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Sample records for enzimas gsts sults

  1. Identification and characterization of two novel cytosolic sulfotransferases, SULT1 ST7 and SULT1 ST8, from zebrafish

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    Liu, T.-A. [Department of Pharmacology, College of Pharmacy, University of Toledo, Toledo, OH 43606 (United States); Department of Biological Science and Technology, College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan (China); Bhuiyan, Shakhawat [Division of Arts and Sciences, Jarvis Christian College, Hawkins, TX 75765 (United States); Snow, Rhodora [School of Mathematics and Science, J. Sargeant Reynolds Community College, Richmond, VA 23285 (United States); Yasuda, Shin; Yasuda, Tomoko [Department of Pharmacology, College of Pharmacy, University of Toledo, Toledo, OH 43606 (United States); Yang, Y.-S. [Department of Biological Science and Technology, College of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan (China); Williams, Frederick E.; Liu, M.-Y.; Suiko, Masahito [Department of Pharmacology, College of Pharmacy, University of Toledo, Toledo, OH 43606 (United States); Carter, Glendora [School of Mathematics and Science, J. Sargeant Reynolds Community College, Richmond, VA 23285 (United States); Liu, M.-C. [Department of Pharmacology, College of Pharmacy, University of Toledo, Toledo, OH 43606 (United States)], E-mail: ming.liu@utoledo.edu

    2008-08-29

    Cytosolic sulfotransferases (SULTs) constitute a family of Phase II detoxification enzymes that are involved in the protection against potentially harmful xenobiotics as well as the regulation and homeostasis of endogenous compounds. Compared with humans and rodents, the zebrafish serves as an excellent model for studying the role of SULTs in the detoxification of environmental pollutants including environmental estrogens. By searching the expressed sequence tag database, two zebrafish cDNAs encoding putative SULTs were identified. Sequence analysis indicated that these two putative zebrafish SULTs belong to the SULT1 gene family. The recombinant form of these two novel zebrafish SULTs, designated SULT1 ST7 and SULT1 ST8, were expressed using the pGEX-2TK glutathione S-transferase (GST) gene fusion system and purified from transformed BL21 (DE3) cells. Purified GST-fusion protein form of SULT1 ST7 and SULT1 ST8 exhibited strong sulfating activities toward environmental estrogens, particularly hydroxylated polychlorinated biphenyls (PCBs), among various endogenous and xenobiotic compounds tested as substrates. pH-dependence experiments showed that SULT1 ST7 and SULT1 ST8 displayed pH optima at 6.5 and 8.0, respectively. Kinetic parameters of the two enzymes in catalyzing the sulfation of catechin and chlorogenic acid as well as 3-chloro-4-biphenylol were determined. Developmental expression experiments revealed distinct patterns of expression of SULT1 ST7 and SULT1 ST8 during embryonic development and throughout the larval stage onto maturity.

  2. Crystal structures of human sulfotransferases SULT1B1 and SULT1C1 complexed with the cofactor product adenosine-3'- 5'-diphosphate (PAP)

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    Dombrovski, Luidmila; Dong, Aiping; Bochkarev, Alexey; Plotnikov, Alexander N. (Toronto)

    2008-09-17

    Cytosolic sulfotransferases (SULTs), often referred as Phase II enzymes of chemical defense, are a superfamily of enzymes that catalyze the transfer of a sulfonate group from 3{prime}-phosphoadenosine 5{prime}-phosphosulfate (PAPS) to an acceptor group of substrates. This reaction modulates the activities of a large array of small endogenous and foreign chemicals including drugs, toxic compounds, steroid hormones, and neurotransmitters. In some cases, however, SULTs activate certain food and environmental compounds to mutagenenic and carcinogenic metabolites. Twelve human SULTs have been identified, which are partitioned into three families: SULT1, SULT2 and SULT4. The SULT1 family is further divided in four subfamilies, A, B, C, and E, and comprises eight members (1A1, 1A2, 1A3, 1B1, 1C1, 1C2, 1C3, and 1E1). Despite sequence and structural similarity among the SULTs, the family and subfamily members appear to have different biological function. SULT1 family shows substrate-binding specificity for simple phenols, estradiol, and thyroid hormones, as well as environmental xenobiotics and drugs. Human SULT1B1 is expressed in liver, colon, small intestine, and blood leukocytes, and shows substrate-binding specificity to thyroid hormones and benzylic alcohols. Human SULT1C1 is expressed in the adult stomach, kidney, and thyroid, as well as in fetal kidney and liver. SULT1C1 catalyzes the sulfonation of p-nitrophenol and N-hydroxy-2-acetylaminofluorene in vitro. However, the in vivo function of the enzyme remains unknown. We intend to solve the structures for all of the SULTs for which structural information is not yet available, and compare the structural and functional features of the entire SULT superfamily. Here we report the structures of two members of SULT1 family, SULT1B1 and SULT1C1, both in complex with the product of the PAPS cofactor, adenosine-3{prime}-5{prime}-diphosphate (PAP).

  3. Sulfation of fulvestrant by human liver cytosols and recombinant SULT1A1 and SULT1E1

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    Edavana VK

    2011-11-01

    Full Text Available Vineetha Koroth Edavana1, Xinfeng Yu1, Ishwori B Dhakal1, Suzanne Williams1, Baitang Ning2, Ian T Cook3, David Caldwell1, Charles N Falany3, Susan Kadlubar11Division of Medical Genetics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA; 2Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR, USA; 3Department of Pharmacology, University of Alabama, Birmingham, AL, USAAbstract: Fulvestrant (Faslodex™ is a pure antiestrogen that is approved to treat hormone receptor-positive metastatic breast cancer in postmenopausal women. Previous studies have demonstrated that fulvestrant metabolism in humans involves cytochromes P450 and UDP-glucuronosyltransferases (UGTs. To date, fulvestrant sulfation has not been characterized. This study examined fulvestrant sulfation with nine recombinant sulfotransferases and found that only SULT1A1 and SULT1E1 displayed catalytic activity toward this substrate, with Km of 4.2 ± 0.99 and 0.2 ± 0.16 µM, respectively. In vitro assays of 104 human liver cytosols revealed marked individual variability that was highly correlated with β-naphthol sulfation (SULT1A1 diagnostic substrate; r = 0.98, P < 0.0001, but not with 17ß-estradiol sulfation (SULT1E1 diagnostic substrate; r = 0.16, P = 0.10. Fulvestrant sulfation was correlated with both SULT1A1*1/2 genotype (P value = 0.023 and copy number (P < 0.0001. These studies suggest that factors influencing SULT1A1/1E1 tissue expression and/or enzymatic activity could influence the efficacy of fulvestrant therapy.Keywords: fulvestrant, sulfotransferase, genotype, copy number

  4. SULT1A1 copy number variation: ethnic distribution analysis in an Indian population.

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    Almal, Suhani; Padh, Harish

    2017-11-01

    Cytosolic sulfotransferases (SULTs) are phase II detoxification enzymes involved in metabolism of numerous xenobiotics, drugs and endogenous compounds. Interindividual variation in sulfonation capacity is important for determining an individual's response to xenobiotics. SNPs in SULTs, mainly SULT1A1 have been associated with cancer risk and also with response to therapeutic agents. Copy number variation (CNVs) in SULT1A1 is found to be correlated with altered enzyme activity. This short report primarily focuses on CNV in SULT1A1 and its distribution among different ethnic populations around the globe. Frequency distribution of SULT1A1 copy number (CN) in 157 healthy Indian individuals was assessed using florescent-based quantitative PCR assay. A range of 1 to >4 copies, with a frequency of SULT1A1 CN =2 (64.9%) the highest, was observed in our (Indian) population. Upon comparative analysis of frequency distribution of SULT1A1 CN among diverse population groups, a statistically significant difference was observed between Indians (our data) and African-American (AA) (p = 0.0001) and South African (Tswana) (p populations. Distribution of CNV in the Indian population was found to be similar to that in European-derived populations of American and Japanese. CNV of SULT1A1 varies significantly among world populations and may be one of the determinants of health and diseases.

  5. Caractérisation biochimique et fonctionnelle de glutathion-S-transferases (GSTs) chez Phanerochaete chrysosporium

    OpenAIRE

    Anak Ngadin , Andrew

    2011-01-01

    Phanerochaete chrysosporium is a ligninolytic fungus widely studied because of its capacities to degrade wood and xenobiotics through an extracellular enzymatic system. Its genome has been sequenced and has provided researchers with a complete inventory of the predicted proteins produced by this organism. This has allowed the description of many protein superfamilies. Among them, Glutathione S-transferases (GSTs) constitute a complex and widespread superfamily classified as enzymes of seconda...

  6. Kuu plaat : Märt Sults "Kõigest koolipapa...". Plaadid kauplusest Lasering

    Index Scriptorium Estoniae

    2005-01-01

    Heliplaatidest : Märt Sults "Kõigest koolipapa...", Madonna "Confessions on a Dance Floor", Tõnis Mägi "Vestlus Hermanniga", Rammstein "Rosenrot", a-ha "Analogue", Darkness "One Way Ticket to Hell...And Back"

  7. CYP1A1, CYP1A2, SULT1A1 AND SULT1E1 ALLELIC POLYMORPHISM IN CASE OF GENITAL ENDOMETRIOSIS

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    Konstantin Sergeevich Kublinskiy

    2016-02-01

    Up-to-date molecular and genetic analyses reveal that women predisposed to genital endometriosis possess Allele G and Genotypes AG and GG of the polymorphic option A-4889G of the CYP1A1 gene and Allele A and Genotypes CA and AA of the polymorphic option C-734A of the CYP1A2 gene. The polymorphism of the promoter regions of the SULT1A1 (G-638A and SULT1E1 (C-174T genes is not associated with genital endometriosis in women.

  8. Cigarette smoke toxicants as substrates and inhibitors for human cytosolic SULTs

    International Nuclear Information System (INIS)

    Yasuda, Shin; Idell, Steven; Fu Jian; Carter, Glendora; Snow, Rhodora; Liu, M.-C.

