond 25 min in duration, and other health-related benefits associated with carnosine. PMID:26175657

  3. Purification and preliminary crystallization of alanine racemase from Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Im Hookang

    2007-05-01

    Full Text Available Abstract Background Over the past fifteen years, antibiotic resistance in the Gram-positive opportunistic human pathogen Streptococcus pneumoniae has significantly increased. Clinical isolates from patients with community-acquired pneumonia or otitis media often display resistance to two or more antibiotics. Given the need for new therapeutics, we intend to investigate enzymes of cell wall biosynthesis as novel drug targets. Alanine racemase, a ubiquitous enzyme among bacteria and absent in humans, provides the essential cell wall precursor, D-alanine, which forms part of the tetrapeptide crosslinking the peptidoglycan layer. Results The alanine racemases gene from S. pneumoniae (alrSP was amplified by PCR and cloned and expressed in Escherichia coli. The 367 amino acid, 39854 Da dimeric enzyme was purified to electrophoretic homogeneity and preliminary crystals were obtained. Racemic activity was demonstrated through complementation of an alr auxotroph of E. coli growing on L-alanine. In an alanine racemases photometric assay, specific activities of 87.0 and 84.8 U mg-1 were determined for the conversion of D- to L-alanine and L- to D-alanine, respectively. Conclusion We have isolated and characterized the alanine racemase gene from the opportunistic human pathogen S. pneumoniae. The enzyme shows sufficient homology with other alanine racemases to allow its integration into our ongoing structure-based drug design project.

  4. Potential energy surface of alanine polypeptide chains

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Yakubovich, Alexander V.; Solov'yov, Andrey V.;

    2006-01-01

    The multidimensional potential energy surfaces of the peptide chains consisting of three and six alanine (Ala) residues have been studied with respect to the degrees of freedom related to the twist of these molecules relative to the peptide backbone (these degrees of freedom are responsible...... for the folding of such peptide molecules and proteins). The potential energy surfaces have been calculated ab initio within the framework of the density functional theory taking into account all electrons in the system. The probabilities of transitions between various stable conformations of polypeptide...... molecules are evaluated. The results are compared to the data obtained by molecular dynamics simulations and to the available experimental data. The influence of the secondary structure of the polypeptide chain on its conformational properties with respect to rotations has been studied. It is shown that...

  5. Dosimetry by ESR spectroscopy of alanine

    International Nuclear Information System (INIS)

    Dosimetry based on electron spin resonance analysis of radiation-induced free radicals in amino acids (e.g. L-alanine) is relevant to biological dosimetry applications. Typical features are a wide dose range covering more than 5 decades (1-105Gy), energy independent response for photons above 100 keV, long-term stability of the ESR signal, and fast straightforward readout technique. Typical dosimeter samples, consisting of small pellets of microcrystalline amino acids in paraffin, are rugged, non-toxic, and insensitive to surface contaminations. Moreover, they are prepared homogeneously and inexpensively in large batches and can be evaluated repeatedly and supply archival dosimetry data. They have proven to be highly useful in various applications of radiation processing and sterilization dosimetry, food irradiation, quality control, radiation dosimetry, radiation therapy measurements, and as a reference system for dosimetry mailing intercomparisons. (author)

  6. K-band EPR dosimetry: small-field beam profile determination with miniature alanine dosimeter

    International Nuclear Information System (INIS)

    The use of small-size alanine dosimeters presents a challenge because the signal intensity is less than the spectrometer sensitivity. K-band (24 GHz) EPR spectrometer seems to be a good compromise between size and sensitivity of the sample. Miniature alanine pellets were evaluated for small-field radiation dosimetry. Dosimeters of DL-alanine/PVC with dimensions of 1.5 mm diameter and 2.5 mm length with 5 mg mass were developed. These dosimeters were irradiated with 10 MV X-rays in the dose range 0.05-60 Gy and the first harmonic (1 h) spectra were recorded. Microwave power, frequency and amplitude of modulation were optimized to obtain the best signal-to-noise ratio (S/N). For beam profile determination, a group of 25 dosimeters were placed in an acrylic device with dimensions of (7.5x2.5x1) cm3 and irradiated with a (3x3) cm2 10 MV X-rays beam field size. The dose at the central region of the beam was 20 Gy at a depth of 2.2 cm (build up for acrylic). The acrylic device was oriented perpendicular to the beam axis and to the gantry rotation axis. For the purposes of comparison of the spatial resolution, the beam profile was also determined with a radiographic film and 2 mm aperture optical densitometer; in this case the dose was 1 cGy. The results showed a similar spatial resolution for both types of dosimeters. The dispersion in dose reading was larger for alanine in comparison with the film, but alanine dosimeters can be read faster and more directly than film over a wide dose range

  7. Tyrosine aminotransferase: biochemical and structural properties and molecular dynamics simulations

    Energy Technology Data Exchange (ETDEWEB)

    Mehere, P.; Robinson, H.; Han, Q.; Lemkul, J. A.; Vavricka, C. J.; Bevan, D. R.; Li, J.

    2010-11-01

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using {alpha}-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 {angstrom} resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  8. Tyrosine Aminotransferase: Biochemical and Structural Properties and Molecular Dynamics Simulations

    Energy Technology Data Exchange (ETDEWEB)

    P Mehere; Q Han; J Lemkul; C Vavricka; H Robinson; D Bevan; J Li

    2011-12-31

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using {alpha}-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 {angstrom} resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  9. Biochemical and Structural Properties of Mouse Kynurenine Aminotransferase III

    Energy Technology Data Exchange (ETDEWEB)

    Han, Q.; Robinson, H; Cai, T; Tagle, D; Li, J

    2009-01-01

    Kynurenine aminotransferase III (KAT III) has been considered to be involved in the production of mammalian brain kynurenic acid (KYNA), which plays an important role in protecting neurons from overstimulation by excitatory neurotransmitters. The enzyme was identified based on its high sequence identity with mammalian KAT I, but its activity toward kynurenine and its structural characteristics have not been established. In this study, the biochemical and structural properties of mouse KAT III (mKAT III) were determined. Specifically, mKAT III cDNA was amplified from a mouse brain cDNA library, and its recombinant protein was expressed in an insect cell protein expression system. We established that mKAT III is able to efficiently catalyze the transamination of kynurenine to KYNA and has optimum activity at relatively basic conditions of around pH 9.0 and at relatively high temperatures of 50 to 60C. In addition, mKAT III is active toward a number of other amino acids. Its activity toward kynurenine is significantly decreased in the presence of methionine, histidine, glutamine, leucine, cysteine, and 3-hydroxykynurenine. Through macromolecular crystallography, we determined the mKAT III crystal structure and its structures in complex with kynurenine and glutamine. Structural analysis revealed the overall architecture of mKAT III and its cofactor binding site and active center residues. This is the first report concerning the biochemical characteristics and crystal structures of KAT III enzymes and provides a basis toward understanding the overall physiological role of mammalian KAT III in vivo and insight into regulating the levels of endogenous KYNA through modulation of the enzyme in the mouse brain.

  10. Tyrosine aminotransferase: biochemical and structural properties and molecular dynamics simulations.

    Science.gov (United States)

    Mehere, Prajwalini; Han, Qian; Lemkul, Justin A; Vavricka, Christopher J; Robinson, Howard; Bevan, David R; Li, Jianyong

    2010-11-01

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine and other aromatic amino acids. The enzyme is thought to play a role in tyrosinemia type II, hepatitis and hepatic carcinoma recovery. The objective of this study is to investigate its biochemical and structural characteristics and substrate specificity in order to provide insight regarding its involvement in these diseases. Mouse TAT (mTAT) was cloned from a mouse cDNA library, and its recombinant protein was produced using Escherichia coli cells and purified using various chromatographic techniques. The recombinant mTAT is able to catalyze the transamination of tyrosine using α-ketoglutaric acid as an amino group acceptor at neutral pH. The enzyme also can use glutamate and phenylalanine as amino group donors and p-hydroxy-phenylpyruvate, phenylpyruvate and alpha-ketocaproic acid as amino group acceptors. Through macromolecular crystallography we have determined the mTAT crystal structure at 2.9 Å resolution. The crystal structure revealed the interaction between the pyridoxal-5'-phosphate cofactor and the enzyme, as well as the formation of a disulphide bond. The detection of disulphide bond provides some rational explanation regarding previously observed TAT inactivation under oxidative conditions and reactivation of the inactive TAT in the presence of a reducing agent. Molecular dynamics simulations using the crystal structures of Trypanosoma cruzi TAT and human TAT provided further insight regarding the substrate-enzyme interactions and substrate specificity. The biochemical and structural properties of TAT and the binding of its cofactor and the substrate may help in elucidation of the mechanism of TAT inhibition and activation.

  11. Comparison of EPR response of alanine and Gd₂O₃-alanine dosimeters exposed to TRIGA Mainz reactor.

    Science.gov (United States)

    Marrale, M; Schmitz, T; Gallo, S; Hampel, G; Longo, A; Panzeca, S; Tranchina, L

    2015-12-01

    In this work we report some preliminary results regarding the analysis of electron paramagnetic resonance (EPR) response of alanine pellets and alanine pellets added with gadolinium used for dosimetry at the TRIGA research reactor in Mainz, Germany. Two set-ups were evaluated: irradiation inside PMMA phantom and irradiation inside boric acid phantom. We observed that the presence of Gd2O3 inside alanine pellets increases the EPR signal by a factor of 3.45 and 1.24 in case of PMMA and boric acid phantoms, respectively. We can conclude that in the case of neutron beam with a predominant thermal neutron component the addition of gadolinium oxide can significantly improve neutron sensitivity of alanine pellets. Monte Carlo (MC) simulations of both response of alanine and Gd-added alanine pellets with FLUKA code were performed and a good agreement was achieved for pure alanine dosimeters. For Gd2O3-alanine deviations between MC simulations and experimental data were observed and discussed. PMID:26315099

  12. Properties of human liver cytosolic aspartate aminotransferase mRNAs generated by alternative polyadenylation site selection

    International Nuclear Information System (INIS)

    Human cytosolic aspartate aminotransferase (cAspAT) cDNA clones have been isolated from an adult human liver cDNA library. Among the clones, two cDNAs of 1,550 and 1,950 base pairs, respectively, have been characterized. These two cDNAs differ only in the lengths of their 3' noncoding regions and by the presence of one or two putative polyadenylation signals AATAAA. Northern blot analysis revealed two different mRNAs of 2.1 and 1.8 kbp in several human tissues, whereas Southern blot analysis suggested the existence of a single gene for the human cAspAT. The two mRNA species result from the alternative use of two polyadenylation signals. In the liver, the relative ratio of these mRNAs varies among different species and, in humans at least, during development. The properties of the two mRNAs were compared. The half-lives of the 2.1 and 1.8 kbp mRNAs, in the HepG2 cell line, are 8 and 12 h, respectively. The two mRNAs have similar and rather short poly(A) tracts of 20-50 nucleotides. Both mRNAs are capable of directing the in vitro synthesis of the cAspAT protein. The authors conclude that both the 2.1 and 1.8 kbp cAspAT mRNAs are functional and exhibit similar properties

  13. Elevated alanine aminotransferase activity is not associated with dyslipidemias, but related to insulin resistance and higher disease grades in non-diabetic non-alcoholic fatty liver disease

    Directory of Open Access Journals (Sweden)

    Mohammad Ebrahim Ghamar-Chehreh

    2012-09-01

    Conclusions: This study shows that the associations of increased ALT serum levels in NAFLD patients are different from what are supposed before. By excluding diabetic patients from our population, we find that increased ALT levels are not associated with dyslipidemias but are independently associated with insulin resistance and NAFLD grading on ultrasonographic evaluations. Further studies are needed to confirm our results.

  14. Absolute quantification of serum microRNA-122 and its correlation with liver inflammation grade and serum alanine aminotransferase in chronic hepatitis C patients

    Directory of Open Access Journals (Sweden)

    Jiang-hua Wang

    2015-01-01

    Conclusions: The present study showed that serum microRNA-122 was elevated in acute and chronic hepatitis patients. However, this biomarker for acute liver injury did not reflect the liver inflammation activity in CHC patients.

  15. ELEVATED ALANINE AMINOTRANSFERASE (ALT IN BLOOD DONORS: AN ASSESSMENT OF THE MAIN ASSOCIATED CONDITIONS AND ITS RELATIONSHIP TO THE DEVELOPMENT OF HEPATITIS C

    Directory of Open Access Journals (Sweden)

    Fernando Lopes GONÇALES Jr.

    1998-07-01

    Full Text Available The determination of aminotranferases levels is very useful in the diagnosis of hepatopathies. In recent years, an elevated serum ALT level in blood donors has been associated with an increased risk of post-transfusion hepatitis (PTH. The purpose of the study was to research the factors associated with elevated ALT levels in a cohort of voluntary blood donors and to evaluate the relationship between increased ALT levels and the development of hepatitis C (HCV infection. 166 volunteer blood donors with elevated ALT at the time of their first donation were studied. All of the donors were questioned about previous hepatopathies, exposure to hepatitis, exposure to chemicals, use of medication or drugs, sexual behaviour, contact with blood or secretions and their intake of alcohol. Every three months, the serum levels of AST, ALT, alkaline phosphatase, gamma glutamyl transpeptidase, cholesterol, triglyceride and glycemia are assessed over a two year follow-up. The serum thyroid hormone levels as well as the presence of auto-antibodies were also measured. Abdominal ultrasound was performed in all patients with persistently elevated ALT or AST levels. A needle biopsy of liver was performed in 9 donors without definite diagnostic after medical investigation. The presence of anti-HCV antibodies in 116 donors were assayed again the first clinical evaluation. At the end of follow-up period (2 years later 71 donors were tested again for the presence of anti-HCV antibodies. None of donors resulted positive for hepatitis B or hepatitis C markers during the follow-up. Of the 116 donors, 101 (87% had persistently elevated ALT serum levels during the follow-up. Obesity and alcoholism were the principal conditions related to elevated ALT serum levels in 91/101 (90.1% donors. Hypertriglyceridemia, hypercholesterolemia, hypothyroidism and diabetes mellitus also were associated with increased ALT levels. Only 1/101 (0.9% had mild chronic active non A-G viral hepatitis and 3/101 (2.9% had liver biopsy with non-specific reactive hepatitis. The determination of ALT levels was not useful to detect donors infected with HCV at donation in Brazil, including the initial seronegative anti-HCV phase.A determinação dos níveis de alanina aminostransferase (ALT tem sido útil para o diagnóstico de hepatopatias. Ultimamente, a elevação dos níveis séricos de ALT em doadores de sangue, tem sido associada a um maior risco de hepatites pós-transfusionais. Este estudo busca identificar os fatores associados com elevados níveis de ALT entre doadores voluntários de sangue e avaliar as relações entre estes aumentos de ALT e o desenvolvimento de infecção pelo vírus da hepatite C. Assim, 116 doadores voluntários de sangue com níveis de ALT elevados, quando da primeira doação, foram estudados. Todos foram questionados sobre hepatopatias prévias, exposição a hepatites, exposição a produtos químicos, uso de drogas ou medicamentos, comportamento sexual, contacto com sangue ou secreções e consumo de álcool. A cada 3 meses foram medidos os níveis de AST, ALT, fosfatase alcalina, gama-glutamil transferase, colesterol, triglicérides e glicemia durante o período de 1-2 anos. Os níveis séricos de hormônios tireoidianos e a presença de auto-anticorpos também foram mensurados. Ultrassonografia abdominal foi realizada em todos os pacientes com elevação persistente dos níveis de AST ou ALT. Foi realizada biópsia hepática em 9 doadores sem diagnóstico definido após investigação clínica. A presença de anticorpos anti-HCV foi novamente pesquisada em 116 doadores no momento da primeira avaliação clínica. Ao final do follow-up (2 anos 71 doadores foram re-testados para a presença do anti-HCV. Nenhum doador se tornou reagente para os marcadores dos virus da hepatite B ou hepatite C, durante o seguimento. Dos 116 doadores, 101 (87% mantiveram níveis séricos de ALT persistentemente aumentados. Obesidade e alcoolismo foram as principais condições associadas à elevação dos níveis séricos de ALT em 91/101 (90,1% doadores. Hipertrigliceridemia, hipercolesterolemia, hipotireoidismo e diabetes mellitus também se associaram a níveis aumentados de ALT. Somente 1/101 (0,9% apresentou hepatite crônica ativa não A-G e 3/101 (2,9% apresentaram biópsia hepática com diagnóstico de hepatite reacional. A determinação rotineira dos níveis de ALT, em bancos de sangue não foi útil para detectar doadores infectados com o vírus da hepatite C no Brasil no período que antecede a soroconversão para anti-vhc.

  16. Structural, spectral, thermal, dielectric, mechanical and optical properties of urea L-alanine acetate single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Jaikumar, D. [Department of Physics, Voorhees College, Vellore, Tamil Nadu, 632001 (India); Kalainathan, S., E-mail: kalainathan@yahoo.co [Physics Division, SAS, VIT University, Vellore, Tamil Nadu, 632014 (India); Bhagavannarayana, G. [CGC section, National Physical Laboratory, New Delhi, 110012 (India)

    2010-05-15

    A new organic nonlinear optical crystal, urea L-alanine acetate (ULAA) has been grown by solution growth using slow cooling technique with the vision to improve the properties of the L-alanine crystals. Urea and L-alanine material were mixed in the molar ratio 1:4. Solubility and metastable zone width were determined. Single crystal XRD analyses revealed that the crystal lattice of ULAA is orthorhombic system, primitive lattice with cell parameters a=5.7971 A, b=6.0391 A, c=12.3276 A with space group P2{sub 1}2{sub 1}2{sub 1} (D{sub 2}{sup 4}). High-resolution X-ray diffraction (HR-XRD) analysis was carried out to study their crystalline perfection. FTIR spectrum was recorded to identify the presence of functional groups and molecular structure was confirmed by {sup 1}H NMR spectrum. From the mass spectrum, the ratio of compound formation of ULAA was analyzed. Thermal strength of the grown crystal has been studied using thermo-gravimetric (TG) and differential thermal analysis (DTA). Dielectric measurements reveal that the grown crystals have very low dielectric loss. The mechanical behavior was studied by Vickers microhardness test. The grown crystals were found to be transparent in the entire visible region. Preliminary measurement using Kurtz powder technique with Nd-YAG laser light of wavelength 1064 nm indicates that their second harmonic generation (SHG) efficiency is roughly equal to that of pure KDP.

  17. Structural studies of the catalytic reaction pathway of a hyperthermophilic histidinol-phosphate aminotransferase

    OpenAIRE

    Fernandez, F.J. (Francisco J.); Vega, M C; Lehmann, F; Sandmeier, E; Gehring, H; Christen, P; Wilmanns, M.

    2004-01-01

    In histidine biosynthesis, histidinol-phosphate aminotransferase catalyzes the transfer of the amino group from glutamate to imidazole acetol-phosphate producing 2-oxoglutarate and histidinol phosphate. In some organisms such as the hyperthermophile Thermotoga maritima, specific tyrosine and aromatic amino acid transaminases have not been identified to date, suggesting an additional role for histidinol-phosphate aminotransferase in other transamination reactions generating aromatic amino acid...

  18. Alanine synthesis from glyceraldehyde and ammonium ion in aqueous solution

    Science.gov (United States)

    Weber, A. L.

    1985-01-01

    The formation of alanine (ala) form C(14)-glyceraldehyde and ammonium phosphate in the presence or absence of a thiol is reported. At ambient temperature, ala synthesis was six times more rapid in the presence of 3-mercaptopropionic acid than in its absence (0.6 and 0.1 percent, respectively, after 60 days). Similarly, the presence of another thiol, N-acetylcysteinate, increased the production of ala, as well as of lactate. The reaction pathway of thiol-catalyzed synthesis of ala, with the lactic acid formed in a bypath, is suggested. In this, dehydration of glyceraldehyde is followed by the formation of hemithioacetal. In the presence of ammonia, an imine is formed, which eventually yields ala. This pathway is consistent with the observation that the rate ratio of ala/lactate remains constant throughout the process. The fact that the reaction takes place under anaerobic conditions in the presence of H2O and with the low concentrations of simple substrates and catalysts makes it an attractive model prebiotic reaction in the process of molecular evolution.

  19. Medical reference dosimetry using EPR measurements of alanine

    DEFF Research Database (Denmark)

    Helt-Hansen, Jakob; Rosendal, F.; Kofoed, I.M.;

    2009-01-01

    Background. Electron spin resonance (EPR) is used to determine the absorbed dose of alanine dosimeters exposed to clinical photon beams in a solid-water phantom. Alanine is potentially suitable for medical reference dosimetry, because of its near water equivalence over a wide energy spectrum, low...... methods the proposed algorithm can be applied without normalisation of phase shifts caused by changes in the g-value of the cavity. The study shows that alanine dosimetry is a suitable candidate for medical reference dosimetry especially for quality control applications....

  20. Alanine EPR dosimeter response in proton therapy beams

    International Nuclear Information System (INIS)

    We report a series of measurements directed to assess the suitability of alanine as a mailable dosimeter for dosimetry quality assurance of proton radiation therapy beams. These measurements include dose-response of alanine at 140 MeV, and comparison of response vs energy with a parallel plate ionization chamber. All irradiations were made at the Harvard Cyclotron Laboratory, and the dosimeters were read at NIST. The results encourage us that alanine could be expected to serve as a mailable dosimeter with systematic error due to differential energy response no greater than 3% when doses of 25 Gy are used. (Author)

  1. The antiproton depth–dose curve measured with alanine detectors

    CERN Document Server

    Bassler, Niels; Palmans, Hugo; Holzscheiter, Michael H; Kovacevic, Sandra

    2008-01-01

    n this paper we report on the measurement of the antiproton depth–dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen and Olsen for conversion of calculated dose into response. A good agreement is observed between the measured and calculated relative effectiveness although an underestimation of the measured values beyond the Bragg-peak remains unexplained. The model prediction of response of alanine towards heavy charged particles encourages future use of the alanine detectors for dosimetry of mixed radiation fields.

  2. Colorimetry method for estimation of glycine, alanine and isoleucine

    Directory of Open Access Journals (Sweden)

    Shah S

    2007-01-01

    Full Text Available A simple and sensitive colorimetry method has been developed for estimation of amino acids glycine, alanine and isoleucine. Amino acids were derivatized with dichlone in presence of sodium bicarbonate. Amino acids showed maximum absorbance at 470 nm. The method was validated in terms of linearity (5-25 µg/ml for glycine, alanine and isoleucine, precision (intra-day variation 0.13-0.78, 0.22-1.29, 0.58-2.52% and inter-day variation 0.52-2.49, 0.43-3.12, 0.58- 4.48% for glycine, alanine and isoleucine respectively, accuracy (91.43-98.86, 96.26-105.99 and 95.73-104.82 for glycine, alanine and isoleucine respectively, limit of detection (0.6, 1 and 1 µg/ml for glycine, alanine and isoleucine respectively and limit of quantification (5 µg/ml for glycine, alanine and isoleucine. The method was found to be simple and sensitive.

  3. Selfcalibrated alanine/EPR dosimeters. A new generation of solid state/EPR dosimeters

    International Nuclear Information System (INIS)

    Alanine/EPR dosimeters are well established as secondary, reference dosimeters for high-energy radiation. However, there are various sources of uncertainty in the evaluation of absorbed dose. This arises primarily from the necessity to calibrate each EPR spectrometer and each batch of dosimeters before their use. In order to overcome this disadvantage, a new generation alanine/EPR dosimeter has been developed, and its possibilities as a radiation detector are reported. Principally, it is a mixture of alanine, some quantity of EPR active substance, and a binding material. The EPR active substance, acting as an internal EPR standard, is chosen to have EPR parameters which are independent of the irradiation dose. The simultaneous recording of the spectra of both the sample and the standard under the same experimental conditions and the estimation of the ratio Ialanine/IMn as a function of the absorbed dose strongly reduces the uncertainties. The response of these dosimeters for 60Co γ-radiation exhibits excellent linearity and reproducibility in the range of absorbed dose, 102 - 5 x 104 Gy. (author)

  4. Expression of an L-alanine dehydrogenase gene in Zymomonas mobilis and excretion of L-alanine

    Energy Technology Data Exchange (ETDEWEB)

    Uhlenbusch, I.; Sahm, H.; Sprenger, G.A. (Inst. fur Biotechnologie 1, Julich (Germany))

    1991-05-01

    Gene alaD for L-alanine dehydrogenase from Bacillus sphaericus was cloned and introduced into Z. mobilis. Under the control of the strong promoter of the pyruvate decarboxylase (pdc) gene, the enzyme was expressed up to a specific activity of nearly 1 {mu}mol {center dot} min{sup {minus}1} {center dot} mg of protein{sup {minus}1} in recombinant cells. As a result of this high L-alanine dehydrogenase activity, growing cells excreted up to 10 mmol of alanine per 280 mmol of glucose utilized into a mineral salts medium. By the addition of 85 mM NH{sub 4}{sup +} to the medium, growth of the recombinant cells stopped, and up to 41 mmol of alanine was secreted. As alanine dehydrogenase competed with pyruvate decarboxylase (PDC) for the same substrate (pyruvate), PDC activity was reduced by starvation for the essential PDC cofactor thiamine PP{sub i}. A thiamine auxotrophy mutant of Z. mobilis which carried the alaD gene was starved for 40 h in glucose-supplemented mineral salts medium and then shifted to mineral salts medium with 85 mM NH {sub 4}{sup +} and 280 mmol of glucose. The recombinants excreted up to 84 mmol of alanine over 25 h. Alanine excretion proceeded at an initial velocity of 238 nmol {center dot} min{sup {minus}1} {center dot} mg(dry weight){sup {minus}1}. Despite this high activity, the excretion rate seemed to be a limiting factor, as the intracellular concentration of alanine was as high as 260 mM at the beginning of the excretion phase and decreased to 80 to 90 mM over 24 h.

  5. Structure of D-alanine-D-alanine ligase from Yersinia pestis: nucleotide phosphate recognition by the serine loop.

    Science.gov (United States)

    Tran, Huyen Thi; Hong, Myoung Ki; Ngo, Ho Phuong Thuy; Huynh, Kim Hung; Ahn, Yeh Jin; Wang, Zhong; Kang, Lin Woo

    2016-01-01

    D-Alanyl-D-alanine is an essential precursor of bacterial peptidoglycan and is synthesized by D-alanine-D-alanine ligase (DDL) with hydrolysis of ATP; this reaction makes DDL an important drug target for the development of antibacterial agents. Five crystal structures of DDL from Yersinia pestis (YpDDL) were determined at 1.7-2.5 Å resolution: apo, AMP-bound, ADP-bound, adenosine 5'-(β,γ-imido)triphosphate-bound, and D-alanyl-D-alanine- and ADP-bound structures. YpDDL consists of three domains, in which four loops, loop 1, loop 2 (the serine loop), loop 3 (the ω-loop) and loop 4, constitute the binding sites for two D-alanine molecules and one ATP molecule. Some of them, especially the serine loop and the ω-loop, show flexible conformations, and the serine loop is mainly responsible for the conformational change in substrate nucleotide phosphates. Enzyme-kinetics assays were carried out for both the D-alanine and ATP substrates and a substrate-binding mechanism was proposed for YpDDL involving conformational changes of the loops.

  6. EPR/alanine dosimetry for two therapeutic proton beams

    Science.gov (United States)

    Marrale, Maurizio; Carlino, Antonio; Gallo, Salvatore; Longo, Anna; Panzeca, Salvatore; Bolsi, Alessandra; Hrbacek, Jan; Lomax, Tony

    2016-02-01

    In this work the analysis of the electron paramagnetic resonance (EPR) response of alanine pellets exposed to two different clinical proton beams employed for radiotherapy is performed. One beam is characterized by a passive delivery technique and is dedicated to the eyes treatment (OPTIS2 beam line). Alanine pellets were irradiated with a 70 MeV proton beam corresponding to 35 mm range in eye tissue. We investigated how collimators with different sizes and shape used to conform the dose to the planned target volume influence the delivered dose. For this purpose we performed measurements with varying the collimator size (Output Factor) and the results were compared with those obtained with other dosimetric techniques (such as Markus chamber and diode detector). This analysis showed that the dosimeter response is independent of collimator diameter if this is larger than or equal to 10 mm. The other beam is characterized by an active spot-scanning technique, the Gantry1 beam line (maximum energy 230 MeV), and is used to treat deep-seated tumors. The dose linearity of alanine response in the clinical dose range was tested and the alanine dose response at selected locations in depth was measured and compared with the TPS planned dose in a quasi-clinical scenario. The alanine response was found to be linear in the dose in the clinical explored range (from 10 to 70 Gy). Furthermore, a depth dose profile in a quasi-clinical scenario was measured and compared to the dose computed by the Treatment Planning System PSIPLAN. The comparison of calibrated proton alanine measurements and TPS dose shows a difference under 1% in the SOBP and a "quenching" effect up to 4% in the distal part of SOBP. The positive dosimetric characteristics of the alanine pellets confirm the feasibility to use these detectors for "in vivo" dosimetry in clinical proton beams.

  7. Accumulation of D- vs. L-isomers of alanine and leucine in rat prostatic adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Conti, P.S.; Schmall, B.; Bigler, R.E.; Zanzonico, P.B.; Kleinert, E.; Whitmore, W.F. Jr.

    1985-05-01

    It has been reported that tumor tissue may accumulate some D-amino acids preferentially over the L-isomers. In order to investigate the potential use of carbon-11 labeled amino acid isomers for in vivo tumor studies with positron emission tomography in patients, the tissue distributions of alanine and leucine, substrates for the A-type and L-type amino acid transport systems, respectively, were studied in Copenhagen rates bearing the Dunning R3327G prostatic adenocarcinoma. The authors have previously reported differences in the accumulation of A-type vs. L-type amino acids in rat prostatic adenocarcinoma and normal tissues. All compounds were labeled with C-14 in the carboxyl position with specific activities of 30.0-56.6 mCi/mmol. Higher levels of C-14 activity (Relative Concentration (RC)=dpm found per gm tissue + dpm inject per gm animal mass) were observed in tumor tissue using D-alanine (0.71) compared to L- (0.21) or DL-alanine (0.27) at 45 min post-injection. While tumor/prostate and tumor/liver ratios were above 2 for all three substrates, tumor/blood and tumor/muscle were above one for only the D-isomer. Comparisons made with D-, L-, and DL-leucine also demonstrated a higher level of RC in tumor tissue with the D-isomer (0.84) vs. the L-(0.66) and DL-leucine (0.63). In this case, however, tumor/blood, tumor/prostate, and tumor/muscle ratios were above one for all three substrates, while tumor/liver ratios were below one. These results support the observation of a preferential accumulation of D-amino acids in tumor tissue over the natural L-isomers. Observed differences in the accumulation of the isomers in normal tissues are discussed.

  8. Biochemical properties and crystal structure of a β-phenylalanine aminotransferase from Variovorax paradoxus.

    Science.gov (United States)

    Crismaru, Ciprian G; Wybenga, Gjalt G; Szymanski, Wiktor; Wijma, Hein J; Wu, Bian; Bartsch, Sebastian; de Wildeman, Stefaan; Poelarends, Gerrit J; Feringa, Ben L; Dijkstra, Bauke W; Janssen, Dick B

    2013-01-01

    By selective enrichment, we isolated a bacterium that can use β-phenylalanine as a sole nitrogen source. It was identified by 16S rRNA gene sequencing as a strain of Variovorax paradoxus. Enzyme assays revealed an aminotransferase activity. Partial genome sequencing and screening of a cosmid DNA library resulted in the identification of a 1,302-bp aminotransferase gene, which encodes a 46,416-Da protein. The gene was cloned and overexpressed in Escherichia coli. The recombinant enzyme was purified and showed a specific activity of 17.5 U mg(-1) for (S)-β-phenylalanine at 30°C and 33 U mg(-1) at the optimum temperature of 55°C. The β-specific aminotransferase exhibits a broad substrate range, accepting ortho-, meta-, and para-substituted β-phenylalanine derivatives as amino donors and 2-oxoglutarate and pyruvate as amino acceptors. The enzyme is highly enantioselective toward (S)-β-phenylalanine (enantioselectivity [E], >100) and derivatives thereof with different substituents on the phenyl ring, allowing the kinetic resolution of various racemic β-amino acids to yield (R)-β-amino acids with >95% enantiomeric excess (ee). The crystal structures of the holoenzyme and of the enzyme in complex with the inhibitor 2-aminooxyacetate revealed structural similarity to the β-phenylalanine aminotransferase from Mesorhizobium sp. strain LUK. The crystal structure was used to rationalize the stereo- and regioselectivity of V. paradoxus aminotransferase and to define a sequence motif with which new aromatic β-amino acid-converting aminotransferases may be identified.

  9. Biochemical and Structural Characterization of a Ureidoglycine Aminotransferase in the Klebsiella pneumoniae Uric Acid Catabolic Pathway

    Energy Technology Data Exchange (ETDEWEB)

    French, Jarrod B.; Ealick, Steven E. (Cornell)

    2010-09-03

    Many plants, fungi, and bacteria catabolize allantoin as a mechanism for nitrogen assimilation. Recent reports have shown that in plants and some bacteria the product of hydrolysis of allantoin by allantoinase is the unstable intermediate ureidoglycine. While this molecule can spontaneously decay, genetic analysis of some bacterial genomes indicates that an aminotransferase may be present in the pathway. Here we present evidence that Klebsiella pneumoniae HpxJ is an aminotransferase that preferentially converts ureidoglycine and an {alpha}-keto acid into oxalurate and the corresponding amino acid. We determined the crystal structure of HpxJ, allowing us to present an explanation for substrate specificity.

  10. Effects of dose fractionation on the response of alanine dosimetry

    International Nuclear Information System (INIS)

    Alanine dosimetry is well established as a transfer standard and is becoming more prevalently used in routine dosimetry systems for radiation processing. Many routine measurement applications in radiation processing involve absorbed dose measurements resulting from fractioned exposures to ionizing radiation. Fractioning of absorbed dose is identified as an influence quantity (ISO/ASTM, 2013). This paper reports on study results of absorbed dose fractioning characteristics of alanine for gamma and high energy electron beam radiation sources. The results of this study indicate a radiation response difference due to absorbed dose fractioning in response can be observed after four fractionations for high-energy electron beams and no difference up to seven fractions for gamma rays using an ANOVA evaluation method. - Highlights: • Fractioning effects signaled in electron beam using an ANOVA at 6 equal increments. • Fractioning effects not signaled in gamma using an ANOVA up to 7 equal increments. • Insensitivity of alanine to dose fractioning indicates nominal impact on calibration

  11. Morphosynthesis of alanine mesocrystals by pH control.

    Science.gov (United States)

    Ma, Yurong; Cölfen, Helmut; Antonietti, Markus

    2006-06-01

    Crystallization of DL-alanine is studied as a single polymorph model case to analyze the different modes of crystallization of polar organic molecules in absence of any structure directing additives. Depending on supersaturation, which is controlled either by temperature or by pH, and in the absence of additives, crystallization by mesoscale assembly of nanoparticles is found over a wide range of conditions, leading to so-called mesocrystals. This supplements the classical molecule-based crystallization mechanism, which is identified at lower supersaturations and at pH values away from the isoelectric point (IEP). The resulting alanine crystals are characterized by SEM, XRD, and single-crystal analysis. Time-resolved conductivity measurements and dynamic light scattering of the reaction solutions reveal information about precursor structures and reaction kinetics. A formation mechanism is proposed for the alanine mesocrystals. PMID:16771332

  12. Alanine dosimeter for practical use using polyethylene as binder

    Energy Technology Data Exchange (ETDEWEB)

    Tateishi, Tsuneo (Japan Radioisotope Association, Tokyo (Japan)); Kobayashi, Toshikazu; Iso, Katsuaki; Sone, Yasuhiro; Mamuro, Tetsuo

    1992-02-01

    Alanine dosimeters were manufactured using polyethylene as a binder and their characteristics were studied with the intention of developing cheap dosimeter for practical routine use having high precision in a dose range of 0.1-100 kGy. The effects of temperature and humidity during storage after irradiation on fading of the ESR response, which is proportional to radiation-induced free radicals in alanine, and the influence of ESR measurement conditions on the ESR response were investigated in detail. As the results, it was confirmed that practical dosimetry of satisfactorily high precision is possible with the manufactured dosimeters by following appropriate measurement procedures. (author).

  13. Alanine dosimeter for practical use using polyethylene as binder

    International Nuclear Information System (INIS)

    Alanine dosimeters were manufactured using polyethylene as a binder and their characteristics were studied with the intention of developing cheap dosimeter for practical routine use having high precision in a dose range of 0.1-100 kGy. The effects of temperature and humidity during storage after irradiation on fading of the ESR response, which is proportional to radiation-induced free radicals in alanine, and the influence of ESR measurement conditions on the ESR response were investigated in detail. As the results, it was confirmed that practical dosimetry of satisfactorily high precision is possible with the manufactured dosimeters by following appropriate measurement procedures. (author)

  14. Identification and Partial Characterization of an L-Tyrosine Aminotransferase (TAT from Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Pranav R. Prabhu

    2010-01-01

    Full Text Available The aminotransferase gene family in the model plant Arabidopsis thaliana consists of 44 genes. Twenty six of these enzymes are classified as characterized meaning that the reaction(s that the enzyme catalyzes are documented using experimental means. The remaining 18 enzymes are uncharacterized and are therefore deemed putative. Our laboratory is interested in elucidating the function(s of the remaining putative aminotransferase enzymes. To this end, we have identified and partially characterized an aminotransferase (TAT enzyme from Arabidopsis annotated by the locus tag At5g36160. The full-length cDNA was cloned and the purified recombinant enzyme was characterized using in vitro and in vivo experiments. In vitro analysis showed that the enzyme is capable of interconverting L-Tyrosine and 4-hydroxyphenylpyruvate, and L-Phenylalanine and phenylpyruvate. In vivo analysis by functional complementation showed that the gene was able to complement an E. coli with a background of aminotransferase mutations that confers auxotrophy for L-Tyrosine and L-Phenylalanine.

  15. Structural Determinants of the beta-Selectivity of a Bacterial Aminotransferase

    NARCIS (Netherlands)

    Wybenga, Gjalt G.; Crismaru, Ciprian G.; Janssen, Dick B.; Dijkstra, Bauke W.

    2012-01-01

    Chiral beta-amino acids occur as constituents of various natural and synthetic compounds with potentially useful bioactivities. The pyridoxal 5'-phosphate (PLP)-dependent S-selective transaminase from Mesorhizobium sp. strain LUK (MesAT) is a fold type I aminotransferase that can be used for the pre

  16. Biochemical Properties and Crystal Structure of a β-Phenylalanine Aminotransferase from Variovorax paradoxus

    NARCIS (Netherlands)

    Crismaru, Ciprian G.; Wybenga, Gjalt G.; Szymanski, Wiktor; Wijma, Hein J.; Wu, Bian; Bartsch, Sebastian; de Wildeman, Stefaan; Poelarends, Gerrit J.; Feringa, Ben L.; Dijkstra, Bauke; Janssen, Dick B.

    2013-01-01

    By selective enrichment, we isolated a bacterium that can use beta-phenylalanine as a sole nitrogen source. It was identified by 16S rRNA gene sequencing as a strain of Variovorax paradoxus. Enzyme assays revealed an aminotransferase activity. Partial genome sequencing and screening of a cosmid DNA

  17. Parvovirus B19-Induced Constellation of Acute Renal Failure, Elevated Aminotransferases and Congestive Heart Failure

    Directory of Open Access Journals (Sweden)

    Iain W McAuley

    1997-01-01

    Full Text Available This report details a case of acute renal failure and elevated aminotransferases with subsequent development of congestive heart failure in a patient with history of exposure to parvovirus B19 and serological evidence of acute infection with this agent. This constellation of organ involvement has not been previously reported in the literature.

  18. Structure Expression and Function of kynurenine Aminotransferases in Human and Rodent Brains

    Energy Technology Data Exchange (ETDEWEB)

    Q Han; T Cai; D Tagle; J Li

    2011-12-31

    Kynurenine aminotransferases (KATs) catalyze the synthesis of kynurenic acid (KYNA), an endogenous antagonist of N-methyl-D: -aspartate and alpha 7-nicotinic acetylcholine receptors. Abnormal KYNA levels in human brains are implicated in the pathophysiology of schizophrenia, Alzheimer's disease, and other neurological disorders. Four KATs have been reported in mammalian brains, KAT I/glutamine transaminase K/cysteine conjugate beta-lyase 1, KAT II/aminoadipate aminotransferase, KAT III/cysteine conjugate beta-lyase 2, and KAT IV/glutamic-oxaloacetic transaminase 2/mitochondrial aspartate aminotransferase. KAT II has a striking tertiary structure in N-terminal part and forms a new subgroup in fold type I aminotransferases, which has been classified as subgroup Iepsilon. Knowledge regarding KATs is vast and complex; therefore, this review is focused on recent important progress of their gene characterization, physiological and biochemical function, and structural properties. The biochemical differences of four KATs, specific enzyme activity assays, and the structural insights into the mechanism of catalysis and inhibition of these enzymes are discussed.

  19. Intrahepatic and peripheral T-cell responses in genotype 1b hepatitis C virus-infected patients with persistently normal and elevated aminotransferase levels

    Institute of Scientific and Technical Information of China (English)

    Filiz Akyüz; Nuray Polat; Sabahattin Kaymakoglu; Nevzat Aksoy; Kadir Demir; Fatih Be(s)i(s)ik; Selim Badur; Yilmaz (C)akaloglu; Atilla (O)kten

    2005-01-01

    AIM: To evaluate whether the cytokine responses in liver and serum differ in chronic hepatitis C patients with normal and high alanine aminotransferase (ALT) levels.METHODS: Thirty-three (16 with normal ALT level as group 1 and 17 with elevated ALT level as group 2) patients infected with genotype 1b hepatitis C virus (HCV) were examined. Liver infiltrating lymphomononuclear cells (LILMCs) were isolated from liver biopsy by collagenase type 1 and stimulated with phytohemagglutinin and interleukin 2 (IL-2). IL-10, IL-12,interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) were determined in serum and LILMCs by ELISA.RESULTS: Serum cytokine levels were similar in both groups (P>0.05). Stimulated IFN-γ and TNF-α levels in LILMCs were increased in both groups. IL-12 and IL-10levels stimulated with IL-2 were higher in group 1 than in group 2 (P = 0.023). Histological activity index (HAI)and stage had a negative correlation with TNF-α and IFN-γ levels in group 2.CONCLUSION: Increased T-helper type 2 (Th2)cytokine response may regress inflammatory and biochemical activity. Progression of histological abnormalities in persons with elevated ALT probably depends on insufficient Th2 cytokine response, which does not balance Th1 cytokine response.

  20. A stereo-inverting D-phenylglycine aminotransferase from Pseudomonas stutzeri ST-201: purification, characterization and application for D-phenylglycine synthesis.

    Science.gov (United States)

    Wiyakrutta, S; Meevootisom, V

    1997-07-01

    D-phenylglycine aminotransferase (D-PhgAT) from a newly isolated soil bacterium, Pseudomonas stutzeri ST-201, was purified to electrophoretic homogeneity and characterized. The molecular weight (M(r)) of the native enzyme was estimated to be 92,000. It is composed of two subunits identical in molecular weight (M(r)) = 47,500). The isoelectric point (pI) of the native enzyme was 5.0. The enzyme catalyzed reversible transamination specific for D-phenylglycine or D-4-hydroxyphenylglycine in which 2-oxoglutarate was an exclusive amino group acceptor and was converted into L-glutamic acid. Neither the D- nor L-isomer of phenylalanine, tyrosine, alanine, valine, leucine, isoleucine or serine could serve as a substrate. The enzyme was most active at alkaline pH with maximum activity at pH 9-10. The temperature for maximum activity was 35-45 degrees C. The apparent K(m) values for D-phenylglycine and for 2-oxoglutarate at 35 degrees C, pH 9.5 were 1.1 and 2.4 mM, respectively. The enzyme activity was strongly inhibited by typical inhibitors of pyridoxal phosphate-dependent enzymes. Possible application of this enzyme for synthesis of enantiomerically pure D-phenylglycine was demonstrated. PMID:9249994

  1. Preparation of 15N-labeled L-alanine by coupling the alanine dehydrogenase and alcohol dehydrogenase reactions

    International Nuclear Information System (INIS)

    A simple enzymatic procedure for the preparation of L-[15N]alanine, one of the metabolically most active amino acids in all types of cells, is reported. The procedure is based on the coupling of two reactions, one catalyzed by bacterial alanine dehydrogenase, the second catalyzed by yeast alcohol dehydrogenase. An impediment in the use of this procedure could be the high cost of commercial AlaDH. However, the enzyme is widespread in the Bacillus species and partially purified samples, adequate preparative purposes, could be obtained relatively easily by chromatography on blue-Sepharose. (Auth.)

  2. The narrow substrate specificity of human tyrosine aminotransferase--the enzyme deficient in tyrosinemia type II.

    Science.gov (United States)

    Sivaraman, Sharada; Kirsch, Jack F

    2006-05-01

    Human tyrosine aminotransferase (hTATase) is the pyridoxal phosphate-dependent enzyme that catalyzes the reversible transamination of tyrosine to p-hydrophenylpyruvate, an important step in tyrosine metabolism. hTATase deficiency is implicated in the rare metabolic disorder, tyrosinemia type II. This enzyme is a member of the poorly characterized Igamma subfamily of the family I aminotransferases. The full length and truncated forms of recombinant hTATase were expressed in Escherichia coli, and purified to homogeneity. The pH-dependent titration of wild-type reveals a spectrum characteristic of family I aminotransferases with an aldimine pK(a) of 7.22. I249A mutant hTATase exhibits an unusual spectrum with a similar aldimine pK(a) (6.85). hTATase has very narrow substrate specificity with the highest enzymatic activity for the Tyr/alpha-ketoglutarate substrate pair, which gives a steady state k(cat) value of 83 s(-1). In contrast there is no detectable transamination of aspartate or other cosubstrates. The present findings show that hTATase is the only known aminotransferase that discriminates significantly between Tyr and Phe: the k(cat)/K(m) value for Tyr is about four orders of magnitude greater than that for Phe. A comparison of substrate specificities of representative Ialpha and Igamma aminotransferases is described along with the physiological significance of the discrimination between Tyr and Phe by hTATase as applied to the understanding of the molecular basis of phenylketonuria.