    2007-01-01

    The current study was designed to examine the role of sulfation in the metabolism of cigarette smoke toxicants and clarify whether these toxicants, by serving as substrates for the cytosolic sulfotransferases (SULTs), may interfere with the sulfation of key endogenous compounds. By metabolic labeling, [ 35 S]sulfated species were found to be generated and released into the media of HepG2 human hepatoma cells and primary human lung endothelial cells labeled with [ 35 S]sulfate in the presence of cigarette smoke extract (CSE). Concomitantly, several [ 35 S]sulfated metabolites observed in the medium in the absence of CSE either decreased or disappeared. Eleven previously prepared human cytosolic SULTs were tested for sulfating activity with CSE and known cigarette smoke toxicants as substrates. Activity data revealed SULT1A1, SULT1A2, SULT1A3, and SULT1C2 as major enzymes responsible for their sulfation. To examine their inhibitory effects on the sulfation of 17β-estradiol by SULT1A1, enzymatic assays were performed in the presence of three representative toxicant compounds, namely N-hydroxy-4-aminobiphenyl (N-OH-4-ABP), 4-aminobiphenyl (4-ABP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). IC 50 values determined for the sulfation of 17β-estradiol by SULT1A1 were 11.8 μM, 28.2 μM, and 500 μM, respectively, for N-OH-4-ABP, 4-ABP and PhIP. Kinetic analyses indicated that the mechanism underlying the inhibition of 17β-estradiol sulfation by these cigarette smoke toxicants is of a mixed competitive-noncompetitive type. Metabolic labeling experiments clearly showed inhibition of the production of [ 35 S]sulfated 17β-estradiol by N-OH-4-ABP in a concentration-dependent manner in HepG2 cells. Taken together, these results suggest that sulfation plays a significant role in the metabolism of cigarette smoke compounds. By serving as substrates for SULTs, cigarette smoke toxicants may interfere with the metabolism of 17β-estradiol and other endogenous

  9. Hydroxysteroid sulfotransferase SULT2B1b promotes hepatocellular carcinoma cells proliferation in vitro and in vivo.

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    Xiaoming Yang

    Full Text Available Hydroxysteroid sulfotransferase 2B1b (SULT2B1b is highly selective for the addition of sulfate groups to 3β-hydroxysteroids. Although previous reports have suggested that SULT2B1b is correlated with cell proliferation of hepatocytes, the relationship between SULT2B1b and the malignant phenotype of hepatocarcinoma cells was not clear. In the present study, we found that SULT2B1 was comparatively higher in the human hepatocarcinoma tumorous tissues than their adjacent tissues. Besides, SULT2B1b overexpression promoted the growth of the mouse hepatocarcinoma cell line Hepa1-6, while Lentivirus-mediated SULT2B1b interference inhibited growth as assessed by the CCK-8 assay. Likewise, inhibition of SULT2B1b expression induced cell-cycle arrest and apoptosis in Hepa1-6 cells by upregulating the expression of FAS, downregulating the expression of cyclinB1, BCL2 and MYC in vitro and in vivo at both the transcript and protein levels. Knock-down of SULT2B1b expression significantly suppressed tumor growth in nude mouse xenografts. Moreover, proliferation rates and SULT2B1b expression were highly correlated in the human hepatocarcinoma cell lines Huh-7, Hep3B, SMMC-7721 and BEL-7402 cells. Knock-down of SULT2B1b inhibited cell growth and cyclinB1 levels in human hepatocarcinoma cells and suppressed xenograft growth in vivo. In conclusion, SULT2B1b expression promotes proliferation of hepatocellular carcinoma cells in vitro and in vivo, which may contribute to the progression of HCC.

  10. Dopamine-induced SULT1A3/4 promotes EMT and cancer stemness in hepatocellular carcinoma.

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    Zou, Juan; Li, Hong; Huang, Qianling; Liu, Xiaomin; Qi, Xiaoxiao; Wang, Ying; Lu, Linlin; Liu, Zhongqiu

    2017-10-01

    Hepatocellular carcinoma has the second highest incidence rate among malignant cancers in China. Hepatocellular carcinoma development is complex because of the metabolism disequilibrium involving SULT1A3/4, a predominant sulfotransferase that metabolizes sulfonic xenobiotics and endogenous catecholamines. However, the correlation between SULT1A3/4 and hepatocellular carcinoma progression is unclear. By utilizing immunofluorescence and immunohistochemical analysis, we found that in nine hepatocellular carcinoma clinical specimens, SULT1A3/4 was abundantly expressed in tumor tissues compared to that in the adjacent tissues. Moreover, liver cancer cells (HepG2, MHCC97-L, and MHCC97-H) had higher basal expression of SULT1A3/4 than immortalized liver cells (L02 and Chang liver). Ultra-high-pressure liquid chromatography-tandem mass spectrometry assay results further revealed that the concentration of dopamine (a substrate of SULT1A3/4) was negatively correlated with SULT1A3/4 protein expression. As a transcriptional regulator of SULT1A3/4 in turn, dopamine was used to induce SULT1A3/4 in vitro. Interestingly, dopamine significantly induced SULT1A3/4 expression in liver cancer HepG2 cells, while decreased that in L02 cells. More importantly, the expression levels of epithelial-mesenchymal transition biomarkers (N-cadherin and vimentin) and cell stemness biomarkers (nanog, sox2, and oct3/4) considerably increased in HepG2 with dopamine-induced SULT1A3/4, whereas in L02, epithelial-mesenchymal transition and cancer stem cell-associated proteins were contrarily decreased. Furthermore, invasion and migration assays further revealed that dopamine-induced SULT1A3/4 dramatically stimulated the metastatic capacity of HepG2 cells. Our results implied that SULT1A3/4 exhibited bidirectional effect on tumor and normal hepatocytes and may thus provide a novel strategy for hepatocellular carcinoma clinical targeting. In addition, SULT1A3/4 re-expression could serve as a biomarker for

  11. Targeting Sulfotransferase (SULT) 2B1b as a regulator of Cholesterol Metabolism in Prostate Cancer

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    2016-10-01

    associated with de novo androgen synthesis will be addressed based on the hypothesis that SULT2B1b promotes PCa proliferation by impacting the...evaluation of sulfonation activity on other sterols using in vitro assays. Seven thousand (7,000) compounds were screened after computational...stim- ulation, and previous studies have demonstrated that cholesterol canbeused as a precursor for androgen synthesis (6, 26). Thus, the impact of

  12. Liver X receptor alpha mediated genistein induction of human dehydroepiandrosterone sulfotransferase (hSULT2A1) in Hep G2 cells

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    Chen, Yue; Zhang, Shunfen [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States); Zhou, Tianyan [Department of Pharmaceutics, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 100083 (China); Huang, Chaoqun; McLaughlin, Alicia [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States); Chen, Guangping, E-mail: guangping.chen@okstate.edu [Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078 (United States)

    2013-04-15

    Cytosolic sulfotransferases are one of the major families of phase II drug metabolizing enzymes. Sulfotransferase-catalyzed sulfonation regulates hormone activities, metabolizes drugs, detoxifies xenobiotics, and bioactivates carcinogens. Human dehydroepiandrosterone sulfotransferase (hSULT2A1) plays important biological roles by sulfating endogenous hydroxysteroids and exogenous xenobiotics. Genistein, mainly existing in soy food products, is a naturally occurring phytoestrogen with both chemopreventive and chemotherapeutic potential. Our previous studies have shown that genistein significantly induces hSULT2A1 in Hep G2 and Caco-2 cells. In this study, we investigated the roles of liver X receptor (LXRα) in the genistein induction of hSULT2A1. LXRs have been shown to induce expression of mouse Sult2a9 and hSULT2A1 gene. Our results demonstrate that LXRα mediates the genistein induction of hSULT2A1, supported by Western blot analysis results, hSULT2A1 promoter driven luciferase reporter gene assay results, and mRNA interference results. Chromatin immunoprecipitation (ChIP) assay results demonstrate that genistein increase the recruitment of hLXRα binding to the hSULT2A1 promoter. These results suggest that hLXRα plays an important role in the hSULT2A1 gene regulation. The biological functions of phytoestrogens may partially relate to their induction activity toward hydroxysteroid SULT. - Highlights: ► Liver X receptor α mediated genistein induction of hSULT2A1 in Hep G2 cells. ► LXRα and RXRα dimerization further activated this induction. ► Western blot results agreed well with luciferase reporter gene assay results. ► LXRs gene silencing significantly decreased hSULT2A1 expression. ► ChIP analysis suggested that genistein enhances hLXRα binding to the hSULT2A1 promoter.

  13. O ENSINO DE ENZIMAS: UMA ABORDAGEM EXPERIMENTAL DE BAIXO CUSTO

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    William de Azevedo Pinheiro

    2011-07-01

    Full Text Available Este trabalho descreve uma atividade prática de Bioquímica, a qual expõe alternativasdidáticas que visam facilitar processo ensino/aprendizado dos conceitos associados ao temaEnzimas. O estudo foi realizado em escolas de Ensino Médio da rede pública Estadual naregião Noroeste Fluminense do Estado do Rio de Janeiro. O trabalho consiste nodesenvolvimento de uma atividade prática, sobre Enzimas, utilizando materiais alternativose/ou de baixo custo. O trabalho objetiva, ainda, ser um agente de incentivo ao trabalho emequipes interdisciplinares dentro de uma visão holística multidisciplinar da construção doconhecimento, possível de ser explorada nas Ciências Biológicas e Exatas.

  14. Inmovilización de enzimas en materiales mesoporosos ordenados

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    Serra, Elías M.

    2011-01-01

    En este trabajo se ha pretendido arrojar algo de luz sobre algunos aspectos que afectan a la inmovilización de enzimas en Materiales Mesoporosos Ordenados. La mayor parte del esfuerzo se ha centrado en la inmovilización de la lipasa, sin perder de vista la extensión de las técnicas más exitosas a otras enzimas de interés. En primer lugar se ha establecido la influencia de parámetros texturales y/o químicos de los MMO sobre la inmovilización, mostrando como tanto el tamaño como la forma de ...

  15. Targeting Sulfotransferase (SULT) 2B1b as a Regulator of Cholesterol Metabolism in Prostate Cancer

    Science.gov (United States)

    2015-10-01

    next  subtask.       Subtask 2: Production of infective Lentivirus using co-transfection of HEK293 (pCa cells LNCaP, PC3, DU145, and VCaP...PCa lines. We determined that the level of shRNA expression from a stably intergrated transgene gene delivered by lentivirus was too low...effects  on  SULT2B1b  enzyme  activity  of   cholesterol  sulfate   production  in  vitro.     We  developed  a

  16. The associations between two vital GSTs genetic polymorphisms and lung cancer risk in the Chinese population: evidence from 71 studies.

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    Kui Liu

    Full Text Available BACKGROUND: The genetic polymorphisms of glutathione S-transferase (GSTs have been suspected to be related to the development of lung cancer while the current results are conflicting, especially in the Chinese population. METHODS: Data on genetic polymorphisms of glutathione S-transferase Mu 1 (GSTM1 from 68 studies, glutathione S-transferase theta 1 (GSTT1 from 17 studies and GSTM1-GSTT1 from 8 studies in the Chinese population were reanalyzed on their association with lung cancer risk. Odds ratios (OR were pooled using forest plots. 9 subgroups were all or partly performed in the subgroup analyses. The Galbraith plot was used to identify the heterogeneous records. Potential publication biases were detected by Begg's and Egger's tests. RESULTS: 71 eligible studies were identified after screening of 1608 articles. The increased association between two vital GSTs genetic polymorphisms and lung cancer risk was detected by random-effects model based on a comparable heterogeneity. Subgroup analysis showed a significant relationship between squamous carcinoma (SC, adenocarcinoma (AC or small cell lung carcinoma (SCLC and GSTM1 null genotype, as well as SC or AC and GSTT1 null genotype. Additionally, smokers with GSTM1 null genotype had a higher lung cancer risk than non-smokers. Our cumulative meta-analysis demonstrated a stable and reliable result of the relationship between GSTM1 null genotype and lung cancer risk. After the possible heterogeneous articles were omitted, the adjusted risk of GSTs and lung cancer susceptibility increased (fixed-effects model: ORGSTM1 = 1.23, 95% CI: 1.19 to 1.27, P<0.001; ORGSTT1 = 1.18, 95% CI: 1.10 to 1.26, P<0.001; ORGSTM1-GSTT1 = 1.33, 95% CI: 1.10 to 1.61, P = 0.004. CONCLUSIONS: An increased risk of lung cancer with GSTM1 and GSTT1 null genotype, especially with dual null genotype, was found in the Chinese population. In addition, special histopathological classification of lung cancers and a

  17. Sulfation of chlorotyrosine and nitrotyrosine by human lung endothelial and epithelial cells: Role of the human SULT1A3

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    Yasuda, Shin; Yasuda, Tomoko; Liu, Ming-Yih; Shetty, Sreerama; Idell, Steven; Boggaram, Vijayakumar; Suiko, Masahito; Sakakibara, Yoichi; Fu Jian; Liu, Ming-Cheh

    2011-01-01

    During inflammation, potent reactive oxidants formed may cause chlorination and nitration of both free and protein-bound tyrosine. In addition to serving as biomarkers of inflammation-mediated oxidative stress, elevated levels of chlorotyrosine and nitrotyrosine have been linked to the pathogenesis of lung and vascular disorders. The current study was designed to investigate whether the lung cells are equipped with mechanisms for counteracting these tyrosine derivatives. By metabolic labeling, chlorotyrosine O-[ 35 S]sulfate and nitrotyrosine O-[ 35 S]sulfate were found to be generated and released into the labeling media of human lung endothelial and epithelial cells labeled with [ 35 S]sulfate in the presence of added chlorotyrosine and nitrotyrosine. Enzymatic assays using the eleven known human cytosolic sulfotransferases (SULTs) revealed SULT1A3 as the enzyme responsible for catalyzing the sulfation of chlorotyrosine and nitrotyrosine. Reverse transcription-polymerase chain reaction (RT-PCR) analysis demonstrated the expression of SULT1A3 in the lung endothelial and epithelial cells used in this study. Kinetic constants of the sulfation of chlorotyrosine and nitrotyrosine by SULT1A3 were determined. Collectively, these results suggest that sulfation by SULT1A3 in lung endothelial and epithelial cells may play a role in the inactivation and/or disposal of excess chlorotyrosine and nitrotyrosine generated during inflammation.

  18. Enzimas extracelulares da família Botryosphaeriaceae

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    Pinheiro, Ana Rita Almeida

    2015-01-01

    As espécies da família Botryosphaeriaceae são morfologicamente diversas e descritas como endofíticas, patogénias e saprófitas. Estas são normalmente encontradas numa grande diversidade de hospedeiros. Os fungos patogénicos para plantas Macrophomina phaseolina, Neofusicoccum parvum e Diplodia corticola secretam uma variedade de enzimas extracelulares, tais como proteases e glicosil hidrolases, algumas das quais envolvidas na interação hospedeiro-patogénio. A fim de elucidar a correlação ent...

  19. Inhibidor de la enzima uracilo ADN glicosilasa y usos del mismo

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    Serrano-Heras, Gemma; Bravo, Alicia; Salas, Margarita

    2005-01-01

    Inhibidor de la enzima uracilo adn glicosilasa y usos del mismo Esta invención se refiere a una proteína que inhibe la enzima uracilo ADN glicosilasa (UDG) vírica, para su uso como un agente terapéutico, en particular como un agente antiví

  20. Hypothesis: holiday sudden cardiac death: food and alcohol inhibition of SULT1A enzymes as a precipitant.

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    Eagle, Ken

    2012-10-01

    Sudden cardiac death is a significant health issue, causing millions of deaths worldwide annually. Studies have found that the likelihood of such death is higher in winter. Further studies identified that the highest likelihood occurs on Christmas Day and New Years Day, but not the interim period. Thanksgiving, Independence Day and the Islamic holiday Eid Al-Fitr also show significant increases in the rate of cardiac events or death. A number of mechanisms have been proposed, but none have satisfactorily explained the evidence. This article reviews the data supporting the existence of a holiday cardiac death phenomenon, the involvement of catecholamines and the normal modes of human catecholamine deactivation. Further evidence is reviewed that supports a hypothesized mechanism whereby critical SULT1A catecholamine deactivation enzymes can in some patients be inhibited by naturally-occurring phenols and polyphenols in foods and alcohols. If deactivation is inhibited by holiday consumption excesses, holiday stress or excitement could lead to a buildup of catecholamines that can cause fatal arrhythmias. Awareness of this mechanism could reduce deaths, both through doctor/patient education leading to a moderation in consumption and through the potential identification of patients with a predisposition to SULT1A inhibition. This hypothesis also raises parallels between sudden cardiac death in adults and Sudden Infant Death Syndrome (SIDS). The possible involvement of SULT1A inhibition in SIDS is discussed. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Hypothesis Holiday sudden cardiac death: food and alcohol inhibition of SULT1A enzymes as a precipitant

    Science.gov (United States)

    Eagle, Ken

    2012-01-01

    Sudden cardiac death is a significant health issue, causing millions of deaths worldwide annually. Studies have found that the likelihood of such death is higher in winter. Further studies identified that the highest likelihood occurs on Christmas Day and New Years Day, but not the interim period. Thanksgiving, Independence Day and the Islamic holiday Eid Al-Fitr also show significant increases in the rate of cardiac events or death. A number of mechanisms have been proposed, but none have satisfactorily explained the evidence. This article reviews the data supporting the existence of a holiday cardiac death phenomenon, the involvement of catecholamines and the normal modes of human catecholamine deactivation. Further evidence is reviewed that supports a hypothesized mechanism whereby critical SULT1A catecholamine deactivation enzymes can in some patients be inhibited by naturally-occurring phenols and polyphenols in foods and alcohols. If deactivation is inhibited by holiday consumption excesses, holiday stress or excitement could lead to a buildup of catecholamines that can cause fatal arrhythmias. Awareness of this mechanism could reduce deaths, both through doctor/patient education leading to a moderation in consumption and through the potential identification of patients with a predisposition to SULT1A inhibition. This hypothesis also raises parallels between sudden cardiac death in adults and Sudden Infant Death Syndrome (SIDS). The possible involvement of SULT1A inhibition in SIDS is discussed. Copyright © 2012 John Wiley & Sons, Ltd. PMID:22678655

  2. SULT1A1 genetic polymorphisms and the association between smoking and oral cancer in a case-control study in Brazil

    International Nuclear Information System (INIS)

    Santos, Sabrina S.; Koifman, Rosalina J.; Ferreira, Rafaela M.; Diniz, Lilian F.; Brennan, Paul; Boffetta, Paolo; Koifman, Sergio

    2012-01-01

    Introduction: Oral cancer is a public health problem worldwide, being tobacco and alcohol consumption their main risk factors. Sulfotransferase (SULT) 1A1 (encoded by SULT1A1) is involved in procarcinogens metabolism, such as polycyclic aromatic hydrocarbons (PAHs) present in tobacco smoke. Objective: The aim of this study was to explore the magnitude of association between SULT1A1 gene Arg 213 His polymorphism and oral cancer, and to explore the interaction between such polymorphism and smoking. Methods: A hospital-based case-control study was carried out in Rio de Janeiro, Brazil, during 1999–2002. Epidemiological data and biological samples were obtained from 202 oral cancer patients and 196 sex and age-frequency matched controls without cancer antecedents. Results: No association was observed between Arg 213 His SULT1A1 polymorphism and oral cancer risk in overall analysis (OR = 1.06, 95% CI = 0.71–1.57). The magnitude of association between cigarette smoking and oral cancer was higher in individuals with a SULT1A1 * 1 isoform (wild type, genotype Arg/Arg) (OR = 10.19, 95% CI = 3.90–26.61) than in those with at least one SULT1A1 * 2 allele (genotypes Arg/His + His/His) (OR = 4.50, 95% CI =2.09–9.69). Conclusion: Our results suggest that Arg 213 His SULT1A1 polymorphism may modulate the association between smoking and oral cancer. However, this association needs to be replicated in other studies: due to modest number of cases and controls, the role of chance in the observed association cannot be ruled out.

  3. SULT1A1 genetic polymorphisms and the association between smoking and oral cancer in a case-control study in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Sabrina S.; Koifman, Rosalina J.; Ferreira, Rafaela M.; Diniz, Lilian F. [National School of Public Health/FIOCRUZ, Rio de Janeiro (Brazil); Brennan, Paul [International Agency of Research on Cancer (IARC/WHO), Lyon (France); Boffetta, Paolo [Institute for Translational Epidemiology and Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY (United States); Koifman, Sergio, E-mail: koifman@ensp.fiocruz.br [National School of Public Health/FIOCRUZ, Rio de Janeiro (Brazil)

    2012-12-18

    Introduction: Oral cancer is a public health problem worldwide, being tobacco and alcohol consumption their main risk factors. Sulfotransferase (SULT) 1A1 (encoded by SULT1A1) is involved in procarcinogens metabolism, such as polycyclic aromatic hydrocarbons (PAHs) present in tobacco smoke. Objective: The aim of this study was to explore the magnitude of association between SULT1A1 gene Arg{sup 213}His polymorphism and oral cancer, and to explore the interaction between such polymorphism and smoking. Methods: A hospital-based case-control study was carried out in Rio de Janeiro, Brazil, during 1999–2002. Epidemiological data and biological samples were obtained from 202 oral cancer patients and 196 sex and age-frequency matched controls without cancer antecedents. Results: No association was observed between Arg{sup 213}His SULT1A1 polymorphism and oral cancer risk in overall analysis (OR = 1.06, 95% CI = 0.71–1.57). The magnitude of association between cigarette smoking and oral cancer was higher in individuals with a SULT1A1{sup *}1 isoform (wild type, genotype Arg/Arg) (OR = 10.19, 95% CI = 3.90–26.61) than in those with at least one SULT1A1{sup *}2 allele (genotypes Arg/His + His/His) (OR = 4.50, 95% CI =2.09–9.69). Conclusion: Our results suggest that Arg{sup 213}His SULT1A1 polymorphism may modulate the association between smoking and oral cancer. However, this association needs to be replicated in other studies: due to modest number of cases and controls, the role of chance in the observed association cannot be ruled out.