  3. The Antiproton Depth Dose Curve Measured with Alanine Detectors

    DEFF Research Database (Denmark)

    Bassler, Niels; Hansen, Johnny Witterseh; Palmans, Hugo;

    2008-01-01

    In this paper we report on the measurement of the antiproton depth dose curve, with alanine detectors. The results are compared with simulations using the particle energy spectrum calculated by FLUKA, and using the track structure model of Hansen et Olsen for conversion of calculated dose...

  4. Pressure-induced phase transformations in L-alanine crystals

    DEFF Research Database (Denmark)

    Olsen, J. Staun; Gerward, Leif; Freire, P.T.C.;

    2008-01-01

    Raman scattering and synchrotron X-ray diffraction have been used to investigate the high-pressure behavior of L-alanine. This study has confirmed a structural phase transition observed by Raman scattering at 2.3 GPa and identified it as a change from orthorhombic to tetragonal structure. Another...

  5. Beta-alanine supplementation in high-intensity exercise.

    Science.gov (United States)

    Harris, Roger C; Sale, Craig

    2012-01-01

    Glycolysis involves the oxidation of two neutral hydroxyl groups on each glycosyl (or glucosyl) unit metabolised, yielding two carboxylic acid groups. During low-intensity exercise these, along with the remainder of the carbon skeleton, are further oxidised to CO(2) and water. But during high-intensity exercise a major portion (and where blood flow is impaired, then most) is accumulated as lactate anions and H(+). The accumulation of H(+) has deleterious effects on muscle function, ultimately impairing force production and contributing to fatigue. Regulation of intracellular pH is achieved over time by export of H(+) out of the muscle, although physicochemical buffers in the muscle provide the first line of defence against H(+) accumulation. In order to be effective during high-intensity exercise, buffers need to be present in high concentrations in muscle and have pK(a)s within the intracellular exercise pH transit range. Carnosine (β-alanyl-L-histidine) is ideal for this role given that it occurs in millimolar concentrations within the skeletal muscle and has a pK(a) of 6.83. Carnosine is a cytoplasmic dipeptide formed by bonding histidine and β-alanine in a reaction catalysed by carnosine synthase, although it is the availability of β-alanine, obtained in small amounts from hepatic synthesis and potentially in greater amounts from the diet that is limiting to synthesis. Increasing muscle carnosine through increased dietary intake of β-alanine will increase the intracellular buffering capacity, which in turn might be expected to increase high-intensity exercise capacity and performance where this is pH limited. In this study we review the role of muscle carnosine as an H(+) buffer, the regulation of muscle carnosine by β-alanine, and the available evidence relating to the effects of β-alanine supplementation on muscle carnosine synthesis and the subsequent effects of this on high-intensity exercise capacity and performance. PMID:23075550

  6. Relationship of creatine kinase, aspartate aminotransferase, lactate dehydrogenase, and proteinuria to cardiomyopathy in the owl monkey (Aotus vociferans)

    Energy Technology Data Exchange (ETDEWEB)

    Gozalo, Alfonso S.; Chavera, Alfonso; Montoya, Enrique J.; Takano, Juan; Weller, Richard E.

    2008-02-01

    The purpose of this study was to determine serum reference values for crea- tine kinase (CK), aspartate aminotransferase (AST), and lactate dehydroge- nase (LDH) in captive-born and wild-caught owl monkeys to assess their usefulness for diagnosing myocardial disease. Urine samples were also collected and semi-quantitative tests performed. There was no statistically significant difference between CK, AST, and LDH when comparing both groups. However, when comparing monkeys with proteinuria to those without proteinuria, a statistically significant difference in CK value was observed (P = 0.021). In addition, the CK/AST ratio revealed that 29% of the animals included in this study had values suggesting cardiac infarction. Grossly, cardiac concentric hypertrophy of the left ventricle and small, pitted kidneys were the most common findings. Microscopically, myocardial fibrosis, contraction band necrosis, hypertrophy and hyperplasia of coronary arteries, medium-sized renal arteries, and afferent glomerular arteriolae were the most significant lesions, along with increased mesangial matrix and hypercellularity of glomeruli, Bowman’s capsule, and peritubular space fibroplasia. These findings suggest that CK, AST, and LDH along with urinalysis provide a reliable method for diagnosing cardiomyopathies in the owl monkey. In addition, CK/AST ratio, proteinuria, and the observed histological and ultrastructural changes suggest that Aotus vociferans suffer from arterial hypertension and chronic myocardial infarction.

  7. Experimental determination of the energy response of alanine pellets in the high dose rate 192Ir spectrum

    Science.gov (United States)

    Schaeken, B.; Cuypers, R.; Goossens, J.; Van den Weyngaert, D.; Verellen, D.

    2011-10-01

    An experimental determination of the energy correction factor for alanine/paraffin pellets in the 192Ir spectrum at varying distances from the source is presented. Alanine dosimeters were irradiated in water under full scatter conditions with a high dose rate (HDR) 192Ir source (Flexisource), using a dedicated holder. Up to six line sources (catheters) fit in a regular pattern at fixed radial distances from the holder axis, the alanine detector being placed at the centre of the holder. The HDR source was stepping every 0.5 cm within a trocar needle within ± 3.0 cm around the medial plane through the detector in order to achieve dose homogeneity within the detector volume. The energy correction factor of alanine/paraffin pellets in 192Ir relative to 60Co was experimentally determined as the inverse ratio of the dose to water measured in water around the 192Ir source to the dose to water calculated in water using the TG-43 formalism. The pellets were read out with a Bruker EMXmicro spectrometer (X-band). The amplitude of the central line in the alanine absorption spectrum from pellets irradiated within the 192Ir spectrum was directly compared with the amplitude from 60Co-irradiated pellets. The energy correction factors of Harwell pellets irradiated in the 192Ir spectrum are 1.029 ± 0.02, 1.027 ± 0.02 and 1.045 ± 0.02 at a mean weighted source-detector distance of 2.0, 2.9 and 5.3 cm, respectively. The experimentally obtained values for the energy response are 1.3% lower compared to the theoretical values for radial distances smaller than 3 cm.

  8. Role of the Aspartate Transaminase and Platelet Ratio Index in Assessing Hepatic Fibrosis and Liver Inflammation in Adolescent Patients with HBeAg-Positive Chronic Hepatitis B

    Directory of Open Access Journals (Sweden)

    Yu Zhijian

    2015-01-01

    Full Text Available This study described an index of aspartate aminotransferase-to-platelet ratio index (APRI to assess hepatic fibrosis with limited expense and widespread availability compared to the liver biopsy in adolescent patients with CHB.

  9. Formation of simple biomolecules from alanine in ocean by impacts

    Science.gov (United States)

    Umeda, Y.; Sekine, T.; Furukawa, Y.; Kakegawa, T.; Kobayashi, T.

    2013-12-01

    The biomolecules on the Earth are thought either to have originated from the extraterrestrial parts carried with flying meteorites or to have been formed from the inorganic materials on the Earth through given energy. From the standpoint to address the importance of impact energy, it is required to simulate experimentally the chemical reactions during impacts, because violent impacts may have occurred 3.8-4.0 Gyr ago to create biomolecules initially. It has been demonstrated that shock reactions among ocean (H2O), atmospheric nitrogen, and meteoritic constitution (Fe) can induce locally reduction environment to form simple bioorganic molecules such as ammonia and amino acid (Nakazawa et al., 2005; Furukawa et al., 2009). We need to know possible processes for alanine how chemical reactions proceed during repeated impacts and how complicated biomolecules are formed. Alanine can be formed from glycine (Umeda et al., in preparation). In this study, we carried out shock recovery experiments at pressures of 4.4-5.7 GPa to investigate the chemical reactions of alanine. Experiments were carried out with a propellant gun. Stainless steel containers (30 mm in diameter, 30 mm long) with 13C-labeled alanine aqueous solution immersed in olivine or hematite powders were used as targets. Air gap was present in the sample room (18 mm in diameter, 2 mm thick) behind the sample. The powder, solution, and air represent meteorite, ocean, and atmosphere on early Earth, respectively. Two powders of olivine and hematite help to keep the oxygen fugacity low and high during experiments, respectively in order to investigate the effect of oxygen fugacity on chemical processes of alanine. The recovered containers, after cleaned completely, were immersed into liquid nitrogen to freeze sample solution and then we drilled on the impact surface to extract water-soluble run products using pure water. Thus obtained products were analyzed by LC/MS for four amino acids (glycine, alanine, valine, and

  10. The effects of beam quality on EPR spectra and alanine dosimetry in mixed radiation fields

    International Nuclear Information System (INIS)

    Sensitization of L-Alanine dosimetry to neutrons showed that variations in the beam quality, resulting from adding boric acid to L-Alanine samples, affected the intensity and the shape of the lines in the EPR spectra of alanine following irradiation with thermal neutrons. Disintegration of 10B in the (n, α) process, enhances the EPR signal due to increase in the local dose deposition. The relative effectiveness of alanine dosimetry to neutrons was found to be about 0.5. (author)

  11. A study of the composite character of the ESR spectrum of alanine

    International Nuclear Information System (INIS)

    Both L and DL-alanine ESR powder spectra have been studied in the dose range of 1-106 Gy. By using Maximum Likelihood Common Factor Analysis (MLCFA), it has been demonstrated that the ESR spectrum of L-alanine is at least 3-fold composite over the whole dose range considered. For DL-alanine, in certain dose ranges only two ESR components could be detected. Possible consequences for the application and optimization of alanine dosimetry are discussed. (Author)

  12. Fibroscan Compared to FIB-4, APRI, and AST/ALT Ratio for Assessment of Liver Fibrosis in Saudi Patients With Nonalcoholic Fatty Liver Disease

    Science.gov (United States)

    Fallatah, Hind I.; Akbar, Hisham O.; Fallatah, Alyaa M.

    2016-01-01

    Background Nonalcoholic fatty liver disease (NAFLD) is being increasingly recognized as a cause of chronic liver disease. It has also been associated with devastating outcomes such as decompensated liver cirrhosis and hepatocellular carcinoma, as well as diabetes and metabolic syndrome. Objectives This study was conducted in order to assess liver fibrosis using Fibroscan, and to compare these results to the use of Fibrosis-4 (FIB-4) scores, AST platelet ratio index (APRI scores), and the AST/ALT ratios on NAFLD patients. Patients and Methods A cross sectional study was conducted on NAFLD patients who underwent Fibroscan examinations between September 1, 2011 and June 30, 2014. Demographic data was collected, including sex, age, and nationality; serum alanine aminotransferase levels (ALT, 30 - 65 U/L), serum aspartate aminotransferase levels (AST, 15 - 37 U/L), and platelet counts (150 - 400 k/μL) were also determined. The stages of fibrosis (F0 1 - 6, F1 6.1 - 7, F2 7 - 9, F3 9.1 - 10.3, and F4 ≥ 10.4) were defined in kPa. For each patient, the AST/ALT ratio was also measured. The results of APRI and FIB-4 were compared with the Fibroscan fibrosis scores. Results The results of 122 patients were analyzed, including 65 (53.3%) males with a mean age of 50.2 years (SD: 13.7; range: 18 - 86). The males were significantly younger than the females (48.7 years (SD: 16.03) versus 51.8 years (SD: 10.3 P = 0.05), respectively). The mean stiffness score was 12.02 (SD: 12.7) kPa. Forty-four patients (36%) had advanced fibrosis. The mean platelet and serum ALT levels were normal. There was a significant positive correlation between the Fibroscan results and the AST/ALT ratios, the APRI scores, and the FIB-4 results. Similarly, there was a significant positive correlation between age and fibrosis score, and a significant negative correlation between platelet count and stiffness score. Conclusions The data showed that more than one-third of the cohort exhibited advanced

  13. Induction of tyrosine aminotransferase mRNA by glucocorticoids and cAMP in fetal rat liver.

    OpenAIRE

    Ruiz-Bravo, N; Ernest, M J

    1982-01-01

    Tyrosine aminotransferase (L-tyrosine:2-oxoglutarate aminotransferase, EC 2.6.1.5) enzyme and mRNA activity were not detectable in day 20 fetal rat liver. Precocious induction of catalytic activity by in utero injection of dibutyryl cAMP was a direct consequence of the de novo appearance of translatable tyrosine aminotransferase mRNA. In contrast, in utero injection of hydrocortisone acetate failed to elicit fetal liver enzyme activity. This failure was due to the inability of the steroid hor...

  14. Characterization of the different spectral forms of glutamate 1-semialdehyde aminotransferase by mass spectrometry

    DEFF Research Database (Denmark)

    Brody, S; Andersen, Jens S.; Kannangara, C G;

    1995-01-01

    Glutamate 1-semialdehyde aminotransferase produces delta-aminolevulinate for the synthesis of chlorophyll, heme, and other tetrapyrrole pigments. The native enzyme from Synechococcus is pale yellow and has absorption maxima at 338 and 418 nm from vitamin B6. Yellow, colorless, and pink forms of t...... reduction. Acetylenic GABA attached covalently to the enzyme produced an additional mass peak, 123-126 mass units higher, in the electrospray ionization spectrum.(ABSTRACT TRUNCATED AT 250 WORDS)...

  15. Strain relief at the active site of phosphoserine aminotransferase induced by radiation damage

    OpenAIRE

    Dubnovitsky, Anatoly P.; Ravelli, Raimond B. G.; Popov, Alexander N.; Papageorgiou, Anastassios C.

    2005-01-01

    The X-ray susceptibility of the lysine-pyridoxal-5′-phosphate Schiff base in Bacillus alcalophilus phosphoserine aminotransferase has been investigated using crystallographic data collected at 100 K to 1.3 Å resolution, complemented by on-line spectroscopic studies. X-rays induce deprotonation of the internal aldimine, changes in the Schiff base conformation, displacement of the cofactor molecule, and disruption of the Schiff base linkage between pyridoxal-5′-phosphate and the Lys residue. An...

  16. Study on the EPR/dosimetric properties of some substituted alanines

    International Nuclear Information System (INIS)

    Polycrystalline phenyl-alanine and perdeuterated l-α-alanine (l-α-alanine-d4) were studied as potential high-energy radiation-sensitive materials (RSM) for solid state/EPR dosimetry. It was found that phenyl-alanine exhibits a linear dose response in the dose region 0.1-17kGy. However, phenyl-alanine is about 10 times less sensitive to γ-irradiation than standard l-α-alanine irradiated at the same doses. Moreover, the EPR response from phenyl-alanine is unstable and, independent of the absorbed dose, decreases by about 50% within 20 days after irradiation upon storage at room temperature. γ-irradiated polycrystalline perdeuterated l-α-alanine (CD3CD(NH2)COOH) has not previously been studied at room temperature by EPR spectroscopy. The first part of the present analysis was with respect to the structure of the EPR spectrum. By spectrum simulations, the presence of at least two radiation induced free radicals, R1=CH3C*(H)COOH and R2=H3N+-C*(CH3)COO-, was confirmed very clearly. Both these radicals were suggested previously from EPR and ENDOR studies of standard alanine crystals. The further investigations into the potential use of alanine-d4 as RSM, after choosing optimal EPR spectrometer settings parameters for this purpose, show that it is ca. two times more sensitive than standard l-α-alanine

  17. Aspartate aminotransferase catalyzed oxygen exchange with solvent from oxygen-18-enriched alpha-ketoglutarate: Evidence for slow exchange of enzyme-bound water

    Energy Technology Data Exchange (ETDEWEB)

    McLeish, M.J.; Julin, D.A.; Kirsch, J.F. (Univ. of California, Berkeley (USA))

    1989-05-02

    Partitioning of the ketimine (or ketimine + quinonoid) intermediate(s) in the mitochondrial aspartate aminotransferase reactions was investigated by following the rates of loss of {sup 18}O from carbonyl-{sup 18}O-enriched alpha-ketoglutarate together with the rate of L-glutamate formation. The ratio of these rate constants was found to equal 1 at 10{degree}C, implying that the above intermediate(s) face(s) equal barriers with respect to the forward and reverse reactions. This partition ratio of 1 together with that measured from the alpha-amino acid side of the reaction suggests that the rate constant for exchange of alpha-ketoglutarate-derived H{sub 2}(18)O from the ketimine (or ketimine + quinonoid) form(s) of the enzyme with solvent is comparable with that for kcat.

  18. Alanine/ Bromophenol Blue Polymeric Films For Radiation Dosimetry Applications

    International Nuclear Information System (INIS)

    The Polymeric dyed flexible films are considered to be the most commonly used dosimeters for routine dose monitoring in ionizing-radiation processing. Dyed polymer films prepared by simple technique of casting aqueous solution of poly (vinyl alcohol) containing bromophenol blue on horizontal glass plate are useful for high dose dosimetry. Different concentrations of L-alanine were added in presence of bromophenol blue mixed inside PVA films producing a blue film. The color has a variable absorbance with applied dose in the range from 1-35 kGy. Spectrophotometric evaluation at 602 nm for the absorbance intensity of this color was investigated as a function of dose. The used work method is uncomplicated and very easy for routine application. The radiation chemical yield G (value) was calculated in the presence and absence of alanine. Humidity during irradiation was also studied. These films show a good stability before and after irradiation under different storage conditions

  19. Alanine Radiation Detectors in Therapeutic Carbon Ion Beams

    DEFF Research Database (Denmark)

    Herrmann, Rochus; Jäkel, Oliver; Palmans, Hugo;

    proportional to absorbed dose. A model by Hansen and Olsen, based on the Track Structure Theory is available, which can predict the relative efficiency of some detectors, when the particle spectrum is known. For alanine detectors the model was successfully validated by Hansen and Olsen for several ion species...... at energies below 20 MeV/u. We implemented this model in the Monte Carlo code FLUKA. At the GSI heavy ion facility in Darmstadt, Germany, alanine has been irradiated with carbon ions at energies between 88 an 400 MeV/u, which is the energy range used for therapy. The irradiation and the detector response have...... been simulated with FLUKA. We found an agreement between measured values of the relative efficiency with values predicted by the Hansen and Olsen model with divergence less than 4%. With the implementation in FLUKA we are able to simulate the detector response in the depth dose curves with precisions...

  20. Exercise training and beta-alanine-induced muscle carnosine loading.

    OpenAIRE

    Tine eBex; Weiliang eChung; Audrey eBaguet; Eric eAchten; Wim eDerave

    2015-01-01

    Purpose. Beta-alanine (BA) supplementation has been shown to augment muscle carnosine concentration, thereby promoting high-intensity exercise performance. Trained muscles of athletes have a higher increase in carnosine concentration after BA supplementation compared to untrained muscles, but it remains to be determined whether this is due to an accumulation of acute exercise effects or to chronic adaptations from prior training. The aim of the present study was to investigate whether high-vo...

  1. Exercise Training and Beta-Alanine-Induced Muscle Carnosine Loading

    OpenAIRE

    Bex, Tine; Chung, Weiliang; Baguet, Audrey; Achten, Eric; Derave, Wim

    2015-01-01

    Purpose Beta-alanine (BA) supplementation has been shown to augment muscle carnosine concentration, thereby promoting high-intensity (HI) exercise performance. Trained muscles of athletes have a higher increase in carnosine concentration after BA supplementation compared to untrained muscles, but it remains to be determined whether this is due to an accumulation of acute exercise effects or to chronic adaptations from prior training. The aim of the present study was to investigate whether ...

  2. A thermodynamic study of La(III)L-alanine complexes

    International Nuclear Information System (INIS)

    The protonation constants of L-alanine and the complex formation constants of its La(III) complexes were determined by potentiometric studies at ionic strengths 0.06, 0.1, and 0.15 mol dm-3 (NaClO4) and at different temperatures 20, 27, and 35OC. The data together with the derived thermodynamic parameters ΔHO, ΔSO, and ΔGO are reported and discussed. (author)

  3. Physiological hypercortisolemia increases proteolysis, glutamine, and alanine production

    Energy Technology Data Exchange (ETDEWEB)

    Darmaun, D.; Matthews, D.E.; Bier, D.M. (Washington Univ. School of Medicine, St. Louis, MO (USA) Cornell Univ. Medical College, New York, NY (USA))

    1988-09-01

    Physiological elevations of plasma cortisol levels, as are encountered in stress and severe trauma, were produced in six normal subjects by infusing them with hydrocortisone for 64 h. Amino acid kinetics were measured in the postabsorptive state using three 4-h infusions of L-(1-{sup 13}C)leucine, L-phenyl({sup 2}H{sub 5})phenylalanine, L-(2-{sup 15}N)glutamine, and L-(1-{sup 13}C)alanine tracers (1) before, (2) at 12 h, and (3) at 60 h of cortisol infusion. Before and throughout the study, the subjects ate a normal diet of adequate protein and energy intake. The cortisol infusion raised plasma cortisol levels significantly from 10 {plus minus} 1 to 32 {plus minus} 4 {mu}g/dl, leucine flux from 83 {plus minus} 3 to 97 {plus minus} 3 {mu}mol{center dot}kg{sup {minus}1}{center dot}h{sup {minus}1}, and phenylalanine flux from 34 {plus minus} 1 to 39 {plus minus} 1 (SE) {mu}mol{center dot}kg{sup {minus}1}{center dot}h{sup {minus}1} after 12 h of cortisol infusion. These increases were maintained until the cortisol infusion was terminated. These nearly identical 15% increases in two different essential amino acid appearance rates are reflective of increased whole body protein breakdown. Glutamine flux rose by 12 h of cortisol infusion and remained elevated at the same level at 64 h. The increase in flux was primarily due to a 55% increase in glutamine de novo synthesis. Alanine flux increased with acute hypercortisolemia and increased further at 60 h of cortisol infusion, a result primarily of increased alanine de novo synthesis. Insulin, alanine, and lactate plasma levels responded similarly with significant rises between the acute and chronic periods of cortisol infusion. Thus hypercortisolemia increases both protein breakdown and the turnover of important nonessential amino acids for periods of up to 64 h.

  4. The Response of Alanine Dosimeters in Thermal Neutron Fields

    OpenAIRE

    Schmitz, T; Bassler, Niels; Sharpe, P; Palmans, H.; KRATZ J.v.; Langgruth, P.; HAMPEL G.

    2012-01-01

    Purpose:Boron Neutron Capture Therapy (BNCT) is a special kind of particle therapy, based on the neutron induced fission of the boron isotope 10B [1]. We have performed dosimetry experiments on the mixed neutron and gamma fields at the TRIGA Mark II research reactor in Mainz. Commonly, dosimetry in such fields is realized by foil activation and ion chambers [2]. Here we investigate alanine as an easier and more robust alternative dosimeter.Methods:We have performed four phantom experiments at...

  5. Ab initio study of alanine polypeptide chain twisting

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Yakubovich, Alexander V.; Solov'yov, Andrey V.;

    2006-01-01

    We have investigated the potential energy surfaces for alanine chains consisting of three and six amino acids. For these molecules we have calculated potential energy surfaces as a function of the Ramachandran angles ph$ and psi, which are widely used for the characterization of the polypeptide...... investigated the influence of the secondary structure of polypeptide chains on the formation of the potential energy landscape. This analysis has been performed for the sheet and the helix conformations of chains of six amino acids....

  6. Precision and sensitivity of the measurement of 15N enrichment in D-alanine from bacterial cell walls using positive/negative ion mass spectrometry

    Science.gov (United States)

    Tunlid, A.; Odham, G.; Findlay, R. H.; White, D. C.

    1985-01-01

    Sensitive detection of cellular components from specific groups of microbes can be utilized as 'signatures' in the examination of microbial consortia from soils, sediments or biofilms. Utilizing capillary gas chromatography/mass spectrometry and stereospecific derivatizing agents, D-alanine, a component localized in the prokaryotic (bacterial) cell wall, can be detected reproducibly. Enrichments of D-[15N]alanine determined in E. coli grown with [15N]ammonia can be determined with precision at 1.0 atom%. Chemical ionization with methane gas and the detection of negative ions (M - HF)- and (M - F or M + H - HF)- formed from the heptafluorobutyryl D-2 butanol ester of D-alanine allowed as little as 8 pg (90 fmol) to be detected reproducibly. This method can be utilized to define the metabolic activity in terms of 15N incorporation at the level of 10(3)-10(4) cells, as a function of the 15N-14N ratio.

  7. Uracil and beta-alanine degradation in Saccharomyces Kluyveri - discovery of a novel catabolic pathway

    DEFF Research Database (Denmark)

    Andersen, Gorm

    2006-01-01

    uracil nedbrudt via UMP og urea var et intermediat. Et nyt gen, kaldet PYD4, som er involveret i nedbrydningen af DHU, blev isoleret. PYD4 koder for en pyridoxal-5’-fosfat-afhængig aminotransferase, som har sammenlignelig aktivitet og substratspecificitet som BAL/gamma-aminobutyrate aminotransferase (BAL...

  8. ESR/alanine dosimetry applied to radiation processing

    International Nuclear Information System (INIS)

    The radiation processing of food products is specified in terms of absorbed dose, and processing quality is assessed on the basis of absorbed dose measurements. The validity of process quality control is highly dependent on the quality of the measurements and associated instrumentation; in this respect, dosimetry calibration by an Organization with official status provides an essential guarantee of validity to the quality control steps taken. The Laboratoire de Metrologie des Rayonnements Ionisants (L.M.R.I.) is the primary standards and evaluation laboratory approved by the Bureau National de Metrologie (B.N.M.), which is the French National Bureau of Standards. The LMRI implements correlation procedures in response to the various requirements which arise in connection with high doses and doserates. Such procedures are mainly based on ESR/alanine spectrometry, a dosimetry technique ideally suited to that purpose. Dosemeter geometry and design are tailored to operating conditions. Photon dosemeters consist of a detector material in powder or compacted form, and a wall with thickness and chemical composition consistent with the application. Electron dosemeters have a detector core of compacted alanine with thickness down to a few tenths of a millimeter. The ESR/alanine dosimetry technique, developed at LMRI is a flexible, reliable and accurate tool which effectively meets the various requirements arising in the field of reference dosimetry, where high doses and doserates are involved. (author)

  9. Pancreatic stellate cells support tumour metabolism through autophagic alanine secretion.

    Science.gov (United States)

    Sousa, Cristovão M; Biancur, Douglas E; Wang, Xiaoxu; Halbrook, Christopher J; Sherman, Mara H; Zhang, Li; Kremer, Daniel; Hwang, Rosa F; Witkiewicz, Agnes K; Ying, Haoqiang; Asara, John M; Evans, Ronald M; Cantley, Lewis C; Lyssiotis, Costas A; Kimmelman, Alec C

    2016-08-25

    Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease characterized by an intense fibrotic stromal response and deregulated metabolism. The role of the stroma in PDAC biology is complex and it has been shown to play critical roles that differ depending on the biological context. The stromal reaction also impairs the vasculature, leading to a highly hypoxic, nutrient-poor environment. As such, these tumours must alter how they capture and use nutrients to support their metabolic needs. Here we show that stroma-associated pancreatic stellate cells (PSCs) are critical for PDAC metabolism through the secretion of non-essential amino acids (NEAA). Specifically, we uncover a previously undescribed role for alanine, which outcompetes glucose and glutamine-derived carbon in PDAC to fuel the tricarboxylic acid (TCA) cycle, and thus NEAA and lipid biosynthesis. This shift in fuel source decreases the tumour’s dependence on glucose and serum-derived nutrients, which are limited in the pancreatic tumour microenvironment. Moreover, we demonstrate that alanine secretion by PSCs is dependent on PSC autophagy, a process that is stimulated by cancer cells. Thus, our results demonstrate a novel metabolic interaction between PSCs and cancer cells, in which PSC-derived alanine acts as an alternative carbon source. This finding highlights a previously unappreciated metabolic network within pancreatic tumours in which diverse fuel sources are used to promote growth in an austere tumour microenvironment. PMID:27509858

  10. Angular response of alanine samples: From powder to pellet

    International Nuclear Information System (INIS)

    Alanine radicals produced by irradiation can be observed through the ESR measurement of powder or in a pellet with an angular response. There are five main peaks in the ESR alanine spectrum. Usually, the central peak amplitude (A1) is chosen to perform dose measurements because it is the largest. Looking at the angular response it seems that the peak amplitude (A2) shows lower maximal deviation and standard deviations. The angular response exists from the first step of the process as powder through the granular form until the final compact pellet form. Results about the angular response on pure alanine powders and its evolution during the manufacturing process of homemade pellets, as well as commercial pellets from different suppliers are presented. The evolution of the angular response with time gives information about the stability of radicals. The manufacturing process of pellet also influences the stabilization of the radicals produced by irradiation; therefore pellet reproducibility. This study raises questions and makes proposals for a better approach to reduce measurement uncertainties for high and low doses measurements

  11. Preparation of α-alanine-3H by the interaction of atomic tritium heated up to 2000 K with a solid alanine target at 77 K

    International Nuclear Information System (INIS)

    Absorption of hydrogen by alanine targets, the target behaviour and the yield of α-alanine-3H were studied in experiments involving straight passage of H and T atoms from the sourse (2000 K) to the target (77 K) as a function of the exposure time. In the studies with 3H2 the radioactivity of the gas phase was decreasing more rapidly than the overall pressure of hydrogen: H3H accumulates more rapidly in the gas phase. Alanine decomposition products were identified. The conditions for the studies of α-alanine-3H are suggested

  12. Gamma-glutamyltransferase, aspartate aminotransferase and alkaline phosphatase as markers of alcohol consumption in out-patient alcoholics

    DEFF Research Database (Denmark)

    Gluud, C; Andersen, I; Dietrichson, O;

    1981-01-01

    Serum activity of gamma-glutamyltransferase, aspartate aminotransferase and alkaline phosphatase were determined in 316 patients attending an out-patients clinic for treatment of alcoholism. The activity of gamma-glutamyltransferase was raised in 34% and that of aspartate aminotransferase...... and alkaline phosphatase in 18% and 7%. Neither the activity of gamma-glutamyltransferase, aspartate aminotransferase nor alkaline phosphatase showed any significant (P greater than 0.05) correlation with the history of alcohol consumption. The activities of gamma-glutamyltransferase and aspartate...... aminotransferase were raised significantly more often in patients with recent alcohol consumption than in patients who had abstained for more than 9 days. The concentration of alkaline phosphatase was not significantly (P greater than 0.05) different in these groups. The predictive value of raised and normal...

  13. Purification and characterization of a branched-chain amino acid aminotransferase from Lactobacillus paracasei subsp paracasei CHCC 2115

    DEFF Research Database (Denmark)

    Thage, B.V.; Rattray, F.P.; Laustsen, M.W.;

    2004-01-01

    Purification and characterization of an aminotransferase (AT) specific for the degradation of branched-chain amino acids from Lactobacillus paracasei subsp. paracasei CHCC 2115. Methods and Results: The purification protocol consisted of anion exchange chromatography, affinity chromatography...

  14. Analysis of an Alanine/Arginine Mixture by Using TLC/FTIR Technique

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2014-01-01

    Full Text Available We applied TLC/FTIR coupled with mapping technique to analyze an alanine/arginine mixture. Narrow band TLC plates prepared by using AgI as a stationary phase were used to separate alanine and arginine. The distribution of alanine and arginine spots was manifested by a 3D chromatogram. Alanine and arginine can be successfully separated by the narrow band TLC plate. In addition, the FTIR spectra of the separated alanine and arginine spots on the narrow band TLC plate are roughly the same as the corresponding reference IR spectra.

  15. Determination of 14C-labeled plasma L + α-alanine specific radioactivity

    International Nuclear Information System (INIS)

    A method is described, which enables the specific radioactivity of 14C-labeled L + α-alanine in plasma to be determined. Plasma alanine concentration is determined spectrophotometrically using alanine dehydrogenase. In a separate procedure, this enzyme is also used to convert 14C labeled alanine and added carrier alanine, to pyruvate. The phenylhydrazone derivative of the pyruvate is then prepared and assayed for radioactivity after crystallization to constant specific radioactivity. A maximum error of 1.5 percent for any one specific radioactivity determination was found. (U.S.)

  16. The secondary structures of poly ( L-alanine) blocks in some diblock copolymers of poly( L-alanine)- b-poly(ethylene glycol) monomethyl ether in the solid state characterized by nuclear magnetic resonance and infrared spectrometry

    Science.gov (United States)

    Wu, Guo L.; Sun, Ping C.; Lin, Hai; Ma, Jian B.

    2004-02-01

    The 13C cross-polarization/magic-angle spinning (CP/MAS) spectra of the solid-state nuclear magnetic resonance (NMR) and the infrared spectra of three diblock copolymers, poly ( L-alanine)- block-poly(ethylene glycol) monomethyl ether (PLA- b-MPEG), with various proportions of two blocks were studied in comparison with those of the homopolymer poly( L-alanine), PLA, and the blends of two blocks (PLA and MPEG). The secondary structures such as α-helix and β-sheet of poly ( L-alanine) (PLA) blocks in the block copolymers could be elucidated from the signals in the solid-state 13C CP/MAS NMR spectra and transmittance peaks in the Fourier-transformation infrared (FTIR) spectra. Dramatic differences in the secondary structures were observed for the diblock copolymers, homopolymer PLA and blend samples. It was found that with the increase of the fraction of PLA block in the block copolymers, the ratio of β-sheet to α-helical conformation of PLA block went up although the α-helical conformation was much more than β-sheet conformation in total. It contradicted the general prediction of the secondary structure of homopolypeptides or PLA/PEG blends, in which the β-sheet conformation content decreased with the decrease of the polymerization degree of PLA. The investigation in FTIR spectrometry resulted in the same conclusion.

  17. Maghemite and poly-DL-alanine based core-shell multifunctional nanohybrids for environmental protection and biomedicine applications

    Science.gov (United States)

    Covaliu, Cristina Ileana; Paraschiv, Gigel; Biriş, Sorin-Ştefan; Jitaru, Ioana; Vasile, Eugeniu; Diamandescu, Lucian; Velickovic, Tanja Cirkovic; Krstic, Maja; Ionita, Valentin; Iovu, Horia; Matei, Ecaterina

    2013-11-01

    This paper deals with the synthesis of two nanohybrid materials based on maghemite (γ-Fe2O3) and poly-DL-alanine using a two-step procedure consisting of maghemite nanoparticles synthesis by microemulsion method and nanohybrids obtaining by coating of maghemite nanoparticles with poly-DL-alanine biopolymer in two different molar ratios (H1:5 and H1:15). The maghemite and their corresponding nanohybrids were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoemission spectroscopy, Mössbauer spectroscopy, Transmission electron microscopy, High resolution transmission electron microscopy with selected area electron diffraction and Atomic absorption spectroscopy. The two nanohybrids under the investigation have the average particle sizes of 22 nm and 23 nm. The Fourier transform infrared spectroscopy spectra and X-ray photoemission spectroscopy data indicate the existence of some interactions between the maghemite nanoparticles and poly-DL-alanine shell. The saturation magnetization values for maghemite and the two nanohybrids determined by a Vibrating Sample Magnetometer correspond to a typical superparamagnetic behavior suitable for applying in biomedical field. Also, with respect of biomedical application the biological activity of maghemite and its corresponding nanohybrids was investigated on healthy human cells (PBMC) and cancerous cells (HeLa). Furthermore, in order to support the multifunctionality of the γ-Fe2O3 sample and nanohybrids we also investigated their wastewater treatment properties by measuring the removal efficiency of heavy metal Cd (II) ions.

  18. Maghemite and poly-DL-alanine based core–shell multifunctional nanohybrids for environmental protection and biomedicine applications

    Energy Technology Data Exchange (ETDEWEB)

    Covaliu, Cristina Ileana, E-mail: cristina_covaliu@yahoo.com [University Politehnica of Bucharest, Faculty of Biotechnical Systems Engineering, Bucharest (Romania); Paraschiv, Gigel; Biriş, Sorin-Ştefan [University Politehnica of Bucharest, Faculty of Biotechnical Systems Engineering, Bucharest (Romania); Jitaru, Ioana; Vasile, Eugeniu [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Bucharest (Romania); Diamandescu, Lucian [National Institute of Materials Physics, Bucharest (Romania); Velickovic, Tanja Cirkovic; Krstic, Maja [University of Belgrade, Faculty of Chemistry, Belgrade (Serbia); Ionita, Valentin [University Politehnica of Bucharest, Faculty of Electrical Engineering, Bucharest (Romania); Iovu, Horia [University Politehnica of Bucharest, Faculty of Applied Chemistry and Materials Science, Bucharest (Romania); Matei, Ecaterina [University Politehnica of Bucharest, Faculty of Materials Science and Engineering, Bucharest (Romania)

    2013-11-15

    This paper deals with the synthesis of two nanohybrid materials based on maghemite (γ-Fe{sub 2}O{sub 3}) and poly-DL-alanine using a two-step procedure consisting of maghemite nanoparticles synthesis by microemulsion method and nanohybrids obtaining by coating of maghemite nanoparticles with poly-DL-alanine biopolymer in two different molar ratios (H1:5 and H1:15). The maghemite and their corresponding nanohybrids were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoemission spectroscopy, Mössbauer spectroscopy, Transmission electron microscopy, High resolution transmission electron microscopy with selected area electron diffraction and Atomic absorption spectroscopy. The two nanohybrids under the investigation have the average particle sizes of 22 nm and 23 nm. The Fourier transform infrared spectroscopy spectra and X-ray photoemission spectroscopy data indicate the existence of some interactions between the maghemite nanoparticles and poly-DL-alanine shell. The saturation magnetization values for maghemite and the two nanohybrids determined by a Vibrating Sample Magnetometer correspond to a typical superparamagnetic behavior suitable for applying in biomedical field. Also, with respect of biomedical application the biological activity of maghemite and its corresponding nanohybrids was investigated on healthy human cells (PBMC) and cancerous cells (HeLa). Furthermore, in order to support the multifunctionality of the γ-Fe{sub 2}O{sub 3} sample and nanohybrids we also investigated their wastewater treatment properties by measuring the removal efficiency of heavy metal Cd (II) ions.

  19. Selected Cytokines Serve as Potential Biomarkers for Predicting Liver Inflammation and Fibrosis in Chronic Hepatitis B Patients With Normal to Mildly Elevated Aminotransferases.

    Science.gov (United States)

    Deng, Yong-Qiong; Zhao, Hong; Ma, An-Lin; Zhou, Ji-Yuan; Xie, Shi-Bin; Zhang, Xu-Qing; Zhang, Da-Zhi; Xie, Qing; Zhang, Guo; Shang, Jia; Cheng, Jun; Zhao, Wei-Feng; Zou, Zhi-Qiang; Zhang, Ming-Xiang; Wang, Gui-Qiang

    2015-11-01

    Previous studies of small cohorts have implicated several circulating cytokines with progression of chronic hepatitis B (CHB). However, to date there have been no reliable biomarkers for assessing histological liver damage in CHB patients with normal or mildly elevated alanine aminotransferase (ALT). The aim of the present study was to investigate the association between circulating cytokines and histological liver damage in a large cohort. Also, this study was designed to assess the utility of circulating cytokines in diagnosing liver inflammation and fibrosis in CHB patients with ALT less than 2 times the upper limit of normal range (ULN). A total of 227 CHB patients were prospectively enrolled. All patients underwent liver biopsy and staging by Ishak system. Patients with at least moderate inflammation showed significantly higher levels of CXCL-11, CXCL-10, and interleukin (IL)-2 receptor (R) than patients with less than moderate inflammation (P CXCL-11 (P = 0.032) than the group without significant fibrosis. In addition, 31.8% and 29.1% of 151 patients with ALT CXCL-11 was independently associated with at least moderate inflammation, and TGF-α and IL-2R independently correlated with significant fibrosis in patients with ALT CXCL-11 was independently associated with at least moderate inflammation, whereas IL-2R and TGF-α were independent indicators of significant fibrosis in both, total CHB patients and patients with normal or mildly elevated ALT. An IL-2R and TGF-α based score (fib-index) was superior to APRI and FIB-4 for the diagnosis of significant fibrosis in patients with normal or mildly elevated ALT. PMID:26559292

  20. The mechanisms of radical formation in L-α-alanine

    International Nuclear Information System (INIS)

    Modeling of radical transformations in L-α-alanine after irradiation was performed for isolated radicals and for clusters. Special attention was devoted to the explanation of the experimental results concerning selective proton transfer and behavior of cation-radicals because a unique interpretation of the corresponding experiments is very difficult. Both semi-empirical and ab initio methods were used depending on the size of system under investigation. The results obtained show the usefulness of the computer simulation for processes in rather complex materials used in dosimetry

  1. Multifrequency electron paramagnetic resonance of irradiated L-alanine

    International Nuclear Information System (INIS)

    The radical generated by γ-irradiation of crystalline L-alanine was examined by continuous wave (CW) and pulsed electron paramagnetic resonance (EPR) at 1.8, 3.2, 4.9, 9.1 and 19.4 GHz. The spin-flip satellite lines that make a prominent contribution to the saturated spectra at 9.1 GHz are less conspicuous at lower frequencies because of overlap with the allowed transitions. The spin-lattice relaxation times measured by long-pulse saturation recovery and phase memory times measured by electron spin echo increase with increasing microwave frequency. (Author)

  2. The mechanisms of radical formation in L-{alpha}-alanine

    Energy Technology Data Exchange (ETDEWEB)

    Bugay, A.A.; Onischuk, V.A.; Petrenko, T.L.; Teslenko, V.V

    2000-05-15

    Modeling of radical transformations in L-{alpha}-alanine after irradiation was performed for isolated radicals and for clusters. Special attention was devoted to the explanation of the experimental results concerning selective proton transfer and behavior of cation-radicals because a unique interpretation of the corresponding experiments is very difficult. Both semi-empirical and ab initio methods were used depending on the size of system under investigation. The results obtained show the usefulness of the computer simulation for processes in rather complex materials used in dosimetry.

  3. Thermal stability, pH dependence and inhibition of four murine kynurenine aminotransferases

    Directory of Open Access Journals (Sweden)

    Tagle Danilo A

    2010-05-01

    Full Text Available Abstract Background Kynurenine aminotransferase (KAT catalyzes the transamination of kynunrenine to kynurenic acid (KYNA. KYNA is a neuroactive compound and functions as an antagonist of alpha7-nicotinic acetylcholine receptors and is the only known endogenous antagonist of N-methyl-D-aspartate receptors. Four KAT enzymes, KAT I/glutamine transaminase K/cysteine conjugate beta-lyase 1, KAT II/aminoadipate aminotransferase, KAT III/cysteine conjugate beta-lyase 2, and KAT IV/glutamic-oxaloacetic transaminase 2/mitochondrial aspartate aminotransferase, have been reported in mammalian brains. Because of the substrate overlap of the four KAT enzymes, it is difficult to assay the specific activity of each KAT in animal brains. Results This study concerns the functional expression and comparative characterization of KAT I, II, III, and IV from mice. At the applied test conditions, equimolar tryptophan with kynurenine significantly inhibited only mouse KAT I and IV, equimolar methionine inhibited only mouse KAT III and equimolar aspartate inhibited only mouse KAT IV. The activity of mouse KAT II was not significantly inhibited by any proteinogenic amino acids at equimolar concentrations. pH optima, temperature preferences of four KATs were also tested in this study. Midpoint temperatures of the protein melting, half life values at 65°C, and pKa values of mouse KAT I, II, III, and IV were 69.8, 65.9, 64.8 and 66.5°C; 69.7, 27.4, 3.9 and 6.5 min; pH 7.6, 5.7, 8.7 and 6.9, respectively. Conclusion The characteristics reported here could be used to develop specific assay methods for each of the four murine KATs. These specific assays could be used to identify which KAT is affected in mouse models for research and to develop small molecule drugs for prevention and treatment of KAT-involved human diseases.

  4. Synthesis and Evaluation of Novel Aromatic Substrates and Competitive Inhibitors of GABA Aminotransferase

    OpenAIRE

    Clift, Michael D.; Silverman, Richard B.

    2007-01-01

    The design, synthesis, and evaluation of novel γ-aminobutyric acid aminotransferase (GABA-AT) inhibitors and inactivators can lead to the discovery of new GABA-related therapeutics. To this end, a series of aromatic amino acid compounds was synthesized to aid in the design of new inhibitors and inactivators of GABA-AT. All compounds were tested as competitive inhibitors of GABA-AT. The amino acids with benzylic amines were also tested as substrates for GABA-AT. It was found that these compoun...

  5. Biochemical and Structural Insights into the Aminotransferase CrmG in Caerulomycin Biosynthesis.

    Science.gov (United States)

    Zhu, Yiguang; Xu, Jinxin; Mei, Xiangui; Feng, Zhan; Zhang, Liping; Zhang, Qingbo; Zhang, Guangtao; Zhu, Weiming; Liu, Jinsong; Zhang, Changsheng

    2016-04-15

    Caerulomycin A (CRM A 1) belongs to a family of natural products containing a 2,2'-bipyridyl ring core structure and is currently under development as a potent novel immunosuppressive agent. Herein, we report the functional characterization, kinetic analysis, substrate specificity, and structure insights of an aminotransferase CrmG in 1 biosynthesis. The aminotransferase CrmG was confirmed to catalyze a key transamination reaction to convert an aldehyde group to an amino group in the 1 biosynthetic pathway, preferring l-glutamate and l-glutamine as the amino donor substrates. The crystal structures of CrmG in complex with the cofactor 5'-pyridoxal phosphate (PLP) or 5'-pyridoxamine phosphate (PMP) or the acceptor substrate were determined to adopt a canonical fold-type I of PLP-dependent enzymes with a unique small additional domain. The structure guided site-directed mutagenesis identified key amino acid residues for substrate binding and catalytic activities, thus providing insights into the transamination mechanism of CrmG. PMID:26714051

  6. Structural Insight into the Mechanism of Substrate Specificity of Aedes Kynurenine Aminotransferase

    Energy Technology Data Exchange (ETDEWEB)

    Han,Q.; Gao, Y.; Robinson, H.; Li, J.

    2008-01-01

    Aedes aegypti kynurenine aminotransferase (AeKAT) is a multifunctional aminotransferase. It catalyzes the transamination of a number of amino acids and uses many biologically relevant a-keto acids as amino group acceptors. AeKAT also is a cysteine S-conjugate {beta}-lyase. The most important function of AeKAT is the biosynthesis of kynurenic acid, a natural antagonist of NMDA and {alpha}7-nicotinic acetylcholine receptors. Here, we report the crystal structures of AeKAT in complex with its best amino acid substrates, glutamine and cysteine. Glutamine is found in both subunits of the biological dimer, and cysteine is found in one of the two subunits. Both substrates form external aldemines with pyridoxal 5-phosphate in the structures. This is the first instance in which one pyridoxal 5-phosphate enzyme has been crystallized with cysteine or glutamine forming external aldimine complexes, cysteinyl aldimine and glutaminyl aldimine. All the units with substrate are in the closed conformation form, and the unit without substrate is in the open form, which suggests that the binding of substrate induces the conformation change of AeKAT. By comparing the active site residues of the AeKAT-cysteine structure with those of the human KAT I-phenylalanine structure, we determined that Tyr286 in AeKAT is changed to Phe278 in human KAT I, which may explain why AeKAT transaminates hydrophilic amino acids more efficiently than human KAT I does.

  7. Longitudinal Changes in Liver Aminotransferases Predict Metabolic Syndrome in Chinese Patients with Nonviral Hepatitis

    Institute of Scientific and Technical Information of China (English)

    CHEN Qi Cai; XIAO Juan; ZHANG Peng Peng; CHEN Li Li; CHEN Xiao Xiao; WANG Shu Mei

    2016-01-01

    ObjectiveThis study exploredthe correlation of longitudinal changes in serumalanine aminotransferase (ALT) and aspartate aminotransferase (AST)levels with the incidence of metabolic syndrome (Mets)based on a dynamic health examination cohort. MethodsA Mets-free dynamic cohortinvolving 4541 participants who underwent at leastthree health examinations from 2006 to 2011 was included in the study. Mets was defined according to the Chinese Medical Association Diabetes Branch definitionthat included hypertension, obesity, hyperlipidemia, and hyperglycemia. Generalized estimating equation (GEE) model was used to analyze multivariate relative risk (RR) of repeated observations ofALT and AST in quartiles for Mets or its components according to gender. ResultsIn all, 826Mets cases were reported. Adjustmentof relevant parameters indicated that time-varyingchanges in ALT and ASTlevels were positively associated with the incidenceof Mets in a dose-response manner. Positive association between high ALT levels and fatty liver was much stronger than that between high AST levels and fatty liver, particularly in maleparticipants. These associations were consistently observed in the following subgroups: participants with ALT and ASTlevels of ConclusionThese results suggested that elevated serum ALT and AST levels wereearly biomarkers of Mets or its components.

  8. Point mutations in the tyrosine aminotransferase gene in tyrosinemia type II.

    Science.gov (United States)

    Natt, E; Kida, K; Odievre, M; Di Rocco, M; Scherer, G

    1992-10-01

    Tyrosinemia type II (Richner-Hanhart syndrome, RHS) is a disease of autosomal recessive inheritance characterized by keratitis, palmoplantar hyperkeratosis, mental retardation, and elevated blood tyrosine levels. The disease results from deficiency in hepatic tyrosine aminotransferase (TAT; L-tyrosine:2-oxoglutarate aminotransferase, EC 2.6.1.5), a 454-amino acid protein encoded by a gene with 12 exons. To identify the causative mutations in five TAT alleles cloned from three RHS patients, chimeric genes constructed from normal and mutant TAT alleles were tested in directing TAT activity in a transient expression assay. DNA sequence analysis of the regions identified as nonfunctional revealed six different point mutations. Three RHS alleles have nonsense mutations at codons 57, 223, and 417, respectively. One "complex" RHS allele carries a GT----GG splice donor mutation in intron 8 together with a Gly----Val substitution at amino acid 362. A new splice acceptor site in intron 2 of the fifth RHS allele leads to a shift in reading frame.

  9. Sensitive non-radioactive determination of aminotransferase stereospecificity for C-4' hydrogen transfer on the coenzyme

    Energy Technology Data Exchange (ETDEWEB)

    Jomrit, Juntratip [Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400 (Thailand); Center of Excellence for Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok (Thailand); Summpunn, Pijug [Department of Biotechnology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400 (Thailand); Meevootisom, Vithaya [Department of Microbiology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400 (Thailand); Center of Excellence for Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok (Thailand); Wiyakrutta, Suthep, E-mail: scsvy@mahidol.ac.th [Department of Microbiology, Faculty of Science, Mahidol University, Rama 6 Road, Bangkok 10400 (Thailand); Center of Excellence for Agricultural Biotechnology: (AG-BIO/PERDO-CHE), Bangkok (Thailand)

    2011-02-25

    Research highlights: {yields} Stereochemical mechanism of PLP enzymes is important but difficult to determine. {yields} This new method is significantly less complicated than the previous ones. {yields} This assay is as sensitive as the radioactive based method. {yields} LC-MS/MS positively identify the analyte coenzyme. {yields} The method can be used with enzyme whose apo form is unstable. -- Abstract: A sensitive non-radioactive method for determination of the stereospecificity of the C-4' hydrogen transfer on the coenzymes (pyridoxal phosphate, PLP; and pyridoxamine phosphate, PMP) of aminotransferases has been developed. Aminotransferase of unknown stereospecificity in its PLP form was incubated in {sup 2}H{sub 2}O with a substrate amino acid resulted in PMP labeled with deuterium at C-4' in the pro-S or pro-R configuration according to the stereospecificity of the aminotransferase tested. The [4'-{sup 2}H]PMP was isolated from the enzyme protein and divided into two portions. The first portion was incubated in aqueous buffer with apo-aspartate aminotransferase (a reference si-face specific enzyme), and the other was incubated with apo-branched-chain amino acid aminotransferase (a reference re-face specific enzyme) in the presence of a substrate 2-oxo acid. The {sup 2}H at C-4' is retained with the PLP if the aminotransferase in question transfers C-4' hydrogen on the opposite face of the coenzyme compared with the reference aminotransferase, but the {sup 2}H is removed if the test and reference aminotransferases catalyze hydrogen transfer on the same face. PLP formed in the final reactions was analyzed by LC-MS/MS for the presence or absence of {sup 2}H. The method was highly sensitive that for the aminotransferase with ca. 50 kDa subunit molecular weight, only 2 mg of the enzyme was sufficient for the whole test. With this method, the use of radioactive substances could be avoided without compromising the sensitivity of the assay.

  10. β-alanine supplementation improves tactical performance but not cognitive function in combat soldiers

    OpenAIRE

    Hoffman, Jay R; Landau, Geva; Stout, Jeffrey R.; Dabora, Matan; Moran, Daniel S.; Sharvit, Nurit; Hoffman, Mattan W.; Ben Moshe, Yuval; McCormack, William P.; Hirschhorn, Gil; Ostfeld, Ishay

    2014-01-01

    Background There are no known studies that have examined β-alanine supplementation in military personnel. Considering the physiological and potential neurological effects that have been reported during sustained military operations, it appears that β-alanine supplementation may have a potential benefit in maintaining physical and cognitive performance during high-intensity military activity under stressful conditions. The purpose of this study was to examine the effect of 28 days of β-alanine...

  11. Ergogenic Effects of β-Alanine and Carnosine: Proposed Future Research to Quantify Their Efficacy

    OpenAIRE

    John Caruso; Jessica Charles; Kayla Unruh; Rachel Giebel; Lexis Learmonth; William Potter

    2012-01-01

    β-alanine is an amino acid that, when combined with histidine, forms the dipeptide carnosine within skeletal muscle. Carnosine and β-alanine each have multiple purposes within the human body; this review focuses on their roles as ergogenic aids to exercise performance and suggests how to best quantify the former’s merits as a buffer. Carnosine normally makes a small contribution to a cell’s total buffer capacity; yet β-alanine supplementation raises intracellular carnosine concentrations that...

  12. Alanine-ESR in vivo dosimetry: a feasibility study and possible applications

    International Nuclear Information System (INIS)

    A new alanine-ESR dosimeter has been developed at AERIAL in order to study its potential use in radiotherapy. Alanine-ESR results are compared with ion chamber for depth-dose measurements. A good concordance has been found between provisional dosimetry and absorbed dose during high dose rate and intra operative treatments. The results of the experiments indicate that alanine-ESR dosimetry is suited to check dose optimisation routines and seems to be a promising in vivo dosimetry technique. (Author)

  13. Application of an alanine dosimetry system for industrial irradiation and radiation protection

    International Nuclear Information System (INIS)

    This paper reports the application of alanine dosimetry in radiation processing. Continuous checks of the EPR measuring conditions as well as using high-quality alanine dosimeters and consistent technique for dose determination guarantee an accuracy of about ± 3% intermediate dose levels. The alanine dosimetry system was applied for dose mapping measurements during irradiator qualification and performance qualification of different products, routine dosimetry, and special radiation protection applications within the gamma irradiator. (author)

  14. Complex time dependence of the EPR signal of irradiated L-α-alanine

    International Nuclear Information System (INIS)

    Measurements of the EPR signal amplitude of γ-irradiated L-α-alanine with use of an adjacent reference sample have revealed variations in the signal intensity within hours and days after irradiation. The character of the time dependence of the amplitude varies with dose and the amplitude changes reach 1-1.5%. This observation favors the hypothesis that irradiated alanine contains several paramagnetic centers. Usefulness of adjacent reference samples in alanine dosimetry is also demonstrated. (Author)

  15. Polarographic studies on mixed ligand complexes involving amino acids : ternary systems, Cd-α-alanine-oxalate and Cd-β-alanine-oxalate

    International Nuclear Information System (INIS)

    Ternary complexes of cadmium(II) with oxalate as primary ligand and α- and β-alanines as secondary ligands have been studied polarographically. Formation of three mixed complex species, [Cd(amino acid) (oxalate)], [Cd(amino acid) (oxalate)2] and [Cd(anino acid)2(oxalate)], is observed in each case. The reduction is reversible and diffusion-controlled. The stability constants have been evaluated usino the method of McMasters. The α-alanine complexes are found to be more stable than the corresponding β-alanine complexes. (author)

  16. Análise sérica das enzimas aspartato aminotransferase, alanina aminotransferase e gama glutamiltranspeptidase de coelhos adultos tratados com extrato bruto de própolis

    Directory of Open Access Journals (Sweden)

    J. N. Ribeiro

    2009-01-01

    Full Text Available

    Diversos trabalhos têm atribuído a própolis inúmeras propriedades farmacológicas, dentre elas podemos citar, como exemplo, efeitos antibacteriano, antiviral, antiinflamatório, regenerador do tecido cartilaginoso, inibidor da formação de radicais livres e redutor de níveis sangüíneo de glicose e triacilglicerol. Alguns efeitos colaterais são atribuídos à própolis principalmente em doses elevadas. Muitos efeitos tóxicos da própolis são atribuídos ao álcool etílico presente no extrato.Dentre alguns efeitos tóxicos citados em literatura como realmente da própolis temos a dermatite e o aumento da uréia sangüínea. O presente estudo teve como objetivo investigar se o extrato bruto de própolis ocasiona algum efeito adverso nos níveis séricos de alanina aminotransferase, aspartato aminotransferase e gama – glutamiltranspeptidase de coelhos saudáveis. O experimento teve 30 dias de duração, sendo as dosagens dos constituintes do sangue (alanina aminotransferase, aspartato aminotransferase e gama – glutamiltranspeptidase realizadas a 0, 15 e 30 dias. Os resultados indicaram que, de o extrato bruto de própolis na forma testadea, não ocasionou alteração relevante nos níveis séricos das enzimas marcadoras de metabolismo hepático. Palavras-chave: Própolis, alanina aminotransferase, aspartato aminotransferase, gama glutamiltranpeptidase, toxicologia.

  17. Use of alanine-silicone pellets for electron paramagnetic resonance gamma dosimetry

    International Nuclear Information System (INIS)

    Silicone is proposed as an alternative binding substance in the production of D-L alanine pellets used in electron paramagnetic resonance (EPR) dosimetry of gamma rays. The dosimeters are manufactured at room temperature, making the production simple. Examination by EPR silicone-alanine pellets irradiated with 60Co gamma rays in the dose range 10 to 10(6) Gy shows that the proposed silicone binder does not affect typical alanine dose-response curves. Thermal stability of the pellets below 40 degrees C is good, but their pre-dose EPR signal amplitude is slightly higher than for nonirradiated alanine

  18. Use of alanine-silicone pellets for electron paramagnetic resonance gamma dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Flores, J.; Galindo, S. (Instituto Nacional de Investigaciones Nucleares (Mexico))

    1991-03-01

    Silicone is proposed as an alternative binding substance in the production of D-L alanine pellets used in electron paramagnetic resonance (EPR) dosimetry of gamma rays. The dosimeters are manufactured at room temperature, making the production simple. Examination by EPR silicone-alanine pellets irradiated with 60Co gamma rays in the dose range 10 to 10(6) Gy shows that the proposed silicone binder does not affect typical alanine dose-response curves. Thermal stability of the pellets below 40 degrees C is good, but their pre-dose EPR signal amplitude is slightly higher than for nonirradiated alanine.

  19. Microhardness studies on nonlinear optical -alanine single crystals

    Indian Academy of Sciences (India)

    R Hanumantharao; S Kalainathan

    2013-06-01

    Vickers and Knoop microhardness tests were carried out on grown -alanine single crystals by slow evaporation technique over a load range of 10–50 g on selected broad (2 0 3) plane. Vickers (v) and Knoop (k) microhardness for the above loads were found to be in the range of 60–71 kg/mm2 and 35–47 kg/mm2, respectively. Vickers microhardness number (v) and Knoop microhardness number (k) were found to increase with increasing load. Meyer’s index number () calculated from v shows that the material belongs to the soft material category. Using Wooster’s empirical relation, the elastic stiffness constant (11) was calculated from Vickers hardness values. Young’s modulus was calculated using Knoop hardness values. Hardness anisotropy has been observed in accordance with the orientation of the crystal.

  20. A central role for bifunctional aspartate/prephenate aminotransferase in the biosynthesis of amino acids in plant plastids.

    OpenAIRE

    El-Azaz, Jorge; Cánovas, Francisco M.; de la Torre, Fernando; Ávila, Concepción

    2014-01-01

    A central role for bifunctional aspartate/prephenate aminotransferase in the biosynthesis of amino acids in plant plastids. Fernando de la Torre, Jorge El-Azaz, Concepción Ávila, Francisco M. Cánovas Departamento de Biología Molecular y Bioquímica. Universidad de Málaga. Bifunctional aspartate/prephenate aminotransferases (AAT/PAT) are plastid-located enzymes encoded by a single locus in all reported plants, which develop two different enzymatic activities: aspartate aminotransferas...

  1. Efficient L-Alanine Production by a Thermo-Regulated Switch in Escherichia coli.

    Science.gov (United States)

    Zhou, Li; Deng, Can; Cui, Wen-Jing; Liu, Zhong-Mei; Zhou, Zhe-Min

    2016-01-01

    L-Alanine has important applications in food, pharmaceutical and veterinary and is used as a substrate for production of engineered thermoplastics. Microbial fermentation could reduce the production cost and promote the application of L-alanine. However, the presence of L-alanine significantly inhibit cell growth rate and cause a decrease in the ultimate L-alanine productivity. For efficient L-alanine production, a thermo-regulated genetic switch was designed to dynamically control the expression of L-alanine dehydrogenase (alaD) from Geobacillus stearothermophilus on the Escherichia coli B0016-060BC chromosome. The optimal cultivation conditions for the genetically switched alanine production using B0016-060BC were the following: an aerobic growth phase at 33 °C with a 1-h thermo-induction at 42 °C followed by an oxygen-limited phase at 42 °C. In a bioreactor experiment using the scaled-up conditions optimized in a shake flask, B0016-060BC accumulated 50.3 g biomass/100 g glucose during the aerobic growth phase and 96 g alanine/100 g glucose during the oxygen-limited phase, respectively. The L-alanine titer reached 120.8 g/l with higher overall and oxygen-limited volumetric productivities of 3.09 and 4.18 g/l h, respectively, using glucose as the sole carbon source. Efficient cell growth and L-alanine production were reached separately, by switching cultivation temperature. The results revealed the application of a thermo-regulated strategy for heterologous metabolic production and pointed to strategies for improving L-alanine production.

  2. Activation of tyrosine aminotransferase expression in fetal liver by 5-azacytidine

    Energy Technology Data Exchange (ETDEWEB)

    Rothrock, R.; Perry, S.T.; Isham, K.R.; Lee, K.L.; Kenney, F.T.

    1983-06-15

    Rat fetuses of 20 days gestational age were treated in utero with the inhibitor of DNA methylation, 5-azacytidine. The liver enzyme tyrosine aminotransferase, normally expressed at very low levels until several hours after birth, was increased by the drug in the fetal livers after a lag period of about 9 hours, reaching a level 70-fold above control levels 18 hours after treatment. The high levels attained after 5-azacytidine treatment are comparable to those of glucocorticoid-treated adult livers, and were not further increased by administration of hydrocortisone to dams carrying treated fetuses. Cytidine and two other analogs, cytosine arabinoside and 6-azacytidine, were essentially without effect. 15 references, 2 figures, 1 table.

  3. Endurance exercise increases skeletal muscle kynurenine aminotransferases and plasma kynurenic acid in humans.

    Science.gov (United States)

    Schlittler, Maja; Goiny, Michel; Agudelo, Leandro Z; Venckunas, Tomas; Brazaitis, Marius; Skurvydas, Albertas; Kamandulis, Sigitas; Ruas, Jorge L; Erhardt, Sophie; Westerblad, Håkan; Andersson, Daniel C

    2016-05-15

    Physical exercise has emerged as an alternative treatment for patients with depressive disorder. Recent animal studies show that exercise protects from depression by increased skeletal muscle kynurenine aminotransferase (KAT) expression which shifts the kynurenine metabolism away from the neurotoxic kynurenine (KYN) to the production of kynurenic acid (KYNA). In the present study, we investigated the effect of exercise on kynurenine metabolism in humans. KAT gene and protein expression was increased in the muscles of endurance-trained subjects compared with untrained subjects. Endurance exercise caused an increase in plasma KYNA within the first hour after exercise. In contrast, a bout of high-intensity eccentric exercise did not lead to increased plasma KYNA concentration. Our results show that regular endurance exercise causes adaptations in kynurenine metabolism which can have implications for exercise recommendations for patients with depressive disorder. PMID:27030575

  4. An alternative pathway contributes to phenylalanine biosynthesis in plants via a cytosolic tyrosine:phenylpyruvate aminotransferase.

    Science.gov (United States)

    Yoo, Heejin; Widhalm, Joshua R; Qian, Yichun; Maeda, Hiroshi; Cooper, Bruce R; Jannasch, Amber S; Gonda, Itay; Lewinsohn, Efraim; Rhodes, David; Dudareva, Natalia

    2013-01-01

    Phenylalanine is a vital component of proteins in all living organisms, and in plants is a precursor for thousands of additional metabolites. Animals are incapable of synthesizing phenylalanine and must primarily obtain it directly or indirectly from plants. Although plants can synthesize phenylalanine in plastids through arogenate, the contribution of an alternative pathway via phenylpyruvate, as occurs in most microbes, has not been demonstrated. Here we show that plants also utilize a microbial-like phenylpyruvate pathway to produce phenylalanine, and flux through this route is increased when the entry point to the arogenate pathway is limiting. Unexpectedly, we find the plant phenylpyruvate pathway utilizes a cytosolic aminotransferase that links the coordinated catabolism of tyrosine to serve as the amino donor, thus interconnecting the extra-plastidial metabolism of these amino acids. This discovery uncovers another level of complexity in the plant aromatic amino acid regulatory network, unveiling new targets for metabolic engineering.

  5. Characterization of lithium formate EPR dosimeters for high dose applications – comparison with alanine

    DEFF Research Database (Denmark)

    Waldeland, Einar; Helt-Hansen, Jakob; Malinen, Eirik

    2011-01-01

    signal per ºC change in irradiation temperature) were 0.154 % K−1 and 0.161 % K−1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The saturation...

  6. Transients and stable radical from the deamination of α-alanine

    International Nuclear Information System (INIS)

    The objects of investigation were single crystals of L-α-alanine, in which radical anion CH3 C·H CO2- has been formed by radiation induced deamination of alanine. Previously, this stable radical has been spectrally identified (λmax=350 nm, ε=1100 M-1 x cm-1), and its characteristics have found to be identical with characteristics of the same radical obtained by pulse radiolysis in aqueous solution. The mechanism of radical formation in the solid state is not known. Time resolved pulse radiolysis of single crystal alanine has shown more complicated way of the formation of the same radical in solid state than in aqueous solution. The electrons abstracted from the solid alanine molecule neutralise positive the charge of zwitter-ion alanine. Ammonia is leaving the reaction-complex in time of milliseconds, leaving the stable radical anion. (author)

  7. Uses of polymer-alanine film/ESR dosimeters in dosimetry of ionizing radiation

    International Nuclear Information System (INIS)

    Alanine ESR dosimetry is a reliable method, used in a various fields of ionizing radiation. The polymer-alanine film/ESR dosimeters of 0.3 -0.4 mm thickness were prepared and their dosimetric properties were studied for 60Co γ photons and 3 - 5 MeV electrons in the dose range from 20 Gy to 100 kGy. The results show that under normal conditions the alanine calibration curves are linear in the dose range from 100 Gy to 10kGy. The dose profiles at the electron radiation field were measured with the film alanine dosimeters. The polymer-alanine film dosimeters were used for ion implantation of 400 keV ion implantor. Their dose response and energy dependence were investigated initially. (Author)

  8. Ergogenic Effects of β-Alanine and Carnosine: Proposed Future Research to Quantify Their Efficacy

    Directory of Open Access Journals (Sweden)

    John Caruso

    2012-06-01

    Full Text Available β-alanine is an amino acid that, when combined with histidine, forms the dipeptide carnosine within skeletal muscle. Carnosine and β-alanine each have multiple purposes within the human body; this review focuses on their roles as ergogenic aids to exercise performance and suggests how to best quantify the former’s merits as a buffer. Carnosine normally makes a small contribution to a cell’s total buffer capacity; yet β-alanine supplementation raises intracellular carnosine concentrations that in turn improve a muscle’s ability to buffer protons. Numerous studies assessed the impact of oral β-alanine intake on muscle carnosine levels and exercise performance. β-alanine may best act as an ergogenic aid when metabolic acidosis is the primary factor for compromised exercise performance. Blood lactate kinetics, whereby the concentration of the metabolite is measured as it enters and leaves the vasculature over time, affords the best opportunity to assess the merits of β-alanine supplementation’s ergogenic effect. Optimal β-alanine dosages have not been determined for persons of different ages, genders and nutritional/health conditions. Doses as high as 6.4 g day−1, for ten weeks have been administered to healthy subjects. Paraesthesia is to date the only side effect from oral β-alanine ingestion. The severity and duration of paraesthesia episodes are dose-dependent. It may be unwise for persons with a history of paraesthesia to ingest β-alanine. As for any supplement, caution should be exercised with β-alanine supplementation.

  9. Crystallization and preliminary X-ray diffraction analysis of l,l-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii

    OpenAIRE

    Hudson, André O.; Girón, Irma; Dobson, Renwick C. J.

    2010-01-01

    A variant of the diaminopimelate/lysine pathway has recently been defined following the discovery of the enzyme l,l-diaminopimelate aminotransferase (DapL). The cloning of the cDNA, recombinant expression, purification and preliminary diffraction analysis of DapL from the alga C. reinhardtii are presented.

  10. The effect of portacaval anastomosis on the expression of glutamine synthetase and ornithine aminotransferase in perivenous hepatocytes.

    Science.gov (United States)

    da Silva, Robin; Levillain, Oliver; Brosnan, John T; Araneda, Silvia; Brosnan, Margaret E

    2013-05-01

    There is functional zonation of metabolism across the liver acinus, with glutamine synthetase restricted to a narrow band of cells around the terminal hepatic venules. Portacaval anastomosis, where there is a major rerouting of portal blood flow from the portal vein directly to the vena cava bypassing the liver, has been reported to result in a marked decrease in the activity of glutamine synthetase. It is not known whether this represents a loss of perivenous hepatocytes or whether there is a specific loss of glutamine synthetase. To answer this question, we have determined the activity of glutamine synthetase and another enzyme from the perivenous compartment, ornithine aminotransferase, as well as the immunochemical localization of both glutamine synthetase and ornithine aminotransferase in rats with a portacaval shunt. The portacaval shunt caused a marked decrease in glutamine synthetase activity and an increase in ornithine aminotransferase activity. Immunohistochemical analysis showed that the glutamine synthetase and ornithine aminotransferase proteins maintained their location in the perivenous cells. These results indicate that there is no generalized loss of perivenous hepatocytes, but rather, there is a significant alteration in the expression of these proteins and hence metabolism in this cell population.

  11. Nonalcoholic Steatohepatitis and Hepatic Fibrosis in HIV-1–Monoinfected Adults With Elevated Aminotransferase Levels on Antiretroviral Therapy

    Science.gov (United States)

    Morse, Caryn G.; McLaughlin, Mary; Matthews, Lindsay; Proschan, Michael; Thomas, Francine; Gharib, Ahmed M.; Abu-Asab, Mones; Orenstein, Abigail; Engle, Ronald E.; Hu, Xiaojun; Lempicki, Richard; Hadigan, Colleen; Kleiner, David E.; Heller, Theo; Kovacs, Joseph A.

    2015-01-01

    Background. Persistent aminotransferase elevations are common in human immunodeficiency virus (HIV)–infected patients on antiretroviral therapy (ART), including those without hepatitis B or C coinfection, but their clinical significance is unknown. Methods. HIV-infected adults with aminotransferase levels elevated above the upper limit of normal for ≥6 months while receiving ART, and without chronic viral hepatitis or other known causes of chronic liver disease, underwent a detailed metabolic assessment and liver biopsy. Results. Sixty-two HIV-infected subjects completed the study. Forty (65%) had clinically significant liver pathology, including 34 (55%) with nonalcoholic steatohepatitis (NASH) and 11 (18%) with bridging fibrosis, 10 of whom also had NASH. Nonspecific abnormalities alone were seen in 22 (35%) subjects, including mild steatosis, mild to moderate inflammation, and evidence of drug adaptation. Insulin resistance, obesity, and the presence of either of 2 minor alleles in the PNPLA3 gene were significantly associated with increased risk of NASH and fibrosis. NASH and/or fibrosis were not associated with duration of HIV infection or ART, specific antiretroviral drugs, history of opportunistic infection, immune status, or duration of aminotransferase elevation. Conclusions. HIV-infected adults with chronic aminotransferase elevations while receiving ART have a high rate of liver disease. Noninvasive testing can help identify liver disease in such patients, but liver biopsy is necessary to definitively identify those at risk for liver disease progression and complications. Longitudinal follow-up of this cohort will better characterize the natural history of aminotransferase elevations in this population and identify noninvasive biomarkers of liver disease progression. PMID:25681381

  12. Identification of a mutation affecting an alanine-alpha-ketoisovalerate transaminase activity in Escherichia coli K-12.

    Science.gov (United States)

    Falkinham, J O

    1979-10-01

    A mutation affecting alanine-alpha-ketoisovalerate transaminase activity has been shown to be cotransducible with ilv gene cluster. The transaminase deficiency results in conditional isoleucine auxotrophy in the presence of alanine. PMID:396446

  13. Thermochemical Study of Lanthanum Complex Crystal with β-Alanine

    Institute of Scientific and Technical Information of China (English)

    陈平初; 屈松生; 詹正坤; 吴新明

    2002-01-01

    Lanthanum complex crystal with β-alanine (1∶3) was synthesized. Through the DTA,TG,chemistry analysis and comparison with literature, it shows that its form is {[La2(β-ala)6* (H2O)4](ClO4)6*H2O}n, and its purity is 98.86%. The dissolution enthalpy of the reactants and products in 2 mol*L-1 HCl solution (298.15K) was measured by using the isoperibol reaction calorimetry. ΔrHm was calculated by a designed thermochemical cycle of the coordination reaction. From the results and other auxiliary quantities, the standard molar enthalpy of formation of [La2(β-ala)6*(H2O)4](ClO4)6*H2O is obtained to be ΔfHm°{[La2(β-ala)6*(H2O)4](ClO4)6*H2O} = - 7062.911 kJ*mol-1.

  14. Detection of low- and high-LET radiation with alanine

    International Nuclear Information System (INIS)

    Production and accumulation of free radicals in some crystalline biomolecules are relatively stable products of a sequence of events inititated by the absorption of radiation energy. Free radicals can qualitatively and quantitatively be analyzed by means of electron spin resonance, ESR, spectroscopy, and the measure of radical concentration may thus be used for dosimetry purposes. For practical application in radiation dosimetry the crystalline amino acid L-α-alanine is pressed into pellets, 4.5 mm in diameter by 2 mm in thickness, with 5% by weight polyvinyl-pyrrolidinone (C4H6N0-CH=CH2)sub(n) added as a binding material. The dose meter is robust and easy to handle, and the read-out technique is non-destructive with respect to the measured signal. The useful dose range is from 0.5 to 105 Gy with + - 0.4% reproducibility of measurement. Hence, the dose meter can be used in radiation processing of food, for sterilization, as a postal dose meter for intercalibration of radiation facilities, for control and documentation of radiation therapy doses, and as a personal accident dose meter for radiation workers. (author)

  15. Carbon-11 labelled analogs of alanine by the Strecker synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Prenant, C.; Theobald, A.; Siegel, T.; Joachim, J.; Weber, K.; Haberkorn, U.; Oberdorfer, F. [Deutsches Krebsforschungszentrum, Heidelberg (Germany)

    1995-06-01

    Derivatives of alanine, {alpha}-[2-sup(11)C]aminoisobutyric acid 1a and {alpha}-(N-methyl)-[2-{sup 11} C]aminoisobutyric acid 1b were prepared for the in-vivo study of amino acid transport phenomena by positron-emission-tomography (PET). Compounds 1a and 1b were obtained by a Zelinski-Stadnikoff variant of the Strecker {alpha}-amino acid synthesis from in-situ formed [{sup 11} C]acetone in presence of sodium cyanide and either ammonium sulfate (for 1a) or methylamine hydrochloride (for 1b). The complete preparation required 50 min from the end of [{sup 11}C]CO{sub 2} production, and delivered 1.2 - 2 GBq of labelled product for application (2.4 -4%); not corrected for decay; related to trapped [{sup C}]CO{sub 2}. The specific activity of the labelled products was 16 to 20 GBq{center_dot}{mu}mol{sup -1}. The radiochemical and chemical purity of the preparations was greater than 98%. (Author).

  16. Detection of low- and high-LET radiation with alanine

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, J.W.; Olsen, K.J.

    1986-01-01

    Production and accumulation of free radicals in some crystalline biomolecules are relatively stable products of a sequence of events inititated by the absorption of radiation energy. Free radicals can qualitatively and quantitatively be analyzed by means of electron spin resonance, ESR, spectroscopy, and the measure of radical concentration may thus be used for dosimetry purposes. For practical application in radiation dosimetry the crystalline amino acid L-..cap alpha..-alanine is pressed into pellets, 4.5 mm in diameter by 2 mm in thickness, with 5% by weight polyvinyl-pyrrolidinone (C/sub 4/H/sub 6/N0-CH=CH/sub 2/)sub(n) added as a binding material. The dose meter is robust and easy to handle, and the read-out technique is non-destructive with respect to the measured signal. The useful dose range is from 0.5 to 10/sup 5/ Gy with + - 0.4% reproducibility of measurement. Hence, the dose meter can be used in radiation processing of food, for sterilization, as a postal dose meter for intercalibration of radiation facilities, for control and documentation of radiation therapy doses, and as a personal accident dose meter for radiation workers.

  17. The metabolism of histamine in the Drosophila optic lobe involves an ommatidial pathway: β-alanine recycles through the retina

    OpenAIRE

    Borycz, Janusz; Borycz, Jolanta A.; Edwards, Tara N.; Boulianne, Gabrielle L.; Ian A Meinertzhagen

    2012-01-01

    Flies recycle the photoreceptor neurotransmitter histamine by conjugating it to β-alanine to form β-alanyl-histamine (carcinine). The conjugation is regulated by Ebony, while Tan hydrolyses carcinine, releasing histamine and β-alanine. In Drosophila, β-alanine synthesis occurs either from uracil or from the decarboxylation of aspartate but detailed roles for the enzymes responsible remain unclear. Immunohistochemically detected β-alanine is present throughout the fly’s entire brain, and is en...

  18. Calculation and Comparison of Energy Interaction and Intensity Parameters for the Interaction of Nd(III with DL-Valine, DL-Alanine and β-Alanine in Presence and Absence of Ca2+/Zn2+ in Aqueous and Different Aquated Organic Solvents Using 4f-4f Transition Spectra as Probe

    Directory of Open Access Journals (Sweden)

    H. Debecca Devi

    2009-01-01

    Full Text Available Absorption difference and comparative absorption spectrophotometric studies involving 4f-4f transitions of Nd(III and different amino acids: DL-valine, DL-alanine, and β-alanine in presence and absence of Ca(II and Zn(II in aqueous and different aquated organic solvents have been carried out. Variations in the spectral energy parameters: Slater-Condon (FK factor, Racah (EK, Lande factor (ξ4f, nephelauxetic ratio (β, bonding (b1/2, percentage covalency (δ are calculated to explore the mode of interaction of Nd(III with different amino acids: DL-valine, DL-alanine, and β-alanine. The values of experimentally calculated oscillator strength (P and computed values of Judd-Ofelt electric dipole intensity parameters, Tλ (λ = 2,4,6, are also determined for different 4f-4f transitions. The variation in the values of P and Tλ parameters explicitly shows the relative sensitivities of the 4f-4f transitions as well as the specific correlation between relative intensities, ligand structures, and nature of Nd(III-ligand interaction.

  19. β - Alanine protects mice from memory deficits induced by ageing, scopolamine, diazepam and ethanol

    Directory of Open Access Journals (Sweden)

    Dhingra D

    2006-01-01

    Full Text Available The present study was undertaken to investigate the effects of β-alanine (a glycine agonist, on learning and memory in mice. β-alanine (5, 10, 20 and 40 mg/kg i.p. was administered for 6 successive days, to young (3 months old and aged-mice (16 months old. The learning and memory parameters were assessed, using elevated plus-maze and passive-avoidance apparatus. The effect of β-alanine (20 mg/kg for 6 days on locomotor function of young and aged mice, was studied using photoactometer, to rule out the increase in locomotor performance of mice. β-alanine at both the doses (10 and 20 mg/kg, significantly improved learning and memory of young- and aged- mice. β-alanine also reversed scopolamine (0.4 mg/kg i.p., ethanol (1.0 g/kg i.p. and diazepam (1.0 mg/kg i.p. -induced amnesia in young mice. There was no significant effect of β-alanine on the locomotor activity of both young and aged mice. The probable underlying mechanism of the memory-enhancing effect of β-alanine appears to be related to its antioxidant, anti-amyloid and procholinergic activities.

  20. Importance of intrahepatic mechanisms to gluconeogenesis from alanine during exercise and recovery

    Energy Technology Data Exchange (ETDEWEB)

    Wasserman, D.H.; Williams, P.E.; Lacy, D.B.; Green, D.R.; Cherrington, A.D.

    1988-04-01

    These studies were performed to assess the importance of intrahepatic mechanisms to gluconeogenesis in the dog during 150 min of treadmill exercise and 90 min of recovery. Sampling catheters were implanted in an artery and portal and hepatic veins 16 days before experimentation. Infusions of (U-/sup 14/C)alanine, (3-/sup 3/H)glucose, and indocyanine green were used to assess gluconeogenesis. During exercise, a decline in arterial and portal vein plasma alanine and in hepatic blood flow led to a decrease in hepatic alanine delivery. During recovery, hepatic blood flow was restored to basal, causing an increase in hepatic alanine delivery beyond exercise rates but still below resting rates. Hepatic fractional alanine extraction increased from 0.26 +/- 0.02 at rest to 0.64 +/- 0.03 during exercise and remained elevated during recovery. Net hepatic alanine uptake was 2.5 +/- 0.2 mumol.kg-1.min-1 at rest and remained unchanged during exercise but was increased during recovery. The conversion rate of (/sup 14/C)alanine to glucose had increased by 248 +/- 38% by 150 min of exercise and had increased further during recovery. The efficiency with which alanine was channeled into glucose in the liver was accelerated to a rate of 338 +/- 55% above basal by 150 min of exercise but declined slightly during recovery. In conclusion, 1) gluconeogenesis from alanine is accelerated during exercise, due to an increase in the hepatic fractional extraction of the amino acid and through intrahepatic mechanisms that more efficiently channel it into glucose.

  1. Spectroscopic Evidence for an Oxazolone Structure of the b(2) Fragment Ion from Protonated Tri-Alanine

    NARCIS (Netherlands)

    Oomens, J.; Young, S.; Molesworth, S.; Van Stipdonk, M.

    2009-01-01

    Infrared multiple photon dissociation (IRMPD) spectroscopy is used to identify the structure of the b(2)(+) ion generated from protonated tri-alanine by collision induced dissociation (CID). The IRMPD spectrum of b(2)(+) differs markedly from that of protonated cyclo-alanine-alanine, demonstrating t

  2. Response of L-alanine and 2-methylalanine minidosimeters for K-Band (24 GHz) EPR dosimetry

    Science.gov (United States)

    Chen, F.; Graeff, C. F. O.; Baffa, O.

    2007-11-01

    Minidosimeters of L-alanine and 2-methylalanine (2MA) were prepared and tested as potential candidates for small radiation field dosimetry. To quantify the free radicals created by radiation a K-Band (24 GHz) EPR spectrometer was used. X-rays provided by a 6 MV clinical linear accelerator were used to irradiate the minidosimeters in the dose range of 0.5-30 Gy. The dose-response curves for both radiation sensitive materials displayed a good linear behavior in the dose range indicated with 2MA being more radiation sensitive than L-alanine. Moreover, 2MA showed a smaller LLD (lower limit detection) value. The proposed system minidosimeter/K-Band spectrometer was able to detect 10 Gy EPR spectra with good signal-to-noise ratio (S/N). The overall uncertainty indicates that this system shows a good performance for the detection of dose values of 20 Gy and above, which are dose values typically used in radiosurgery treatments.

  3. Response of L-alanine and 2-methylalanine minidosimeters for K-Band (24 GHz) EPR dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Chen, F. [Department of Physics and Mathematics, FFCLRP, University of Sao Paulo, 14040-901 Ribeirao Preto, SP (Brazil)], E-mail: epr2h@yahoo.com; Graeff, C.F.O. [Department of Physics, FC, State University of Sao Paulo, 17033-360 Bauru (Brazil); Baffa, O. [Department of Physics and Mathematics, FFCLRP, University of Sao Paulo, 14040-901 Ribeirao Preto, SP (Brazil)], E-mail: baffa@ffclrp.usp.br

    2007-11-15

    Minidosimeters of L-alanine and 2-methylalanine (2MA) were prepared and tested as potential candidates for small radiation field dosimetry. To quantify the free radicals created by radiation a K-Band (24 GHz) EPR spectrometer was used. X-rays provided by a 6 MV clinical linear accelerator were used to irradiate the minidosimeters in the dose range of 0.5-30 Gy. The dose-response curves for both radiation sensitive materials displayed a good linear behavior in the dose range indicated with 2MA being more radiation sensitive than L-alanine. Moreover, 2MA showed a smaller LLD (lower limit detection) value. The proposed system minidosimeter/K-Band spectrometer was able to detect 10 Gy EPR spectra with good signal-to-noise ratio (S/N). The overall uncertainty indicates that this system shows a good performance for the detection of dose values of 20 Gy and above, which are dose values typically used in radiosurgery treatments.

  4. Effect of the ionizing radiation on alanine solution for a dosimeter application

    International Nuclear Information System (INIS)

    The amino acid alanine is well known as a dosimetric detector material for high level dosimetry. Its application is based on the formation of radicals by ionising radiation. In this study the effect of several parameters such as: the ionising radiation, the concentration, the dose on the pH, conductivity and the oscillotitrometric answer of Lalanine solution was investigated. The results show that there is a significant production of new species. The formation of these species increases upon increasing dose. The comparison between the repeatability of the used techniques led us to choose of the system alanine/pH and the alanine/conductivity as the most adapted. (Author)

  5. Temperature dependences of piezoelectric, elastic and dielectric constants of L-alanine crystal

    Energy Technology Data Exchange (ETDEWEB)

    Tylczynski, Z; Sterczynska, A; Wiesner, M, E-mail: zbigtyl@amu.edu.pl [Faculty of Physics, Adam Mickiewicz University, Umultowska 85, 61-614 Poznan (Poland)

    2011-09-07

    Temperature changes in the components of piezoelectric, elastic and dielectric tensors were studied in L-alanine crystals in the range 100-300 K. A jumpwise increase in the c{sub 55} component of the elastic stiffness accompanied by maxima in damping of all face-shear modes observed at 199 K in L-alanine crystal were interpreted as a result of changes in the NH{sub 3}{sup +} vibrations occurring through electron-phonon coupling. All components of the piezoelectric tensor show small anomalies in this temperature range. The components of the electromechanical coupling coefficient determined indicate that L-alanine is a weak piezoelectric. (paper)

  6. Temperature dependences of piezoelectric, elastic and dielectric constants of L-alanine crystal

    International Nuclear Information System (INIS)

    Temperature changes in the components of piezoelectric, elastic and dielectric tensors were studied in L-alanine crystals in the range 100-300 K. A jumpwise increase in the c55 component of the elastic stiffness accompanied by maxima in damping of all face-shear modes observed at 199 K in L-alanine crystal were interpreted as a result of changes in the NH3+ vibrations occurring through electron-phonon coupling. All components of the piezoelectric tensor show small anomalies in this temperature range. The components of the electromechanical coupling coefficient determined indicate that L-alanine is a weak piezoelectric. (paper)

  7. Electron spin relaxation times for the alanine radical in two dosimeters

    International Nuclear Information System (INIS)

    The spin-lattice relaxation times for the alanine radical in dosimeters were measured by long-pulse saturation recovery and by inversion recovery. The strong dependence of the recovery time constants on experimental conditions show that spectral diffusion processes contribute to enhanced relaxation rates, analogous to what was observed previously for 60Co γ-irradiated polycrystalline L-alanine. The spectral diffusion processes make it possible to run quantitative CW spectra of the alanine radical at substantially higher microwave powers than could be used in the absence of spectral diffusion processes

  8. A thin alanine-polyethylene film dosimetry system with diffuse reflection spectrophotometric evaluation

    International Nuclear Information System (INIS)

    Characteristics of a new alanine dosimeter in the shape of a thin film, with the measurement of optical absorption of the CH3CHCOO- radical is described. That type of dosimeter, ALA/DRS (for diffuse reflection spectrophotometry) is compared, to an alanine dosimeter with EPR evaluation (ALA/EPR for short). In many respects the simple ALA/DRS version, as the alanine-polyethylene composite is superior. The paper shows the importance of the new experimental approach to free radical research in solid state radiation chemistry. (author). 7 refs., 3 figs

  9. Temperature stabilization of alanine dosimeters used for food processing and sterilization

    International Nuclear Information System (INIS)

    The International Atomic Energy Agency has established a dose quality audit service for radiation processing facilities. The objective of the service is to provide an independent check on the routine dosimetry system in use at the facility. The audit service is based on the use of alanine EPR dosimetry. Generally, alanine dosimeters are irradiated at the facility together with a product, and the response is then analyzed at the IAEA laboratory. Practice of the audit service has shown that the main uncertainty in alanine dosimetry is due to absence of temperature control at the irradiation facilities. Here, a method for stabilizing the temperature of the dosimeter during irradiation is proposed

  10. Bicyclic γ-amino acids as inhibitors of γ-aminobutyrate aminotransferase.

    Science.gov (United States)

    Pinto, Andrea; Tamborini, Lucia; Pennacchietti, Eugenia; Coluccia, Antonio; Silvestri, Romano; Cullia, Gregorio; De Micheli, Carlo; Conti, Paola; De Biase, Daniela

    2016-01-01

    The γ-aminobutyrate (GABA)-degradative enzyme GABA aminotransferase (GABA-AT) is regarded as an attractive target to control GABA levels in the central nervous system: this has important implications in the treatment of several neurological disorders and drug dependencies. We have investigated the ability of newly synthesized compounds to act as GABA-AT inhibitors. These compounds have a unique bicyclic structure: the carbocyclic ring bears the GABA skeleton, while the fused 3-Br-isoxazoline ring contains an electrophilic warhead susceptible of nucleophilic attack by an active site residue of the target enzyme. Out of the four compounds tested, only the one named (+)-3 was found to significantly inhibit mammalian GABA-AT in vitro. Docking studies, performed on the available structures of GABA-AT, support the experimental findings: out of the four tested compounds, only (+)-3 suitably orients the electrophilic 3-Br-isoxazoline warhead towards the active site nucleophilic residue Lys329, thereby explaining the irreversible inhibition of GABA-AT observed experimentally. PMID:25807299

  11. Strain relief at the active site of phosphoserine aminotransferase induced by radiation damage.

    Science.gov (United States)

    Dubnovitsky, Anatoly P; Ravelli, Raimond B G; Popov, Alexander N; Papageorgiou, Anastassios C

    2005-06-01

    The X-ray susceptibility of the lysine-pyridoxal-5'-phosphate Schiff base in Bacillus alcalophilus phosphoserine aminotransferase has been investigated using crystallographic data collected at 100 K to 1.3 A resolution, complemented by on-line spectroscopic studies. X-rays induce deprotonation of the internal aldimine, changes in the Schiff base conformation, displacement of the cofactor molecule, and disruption of the Schiff base linkage between pyridoxal-5'-phosphate and the Lys residue. Analysis of the "undamaged" structure reveals a significant chemical strain on the internal aldimine bond that leads to a pronounced geometrical distortion of the cofactor. However, upon crystal exposure to the X-rays, the strain and distortion are relaxed and eventually diminished when the total absorbed dose has exceeded 4.7 x 10(6) Ggamma. Our data provide new insights into the enzymatic activation of pyridoxal-5'-phosphate and suggest that special care should be taken while using macromolecular crystallography to study details in strained active sites.