  4. Produção de enzimas lignoceluloliticas e proteinas unicelulares por chrysonilia sitophila TFB 27441

    OpenAIRE

    Jaime Patricio Rodrigues Gutierrez

    1987-01-01

    Resumo: Estudou-se as enzimas celulolíticas e lignolíticas produzidas pelo microorganismo Chrysonlila sitophila TFB-27441 que foi isolado do trato intestinal de um inseto xilófago. A produção de celulases foi estudada utilizando como fonte de carbono no meio de cultivo gllcose, a-celuIose e a-celulose pré-tratada fotoquimicamente. As enzimas estudadas foram b-D-glicosidase, endo-1,4-b-D-glicanase e a atividade cetulolítica total foi estimada utilizando papel de filtro como substrato. A ativid...

  5. Actividad y expresión de enzimas convertidoras de angiotensina en neoplasias renales

    OpenAIRE

    Varela González, Pedro

    2015-01-01

    146 p. En el presente trabajo de tesis doctoral se realizó un análisis de 3 enzimas convertidoras de angiotensina (ACE, ACE2 y APA) en diferentes histotipos de neoplasias renales. Su objetivo fue conocer la implicación de estas enzimas en la carcinogénesis renal, en el desarrollo de los diferentes histotipos y en el comportamiento agresivo de estos tumores.Mediante diferentes técnicas (PCR, inmunohistoquímica, espectrofluorimetría, espectrofotometría) se analizó la expresión génica y proté...

  6. SULT1A3-Mediated Regiospecific 7-O-Sulfation of Flavonoids in Caco-2 Cells Can Be Explained by the Relevant Molecular Docking Studies

    Science.gov (United States)

    Meng, Shengnan; Wu, Baojian; Singh, Rashim; Yin, Taijun; Morrow, John Kenneth; Zhang, Shuxing; Hu, Ming

    2012-01-01

    Flavonoids are the polyphenolic compounds with various claimed health benefits, but the extensive metabolism by uridine-5'-diphospho-glucuronosyltransferases (UGTs) and sulfotransferases (SULTs) in liver and intestine led to poor oral bioavailabilities. The effects of structural changes on the sulfonation of flavonoids have not been systemically determined, although relevant effects of structural changes on the glucuronidation of flavonoids had. We performed the regiospecific sulfonation of sixteen flavonoids from five different subclasses of flavonoids, which are represented by apigenin (flavone), genistein (isoflavone), naringenin (flavanone), kaempherol (flavonol), and phloretin (chalcone). Additional studies were performed using 4 mono-hydroxyl flavonoids with –OH group at 3, 4’, 5 or 7 position, followed by 5 di-hydroxyl-flavonoids, and 2 tri-hydroxyl flavonoids by using expressed human SULT1A3 and Caco-2 cell lysates. We found that these compounds were exclusively sulfated at the 7-OH position by SULT1A3 and primarily sulfated at 7-OH position in Caco-2 cell lysates with minor amounts of 4’-O-sulfates formed as well. Sulfonation rates measured using SULT1A3 and Caco-2 cell lysates were highly correlated at substrate concentrations of 2.5 and 10 µM. Molecular docking studies provided structural explanations as to why sulfonation only occurred at the 7-OH position of flavones, flavonols and flavanones. In conclusion, molecular docking studies explain why SULT1A3 exclusively mediates sulfonation at the 7-OH position of flavones/flavonols, and correlation studies indicate that SULT1A3 is the main isoform responsible for flavonoid sulfonation in the Caco-2 cells. PMID:22352375

  7. Biological monitoring and the influence of genetic polymorphism of As3MT and GSTs on distribution of urinary arsenic species in occupational exposure workers.

    Science.gov (United States)

    Janasik, Beata; Reszka, Edyta; Stanislawska, Magdalena; Wieczorek, Edyta; Fendler, Wojciech; Wasowicz, Wojciech

    2015-08-01

    To examine the differences in urinary arsenic metabolism patterns in men affected by occupational exposure, we performed a study on 149 participants—workers of a copper mill and 52 healthy controls without occupational exposure. To elucidate the role of genetic factors in arsenic (As) metabolism, we studied the associations of six polymorphisms: As3MT Met287Thr (T>C) in exon 9; As3MT A>G in 5'UTR; As3MT C>G in intron 6; As3MT T>G in intron 1; GSTP1 Ile105Val and GSTO2 T>C. Air samples were collected using individual samplers during work shift. Urine samples were analyzed for total arsenic and arsenic chemical forms (As(III); As(V), MMA, DMA, AsB) using HPLC-ICP-MS. A specific polymerase chain reaction was done for the amplification of exons and flanking regions of As3MT and GSTs. The geometric mean arsenic concentrations in the air were 27.6 ± 4.9 µg/m(3). A significant correlation (p iAs +MMA and iAs. As3MT (rs3740400) GG homozygotes showed significantly (p iAs (21.8 ± 2.0) in urine than GC+CC heterozygotes (16.0 ± 2.1). A strong association between the gene variants and As species in urine was observed for GSTO2 (rs156697) polymorphism. The findings of the study point out that the concentration of iAs or the sum of iAs + MMA in urine can be a reliable biological indicator of occupational exposure to arsenic. This study demonstrates that As3MT and/or GSTs genotype may influence As metabolism. Nevertheless, further studies investigating genetic polymorphism in occupational conditions are required.

  8. Combined effects of GSTO1 and SULT1A1 polymorphisms and cigarette smoking on urothelial carcinoma risk in a Taiwanese population

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    Min-Che Tung

    2014-09-01

    Conclusion: The present study provided epidemiological evidence for a significantly increased risk of UCB in ever smokers with the Ala/Ala genotype of the GSTO1 gene and the Arg/Arg genotype of the SULT1A1 gene.

  9. Combined effects of NQO1 Pro187Ser or SULT1A1 Arg213His polymorphism and smoking on bladder cancer risk: Two meta-analyses

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    Xiao-Chun Wang

    2017-10-01

    Full Text Available Objectives: Objectives: Cigarette smoking is the major risk factor of bladder cancer via exposure to chemical carcinogens. Nicotinamide adenine dinucleotide phosphate (NADP+: quinine oxidoreductase 1 (NQO1 and sulfotransferase 1A1 (SULT1A1 have been reported to involve in the metabolism of polycyclic aromatic hydrocarbons (PAHs and aromatic amines. Therefore, the risk of bladder cancer (BC may be influenced by polymorphisms in the genes that modulate metabolic detoxification in particular by interacting with cigarette smoking. Considering the limited power by the individual studies with a relatively small sample size, especially when analyzing the combined effect of polymorphisms in NQO1 and SULT1A1 genes and smoking, these 2 meta-analyses have aimed to clarify the combined effects of them on BC risk by integrating related studies. Material and Methods: Two meta-analyses included 1341 cases and 1346 controls concerning NQO1 Pro187Ser and smoking, and 1921 cases and 1882 controls on SULT1A1 Arg213His and smoking were performed. Odds ratios (OR and 95% confidence intervals (CI were used for assessing the strength of the association. Results: The result has demonstrated that smokers with NQO1 Pro/Ser or Ser/Ser genotypes have a prominent association with the risk of BC as compared with non-smokers with NQO1 Pro/Pro genotype, with OR equal to 3.71 (95% CI: 2.87–4.78, pheterogeneity = 0.376. Besides, smokers carrying SULT1A1 Arg/Arg genotypes were observed to confer 2.38 fold increased risk of BC (95% CI: 1.44–3.93, pheterogeneity = 0.001 when compared with non-smokers with SULT1A1 Arg/Arg or His/His genotypes. Conclusions: These findings have suggested that the NQO1 Pro187Ser or SULT1A1 Arg213His polymorphism combination with smoking significantly confer susceptibility to BC. Int J Occup Med Environ Health 2017;30(5:791–802

  10. Combined effects of NQO1 Pro187Ser or SULT1A1 Arg213His polymorphism and smoking on bladder cancer risk: Two meta-analyses.

    Science.gov (United States)

    Wang, Xiao-Chun; Wang, Jian; Tao, Hui-Hui; Zhang, Chao; Xu, Li-Fa

    2017-07-14

    Objectives: Cigarette smoking is the major risk factor of bladder cancer via exposure to chemical carcinogens. Nicotinamide adenine dinucleotide phosphate (NADP+): quinine oxidoreductase 1 (NQO1) and sulfotransferase 1A1 (SULT1A1) have been reported to involve in the metabolism of polycyclic aromatic hydrocarbons (PAHs) and aromatic amines. Therefore, the risk of bladder cancer (BC) may be influenced by polymorphisms in the genes that modulate metabolic detoxification in particular by interacting with cigarette smoking. Considering the limited power by the individual studies with a relatively small sample size, especially when analyzing the combined effect of polymorphisms in NQO1 and SULT1A1 genes and smoking, these 2 meta-analyses have aimed to clarify the combined effects of them on BC risk by integrating related studies. Two meta-analyses included 1341 cases and 1346 controls concerning NQO1 Pro187Ser and smoking, and 1921 cases and 1882 controls on SULT1A1 Arg213His and smoking were performed. Odds ratios (OR) and 95% confidence intervals (CI) were used for assessing the strength of the association. The result has demonstrated that smokers with NQO1 Pro/Ser or Ser/Ser genotypes have a prominent association with the risk of BC as compared with non-smokers with NQO1 Pro/Pro genotype, with OR equal to 3.71 (95% CI: 2.87-4.78, pheterogeneity = 0.376). Besides, smokers carrying SULT1A1 Arg/Arg genotypes were observed to confer 2.38 fold increased risk of BC (95% CI: 1.44-3.93, pheterogeneity = 0.001) when compared with non-smokers with SULT1A1 Arg/Arg or His/His genotypes. These findings have suggested that the NQO1 Pro187Ser or SULT1A1 Arg213His polymorphism combination with smoking significantly confer susceptibility to BC. Int J Occup Med Environ Health 2017;30(5):791-802. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  11. Curious Cases of the Enzymes / Neobiča Istorija Enzima