  12. Jasmonate is involved in the induction of tyrosine aminotransferase and tocopherol biosynthesis in Arabidopsis thaliana.

    Science.gov (United States)

    Sandorf, Iris; Holländer-Czytko, Heike

    2002-11-01

    Coronatine-inducible tyrosine aminotransferase (TAT), which catalyses the transamination from tyrosine to p-hydroxyphenylpyruvate, is the first enzyme of a pathway leading via homogentisic acid to plastoquinone and tocopherols, the latter of which are known to be radical scavengers in plants. TAT can be also induced by the octadecanoids methyl jasmonate (MeJA) and methyl-12-oxophytodienoic acid (MeOPDA), as well as by wounding, high light, UV light and the herbicide oxyfluorfen. In order to elucidate the role of octadecanoids in the process of TAT induction in Arabidopsis thaliana (L.) Heynh., the jasmonate-deficient mutant delayed dehiscence (dde1) was used, in which the gene for 12-oxophytodienoic acid reductase 3 is disrupted. The amount of immunodetectable TAT was low. The enzyme was still fully induced by coronatine as well as by MeJA although induction by the latter was to a lesser extent and later than in the wild type. Treatment with MeOPDA, wounding and UV light, however, had hardly any effects. Tocopherol levels that showed considerable increases in the wild type after some treatments were much less affected in the mutant. However, starting levels of tocopherol were higher in non-induced dde1 than in the wild type. We conclude that jasmonate plays an important role in the signal transduction pathway regulating TAT activity and the biosynthesis of its product tocopherol. PMID:12430028

  13. Characteristic features of kynurenine aminotransferase allosterically regulated by (alpha-ketoglutarate in cooperation with kynurenine.

    Directory of Open Access Journals (Sweden)

    Ken Okada

    Full Text Available Kynurenine aminotransferase from Pyrococcus horikoshii OT3 (PhKAT, which is a homodimeric protein, catalyzes the conversion of kynurenine (KYN to kynurenic acid (KYNA. We analyzed the transaminase reaction mechanisms of this protein with pyridoxal-5'-phosphate (PLP, KYN and α-ketoglutaric acid (2OG or oxaloacetic acid (OXA. 2OG significantly inhibited KAT activities in kinetic analyses, suggesting that a KYNA biosynthesis is allosterically regulated by 2OG. Its inhibitions evidently were unlocked by KYN. 2OG and KYN functioned as an inhibitor and activator in response to changes in the concentrations of KYN and 2OG, respectively. The affinities of one subunit for PLP or 2OG were different from that of the other subunit, as confirmed by spectrophotometry and isothermal titration calorimetry, suggesting that the difference of affinities between subunits might play a role in regulations of the KAT reaction. Moreover, we identified two active and allosteric sites in the crystal structure of PhKAT-2OG complexes. The crystal structure of PhKAT in complex with four 2OGs demonstrates that two 2OGs in allosteric sites are effector molecules which inhibit the KYNA productions. Thus, the combined data lead to the conclusion that PhKAT probably is regulated by allosteric control machineries, with 2OG as the allosteric inhibitor.

  14. Aspartate Aminotransferase Activity after Gargling with Green Tea and Chlorhexidine Gluconate

    Directory of Open Access Journals (Sweden)

    Christian E. Suryanto

    2013-07-01

    Full Text Available Patients undergoing fixed orthodontic treatment are susceptible to dental plaque accumulation. Plaque can cause inflammation in gingiva. It could be assessed by aspartat aminotransferase (AST in gingival crevicular fluid (GCF. Mouth rinse could be useful to reduce dental plaque accumulation during orthodontic treatment. Chlorhexidine gluconate is often used as mouth rinse in dental practice. On the other hand, green tea is one of natural ingredient that can be used for mouth rinse which is assumed could reduce plaque accumulation. Objectives: To compare the effect between green tea and chlorhexidine gluconate on AST activity in GCF in patient undergoing orthodontic treatment with molar band. Methods: An experimental study was conducted included forty adult subjects. They were randomized into two groups: green tea (n=20 and chlorhexidine gluconate (n=20. AST activity was measured before band insertion, 7 and 30 days after band insertion. One way and two-ways ANOVA were used to analyze the data. Results: The results showed significant difference of AST levels between before, 7 and 30 days after band insertion in the green tea groups (p<0.05. In contrast, there was no significant differences of AST levels between before band insertion, 7 and 30 days after band insertion in the chlorhexidine gluconate groups (p=0.049. There were no difference between each groups with two way ANOVA (p<0.05. Conclusions: Gargle effect of green tea was as effective as chlorhexidine gluconate in reducing AST levels related to banded first molars in adolescents undergoing orthodontic treatment.

  15. Novel protein-protein interactions between Entamoeba histolyticad-phosphoglycerate dehydrogenase and phosphoserine aminotransferase.

    Science.gov (United States)

    Mishra, Vibhor; Kumar, Ashutosh; Ali, Vahab; Nozaki, Tomoyoshi; Zhang, Kam Y J; Bhakuni, Vinod

    2012-08-01

    Physical interactions between d-phosphoglycerate dehydrogenase (EhPGDH) and phosphoserine aminotransferase (EhPSAT) from an enteric human parasite Entamoeba histolytica was observed by pull-down assay, gel filtration chromatography, chemical cross-linking, emission anisotropy, molecular docking and molecular dynamic simulations. The protein-protein complex had a 1:1 stochiometry with a dissociation constant of 3.453 × 10(-7) M. Ionic interactions play a significant role in complex formation and stability. Analysis of the energy minimized average simulated model of the protein complex show that the nucleotide binding domain of EhPGDH specifically interacts with EhPSAT. Denaturation studies suggest that the nucleotide binding domain (Nbd) and substrate binding domain (Sbd) of EhPGDH are independent folding/unfolding units. Thus the Nbd-EhPGDH was separately cloned over-expressed and purified to homogeneity. Fluorescence anisotropy study show that the purified Nbd interacts with EhPSAT. Forward enzyme catalyzed reaction for the EhPGDH-PSAT complex showed efficient Km values for 3-phosphoglyceric acid as compared to only EhPGDH suggesting a possibility of substrate channelling in the protein complex. PMID:22386871

  16. Effects of self-association of ornithine aminotransferase on its physicochemical characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Boernke, W.E.; Stevens, F.J.; Peraino, C.

    1981-01-01

    Previous work in this laboratory has shown that the molecular weight of ornithine aminotransferase (OAT) is concentration dependent. In the present study this property of OAT was further characterized by using sedimentation equilibrium centrifugation to determine the molecular weight of OAT in a range of enzyme concentrations. It was shown that OAT aggregates in a two-stage process as its concentration increases. The first stage involves the association of enzymatically active monomers into trimers, with association of the trimmers into higher order aggregates occurring in the second stage. Decreasing the pH or raising the ionic strength enhanced aggregation, while raising the pH inhibits aggregation; however, the two-stage nature of the aggregation process was not affected by changes in pH and ionic strength. Kinetic analyses of purified enzyme showed that aggregatio results in an increase in the K/sub m/ for both substrates with the V/sub max/ remaining constant, indicating that aggregation of monomers sterically hinders substrate binding. Increased K/sub m/ values were also obtained for OAT sequestered in mitochondia from rats fed a high-protein diet to increase mitochondrial OAT levels. The higher K/sub m/ values suggest that the elevation of OAT in vivo is accompanied by aggregation of the enzyme within the mitochondrion. We propose that the aggregation-dependent increase of K/sub m/ in vivo has adaptive value in that it spares ornithine for use in the urea cycle.

  17. In vivo dosimetry with L-alpha-alanine

    Energy Technology Data Exchange (ETDEWEB)

    Boey, R.; Van Der Velden, K. [Industriele Hogeschool van het Gemeenschapsonderwijs Limburg, Hasselt (Belgium); Schaeken, B. [Algemeen Ziekenhuis Middelheim, Antwerp (Belgium). Dept. of Radiotherapy

    1995-12-01

    When organic substances are irradiated, stable electrons can be formed. The concentration of these electrons is detected via electron paramagnetic resonance (EPR), a non-destructive form of dosimetry. L-alpha-alanine is extremely suited as a detector because of its high stability and high yield of unpaired electrons. With an EMS 104 spectrometer, we measure the peak-to-peak value of the first derivate of the resonance-spectrum. This value is proportional to the concentration of unpaired electrons and therefore with the absorbed dose. Prior to the in vivo measurements in teletherapy, a calibration curve had to be established. This clearly showed a linear relationship between the EPR-signal and the absorbed dose, except for very low dose where precision was low (20% 1 sd). This indicates that the background signal of the dosimeter is strongly orientation dependent. For this reason it was decided to use pre-irradiated detectors. A number of in vivo measurements has been performed. It was found that the error propagation plays a major role in the calculation of the measured absorbed dose, in the range 1 Gy-6 Gy. Contrary to in vivo measurements in brachytherapy, where higher doses are measured, large uncertainties (30% 1 sd) on the entry dose calculations were observed. For this reason, it is recommended to use a statistical method of reducing this standard deviation to an acceptable level. The proposed method, consisting of 2 detectors and the usage of weight coefficients on our standard deviations, gave promising results. However, theoretical calculations and in vivo measurements show that this method is still not satisfactory to reduce the uncertainty to an acceptable standard in clinical situations.

  18. Solvation free energies of alanine peptides: the effect of flexibility.

    Science.gov (United States)

    Kokubo, Hironori; Harris, Robert C; Asthagiri, Dilipkumar; Pettitt, B Montgomery

    2013-12-27

    The electrostatic (ΔGel), van der Waals cavity-formation (ΔGvdw), and total (ΔG) solvation free energies for 10 alanine peptides ranging in length (n) from 1 to 10 monomers were calculated. The free energies were computed both with fixed, extended conformations of the peptides and again for some of the peptides without constraints. The solvation free energies, ΔGel, and components ΔGvdw, and ΔG, were found to be linear in n, with the slopes of the best-fit lines being γel, γvdw, and γ, respectively. Both γel and γ were negative for fixed and flexible peptides, and γvdw was negative for fixed peptides. That γvdw was negative was surprising, as experimental data on alkanes, theoretical models, and MD computations on small molecules and model systems generally suggest that γvdw should be positive. A negative γvdw seemingly contradicts the notion that ΔGvdw drives the initial collapse of the protein when it folds by favoring conformations with small surface areas. When we computed ΔGvdw for the flexible peptides, thereby allowing the peptides to assume natural ensembles of more compact conformations, γvdw was positive. Because most proteins do not assume extended conformations, a ΔGvdw that increases with increasing surface area may be typical for globular proteins. An alternative hypothesis is that the collapse is driven by intramolecular interactions. We find few intramolecular H-bonds but show that the intramolecular van der Waals interaction energy is more favorable for the flexible than for the extended peptides, seemingly favoring this hypothesis. The large fluctuations in the vdw energy may make attributing the collapse of the peptide to this intramolecular energy difficult. PMID:24328358

  19. Exercise training and beta-alanine-induced muscle carnosine loading.

    Directory of Open Access Journals (Sweden)

    Tine eBex

    2015-05-01

    Full Text Available Purpose. Beta-alanine (BA supplementation has been shown to augment muscle carnosine concentration, thereby promoting high-intensity exercise performance. Trained muscles of athletes have a higher increase in carnosine concentration after BA supplementation compared to untrained muscles, but it remains to be determined whether this is due to an accumulation of acute exercise effects or to chronic adaptations from prior training. The aim of the present study was to investigate whether high-volume (HV and/or high-intensity (HI exercise can improve BA-induced carnosine loading in untrained subjects.Methods. All participants (n=28 were supplemented with 6.4 g/day of BA for 23 days. The subjects were allocated to a control group, HV or HI training group. During the BA supplementation period, the training groups performed 9 exercise sessions consisting of either 75–90 min continuous cycling at 35–45% Wmax (HV or 3 to 5 repeats of 30s cycling at 165% Wmax with 4 min recovery (HI. Carnosine content was measured in soleus and gastrocnemius medialis by proton magnetic resonance spectroscopy.Results. There was no difference in absolute increase in carnosine content between the groups in soleus and gastrocnemius muscle. For the average muscle carnosine content, a higher absolute increase was found in HV (+ 2.95 mM; P = 0.046 and HI (+ 3.26 mM; P = 0.028 group compared to the control group (+ 1.91 mM. However, there was no additional difference between the HV and HI training group.Conclusions. HV and HI exercise training showed no significant difference on BA-induced muscle carnosine loading in soleus and gastrocnemius muscle. It can be suggested that there can be a small cumulative effect of exercise on BA supplementation efficiency, although differences did not reach significance on individual muscle level.

  20. The cross-sectional association between insulin resistance and circulating complement C3 is partly explained by plasma alanine aminotransferase, independent of central obesity and general inflammation (the CODAM study)

    NARCIS (Netherlands)

    Greevenbroek, van M.M.J.; Jacobs, M.; Kallen, van der C.J.H.; Vermeulen, V.M.M.J.; Jansen, E.H.J.M.; Schalkwijk, C.G.; Ferreira, I.; Feskens, E.J.M.; Stehouwer, C.D.A.

    2011-01-01

    P>Background Complement C3, a central component of the innate immune system is increased in subjects with obesity and type 2 diabetes and is a novel risk factor for cardiovascular disease. We hypothesized that the strong association between insulin resistance and circulating amounts of C3 may be

  1. Clinical Observation of Alanine Aminotransferase Abnormality of A Radiologist%一例放射医师丙氨酸氨基转移酶异常的临床观察

    Institute of Scientific and Technical Information of China (English)

    李长军; 李丹

    2010-01-01

    @@ 一放射医师患非酒精性脂肪性肝炎(NASH),血清丙氨酸氨基转移酶(ALT)异常,治疗效果欠佳,后从事非X线放射工作并自行停止药物治疗,观察2 a,血清ALT基本恢复正常,现予以报道.

  2. 西安地区高ALT值献血者HEV亚临床感染情况调查%Study on Hepatitis E Virus Subclinical Infection in High Alanine Aminotransferase Donors in Xi'an area

    Institute of Scientific and Technical Information of China (English)

    廖红; 陈海珊; 穆士杰; 张献清

    2013-01-01

    目的 探讨西安地区无偿献血者中戊型肝炎病毒的亚临床感染情况及其与ALT水平的相关性.方法 收集西安地区2009年1月~2010年12月ALT水平升高的1 874名无偿献血者血样,根据ALT检测结果分组后进行抗-HEVIgM和IgG、HEV RNA检测,比较各项指标间的相关性,并对HEV RNA阳性标本进行测序和基因分型.结果 1 874名无偿献血者中有7例抗-HEV IgM阳性,占0.37%;21例抗-HEV IgG阳性,占1.12%;8例HEV RNA阳性,占0.43%.其中7例抗-HEV IgM阳性者其RNA均为阳性.抗-HEV IgG的阳性率随年龄升高而增加.扩增8例HEV RNA阳性血样的保守序列ORF2分析发现5例基因型为Ⅰ型,另外3例基因型为Ⅳ型.结论 西安地区戊型肝炎病毒的亚临床感染率为0.37%,HEV流行株主要为Ⅰ型和Ⅳ型病毒株.%Objective To study the subciinical infection of hepatitis E virus of blood donors in Xi'an area, and its correlation with ALT levels. Methods To collect 1 874 blood donors samples with high ALT levels in Xi'an area from January 2009 to December 2010 and to test ALT. They were grouped according to the level of ALT. And they were detected on anti-HEV IgM and IgG, HEV RNA,then the relationships were analyzed among different indicators. The age of the donors, sequence and genotype were analyzed on the positive samples with HEV RNA. Results Among 1 874 blood donors, 7 were positive with HEV-IgM, accounting for 0. 37%, all of the seven were positive with HEV RNA. 21 were positive with HEV-IgG, accounting for 1.12%. Anti-HEV IgG positive rate increased with the age of the dolors. 8 were positive with HEV RNA, accounting for 0. 43%. HEV RNA ORF2 was amplified in 8 samples, 5 belonged to genotype I and the other 3 belonged to genotype IV. Conclusion The rate of subclinical infection of hepatitis E virus in Xi'an was 0. 37%, the genotypes of hepatitis E belonged to genotype 1 and 4.

  3. 受试者工作特征曲线评价OCT/ALT在肝细胞癌诊断中的价值%Diagnostic Value of Ornithine Carbamoyltransferase/Alanine Aminotransferase in Hepatocellular Carcinoma

    Institute of Scientific and Technical Information of China (English)

    王晓梅; 秦浩歌; 李彦姝

    2008-01-01

    目的 研究鸟氨酸氨甲酰基转移酶/丙氨酸氨基转移酶(OCT/ALT)对肝细胞癌的诊断价值.方法 测定87例肝细胞癌、75例慢性肝炎、66例肝硬化和72例健康对照者血清OCT和ALT水平,计算OCT/ALT值.并用受试者工作特征曲线(ROC)进行评价.结果 肝细胞癌组、肝炎组、肝硬化组OCT/ALT与对照组比较,差别均有统计学意义(P<0.05);肝炎组和肝硬化组OCT/ALT与肝细胞癌组比较,差别均有统计学意义(P<0.05).血清OCT/ALT的ROC下面积为0.855,OCT/ALT的最优截断点约为3.32,灵敏度和特异度分别为79.3%和87.3%.结论 通过ROC评价,血清OCT/ALT可作为鉴别诊断肝细胞癌的指标.

  4. Determination of the carbon, hydrogen and nitrogen contents of alanine and their uncertainties using the certified reference material L-alanine (NMIJ CRM 6011-a).

    Science.gov (United States)

    Itoh, Nobuyasu; Sato, Ayako; Yamazaki, Taichi; Numata, Masahiko; Takatsu, Akiko

    2013-01-01

    The carbon, hydrogen, and nitrogen (CHN) contents of alanine and their uncertainties were estimated using a CHN analyzer and the certified reference material (CRM) L-alanine. The CHN contents and their uncertainties, as measured using the single-point calibration method, were 40.36 ± 0.20% for C, 7.86 ± 0.13% for H, and 15.66 ± 0.09% for N; the results obtained using the bracket calibration method were also comparable. The method described in this study is reasonable, convenient, and meets the general requirement of having uncertainties ≤ 0.4%.

  5. SERUM ACTIVITIES OF ASPARTATE AMINOTRANSFERASE, CREATINE KINASE AND LACTATE DEHYDROGENASE IN HORSES WITH COLIC ATIVIDADE SÉRICA DAS ENZIMAS ASPARTATO AMINOTRANSFERASE, CREATINA QUINASE E LACTATO DESIDROGENASE EM EQÜINOS COM CÓLICA

    OpenAIRE

    Aureo Evangelista Santana; Paula Alessandra Di Filippo

    2008-01-01

    Seventy equines distributed in two experimental groups were used, G1 (20 healthy equines), and G2 (50 equines with colic). Blood samples were obtained by jugular vein puncture in ten different moments. The variables aspartate aminotransferase (AST), creatine kinase (CK), and lactate dehydrogenase (LDH) were determined by spectrophotometric assay using specific reagents. The average values presented by the animals of the G2 for variables CK, AST, and LDH were higher (P<0.05) than the values...

  6. Substrate Specificity of the Aspartate:Alanine Antiporter (AspT) of Tetragenococcus halophilus in Reconstituted Liposomes*

    OpenAIRE

    Sasahara, Ayako; Nanatani, Kei; Enomoto, Masaru; Kuwahara, Shigefumi; Abe, Keietsu

    2011-01-01

    The aspartate:alanine antiporter (AspT) of the lactic acid bacterium Tetragenococcus halophilus is a member of the aspartate:alanine exchanger (AAEx) transporter family. T. halophilus AspT catalyzes the electrogenic exchange of l-aspartate1− with l-alanine0. Although physiological functions of AspT were well studied, l-aspartate1−:l-alanine0 antiport mechanisms are still unsolved. Here we report that the binding sites of l-aspartate and l-alanine are independently present in AspT by means of ...

  7. Eukaryotic beta-alanine synthases are functionally related but have a high degree of structural diversity

    DEFF Research Database (Denmark)

    Gojkovic, Zoran; Sandrini, Michael; Piskur, Jure

    2001-01-01

    activity was used to clone analogous genes from different eukaryotes. Putative PYD3 sequences from the yeast S. kluyveri, the slime mold Dictyostelium discoideum, and the fruit fly Drosophila melanogaster complemented the pyd3 defect. When the S. kluyveri PYD3 gene was expressed in S. cerevisiae, which has...... no pyrimidine catabolic pathway, it enabled growth on N-carbamyl- beta -alanine as the sole nitrogen source. The D. discoideum and D. melanogaster PYD3 gene products are similar to mammalian beta -alanine synthases. In contrast, the S. kluyveri protein is quite different from these and more similar to bacterial......-carbamyl-beta -alanine, but not by uracil. This wrork establishes S. kluyveri as a model organism for studying pyrimidine degradation and beta -alanine production in eukaryotes....

  8. Crystallization and preliminary X-ray study of alkaline alanine racemase from Bacillus pseudofirmus OF4

    OpenAIRE

    Ju, Jiansong; Qi, Jianxun; Xu, Shujing; Ohnishi, Kouhei; Benedik, Michael J.; Xue, Yanfen; Ma, Yanhe

    2009-01-01

    An alkaline alanine racemase from alkaliphilic B. pseudofirmus OF4 was expressed in E. coli and purified. Crystallization and preliminarily X-­ray crystallographic analysis were performed for the recombinant enzyme.

  9. SYNTHESIS OF D-AND L-β-(4-CHLOROPHENYL)-α-ALANINE

    Institute of Scientific and Technical Information of China (English)

    沈宗璇; 张雅文; 顾德本; 滕洪流; 杨冰

    1991-01-01

    N-acetyl-β-(4-chloropheayl)-DL-α-alanine ethyl ester was synthesized from p-chlorobenzyl chloride via diethyl malonate method. The ethyl ester was effectively resofued by enzymatic hydrolysis with using of subtilisin carlsberg.

  10. Second harmonic generation studies in L-alanine single crystals grown from solution

    International Nuclear Information System (INIS)

    Single crystals of L-alanine of dimensions 2×1.1×0.5 cm3 were grown by evaporation method using deionised water as a solvent. The morphology of the grown crystals had (1 2 0) and (0 1 1) as their prominent faces. UV–vis-near IR spectrum shows the transparency range of L-alanine crystal available for frequency doubling from 250 to 1400 nm. Phase-matched second harmonic generation was observed in L-alanine sample by using 7 ns Q-switched Nd:YAG laser with OPO set up. In the present work, phase matching was achieved by angle and wavelength tuning. The angular and spectral phase-matching bandwidths were determined experimentally for a 1.5 mm thick L-alanine crystal and the results have been compared with their theoretical results. Further the possible reasons for the broadening of SHG spectrum have been discussed

  11. ESR investigation of L-α-alanine and sucrose radicals produced by heavy-ion irradiation

    International Nuclear Information System (INIS)

    We investigated sucrose and L-α-alanine radicals produced by heavy ion irradiation with various LETs (linear energy transfer). The impact of the heavy ions on the samples produced stable free radicals, which were analyzed by ESR (electron spin resonance). The obtained spectral patterns were the same as those for carbon (C), neon (Ne), and silicon (Si) ion irradiations. The absorbed dose dependences for the irradiated sucrose and alanine samples were examined. The ESR response has a linear relation with the absorbed dose for both compounds. In addition, the total spin concentration obtained by heavy-ion irradiation correlated logarithmically with the LET. Let Qualitative ESR analyses showed that the production of sucrose and alanine radical depended on both different particle irradiation and the LET under the same dose. Thus, the present ESR results imply that sucrose together with L-α-alanine can be used to investigate radical production processes induced by ionizing particles. (author)

  12. Enzymatic determination of carbon-14 labeled L-alanine in biological samples

    International Nuclear Information System (INIS)

    A method for determination of L-alanine-specific radioactivity in biological samples is presented. This method is based on the specific enzymatic transformation of L-alanine to pyruvic acid hydrazone catalyzed by the enzyme L-alanine dehydrogenase, formation of the pyruvic acid 2,4-dinitrophenylhydrazone derivative, and quantitative trapping in Amberlite XAD-7 columns, followed by radioactivity counting of the lipophilic eluate. No interferences from other 14C-labeled materials such as D-glucose, glycerol, L-lactate, L-serine, L-glutamate, L-phenylalanine, glycine, L-leucine, and L-arginine were observed. This inexpensive and high-speed method is applicable to the simultaneous determination of L-alanine-specific radioactivity for a large number of samples

  13. Dosimetry of electron and gamma radiation with alanine/ESR spectroscopy

    International Nuclear Information System (INIS)

    A new method for the preparation of alanine dosimeters was investigated. The absorbed dose response of these dosimeters was demonstrated for 10 MeV electron and 60Co gamma radiation in the range from 20 Gy to 1.1 kGy. Concentration of the irradiation-induced free radicals in the alanine was determined by ESR spectroscopy. In addition to measurements at ambient temperature, the alanine dosimeters were also subjected to thermal treatment during irradiation (up to about 50 deg. C) in order to assess their performance characteristics under extreme conditions which might arise in future technical applications. The results show that under normal conditions the alanine calibration curves are linear, whereas at higher temperatures the dosimeters require a correction of 0.3%/K for absorbed doses above 200 Gy. (author)

  14. Enzymatic determination of carbon-14 labeled L-alanine in biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Serra, F.; Palou, A.; Pons, A.

    1987-07-15

    A method for determination of L-alanine-specific radioactivity in biological samples is presented. This method is based on the specific enzymatic transformation of L-alanine to pyruvic acid hydrazone catalyzed by the enzyme L-alanine dehydrogenase, formation of the pyruvic acid 2,4-dinitrophenylhydrazone derivative, and quantitative trapping in Amberlite XAD-7 columns, followed by radioactivity counting of the lipophilic eluate. No interferences from other UC-labeled materials such as D-glucose, glycerol, L-lactate, L-serine, L-glutamate, L-phenylalanine, glycine, L-leucine, and L-arginine were observed. This inexpensive and high-speed method is applicable to the simultaneous determination of L-alanine-specific radioactivity for a large number of samples.

  15. Purification, crystallization and preliminary X-ray crystallographic analysis of branched-chain aminotransferase from Deinococcus radiodurans

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Chung-Der; Huang, Tien-Feng [Department of Physics, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Lin, Chih-Hao [Institute of Biological Chemistry, National Taiwan University, Taipei 110,Taiwan (China); Guan, Hong-Hsiang; Hsieh, Yin-Cheng [Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China); Institute of Bioinformatics and Structural Biology, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Lin, Yi-Hung; Huang, Yen-Chieh; Liu, Ming-Yih [Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China); Chang, Wen-Chang, E-mail: wchang@ntu.edu.tw [Institute of Biological Chemistry, National Taiwan University, Taipei 110,Taiwan (China); Chen, Chun-Jung, E-mail: wchang@ntu.edu.tw [Department of Physics, National Tsing-Hua University, Hsinchu 30013,Taiwan (China); Life Science Group, Research Division, National Synchrotron Radiation Research Center, Hsinchu 30076,Taiwan (China)

    2007-06-01

    The crystallization of branched-chain aminotransferase from D. radiodurans is described. The branched-chain amino-acid aminotransferase (BCAT), which requires pyridoxal 5′-phosphate (PLP) as a cofactor, is a key enzyme in the biosynthetic pathway of the hydrophobic amino acids leucine, isoleucine and valine. DrBCAT from Deinococcus radiodurans, which has a molecular weight of 40.9 kDa, was crystallized using the hanging-drop vapour-diffusion method. According to X-ray diffraction data to 2.50 Å resolution from a DrBCAT crystal, the crystal belongs to space group P2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 56.37, b = 90.70, c = 155.47 Å. Preliminary analysis indicates the presence of two DrBCAT molecules in the asymmetric unit, with a solvent content of 47.52%.

  16. The influence of measurement and storage conditions on alanine ESR dosimeters

    International Nuclear Information System (INIS)

    Alanine has several desirable properties as an ESR dosemeter e.g. tissue equivalence, low fading and an approximately linear response for doses up to 10 kGy. This work reports on a simple system to produce the alanine dosemeter, the signal intensity for a range of doses and energies, and the effect of the air humidity and the spectrometer settings on the ESR signal. (Author)

  17. Muscle carnosine metabolism and β-alanine supplementation in relation to exercise and training

    OpenAIRE

    Derave, Wim; Everaert, Inge; Beeckman, Sam; Baguet, Audrey

    2010-01-01

    Carnosine is a dipeptide with a high concentration in mammalian skeletal muscle. It is synthesized by carnosine synthase from the amino acids L-histidine and beta-alanine, of which the latter is the rate-limiting precursor, and degraded by carnosinase. Recent studies have shown that the chronic oral ingestion of beta-alanine can substantially elevate (up to 80%) the carnosine content of human skeletal muscle. Interestingly, muscle carnosine loading leads to improved performance in high-intens...

  18. Dosimetry for radiation processing of wire insulations by using the alanine/ESR system

    International Nuclear Information System (INIS)

    The wire insulation can be simulated by an alanine-based dosimeter, i.e. by a polymer containing L-α-alanine. If this system is properly calibrated against a reliable reference dosimeter, it can be used to determine the absorbed dose in the wire insulation, irradiated on an industrial line for electron-beam crosslinking of wire insulations. The evaluation is achieved by ESR spectroscopy. (author) 13 refs.; 3 figs

  19. Polarographic (d.c. and a.c.) behaviour of vanadium-DL-α-alanine complexes

    International Nuclear Information System (INIS)

    A detailed investigation of the d.c. polarographic behaviour of vanadium(V), and (III) and the a.c. polarographic behaviour of vanadium(IV) in α-alanine solution has been made keeping the total α-alanine concentration at 0.1,0.5 and 1.0M and varying the pH of the solution. (M.G.B.)

  20. EPR dosimetry of radiotherapy photon beams in inhomogeneous media using alanine films.

    Science.gov (United States)

    Osterås, Bjørn Helge; Hole, Eli Olaug; Olsen, Dag Rune; Malinen, Eirik

    2006-12-21

    In the current work, EPR (electron paramagnetic resonance) dosimetry using alanine films (134 microm thick) was utilized for dose measurements in inhomogeneous phantoms irradiated with radiotherapy photon beams. The main phantom material was PMMA, while either Styrofoam or aluminium was introduced as an inhomogeneity. The phantoms were irradiated to a maximum dose of about 30 Gy with 6 or 15 MV photons. The performance of the alanine film dosimeters was investigated and compared to results from ion chamber dosimetry, Monte Carlo simulations and radiotherapy treatment planning calculations. It was found that the alanine film dosimeters had a linear dose response above approximately 5 Gy, while a background signal obscured the response at lower dose levels. For doses between 5 and 60 Gy, the standard deviation of single alanine film dose estimates was about 2%. The alanine film dose estimates yielded results comparable to those from the Monte Carlo simulations and the ion chamber measurements, with absolute differences between estimates in the order of 1-15%. The treatment planning calculations exhibited limited applicability. The current work shows that alanine film dosimetry is a method suitable for estimating radiotherapeutical doses and for dose measurements in inhomogeneous media. PMID:17148820

  1. EPR dosimetry of radiotherapy photon beams in inhomogeneous media using alanine films

    Energy Technology Data Exchange (ETDEWEB)

    Oesteraas, Bjoern Helge [Department of Radiation Biology, Institute for Cancer Research, Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway); Hole, Eli Olaug [Department of Physics, University of Oslo, PO Box 1048 Blindern, N-0316 Oslo (Norway); Olsen, Dag Rune [Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway); Malinen, Eirik [Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo (Norway)

    2006-12-21

    In the current work, EPR (electron paramagnetic resonance) dosimetry using alanine films (134 {mu}m thick) was utilized for dose measurements in inhomogeneous phantoms irradiated with radiotherapy photon beams. The main phantom material was PMMA, while either Styrofoam or aluminium was introduced as an inhomogeneity. The phantoms were irradiated to a maximum dose of about 30 Gy with 6 or 15 MV photons. The performance of the alanine film dosimeters was investigated and compared to results from ion chamber dosimetry, Monte Carlo simulations and radiotherapy treatment planning calculations. It was found that the alanine film dosimeters had a linear dose response above approximately 5 Gy, while a background signal obscured the response at lower dose levels. For doses between 5 and 60 Gy, the standard deviation of single alanine film dose estimates was about 2%. The alanine film dose estimates yielded results comparable to those from the Monte Carlo simulations and the ion chamber measurements, with absolute differences between estimates in the order of 1-15%. The treatment planning calculations exhibited limited applicability. The current work shows that alanine film dosimetry is a method suitable for estimating radiotherapeutical doses and for dose measurements in inhomogeneous media.

  2. Synthesis of silver nanoparticles using DL-alanine for ESR dosimetry applications

    International Nuclear Information System (INIS)

    The potential use of alanine for the production of nanoparticles is presented here for the first time. Silver nanoparticles were synthesized using a simple green method, namely the thermal treatment of silver nitrate aqueous solutions with DL-alanine. The latter compound was employed both as a reducing and a capping agent. Particles with average size equal to 7.5 nm, face-centered cubic crystalline structure, narrow size distribution, and spherical shape were obtained. Interaction between the silver ions present on the surface of the nanoparticles and the amine group of the DL-alanine molecule seems to be responsible for reduction of the silver ions and for the stability of the colloid. The bio-hybrid nano-composite was used as an ESR dosimeter. The amount of silver nanoparticles in the nanocomposite was not sufficient to cause considerable loss of tissue equivalency. Moreover, the samples containing nanoparticles presented increased sensitivity and reduced energetic dependence as compared with pure DL-alanine, contributing to the construction of small-sized dosimeters. - Highlights: ► The synthesis is environmentally benign, easy to perform, and of low-cost. ► DL-Alanine was employed both as reducing and capping agent. ► Mean size of 7.5 nm, narrow size distribution, and spherical shape of particles. ► Increased sensitivity and reduced energetic dependence compared with pure alanine. ► The nanocomposite has potential application for ESR dosimetry.

  3. An efficient protocol for the complete incorporation of methyl-protonated alanine in perdeuterated protein

    International Nuclear Information System (INIS)

    A strategy for the introduction of (1H,13C-methyl)-alanine into perdeuterated proteins is described. Specific protonation of alanine methyl groups to a level of 95% can be achieved by overexpressing proteins in M9/D2O based bacterial growth medium supplemented with 800 mg/l of 2-[2H], 3-[13C] l-alanine. However, though simple, this approach results in undesired, non-specific background labeling due to isotope scrambling via different amino acid metabolic pathways. Following a careful analysis of known metabolic pathways we found that co-addition of perdeuterated forms of α-ketoisovalerate-d7, succinate-d4 and l-isoleucine-d10 with labeled l-alanine, reduces undesired background labeling to <1%. When combined with recently developed methyl TROSY experiments, this methyl-specific labeling protocol permits the acquisition of excellent quality correlation spectra of alanine methyl groups in high molecular weight proteins. Our cost effective strategy offers a significant enhancement in the level of incorporation of methyl-labeled alanine in overexpressed proteins over previously reported methods

  4. [Alanine solution as enzyme reaction buffer used in A to O blood group conversion].

    Science.gov (United States)

    Li, Su-Bo; Zhang, Xue; Zhang, Yin-Ze; Tan, Ying-Xia; Bao, Guo-Qiang; Wang, Ying-Li; Ji, Shou-Ping; Gong, Feng; Gao, Hong-Wei

    2014-06-01

    The aim of this study was to investigate the effect of alanine solution as α-N-acetylgalactosaminidase enzyme reaction buffer on the enzymatic activity of A antigen. The binding ability of α-N-acetylgalactosaminidase with RBC in different reaction buffer such as alanine solution, glycine solution, normal saline (0.9% NaCl), PBS, PCS was detected by Western blot. The results showed that the efficiency of A to O conversion in alanine solution was similar to that in glycine solution, and Western blot confirmed that most of enzymes blinded with RBC in glycine or alanine solution, but few enzymes blinded with RBC in PBS, PCS or normal saline. The evidences indicated that binding of enzyme with RBC was a key element for A to O blood group conversion, while the binding ability of α-N-acetylgalactosaminidase with RBC in alanine or glycine solution was similar. It is concluded that alanine solution can be used as enzyme reaction buffer in A to O blood group conversion. In this buffer, the α-N-acetylgalactosaminidase is closely blinded with RBC and α-N-acetylgalactosaminidase plays efficient enzymatic activity of A antigen.

  5. Averaged electron collision cross sections for thermal mixtures of $\\alpha$-Alanine conformers in the gas phase

    CERN Document Server

    Fujimoto, Milton M; Tennyson, Jonathan

    2016-01-01

    A theoretical study of elastic electron collisions with 9 conformers of the gas-phase amino acid $\\alpha$-alanine (CH$_3$CH(NH$_2$)COOH) is performed. The eigenphase sums, resonance features, differential and integral cross sections are computed for each individual conformer. Resonance positions for the low-energy $\\pi^*$ shape resonance are found to vary from 2.6 eV to 3.1 eV and the resonance widths from 0.3 eV to 0.5 eV. Averaged cross sections for thermal mixtures of the 9 conformers are presented. Both theoretical and experimental population ratios are considered. Thermally-averaged cross sections obtained using the best theoretical estimates give reasonable agreement with the observed thermal cross sections. Excited conformers IIA and IIB make a large contribution to this average due to their large permanent dipole moments.

  6. Overexpression, purification and crystallization of lysine ∊-aminotransferase (Rv3290c) from Mycobacterium tuberculosis H37Rv

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, Sarvind Mani; Ramachandran, Ravishankar, E-mail: ravi-anitha@yahoo.com [Molecular and Structural Biology Division, Central Drug Research Institute, PO Box 173, Chattar Manzil, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2006-06-01

    Lysine ∊-aminotransferase from M. tuberculosis has been crystallized. Preliminary crystallographic analysis shows that there is one monomer in the asymmetric unit of the crystal. Lysine ∊-aminotransferase (LAT) is a protein involved in lysine catabolism; it belongs to the aminotransferase family of enzymes, which use pyridoxal 5′-phosphate (PLP) as a cofactor. LAT probably plays a significant role during the persistent/latent phase of Mycobacterium tuberculosis, as observed by its up-regulation by ∼40-fold during this stage. Crystals of recombinant LAT have been grown in 0.1 M trisodium citrate dihydrate solution containing 0.2 M ammonium acetate and 25% PEG 4000 in the pH range 5.4–6.0. Diffraction data extending to 1.98 Å were collected at room temperature from a single crystal. Crystals are trigonal in shape and belong to space group P3{sub 1}21, with unit-cell parameters a = 103.26, b = 103.26, c = 98.22 Å. The crystals contain a monomer in the asymmetric unit, which corresponds to a Matthews coefficient (V{sub M}) of 3.1 Å{sup 3} Da{sup −1}.

  7. Branched-Chain Aminotransferases Control TORC1 Signaling in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Joanne M Kingsbury

    2015-12-01

    Full Text Available The conserved target of rapamycin complex 1 (TORC1 integrates nutrient signals to orchestrate cell growth and proliferation. Leucine availability is conveyed to control TORC1 activity via the leu-tRNA synthetase/EGOC-GTPase module in yeast and mammals, but the mechanisms sensing leucine remain only partially understood. We show here that both leucine and its α-ketoacid metabolite, α-ketoisocaproate, effectively activate the yeast TORC1 kinase via both EGOC GTPase-dependent and -independent mechanisms. Leucine and α-ketoisocaproate are interconverted by ubiquitous branched-chain aminotransferases (BCAT, which in yeast are represented by the mitochondrial and cytosolic enzymes Bat1 and Bat2, respectively. BCAT yeast mutants exhibit severely compromised TORC1 activity, which is partially restored by expression of Bat1 active site mutants, implicating both catalytic and structural roles of BCATs in TORC1 control. We find that Bat1 interacts with branched-chain amino acid metabolic enzymes and, in a leucine-dependent fashion, with the tricarboxylic acid (TCA-cycle enzyme aconitase. BCAT mutation perturbed TCA-cycle intermediate levels, consistent with a TCA-cycle block, and resulted in low ATP levels, activation of AMPK, and TORC1 inhibition. We propose the biosynthetic capacity of BCAT and its role in forming multicomplex metabolons connecting branched-chain amino acids and TCA-cycle metabolism governs TCA-cycle flux to activate TORC1 signaling. Because mammalian mitochondrial BCAT is known to form a supramolecular branched-chain α-keto acid dehydrogenase enzyme complex that links leucine metabolism to the TCA-cycle, these findings establish a precedent for understanding TORC1 signaling in mammals.

  8. Novel and recurrent tyrosine aminotransferase gene mutations in tyrosinemia type II.

    Science.gov (United States)

    Hühn, R; Stoermer, H; Klingele, B; Bausch, E; Fois, A; Farnetani, M; Di Rocco, M; Boué, J; Kirk, J M; Coleman, R; Scherer, G

    1998-03-01

    Tyrosinemia type II (Richner-Hanhart syndrome, RHS) is a disorder of autosomal recessive inheritance characterized by keratitis, palmoplantar hyperkeratosis, mental retardation, and elevated blood tyrosine levels. The disease results from deficiency in hepatic tyrosine aminotransferase (TAT). We have previously described one deletion and six different point mutations in four RHS patients. We have now analyzed the TAT genes in a further seven unrelated RHS families from Italy, France, the United Kingdom, and the United States. We have established PCR conditions for the amplification of all twelve TAT exons and have screened the products for mutations by direct sequence analysis or by first performing single-strand conformation polymorphism analysis. We have thus identified the presumably pathological mutations in eight RHS alleles, including two nonsense mutations (R57X, E411X) and four amino acid substitutions (R119W, L201R, R433Q, R433W). Only the R57X mutation, which was found in one Scottish and two Italian families, has been previously reported in another Italian family. Haplotype analysis indicates that this mutation, which involves a CpG dinucleotide hot spot, has a common origin in the three Italian families but arose independently in the Scottish family. Two polymorphisms have also been detected, viz., a protein polymorphism, P15S, and a silent substitution S103S (TCG-->TCA). Expression of R433Q and R433W demonstrate reduced activity of the mutant proteins. In all, twelve different TAT gene mutations have now been identified in tyrosinemia type II.

  9. L,L-diaminopimelate aminotransferase from Chlamydomonas reinhardtii: a target for algaecide development.

    Directory of Open Access Journals (Sweden)

    Renwick C J Dobson

    Full Text Available In some bacterial species and photosynthetic cohorts, including algae, the enzyme L,L-diaminopimelate aminotransferase (DapL (E.C. 2.6.1.83 is involved in the anabolism of the essential amino acid L-lysine. DapL catalyzes the conversion of tetrahydrodipicolinate (THDPA to L,L-diaminopimelate (L,L-DAP, in one step bypassing the DapD, DapC and DapE enzymatic reactions present in the acyl DAP pathways. Here we present an in vivo and in vitro characterization of the DapL ortholog from the alga Chlamydomonas reinhardtii (Cr-DapL. The in vivo analysis illustrated that the enzyme is able to functionally complement the E. coli dap auxotrophs and was essential for plant development in Arabidopsis. In vitro, the enzyme was able to inter-convert THDPA and L,L-DAP, showing strong substrate specificity. Cr-DapL was dimeric in both solution and when crystallized. The structure of Cr-DapL was solved in its apo form, showing an overall architecture of a α/β protein with each monomer in the dimer adopting a pyridoxal phosphate-dependent transferase-like fold in a V-shaped conformation. The active site comprises residues from both monomers in the dimer and shows some rearrangement when compared to the apo-DapL structure from Arabidopsis. Since animals do not possess the enzymatic machinery necessary for the de novo synthesis of the amino acid L-lysine, enzymes involved in this pathway are attractive targets for the development of antibiotics, herbicides and algaecides.

  10. Relaxed evolution in the tyrosine aminotransferase gene tat in old world fruit bats (Chiroptera: Pteropodidae.

    Directory of Open Access Journals (Sweden)

    Bin Shen

    Full Text Available Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae and two New World fruit bats (Phyllostomidae. Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet.

  11. Relaxed evolution in the tyrosine aminotransferase gene tat in old world fruit bats (Chiroptera: Pteropodidae).

    Science.gov (United States)

    Shen, Bin; Fang, Tao; Yang, Tianxiao; Jones, Gareth; Irwin, David M; Zhang, Shuyi

    2014-01-01

    Frugivorous and nectarivorous bats fuel their metabolism mostly by using carbohydrates and allocate the restricted amounts of ingested proteins mainly for anabolic protein syntheses rather than for catabolic energy production. Thus, it is possible that genes involved in protein (amino acid) catabolism may have undergone relaxed evolution in these fruit- and nectar-eating bats. The tyrosine aminotransferase (TAT, encoded by the Tat gene) is the rate-limiting enzyme in the tyrosine catabolic pathway. To test whether the Tat gene has undergone relaxed evolution in the fruit- and nectar-eating bats, we obtained the Tat coding region from 20 bat species including four Old World fruit bats (Pteropodidae) and two New World fruit bats (Phyllostomidae). Phylogenetic reconstructions revealed a gene tree in which all echolocating bats (including the New World fruit bats) formed a monophyletic group. The phylogenetic conflict appears to stem from accelerated TAT protein sequence evolution in the Old World fruit bats. Our molecular evolutionary analyses confirmed a change in the selection pressure acting on Tat, which was likely caused by a relaxation of the evolutionary constraints on the Tat gene in the Old World fruit bats. Hepatic TAT activity assays showed that TAT activities in species of the Old World fruit bats are significantly lower than those of insectivorous bats and omnivorous mice, which was not caused by a change in TAT protein levels in the liver. Our study provides unambiguous evidence that the Tat gene has undergone relaxed evolution in the Old World fruit bats in response to changes in their metabolism due to the evolution of their special diet.

  12. Inhibition of kynurenine aminotransferase II reduces activity of midbrain dopamine neurons.

    Science.gov (United States)

    Linderholm, Klas R; Alm, Maximilian Tufvesson; Larsson, Markus K; Olsson, Sara K; Goiny, Michel; Hajos, Mihaly; Erhardt, Sophie; Engberg, Göran

    2016-03-01

    Kynurenic acid (KYNA), a neuroactive metabolite of tryptophan, is elevated in the brain of patients with psychotic disorders. Therefore, lowering brain KYNA levels might be a novel approach in the treatment of psychotic disorders. The present in vivo electrophysiological study aimed to investigate the effect of an inhibitor of kynurenine aminotransferase (KAT) II, the primary enzyme for KYNA synthesis, on dopamine (DA) neurons in the ventral tegmental area (VTA). Acute administration of the KAT II inhibitor PF-04859989 (5 or 10 mg/kg) was associated with a short-onset, time-dependent decrease in firing rate and burst activity of DA neurons, both parameters reaching a 50% reduction within 45 min. Furthermore, PF-04859989 reduced the number of spontaneously active DA cells as measured 4-6 after administration. Pretreatment with d-cycloserine (30 mg/kg) or CGP-52432 (10 mg/kg) prevented the inhibitory action of PF-04859989 (5 mg/kg) on firing rate and burst firing activity. In contrast, pretreatment with methyllycaconitine (MLA, 4 mg/kg) did not change the response, whereas picrotoxin (4.5 mg/kg) partially prevented the inhibitory effects of PF-04859989 (5 mg/kg, i.v.). Our results show that a specific inhibition of KAT II is associated with a marked reduction in VTA DA firing activity. This effect appears to be specifically executed by NMDA-receptors and mediated indirectly via a GABA(B)-receptor-induced disinhibition of DA neurons. Our findings are in line with the view that endogenous KYNA, by modulation of the NMDA-receptor, exerts important physiological roles in the brain.

  13. Studies of the uptake and release of [3H]β-alanine by frog spinal slices

    International Nuclear Information System (INIS)

    [3H]β-alanine was accumulated by frog spinal cord slices by two transport components with estimated Ksub(m) values of μM ('high-affinity') and 11 mM ('low affinity') respectively. The high affinity uptake exhibited sodium ion and energy dependence, temperature sensitivity, had a very low Vsub(max) (10.4 nmol/g/min) compared to GABA and glycine, was competitively inhibited by GABA (Ksub(i) 2μM), and was significantly reduced by the presence of glycine and of taurine in the incubating medium. When slices preloaded with [3H]β-alanine were superfused with medium containing depolarizing concentrations of potassium ions, there was a small, but consistent, increase in [3H]β-alanine efflux: 1.4 times prestimulation rates in 40 mM potassium. When the superfusate was altered by omission of calcium and addition of concentrations of magnesium (10 mM), manganese (1 mM), and cobalt (1 mM) ions sufficient to block reflex transmission in the isolated in vitro frog cord, the potassium-evoked release was not blocked. Release was decreased by lanthanum ions (1 mM). Release of [3H]GABA and [3H]glycine in parallel experiments was inhibited by magnesium, manganese, cobalt and lanthanum. Veratridine significantly increased the release of [3H]GABA and [3H]glycine but not of [3H]β-alanine. These observations demonstrate the non-specificity of β-alanine uptake and the unconventional nature of the calcium-dependence of β-alanine release and therefore do not lend support to the hypothesis that β-alanine functions as a neurotransmitter in frog spinal cord. (author)

  14. Perturbation correction for alanine dosimeters in different phantom materials in high-energy photon beams

    Science.gov (United States)

    von Voigts-Rhetz, P.; Anton, M.; Vorwerk, H.; Zink, K.

    2016-02-01

    In modern radiotherapy the verification of complex treatments plans is often performed in inhomogeneous or even anthropomorphic phantoms. For dose verification small detectors are necessary and therefore alanine detectors are most suitable. Though the response of alanine for a wide range of clinical photon energies in water is well know, the knowledge about the influence of the surrounding phantom material on the response of alanine is sparse. Therefore we investigated the influence of twenty different surrounding/phantom materials for alanine dosimeters in clinical photon fields via Monte Carlo simulations. The relative electron density of the used materials was in the range {{n}e}/{{n}e,\\text{w}}=0.20 up to 1.69, covering almost all materials appearing in inhomogeneous or anthropomorphic phantoms used in radiotherapy. The investigations were performed for three different clinical photon spectra ranging from 6 to 25 MV-X and Co-60 and as a result a perturbation correction {{k}\\text{env}} depending on the environmental material was established. The Monte Carlo simulation show, that there is only a small dependence of {{k}\\text{env}} on the phantom material and the photon energy, which is below  ±0.6%. The results confirm the good suitability of alanine detectors for in-vivo dosimetry.

  15. Effect of 10 Week Beta-Alanine Supplementation on Competition and Training Performance in Elite Swimmers

    Directory of Open Access Journals (Sweden)

    Louise M. Burke

    2012-10-01

    Full Text Available Although some laboratory-based studies show an ergogenic effect with beta-alanine supplementation, there is a lack of field-based research in training and competition settings. Elite/Sub-elite swimmers (n = 23 males and 18 females, age = 21.7 ± 2.8 years; mean ± SD were supplemented with either beta-alanine (4 weeks loading phase of 4.8 g/day and 3.2 g/day thereafter or placebo for 10 weeks. Competition performance times were log-transformed, then evaluated before (National Championships and after (international or national selection meet supplementation. Swimmers also completed three standardized training sets at baseline, 4 and 10 weeks of supplementation. Capillary blood was analyzed for pH, bicarbonate and lactate concentration in both competition and training. There was an unclear effect (0.4%; ±0.8%, mean, ±90% confidence limits of beta-alanine on competition performance compared to placebo with no meaningful changes in blood chemistry. While there was a transient improvement on training performance after 4 weeks with beta-alanine (−1.3%; ±1.0%, there was an unclear effect at ten weeks (−0.2%; ±1.5% and no meaningful changes in blood chemistry. Beta-alanine supplementation appears to have minimal effect on swimming performance in non-laboratory controlled real-world training and competition settings.

  16. Effect of β-alanine supplementation on 20 km cycling time trial performance

    Directory of Open Access Journals (Sweden)

    Ruth Margaret JAMES

    2014-09-01

    Full Text Available The effects of β-alanine supplementation on high-intensity cycling performance and capacity have been evaluated, although the effects on longer duration cycling performance are unclear. Nineteen UK category 1 male cyclists completed four 20 km cycling time trials, two before and two after supplementation with either 6.4 g•d-1 β-alanine (n = 10; BA or a matched placebo (n = 9; P. Performance time for the 20 km time trial and 1 km split times were recorded. There was no significant effect of β-alanine supplementation on 20 km time trial performance (BA-pre 1943 ± 129 s; BA-post 1950 ± 147 s; P-pre 1989 ± 106 s; P-post 1986 ± 115 s or on the performance of each 1 km split. The effect of β-alanine on 20 km time trial performance was deemed unclear as determined by magnitude based inferences. Supplementation with 6.4 g•d-1 of β-alanine for 4 weeks did not affect 20 km cycling time trial performance in well trained male cyclists.

  17. ESR investigation of L-α-alanine and sucrose radicals produced by heavy-ion irradiation

    International Nuclear Information System (INIS)

    We investigated sucrose and L-α-alanine radicals produced by heavy (particle) ion irradiation with various LETs (linear energy transfer). The impact of the heavy ions on the samples produced stable free radicals, which were analyzed by ESR (electron spin resonance). Identical spectra were measured after one year. The obtained spectral patterns were the same as those for helium (He), carbon (C), and neon (Ne) ions irradiation. The absorbed dose dependences for the irradiated sucrose and alanine samples were examined. The ESR response has a linear relation with the absorbed dose. The ESR response at 60 Gy was slightly lower than a linear line for sucrose; however, the response showed good linearity for the alanine. In addition, the total spin concentration obtained by heavy-ion irradiation correlated logarithmically with the LET. Qualitative ESR analyse showed that the production of sucrose and alanine radicals depended on both different particle irradiation and the LET under the same dose. Thus, the present ESR results imply that sucrose together with L-α-alanine can be used to monitor LET as well as the number of ionizing particle for the production of stable free radicals. (author)

  18. Substrate specificity of the aspartate:alanine antiporter (AspT) of Tetragenococcus halophilus in reconstituted liposomes.

    Science.gov (United States)

    Sasahara, Ayako; Nanatani, Kei; Enomoto, Masaru; Kuwahara, Shigefumi; Abe, Keietsu

    2011-08-19

    The aspartate:alanine antiporter (AspT) of the lactic acid bacterium Tetragenococcus halophilus is a member of the aspartate:alanine exchanger (AAEx) transporter family. T. halophilus AspT catalyzes the electrogenic exchange of L-aspartate(1-) with L-alanine(0). Although physiological functions of AspT were well studied, L-aspartate(1-):L-alanine(0) antiport mechanisms are still unsolved. Here we report that the binding sites of L-aspartate and L-alanine are independently present in AspT by means of the kinetic studies. We purified His(6)-tagged T. halophilus AspT and characterized its kinetic properties when reconstituted in liposomes (K(m) = 0.35 ± 0.03 mm for L-aspartate, K(m) = 0.098 ± 0 mm for D-aspartate, K(m) = 26 ± 2 mm for L-alanine, K(m) = 3.3 ± 0.2 mm for D-alanine). Competitive inhibition by various amino acids of L-aspartate or L-alanine in self-exchange reactions revealed that L-cysteine selectively inhibited L-aspartate self-exchange but only weakly inhibited L-alanine self-exchange. Additionally, L-serine selectively inhibited L-alanine self-exchange but barely inhibited L-aspartate self-exchange. The aspartate analogs L-cysteine sulfinic acid, L-cysteic acid, and D-cysteic acid competitively and strongly inhibited L-aspartate self-exchange compared with L-alanine self-exchange. Taken together, these kinetic data suggest that the putative binding sites of L-aspartate and L-alanine are independently located in the substrate translocation pathway of AspT. PMID:21719707

  19. Substrate Specificity of the Aspartate:Alanine Antiporter (AspT) of Tetragenococcus halophilus in Reconstituted Liposomes*

    Science.gov (United States)

    Sasahara, Ayako; Nanatani, Kei; Enomoto, Masaru; Kuwahara, Shigefumi; Abe, Keietsu

    2011-01-01

    The aspartate:alanine antiporter (AspT) of the lactic acid bacterium Tetragenococcus halophilus is a member of the aspartate:alanine exchanger (AAEx) transporter family. T. halophilus AspT catalyzes the electrogenic exchange of l-aspartate1− with l-alanine0. Although physiological functions of AspT were well studied, l-aspartate1−:l-alanine0 antiport mechanisms are still unsolved. Here we report that the binding sites of l-aspartate and l-alanine are independently present in AspT by means of the kinetic studies. We purified His6-tagged T. halophilus AspT and characterized its kinetic properties when reconstituted in liposomes (Km = 0.35 ± 0.03 mm for l-aspartate, Km = 0.098 ± 0 mm for d-aspartate, Km = 26 ± 2 mm for l-alanine, Km = 3.3 ± 0.2 mm for d-alanine). Competitive inhibition by various amino acids of l-aspartate or l-alanine in self-exchange reactions revealed that l-cysteine selectively inhibited l-aspartate self-exchange but only weakly inhibited l-alanine self-exchange. Additionally, l-serine selectively inhibited l-alanine self-exchange but barely inhibited l-aspartate self-exchange. The aspartate analogs l-cysteine sulfinic acid, l-cysteic acid, and d-cysteic acid competitively and strongly inhibited l-aspartate self-exchange compared with l-alanine self-exchange. Taken together, these kinetic data suggest that the putative binding sites of l-aspartate and l-alanine are independently located in the substrate translocation pathway of AspT. PMID:21719707

  20. The background of the total synthesis of yeast alanine transfer RNA

    Institute of Scientific and Technical Information of China (English)

    QI GuoRong

    2010-01-01

    @@ The research findings concerning the total synthesis of yeast alanine transfer RNA (yeast alanine tRNA) were successively published in Chinese Science Bulletin (1982) and Science in China (1983) [1].The research work started in 1968 and was finished in November 1981.It was the first artificial synthesis of a nucleic acid molecule, which followed the first artificial synthesis of protein, crystalline bovine insulin, in China in 1965, both scientific milestones occurring in China.The composition, sequence and biological functions of the synthesized nucleic acid were identical to those of the natural yeast alanine tRNA.The research lasted for 13 years.From 1982 to 1984, one of the investigators in charge of the research Prof.

  1. Combined TL and 10B-alanine ESR dosimetry for BNCT.

    Science.gov (United States)

    Bartolotta, A; D'Oca, M C; Lo Giudice, B; Brai, M; Borio, R; Forini, N; Salvadori, P; Manera, S

    2004-01-01

    The dosimetric technique described in this paper is based on electron spin resonance (ESR) detectors using an alanine-boric compound acid enriched with (10)B, and beryllium oxide thermoluminescent (TL) detectors; with this combined dosimetry, it is possible to discriminate the doses due to thermal neutrons and gamma radiation in a mixed field. Irradiations were carried out inside the thermal column of a TRIGA MARK II water-pool-type research nuclear reactor, also used for Boron Neutron Capture therapy (BNCT) applications, with thermal neutron fluence from 10(9) to 10(14) nth cm(-2). The ESR dosemeters using the alanine-boron compound indicated ESR signals about 30-fold stronger than those using only alanine. Moreover, a negligible correction for the gamma contribution, measured with TL detectors, almost insensitive to thermal neutrons, was necessary. Therefore, a simultaneous analysis of our TL and ESR detectors allows discrimination between thermal neutron and gamma doses, as required in BNCT. PMID:15353720

  2. Applicability of EPR/alanine dosimetry for quality assurance in proton eye radiotherapy.

    Science.gov (United States)

    Michalec, B; Mierzwinska, G; Ptaszkiewicz, M; Sowa, U; Stolarczyk, L; Weber, A

    2014-06-01

    A new quality assurance and quality control method for proton eye radiotherapy based on electron paramagnetic resonance (EPR)/alanine dosimetry has been developed. It is based on Spread-Out Bragg Peak entrance dose measurement with alanine detectors. The entrance dose is well correlated with the dose at the facility isocenter, where, during the therapeutic irradiation, the tumour is placed. The unique alanine detector features namely keeping the dose record in a form of stable radiation-induced free radicals trapped in the material structure, and the non-destructive read-out makes this type of detector a good candidate for additional documentation of the patient's exposure over the therapy course. PMID:24876341

  3. The application of Alanine/ESR dosimetry in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hoon; Lee, Byung Il [Radiation Health Research Institute, Seoul (Korea, Republic of)

    2014-05-15

    Alanine/Electron spin resonance(ESR) has been proven very effective tool which dosimetric characteristics is better suitable than generally used personnel dosimeter for long term dose estimation. L-α-alanine has unusual stability of radiation induced radicals. The fading is known as about 1% a year by IAEA technical documentary. It also has linear signal response on gamma rays over the wide range of dose quantity. Alanine is a kind of unnecessary amino acid in 20 amino acids. Estimation of the accumulated gamma dose is important to predict the life expectancy of cables. However, exact estimation of gamma dose at containment building of NPP is very difficult, because the variability of estimation value is apparently depending on the each installation position in containment building. Especially, some installation positions near reactor change extremely. So, the data from ESR measurement should be checked to the details on referring installation map and pictures.

  4. ESR/L-alanine system as a proposed standard dosimeter for electron-beam irradiations

    International Nuclear Information System (INIS)

    The ESR/L-alanine system is a promising dosimeter, as it is characterized by high precision, stable dosimetric response, low value of G(freeradical) and non-toxicity. The scattering and absorption of γ radiation and fast electrons are equivalent for the system, for soft biological tissues, and for water. The possibility of further standardizations of the alanine dosimeter has now been proposed, not only as previously for γ radiation, but also for high-energy electron beam processing which brings high dose rates and side-effect problems. On the basis of the experimental results it seems reasonable to propose a new and more precise approximation of the functional shape describing the response of the L-alanine dosimeter and to express it directly by the radiation chemical yield of free radicals. (author)

  5. ESR/L-alanine system as a proposed standard dosimeter for electron-beam irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Panta, P.P.; Strzelczak-Burlinska, G.; Tomasinski, Z. (Institute of Nuclear Chemistry and Technology, Warsaw (Poland))

    1989-01-01

    The ESR/L-alanine system is a promising dosimeter, as it is characterized by high precision, stable dosimetric response, low value of G{sub (free} {sub radical)} and non-toxicity. The scattering and absorption of {gamma} radiation and fast electrons are equivalent for the system, for soft biological tissues, and for water. The possibility of further standardizations of the alanine dosimeter has now been proposed, not only as previously for {gamma} radiation, but also for high-energy electron beam processing which brings high dose rates and side-effect problems. On the basis of the experimental results it seems reasonable to propose a new and more precise approximation of the functional shape describing the response of the L-alanine dosimeter and to express it directly by the radiation chemical yield of free radicals. (author).

  6. Radiation chemistry of L-Alanine: application to EPR dosimetry (1)

    International Nuclear Information System (INIS)

    High energy ionizing radiation leaves stable radicals to certain organic materials, such as alanine and tartrate. Electron Paramagnetic Resonance (EPR) spectroscopy is a powerful tool for the identification and quantification of these radiation-induced radicals. An EPR method has been applied to study the radical characteristics of L-alanine after gamma radiation dose in the range of ∼mGy to 60 kGy. The free radicals induced by gamma radiation were fairly stable, and EPR intensity, radical concentration, was proportional to the absorbed dose up to 60 kGy. From the results of our EPR measurements, it can be concluded that an alanine/EPR method is a useful technique for gamma radiation dosimetry from very low to high dose range

  7. 14N nuclear quadrupole interaction in Cu(II) doped L-alanine

    International Nuclear Information System (INIS)

    The 14N nuclear quadrupole interaction tensor Psub(N) measured by ENDOR in Cu(II) doped L-alanine is analyzed in terms of the Townes and Daily theory assuming a tetra-hedrally bonded N atom. The results of this analysis are compared with those for the 14N in pure L-alanine and it is found that the principal directions of the Psub(N) tensor are drastically changed upon metal complexation as a consequence of the higher electron affinity of Cu(II) with respect to C and H. Comparison of the corresponding bond populations in pure and Cu(II) doped L-alanine indicates that the Cu draws 0.11 more electron from the N than the substituted H atom. (orig.)

  8. Adsorption of L-Alanine on Cu(111) Studied by Scanning Tunnelling Microscopy

    Institute of Scientific and Technical Information of China (English)

    GE Si-Ping; L(U) Chao; ZHAO Ru-Guang

    2006-01-01

    The adsorption of L-alanine on Cu(111)surface is studied by means of scanning tunnelling microscopy under ultra-high Vacuum conditions.The results show that the adsorbates are chemisorbed on the surface,and can form a two-dimensional gas phase,chain phase and solid phase,depending on deposition rate and amount.The adsorbed molecules can be imaged as individual protrusions and parallel chains in gas and chain phases respectively.It is also found that alanine can form(2×2)superstructure on Cu(111)and copper step facet to directions in solid phase.On the basis of our scanning tunnelling microscopic images,a model js proposed for the Cu(111)(2×2)-alanine superstructure.In the model,we point out the close link between -direction hydrogen bond chains with the same direction copper step faceting.

  9. Structure of Penta-Alanine Investigated by Two-Dimensional Infrared Spectroscopy and Molecular Dynamics Simulation.

    Science.gov (United States)

    Feng, Yuan; Huang, Jing; Kim, Seongheun; Shim, Ji Hyun; MacKerell, Alexander D; Ge, Nien-Hui

    2016-06-23

    We have studied the structure of (Ala)5, a model unfolded peptide, using a combination of 2D IR spectroscopy and molecular dynamics (MD) simulation. Two different isotopomers, each bis-labeled with (13)C═O and (13)C═(18)O, were strategically designed to shift individual site frequencies and uncouple neighboring amide-I' modes. 2D IR spectra taken under the double-crossed ⟨π/4, -π/4, Y, Z⟩ polarization show that the labeled four-oscillator systems can be approximated by three two-oscillator systems. By utilizing the different polarization dependence of diagonal and cross peaks, we extracted the coupling constants and angles between three pairs of amide-I' transition dipoles through spectral fitting. These parameters were related to the peptide backbone dihedral angles through DFT calculated maps. The derived dihedral angles are all located in the polyproline-II (ppII) region of the Ramachandran plot. These results were compared to the conformations sampled by Hamiltonian replica-exchange MD simulations with three different CHARMM force fields. The C36 force field predicted that ppII is the dominant conformation, consistent with the experimental findings, whereas C22/CMAP predicted similar population for α+, β, and ppII, and the polarizable Drude-2013 predicted dominating β structure. Spectral simulation based on MD representative conformations and structure ensembles demonstrated the need to include multiple 2D spectral features, especially the cross-peak intensity ratio and shape, in structure determination. Using 2D reference spectra defined by the C36 structure ensemble, the best spectral simulation is achieved with nearly 100% ppII population, although the agreement with the experimental cross-peak intensity ratio is still insufficient. The dependence of population determination on the choice of reference structures/spectra and the current limitations on theoretical modeling relating peptide structures to spectral parameters are discussed. Compared

  10. The effect of β-alanine supplementation on cycling time trials of different length.

    Science.gov (United States)

    Bellinger, Phillip M; Minahan, Clare L

    2016-10-01

    The varying results reported in response to β-alanine supplementation may be related to the duration and nature of the exercise protocol employed. We investigated the effects of β-alanine supplementation on a wide range of cycling performance tests in order to produce a clear concise set of criteria for its efficacy. Fourteen trained cyclists (Age = 24.8 ± 6.7 years; VO2max = 65.4 ± 10.2 mL·kg·min(-1)) participated in this placebo-controlled, double-blind study. Prior to supplementation, subjects completed two (familiarization and baseline) supramaximal cycling bouts until exhaustion (120% pre-supplementation VO2max) and two 1-, 4- and 10-km cycling time trial (TT). Subjects then supplemented orally for 4 weeks with 6.4 g/d placebo or β-alanine and repeated the battery of performance tests. Blood lactate was measured pre-exercise, post-exercise and 5  min post-exercise. β-alanine supplementation elicited significant increases in time to exhaustion (TTE) (17.6 ± 11.5 s; p = 0.013, effect compared with placebo) and was likely to be beneficial to 4-km TT performance time (-7.8 ± 8.1 s; 94% likelihood), despite not being statistically different (p = 0.060). Performance times in the 1- and 10-km TT were not affected by treatment. For the highly trained cyclists in the current study, β-alanine supplementation significantly extended supramaximal cycling TTE and may have provided a worthwhile improvement to 4-km TT performance. However, 1- and 10-km cycling TT performance appears to be unaffected by β-alanine supplementation. PMID:26652037

  11. Radical formation of irradiated α-alanine and N-acetyl alanine with heavy ion beams. Effects of the irradiation temperature

    International Nuclear Information System (INIS)

    The characteristics of irradiation with C290 MeV/u ion beams were investigated using X-band electron spin resonance (ESR) spectroscopy for a polycrystalline powder of L-α-alanine at from 77K to 310K. The formed main radicals at 190K∼310K were the deamino radical and the decarboxyl radical. Because of the first-derivative ESR, decarboxyl radical showed an expanded spectral width and a lower peak height because of its amino hydrogen and nitrogen than that of the same amount of deamino radical. The ESR of irradiated L-α-alanine predominantly indicates the spectrum of the deamino radical. On the irradiated, L-α-alanine at from 77K to 310K ESR showed 1:4:6:4:1 lines at 220K and at room temperature, which indicate that the methyl group of the radical was rotating. On the other hand, at 77K ESR the spectrum showed nearly 1:5:5:5:1 lines, like the teeth of a saw, on samples irradiated at 270K∼350K (range IV), and 1:4:6:4:1 lines for those irradiated at 180K∼260K (range II and III), respectively. It is considered that the radical conformation of the deamino radical is planar (most stable conformation) on an irradiated sample in range IV, and a pyramidal structure on the irradiated sample in ranges II and III. (author)

  12. Effects of β-alanine supplementation and high-intensity interval training on endurance performance and body composition in men; a double-blind trial

    Directory of Open Access Journals (Sweden)

    Beck Travis W

    2009-02-01

    Full Text Available Abstract Background Intermittent bouts of high-intensity exercise result in diminished stores of energy substrates, followed by an accumulation of metabolites, promoting chronic physiological adaptations. In addition, β-alanine has been accepted has an effective physiological hydrogen ion (H+ buffer. Concurrent high-intensity interval training (HIIT and β-alanine supplementation may result in greater adaptations than HIIT alone. The purpose of the current study was to evaluate the effects of combining β-alanine supplementation with high-intensity interval training (HIIT on endurance performance and aerobic metabolism in recreationally active college-aged men. Methods Forty-six men (Age: 22.2 ± 2.7 yrs; Ht: 178.1 ± 7.4 cm; Wt: 78.7 ± 11.9; VO2peak: 3.3 ± 0.59 l·min-1 were assessed for peak O2 utilization (VO2peak, time to fatigue (VO2TTE, ventilatory threshold (VT, and total work done at 110% of pre-training VO2peak (TWD. In a double-blind fashion, all subjects were randomly assigned into one either a placebo (PL – 16.5 g dextrose powder per packet; n = 18 or β-alanine (BA – 1.5 g β-alanine plus 15 g dextrose powder per packet; n = 18 group. All subjects supplemented four times per day (total of 6 g/day for the first 21-days, followed by two times per day (3 g/day for the subsequent 21 days, and engaged in a total of six weeks of HIIT training consisting of 5–6 bouts of a 2:1 minute cycling work to rest ratio. Results Significant improvements in VO2peak, VO2TTE, and TWD after three weeks of training were displayed (p 2peak, VO2TTE, TWD and lean body mass were only significant for the BA group after the second three weeks of training. Conclusion The use of HIIT to induce significant aerobic improvements is effective and efficient. Chronic BA supplementation may further enhance HIIT, improving endurance performance and lean body mass.

  13. Active Oxygen Radical Scavenging Ability of Water-Soluble β-Alanine C60 Adducts

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Water-soluble β-alanine C60 adducts were synthesized, and the scavenging ability to superoxygen anion radical O2-and hydroxyl radicalOH were studied by autoxidation ofpyrogallol and chemiluminescence, respectively. It was found that β-alanine C60 adducts showed an excellent efficiency in eliminating superoxygen anion radical and hydroxyl radical. The 50% inhibition concentration (IC50) for superoxygen anion radical and hydroxyl radical were 0.15 mg/mL and 0.048 mg/mL, respectively. The difference should be mainly attributed to the different scavenging mechanisms.

  14. Standard Enthalpies of Formation of Solid Complexes of Lanthanide Nitrates with Alanine

    Institute of Scientific and Technical Information of China (English)

    杨旭武; 陈三平; 高胜利; 刘晓华; 史启祯

    2002-01-01

    The combustion energies of fourteen solid complexes of lanthanide nitrate with alanine were determined. The standard enthalpies of combustion, Δc,coor(s)H°, and standard enthalpies of formation, Δf,coor(s)H°, were calculated for these complexes. The relationship of Δc,coor(s)H° and Δf,coor(s)H° with the atomic numbers of the elements in the lanthanide series were examined. The results show that a certain amount of covalence is present in the chemical bond between the lanthanide cations and alanine.

  15. Synthesis, Characterization and Metal Ion Detection of Novel Fluoroionophores Based on Heterocyclic Substituted Alanines

    Directory of Open Access Journals (Sweden)

    M. Manuela M Raposo

    2007-10-01

    Full Text Available The synthesis of new fluorescent probes containing the thiophene andbenzoxazole moieties combined with an alanine residue is described. The resulting highlyfluorescent heterocyclic alanine derivatives respond via a quenching effect, withparamagnetic Cu(II and Ni(II metal ions and with diamagnetic Hg(II, as shown by theabsorption and steady-state fluorescence spectroscopy studies. The formation ofmononuclear or dinuclear metal complexes was postulated based on the presence of thefree carboxylic acid as binding site and also with the interaction with the donor atoms inthe chromophore. Interaction with other important biological metal ions such as Zn(II,Ca(II and Na(I was also explored.

  16. Dose response and fading characteristics of an alanine-agarose gel

    International Nuclear Information System (INIS)

    The dose response of an alanine-agarose gel, analyzed by ESR spectrometry, and the stability of the radiation-induced free radicals have been investigated. The stability of the ESR signal is higher for dosimeter samples analyzed at 77 K than for dried samples, analyzed at room-temperature. The dose response is linear to within ±2% in the absorbed dose interval 2-100 Gy. The variations in spectral line shape were analyzed at temperatures between 77 and 270 K. The experimental ESR spectrum at 77 K was compared with a simulated spectrum of polycrystals of L-α-alanine. (Author)

  17. EPR study of the annealing effects on the x-ray-irradiated l-alanine

    International Nuclear Information System (INIS)

    L-alanine has been discovered to be one of the best emergency dosimetric materials. In this research, the dosimetric properties of L-alanine were re-examined using an electron paramagnetic resonance (EPR) spectrometer. The intensities of the EPR signal were measured at room temperature after a 30-minute annealing at various temperatures. We investigated the annealing effect on the samples for various temperatures in the range from -10 .deg. C to 50 .deg. C by using EPR. These intensities depend on the areal, daily,and seasonal temperatures

  18. A spectrophotometric readout for γ irradiated alanine solution - a dosimetric application

    International Nuclear Information System (INIS)

    Alanine is a stable dosimeter of reference in its solid state. Its installation in solution as being a dosimetric system of routine remains very useful. A follow-up of the behaviour of the irradiated alanine solution with 15 kGy according to the concentration is carried out by UV-Visible spectrophotometry. The results obtained prove the difficulty in analytical studies of the radiolysis of aqueous solutions by optical absorption due to the ambiguous broad spectra of the species and the reaction products. (Author). 47 refs

  19. On the Helix-coil Transition in Alanine-based Polypeptides in Gas Phase

    CERN Document Server

    Wei, Y; Hansmann, U H E

    2007-01-01

    Using multicanonical simulations, the authors study the effect of charged end groups on helix formation in alanine based polypeptides. They confirm earlier reports that neutral polyalanine exhibits a pronounced helix-coil transition in gas phase simulations. Introducing a charged Lys+ at the C terminal stabilizes the helix and leads to a higher transition temperature. On the other hand, adding the Lys+ at the N terminal inhibits helix formation. Instead, a more globular structure was found. These results are in agreement with recent experiments on alanine based polypeptides in gas phase. They indicate that present force fields describe accurately the intramolecular interactions in proteins.

  20. Crystallization and preliminary X-ray diffraction analysis of l,l-diaminopimelate aminotransferase (DapL) from Chlamydomonas reinhardtii

    International Nuclear Information System (INIS)

    A variant of the diaminopimelate/lysine pathway has recently been defined following the discovery of the enzyme l,l-diaminopimelate aminotransferase (DapL). The cloning of the cDNA, recombinant expression, purification and preliminary diffraction analysis of DapL from the alga C. reinhardtii are presented. In the anabolic synthesis of diaminopimelate and lysine in plants and in some bacteria, the enzyme l,l-diaminopimelate aminotransferase (DapL; EC 2.6.1.83) catalyzes the conversion of tetrahydrodipicolinic acid (THDPA) to l,l-diaminopimelate, bypassing the DapD, DapC and DapE enzymatic steps in the bacterial acyl pathways. Here, the cloning, expression, purification, crystallization and preliminary X-ray diffraction analysis of DapL from the alga Chlamydomonas reinhardtii are presented. Protein crystals were grown in conditions containing 25%(w/v) PEG 3350 and 200 mM lithium sulfate and initially diffracted to ∼1.35 Å resolution. They belonged to space group P212121, with unit-cell parameters a = 58.9, b = 91.8, c = 162.9 Å. The data were processed to 1.55 Å resolution with an Rmerge of 0.081, an Rp.i.m. of 0.044, an Rr.i.m of 0.093 and a VM of 2.28 Å3 Da−1

  1. The effect of isotretinoin on triglycerides and liver aminotransferases Influência da isotretinoína nas transaminases hepáticas e triglicerídeos

    Directory of Open Access Journals (Sweden)

    Andreia Salezze Vieira

    2012-06-01

    Full Text Available BACKGROUND: Isotretinoin has been used to treat the most severe cases of acne; however, it may provoke adverse events in mucocutaneous and hepatic tissues, lead to alterations in lipid levels and cause teratogenicity. OBJECTIVE: The objective of this study was to evaluate the profile of changes in alanine aminotransferase (ALT, aspartate aminotransferase (AST and triglyceride levels in patients who had been treated with oral isotretinoin dispensed by the São Mateus/ES pharmacy for special drugs. METHODS: A retrospective, observational, longitudinal study was conducted by carrying out a secondary analysis of each patient's data. RESULTS: Of the 130 patients who received isotretinoin between January and December 2009, only 70 were actually treated for 3 months or more and handed in the results of their laboratory tests. Of these 70 patients, 39 (55.7% were female. The mean age of the women (23.9 years was higher than the mean age of the men (20.1 years. There was a statistically significant increase in the levels of triglycerides (87.01 ± 48.25 versus 105.32 ± 48.76 mg/dL, AST (20.44 ± 6.26 versus 24.38 ± 11.92 U/L and ALT (18.24 ± 8.31 versus 23.34 ± 20.03 U/L performed prior to and 3 months or more after oral isotretinoin treatment. After treatment with oral isotretinoin, triglyceride levels had increased beyond the normal range in 11% of the patients, while 8.6% had elevated AST levels and 7.3% had increased ALT levels. CONCLUSION: The results in this population show that the use of oral isotretinoin for the treatment of acne may result in altered triglyceride, AST and ALT levels. These findings are in accordance with data published previously in the scientific literature, confirming the need to monitor these patients.FUNDAMENTOS: A isotretinoína tem sido usada no tratamento dos casos mais graves de acne, embora possa induzir reações adversas nos tecidos mucocutâneos e hepáticos, alterações nos níveis lipídicos e

  2. Comparison of the tyrosine aminotransferase cDNA and genomic DNA sequences of normal mink and mink affected with tyrosinemia type II.

    Science.gov (United States)

    Leib, S R; McGuire, T C; Prieur, D J

    2005-01-01

    Type II tyrosinemia, designated Richner-Hanhart syndrome in humans, is a hereditary metabolic disorder with autosomal recessive inheritance characterized by a deficiency of tyrosine aminotransferase activity. Mutations occur in the human tyrosine aminotransferase gene, resulting in high levels of tyrosine and disease. Type II tyrosinemia occurs in mink, and our hypothesis was that it would also be associated with mutation(s) in the tyrosine aminotransferase gene. Therefore, the transcribed cDNA and the genomic tyrosine aminotransferase gene were sequenced from normal and affected mink. The gene extended over 11.9 kb and had 12 exons coding for a predicted 454-amino-acid protein with 93% homology with human tyrosine aminotransferase. FISH analysis mapped the gene to chromosome 8 using the Mandahl and Fredga (1975) nomenclature and chromosome 5 using the Christensen et al. (1996) nomenclature. The hypothesis was rejected because sequence analysis disclosed no mutations in either cDNA or introns that were associated with affected mink. This suggests that an unlinked gene regulatory mutation may be the cause of tyrosinemia in mink.

  3. Probing the interaction of the amino acid alanine with the surface of ZnO(1010).

    Science.gov (United States)

    Gao, Y K; Traeger, F; Shekhah, O; Idriss, H; Wöll, C

    2009-10-01

    The adsorption modes and stability of the amino acid alanine (NH(2)-CH(CH(3))-COOH) have been studied on the nonpolar single crystal surface of zinc oxide, ZnO(1010), experimentally by X-ray photoelectron spectroscopy (XPS) and computationally using density functional theory (DFT). Deposition at 200 K was found to lead to the formation of multilayers identified by an XPS N1s peak at 401.7 eV assigned to the NH(3)(+) group, a fingerprint of the zwitterionic structure of alanine in the solid state. Heating to 300 K resulted in the removal of most of the multilayers with the remaining surface coverage estimated to 0.4 with respect to Zn cations. At this temperature most of the alanine molecules are found to be deprotonated (dissociated), yielding a carboxylate species (NH(2)-CH(CH(3))-COO(-) (a) + OH (s); where O is surface oxygen, (a) for adsorbed and (s) for surface species). Further heating of the surface resulted in a gradual decrease of the surface coverage and by 500 K a large fraction of adsorbed alanine molecules have desorbed from the surface. Total energy DFT computations of different adsorbate species identified two stable dissociative adsorption modes: bidentate and monodentate. The bidentate species with adsorption energy of 1.75 eV was found to be more stable than the monodentate species by about 0.7 eV.

  4. Fragmentation of alpha- and beta-alanine molecules by ions at Bragg-peak energies

    NARCIS (Netherlands)

    Bari, S.; Sobocinski, P.; Postma, J.; Alvarado, F.; Hoekstra, R.; Bernigaud, V.; Manil, B.; Rangama, J.; Huber, B.; Schlathoelter, T.

    2008-01-01

    The interaction of keV He(+), He(2+), and O(5+) ions with isolated alpha and beta isomers of the amino acid alanine was studied by means of high resolution coincidence time-of-flight mass spectrometry. We observed a strong isomer dependence of characteristic fragmentation channels which manifests in

  5. On the fragmentation of biomolecules: fragmentation of alanine dipeptide along the polypeptide chain

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Yakubovich, Alexander; Solov'yov, Andrey;

    2006-01-01

    The interaction potential between amino acids in alanine dipeptide has been studied for the first time taking into account exact molecular geometry. Ab initio calculation has been performed in the framework of density functional theory taking into account all electrons in the system. The fragment...

  6. High-pressure X-ray diffraction of L-ALANINE crystal

    DEFF Research Database (Denmark)

    Olsen, J.S.; Gerward, Leif; Souza, A.G.;

    2006-01-01

    L-ALANINE has been studied by X-ray diffraction at ambient temperature and pressure up to 10.3 GPa. The material is found to transform to a tetragonal structure between 2 and 3 GPa. and to a monoclinic structure between 8 and 10 GPa. The experimental bulk modulus is 25(5) GPa for the orthorhombic...

  7. Yeast beta-alanine synthase shares a structural scaffold and origin with dizinc-dependent exopeptidases

    DEFF Research Database (Denmark)

    Lundgren, S.; Gojkovic, Zoran; Piskur, Jure;

    2003-01-01

    beta-Alanine synthase (betaAS) is the final enzyme of the reductive pyrimidine catabolic pathway, which is responsible for the breakdown of pyrimidine bases, including several anticancer drugs. In eukaryotes, betaASs belong to two subfamilies, which exhibit a low degree of sequence similarity. We...

  8. Probing the interaction of the amino acid alanine with the surface of ZnO(1010).

    Science.gov (United States)

    Gao, Y K; Traeger, F; Shekhah, O; Idriss, H; Wöll, C

    2009-10-01

    The adsorption modes and stability of the amino acid alanine (NH(2)-CH(CH(3))-COOH) have been studied on the nonpolar single crystal surface of zinc oxide, ZnO(1010), experimentally by X-ray photoelectron spectroscopy (XPS) and computationally using density functional theory (DFT). Deposition at 200 K was found to lead to the formation of multilayers identified by an XPS N1s peak at 401.7 eV assigned to the NH(3)(+) group, a fingerprint of the zwitterionic structure of alanine in the solid state. Heating to 300 K resulted in the removal of most of the multilayers with the remaining surface coverage estimated to 0.4 with respect to Zn cations. At this temperature most of the alanine molecules are found to be deprotonated (dissociated), yielding a carboxylate species (NH(2)-CH(CH(3))-COO(-) (a) + OH (s); where O is surface oxygen, (a) for adsorbed and (s) for surface species). Further heating of the surface resulted in a gradual decrease of the surface coverage and by 500 K a large fraction of adsorbed alanine molecules have desorbed from the surface. Total energy DFT computations of different adsorbate species identified two stable dissociative adsorption modes: bidentate and monodentate. The bidentate species with adsorption energy of 1.75 eV was found to be more stable than the monodentate species by about 0.7 eV. PMID:19596338

  9. Probing the stability of nonglycosylated wild-type erythropoietin protein via reiterative alanine ligations

    OpenAIRE

    Brailsford, John A.; Danishefsky, Samuel J.

    2012-01-01

    Nonglycosylated erythropoietin bearing acetamidomethyl protecting groups at the cysteine residues has been synthesized via chemical methods. Alanine ligation was used to assemble four peptide fragments, themselves prepared by solid phase peptide synthesis. This work outlines a route for the synthesis of homogeneous glycosylated erythropoietin.

  10. Study of EPR spectra of radicals from ionizing radiation interaction with alanine and 4-hydroxyproline samples

    International Nuclear Information System (INIS)

    A number of stable chemical radicals result following irradiation with ionizing rays of α-β-alanine and 4-hydroxyproline. They could be put into evidence using post-irradiation EPR technique. Analysis and inter-comparison of spectra signals become important for a correct assignment of structure and, subsequently of generating mechanisms in amino acids irradiated samples. (author)

  11. Alanine ESR dosimetry as a travelling dosimetric system for intercomparison purposes

    Energy Technology Data Exchange (ETDEWEB)

    Bartolotta, A. (Palermo Univ. (Italy). Ist. di Fisica); Onori, S.; Pantaloni, M. (Istituto Superiore di Sanita, Rome (Italy). Lab. di Fisica)

    1990-01-01

    The major features of the ESR alanine dosimetry set up at the ISS are discussed, with particular regards to those aspects which render it suitable as travelling dosimetric system, both for photon and electron beams. The main results of an intercomparison program among the routine dosimetric systems used at the Italian industrial irradiation plants are shown.

  12. Electron paramagnetic resonance radiation dosimetry: possible inorganic alternatives to the EPR/alanine dosimeter

    International Nuclear Information System (INIS)

    The intensity of the EPR spectrum of γ-irradiated L-α-alanine has been accepted by the International Atomic Energy Agency as a secondary standard for high-dose (10-100 000 Gy) dosimetry. The alanine dosimeter is not without its disadvantages, however, and in this article alternative EPR dosimeters are explored. These include SO3- in irradiated K2CH2(SO3)2 and CO2- in irradiated sodium formate (NaHCO2), both of which have some advantages over CH3CHCO2- in L-α-alanine. Using as a readout parameter the peak-to-peak excursion of the strongest line, these systems have a four-fold sensitivity advantage over alanine. The radicals SO3- and CO2- are, moreover, found in a wide variety of matrices, and it may be possible to find one in which they are even stronger. The need to discover a dosimeter material sensitive enough to function in the 'clinical' dose range (below 10 Gy) is emphasized. (author)

  13. Electron paramagnetic resonance radiation dosimetry: possible inorganic alternatives to the EPR/alanine dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Keizer, P.N.; Morton, J.R.; Preston, K.F. (National Research Council of Canada, Ottawa, ON (Canada). Steacie Inst. for Molecular Sciences)

    1991-10-07

    The intensity of the EPR spectrum of {gamma}-irradiated L-{alpha}-alanine has been accepted by the International Atomic Energy Agency as a secondary standard for high-dose (10-100 000 Gy) dosimetry. The alanine dosimeter is not without its disadvantages, however, and in this article alternative EPR dosimeters are explored. These include SO{sub 3}{sup -} in irradiated K{sub 2}CH{sub 2}(SO{sub 3}){sub 2} and CO{sub 2}{sup -} in irradiated sodium formate (NaHCO{sub 2}), both of which have some advantages over CH{sub 3}CHCO{sub 2}{sup -} in L-{alpha}-alanine. Using as a readout parameter the peak-to-peak excursion of the strongest line, these systems have a four-fold sensitivity advantage over alanine. The radicals SO{sub 3}{sup -} and CO{sub 2}{sup -} are, moreover, found in a wide variety of matrices, and it may be possible to find one in which they are even stronger. The need to discover a dosimeter material sensitive enough to function in the 'clinical' dose range (below 10 Gy) is emphasized. (author).

  14. Effect of alpha interferon on glucose and alanine transport by rat renal brush border membrane vesicles

    International Nuclear Information System (INIS)

    To investigate the pathogenetic mechanisms of interferon nephrotoxicity, we studied the effect of recombinant interferon alfa-2b on the uptake of 14C-D-glucose and 14C-L-alanine by rat renal brush-border-membrane vesicles. Interferon significantly inhibited 20 sec. sodium-dependent and 5 and 10 min. equilibrium uptake of both glucose and alanine. The inhibitory effect was dose dependent with maximum effect achieved at interferon concentration of 5 x 10-8M in the uptake media. The half-maximal inhibitory concentrations, IC50, of interferon on glucose uptake was 1.8 x 10-8M, and 5.4 x 10-9M on alanine uptake. Dixon plot analysis of uptake data was consistent with pure non-competitive inhibition. The inhibition constants, Ki, 1.5 x 10-8M for glucose uptake, and 7.3 x 10-9M for alanine uptake, derived from Dixon plots were in close agreement with the IC50s calculated from the semilog dose response curves. These observations reveal that direct interactions at the proximal tubule cell membrane are involved in the pathogenesis of interferon nephrotoxicity, and that its mechanism of nephrotoxicity is similar to that of other low molecular weight proteins

  15. Mechanism of inactivation of alanine racemase by beta, beta, beta-trifluoroalanine

    International Nuclear Information System (INIS)

    The alanine racemases are a group of PLP-dependent bacterial enzymes that catalyze the racemization of alanine, providing D-alanine for cell wall synthesis. Inactivation of the alanine racemases from the Gram-negative organism Salmonella typhimurium and Gram-positive organism Bacillus stearothermophilus with beta, beta, beta-trifluoroalanine has been studied. The inactivation occurs with the same rate constant as that for formation of a broad 460-490-nm chromophore. Loss of two fluoride ions per mole of inactivated enzyme and retention of [1-14C]trifluoroalanine label accompany inhibition, suggesting a monofluoro enzyme adduct. Partial denaturation (1 M guanidine) leads to rapid return of the initial 420-nm chromophore, followed by a slower (t1/2 approximately 30 min-1 h) loss of the fluoride ion and 14CO2 release. At this point, reduction by NaB3H4 and tryptic digestion yield a single radiolabeled peptide. Purification and sequencing of the peptide reveals that lysine-38 is covalently attached to the PLP cofactor. A mechanism for enzyme inactivation by trifluoroalanine is proposed and contrasted with earlier results on monohaloalanines, in which nucleophilic attack of released aminoacrylate on the PLP aldimine leads to enzyme inactivation. For trifluoroalanine inactivation, nucleophilic attack of lysine-38 on the electrophilic beta-difluoro-alpha, beta-unsaturated imine provides an alternative mode of inhibition for these enzymes

  16. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    Science.gov (United States)

    Vela, T.; Selvarajan, P.; Freeda, T. H.; Balasubramanian, K.