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    Ulusu Nuriye Nuray

    2015-07-01

    Full Text Available : Život oko nas uglavnom se zasniva na biološkoj katalizi, pa bi se čak, u nekakvoj neromantičnoj priči, život mogao opisati kao niz hemijskih reakcija koje regulišu glavni principi termodinamike. U davnoj prošlosti, ku­canje srca bilo je znak dobrog zdravlja, međutim, za mene, najvažniju ulogu ima upravo prisustvo enzima... Mada ne obraćamo često pažnju na to, istorija enzimologije stara je koliko i sam ljudski rod i seže daleko u prošlost. CVaj rad posvećen je baš tim počecima u ovoj veoma zanimljivoj nauci, koja je u prošlosti ostavila traga na našim životima i koja će u budućnosti učiniti da život bude mnogo pro­duktivniji za čovečanstvo. Između čoveka i enzima postojao je oduvek jedan delikatan, suštinski važan odnos. Suočen s nepoznatom i neprijateljski nastrojenom prirodom punom grabljivaca, preistorijski čovek rano je otkrio lekovita svojstva biljaka, i to metodom probe i greške. Štaviše, slučajno su otkriveni inhibitori enzima, čime je, grubo rečeno, još tada otvorena nova oblast istraživanja. Oi biljni derivati koji su imali ulogu inhibitora enzima pomagali su preistorijskom čoveku u njegovoj borbi da opstane i zaštiti se od grabljiva­ca; prilikom lova i ribolova... Kasnije kroz istoriju, sa nepro- menjenom svrhom opstanka i poboljšanja kvaliteta života, enzimologija je iz korena transformisana, a metodologiju »probe i greške« iz praistorije zamenile su racionalne naučne teorije.

  12. INDUCCIÓN DE DOS ENZIMAS PECTOLÍTICAS EN EL MODELO Fusarium oxysporum f. sp. dianthi - CLAVEL

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    Liliana Goméz García

    2008-03-01

    Full Text Available Se estudió por ensayos in vitro la posible participación de las enzimas endopoligalacturonasa (PG (EC.3.2.1.15 y pectato liasa (PL (EC.4.2.2.2, consideradas factores de virulencia en el proceso de infección del clavel por el hongo Fusarium oxysporum f. sp. dianthi (FOD.Los resultados muestran la inducción de la expresión de la enzima PG en presencia de los inductores artificiales, ácido poligalacturónico (APG y pectina, y un nivel de expresión muy bajo en cultivos con pared celular (PC de clavel de variedades resistente y susceptible. La enzima PL no presentó expresión en presencia de inductores artificiales (APG y pectina, mientras que en cultivos inducidos con pared celular de raíz presentó un alto nivel de expresión.

  13. Perspectiva en el desarrollo de las enzimas industriales a partir de la inteligencia tecnológica

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    Óscar Fernando Castellanos Domínguez

    2006-05-01

    Full Text Available El desarrollo de tecnologías emergentes implica el reto permanente de utilizar nuevas herramientas de gestión tecnológica. La ingeniería de enzimas y su respectiva tecnología, en el contexto de la biotecnología, es una de las áreas del conocimiento sobre las cuales reiterativamente se plantean grandes expectativas como posible generador de ventaja competitiva en economías emergentes como la colombiana. Sin embargo, varias décadas de investigación en este campo aún no arrojan resultados importantes en la producción de enzimas y su aplicación en procesos industriales. El presente artículo se propone aplicar los componentes de un sistema de inteligencia tecnológica para el desarrollo de la tecnología de enzimas. Inicialmente se hace énfasis en los procesos de cienciometría retomados en ejercicios de mapeo de patentes, vigilancia tecnológica y evaluación de proyectos colombianos en la red ScienTI de Colciencias, realizados para las enzimas utilizadas, tanto en la industria de alimentos en la obtención de hidrolizados, como en la industria de textiles. Se documenta un ejemplo de estudio Delphi en el contexto de la prospectiva de las enzimas industriales en la biotecnología en general. Posteriormente, se evidencia el aprendizaje que se puede generar a partir del análisis de un líder del sector, a través de un benchmarking organizacional. Finalmente, retomando las bases del sistema de inteligencia tecnológica se discute su aporte a la generación de estrategias de productividad y competitividad de la aplicación de las enzimas industriales.

  14. Enzimas fibrolíticas exógenas en la digestibilidad in vitro de cinco ecotipos de Brachiaria

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    Juan H. Avellaneda-Cevallos

    2007-01-01

    Full Text Available En zi mas fi bro lí ti cas exó ge nas en la di ges ti bi li dad in vi tro de cin co eco ti pos de Bra chia ria. Este experimento se llevó a cabo en la Estación Experimental del Colegio de Postgraduados, en Montecillo, Estado de México, México, durante el 25 abril y el 27 noviembre de 2002. Se usó la primera fase de la técnica de Tilley y Terry (3, 6, 12, 24, 48, 72 h incubación con el objetivo de medir el efecto de un compuesto enzimático fibrolítico exógeno (enzima; Fibrozyme®; 0 y 1,5 g enzima/kg MS en la digestibilidad in vitro (DIV de MS, FDN y FDA de henos de cinco ecotipos de Brachiaria [brizantha var. Toledo (BT; ruziziensis x decumbens CIAT 46024 (RD; decumbens var. Señal (DS; ruziziensis x brizantha CIAT 36061 cv. Mulato (RBM; brizantha var. Insurgente (BI]. La DIVMS a las 48 y 72 h, para 0 y 1,5 g enzima, fue mayor (p<0,05 para los ecotipos BT y BI, respecto a RD, DS y RBM. La DIVFDN a las 48 y 72 h, para 0 y 1,5 g enzima, fue mayor (p<0,05 para BT y BI, respecto a RD, DS y RBM. La enzima aumentó (p<0,05 la DIVFDN sólo para el ecotipo RD a las 72 h; además, incrementó la DIVFDA para BT a 12 h; BT y DS a 24 h; BT, RD y BI a 48 h. Por tanto, las enzimas fibrolíticas aumentaron la digestibilidad in vitro de la pared celular de cinco ecotipos de Brachiaria.

  15. Electrodo biológico con la enzima hidrogenasa, procedimiento de obtención y sus aplicaciones

    OpenAIRE

    Fernández López, Víctor Manuel; López de Lacey, Antonio; Rüdiger Ortiz, Olaf

    2005-01-01

    Electrodo biológico con la enzima hidrogenasa, procedimiento de obtención y sus aplicaciones. En la presente invención se protegen electrodos biológicos modificados con enzimas hidrogenasas (ánodos) mediante los cuales es posible obtener energía eléctrica del hidrógeno en una configuración típica de pilas de combustible; asimismo, con estos electrodos modificados con hidrogenasa (cátodos) es posible producir hidrógeno a partir de agua en una configuración típica de cél...

  16. Empleo de polielectrolitos inteligentes para desarrollar matrices insolubles con capacidad bioseparativa de enzimas de importancia biotecnológica

    OpenAIRE

    Woitovich Valetti, Nadia

    2016-01-01

    Con los avances de la ciencia moderna, principalmente en el campo de la biotecnología, la obtención de enzimas para uso industrial ha creado la necesidad de desarrollar nuevas metodologías para la purificación de las mismas. Los métodos de escalado clásicos para la purificación de enzimas emplean precipitación con sales o solventes. Dichas técnicas producen gran cantidad de residuos que muchas veces son difíciles de reciclar, incrementando los costos del proceso. Los nuevos protocolos deben r...

  17. INDUCCIÓN DE DOS ENZIMAS PECTOLÍTICAS EN EL MODELO Fusarium oxysporum f. sp. dianthi - CLAVEL

    OpenAIRE

    Gómez García, Liliana; Martínez, Sixta Tulia

    2005-01-01

    Se estudió por ensayos in vitro la posible participación de las enzimas endopoligalacturonasa (PG) (EC.3.2.1.15) y pectato liasa (PL) (EC.4.2.2.2), consideradas factores de virulencia en el proceso de infección del clavel por el hongo Fusarium oxysporum f. sp. dianthi (FOD). Los resultados muestran la inducción de la expresión de la enzima PG en presencia de los inductores artificiales, ácido poligalacturónico (APG) y pectina, y un nivel de expresión muy bajo en cultivos con pared celular (PC...

  18. Metabolic Phase I (CYPs) and Phase II (GSTs) Gene Polymorphisms and Their Interaction with Environmental Factors in Nasopharyngeal Cancer from the Ethnic Population of Northeast India.

    Science.gov (United States)

    Singh, Seram Anil; Ghosh, Sankar Kumar

    2017-09-26

    Multiple genetic and environmental factors and their interaction are believed to contribute in the pathogenesis of Nasopharyngeal Cancer (NPC). We investigate the role of Metabolic Phase I (CYPs) and Phase II (GSTs) gene polymorphisms, gene-gene and gene-environmental interaction in modulating the susceptibility to NPC in Northeast India. To determine the association of metabolic gene polymorphisms and environmental habits, 123 cases and 189 controls blood/swab samples were used for PCR and confirmed by Sanger sequencing. Analysis for GSTM1 and GSTT1 gene polymorphism was done by multiplex PCR. The T3801C in the 3'- flanking region of CYP1A1 gene was detected by PCR-RFLP method. The Logistic regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). The GSTM1 null genotype alone (OR = 2.76) was significantly associated with NPC risk (P < 0.0001). The combinations of GSTM1 null and GSTT1 null genotypes also higher, 3.77 fold (P < 0.0001), risk of NPC, while GSTM1 null genotype along with CYP1A1 T3801C TC + CC genotype had 3.22 (P = 0.001) fold risk. The most remarkable risk was seen among individual carrying GSTM1 null, GSTT1 null genotypes and CYP1A1 T3801C TC + CC genotypes (OR = 5.71, P = 0.001). Further; analyses demonstrate an enhanced risk of NPC in smoked meat (OR = 5.56, P < 0.0001) and fermented fish consumers (OR = 5.73, P < 0.0001) carrying GSTM1 null genotype. An elevated risk of NPC was noted in smokers (OR = 12.67, P < 0.0001) and chewers (OR = 5.68, P < 0.0001) with GSTM1 null genotype. However, smokers had the highest risk of NPC among individuals carrying GSTT1 null genotype (OR = 4.46, P = 0.001) or CYP1A1 T3801C TC + CC genotype (OR = 7.13, P < 0.0001). The association of null genotypes and mutations of metabolic neutralizing genes along with the environmental habits (tobacco smokers and chewers, smoke meat, fermented fishes) can be used as a possible biomarker for

  19. Impacto do polimorfismo genetico da enzima conversora da angiotensina no remodelamento cardiaco

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    Felipe Neves de Albuquerque

    2014-01-01

    Full Text Available Fundamento: O papel dos polimorfismos genéticos da enzima de conversão da angiotensina na insuficiência cardíaca, como preditor de desfechos ecocardiográficos, ainda não está estabelecido. é necessário identificar o perfil local para observar o impacto desses genótipos na população brasileira, sendo inédito o estudo da insuficiência cardíaca de etiologia exclusivamente não isquêmica em seguimento mais longo que 5 anos. Objetivo: Determinar a distribuição das variantes do polimorfismo genético da enzima de conversão da angiotensina e sua relação com a evolução ecocardiográfica de pacientes com insuficiência cardíaca de etiologia não isquêmica. Métodos: Análise secundária de prontuários de 111 pacientes e identificação das variantes do polimorfismo genético da enzima de conversão da angiotensina, classificadas como DD (Deleção/Deleção, DI (Deleção/Inserção ou II (Inserção/Inserção. Resultados: As médias da coorte foram: seguimento de 64,9 meses, idade de 59,5 anos, 60,4% eram homens, 51,4% eram brancos, 98,2% faziam uso de betabloqueadores e 89,2% de inibidores da enzima de conversão da angiotensina ou de bloqueador do receptor da angiotensina. A distribuição do polimorfismo genético da enzima de conversão da angiotensina foi: 51,4% de DD; 44,1% de DI; e 4,5% de II. Não se observou nenhuma diferença das características clínicas ou de tratamento entre os grupos. O diâmetro sistólico do ventrículo esquerdo final foi a única variável ecocardiográfica isolada significativamente diferente entre os polimorfismos genéticos da enzima de conversão da angiotensina: 59,2 ± 1,8 para DD versus 52,3 ± 1,9 para DI versus 59,2 ± 5,2 para II (p = 0,029. No seguimento ecocardiográfico, todas as variáveis (diferença entre a fração de ejeção do ventrículo esquerdo da última e da primeira consulta; diferença entre o diâmetro sistólico do ventrículo esquerdo da última e da primeira

  20. ASS and SULT2A1 are Novel and Sensitive Biomarkers of Acute Hepatic Injury-A Comparative Study in Animal Models.

    Science.gov (United States)

    Prima, Victor; Cao, Mengde; Svetlov, Stanislav I

    2013-01-10

    Liver and kidney damage associated with polytrauma, endotoxic shock/sepsis, and organ transplantation, are among the leading causes of the multiple organ failure. Development of novel sensitive biomarkers that detect early stages of liver and kidney injury is vital for the effective diagnostics and treatment of these life-threatening conditions. Previously, we identified several hepatic proteins, including Argininosuccinate Synthase (ASS) and sulfotransferases which were degraded in the liver and rapidly released into circulation during Ischemia/Reperfusion (I/R) injury. Here we compared sensitivity and specificity of the newly developed sandwich ELISA assays for ASS and the sulfotransferase isoform SULT2A1 with the standard clinical liver and kidney tests Alanine Aminotransferase (ALT) and Aspartate Transaminase (AST) in various pre-clinical models of acute injury. Our data suggest that ASS and SULT2A1 have superior characteristics for liver and kidney health assessment in endotoxemia, Ischemia/Reperfusion (I/R), chemical and drug-induced liver injury and may be of high potential value for clinical applications.

  1. Selective reduction in the expression of UGTs and SULTs, a novel mechanism by which piperine enhances the bioavailability of curcumin in rat.

    Science.gov (United States)

    Zeng, Xiaohui; Cai, Dake; Zeng, Qiaohuang; Chen, Zhao; Zhong, Guoping; Zhuo, Juncheng; Gan, Haining; Huang, Xuejun; Zhao, Ziming; Yao, Nan; Huang, Dane; Zhang, Chengzhe; Sun, Dongmei; Chen, Yuxing

    2017-01-01

    Curcumin (CUR) is known to exert numerous health-promoting effects in pharmacological studies, but its low bioavailability hinders the development of curcumin as a feasible therapeutic agent. Piperine (PIP) has been reported to enhance the bioavailability of curcumin, but the underlying mechanism remains poorly understood. In an attempt to find the mechanism by which piperine enhances the bioavailability of curcumin, the dosage ratio (CUR: PIP) and pre-treatment with piperine were hypothesized as key factors for improving the bioavailability in this combination. Therefore, combining curcumin with piperine at various dose ratios (1:1 to 100:1) and pre-dosing with piperine (0.5-8 h prior to curcumin) were designed to investigate their contributions to the pharmacokinetic parameters of curcumin in rats and their effects on the expression of UGT and SULT isoforms. It was shown that the C max and AUC 0-t of curcumin were slightly increased by 1.29 and 1.67 fold at a ratio of 20:1, while curcumin exposure was enhanced significantly in all the piperine pre-treated rats (0.5-8 h), peaking at 6 h (a 6.09-fold and 5.97-fold increase in C max and AUC 0-t , p bioavailability of curcumin through the reversible and selective inhibition of UGTs and SULTs. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Enzimas de restricción de bacterias nativas de Nicaragua

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    lan Roustan-Espinosa

    2000-02-01

    Full Text Available Los avances de la ingeniería genética y la biología molecular han propiciado la utilización de bacterias en la industria biotecnológica. En este trabajo se presenta la identificación y caracterización de enzimas de restricción presentes en bacterias recolectadas en medios acuosos de Nicaragua. Se encontró actividad de restricción en el 25% del total de bacterias analizadas. Se abordan los procesos de purificación de extractos de proteínas de bacterias con actividades de Sau961 y Pvull. Este trabajo es un esfuerzo dirigido a la implementación de técnicas modernas de biotecnología en Nicaragua.

  3. La enzima quinasa dependiente de 5´-adenosil monofosfato (ampk): perspectivas terapéuticas

    OpenAIRE

    Sánchez Junco, Diana

    2016-01-01

    En este trabajo nos centraremos en el estudio de la enzima quinasa dependiente de 5´-adenosil monofosfato (AMPK). La AMPK actúa como un sensor de energía y nutrientes y regula el balance energético. Se activa con el aumento de la relación AMP/ATP dentro de la célula y está implicada en numerosos procesos metabólicos, destacando la captación de glucosa y de ácidos grasos por la célula. La AMPK está formada por tres subunidades: α, β y γ, cada una de ellas con varias isoformas. Cabe destacar...

  4. Enzimas proteolíticas relacionadas con la enfermedad periodontal inflamatoria

    Directory of Open Access Journals (Sweden)

    Bárbara E. García Triana

    1998-08-01

    Full Text Available La enfermedad periodontal inflamatoria ocasiona la destrucción de los tejidos que protegen y soportan al diente; es por eso de gran importancia el papel que pueden desempeñar las enzimas que sean capaces de degradar la matriz del tejido conectivo, como las enzimas proteolíticas. Existen evidencias de que las metaloproteinasas de la matriz, las proteasas leucocitarias y las bacterianas, pueden participar en la etiopatogenia de esta enfermedad. Su acción es regulada en los tejidos, por la presencia de inhibidores específicos, de manera que un desbalance proteasas-inhibidores a favor de los primeros, conduciría a la destrucción de las proteínas de la matriz del tejido conectivo. A su vez, en la actividad proteolítica influyen diferentes factores, que de manera global, inducen un fenotipo degradativo o formativo, y que por lo tanto, podrían estar involucrados en la etiopatogenia de la enfermedad periodontal inflamatoria.The periodontal disease brings about the destruction of the protective and supporting tissues of the teeth, therefore, the role of enzymes capable of degrading connective tissue matrix is of great importance. There are evidences of the possible involvement of the matrix metalloproteinases, leukocyte proteases and bacterial proteases in the pathogenesis of such disease. Their action is controlled by specific inhibitors in the tissues. This means that any protease-inhibitor imbalance favouring the presence of proteases may lead to the destruction of matrix connective tissue. In turn, proteolytic activity is influenced by different factors that globally induce a degradative or formative phenotype, and thus, may be involved in the pathogenesis of the periodontal disease.

  5. Baseline frequency of chromosomal aberrations and sister chromatid exchanges in peripheral blood lymphocytes of healthy individuals living in Turin (North-Western Italy): assessment of the effects of age, sex and GSTs gene polymorphisms on the levels of genomic damage.

    Science.gov (United States)

    Santovito, Alfredo; Cervella, Piero; Delpero, Massimiliano

    2016-05-01

    The increased exposure to environmental pollutants has led to the awareness of the necessity for constant monitoring of human populations, especially those living in urban areas. This study evaluated the background levels of genomic damage in a sample of healthy subjects living in the urban area of Turin (Italy). The association between DNA damage with age, sex and GSTs polymorphisms was assessed. One hundred and one individuals were randomly sampled. Sister Chromatid Exchanges (SCEs) and Chromosomal Aberrations (CAs) assays, as well as genotyping of GSTT1 and GSTM1 genes, were performed. Mean values of SCEs and CAs were 5.137 ± 0.166 and 0.018 ± 0.002, respectively. Results showed age and gender associated with higher frequencies of these two cytogenetic markers. The eldest subjects (51-65 years) showed significantly higher levels of genomic damage than younger individuals. GSTs polymorphisms did not appear to significantly influence the frequencies of either markers. The CAs background frequency observed in this study is one of the highest reported among European populations. Turin is one of the most polluted cities in Europe in terms of air fine PM10 and ozone and the clastogenic potential of these pollutants may explain the high frequencies of chromosomal rearrangements reported here.

  6. A regeneração hepática e os inibidores da enzima conversora da angiotensina

    Directory of Open Access Journals (Sweden)

    Fernando Silva Ramalho

    2000-01-01

    Full Text Available No presente estudo, o autor aborda conceitos fundamentais acerca do fenômeno regenerativo hepático, seguido de alguns aspectos importantes relacionados ao sistema calicreína-cininas. A associação entre os inibidores da enzima conversora da angiotensina, a bradicinina e a regeneração hepática é discutida à luz de estudos recentes, que revelam um papel estimulante das cininas sobre a proliferação hepatocelular. Os inibidores da enzima conversora da angiotensina, extremamente utilizados no tratamento clínico da hipertensão arterial sistêmica, da insuficiência cardíaca congestiva e da nefropatia diabética, também são capazes de favorecer a regeneração hepática.