    2013-04-01

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV-visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated.

  17. Growth and characterization of pure and semiorganic nonlinear optical Lithium Sulphate admixtured l-alanine crystal

    International Nuclear Information System (INIS)

    Lithium sulphate admixtured l-alanine (LSLA) salt was synthesized and the solubility of the commercially available l-alanine and the synthesized LSLA sample was determined in de-ionized water at various temperatures. In accordance with the solubility data, the saturated aqueous solutions of l-alanine and lithium admixtured l-alanine were prepared separately and the single crystals of the samples were grown by the solution method with a slow evaporation technique. Studying single x-ray diffraction shows that pure and LSLA crystal belong to the orthorhombic system with a non-centrosymmetric space group P212121. Using the powder x-ray diffraction study, the crystallinity of the grown crystals is confirmed and the diffraction peaks are indexed. The various functional groups present in the pure and LSLA crystal are elucidated from Fourier transform infrared spectroscopy study. UV–visible transmittance is recorded to study the optical transmittance range for the grown crystals. The powder second harmonic generation test confirms the nonlinear optical property of the grown crystals. From the microhardness test, the hardness of the grown crystals is estimated. The dielectric behaviour, such as the dielectric constant and the loss of the sample, are measured as a function of temperature and frequency. The ac conductivity of the grown crystals is also studied and the activation energy is calculated. (paper)

  18. Estimation of free energy barriers in the cytoplasmic and mitochondrial aspartate aminotransferase reactions probed by hydrogen-exchange kinetics of C alpha-labeled amino acids with solvent

    Energy Technology Data Exchange (ETDEWEB)

    Julin, D.A.; Wiesinger, H.; Toney, M.D.; Kirsch, J.F. (Univ. of California, Berkeley (USA))

    1989-05-02

    The existence of the postulated quinonoid intermediate in the cytoplasmic aspartate amino-transferase catalyzed transamination of aspartate to oxaloacetate was probed by determining the extent of transfer of tritium from the C alpha position of tritiated L-aspartate to pyridoxamine 5'-phosphate in single turnover experiments in which washout from the back-reaction was obviated by product trapping. The maximum amount of transferred tritium observed was 0.7%, consistent either with a mechanism in which a fraction of the net transamination reaction proceeds through a quinonoid intermediate or with a mechanism in which this intermediate is formed off the main reaction pathway. It is shown that transfer of labeled hydrogen from the amino acid to cofactor cannot be used to differentiate a stepwise from a concerted transamination mechanism. The amount of tritium transferred is a function of the rate constant for torsional equilibration about the epsilon-amino group of Lys-258, the presumptive abstractor of the C alpha proton; the relative rate constants for hydrogen exchange with solvent versus cofactor protonation; and the tritium isotope effect on this ratio. The free energy barriers facing the covalent intermediate between aldimine and keto acid product (i.e., ketimine and possibly quinonoid) were evaluated relatively by comparing the rates of C alpha-hydrogen exchange in starting amino acid with the rates of keto acid formation. The value of theta (= kexge/kprod) was found to be 2.6 for the reaction of cytoplasmic isozyme with aspartate and ca. 0.5 for that of the mitochondrial form with glutamate.

  19. Glutamate Racemase Is the Primary Target of β-Chloro-d-Alanine in Mycobacterium tuberculosis

    Science.gov (United States)

    Rodenburg, Anne; Khoury, Hania; de Chiara, Cesira; Howell, Steve; Snijders, Ambrosius P.

    2016-01-01

    The increasing global prevalence of drug resistance among many leading human pathogens necessitates both the development of antibiotics with novel mechanisms of action and a better understanding of the physiological activities of preexisting clinically effective drugs. Inhibition of peptidoglycan (PG) biosynthesis and cross-linking has traditionally enjoyed immense success as an antibiotic target in multiple bacterial pathogens, except in Mycobacterium tuberculosis, where it has so far been underexploited. d-Cycloserine, a clinically approved antituberculosis therapeutic, inhibits enzymes within the d-alanine subbranch of the PG-biosynthetic pathway and has been a focus in our laboratory for understanding peptidoglycan biosynthesis inhibition and for drug development in studies of M. tuberculosis. During our studies on alternative inhibitors of the d-alanine pathway, we discovered that the canonical alanine racemase (Alr) inhibitor β-chloro–d-alanine (BCDA) is a very poor inhibitor of recombinant M. tuberculosis Alr, despite having potent antituberculosis activity. Through a combination of enzymology, microbiology, metabolomics, and proteomics, we show here that BCDA does not inhibit the d-alanine pathway in intact cells, consistent with its poor in vitro activity, and that it is instead a mechanism-based inactivator of glutamate racemase (MurI), an upstream enzyme in the same early stage of PG biosynthesis. This is the first report to our knowledge of inhibition of MurI in M. tuberculosis and thus provides a valuable tool for studying this essential and enigmatic enzyme and a starting point for future MurI-targeted antibacterial development. PMID:27480853

  20. Persistent GABAA/C responses to gabazine, taurine and beta-alanine in rat hypoglossal motoneurons.

    Science.gov (United States)

    Chesnoy-Marchais, D

    2016-08-25

    In hypoglossal motoneurons, a sustained anionic current, sensitive to a blocker of ρ-containing GABA receptors, (1,2,5,6-tetrahydropyridin-4-yl)methylphosphinic acid (TPMPA) and insensitive to bicuculline, was previously shown to be activated by gabazine. In order to better characterize the receptors involved, the sensitivity of this atypical response to pentobarbital (30μM), allopregnanolone (0.3μM) and midazolam (0.5μM) was first investigated. Pentobarbital potentiated the response, whereas the steroid and the benzodiazepine were ineffective. The results indicate the involvement of hybrid heteromeric receptors, including at least a GABA receptor ρ subunit and a γ subunit, accounting for the pentobarbital-sensitivity. The effects of the endogenous β amino acids, taurine and β-alanine, which are released under various pathological conditions and show neuroprotective properties, were then studied. In the presence of the glycine receptor blocker strychnine (1μM), both taurine (0.3-1mM) and β-alanine (0.3mM) activated sustained anionic currents, which were partly blocked by TPMPA (100μM). Thus, both β amino acids activated ρ-containing GABA receptors in hypoglossal motoneurons. Bicuculline (20μM) reduced responses to taurine and β-alanine, but small sustained responses persisted in the presence of both strychnine and bicuculline. Responses to β-alanine were slightly increased by allopregnanolone, indicating a contribution of the bicuculline- and neurosteroid-sensitive GABAA receptors underlying tonic inhibition in these motoneurons. Since sustained activation of anionic channels inhibits most mature principal neurons, the ρ-containing GABA receptors permanently activated by taurine and β-alanine might contribute to some of their neuroprotective properties under damaging overexcitatory situations. PMID:27246441

  1. Splice-mediated insertion of an Alu sequence inactivates ornithine δ-aminotransferase: A role for Alu elements in human mutation

    International Nuclear Information System (INIS)

    In studies of mutations causing deficiency of ornithine δ-aminotransferase the authors found an allele whose mature mRNA has a 142-nucleotide insertion at the junction of sequences from exons 3 and 4. The insert derives from an Alu element in ornithine δ-aminotransferase intron 3 oriented in the direction opposite to transcription (an antisense Alu). A guanine → cytosine transversion creates a donor splice site in this Alu, activating a cryptic acceptor splice site at its 5' end and causing splice-mediated insertion of an Alu fragment into the mature ornithine-δ-aminotransferase mRNA. The authors note that the complement of the Alu consensus sequence has at least two cryptic acceptor sites and several potential donor sequences and predict that similar mutations will be found in other genes

  2. Enhancement of solubility in Escherichia coli and purification of an aminotransferase from Sphingopyxis sp. MTA144 for deamination of hydrolyzed fumonisin B1

    Directory of Open Access Journals (Sweden)

    Hartinger Doris

    2010-08-01

    Full Text Available Abstract Background Fumonisin B1 is a cancerogenic mycotoxin produced by Fusarium verticillioides and other fungi. Sphingopyxis sp. MTA144 can degrade fumonisin B1, and a key enzyme in the catabolic pathway is an aminotransferase which removes the C2-amino group from hydrolyzed fumonisin B1. In order to study this aminotransferase with respect to a possible future application in enzymatic fumonisin detoxification, we attempted expression of the corresponding fumI gene in E. coli and purification of the enzyme. Since the aminotransferase initially accumulated in inclusion bodies, we compared the effects of induction level, host strain, expression temperature, solubility enhancers and a fusion partner on enzyme solubility and activity. Results When expressed from a T7 promoter at 30°C, the aminotransferase accumulated invariably in inclusion bodies in DE3 lysogens of the E. coli strains BL21, HMS174, Rosetta 2, Origami 2, or Rosetta-gami. Omission of the isopropyl-beta-D-thiogalactopyranoside (IPTG used for induction caused a reduction of expression level, but no enhancement of solubility. Likewise, protein production but not solubility correlated with the IPTG concentration in E. coli Tuner(DE3. Addition of the solubility enhancers betaine and sorbitol or the co-enzyme pyridoxal phosphate showed no effect. Maltose-binding protein, used as an N-terminal fusion partner, promoted solubility at 30°C or less, but not at 37°C. Low enzyme activity and subsequent aggregation in the course of purification and cleavage indicated that the soluble fusion protein contained incorrectly folded aminotransferase. Expression in E. coli ArcticExpress(DE3, which co-expresses two cold-adapted chaperonins, at 11°C finally resulted in production of appreciable amounts of active enzyme. Since His tag-mediated affinity purification from this strain was hindered by co-elution of chaperonin, two steps of chromatography with optimized imidazole concentration in the

  3. The alanine detector in BNCT dosimetry: Dose response in thermal and epithermal neutron fields

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, T., E-mail: schmito@uni-mainz.de [Institute for nuclear chemistry, Johannes Gutenberg-University, Mainz D-55128 (Germany); Bassler, N. [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, Aarhus 8000 (Denmark); Blaickner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220 (Austria); Ziegner, M. [AIT Austrian Institute of Technology GmbH, Vienna A-1220, Austria and TU Wien, Vienna University of Technology, Vienna A-1020 (Austria); Hsiao, M. C. [Insitute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Liu, Y. H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Koivunoro, H. [Department of Physics, University of Helsinki, POB 64, FI-00014, Finland and HUS Medical Imaging Center, Helsinki University Central Hospital, FI-00029 HUS (Finland); Auterinen, I.; Serén, T.; Kotiluoto, P. [VTT Technical Research Centre of Finland, Espoo (Finland); Palmans, H. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW, United Kingdom and Medical Physics Group, EBG MedAustron GmbH, Wiener Neustadt A-2700 (Austria); Sharpe, P. [National Physical Laboratory, Acoustics and Ionising Radiation Division, Teddington TW11 0LW (United Kingdom); Langguth, P. [Department of Pharmacy and Toxicology, University of Mainz, Mainz D-55128 (Germany); Hampel, G. [Institut für Kernchemie, Johannes Gutenberg-Universität, Mainz D-55128 (Germany)

    2015-01-15

    Purpose: The response of alanine solid state dosimeters to ionizing radiation strongly depends on particle type and energy. Due to nuclear interactions, neutron fields usually also consist of secondary particles such as photons and protons of diverse energies. Various experiments have been carried out in three different neutron beams to explore the alanine dose response behavior and to validate model predictions. Additionally, application in medical neutron fields for boron neutron capture therapy is discussed. Methods: Alanine detectors have been irradiated in the thermal neutron field of the research reactor TRIGA Mainz, Germany, in five experimental conditions, generating different secondary particle spectra. Further irradiations have been made in the epithermal neutron beams at the research reactors FiR 1 in Helsinki, Finland, and Tsing Hua open pool reactor in HsinChu, Taiwan ROC. Readout has been performed with electron spin resonance spectrometry with reference to an absorbed dose standard in a {sup 60}Co gamma ray beam. Absorbed doses and dose components have been calculated using the Monte Carlo codes FLUKA and MCNP. The relative effectiveness (RE), linking absorbed dose and detector response, has been calculated using the Hansen and Olsen alanine response model. Results: The measured dose response of the alanine detector in the different experiments has been evaluated and compared to model predictions. Therefore, a relative effectiveness has been calculated for each dose component, accounting for its dependence on particle type and energy. Agreement within 5% between model and measurement has been achieved for most irradiated detectors. Significant differences have been observed in response behavior between thermal and epithermal neutron fields, especially regarding dose composition and depth dose curves. The calculated dose components could be verified with the experimental results in the different primary and secondary particle fields. Conclusions: The

  4. Mutation in a D-alanine-D-alanine ligase of Azospirillum brasilense Cd results in an overproduction of exopolysaccharides and a decreased tolerance to saline stress.

    Science.gov (United States)

    Jofré, Edgardo; Fischer, Sonia; Príncipe, Analía; Castro, Marina; Ferrari, Walter; Lagares, Antonio; Mori, Gladys

    2009-01-01

    Bacteria of the genus Azospirillum are free-living nitrogen-fixing, rhizobacteria that are found in close association with plant roots, where they exert beneficial effects on plant growth and yield in many crops of agronomic importance. Unlike other bacteria, little is known about the genetics and biochemistry of exopolysaccharides in Azospirillum brasilense. In an attempt to characterize genes associated with exopolysaccharides production, we generated an A. brasilense Cd Tn5 mutant that showed exopolysaccharides overproduction, decreased tolerance to saline conditions, altered cell morphology, and increased sensitivity to detergents. Genetic characterization showed that the Tn5 was inserted within a ddlB gene encoding for a d-alanine-d-alanine ligase, and located upstream of the ftsQAZ gene cluster responsible for cell division in different bacteria. Heterologous complementation of the ddlB Tn5 mutant restored the exopolysaccharides production to wild-type levels and the ability to grow in the presence of detergents, but not the morphology and growth characteristics of the wild-type bacteria, suggesting a polar effect of Tn5 on the fts genes. This result and the construction of a nonpolar ddlB mutant provide solid evidence of the presence of transcriptional coupling between a gene associated with peptidoglycan biosynthesis and the fts genes required to control cell division.

  5. Purification, characterization and gene cloning of thermostable O-acetyl-L-serine sulfhydrylase forming β-cyano-L-alanine

    International Nuclear Information System (INIS)

    A thermophilic and cyanide ion-tolerant bacterium, Bacillus stearothermophilus CN3 isolated from a hot spring in Japan, was found to produce thermostable β-cyano-L-alanine synthase. The enzyme catalyzes the synthesis of β-cyano-L-alanine from O-acetyl-L-serine and cyanide ions. The purified enzyme has a molecular mass of approximately 70 kDa and consists of two identical sub-units. It was stable in the pH range of 6.0 to 10.0 and up to 70degC. The enzyme also catalyzes the synthesis of various β-substituted-L-alanine derivatives from O-acetyl-L-serine and nucleophilic reagents. The gene encoding the β-cyano-L-alanine synthase was isolated from B. stearothermophilus CN3. Sequence homology analysis revealed that the β-cyano-L-alanine synthase of the bacterium is O-acetyl-L-serine sulfhydrylase. A recombinant plasmid, constructed by ligation of the cloned gene and an expression vector, pKK223-3, was introduced into E. coli JM109. The transformed E. coli cells overexpressed β-cyano-L-alanine synthase. Heat stable β-cyano-L-alanine synthase can be applied to the synthesis of [4-11C]L-2,4-diaminobutyric acid as a tracer for positron emission tomography. (author)

  6. New classes of alanine racemase inhibitors identified by high-throughput screening show antimicrobial activity against Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Karen G Anthony

    Full Text Available BACKGROUND: In an effort to discover new drugs to treat tuberculosis (TB we chose alanine racemase as the target of our drug discovery efforts. In Mycobacterium tuberculosis, the causative agent of TB, alanine racemase plays an essential role in cell wall synthesis as it racemizes L-alanine into D-alanine, a key building block in the biosynthesis of peptidoglycan. Good antimicrobial effects have been achieved by inhibition of this enzyme with suicide substrates, but the clinical utility of this class of inhibitors is limited due to their lack of target specificity and toxicity. Therefore, inhibitors that are not substrate analogs and that act through different mechanisms of enzyme inhibition are necessary for therapeutic development for this drug target. METHODOLOGY/PRINCIPAL FINDINGS: To obtain non-substrate alanine racemase inhibitors, we developed a high-throughput screening platform and screened 53,000 small molecule compounds for enzyme-specific inhibitors. We examined the 'hits' for structural novelty, antimicrobial activity against M. tuberculosis, general cellular cytotoxicity, and mechanism of enzyme inhibition. We identified seventeen novel non-substrate alanine racemase inhibitors that are structurally different than any currently known enzyme inhibitors. Seven of these are active against M. tuberculosis and minimally cytotoxic against mammalian cells. CONCLUSIONS/SIGNIFICANCE: This study highlights the feasibility of obtaining novel alanine racemase inhibitor lead compounds by high-throughput screening for development of new anti-TB agents.

  7. Crystallization and preliminary X-ray study of alkaline alanine racemase from Bacillus pseudofirmus OF4

    International Nuclear Information System (INIS)

    An alkaline alanine racemase from alkaliphilic B. pseudofirmus OF4 was expressed in E. coli and purified. Crystallization and preliminarily X-ray crystallographic analysis were performed for the recombinant enzyme. Alanine racemase (DadXOF4), a dimeric endogenous PLP-dependent alkaline enzyme from alkaliphilic Bacillus pseudofirmus OF4, was expressed in Escherichia coli and purified with a His6 tag in a form suitable for X-ray crystallographic analysis. Crystals were grown by the hanging-drop vapour-diffusion method at 291 K using a solution containing 1.4 M sodium/potassium phosphate pH 8.2. The protein crystallized in space group P212121, with two protein molecules in the asymmetric unit

  8. Dosimetry auditing procedure with alanine dosimeters for light ion beam therapy

    DEFF Research Database (Denmark)

    Ableitinger, Alexander; Vatnitsky, Stanislav; Herrmann, Rochus;

    2013-01-01

    of the biological dose is out of scope of the current work. Materials and methods The audit procedure was based on a homogeneous phantom that mimics the dimension of a head (20 × 20 × 21 cm3). The phantom can be loaded either with an ionisation chamber or 20 alanine dosimeters plus 2 radiochromic EBT films. Dose......Background and purpose In the next few years the number of facilities providing ion beam therapy with scanning beams will increase. An auditing process based on an end-to-end test (including CT imaging, planning and dose delivery) could help new ion therapy centres to validate their entire logistic...... of about 3%. Conclusions Alanine dosimeters are suitable detectors for dosimetry audits in ion beam therapy and the presented end-to-end test is feasible. If further studies show similar results, this dosimetric audit could be implemented as a credentialing procedure for clinical proton and carbon beam...

  9. Chiral effects on helicity studied via the energy landscape of short (D, L)-alanine peptides.

    Science.gov (United States)

    Neelamraju, Sridhar; Oakley, Mark T; Johnston, Roy L

    2015-10-28

    The homochirality of natural amino acids facilitates the formation of regular secondary structures such as α-helices and β-sheets. Here, we study the relationship between chirality and backbone structure for the example of hexa-alanine. The most stable stereoisomers are identified through global optimisation. Further, the energy landscape, a database of connected low-energy local minima and transition points, is constructed for various neutral and zwitterionic stereoisomers of hexa-alanine. Three order parameters for partial helicity are applied and metric disconnectivity graphs are presented with partial helicity as a metric. We also apply the Zimm-Bragg model to derive average partial helicities for Ace-(L-Ala)6-NHMe, Ace-(D-Ala-L-Ala)3-NHMe, and Ace-(L-Ala)3-(D-Ala)3-NHMe from the database of local minima and compare with previous studies.

  10. Membrane topology of the electrogenic aspartate-alanine antiporter AspT of Tetragenococcus halophilus.

    Science.gov (United States)

    Nanatani, Kei; Ohonishi, Fumito; Yoneyama, Hiroshi; Nakajima, Tasuku; Abe, Keietsu

    2005-03-01

    AspT is an electrogenic aspartate:alanine exchange protein that represents the vectorial component of a proton-motive metabolic cycle found in some strains of Tetragenococcus halophilus. AspT is the sole member of a new family, the Aspartate: Alanine Exchanger (AAE) family, in secondary transporters, according to the computational classification proposed by Saier et al. (http://www.biology.ucsd.edu/~msaier/transport/). We analyzed the topology of AspT biochemically, by using fusion methods in combination with alkaline phosphatase or beta-lactamase. These results suggested that AspT has a unique topology; 8 TMS, a large cytoplasmic loop (183 amino acids) between TMS5 and TMS6, and N- and C-termini that both face the periplasm. These results demonstrated a unique 2D-structure of AspT as the novel AAE family. PMID:15670744

  11. Crystallization and preliminary X-ray diffraction analysis of alanine racemase from Pseudomonas putida YZ-26

    International Nuclear Information System (INIS)

    A recombinant alanine racemase from the Pseudomonas putida YZ-26, has been crystallized by the sitting-drop vapor-diffusion method and X-ray diffraction data were collected to 2.4 Å. A recombinant form of alanine racemase (Alr) from Pseudomonas putida YZ-26 has been crystallized by the sitting-drop vapour diffusion method. X-ray diffraction data were collected to 2.4 Å resolution. The crystals belong to the space group C2221, with unit-cell parameters a = 118.08, b = 141.86, c = 113.83 Å, and contain an Alr dimer in the asymmetric unit. The Matthews coefficient and the solvent content were calculated to be 2.8 Å3 Da−1 and approximately 50%, respectively

  12. A reference dosimetric system for dose interval of radiotherapy based on alanine/RPE

    International Nuclear Information System (INIS)

    This work describes the development of a reference dosimetric system based on alanine/EPR for radiotherapy dose levels. Currently the IPEN is concluding a similar system for the dose range used for irradiation of products, 10-105 Gy. The objective of this work is to present the efforts towards to improve the measure accuracy for doses in the range between 1-10 Gy. This system could be used as reference by radiotherapy services, as much in the quality control of the equipment, as for routine accompaniment of more complex handling where the total doses can reach some grays. The system uses alanine as detector and electronic paramagnetic resonance - EPR as measure technique. To reach accuracy better than 5% mathematical studies on the best optimization of the EPR spectrometer parameters and methods for the handling of the EPR sign are discussed. (author)

  13. Chiral effects on helicity studied via the energy landscape of short (d, l)-alanine peptides

    Science.gov (United States)

    Neelamraju, Sridhar; Oakley, Mark T.; Johnston, Roy L.

    2015-10-01

    The homochirality of natural amino acids facilitates the formation of regular secondary structures such as α-helices and β-sheets. Here, we study the relationship between chirality and backbone structure for the example of hexa-alanine. The most stable stereoisomers are identified through global optimisation. Further, the energy landscape, a database of connected low-energy local minima and transition points, is constructed for various neutral and zwitterionic stereoisomers of hexa-alanine. Three order parameters for partial helicity are applied and metric disconnectivity graphs are presented with partial helicity as a metric. We also apply the Zimm-Bragg model to derive average partial helicities for Ace-(l-Ala)6-NHMe, Ace-(d-Ala-l-Ala)3-NHMe, and Ace-(l-Ala)3-(d-Ala)3-NHMe from the database of local minima and compare with previous studies.

  14. The local atomic structure of di-alanine amino acid derivative of protoporphyrin IX

    International Nuclear Information System (INIS)

    The photophysical and photochemical properties of photosensitizers bearing potential for photodynamic diagnosis (PDD) and treatment (PDT) of malignant tissues strictly depend on the details of their chemical processing. In this work, the x-ray absorption spectroscopy (XAFS) and electron spin resonance (ESR) techniques were applied to determine the nearest neighbourhood of iron in the di-alanine amino acid derivative of protoporphyrin IX (L-alanine diprotoporphyrinate). The investigated compound is a technological precursor for novel-class, highly water-soluble protoporphyrin IX-based photosensitizers, which have potential for applications in PDD and PDT and have just entered phase I clinical trials. Knowing the chemical content and exact atomic structures of the technological precursor, as well as of the high-purity final product, which all might contain some contamination, is a prerequisite for preparing photosensitizers for preliminary clinical tests

  15. Orientation of crystals in alanine dosimeter assessed by DRS, as seen in EPR spectra evaluation

    International Nuclear Information System (INIS)

    The alanine dosimeter made for evaluation by diffuse light reflection spectrophotometry (ALA/DRS) does not show the effect of orientation of crystals. Supposed deviation from random orientation has been investigated by EPR spectroscopy. EPR investigation shows that in spite of the very fine size of L-alanine crystals, they are oriented in thin layers of the polyethylene matrix. Specially prepared films with deliberately well oriented crystals have confirmed this observation. Our ALA/DRS dosimeter can be evaluated by the EPR method for the concentration of free radicals, providing that the dominating crystal orientation in the dosimetric film is indicated on it as an arrow, and the sample is inserted into the magnetic cavity always in the same orientation as has been done during the calibration operation. (author). 6 refs., 2 figs

  16. A polymer-alanine film for measurements of radiation dose distributions

    International Nuclear Information System (INIS)

    A film dosimeter (0.35 mm thick) composed of polyethylene-vinyl acetate and microcrystalline L-α-alanine has been prepared and investigated with respect to dosimetric properties using electron spin resonance spectroscopy. The useful absorbed dose range is ∼ 25 to 105 Gy and no dose-rate dependence of the response is observed between 1 and 107 Gy s-1 within the dose range up to 50 kGy. With irradiation temperature increasing from 25 to 800C, the response increases at most by 10%. The response is stable, within experimental uncertainty, at least up to 2500 h after irradiation. The suitability of the polymer-alanine film for measurements of ionizing photon and electron dose distributions is demonstrated. (author)

  17. Multi-coincidence measurements in gas-phase amino acid alanine after valence level ionization

    International Nuclear Information System (INIS)

    Full text: The first chiral amino acids having distinct enantiomeric structures is the alanine. Therefore the study of such molecules is important for developing our understanding of this class of molecule. In this work, we report coincidence measurements between photoelectron and photoion, and total ion yield (TIY) measurements after valence level ionization of D,L-alanine in gas phase. The experiments were performed at the Brazilian Synchrotron Light Source (LNLS) at the Toroidal Grating Monochromator beamline (D0-5A TGM) in the 12-35 eV energy range. The end-station of the beamline is composed by a time-of-flight (TOF) spectrometer specially build for the photoelectron-photoion-photoion (PEPIPICO) measurements. The TIY have been compared with valence photoelectron spectra recorded with synchrotron radiation reported in the literature and have been discussed in a comparative form. The results will be presented during the conference

  18. Radiation-induced reactions in D, L-α-alanine adsorbed in solid surfaces

    International Nuclear Information System (INIS)

    The aim of this work is to study the behavior under irradiation of D, L and D-L α-alanine adsorbed in solid surfaces, as possible phase in the chemical evolution that may have occurred on the primitive Earth or in extraterrestrial environments and to evaluate the contribution of solids (a clay mineral) as shields for the adsorbed amino acids against a external energy source. The results show that α-alanine is adsorbed in the surfaces as function of pH and its yield of decomposition in mineral suspension is lower than the system without the solid surface. These results show the importance of nuclear techniques in these types of studies. (author)

  19. The behaviour of alanine dosimeters at temperatures between 100 and 300 K

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, P.H.G. [National Physical Laboratory, Teddington TW11 0LW (United Kingdom)], E-mail: peter.sharpe@npl.co.uk; Sephton, J.P.; Gouldstone, C.A. [National Physical Laboratory, Teddington TW11 0LW (United Kingdom)

    2009-07-15

    A cryostat has been constructed to enable irradiations in a MDS Nordion Gammacell 220 irradiator to be carried out at selected temperatures between 100 and 300 K. The principle of operation and the performance of this cryostat are described and results are given of a study into the behaviour of alanine dosimeters at cryogenic temperatures. This work extends previously published data to the region between solid CO{sub 2} and liquid N{sub 2} temperatures and has demonstrated complex dose-dependent behaviour. A sharp discontinuity in the effect of temperature on alanine dosimeter response has been found in the region between 150 and 180 K, with no further influence of irradiation temperature on response observed below this point.

  20. The behaviour of alanine dosimeters at temperatures between 100 and 300 K

    Science.gov (United States)

    Sharpe, P. H. G.; Sephton, J. P.; Gouldstone, C. A.

    2009-07-01

    A cryostat has been constructed to enable irradiations in a MDS Nordion Gammacell 220 irradiator to be carried out at selected temperatures between 100 and 300 K. The principle of operation and the performance of this cryostat are described and results are given of a study into the behaviour of alanine dosimeters at cryogenic temperatures. This work extends previously published data to the region between solid CO 2 and liquid N 2 temperatures and has demonstrated complex dose-dependent behaviour. A sharp discontinuity in the effect of temperature on alanine dosimeter response has been found in the region between 150 and 180 K, with no further influence of irradiation temperature on response observed below this point.

  1. Development of DL-alanine systems for gamma radiation and electron dosimetry

    International Nuclear Information System (INIS)

    Two different dosimetric systems using DL-Alanine samples were employed to determine the absorbed dose from 60Co gamma-rays source and electrons emitted from an accelerator. The first dosimetric system is based on the relationship between free radicals produced and the absorbed dose using the electron spin resonance (ESR) technique. Details on the sample preparation, the spectrometer parameter setting, the analysis of the ESR signal to dose, the influence of dose rate and the radiation type dependence are described. The second dosimetric system is based on the determination by absorbance spectrophotometry of the complex produced, which are formed when the irradiated alanine is dissolved in a solution containing ferrous ammonium sulphate xylenol in 0,05 N H2 SO4 . Different concentrations for each reagents has been analyzed in the preparation of this solution as well as the influence caused by radiation type and dose rate in the absorbance. (author)

  2. Role of alanine-valine transaminase in Salmonella typhimurium and analysis of an avtA::Tn5 mutant.

    OpenAIRE

    Berg, C M; Whalen, W A; Archambault, L B

    1983-01-01

    In Salmonella typhimurium, as in Escherichia coli, mutations in avtA, the gene encoding the alanine-valine transaminase (transaminase C), are silent unless they are combined with mutations involved in isoleucine-valine biosynthesis. avtA is repressed by leucine or alanine but not by valine. Transaminase C is found at reduced levels upon starvation for any one of several amino acids. We hypothesize that this is due to repression of avtA by the elevated alanine and leucine pools found in amino ...

  3. L-{alpha} alanine crystals: theoretical and experimental morphology and habit modifications in CaCO{sub 3} solution

    Energy Technology Data Exchange (ETDEWEB)

    Massimino, F.; Bruno, M.; Rubbo, M.; Aquilano, D. [Dipartimento di Scienze Mineralogiche e Petrologiche, Universita di Torino, via Valperga Caluso 35, 10125 Torino (Italy)

    2011-08-15

    Empirical potential has been modified for {alpha}-alanine intermolecular interaction, in order to perform a Periodic Bond Chain (PBC) analysis. Equilibrium and growth shapes have been predicted in vacuum and the equilibrium shape has been successfully modified by the solvent interaction. {alpha}-alanine crystals have been prepared both in pure and in CaCO{sub 3} aqueous solution. Then, habit modification was observed and surface morphology analysis has been carried out on metallized crystals. Epitaxial model acting at the {alpha}-alanine/ CaCO{sub 3} interfaces is also proposed. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  4. Sequential enzymatic synthesis and separation of 13N-L-glutamic acid and 13N-L-alanine

    International Nuclear Information System (INIS)

    The sequential enzymatic synthesis and separation of 13N-L-glutamic acid and 13N-L-alanine are described. Basically, that involves the synthesis of 13N-L-glutamic acid by one enzyme, the transamination of the labeled glutamic acid to form 13N-L-alanine by a second enzyme, and the separation of the two amino acids by rapid column chromatography. The 13N-L-alanine was evaluated in animals by imaging and tissue distribution studies and showed good potential as a pancreatic imaging agent

  5. Electronic structure and first hyperpolarizability of poly(2-L-alanine-3-sodium nitrate (I)) crystals

    Indian Academy of Sciences (India)

    A Duarte Moller

    2014-10-01

    Poly(2-L-alanine-3-sodium nitrate (I)), -LASN, crystals have been grown by slow evaporation at room temperature. The nominal size of the crystals obtained by the method was of 500 nm. The UV–Vis spectrum shows a wide range, where absorption is lacking around 532 nm, which is required in order to have the second harmonic emission, when an incident radiation of 1064 nm strikes on the crystal. This guarantees the possible use of the crystal in visible light applications. The transparent nature of the crystal in the visible and infrared regions within the transmission spectrum confirms the nonlinear optical properties of the crystal. Additionally, Fourier transform infrared spectroscopy displays its functional groups which correspond to the poly(2-L-alanine-3-sodium nitrate (I)), where the presence of nitrates in the lattice generally can be identified by their characteristic signature within the 1660–1625, 1300–1255, 870–833 and 763–690 cm-1 range. Single crystal diffraction was carried out in order to determine atomic structure and lattice parameter. Structural parameters were = 5.388(9) Å, = 9.315(15) Å and = 13.63(2) Å. The structure of poly(2-Lalanine-3-sodium nitrate (I)) shown by single crystal diffraction shows an asymmetric unit consisting of one sodium and one nitrate ion and one L-alanine molecule. The coordination geometry around the sodium atom was trigonal bipyramidal, with three bidentate nitrate anions coordinating through their oxygen atoms and two L-alanine molecules, each coordinating through one carboxyl oxygen atom. Electronic structure was obtained by using the Becke–Lee–Yang–Part and Hartree–Fock approximations with hybrid exchangecorrelation three-parameter functional and G-311**G() basis set. Theoretical and experimental results were compared and discussed as having an excellent agreement among them.

  6. β-Alanine supplementation enhances human skeletal muscle relaxation speed but not force production capacity.

    OpenAIRE

    Hannah, R; Stannard, R. L.; Minshull, C; Artioli, G. G.; Harris, R. C.; Sale, C.

    2015-01-01

    β-Alanine (BA) supplementation improves human exercise performance. One possible explanation for this is an enhancement of muscle contractile properties, occurring via elevated intramuscular carnosine resulting in improved calcium sensitivity and handling. This study investigated the effect of BA supplementation on in vivo contractile properties and voluntary neuromuscular performance. Twenty-three men completed two experimental sessions, pre- and post-28 days supplementation with 6.4 g/day o...

  7. Cyanobacterial Neurotoxin β-N-Methylamino-L-alanine (BMAA) in Shark Fins

    OpenAIRE

    John Pablo; Mash, Deborah C.; Banack, Sandra A; Neil Hammerschlag; Margaret Basile; Kiyo Mondo

    2012-01-01

    Sharks are among the most threatened groups of marine species. Populations are declining globally to support the growing demand for shark fin soup. Sharks are known to bioaccumulate toxins that may pose health risks to consumers of shark products. The feeding habits of sharks are varied, including fish, mammals, crustaceans and plankton. The cyanobacterial neurotoxin β-N-methylamino-L-alanine (BMAA) has been detected in species of free-living marine cyanobacteria and may bioaccumulate in the ...

  8. β-alanine supplementation improves isometric endurance of the knee extensor muscles

    Directory of Open Access Journals (Sweden)

    Sale Craig

    2012-06-01

    Full Text Available Abstract Background We examined the effect of four weeks of β-alanine supplementation on isometric endurance of the knee extensors at 45% maximal voluntary isometric contraction (MVIC. Methods Thirteen males (age 23 ± 6 y; height 1.80 ± 0.05 m; body mass 81.0 ± 10.5 kg, matched for pre-supplementation isometric endurance, were allocated to either a placebo (n = 6 or β-alanine (n = 7; 6.4 g·d-1 over 4 weeks supplementation group. Participants completed an isometric knee extension test (IKET to fatigue, at an intensity of 45% MVIC, before and after supplementation. In addition, two habituation tests were completed in the week prior to the pre-supplementation test and a further practice test was completed in the week prior to the post-supplementation test. MVIC force, IKET hold-time, and impulse generated were recorded. Results IKET hold-time increased by 9.7 ± 9.4 s (13.2% and impulse by 3.7 ± 1.3 kN·s-1 (13.9% following β-alanine supplementation. These changes were significantly greater than those in the placebo group (IKET: t(11 = 2.9, p ≤0.05; impulse: t(11 = 3.1, p ≤ 0.05. There were no significant changes in MVIC force in either group. Conclusion Four weeks of β-alanine supplementation at 6.4 g·d-1 improved endurance capacity of the knee extensors at 45% MVIC, which most likely results from improved pH regulation within the muscle cell as a result of elevated muscle carnosine levels.

  9. The ESR/alanine dosimeter - power dependence of the X-band spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Arber, J.M.; Sharpe, P.H.G. (National Physical Lab., Teddington (UK)); Joly, H.A.; Morton, J.R.; Preston, K.F. (National Research Council, Ottawa (Canada). Steacie Inst. for Molecular Sciences)

    1991-01-01

    Satellite lines which accompany the central feature of the X-band ESR spectrum of {alpha}-alanine dosimeters are shown to be due to forbidden ''spin-flip'' transitions associated with methyl protons on nearby molecules. At microwave powers in excess of 1 mW the satellites increase in intensity relative to the central feature, and thus measurements at higher microwave powers must be based on experimentally determined calibration curves at the appropriate power levels. (author).

  10. Peptide conformational preferences in osmolyte solutions: Transfer free energies of deca-alanine

    OpenAIRE

    Kokubo, Hironori; Hu, Char Y.; Pettitt, B. Montgomery

    2011-01-01

    The nature in which the protecting osmolyte trimethylamine-N-oxide (TMAO) and the denaturing osmolyte urea affect protein stability is investigated simulating a deca-alanine peptide model in multiple conformations of the denatured ensemble. Binary solutions of both osmolytes and mixed osmolyte solutions at physiologically-relevant concentrations of 2:1 (urea:TMAO) are studied using standard molecular dynamics simulations and solvation free energy calculations. Component analysis reveals the d...

  11. β-alanine supplementation improves YoYo intermittent recovery test performance

    Directory of Open Access Journals (Sweden)

    Saunders Bryan

    2012-08-01

    Full Text Available Abstract Background β-alanine supplementation has been shown to improve high-intensity exercise performance and capacity. However, the effects on intermittent exercise are less clear, with no effect shown on repeated sprint activity. The aim of this study was to investigate the effects of β-alanine supplementation on YoYo Intermittent Recovery Test Level 2 (YoYo IR2 performance. Methods Seventeen amateur footballers were allocated to either a placebo (PLA; N = 8 or β-alanine (BA; N = 9 supplementation group, and performed the YoYo IR2 on two separate occasions, pre and post 12 weeks of supplementation during a competitive season. Specifically, players were supplemented from early to mid-season (PLA: N = 5; BA: N = 6 or mid- to the end of the season (PLA: N = 3; BA: N = 3. Data were analysed using a two factor ANOVA with Tukey post-hoc analyses. Results Pre supplementation scores were 1185 ± 216 and 1093 ± 148 m for PLA and BA, with no differences between groups (P = 0.41. YoYo performance was significantly improved for BA (+34.3%, P ≤ 0.001 but not PLA (−7.3%, P = 0.24 following supplementation. 2 of 8 (Early – Mid: 2 of 5; Mid – End: 0 of 3 players improved their YoYo scores in PLA (Range: -37.5 to + 14.7% and 8 of 9 (Early – Mid: 6 of 6; Mid – End: 2 of 3 improved for BA (Range: +0.0 to +72.7%. Conclusions 12 weeks of β-alanine supplementation improved YoYo IR2 performance, likely due to an increased muscle buffering capacity resulting in an attenuation of the reduction in intracellular pH during high-intensity intermittent exercise.

  12. (1S, 3S)-3-amino-4-difluoromethylenyl-1-cyclopentanoic acid (CPP-115), a potent gamma-aminobutyric acid aminotransferase inactivator for the treatment of cocaine addiction

    DEFF Research Database (Denmark)

    Pan, Yue; Gerasimov, Madina R; Kvist, Trine;

    2012-01-01

    Vigabatrin, a GABA aminotransferase (GABA-AT) inactivator, is used to treat infantile spasms and refractory complex partial seizures and is in clinical trials to treat addiction. We evaluated a novel GABA-AT inactivator (CPP-115) and observed that it does not exhibit other GABAergic or off-target...

  13. Lactococcal aminotransferases AraT and BcaT are key enzymes for the formation of aroma compounds from amino acids in cheese

    NARCIS (Netherlands)

    Rijnen, L.; Yvon, M.; Kranenburg, van R.; Courtin, P.; Verheul, A.; Chambellon, E.; Smit, G.

    2003-01-01

    Amino acid catabolism plays a major role in cheese aroma development. Previously, we showed that the lactococcal aminotransferases AraT and BcaT initiate the conversion of aromatic amino acids, branched-chain amino acids and methionine to aroma compounds. In this study, we evaluated the importance o

  14. Dosimetry for small fields in stereotactic radiosurgery using gafchromic MD-V2-55 film, TLD-100 and alanine dosimeters.

    Directory of Open Access Journals (Sweden)

    Guerda Massillon-J L

    Full Text Available This work investigated the suitability of passive dosimeters for reference dosimetry in small fields with acceptable accuracy. Absorbed dose to water rate was determined in nine small radiation fields with diameters between 4 and 35 mm in a Leksell Gamma Knife (LGK and a modified linear accelerator (linac for stereotactic radiosurgery treatments. Measurements were made using Gafchromic film (MD-V2-55, alanine and thermoluminescent (TLD-100 dosimeters and compared with conventional dosimetry systems. Detectors were calibrated in terms of absorbed dose to water in (60Co gamma-ray and 6 MV x-ray reference (10×10 cm(2 fields using an ionization chamber calibrated at a standards laboratory. Absorbed dose to water rate computed with MD-V2-55 was higher than that obtained with the others dosimeters, possibly due to a smaller volume averaging effect. Ratio between the dose-rates determined with each dosimeter and those obtained with the film was evaluated for both treatment modalities. For the LGK, the ratio decreased as the dosimeter size increased and remained constant for collimator diameters larger than 8 mm. The same behaviour was observed for the linac and the ratio increased with field size, independent of the dosimeter used. These behaviours could be explained as an averaging volume effect due to dose gradient and lack of electronic equilibrium. Evaluation of the output factors for the LGK collimators indicated that, even when agreement was observed between Monte Carlo simulation and measurements with different dosimeters, this does not warrant that the absorbed dose to water rate in the field was properly known and thus, investigation of the reference dosimetry should be an important issue. These results indicated that alanine dosimeter provides a high degree of accuracy but cannot be used in fields smaller than 20 mm diameter. Gafchromic film can be considered as a suitable methodology for reference dosimetry. TLD dosimeters are not

  15. Survivability and reactivity of glycine and alanine in early oceans: effects of meteorite impacts.

    Science.gov (United States)

    Umeda, Yuhei; Fukunaga, Nao; Sekine, Toshimori; Furukawa, Yoshihiro; Kakegawa, Takeshi; Kobayashi, Takamichi; Nakazawa, Hiromoto

    2016-01-01

    Prebiotic oceans might have contained abundant amino acids, and were subjected to meteorite impacts, especially during the late heavy bombardment. It is so far unknown how meteorite impacts affected amino acids in the early oceans. Impact experiments were performed under the conditions where glycine was synthesized from carbon, ammonia, and water, using aqueous solutions containing (13)C-labeled glycine and alanine. Selected amino acids and amines in samples were analyzed with liquid chromatography-mass spectrometry (LC/MS). In particular, the (13)C-labeled reaction products were analyzed to distinguish between run products and contaminants. The results revealed that both amino acids survived partially in the early ocean through meteorite impacts, that part of glycine changed into alanine, and that large amounts of methylamine and ethylamine were formed. Fast decarboxylation was confirmed to occur during such impact processes. Furthermore, the formation of n-butylamine, detected only in the samples recovered from the solutions with additional nitrogen and carbon sources of ammonia and benzene, suggests that chemical reactions to form new biomolecules can proceed through marine impacts. Methylamine and ethylamine from glycine and alanine increased considerably in the presence of hematite rather than olivine under similar impact conditions. These results also suggest that amino acids present in early oceans can contribute further to impact-induced reactions, implying that impact energy plays a potential role in the prebiotic formation of various biomolecules, although the reactions are complicated and depend upon the chemical environments as well. PMID:26369758

  16. Chiral molecule for spin filtering purposes: the study of L- and D-Alanine

    Science.gov (United States)

    Yitamben, Esmeralda; Rosenberg, Richard; Guisinger, Nathan

    2011-03-01

    The field of molecular electronics has attracted scientists by the great opportunities and versatility it offers as a replacement for standard semiconductor electronics with organic materials, thus bringing down the cost, and opening endless possibilities for chemical synthesis, and scientific breakthrough. Of particular interest is the use of chiral molecules, such as alanine, for spin filtering studies in hope of creating highly spin-polarized charge carriers for spintronics applications. Preliminary studies of both L- and D-alanine on Cu(111) were conducted using scanning tunneling microscopy and spectroscopy, revealing the formation of a 2-dimensional phase at low coverage, a hexagonal ``flower'' pattern at intermediate coverage, and a chain and ring superstructures at high coverage. A model is proposed to explain the surface chemistry and bonding of the molecules on the metallic surface. Current studies of L- and D-alanine on Fe/W show promises in the intermediate coverage regime. This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  17. Effect of dipeptide of glutamine and alanine on severe traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    YANG De-lin; XU Jun-fa

    2007-01-01

    Objective: To determine the effect of dipeptide of glutamine and alanine on patients with severe traumatic brain injury. Methods: A total of 46 patients (31 males and 15 females, aged 7-68 years, (47±9.6) years on average) with severe traumatic brain injury were randomized into two groups: Group G (n=23) and Group C (n=23). The patients in Group G received nutritional remedy with the dipeptide of glutamine and alanine, whereas the patients in Group C received routine nutritional therapy only. GCS changes, the length of stay in the neurosurgical intensive care unit (NICU), the mortality,the count of lymphocytes, related complications including lung infection and hemorrhage of alimentary tracts, etc, were examined and recorded. Results: The fatality rate and the length of stay in NICU in Group G was lower than these in Group C (P<0.05), but no obvious difference was found in GCS changes of the patients between the two groups (P>0.05). The patients with lung infection and alimentary tract hemorrhage in Group G were less than those in Group C (P<0.05). The count of lymphocytes in Group G was more than that in Group C (P<0.05), but no difference was found in other nutritional data. Conclusions: Dipeptide of glutamine and alanine can increase the resisting stress and anti-infection ability of patients with severe traumatic brain injury, which can also lower the mortality and shorten the NICU stay.