  7. BIOENSAIO PARA DETERMINAÇÃO DA RESISTÊNCIA DE PLANTAS DANINHAS AOS HERBICIDAS INIBIDORES DA ENZIMA ALS

    Directory of Open Access Journals (Sweden)

    CHRISTOFFOLETI PEDRO JACOB

    2001-01-01

    Full Text Available Com o uso intensivo de herbicidas inibidores da acetolactato sintase (ALS em áreas cultivadas com soja, no município de São Gabriel d'Oeste (MS, Brasil, selecionou-se um biótipo resistente da planta daninha Bidens pilosa. A confirmação bioquímica desta resistência, no entanto, é muito difícil de ser feita em campo. Assim, realizou-se um bioensaio com o objetivo de testar a sensibilidade da ALS desse biótipo aos herbicidas inibidores dessa enzima, por meio da aplicação simultânea de herbicidas inibidores da ALS e da KARI (cetoácido reductoisomerase. Para a inibição desta última enzima, utilizou-se o teste CPCA (ácido 1,1-ciclopropanodicarboxílico. Por ele, confirmou-se que a resistência do biótipo de Bidens pilosa é decorrente da insensibilidade da ALS aos herbicidas, que visam inibi-la; pois, quanto maior a quantidade de acetoína, maior é a atividade da enzima e mais intensa a coloração desenvolvida, proporcionando maiores valores nas leituras de absorbância.

  8. Actividad antiinflamatoria de la enzima superóxido dismutasa (SOD), purificada de la especie Allium sativum (ajo)

    OpenAIRE

    Soberón, Mercedes; Suárez, Silvia; Arnao, Inés; Guija, Emilio; Troncoso, Luzmila; Rojas, Luis; Saldaña, Ítalo; Cordero, Adriana

    2013-01-01

    Objetivos: Demostrar la actividad antiinflamatoria de la enzima superóxido dismutasa (SOD) purificada de Allium sativum (ajo). Diseño: Experimental. Institución: Centro de Investigación de Bioquímica y Nutrición, Facultad de Medicina, UNMSM Material biológico: Ratas y Allium sativum. Principales medidas de resultados: Muestra de ajo triturada con tampón fosfato 50 mM pH 7,4, incubada 40 minutos y filtrada; fue sometida a extracción con cloroformo:etanol 1:1 (v/v). Se descartó la fase acuosa. ...

  9. Estudio de la expresión de enzimas del metabolismo de aminoácidos en lactococcus lactis

    OpenAIRE

    García Cayuela, Tomás

    2011-01-01

    Los aminoácidos son fundamentales para la supervivencia y el desarrollo de bacterias. Son las principales fuentes de nitrógeno y están implicados en la producción de energía, el control del pH intracelular y la regeneración de cofactores. Además, son los precursores de una larga variedad de compuestos volátiles en Lactococcus lactis y, por ello, diversas enzimas son consideradas clave para su formación, como aminotransferasas, deshidrogenasas, liasas y decarboxilasas, entre otras. Estas enzim...

  10. Alteração de enzimas hepáticas em trabalhadores de refinaria de petróleo

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    Carvalho Fernando Martins

    2006-01-01

    Full Text Available OBJETIVO: A exposição ocupacional típica de uma refinaria de petróleo pode alterar a função hepática de seus trabalhadores. Assim, o objetivo do estudo foi identificar fatores de risco de alterações em enzimas hepáticas em trabalhadores de uma refinaria de petróleo. MÉTODOS: Os trabalhadores de uma refinaria de petróleo, localizada em São Francisco do Conde, Estado da Bahia, eram submetidos a exames periódicos anuais de 1982 a1998. O estudo caso-controle investigou todos os 150 casos de indivíduos com alteração simultânea de gama-glutamil transferase e de alanino amino transferase, de pelo menos 10% acima do valor de referência. Como controles, foram selecionados 150 indivíduos sem quaisquer alterações de enzimas hepáticas ou de bilirrubinas, desde a sua admissão. Foram calculadas as razões de chance e respectivos intervalos de confiança de 95% a partir de modelos de regressão logística. RESULTADOS: Em todos os setores de produção, o risco de alteração de enzimas hepáticas foi significantemente mais elevado do que no setor administrativo (RC=5,7; IC 95%: 1,7-18,4, estando controlados os efeitos do álcool, obesidade e antecedentes médicos de hepatite. No período 1992-1994 foram registrados 89 casos, 88 deles provieram dos diversos setores da produção. CONCLUSÕES: A exposição ocupacional desempenha papel importante na determinação de alterações de enzimas hepáticas em trabalhadores do refino de petróleo, além dos fatores de risco eminentemente biológicos e/ou comportamentais como obesidade e o consumo de álcool.

  11. Las lipasas: enzimas con potencial para el desarrollo de biocatalizadores inmovilizados por adsorción interfacial

    OpenAIRE

    Jorge González-Bacerio; Jairo Rodríguez Hernández; Alberto del Monte Martínez

    2010-01-01

    Las lipasas son enzimas con propiedades funcionales muy interesantes que permiten su utilización práctica en diversos campos de las industrias agroquímica, farmacéutica, de detergentes y alimentaria, así como en química fina. Entre las aplicaciones más importantes de estas moléculas se encuentran: la resolución de mezclas racémicas, la obtención de compuestos ópticamente puros y la bioconversión de principios activos. En este trabajo se presenta una amplia revisión del tema, que abarca desde ...

  12. Produção e avaliação de enzimas fibrolíticas exógenas na ensilagem de milho

    OpenAIRE

    Lara, Erika Christina [UNESP

    2013-01-01

    O presente trabalho avaliou a produção de enzimas fibroliticas exógenas obtidas a partir da fermentação fúngica e sua aplicação em diferentes doses na ensilagem de milho. Para isso, o projeto foi dividido em dois experimentos, sendo o primeiro caracterizado pela produção de enzimas e sua estabilidade em condições ruminais. Cinco amostras de diferentes locais foram coletadas e 45 fungos foram isolados e avaliados quanto a produção de xilanases e celulases. O micro-organismo selecionado como o ...

  13. ESTUDOS TEÓRICOS E DE MODELAGEM MOLECULAR IN SILICO APLICADOS À INTERAÇÃO ENTRE A ENZIMA DELTA-AMINOLEVULINATO DESIDRATASE E DISSELENETOS DE DIARILA

    OpenAIRE

    Rogério de Aquino Saraiva

    2013-01-01

    A enzima δ-aminolevulinato desidratase (δ-ALA-D) é uma metaloproteína essencial em vários processos biológicos, uma vez que é responsável por catalisar a formação de porfobilinogênio (PBG), um precursor dos tetrapirrólicos (heme, clorofila). Esta enzima é sensível a metais pesados e outros pró-oxidantes e, dessa forma, tem sido classicamente usada como um marcador na intoxicação por chumbo. Estudos in vitro e in vivo têm demonstrado que o organocalcogênio disseleneto de difenila [(P...

  14. Enzimas pécticas de Aspergillus kawachii: aislamiento, purificación y caracterización de pectinesterasa

    OpenAIRE

    Vita, Carolina Elena

    2013-01-01

    Estudiar la producción de enzimas pectolíticas (tanto novedosas como previamente reportadas) por Aspergillus kawachii, caracterizarlas y compararlas con sus equivalentes de otros orígenes. Considerando la capacidad de A. kawachii de producir enzimas activas en condiciones de alta acidez y al escaso conocimiento de su sistema pectolítico, se inició este trabajo de investigación para contribuir al estudio de las pectinasas de este microorganismo. Este trabajo incluyó el screening de actividades...

  15. Development of enzyme-linked immunosorbent assay (ELISA) for glutathione S-transferase (GST-S) protein in the intertidal copepod Tigriopus japonicus and its application for environmental monitoring.

    Science.gov (United States)

    Rhee, Jae-Sung; Kim, Bo-Mi; Jeong, Chang-Bum; Leung, Kenneth Mei Yee; Park, Gyung Soo; Lee, Jae-Seong

    2013-11-01

    To utilize the GST-S protein as a useful biomarker for environmental contamination, we developed a polyclonal antibody-based enzyme-linked immunosorbent assay (ELISA) in the intertidal copepod Tigriopus japonicus. Two polyclonal antibodies, TJ-GST-S1 and TJ-GST-S2, were raised against two TJ-GST-S synthetic peptides. Also a recombinant TJ-GST-S protein was purified as a standard for ELISA development. Each polyclonal antibody was tested by Western blot analysis and indirect ELISA. Of two polyclonal antibodies, TJ-GST-S2 ELISA was further employed due to its wide range of detection and the limit of specificity compared to those of TJ-GST-S1 ELISA system. After exposure to 4 metals (Ag, As, Cd, and Cu) to T. japonicus, the amount of TJ-GST-S protein was significantly elevated in a concentration-dependent manner. Also, TJ-GST-S protein was upregulated at relative high concentrations of B[α]P, PCB, and TBT. In this paper, we suggest that T. japonicas ELISA for TJ-GST-S2 is useful as a potential indicator system for marine contaminants. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Nueve casos del sindrome HELLP (hemolisis, enzimas hepaticas Elevadas y plaquetopenia

    Directory of Open Access Journals (Sweden)

    M. F. Capellino

    2003-10-01

    Full Text Available El síndrome HELLP (hemólisis, enzimas hepáticas elevadas y plaquetopenia descripto por Weinstein en 1982, se asocia a alta morbi-mortalidad materna y perinatal. Se evaluaron retrospectivamente las pacientes que presentaron síndrome HELLP entre marzo 1998 y marzo 2001 en el Hospital Privado de Córdoba. Se identificaron nueve pacientes con Síndrome HELLP (incidencia 2.3‰. La edad media de las pacientes fue 24.5 años (15-36 con una edad gestacional media de 34.5 semanas (29-40. Cinco pacientes fueron nulíparas. El síntoma principal fue epigastralgia (77.7%. El parto fue por cesárea en siete pacientes y tres tuvieron síndrome HELLP post-parto. Tres pacientes presentaron hipertensión de difícil manejo, una eclampsia y otra coagulación intravascular diseminada, insuficiencia renal aguda y muerte. Tres requirieron transfusión de derivados sanguíneos y el promedio de internación fue 4.4 días. Seis (75% neonatos fueron pretérmino. El peso medio de nacimiento fue 2030 gramos (736-3200. Cuatro recién nacidos tuvieron un score de Apgar menor de 7 al minuto y todos mayor de 7 a los cinco minutos. Tres neonatos presentaron trastornos alimentarios, uno hipoglucemia y otro enfermedad de membrana hialina, ductus arterioso permeable, sepsis y plaquetopenia. Debido a la morbi-mortalidad materna y perinatal el síndrome HELLP requiere atención en un centro de alta complejidad mediante un equipo multidisciplinario.HELLP syndrome (Hemolysis, Elevated Liver Enzymes and Low Platelets was described by Weinstein in 1982. It has a high maternal and perinatal morbi-mortality rate. We undertook this study to evaluate perinatal outcome in patients with HELLP syndrome. Patients with HELLP syndrome were identified in a retrospective study between March 1998 and March 2001 at the Hospital Privado de Córdoba. Maternal and neonatal variables were analized. Nine patients with HELLP syndrome were identified (incidence 2.3‰. Mean maternal age was 24.5 (15