  18. Radiation chemistry in alanine irradiated with γ-rays and ion beams

    International Nuclear Information System (INIS)

    In order to extend the application of alanine dosimetry, the behavior of free radicals in solid α-alanine irradiated with γ-rays and with ion beams was studied by electron spin resonance. Stable neutral radicals are produced through the decomposition of originally generated ion radicals in alanine irradiated at 300 K, while at 77 K the ion radicals are stable, and also do not decompose. The rate of the combination reaction of the neutral radicals and of the ion radicals was studied by measuring the saturation behavior of the radical concentration in γ-radiolysis at 300 and at 77 K. The yield of the neutral radicals was compared between 0.5, 1,2 and 3 MeV H+, 0.5, 1, and 3 MeV He+, 175 MeV Ar8+ and 460 MeV Ar13+ ion irradiations. Dependence of the radical yield on the radiation quality is understood more in terms of the rate of the combination reaction between the ion radicals than with that between the neutral radicals, and has to do with high local dose within the ion tracks. (Author)

  19. Alanine dosimetry using a spectrophotometric ferric-xylenol orange complex readout

    Energy Technology Data Exchange (ETDEWEB)

    Laere, K. van; Buysse, J.; Berkvens, P. (Ghent Rijksuniversiteit (Belgium). Lab. voor Kernfysica)

    1989-01-01

    The spectrophotometric dosimetric method using the indirect oxidation of ferrous ions after dissolution of irradiated DL-and L-alanine has been thoroughly investigated with respect to its composition, read-out procedure and dose-response. Optimal concentration of 0.10 N H{sub 2}SO{sub 4}, 0.2 mM xylenol orange and 0.2 mM Fe{sup 2+} were found, giving an absorption maximum at 547 nm. Standardization of chemical processing procedures allows a reproducibility better than 0.5%. The useful dose range has been extended to 0.03-12 kGy by means of slightly different read-out procedure. The quantitative concept of ''indirect yield'', G{sub id}, was introduced for this procedure as a measure of the indirect oxidation capacity of the radicals. It was found to be G{sub id,0}(Fe{sup 3+}) 7.1 ions/100 eV transferred into the alanine. The spectrophotometric readout combines the highly advantageous use of alanine as a dosemeter with the straightforwardness, accuracy and low costs of the chemical procedure. (author).

  20. Alanine dosimetry using a spectrophotometric ferric-xylenol orange complex readout

    International Nuclear Information System (INIS)

    The spectrophotometric dosimetric method using the indirect oxidation of ferrous ions after dissolution of irradiated DL-and L-alanine has been thoroughly investigated with respect to its composition, read-out procedure and dose-response. Optimal concentration of 0.10 N H2SO4, 0.2 mM xylenol orange and 0.2 mM Fe2+ were found, giving an absorption maximum at 547 nm. Standardization of chemical processing procedures allows a reproducibility better than 0.5%. The useful dose range has been extended to 0.03-12 kGy by means of slightly different read-out procedure. The quantitative concept of ''indirect yield'', Gid, was introduced for this procedure as a measure of the indirect oxidation capacity of the radicals. It was found to be Gid,0(Fe3+) 7.1 ions/100 eV transferred into the alanine. The spectrophotometric readout combines the highly advantageous use of alanine as a dosemeter with the straightforwardness, accuracy and low costs of the chemical procedure. (author)

  1. In vivo dosimetry in electron beam teletherapy using electron paramagnetic resonance in L-alanine

    International Nuclear Information System (INIS)

    The aim of this study was to compare radiation doses measured in vivo with the use of ERP/alanine dosimetry with doses calculated using the Cad Plan R.3.1.2 treatment planning system. The doses were measured in vivo using electron paramagnetic resonance (EPR) in L alanine. The detectors consisted of small polyethylene bags filled with crystalline L-alanine. Clinical research was performed on a group of patients undergoing radical and palliative treatment at the Department of Oncology and Radiotherapy of the Medical University of Gdansk. The planned doses were calculated by the Cad Plan R.3.1.2 radiotherapy treatment planning system. The average difference between the measured doses and those calculated by the treatment planning system was, for all 50 fields, 0.6% with a data scatter of 6.3% (standard deviation of a single measurement). The results of in vivo dosimetry showed apt concordance between the prescribed and the actually delivered doses. The 0.6% average difference may be considered satisfactory in routine radiotherapy treatment. (author)

  2. Radiation chemistry in alanine irradiated with {gamma}-rays and ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Hitoshi; Ichikawa, Tsuneki; Yoshida, Hiroshi [Hokkaido Univ., Sapporo (Japan). Faculty of Engineering

    1997-01-01

    In order to extend the application of alanine dosimetry, the behavior of free radicals in solid {alpha}-alanine irradiated with {gamma}-rays and with ion beams was studied by electron spin resonance. Stable neutral radicals are produced through the decomposition of originally generated ion radicals in alanine irradiated at 300 K, while at 77 K the ion radicals are stable, and also do not decompose. The rate of the combination reaction of the neutral radicals and of the ion radicals was studied by measuring the saturation behavior of the radical concentration in {gamma}-radiolysis at 300 and at 77 K. The yield of the neutral radicals was compared between 0.5, 1,2 and 3 MeV H{sup +}, 0.5, 1, and 3 MeV He{sup +}, 175 MeV Ar{sup 8+} and 460 MeV Ar{sup 13+} ion irradiations. Dependence of the radical yield on the radiation quality is understood more in terms of the rate of the combination reaction between the ion radicals than with that between the neutral radicals, and has to do with high local dose within the ion tracks. (Author).

  3. Bond cleavage reactions in the tripeptide tri-alanine upon free electron capture

    International Nuclear Information System (INIS)

    In the present study we performed dissociative electron attachment (DEA) measurements with the tripeptide tri-alanine, C9H17N3O4, utilizing a crossed electron-molecular beam experiment with high electron energy resolution (about 100 meV). Anion efficiency yields as a function of the incident electron energy are obtained for the most abundant anions up to electron energies of ∼ eV. Quantum chemical calculations are performed to determine the thermochemical thresholds for the anions observed in the measurements. There is no evidence of a molecular anion with lifetime of mass spectrometric timescales. The dehydrogenated closed shell anion (M-H)- is one of the fragment anions observed for which the calculations show that H-loss is energetically possible from carboxyl, as well as amide groups. In contrast to the dipeptide di-alanine and monomer alanine the cleavage of the N-Cα bond in the peptide chain is already possible by attachment of electrons at ∼ 0 eV. (authors)

  4. SERUM ACTIVITIES OF ASPARTATE AMINOTRANSFERASE, CREATINE KINASE AND LACTATE DEHYDROGENASE IN HORSES WITH COLIC ATIVIDADE SÉRICA DAS ENZIMAS ASPARTATO AMINOTRANSFERASE, CREATINA QUINASE E LACTATO DESIDROGENASE EM EQÜINOS COM CÓLICA

    Directory of Open Access Journals (Sweden)

    Aureo Evangelista Santana

    2008-12-01

    Full Text Available Seventy equines distributed in two experimental groups were used, G1 (20 healthy equines, and G2 (50 equines with colic. Blood samples were obtained by jugular vein puncture in ten different moments. The variables aspartate aminotransferase (AST, creatine kinase (CK, and lactate dehydrogenase (LDH were determined by spectrophotometric assay using specific reagents. The average values presented by the animals of the G2 for variables CK, AST, and LDH were higher (P<0.05 than the values presented by the animals of the G1 in all the evaluation moments. The results showed for G2 animals suggest the existence of acute muscle injury. The muscle injuries in equines with colic were attributed to the tissue hypoperfusion, and the muscular damage.

    KEY WORDS: Acute abdomen, horses, muscles enzyme. De setenta eqüinos, distribuídos em dois grupos experimentais – G1 (vinte eqüinos hígidos e G2 (cinqüenta eqüinos com cólica –, colheram-se amostras de sangue em dez diferentes momentos, mediante punção da jugular, para a determinação da atividade sérica das enzimas aspartato aminotransferase (AST, creatina quinase (CK e lactato desidrogenase (LDH. Os valores médios apresentados pelos animais do G2, para as variáveis CK, AST e LDH, foram superiores (P<0,05 aos valores médios apresentados pelos animais do G1 em todos os momentos de avaliação. Os resultados apresentados pelos animais com cólica (G2 sugerem a existência de lesão muscular aguda, porém com tendência a cura, e foram atribuídos a hipoperfusão tecidual e a traumas musculares. A análise seriada das enzimas CK, AST e LDH auxilia tanto no diagnóstico de lesões musculares em eqüinos com cólica como no acompanhamento da evolução do processo de cura.

    PALAVRAS-CHAVES: Abdômen agudo, cavalos, enzimas musculares.

  5. Characterization of lithium formate EPR dosimeters for high dose applications - Comparison with alanine

    International Nuclear Information System (INIS)

    Lithium formate and L-α-alanine (alanine) EPR dosimeters were irradiated to doses from 100 Gy to 100 kGy. The irradiations were mainly performed at a Gammacell irradiator with dose rate of approximately 5.5 kGy h-1. Both the peak-to-peak amplitude of the first derivative EPR spectrum and the area under the EPR absorption spectrum were extracted, and the resulting dose dependence of these EPR signal intensity parameters was analyzed. The dependence of the peak-to-peak width of the central resonance in the first derivative EPR spectrum on the dose was also elucidated. In addition, the dependence on dose rate and irradiation temperature for the two materials were measured. Dosimeters were given doses from 100 Gy to 10 kGy at two different Gammacells with dose rates of 5.5 kGy h-1 and 0.6 kGy h-1, respectively, and the results were compared. Furthermore, the EPR signal intensities for dosimeters irradiated to 1 kGy at temperatures from 11 oC to 40 oC were analyzed. By fitting an 'exponential rise to maximum'-function to the dependence of the area under the EPR absorption spectrum on the dose, saturation doses of 53 kGy and 87 kGy for lithium formate and alanine, respectively, were found. Lower estimates were found when analyzing the dose dependence of the peak-to-peak amplitude. Furthermore, the peak-to-peak width was found to increase for doses above 10 kGy. No dose rate dependence for any of the studied materials was observed and the temperature coefficients at 25 oC (i.e. change in dosimeter signal per oC change in irradiation temperature) were 0.154% K-1 and 0.161% K-1 for lithium formate and alanine, respectively. This work demonstrates that lithium formate EPR dosimeters may be suitable for high dose applications, but their signals saturate at lower doses than alanine. The saturation doses found for both materials may be used in theoretical calculations of the dosimeter response following hadron beam irradiations.

  6. Dosimetry auditing procedure with alanine dosimeters for light ion beam therapy

    International Nuclear Information System (INIS)

    Background and purpose: In the next few years the number of facilities providing ion beam therapy with scanning beams will increase. An auditing process based on an end-to-end test (including CT imaging, planning and dose delivery) could help new ion therapy centres to validate their entire logistic chain of radiation delivery. An end-to-end procedure was designed and tested in both scanned proton and carbon ion beams, which may also serve as a dosimetric credentialing procedure for clinical trials in the future. The developed procedure is focused only on physical dose delivery and the validation of the biological dose is out of scope of the current work. Materials and methods: The audit procedure was based on a homogeneous phantom that mimics the dimension of a head (20 × 20 × 21 cm3). The phantom can be loaded either with an ionisation chamber or 20 alanine dosimeters plus 2 radiochromic EBT films. Dose verification aimed at measuring a dose of 10 Gy homogeneously delivered to a virtual-target volume of 8 × 8 × 12 cm3. In order to interpret the readout of the irradiated alanine dosimeters additional Monte Carlo simulations were performed to calculate the energy dependent detector response of the particle fluence in the alanine detector. A pilot run was performed with protons and carbon ions at the Heidelberg Ion Therapy facility (HIT). Results: The mean difference of the absolute physical dose measured with the alanine dosimeters compared with the expected dose from the treatment planning system was −2.4 ± 0.9% (1σ) for protons and −2.2 ± 1.1% (1σ) for carbon ions. The measurements performed with the ionisation chamber indicate this slight underdosage with a dose difference of −1.7% for protons and −1.0% for carbon ions. The profiles measured by radiochromic films showed an acceptable homogeneity of about 3%. Conclusions: Alanine dosimeters are suitable detectors for dosimetry audits in ion beam therapy and the presented end-to-end test is

  7. Determination of muscle protein synthesis rates in fish using (2)H2O and (2)H NMR analysis of alanine.

    Science.gov (United States)

    Marques, Cátia; Viegas, Filipa; Rito, João; Jones, John; Viegas, Ivan

    2016-09-15

    Following administration of deuterated water ((2)H2O), the fractional synthetic rate (FSR) of a given endogenous protein can be estimated by (2)H-enrichment quantification of its alanine residues. Currently, this is measured by mass spectrometry following a derivatization procedure. Muscle FSR was measured by (1)H/(2)H NMR analysis of alanine from seabass kept for 6 days in 5% (2)H-enriched saltwater, following acid hydrolysis and amino acid isolation by cation-exchange chromatography of muscle tissue. The analysis is simple and robust, and provides precise measurements of excess alanine (2)H-enrichment in the 0.1-0.4% range from 50 mmol of alanine recovered from muscle protein. PMID:27418547

  8. Crystallization and preliminary X-ray study of a thermostable alanine racemase from Thermoanaerobacter tengcongensis MB4

    OpenAIRE

    Dong, Hui; Xu, Shujing; Lu, Xiaoyun; He, Guangzheng; Zhao, Ranran; Chen, Shuai; Fu, Sheng; Ju, Jiansong

    2013-01-01

    A thermostable alanine racemase from T. tengcongensis MB4 was expressed in E. coli and purified. Crystallization and preliminary X-ray crystallographic analysis were performed for the recombinant enzyme.

  9. Painting proteins blue: β-(1-azulenyl)-L-alanine as a probe for studying protein-protein interactions.

    Science.gov (United States)

    Moroz, Yurii S; Binder, Wolfgang; Nygren, Patrik; Caputo, Gregory A; Korendovych, Ivan V

    2013-01-18

    We demonstrated that β-(1-azulenyl)-L-alanine, a fluorescent pseudoisosteric analog of tryptophan, exhibits weak environmental dependence and thus allows for using weak intrinsic quenchers, such as methionines, to monitor protein-protein interactions while not perturbing them.

  10. Alanine Esters of Enterococcal Lipoteichoic Acid Play a Role in Biofilm Formation and Resistance to Antimicrobial Peptides

    OpenAIRE

    Fabretti, Francesca; Theilacker, Christian; Baldassarri, Lucilla; Kaczynski, Zbigniew; Kropec, Andrea; Holst, Otto; Huebner, Johannes

    2006-01-01

    Enterococcus faecalis is among the predominant causes of nosocomial infections. Surface molecules like d-alanine lipoteichoic acid (LTA) perform several functions in gram-positive bacteria, such as maintenance of cationic homeostasis and modulation of autolytic activities. The aim of the present study was to evaluate the effect of d-alanine esters of teichoic acids on biofilm production and adhesion, autolysis, antimicrobial peptide sensitivity, and opsonic killing. A deletion mutant of the d...

  11. Expression profiles of carnosine synthesis–related genes in mice after ingestion of carnosine or ß-alanine

    OpenAIRE

    Miyaji Takayuki; Sato Mikako; Maemura Hirohiko; Takahata Yoshihisa; Morimatsu Fumiki

    2012-01-01

    Abstract Background Carnosine is a dipeptide that improves exercise performance. The carnosine synthesis mechanism through carnosine and ß-alanine ingestion remains unclear. Therefore, we investigated the tissue distribution of carnosine synthase, ATP-grasp domain-containing protein-1 (ATPGD1) mRNA, and ATPGD1 and carnosine specific dipeptidase (CN1) gene expression profiles in mice that were given carnosine or ß-alanine orally. Methods ddY mice (7-week-old) were randomly divided into three g...

  12. Expression profiles of carnosine synthesis–related genes in mice after ingestion of carnosine or ß-alanine

    OpenAIRE

    Miyaji, Takayuki; Sato, Mikako; Maemura, Hirohiko; Takahata, Yoshihisa; Morimatsu, Fumiki

    2012-01-01

    Background Carnosine is a dipeptide that improves exercise performance. The carnosine synthesis mechanism through carnosine and ß-alanine ingestion remains unclear. Therefore, we investigated the tissue distribution of carnosine synthase, ATP-grasp domain-containing protein-1 (ATPGD1) mRNA, and ATPGD1 and carnosine specific dipeptidase (CN1) gene expression profiles in mice that were given carnosine or ß-alanine orally. Methods ddY mice (7-week-old) were randomly divided into three groups (n ...

  13. HCV carriers with normal aminotransferase levels: “normal” does not always mean “healthy”

    Directory of Open Access Journals (Sweden)

    Claudio Puoti

    2013-04-01

    Full Text Available BACKGROUND Approximately 30% of patients with chronic HCV infection show persistently normal ALT levels (PNALT, and another 40% have minimally raised ALT values. Although formerly referred to as “healthy” or “asymptomatic” HCV carriers, it has now become clear that the majority of these patients have some degree of histological liver damage. Controversies still exist regarding the definition of “persistent” ALT normality, the virological and histological features of these subjects, and the natural history and optimal management of chronic hepatitis C (CHC with normal ALT. Most patients with normal ALT have histologically proven liver damage that may be significant (> F2 in up to 20% of patients, and might progress toward more severe degree of liver fibrosis. A significant proportion of patients (≥ 20% experiences periods of increased serum ALT (flare associated with disease progression. AIM OF THE STUDY The introduction of the new combination therapy of PEG-IFN plus ribavirin allowed response rates higher than 50%, with a favourable risk-benefit ratio also in patients with benign or slow progressive disease. Given the efficacy of the new treatments, which soon became the standard of care for CHC, it has been suggested that the issue of whether or not to treat subjects with PNALT should be re-evaluated. ALT levels may have less importance in deciding who should be treated. Many other factors might influence the decision to treat, such as the age of the patient, HCV genotype, liver histology, patient’s motivation, symptoms, extrahepatic manifestations, comorbid illness. The role of non-invasive tools for the assessment of liver fibrosis (transient hepatic elastography remains to be further validated.

  14. ESR response to {gamma}-rays of alanine pellets containing B(OH){sub 3} or Gd{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Brai, M. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy); Gennaro, G. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Marrale, M. [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze, Edificio 18, 90128 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy); E-mail: marrale@difter.unipa.it; Bartolotta, A. [Dipartimento Farmacochimico Tossicologico e Biologico, Universita di Palermo, Via Archirafi 32, 90123 Palermo (Italy); Unita CNISM, Palermo and Gruppo V Sezione INFN, Catania (Italy); D' Oca, M.C. [Dipartimento Farmacochimico Tossicologico e Biologico, Universita di Palermo, Via Archirafi 32, 90123 Palermo (Italy)

    2007-04-15

    ESR response to {gamma}-irradiation (1-50Gy) of blends containing alanine and either B(OH){sub 3} or Gd{sub 2}O{sub 3} is reported. The sensitivity of the alanine-B(OH){sub 3} blend is comparable to the sensitivity of pure alanine, although its lowest detectable dose, LDD, is smaller ({approx}1.3Gy) than that of pure alanine ({approx}2.9Gy). Alanine with Gd{sub 2}O{sub 3} is about two times more sensitive than pure alanine, and its LDD is 0.8Gy. The better sensitivity and LDD are probably due to the high atomic number (Z=64) of gadolinium, which enhances the interaction probability with photons and, consequently, the radical yield. This study suggests that other high-Z atoms may be useful for increasing the sensitivity of the response of alanine to {gamma}-radiation.

  15. Synergistic antibacterial effects of β-Chloro-L-alanine and phosphomycin on urinary tract isolates of E. coli

    Directory of Open Access Journals (Sweden)

    Nima Hosseini Jazani

    2013-01-01

    Full Text Available Introduction: The aim of this study was the evaluation of the synergistic effect of sub-MIC doses of Phosphomycin with β-Chloro-L-alanine against urinary tract isolates of E. coli. Materials and methods: A total of 40 isolates were collected from urine specimens submitted to the clinical diagnostic Laboratories in Urmia, Iran. The amounts of MIC and MBC for Phosphomycin, β-Chloro-L-alanine or a mixture of 0.5 mM β-Chloro-L-alanine with sub-MIC doses of Phosphomycin were determined and three groups were compared. Results: Of 40 E. coli isolates, 12. 5% were susceptible to all investigated concentrations of phosphomycin and 2. 5% were resistant. The mean MIC value for phosphomycin in the other E. coli isolates was determined as 25. 7± 35. 5 µg/ mL. All of the bacterial isolates were resistant to all investigated concentrations of β-Chloro-L-alanine. Application of β-Chloro-L-alanine and phosphomycin combination decreased the MIC and MBC values in 22. 5% of the isolates. Discussion and conclusion: This study suggests that β-Chloro-L-alanine and phosphomycin combination have in vitro synergistic effect on some isolates of urinary tract E. coli.

  16. Microhydration of Alanine in Gas Phase Studied by Quantum Chemical Method and ABEEMσπ/MM Fluctuating Charge Model

    Institute of Scientific and Technical Information of China (English)

    LU Li-nan; LIU Cui; GONG Li-dong

    2013-01-01

    A fluctuating charge interaction potential function for alanine-water was constructed in the spirit of newly developed ABEEMσπ/MM(atom-bond electronegativity equalization method at the σπ level fused into molecular mechanics).The properties of gaseous neutral alanine-(H2O)n(n=1-7) clusters were systematically investigated by quantum mechanics(QM) and the constructed ABEEMσπ/MM potential,such as conformations,hydrogen bonds (H-bonds),interaction energies,charge distributions,and so on.The results of ABEEMσπ/MM model are in fair agreement with those of QM and available experimental data.For isolated alanine,compared with those of experi-mental structure,the average absolute deviations(AAD) of bond length and bond angle are 0.002 nm and 1.4°,respectively.For alanine-water clusters,the AAD of interaction energies and H-bond lengths are only 3.77 kJ/mol and 0.012 nm,respectively,compared to the results of MP2/aug-cc-pVDZ//MP2/6-311+G** method.The ABEEMσπ charges fluctuate with the changing conformation of the system,and can accurately and reasonably reflect the interpolarization between water and alanine.The presented alanine-water potential function may provide a basis for further simulations on related aqueous solutions of biomolecules.

  17. Characteristics, tissue-specific expression, and hormonal regulation of expression of tyrosine aminotransferase in the avian female reproductive tract.

    Science.gov (United States)

    Lim, W; Song, G

    2016-10-01

    Tyrosine aminotransferase (TAT) catalyzes the transamination of tyrosine to p-hydroxyphenylpyruvate. Accumulation of tyrosine in the body due to a genetic mutation in the TAT gene causes tyrosomia type II in humans. The TAT gene is regarded as a model for studying steroid-inducible factors regulating a variety of biological functions of TAT. However, little is known of the effects of estrogen on the expression of the TAT gene in chickens. Therefore, in the present study, we identified expression of the avian TAT gene in various organs. The results showed the TAT was detected predominantly in the liver and reproductive organs including testis, oviduct, and ovary. Specifically, TAT mRNA was expressed abundantly in the glandular and luminal epithelia of the oviducts in response to endogenous and exogenous estrogens which also induce dramatic morphological changes in the oviduct of chickens. In addition, target microRNAs of TAT (miR-1460, miR-1626-3p, miR-1690-5p, and miR-7442-3p) were found to modulate expression of the TAT gene. Especially, miR-1690-5p influenced TAT gene transcription by binding directly to its 3'-UTR region. Moreover, the expression of TAT was abundant in glandular epithelia of cancerous but not normal ovaries from laying hens. Taken together, our findings suggest that TAT plays an important role in the cytodifferentiation of oviducts in response to estrogen and in the progression of ovarian cancer in chickens. PMID:27295280

  18. Assessment of lactate dehydrogenase, alkaline phosphatase and aspartate aminotransferase activities in cow's milk as an indicator of subclinical mastitis.

    Science.gov (United States)

    Babaei, H; Mansouri-Najand, L; Molaei, M M; Kheradmand, A; Sharifan, M

    2007-05-01

    This study examined the activities of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in the milk of lactating Holstein cows in association with subclinical mastitis (SCM). A total of 94 milk samples were collected from 58 lactating dairy cows representing stages of lactation from the second to the tenth week after calving. Those which were classified as positive by California mastitis test (CMT) were deemed to have subclinical mastitis. All the milk samples were skimmed by centrifugation at 10 000g at 0 degrees C and were used for enzyme activities estimations. The mean activities of LDH and ALP were higher in the milk from udders with SCM than in the milk from healthy udders (p CMT results and LDH and ALP values were seen at thresholds of > 180 IU/L and > 40 IU/L respectively (kappa values 0.65 and 0.79, respectively). However, the sensitivity of the tests for identifying SCM at these thresholds was higher for ALP (96.4%) than for LDH (68.5%). In this study, LDH and ALP tests were standardized for cow's milk and results showed that only the ALP test was reliable in the early diagnosis of subclinical mastitis. PMID:17268916

  19. Comparative study of glycine, alanine or casein as inert nitrogen sources in endotoxemic rats.

    Science.gov (United States)

    Chambon-Savanovitch, C; Felgines, C; Farges, M C; Raul, F; Cézard, J P; Davot, P; Vasson, M P; Cynober, L A

    1999-10-01

    Pharmacological effects of dietary amino acids (AA) and peptides must be compared to an isonitrogenous control that is as inert as possible. To establish a rationale for the choice of such a control, potential metabolic and nutritional effects of three currently used nitrogenous controls (glycine, alanine, and casein) were evaluated in an endotoxemic rat model that has well-defined alterations in AA and protein metabolism. Five-week-old male Sprague-Dawley rats (113 +/- 1 g) were randomly assigned to four groups and received at d 0 an intraperitoneal injection of endotoxin (3 mg/kg). After withdrawal of food for 24 h, the rats were enterally refed for 48 h with a liquid diet (Osmolite((R))) supplemented with 0.19 g N. kg(-1). d(-1) in the form of glycine [lipopolysaccharide (LPS)-GLY group], alanine (LPS-ALA group) or casein (LPS-CAS group). One group (LPS group) received only Osmolite((R)). Plasma, two skeletal muscles, the liver and the intestine were then removed. Body and tissue weights and tissue protein contents did not differ among the four groups. Intestine histomorphometry showed no significant difference among groups. Jejunal hydrolase activities were significantly affected by the nitrogenous supplementations, but no effect was observed in the ileum. Only limited significant effects were observed on plasma and tissue-free AA concentrations, except for an accumulation of glycine in the plasma and tissues from the LPS-GLY group, compared to other groups. Overall, whereas glycine as a nitrogenous control should be used with care, either alanine or casein may be used as the "placebo," with the choice depending on the study to be performed. PMID:10498760

  20. Effects of β-Alanine on Body Composition and Performance Measures in Collegiate Women.

    Science.gov (United States)

    Outlaw, Jordan J; Smith-Ryan, Abbie E; Buckley, Amanda L; Urbina, Stacie L; Hayward, Sara; Wingfield, Hailee L; Campbell, Bill; Foster, Cliffa; Taylor, Lem W; Wilborn, Colin D

    2016-09-01

    Outlaw, JJ, Smith-Ryan, AE, Buckley, AL, Urbina, SL, Hayward, S, Wingfield, HL, Campbell, B, Foster, C, Taylor, LW, and Wilborn, CD. Effects of β-alanine on body composition and performance measures in collegiate women. J Strength Cond Res 30(9): 2627-2637, 2016-The purpose of this study was to evaluate the effects of β-alanine (BA) supplementation and resistance training on body composition and performance. In a double-blind placebo-controlled design, 16 untrained collegiate females (mean ± SD: 21.0 ± 2.2 years; 64.8 ± 8.5 kg; 164.5 ± 7.0 cm; 30.1 ± 5.1 percent body fat [%BF]) completed 8 weeks of resistance training while consuming either 3.4 g BA or placebo (PL; 5 g maltodextrin) before training sessions. Training consisted of 4 days per week upper- and lower-body exercises. Lean body mass (LBM), fat mass (FM), and %BF were assessed using dual-energy x-ray absorptiometry. Maximal oxygen consumption (V[Combining Dot Above]O2max), aerobic time to exhaustion, Wingate peak power, bench press and leg press 1RM (BPmax; LPmax), and repetitions at 65% (BPreps; LPreps), vertical jump (VJ), and standing broad jump were assessed using standard National Strength and Conditioning Association guidelines. All measurements were taken at baseline (T1), 4 weeks (T2), and 8 weeks (T3). Repeated-measures analysis of variance and 95% confidence intervals were used to determine significance. Body composition (LBM, FM, and %BF) improved over time (p supplementation may be effective for improving lower-body muscular endurance. β-alanine had no additive effects on body composition or maximal strength in collegiate women. PMID:25486294

  1. Radical formation in the radiolysis of solid alanine by heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, H. [Hokkaido Univ., Sapporo (Japan). Graduate Sch. of Eng.; Ichikawa, T. [Hokkaido Univ., Sapporo (Japan). Graduate Sch. of Eng.; Yoshida, H. [Hokkaido Univ., Sapporo (Japan). Graduate Sch. of Eng.; Namba, H. [Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute, 1233 Watanuki-machi, Takasaki, Gunma 370-12 (Japan); Taguchi, M. [Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute, 1233 Watanuki-machi, Takasaki, Gunma 370-12 (Japan); Kojima, T. [Takasaki Radiation Chemistry Research Establishment, Japan Atomic Energy Research Institute, 1233 Watanuki-machi, Takasaki, Gunma 370-12 (Japan)

    1996-10-01

    Radical formation in solid {alpha}-alanine irradiated with 175-MeV Ar{sup 8+} and 460-MeV Ar{sup 13+}, 220-MeV C{sup 5+}, and 350-MeV Ne{sup 8+} ions were studied by the ESR method. The radical yield (number of radicals per incident ion) is constant below the critical fluence of about 10{sup 10} ions cm{sup -2} for the Ar ions, 10{sup 11} ions cm{sup -2} for the C ion, and 5.10{sup 11} ions cm{sup -2} for the Ne ion. Above the critical fluence, the yield decreases with increasing ion fluence. G-value of the radical formation was obtained from the constant yield at the low fluences. The G-value is not a simple function of LET. This is ascribed to the difference in lateral dose distribution of ion tracks. Assuming a simple cylindrical shape of the ion tracks, the average dose in and the radius of the ion tracks were estimated from the G-values. The radius is 8-25 nm, which is larger than the radius of 2-5 nm for 0.5-3 MeV H{sup +} and He{sup +} ion-irradiations. The fluence-yield curves were simulated with the cylindrical tracks and with the dose-yield relationship for the radical formation in {gamma}-irradiated alanine. The simulated curves agree well with the experimental ones. With the cylindrical model of ion tracks, the variation of the radical yield at the high fluences can be estimated for solid alanine irradiated with several hundreds of MeV heavy ions. (orig.).

  2. Study of alanine-cadmium complexes in water-alcohol mixtures

    International Nuclear Information System (INIS)

    Alanine complexes of cadmium have been studied polarographically in aqueous and water-alcohol mixtures. A reversible reduction was observed in aqueous and 20% water-alcohol mixtures (i.e. 20% methanol or ethanol) and hence the stability constants were evaluated using Deford and Hume's method while in the case of 40% water-alcohol mixtures (.i.e. 40% methanol or ethanol) the reduction was quasireversible. The formal potentials were obtained by Gellings method. It was found that the decrease in dielectric constant favours greater association of ions resulting in higher value of stability constants. (author)

  3. Is there an influence of the surrounding material on the response of the alanine dosimetry system?

    Science.gov (United States)

    Anton, Mathias; Kapsch, Ralf-Peter; Hackel, Thomas

    2009-04-01

    In a combined experimental and Monte Carlo study the possible influence of the surrounding material on the response of the alanine dosimetry system was investigated. The aim of this work was to estimate the uncertainties induced by the surroundings with respect to quality assurance measurements for radiotherapy, for example in humanoid phantoms. Six different materials were tested. The electron density range covered comprises the range present in human tissue. No significant influence of the surrounding material could be found for irradiations in the 60Co reference field of the Physikalisch-Technische Bundesanstalt (PTB).

  4. Small-Field Dosimetry in A 6 MV Photon Beam Using Alanine and Liquid Ionisation Chamber

    DEFF Research Database (Denmark)

    Zimmermann, S.; Riis, H. L.; Hjelm-Hansen, M.;

    2012-01-01

    Purpose/Objective: Dosimetry of small field sizes in MV photon beams is an increasingly important subject, and a generally accepted guideline for clinical measurements is still lacking. The present comparative study was carried out to further investigate the use of alanine and the PTW microLion...... of each field and depth. This dose maximum was measured for each field using a Scanditronix Wellhöfer photon field diode. The same measurements were carried out using a liquid ionchamber, PTW microLion, irradiated by 500 MU. The output of the accelerator was controlled by a PTW semiflex ion chamber...

  5. GMXPBSA 2.1: A GROMACS tool to perform MM/PBSA and computational alanine scanning

    Science.gov (United States)

    Paissoni, C.; Spiliotopoulos, D.; Musco, G.; Spitaleri, A.

    2015-01-01

    GMXPBSA 2.1 is a user-friendly suite of Bash/Perl scripts for streamlining MM/PBSA calculations on structural ensembles derived from GROMACS trajectories, to automatically calculate binding free energies for protein-protein or ligand-protein complexes [R.T. Bradshaw et al., Protein Eng. Des. Sel. 24 (2011) 197-207]. GMXPBSA 2.1 is flexible and can easily be customized to specific needs and it is an improvement of the previous GMXPBSA 2.0 [C. Paissoni et al., Comput. Phys. Commun. (2014), 185, 2920-2929]. Additionally, it performs computational alanine scanning (CAS) to study the effects of ligand and/or receptor alanine mutations on the free energy of binding. Calculations require only for protein-protein or protein-ligand MD simulations. GMXPBSA 2.1 performs different comparative analyses, including a posteriori generation of alanine mutants of the wild-type complex, calculation of the binding free energy values of the mutant complexes and comparison of the results with the wild-type system. Moreover, it compares the binding free energy of different complex trajectories, allowing the study of the effects of non-alanine mutations, post-translational modifications or unnatural amino acids on the binding free energy of the system under investigation. Finally, it can calculate and rank relative affinity to the same receptor utilizing MD simulations of proteins in complex with different ligands. In order to dissect the different MM/PBSA energy contributions, including molecular mechanic (MM), electrostatic contribution to solvation (PB) and nonpolar contribution to solvation (SA), the tool combines two freely available programs: the MD simulations software GROMACS [S. Pronk et al., Bioinformatics 29 (2013) 845-854] and the Poisson-Boltzmann equation solver APBS [N.A. Baker et al., Proc. Natl. Acad. Sci. U.S.A 98 (2001) 10037-10041]. All the calculations can be performed in single or distributed automatic fashion on a cluster facility in order to increase the

  6. β-Alanine ingestion increases muscle carnosine content and combat specific performance in soldiers

    OpenAIRE

    Hoffman, Jay R; Landau, Geva; Stout, Jeffrey R.; Hoffman, Mattan W.; Shavit, Nurit; Rosen, Philip; Moran, Daniel S.; Fukuda, David H.; Shelef, Ilan; Carmom, Erez; Ostfeld, Ishay

    2014-01-01

    The purpose of this study was to examine the effect of β-alanine (BA) ingestion on tissue carnosine levels and the impact such changes would have on combat specific activity. Eighteen soldiers (19.9 ± 0.8 year) from an elite combat unit were randomly assigned to either a BA or placebo (PL) group. Before and following a 30-day supplementation period carnosine content of the gastrocnemius muscle and brain was determined by proton magnetic resonance spectroscopy. During each testing session, par...

  7. Functionalization of single-walled carbon nanotubes with uracil, guanine, thymine and L-alanine

    Science.gov (United States)

    Silambarasan, D.; Iyakutti, K.; Vasu, V.

    2014-06-01

    Experimental investigation of functionalization of oxidized single-walled carbon nanotubes (OSWCNTs) with three nucleic acid bases such as uracil, guanine, thymine and one amino acid, L-alanine is carried out. Initially, the SWCNTs are oxidized by acid treatment. Further, the oxidized SWCNTs are effectively functionalized with aforementioned biological compounds by ultrasonication. The diameter of OSWCNTs has increased after the adsorption of biological compounds. The cumulative Π-Π stacking, hydrogen bond and polar interaction are the key factors to realize the adsorption. The amount of adsorption of each biological compound is estimated. The adsorption of guanine is more among all the four biological compounds.

  8. Theoretical investigation of radical species formed from L-α-alanine under gamma-irradiation

    International Nuclear Information System (INIS)

    Gamma-irradiated L-α-alanine used in EPR-coupled dosimetry has a complex EPR spectrum at room temperature. Changing the temperature or other conditions of the irradiated samples leads to varied EPR spectrum, i.e., some components disappear and/or new ones are formed. We used both molecular mechanics (MM+) and semiempirical (AM1) methods to perform a theoretical investigation of the seven radical species that have been experimentally detected. We established their order of priority in the given simulation conditions (at 0 K, in vacuo). The formation stages advanced for these long-lived radical species were characterized by a theoretical determination of the reaction enthalpies. (author)

  9. Anomalous temperature dependence in the Raman spectra of l-alanine: Evidence for dynamic localization

    Energy Technology Data Exchange (ETDEWEB)

    Migliori, A.; Maxton, P.M.; Clogston, A.M.; Zirngiebl, E.; Lowe, M.

    1988-12-15

    We measured the temperature dependence of the intensity of the two lowest Raman modes in single crystals of l-alanine. The sum of the intensities obeys Maxwell-Boltzman statistics accurately from 20 to 340 K but the intensities of the individual lines are anomalous. This behavior is explained by assuming that both lines share the same degrees of freedom but that a mode instability is triggered abruptly at an occupation of seven quanta. This instability, which has an activation energy of 500 K, is observed at temperatures as low as 20 K, possibly indicating the existence of dynamic localization of vibrational energy.

  10. Study of solid-state isotopic exchange of hydrogen in L-alanine

    International Nuclear Information System (INIS)

    The solid-state isotopic exchange of L-Ala with the spillover tritium activated on Rh(Pd) supported catalysts and the reactivity of hydrogen at C(2) and C(3) carbon atoms of L-Ala were studied using tritium NMR. The activation energy of the catalyzed isotopic exchange was measured. Ab initio calculations of the reaction of hydrogen exchange in the alanine molecule with H3O+ ion were carried out. The mechanism and transition states of this reaction were proposed. 22 refs.; 4 figs.; 4 tabs

  11. Design of Deinococcus radiodurans thioredoxin reductase with altered thioredoxin specificity using computational alanine mutagenesis

    OpenAIRE

    Obiero, Josiah; Sanders, David AR

    2011-01-01

    In this study, the X-ray crystal structure of the complex between Escherichia coli thioredoxin reductase (EC TrxR) and its substrate thioredoxin (Trx) was used as a guide to design a Deinococcus radiodurans TrxR (DR TrxR) mutant with altered Trx specificity. Previous studies have shown that TrxRs have higher affinity for cognate Trxs (same species) than that for Trxs from different species. Computational alanine scanning mutagenesis and visual inspection of the EC TrxR–Trx interface suggested...

  12. Kynurenine aminotransferase III and glutamine transaminase L are identical enzymes that have cysteine S-conjugate β-lyase activity and can transaminate L-selenomethionine.

    Science.gov (United States)

    Pinto, John T; Krasnikov, Boris F; Alcutt, Steven; Jones, Melanie E; Dorai, Thambi; Villar, Maria T; Artigues, Antonio; Li, Jianyong; Cooper, Arthur J L

    2014-11-01

    Three of the four kynurenine aminotransferases (KAT I, II, and IV) that synthesize kynurenic acid, a neuromodulator, are identical to glutamine transaminase K (GTK), α-aminoadipate aminotransferase, and mitochondrial aspartate aminotransferase, respectively. GTK/KAT I and aspartate aminotransferase/KAT IV possess cysteine S-conjugate β-lyase activity. The gene for the former enzyme, GTK/KAT I, is listed in mammalian genome data banks as CCBL1 (cysteine conjugate beta-lyase 1). Also listed, despite the fact that no β-lyase activity has been assigned to the encoded protein in the genome data bank, is a CCBL2 (synonym KAT III). We show that human KAT III/CCBL2 possesses cysteine S-conjugate β-lyase activity, as does mouse KAT II. Thus, depending on the nature of the substrate, all four KATs possess cysteine S-conjugate β-lyase activity. These present studies show that KAT III and glutamine transaminase L are identical enzymes. This report also shows that KAT I, II, and III differ in their ability to transaminate methyl-L-selenocysteine (MSC) and L-selenomethionine (SM) to β-methylselenopyruvate (MSP) and α-ketomethylselenobutyrate, respectively. Previous studies have identified these seleno-α-keto acids as potent histone deacetylase inhibitors. Methylselenol (CH3SeH), also purported to have chemopreventive properties, is the γ-elimination product of SM and the β-elimination product of MSC catalyzed by cystathionine γ-lyase (γ-cystathionase). KAT I, II, and III, in part, can catalyze β-elimination reactions with MSC generating CH3SeH. Thus, the anticancer efficacy of MSC and SM will depend, in part, on the endogenous expression of various KAT enzymes and cystathionine γ-lyase present in target tissue coupled with the ability of cells to synthesize in situ either CH3SeH and/or seleno-keto acid metabolites.

  13. Evaluation of Milk Trace Elements, Lactate Dehydrogenase, Alkaline Phosphatase and Aspartate Aminotransferase Activity of Subclinical Mastitis as and Indicator of Subclinical Mastitis in Riverine Buffalo (Bubalus bubalis)

    OpenAIRE

    Guha, Anirban; Gera, Sandeep; Sharma, Anshu

    2012-01-01

    Mastitis is a highly morbid disease that requires detection at the subclinical stage. Tropical countries like India mainly depend on milch buffaloes for milk. The present study was conducted to investigate whether the trace minerals viz. copper (Cu), iron (Fe), zinc (Zn), cobalt (Co) and manganese (Mn) and enzyme activity of lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in riverine buffalo milk can be used as an indicator of subclinical mastitis ...

  14. Crystal structures of the PLP- and PMP-bound forms of BtrR, a dual functional aminotransferase involved in butirosin biosynthesis.

    Science.gov (United States)

    Popovic, Bojana; Tang, Xiao; Chirgadze, Dimitri Y; Huang, Fanglu; Blundell, Tom L; Spencer, Jonathan B

    2006-10-01

    The aminotransferase (BtrR), which is involved in the biosynthesis of butirosin, a 2-deoxystreptamine (2-DOS)-containing aminoglycoside antibiotic produced by Bacillus circulans, catalyses the pyridoxal phosphate (PLP)-dependent transamination reaction both of 2-deoxy-scyllo-inosose to 2-deoxy-scyllo-inosamine and of amino-dideoxy-scyllo-inosose to 2-DOS. The high-resolution crystal structures of the PLP- and PMP-bound forms of BtrR aminotransferase from B. circulans were solved at resolutions of 2.1 A and 1.7 A with R(factor)/R(free) values of 17.4/20.6 and 19.9/21.9, respectively. BtrR has a fold characteristic of the aspartate aminotransferase family, and sequence and structure analysis categorises it as a member of SMAT (secondary metabolite aminotransferases) subfamily. It exists as a homodimer with two active sites per dimer. The active site of the BtrR protomer is located in a cleft between an alpha helical N-terminus, a central alphabetaalpha sandwich domain and an alphabeta C-terminal domain. The structures of the PLP- and PMP-bound enzymes are very similar; however BtrR-PMP lacks the covalent bond to Lys192. Furthermore, the two forms differ in the side-chain conformations of Trp92, Asp163, and Tyr342 that are likely to be important in substrate selectivity and substrate binding. This is the first three-dimensional structure of an enzyme from the butirosin biosynthesis gene cluster.

  15. Efficient, Antibiotic Marker-Free Transformation of a Dicot and a Monocot Crop with Glutamate 1-Semialdehyde Aminotransferase Selectable Marker Genes.

    Science.gov (United States)

    Ferradini, Nicoletta; Giancaspro, Angelica; Nicolia, Alessandro; Gadaleta, Agata; Veronesi, Fabio; Rosellini, Daniele

    2016-01-01

    Antibiotic-free, efficient in vitro selection in plant genetic engineering can improve risk perception and speed up pre-market scrutiny of genetically modified crops. We provide a protocol for genetic transformation of two important crops, durum wheat and alfalfa, using a bacterial and a plant-derived selectable marker gene encoding mutated, gabaculine-insensitive glutamate 1-semialdehyde aminotransferase (GSA) enzymes. These methods can potentially be applied, with minor adaptations, to many other monocot and dicot crop plants. PMID:26614283

  16. Offer/Acceptance Ratio.

    Science.gov (United States)

    Collins, Mimi

    1997-01-01

    Explores how human resource professionals, with above average offer/acceptance ratios, streamline their recruitment efforts. Profiles company strategies with internships, internal promotion, cooperative education programs, and how to get candidates to accept offers. Also discusses how to use the offer/acceptance ratio as a measure of program…

  17. Compression Ratio Adjuster

    Science.gov (United States)

    Akkerman, J. W.

    1982-01-01

    New mechanism alters compression ratio of internal-combustion engine according to load so that engine operates at top fuel efficiency. Ordinary gasoline, diesel and gas engines with their fixed compression ratios are inefficient at partial load and at low-speed full load. Mechanism ensures engines operate as efficiently under these conditions as they do at highload and high speed.

  18. Detecting isotopic ratio outliers

    International Nuclear Information System (INIS)

    An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers. 6 refs., 3 figs., 3 tabs

  19. Financial Key Ratios

    Directory of Open Access Journals (Sweden)

    Tănase Alin-Eliodor

    2014-08-01

    Full Text Available This article focuses on computing techniques starting from trial balance data regarding financial key ratios. There are presented activity, liquidity, solvency and profitability financial key ratios. It is presented a computing methodology in three steps based on a trial balance.

  20. Specialized ratio analysis.

    Science.gov (United States)

    Wyer, J C; Salzinger, F H

    1983-01-01

    Many common management techniques have little use in managing a medical group practice. Ratio analysis, however, can easily be adapted to the group practice setting. Acting as broad-gauge indicators, financial ratios provide an early warning of potential problems and can be very useful in planning for future operations. The author has gathered a collection of financial ratios which were developed by participants at an education seminar presented for the Virginia Medical Group Management Association. Classified according to the human element, system component, and financial factor, the ratios provide a good sampling of measurements relevant to medical group practices and can serve as an example for custom-tailoring a ratio analysis system for your medical group.

  1. Cloning, purification, crystallization and preliminary X-ray crystallographic analysis of the biosynthetic N-acetylornithine aminotransferases from Salmonella typhimurium and Escherichia coli

    International Nuclear Information System (INIS)

    Acetylornithine aminotransferases, members of the type I subgroup II family of PLP-dependent enzymes, from S. typhimurium and E. coli have been cloned, overexpressed, purified and crystallized. Acetylornithine aminotransferase (AcOAT) is a type I pyridoxal 5′-phosphate-dependent enzyme catalyzing the conversion of N-acetylglutamic semialdehyde to N-acetylornithine in the presence of α-ketoglutarate, a step involved in arginine metabolism. In Escherichia coli, the biosynthetic AcOAT also catalyzes the conversion of N-succinyl-l-2-amino-6-oxopimelate to N-succinyl-l,l-diaminopimelate, one of the steps in lysine biosynthesis. It is closely related to ornithine aminotransferase. AcOAT was cloned from Salmonella typhimurium and E. coli, overexpressed in E. coli and purified using Ni–NTA affinity column chromatography. The enzymes crystallized in the presence of gabaculine. Crystals of E. coli AcOAT (eAcOAT) only diffracted X-rays to 3.5 Å and were twinned. The crystals of S. typhimurium AcOAT (sAcOAT) diffracted to 1.9 Å and had a dimer in the asymmetric unit. The structure of sAcOAT was solved by the molecular-replacement method

  2. Cloning, purification, crystallization and preliminary X-ray crystallographic analysis of the biosynthetic N-acetylornithine aminotransferases from Salmonella typhimurium and Escherichia coli

    Energy Technology Data Exchange (ETDEWEB)

    Rajaram, V.; Prasad, K.; Ratna Prasuna, P.; Ramachandra, N.; Bharath, S. R. [Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012 (India); Savithri, H. S. [Department of Biochemistry, Indian Institute of Science, Bangalore 560 012 (India); Murthy, M. R. N., E-mail: mrn@mbu.iisc.ernet.in [Molecular Biophysics Unit, Indian Institute of Science, Bangalore 560 012 (India)

    2006-10-01

    Acetylornithine aminotransferases, members of the type I subgroup II family of PLP-dependent enzymes, from S. typhimurium and E. coli have been cloned, overexpressed, purified and crystallized. Acetylornithine aminotransferase (AcOAT) is a type I pyridoxal 5′-phosphate-dependent enzyme catalyzing the conversion of N-acetylglutamic semialdehyde to N-acetylornithine in the presence of α-ketoglutarate, a step involved in arginine metabolism. In Escherichia coli, the biosynthetic AcOAT also catalyzes the conversion of N-succinyl-l-2-amino-6-oxopimelate to N-succinyl-l,l-diaminopimelate, one of the steps in lysine biosynthesis. It is closely related to ornithine aminotransferase. AcOAT was cloned from Salmonella typhimurium and E. coli, overexpressed in E. coli and purified using Ni–NTA affinity column chromatography. The enzymes crystallized in the presence of gabaculine. Crystals of E. coli AcOAT (eAcOAT) only diffracted X-rays to 3.5 Å and were twinned. The crystals of S. typhimurium AcOAT (sAcOAT) diffracted to 1.9 Å and had a dimer in the asymmetric unit. The structure of sAcOAT was solved by the molecular-replacement method.

  3. Cloning of a novel phosphateserine aminotransferase gene from a Triticum aestivum-Elytrigia elongatum alien substitution line with resistance to powdery mildew

    Institute of Scientific and Technical Information of China (English)

    HE Daoyi; WANG Honggang

    2005-01-01

    Shannong 551, a T. aestivum-E. elongatum alien substitution line with resistance to powdery mildew, was inoculated with pathogenic spores of powdery mildew. The leaf samples were prepared 48 h after inoculation for scanning electron microscopy. The result showed that germination of spores and growth of young mycelia on leaves of Shannong 551 were suppressed at the early stage of infection. At the same time, RNAs were prepared from the leaves for the cloning of WRP1 and RPW2 by cDNA RDA and RACE technology. BLAST analysis of the sequences indicated that both WRP1 and RPW2 were novel genes. WRP1 contains no complete ORF. RPW2 contains the conserved structure domain of aminotransferase, and its DNA sequence shares high homology with genes of phosphateserine aminotransferase in many organisms. Therefore, it is speculated as a novel phosphateserine aminotransferase gene. The results of Northern blot suggested that expression of RPW2 occurred at the early stage of infection by powdery mildew. Southern blot using the probe of RPW2, in which there was strong hybridizing signals in both genome of Shannong 551 and E. elongatum, but not in those of Jinan 13 and Lumai No.5, indicated that RPW2 derived from the genome of E. elongatum.

  4. Role of tRNAPro in pretransfer editing of alanine by prolyl-tRNA synthetase

    Directory of Open Access Journals (Sweden)

    Boyarshin K. S.

    2013-09-01

    Full Text Available Aim. To characterize the process of tRNA-dependent pretransfer edi- ting of alanine by prolyl-tRNA synthetase of bacteria Enterococcus faecalis (ProRSEf. Methods. Velocity of the editing processes in vitro was determined by ATP hydrolysis by ProRSEf. Pretransfer and posttransfer editing were experimentally separated by site-directed mutagenesis. Results. tRNA-dependent pretransfer editing is characterized by three-fold larger velocity then tRNA-independent editing. Effectivity of the process depends on the presence of 2'-hydroxyle group of A76 tRNAPro. In the absence of tRNAPro selective release of alanyl-AMP occurs simultaneously with tRNA-independent pretransfer editing. Released alanyl-AMP can be re-bound and hydrolyzed. Conclusions. tRNA-dependent pretransfer editing of alanine by ProRSEf is the catalytic mechanism, mediated by 2'-hydroxyl group of A76 tRNAPro. In the absence of tRNAPro tRNA-independent pretransfer editing and selective release of alanyl-AMP occur.

  5. Direct detection of second harmonic and its use in alanine/EPR dosimetry

    International Nuclear Information System (INIS)

    In this work, the possible use of the second harmonic EPR signal from irradiated alanine for low radiation dose (∼1 Gy) was explored, aiming applications to HDR brachytherapy and teletherapy. The second harmonic signal was directly detected after overmodulation. A batch of DL-alanine/paraffin small cylindrical pellets was made. A VARIAN E-4 X-Band EPR spectrometer with optimized operation parameters like microwave power and modulation amplitude to obtain a signal with the highest amplitude was used. The modulation frequency and modulation amplitude were 100 kHz and 1.25 mT (to overmodulate the signal) respectively. The second harmonic signal was directly detected at twice the modulation frequency. One group of dosimeters was irradiated with a 192 Ir brachytherapy source and the other in a 10 MeV X-rays linear accelerator, both group at a dose range: 0.5 - 15 Gy. The second harmonic signal showed better resolution than the first harmonic one making possible a more easy localization of the signal. Moreover, for both types of radiation, the dose-response curve showed a good linear behavior for the dose range indicated. (author)

  6. Characterization and biocompatibility of organogels based on L-alanine for parenteral drug delivery implants.

    Science.gov (United States)

    Motulsky, Aude; Lafleur, Michel; Couffin-Hoarau, Anne-Claude; Hoarau, Didier; Boury, Frank; Benoit, Jean-Pierre; Leroux, Jean-Christophe

    2005-11-01

    The development of simple and efficient drug delivery systems for the sustained release of peptides/proteins and low molecular weight hydrophilic molecules is an ongoing challenge. The purpose of this work was to prepare and characterize novel biodegradable in situ-forming implants obtained via the self-assembly of L-alanine derivatives in pharmaceutical oils. Six different amphiphilic organogelators based on L-alanine were synthesized. These derivatives could successfully gel various vegetable and synthetic oils approved for parenteral administration. Gelation was thermoreversible, and phase transition temperatures depended on gelator structure, concentration and solvent. Hydrogen bonds and van der Waals interactions were shown to be the main forces implicated in network formation. Selected formulations were then injected subcutaneously in rats for preliminary assessment of biocompatibility. Histopathological analysis of the surrounding tissues revealed mild, chronic inflammation and an overall good biocompatibility profile of the implants over the 8 wk evaluation period. This study demonstrates that in situ-forming organogels represent a potentially promising platform for sustained drug delivery.

  7. Densities, viscosities, refractive indices, and electrical conductivities of aqueous alkali salts of α-alanine

    International Nuclear Information System (INIS)

    Highlights: • Thermophysical properties of aqueous Na and K salts of α-alanine were studied. • Properties are density, viscosity, refractive indices, and thermal conductivity. • The concentrations of amino acid salt ranges from (0.5 to 3.5) M. • The temperature range studied was (333.15 to 343.15) K. • The measured data were represented satisfactorily by using the applied correlations. - Abstract: In this work, physicochemical properties such as density, viscosity, refractive index, and electrical conductivity of aqueous alkali (potassium or sodium) salts of the amino acid α-alanine (ALA), were measured at temperatures from (303.15 to 343.15) K and concentrations ranging from (0.5 to 3.5) M. Density and viscosity measurements were performed using the vibrating tube and the falling ball techniques, respectively. The refractive index at the sodium D line was measured in an automatic refractometer, while the electrical conductivity was measured using a commercial conductivity meter. An empirical equation was applied to correlate the density, refractive index, and electrical conductivity of the amino acid salt solutions with temperature and amino acid salt concentration, which gave average absolute deviation values of 0.03%, 0.01%, and 0.6%, respectively. The variation of the viscosity as a function of temperature and amino acid salt concentration was accurately represented by a modified Vogel–Tamman–Fulcher equation at an average absolute deviation of 0.5%

  8. L,L-diaminopimelate aminotransferase (DapL: A putative target for the development of narrow-spectrum antibacterial compounds

    Directory of Open Access Journals (Sweden)

    Alexander J Triassi

    2014-09-01

    Full Text Available Despite the urgent need for sustained development of novel antibacterial compounds to combat the drastic rise in antibiotic resistant and emerging bacterial infections, only a few clinically relevant antibacterial drugs have been recently developed. One of the bottlenecks impeding the development of novel antibacterial compounds is the identification of new enzymatic targets. The nutritionally essential amino acid anabolic pathways, for example lysine biosynthesis, provide an opportunity to explore the development of antibacterial compounds, since human genomes do not possess the genes necessary to synthesize these amino acids de novo. The diaminopimelate (DAP/lysine (lys anabolic pathways are attractive targets for antibacterial development since the penultimate lys precursor meso-DAP (m-DAP is a cross-linking amino acid in the peptidoglycan (PG cell wall of most Gram-negative bacteria and lys plays a similar role in the PG of most Gram-positive bacteria, in addition to its role as one of the 20 proteogenic amino acids. The L,L-diaminopimelate aminotransferase (DapL pathway was recently identified as a novel variant of the DAP/lys anabolic pathways. The DapL pathway has been identified in the pathogenic bacteria belonging to the genus; Chlamydia, Leptospira and Treponema. The dapL gene has been identified in the genomes of 381 or approximately 13% of the 2,771 bacteria that have been sequenced, annotated and reposited in the NCBI database, as of May 23, 2014. The narrow distribution of the DapL pathway in the bacterial domain provides an opportunity for the development and or discovery of narrow spectrum antibacterial compounds.

  9. Saccharomyces cerevisiae Bat1 and Bat2 aminotransferases have functionally diverged from the ancestral-like Kluyveromyces lactis orthologous enzyme.

    Directory of Open Access Journals (Sweden)

    Maritrini Colón

    Full Text Available BACKGROUND: Gene duplication is a key evolutionary mechanism providing material for the generation of genes with new or modified functions. The fate of duplicated gene copies has been amply discussed and several models have been put forward to account for duplicate conservation. The specialization model considers that duplication of a bifunctional ancestral gene could result in the preservation of both copies through subfunctionalization, resulting in the distribution of the two ancestral functions between the gene duplicates. Here we investigate whether the presumed bifunctional character displayed by the single branched chain amino acid aminotransferase present in K. lactis has been distributed in the two paralogous genes present in S. cerevisiae, and whether this conservation has impacted S. cerevisiae metabolism. PRINCIPAL FINDINGS: Our results show that the KlBat1 orthologous BCAT is a bifunctional enzyme, which participates in the biosynthesis and catabolism of branched chain aminoacids (BCAAs. This dual role has been distributed in S. cerevisiae Bat1 and Bat2 paralogous proteins, supporting the specialization model posed to explain the evolution of gene duplications. BAT1 is highly expressed under biosynthetic conditions, while BAT2 expression is highest under catabolic conditions. Bat1 and Bat2 differential relocalization has favored their physiological function, since biosynthetic precursors are generated in the mitochondria (Bat1, while catabolic substrates are accumulated in the cytosol (Bat2. Under respiratory conditions, in the presence of ammonium and BCAAs the bat1Δ bat2Δ double mutant shows impaired growth, indicating that Bat1 and Bat2 could play redundant roles. In K. lactis wild type growth is independent of BCAA degradation, since a Klbat1Δ mutant grows under this condition. CONCLUSIONS: Our study shows that BAT1 and BAT2 differential expression and subcellular relocalization has resulted in the distribution of the

  10. Characterization of five putative aspartate aminotransferase genes in the N2-fixing heterocystous cyanobacterium Anabaena sp. strain PCC 7120.

    Science.gov (United States)

    Xu, Xinyi; Gu, Liping; He, Ping; Zhou, Ruanbao

    2015-06-01

    Aspartate and glutamate are two key amino acids used in biosynthesis of many amino acids that play vital role in cellular metabolism. Aspartate aminotransferases (AspATs) are required for channelling nitrogen (N(2)) between Glu and Asp in all life forms. Biochemical and genetic characterization of AspATs have been lacking in N(2)-fixing cyanobacteria. In this report, five putative AspAT genes (alr1039, all2340, alr2765, all4327 and alr4853) were identified in the N(2)-fixing heterocystous cyanobacterium Anabaena sp. PCC 7120. Five recombinant C-terminal hexahistidine-tagged AspATs (AspAT-H(6)) were overexpressed in Escherichia coli and purified to homogeneity. Biochemical analysis demonstrated that these five putative AspATs have authentic AspAT activity in vitro using aspartate as an amino donor. However, the enzymic activities of the five AspATs differed in vitro. Alr4853-H(6) showed the highest AspAT activity, while the enzymic activity for the other four AspATs ranged from 6.5 to 53.7 % activity compared to Alr4853 (100 %). Genetic characterization of the five AspAT genes was also performed by inactivating each individual gene. All of the five AspAT knockout mutants exhibited reduced diazotrophic growth, and alr4853 was further identified to be a Fox gene (requiring fixed N(2) for growth in the presence of oxygen). Four out of five P(aspAT)-gfp transcriptional fusions were constitutively expressed in both diazotrophic and nitrate-dependent growth conditions. Quantitative reverse transcriptase PCR showed that alr4853 expression was increased by 2.3-fold after 24 h of N(2) deprivation. Taken together, these findings add to our understanding of the role of AspATs in N(2)-fixing within heterocystous cyanobacteria.

  11. A non-enzymic browning induced by gamma cobalt-60 irradiation and heating in a fructose-alanine model system

    International Nuclear Information System (INIS)

    The Maillard browning reaction between reducing sugars and amino compounds is important in food chemistry and may considerably affect the colour, aroma and nutritional value of food after thermal processing. In this study, the effect of irradiation combined with heating on the course of browning reaction in the model system of aqueous solution of fructose (0.03M) and alanine (0.01M) was investigated. The optical absorption spectra recorded for irradiated and heated solution of fructose-alanine were different from those of only irradiated or only heated solution. The brown colour of the samples is caused by the extension of the tail-end absorption into the visible region of the spectrum. No absorption maximum appears in the visible range. The heating of irradiated fructose solution with non-irradiated alanine develops markedly more intensive browning than that of the heating of irradiated alanine solution with non-irradiated fructose. The products of fructose radiolysis are responsible for the acceleration of browning in the fructose-alanine system. (author)

  12. A Non-Enzymic Browning Induced by Gamma Cobalt-60 Irradiation and Heating in a Fructose-Alanine Model System

    International Nuclear Information System (INIS)

    The Maillard browning reaction between reducing sugars and amino compounds is important in food chemistry and may considerably affect the colour, aroma and nutritional value of food after thermal processing. In this study, the effect of irradiation combined with heating on the course of browning reaction in the model system of aqueous solution of fructose (0.03M) and alanine (0.01M) was investigated. The optical absorption spectra recorded for irradiated and heated solution of fructose-alanine were different from those of only irradiated or only heated solution. The brown colour of the samples is caused by the extension of the tail-end absorption into the visible region of the spectrum. No absorption maximum appears in the visible range. The heating of irradiated fructose solution with non-irradiated alanine develops markedly more intensive browning than that of the heating of irradiated alanine solution with non-irradiated fructose. The products of fructose radiolysis are responsible for the acceleration of browning in the fructose-alanine system. (author)

  13. Topology of AspT, the Aspartate:Alanine Antiporter of Tetragenococcus halophilus, Determined by Site-Directed Fluorescence Labeling▿ †

    OpenAIRE

    Nanatani, Kei; Fujiki, Takashi; Kanou, Kazuhiko; Takeda-Shitaka, Mayuko; Umeyama, Hideaki; Ye, Liwen; WANG, XICHENG; Nakajima, Tasuku; Uchida, Takafumi; Maloney, Peter C.; Abe, Keietsu

    2007-01-01

    The gram-positive lactic acid bacterium Tetragenococcus halophilus catalyzes the decarboxylation of l-aspartate (Asp) with release of l-alanine (Ala) and CO2. The decarboxylation reaction consists of two steps: electrogenic exchange of Asp for Ala catalyzed by an aspartate:alanine antiporter (AspT) and intracellular decarboxylation of the transported Asp catalyzed by an l-aspartate-β-decarboxylase (AspD). AspT belongs to the newly classified aspartate:alanine exchanger family (transporter cla...

  14. Simplifying Likelihood Ratios

    OpenAIRE

    McGee, Steven

    2002-01-01

    Likelihood ratios are one of the best measures of diagnostic accuracy, although they are seldom used, because interpreting them requires a calculator to convert back and forth between “probability” and “odds” of disease. This article describes a simpler method of interpreting likelihood ratios, one that avoids calculators, nomograms, and conversions to “odds” of disease. Several examples illustrate how the clinician can use this method to refine diagnostic decisions at the bedside.

  15. Difference and ratio plots

    DEFF Research Database (Denmark)

    Svendsen, Anders Jørgen; Holmskov, U; Petersen, P H;

    1995-01-01

    hitherto unnoted differences between controls and patients with either rheumatoid arthritis or systemic lupus erythematosus. For this we use simple, but unconventional, graphic representations of the data, based on difference plots and ratio plots. Differences between patients with Burkitt's lymphoma...... and systemic lupus erythematosus from another previously published study (Macanovic, M. and Lachmann, P.J. (1979) Clin. Exp. Immunol. 38, 274) are also represented using ratio plots. Our observations indicate that analysis by regression analysis may often be misleading....

  16. Anaerobic metabolism in the N-limited green alga Selenastrum minutum. 3. Alanine is the product of anaerobic ammonium assimilation

    International Nuclear Information System (INIS)

    The authors have determined the flow of 15N into free amino acids of the N-limited green alga Selenastrum minutum (Naeg.) Collins after addition of 15NH4+ to aerobic or anaerobic cells. Under aerobic conditions, only a small proportion of the N assimilated was retained in the free amino acid pool. However, under anaerobic conditions almost all assimilated NH4+ accumulates in alanine. This is a unique feature of anaerobic NH4+ assimilation. The pathway of carbon flow to alanine results in the production of ATP and reductant which matches exactly the requirements of NH4+ assimilation. Alanine synthesis is therefore an excellent strategy to maintain energy and redox balance during anaerobic NH4+ assimilation

  17. Application of alanine dosimetry in dose assessment for ocular melanoma patients undergoing proton radiotherapy – preliminary results

    Directory of Open Access Journals (Sweden)

    Mierzwińska Gabriela

    2015-09-01

    Full Text Available Basing on alanine solid state/electron paramagnetic resonance (EPR dosimetry, a supplementary method of cumulatively recording the therapeutic dose received by ocular cancer patients undergoing fractionated proton radiotherapy is proposed. By applying alanine dosimetry during the delivery of consecutive fractions, the dose received within each fraction can be read out by EPR spectrometry and a final permanent cumulative record of the total dose delivered obtained. The dose response of the alanine detector was found to be practically independent on its position within the extended proton Bragg peak region. Dose measurements based on entrance dose recorded in proton beams individually formed for each patient are presented. The described method will be applied as a complementary Quality Assurance procedure for patients undergoing proton radiotherapy at the Institute of Nuclear Physics, Polish Academy of Sciences, Krakow, Poland (IFJ PAN.

  18. Crystal growth, structure and characterizations of a new semiorganic nonlinear optical material-β-Alanine zinc chloride

    International Nuclear Information System (INIS)

    The title compound, β-alanine zinc chloride-a new semiorganic nonlinear optical crystal was grown by slow evaporation technique. Single crystals of β-alanine zinc chloride have been subjected to X-ray diffraction analysis to determine the crystal structure. The powder X-ray diffractogram of the crystal has also been recorded. The amount of carbon, nitrogen and hydrogen in the crystals was also estimated. Fourier Transform Infrared and Raman spectral measurements have been carried out on the grown crystals in order to identify the functional groups. The presence of hydrogen and carbon in the β-alanine zinc chloride was confirmed by using proton and carbon nuclear magnetic resonance spectral analyses. The percentage of zinc in the crystal was determined by atomic absorption spectroscopy. Optical behavior such as ultraviolet-vis-near infrared transmittance spectrum and second harmonic generation has been investigated. The mechanical strength and thermal behavior of the grown crystal have been analyzed.

  19. Influence of temperature, L-alanine and phosphate buffer on the radiation susceptibility of Bacillus pumilus strain E601

    International Nuclear Information System (INIS)

    The Bacillus pumilus E601 strain has been examined for resistance to gamma and electron irradiation. Decimal reduction doses (D10 values), computed on the basis of recoverable organisms, have been found to depend on the dose rate of pulsed electrons in the range 1-1600krad per 35ns pulse. The highest dose rates in these ranges lead to higher D10 values than have been measured with the 60Co source (gamma irradiation). Treatment of heat-shocked B. pumilus spores with L-alanine in phosphate buffer resulted in a significant reduction in resistance towards both heat and radiation owing to the loss of spore properties. No response to alanine was observed in the absence of buffer. The sensitivity of alanine-germinated spores of B. pumilus (E601) to ionizing radiations was found to be identical with that of vegetative cells of this strain under the same conditions. (author)

  20. Influence of Temperature, L-Alanine and Phosphate Buffer on the Radiation Susceptibility of Bacillus Pumilus Strain E601

    International Nuclear Information System (INIS)

    The Bacillus pumilus E601 strain has been examined for resistance to gamma and electron irradiation. Decimal reduction doses (D10 values), computed on the basis of recoverable organisms, have been found to depend on the dose rate of pulsed electrons in the range 1 -1600 krad per 35 ns pulse. The highest dose rates in these ranges lead to higher D10 values than have been measured with the 60Co source (gamma irradiation). Treatment of heat-shocked B. pumilus spores with L-alanine in phosphate buffer resulted in a significant reduction in resistance towards both heat and radiation owing to the loss of spore properties. No response to alanine was observed in the absence of buffer. The sensitivity of alanine-germinated spores of B. pumilus (E601) to ionizing radiations was found to be identical with that of vegetative cells of this strain under the same conditions. (author)

  1. Resolution-enhancement of broadened spectra of the UV-light and thermal treated alanine free radicals

    International Nuclear Information System (INIS)

    Two methods for resolution-enhancing broadened spectra were analyzed. One method was used to treat ESR spectra of the γ-ray induced alanine free radicals and to study the effect when they are subjected to UV-light and heat. Spectral differences are obvious between these treatments. From a combined UV-light and heat treatment of these free radicals, some ESR lines disappear while five broad lines still remain. These spectral differences may clearly suggest the existence of two or more free radical species in γ-ray irradiated alanine that can be predicted at room temperature

  2. Characterization of the factors having an influence on the evolution of the EPR signal of irradiated alanine

    International Nuclear Information System (INIS)

    EPR/alanine dosimetry has been used by the LNHB (Laboratoire National Henri Becquerel) since many years for applied metrology. This technic is based on the measurement of the EPR signal of the free radicals induced in alanine by irradiation. The aim of this work is to characterize the factors having an influence on the evolution of the amplitude of the EPR signal of irradiated alanine to limit the uncertainties on the determination of the absorbed dose. The first step of this work has been the choice of the dosimeter. A bibliographic study completed by experiments on the response of alanine isomers to the dose and on its stability with time has lead us to choose L-α-alanine powder as dosimeter. The influence of the recording parameter of the spectrometer on the characteristics of the EPR spectrum has then been studied. This has enabled us to optimize the recording conditions of EPR spectra. As the angular anisotropy of the EPR signal limits the measurements reproducibility, an experimental protocol has been defined to solve this problem. The repeatability of the measurements has been enhanced by modifying the spectrometer and using an internal standard constituted of single crystals of CuSO4.5H2O. As the amplitude of the EPR signal is sensitive to the measurement temperature, a method of normalization of the results to 20 C has been determined. We have studied the influence of an irradiation parameter and of environmental parameters. We have shown that the EPR signal amplitude increases with irradiation temperature. The EPR signal amplitude and its evolution vary strongly with storage conditions (temperature and moisture) of the dosimeter before and after irradiation. The presence of moisture in alanine powder leads to a loss of signal amplitude. The dosimeters exposition to light also entails a loss of amplitude. Oxygen does not influence the EPR spectrum of alanine. We have noticed that the EPR signal amplitude of samples stored in absence of moisture increases

  3. Global Transcriptional and Physiological Responses of Saccharomyces cerevisiae to Ammonium, L-Alanine, or L-Glutamine Limitation

    DEFF Research Database (Denmark)

    Usaite, Renata; Patil, Kiran Raosaheb; Grotkjær, Thomas;

    2006-01-01

    The yeast Saccharomyces cerevisiae encounters a range of nitrogen sources at various concentrations in its environment. The impact of these two parameters on transcription and metabolism was studied by growing S. cerevisiae in chemostat cultures with L-glutamine, L-alanine, or L-ammonium in...... repression (NCR) may be responsible for this regulation. Ninety-one genes had transcript levels on both L-glutamine and ammonium that were decreased compared to those on L-alanine, independent of the concentration. The GATAAG element in these genes suggests two groups of NCR-responsive genes, those that...

  4. High-temperature Raman study of L-alanine, L-threonine and taurine crystals related to thermal decomposition

    Science.gov (United States)

    Cavaignac, A. L. O.; Lima, R. J. C.; Façanha Filho, P. F.; Moreno, A. J. D.; Freire, P. T. C.

    2016-03-01

    In this work high-temperature Raman spectra are used to compare temperature dependence of the lattice mode wavenumber of L-alanine, L-threonine and taurine crystals. Anharmonic effects observed are associated with intermolecular N-H· · ·O hydrogen bond that plays an important role in thermal decomposition process of these materials. Short and strong hydrogen bonds in L-alanine crystal were associated with anharmonic effects in lattice modes leading to low thermal stability compared to taurine crystals. Connection between thermal decomposition process and anharmonic effects is furnished for the first time.

  5. Effects of Beta-Alanine Supplementation on Brain Homocarnosine/Carnosine Signal and Cognitive Function: An Exploratory Study

    OpenAIRE

    Marina Yazigi Solis; Simon Cooper; Hobson, Ruth M; Artioli, Guilherme G.; Otaduy, Maria C.; Hamilton Roschel; Jacques Robertson; Daniel Martin; Vitor S Painelli; Harris, Roger C; Bruno Gualano; Craig Sale

    2015-01-01

    Objectives Two independent studies were conducted to examine the effects of 28 d of beta-alanine supplementation at 6.4 g d-1 on brain homocarnosine/carnosine signal in omnivores and vegetarians (Study 1) and on cognitive function before and after exercise in trained cyclists (Study 2). Methods In Study 1, seven healthy vegetarians (3 women and 4 men) and seven age- and sex-matched omnivores undertook a brain 1H-MRS exam at baseline and after beta-alanine supplementation. In study 2, nineteen...

  6. Densities and solubilities of Glycylglycine and Glycyl-L-Alanine in Aqueous Electrolyte Solutions

    DEFF Research Database (Denmark)

    Breil, Martin Peter; Mollerup, Jørgen; Rudolph, E. Susanne J.;

    2004-01-01

    is 1.74 and 4.78 mol/kg of water, respectively. The solubility of glycylglycine in salt solutions of NaCl, Na2SO4, and (NH4)(2)SO4 show a moderate salting-in effect. The solubility of glycyl-L-alanine show a minor or no salting-in effect at low salt concentrations and a moderate salting-out effect...... at higher salt concentrations in NaCl and Na2SO4, and in (NH4)(2)SO4 the solubility is almost constant. The densities of the solutions have been determined experimentally, and the volume expansions by dissolving salt and dipeptide in water have been calculated. (C) 2003 Elsevier B.V. All rights reserved....

  7. Crystallization and preliminary X-ray study of alanine dehydrogenase from Bacillus pseudofirmus OF4

    Science.gov (United States)

    Wen, Jinjin; Li, Zhenzhen; He, Guangzheng; Xu, Shujing; Zhao, Baohua; Zhu, Xianming; Dong, Hui; Ju, Jiansong

    2013-01-01

    Alanine dehydrogenase (OF4Ald) from the alkaliphilic Bacillus pseudofirmus OF4 was expressed and purified with a His6 tag in a form suitable for X-ray crystallographic analysis. Crystals were grown by the hanging-drop vapour-diffusion method at 289 K using a solution consisting of 0.1 M Tris–HCl pH 8.0, 0.2 M LiSO4, 22%(w/v) PEG 3350. X-ray diffraction data were collected to 2.8 Å resolution. The crystal belonged to the triclinic space group P1, with unit-cell parameters a = 88.04, b = 105.59, c = 120.53 Å, α = 88.37, β = 78.77, γ = 82.65°. PMID:24192355

  8. Ste20-related proline/alanine-rich kinase: A novel regulator of intestinal inflammation

    Institute of Scientific and Technical Information of China (English)

    Yutao Yan; Didier Merlin

    2008-01-01

    Recently, inflammatory bowel disease (IBD) has been the subject of considerable research, with increasing attention being paid to the loss of intestinal epithelial cell barrier function as a mechanism of pathogenesis. Ste20-related proline/alanine-rich kinase (SPAK) is involved in regulating barrier function. SPAK is known to interact with inflammation-related kinases (such as p38, JNK, NKCC1, PKCθ, WNK and MLCK), and with transcription factor AP-1, resulting in diverse biological phenomena, including cell differentiation, cell transformation and proliferation, cytoskeleton rearrangement, and regulation of chloride transport. This review examines the involvement of Ste20-like kinases and downstream mitogen-activated protein kinases (MAPKs) pathways in the pathogenesis and control of intestinal inflammation. The primary focus will be on the molecular features of intestinal inflammation, with an emphasis on the interaction between SPAK and other molecules, and the effect of these interactions on homeostatic maintenance, cell volume regulation and increased cell permeability in intestinal inflammation.

  9. Quantification of neurotoxin BMAA (β-N-methylamino-L-alanine) in seafood from Swedish markets

    Science.gov (United States)

    Jiang, Liying; Kiselova, Nadezda; Rosén, Johan; Ilag, Leopold L.

    2014-11-01

    The neurotoxin β-N-methylamino-L-alanine (BMAA) produced naturally by cyanobacteria, diatoms and dinoflagellates can be transferred and accumulated up the food chain, and may be a risk factor for neurodegenerative diseases. This study provides the first systematic screening of BMAA exposure of a large population through the consumption of seafood sold in metropolitan markets. BMAA was distinguished from known isomers by liquid chromatography tandem mass spectrometry after acidic hydrolysis and derivatization. Using deuterium-labeled internal standard, BMAA was quantified as 0.01-0.90 μg/g wet weight of tissues in blue mussel, oyster, shrimp, plaice, char and herring, but was undetectable (content of BMAA detected is relevant for intake calculations, the data presented may be used for a first estimation of BMAA exposure through seafood from Swedish markets, and to refine the design of future toxicological experiments and assessments.

  10. Formation Equilibria of Ternary Metal Complexes with Citric Acid and Glutamine (Alanine) in Aqueous Solution

    Institute of Scientific and Technical Information of China (English)

    王进平; 牛春吉; 杨魁跃; 倪嘉缵

    2004-01-01

    The species and their formation constants in the ternary systems were obtained by the Scogs2 software from potentiometric titration data. The Comics software was used to calculate the distribution of species in the ternary systems. MLXH, MLXH2 and MLXH3 are the common species in these systems. The coordination behaviors of the rare earths are very similar and their stability is closely matched. The ternary rare earth complexes are more stable than the corresponding ternary complexes of calcium. The ternary zinc complex with glutamine as the secondary ligand is more stable than the corresponding complexes of rare earths, but the ternary complex with alanine as the secondary ligand shows an inverse trend. The distributions of species in the ternary systems vary with pH changing. A prediction can be made that exogenous rare earths can affect the species of Ca and Zn in human body.

  11. A Thermochemical Study of the Reaction of Lanthanum Nitrate with Alanine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The standard molar reaction enthalpy of the solid-solid coordination reaction La(NO3)3 ·6H2O (s) +4Ala(s) (Ala is Alanine)=La(NO3)3 · (Ala)4 · H2O(s) + 5H2O(1) was studied byusing classical solution calorimetry. The molar dissolution enthalpies of the reactants and theproduct of the solid-solid coordination reaction in 2 mol/L HCl were measured by using anisoperibol calorimeter. From the results and other auxiliary quantities, the standard molar formation enthalpy of [La (NO3)3 · (Ala)4 · H2O, s, 298. 15 K] has been determined to be△fHm [La(NO3)3 · (Ala)4 · H2O, s, 298. 15 K]=-3 864. 248 kJ/mol.

  12. Excitatory amino acid b-N-methylamino-L-alanine is a putative environmental neurotoxin

    Directory of Open Access Journals (Sweden)

    VLADIMIR NEDELJKOV

    2011-04-01

    Full Text Available The amino acid b-N-methylamino-L-alanine (L-BMAA has been associated with the amyotrophic lateral sclerosis/parkinsonism-dementia complex in three distinct western Pacific populations. The putative neurotoxin is produced by cyanobacteria, which live symbiotically in the roots of cycad trees. L-BMAA was thought to be a threat only to those few populations whose diet and medicines rely heavily on cycad seeds. However, the recent discovery that cyanobacteria from diverse terrestrial, freshwater, and saltwater ecosystems around the world produce the toxin requires a reassessment of whether it poses a larger health threat. Therefore, it is proposed that monitoring L-BMAA levels in cyanobacteria-contaminated water supplies might be prudent.

  13. Growth and characterization of organometallic L-alanine cadmium chloride single crystal by slow evaporation technique

    Energy Technology Data Exchange (ETDEWEB)

    Bright, K.C., E-mail: brightmcc@yahoo.co.i [Department of Physics, Malankara Catholic College, Mariyagiri 629153, Tamil Nadu (India); Freeda, T.H. [Physics Research Center, S.T. Hindu College, Nagercoil 629002, Tamil Nadu (India)

    2010-09-15

    Single crystals of L-alanine cadmium chloride (LACC), an organometallic nonlinear optical material, have been grown by the slow evaporation technique. The grown crystals were subjected to various characterization techniques, such as single crystal and powder XRD, FTIR, UV-vis and TGA-DTA. The mechanical properties of the crystals show that this material belongs to the category of hard materials. Second harmonic generation was confirmed by the Kurtz and Perry powder technique. Electrical parameters, such as dielectric constant, dielectric loss, ac and dc conductivity and their corresponding activation energies have been studied. The low dielectric constant and dielectric loss suggest that this material is a good candidate for micro-electronic applications.

  14. Optical properties of europium compounds with L- and DL-{alpha}-alanine-hydroxamic acids

    Energy Technology Data Exchange (ETDEWEB)

    Legendziewicz, J.; Gawryszewska, P. [Faculty of Chemistry, University of Wroclaw (Poland); Galdecka, E. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Wroclaw (Poland); Galdecki, Z. [Institute of General and Ecological Chemistry, Technical University of Lodz (Poland)

    1996-12-31

    Two europium complexes with L- and DL-{alpha}-alanine-hydroxamic acids were synthesized. To our knowledge they are the first examples of X-ray and spectral data lanthanide single crystals with hydroxamic acid derivatives. Both compounds consists of dimers in their structures, formed by two OH bridging groups of amino-hydroxamic acid molecules. Besides, two metal ions are chelated by CO and OH groups, forming five-membered groups. In the complex with L-ligand, different than DL-one, two additional perchloric acid molecules are included in crystal cavities and form hydrogen bondings with nitrogen and oxygen atoms of the ligand. Absorption, emission and excitation spectra were measured and analysed at room and low temperatures. Structural effect of ligand chirality was found and its spectroscopic consequences are reported. The effect of the dimeric structure on spectroscopic properties is discussed. (author) 30 refs, 5 figs, 2 tabs

  15. Optical properties of the radical anion derived from {alpha}-alanine by deamination

    Energy Technology Data Exchange (ETDEWEB)

    Zagorski, Z.P.; Przybytniak, G.K. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    1997-12-31

    The free radical anion CH{sub 3}CHCOO derived during high energy irradiation from {alpha}-alanine by deamination has been investigated until now by EPR, in irradiated single crystals, for basic research or in completely randomized polycrystalline material for {gamma}-dosimetric purposes. It has been found by spectrophotometry of irradiated single crystals that the free radical absorbs light at {lambda}{sub max}=350 nm. The same radical anion is observed by pulse radiolysis of {alpha}-chloropropionic or propionic anion in aqueous solutions by Cl resp. {alpha}-H abstraction.Basic and applied aspects of the identity of the radical anion obtained in different ways are discussed, as well as consequences for dosimetric techniques. (author). 11 refs, 4 figs.

  16. Alanine in high-dose dosimetry: spectrophotometric and electrochemical readout procedures compared with ESR

    Energy Technology Data Exchange (ETDEWEB)

    Van Laere, K.; Buysse, J.; Berkvens, P. (Ghent Rijksuniversiteit (Belgium). Lab. voor Kernfysica)

    1989-01-01

    The ESR readout of radical concentrations produced upon irradiation of {alpha}-alanine is compared and related to other physico-chemical detection methods. Dissolution of the free radicals in an acid ferrous sulphate solution leads to an indirect oxidation of ferrous ions. After complex formation with the dye xylenol orange optical absorption measurements can be made within a dose range from 0.03 to 12 kGy. The yield of ammonia, produced upon dissolution in a basic aqueous solution, provides spectrophotometric evaluations after complex formation with a mercury iodide containing reagent for the dose range 5 kGy to 1 MGy. A practical new routine dosimeter for applications in the range 300 Gy to at least 1 MGy, by means of an ion-selective ammonia electrode, is proposed. (author).

  17. Assessment of an alanine EPR dosimetry technique with enhanced precision and accuracy

    CERN Document Server

    Hayes, R B; Wieser, A; Romanyukha, A A; Hardy, B L; Barrus, J K

    2000-01-01

    Dose reconstruction in the course of a series of blind tests demonstrated that an accuracy of 10 mGy for low doses and 1% for high doses can be achieved using EPR spectroscopy. This was accomplished using a combination of methodologies including polynomial filtration of the EPR spectrum, dosimeter rotation during scanning, use of an EPR standard fixed into the resonator and subtraction of all nonradiogenic signals. Doses were reconstructed over the range of 0.01-1000 Gy using this compound spectral EPR analysis. This EPR technique, being equally applicable to fractionated doses (such as those delivered during multiple radiotherapy treatments), was verified to exhibit dose reciprocity. Irradiated alanine dosimeters which were stored exhibited compound spectral EPR signal fading of ca 3% over 9 months. All error estimates given in this paper are given at the 1 standard deviation level and unless otherwise specified do not account for uncertainties in source calibration.

  18. Effect of mammals’ excretory function on aspartate aminotransferase activity in Glechoma hederacea leaves in conditions of Cd pollution

    Directory of Open Access Journals (Sweden)

    O. M. Vasilyuk

    2014-07-01

    Full Text Available The paper includes analysis of research of Cd impact on the activity of the enzyme of aspartate aminotransferase (AST nitrogen metabolism and the content of water-soluble protein fraction (albumin in Glechoma hederacea L. leaves, which dominated in the research area (in natural floodplain oak forest with Stellaria holostea L.. Cd was introduced in the form of salts of Cd(NO32 in the range of concentrations of: 0.25, 1.25, 2.5 g/m2, equivalent to the inclusion of Cd in 1, 5, 10 doses of MAC. Increase (P < 0.05 in the activity of AST 2.6–3.0 times (with adding Cd salts at a dose of 1 and 5 МAС and albumin content by 37% (with adding Cd salts at a dose of 10 МAС compared to control (the area without Cd pollution and excretory activity of mammals was shown. Using of excreta of some representatives of mammals (for example, Capreolus capreolus L. contributed to reduction of Cd toxic effects and restoring of the functional metabolic activity of AST by 23% (with Cd 1 МAС and by 34% (Cd 5 МAС. It is the evidence of protective function of mammals and their normalization effect at the above concentrations of Cd. Whereas the adding of Cd salts at a dose of 10 МAС led to 3 times’ inhibition of AST activity, the toxic effect of metal by excretory function of mammals was not reduced. Observations revealed the albumin content normalization by 22% in the presence of Cd 1MAC respectively (with the introduction of C. capreolus excreta and to the control level (the area without Cd pollution and excretory activity of mammals with the excreta of Sus scrofa L. in the setting of Cd 10 MAC. It proves the need to use the different mammal species for integrated and comprehensive normalization of ecosystems under conditions of uncontrolled anthropogenic pollution.

  19. Mechanism of Substrate Recognition And PLP-Induced Conformational Changes in II-Diaminopimelate Aminotransferase From Arabidopsis Thaliana

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    Watanabe, N.; Clay, M.D.; Belkum, M.J.van; Cherney, M.M.; Vederas, J.C.; James, M.N.G.

    2009-05-26

    LL-Diaminopimelate aminotransferase (LL-DAP-AT), a pyridoxal phosphate (PLP)-dependent enzyme in the lysine biosynthetic pathways of plants and Chlamydia, is a potential target for the development of herbicides or antibiotics. This homodimeric enzyme converts L-tetrahydrodipicolinic acid (THDP) directly to LL-DAP using L-glutamate as the source of the amino group. Earlier, we described the 3D structures of native and malate-bound LL-DAP-AT from Arabidopsis thaliana (AtDAP-AT). Seven additional crystal structures of AtDAP-AT and its variants are reported here as part of an investigation into the mechanism of substrate recognition and catalysis. Two structures are of AtDAP-AT with reduced external aldimine analogues: N-(5'-phosphopyridoxyl)-L-glutamate (PLP-Glu) and N-(5'-phosphopyridoxyl)- LL-Diaminopimelate (PLP-DAP) bound in the active site. Surprisingly, they reveal that both L-glutamate and LL-DAP are recognized in a very similar fashion by the same sets of amino acid residues; both molecules adopt twisted V-shaped conformations. With both substrates, the {alpha}-carboxylates are bound in a salt bridge with Arg404, whereas the distal carboxylates are recognized via hydrogen bonds to the well-conserved side chains of Tyr37, Tyr125 and Lys129. The distal C{sup {var_epsilon}} amino group of LL-DAP is specifically recognized by several non-covalent interactions with residues from the other subunit (Asn309*, Tyr94*, Gly95*, and Glu97* (Amino acid designators followed by an asterisk (*) indicate that the residues originate in the other subunit of the dimer)) and by three bound water molecules. Two catalytically inactive variants of AtDAP-AT were created via site-directed mutagenesis of the active site lysine (K270N and K270Q). The structures of these variants permitted the observation of the unreduced external aldimines of PLP with L-glutamate and with LL-DAP in the active site, and revealed differences in the torsion angle about the PLP-substrate bond

  20. Chiral selectivity of amino acid adsorption on chiral surfaces—The case of alanine on Pt

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    Franke, J.-H.; Kosov, D. S. [Department of Physics, Campus Plaine - CP 231, Université Libre de Bruxelles, 1050 Brussels (Belgium)

    2015-02-07

    We study the binding pattern of the amino acid alanine on the naturally chiral Pt surfaces Pt(531), Pt(321), and Pt(643). These surfaces are all vicinal to the (111) direction but have different local environments of their kink sites and are thus a model for realistic roughened Pt surfaces. Alanine has only a single methyl group attached to its chiral center, which makes the number of possible binding conformations computationally tractable. Additionally, only the amine and carboxyl group are expected to interact strongly with the Pt substrate. On Pt(531), we study the molecule in its pristine as well as its deprotonated form and find that the deprotonated one is more stable by 0.47 eV. Therefore, we study the molecule in its deprotonated form on Pt(321) and Pt(643). As expected, the oxygen and nitrogen atoms of the deprotonated molecule provide a local binding “tripod” and the most stable adsorption configurations optimize the interaction of this “tripod” with undercoordinated surface atoms. However, the interaction of the methyl group plays an important role: it induces significant chiral selectivity of about 60 meV on all surfaces. Hereby, the L-enantiomer adsorbs preferentially to the Pt(321){sup S} and Pt(643){sup S} surfaces, while the D-enantiomer is more stable on Pt(531){sup S}. The binding energies increase with increasing surface density of kink sites, i.e., they are largest for Pt(531){sup S} and smallest for Pt(643){sup S}.