  17. EFEITO DE ENZIMAS FIBROLÍTICAS SOBRE A COMPOSIÇÃO BROMATOLÓGICA DE SILAGENS DE CAPINS TROPICAIS

    Directory of Open Access Journals (Sweden)

    Cirano José Ulhoa

    2006-10-01

    Full Text Available Este trabalho foi desenvolvido para determinar o efeito de níveis de enzimas fibrolíticas sobre a composição bromatológica e a degradabilidade ruminal da MS e da FDN das silagens de capim-braquiária e de capim-tanzânia. O experimento consistiu de quatro níveis enzimáticos (0, 5, 10e 20 mg de enzimas por kg de matéria natural e dois períodos de armazenamento (45 e 120 dias e três repetições. Após o armazenamento, os silos experimentais foram abertos para avaliação dos teores da MS, da PB, da FDN, do N-NH3/NT e do pH. Utilizou-se a técnica do saco de náilon,com três bovinos canulados no rúmen, horários de incubação de 6, 24 e 96 horas e amostras do período de 45 dias de ensilagem. Verificou-se que as soluções enzimáticas não alteraram o teor de MS, PB, N-NH3/NT e pH das silagens de capins. Para o capim-braquiária, a solução enzimática alterou o teor da FDN, mas foi dependente do nível de enzimas.Verificou-se redução da FDN para o nível de 20 mg (67,99% em relação ao tratamento-testemunha (70,28%. Não houve diferença entre os períodos de armazenamento nem interação entre período de armazenamento e nível enzimático. Para os parâmetros de degradação ruminal da MS e da FDN das silagens de capins não foram observadas diferenças entre os tratamentos. PALAVRAS-CHAVE: Aditivos, celulases, degradabilidade, hemicelulases, parede celular

  18. Docking molecular de derivados de 2-fenilindano-1,3-dionas inibidores da enzima HMG-CoA

    Directory of Open Access Journals (Sweden)

    R. Q. Pordeus

    2014-11-01

    Full Text Available As doenças cardiovasculares constituem uma das principais causas de mortes em todo o mundo. Estudos mostram que a enzima HMG-CoA é considerada uma precursora da via metabólica hipolipidêmica no soro sanguíneo. Na busca por uma nova classe de compostos aptos a inibir esta enzima e consequentemente reduzir os níveis de colesterol, as 2-fenilindano-1,3-dionas apresentam resultados promissores. Uma das maneiras de avaliar o poder farmacológico destes compostos e predizer análogos ainda mais potentes consiste na avaliação da interação entre fármaco (2-fenilindano-1,3-diona e enzima (HMG-CoA, em que se utiliza da técnica de modelagem molecular docking. Neste estudo, o procedimento computacional para obtenção dos resultados de docking foi feito através do software AutoDock 1.5.6. Para avaliar a interação no sítio ativo da HMG-CoA, utilizamos, dentre a série de congêneres, o composto 2-(2-clorofenilindano-1,3-diona. De acordo com os resultados obtidos, foi identificada uma interação hidrofílica importante, do tipo ligação de hidrogênio C=O∙∙∙H–N, a qual apresenta uma distância de 1.62 Å entre os grupos carbonila do anel diona e o aminoácido metionina da HMG-CoA. Outra ligação de hidrogênio p∙∙∙H–N com distância de 3.10 Å formada entre o anel aromático do grupo indano-1,3-diona e o aminoácido glicina também foi identificada.

  19. Síntesis de las enzimas de piruvato, oxidorreductasa de ferredoxina y deshidrogenasa E de alcohol durante el desenquistamiento (excystacion de Giardia intestinalis

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Niño

    2010-03-01

    Conclusiones. Nuestros resultados muestran de forma concluyente que las enzimas PFOR y ADHE son traducidas en el proceso de desenquistamiento (excystacion y esto demuestra que existe un proceso activo de síntesis de proteínas durante él.

  20. Produção in vitro de enzimas extracelulares por fungos e sua relação com os sintomas descritos em planta hospedeira

    Directory of Open Access Journals (Sweden)

    Alice Elias

    2015-12-01

    Full Text Available RESUMOOs fungos fitopatogênicos habitantes de solo causam perdas econômicas em muitas culturas e são difíceis de serem controlados. Esses fungos podem ser agrupados pelos sintomas comuns que causam nas plantas, bem como pelas enzimas extracelulares que podem produzir. O objetivo do trabalho foi verificar a produção in vitro de enzimas extracelulares por fungos de solo e tentar relacionar essas enzimas com os sintomas que cada fungo causa em planta hospedeira. O ensaio foi delineado em esquema inteiramente casualizado, com dois fatores, sete fungos (Cylindrocladium spathiphylli, Rhizoctonia solani, Sclerotium rolfsii, Ceratocystis fimbriata, Sclerotinia sclerotiorum, Fusarium oxysporum f. sp. dianthi e Verticillium dahliae mais testemunha e seis enzimas (amilase, carboximetilcelulase, lipase, lacase, catalase e gelatinase com 10 repetições. Catalase e gelatinase foram mensuradas por escala de notas, enquanto que as demais pelo cálculo da área da coroa circular. O ensaio foi repetido e a análise foi realizada com os dados de dois ensaios. Os fungos que causam podridão na raiz ou no colo da planta apresentaram maior produção de lacase, enquanto os que causam obstrução, fendas ou até a destruição do sistema vascular demonstraram a prevalência da lipase.

  1. Determinação da energia metabolizável do farelo residual do milho com e sem enzima em dietas para frangos de corte

    Directory of Open Access Journals (Sweden)

    C.G. Valadares

    2016-06-01

    Full Text Available RESUMO O objetivo deste trabalho foi avaliar o valor nutricional e determinar a energia metabolizável do farelo residual de milho (FRM sem e com o uso da enzima alfa- amilase. Foi realizado um experimento de metabolismo com 180 pintos machos Cobb com 14 dias, distribuídos em um delineamento inteiramente ao acaso, com seis tratamentos, cinco repetições e seis aves por parcela. As dietas experimentais foram: T1: ração referência (RR, T2: 60% T1 + 40% de FRM, T3: RR + enzima, T4: 60% T1 + 40% de FRM com adição de enzima, T5: RR com substituição de 100% do milho pelo FRM e T6: RR com substituição de 100% do milho pelo FRM com adição de enzima. A composição química do FRM foi: 88,33% de matéria seca (MS, 10,23% de proteína bruta (PB, 15,44% de extrato etéreo (EE, 4,33% de cinzas (CZ e 4555kcal/kg de energia bruta (EB. Os valores dos coeficientes de metabolizabilidade aparente para o FRM sem e com adição de enzima foram, respectivamente, de 73,37% e 76,33% para MS (p=0,0136, 70,44% e 70,39% para PB (p=0,9595 e de 74,79% e 76,77% para EB (p=0,0128. Os valores da energia metabolizável aparente (EMA e da EMA corrigida para retenção de nitrogênio (EMAn para o FRM (na base natural foram de 3322±19 e 3241±18kcal/kg e de 3334±16 e 3261±17kcal/kg, respectivamente, sem e com adição de enzima. A adição da enzima não teve efeito estatístico significativo sobre os valores de EMA e EMAn, entretanto houve efeito positivo no coeficiente de metabolização da energia.

  2. Enzimas exógenas em dietas de frangos de corte: desempenho Exogenous enzymes in broilers fed diets: performance

    Directory of Open Access Journals (Sweden)

    Nei André Arruda Barbosa

    2012-08-01

    Full Text Available O experimento foi conduzido para avaliar a eficiência de enzimas exógenas em dietas sobre o desempenho de frangos de corte. Um total de 1440 pintos de corte machos (Cobb 500® foram distribuídos em um delineamento inteiramente casualizado em esquema fatorial 2x2 (duas dietas com diferentes densidades nutricionais; com e sem a adição enzimática com 8 repetições de 45 aves em cada unidade experimental. As dietas com diferentes densidades nutricionais foram: controle positivo (níveis normais e um controle negativo (com redução de 4,3 e 4,5% de energia metabolizável; 16,7 e 17,7% de cálcio e 35 e 42,7% de fósforo, nas fases inicial e de crescimento, respectivamente. A suplementação enzimática consistiu da combinação das enzimas fitase (100g t-1 e amilase, xilanase e protease (500g t-1. Foi avaliado o desempenho das aves nas fases de 1 a 21 e 1 a 42 dias de idade. Na fase total de criação, as aves alimentadas com a dieta controle negativo com adição enzimática tiveram consumo de ração (5,97%, peso médio (8,47%, ganho de peso (8,64% e conversão alimentar (2,92% melhores (P0,05 ao grupo alimentado com a dieta controle positivo com ou sem enzima. A adição de enzimas exógenas em dieta de frangos de corte com redução de energia metabolizável, cálcio e fósforo, proporciona um consumo de ração, peso vivo médio e ganho de peso similar a uma dieta com níveis nutricionais adequados.The experiment was conducted to evaluate the effect of enzyme efficiency in diets with and without nutrient reduction on the performance of broilers. Thousand and hundred forty male broiler chicks (Cobb 500® were distributed in a completely randomized design with 4 treatments in a factorial 2x2 (two diets with different nutrient densities, with and without enzyme with 8 replications of 45 birds. The diets were: positive control (normal and a negative control (with a reduction of 4.3% and 4.5% of metabolizable energy, 16.7% and 17.7% of

  3. Efeito tóxico dos praguicidas maneb e paraquat sobre a atividade da enzima antioxidante catalase em ratos

    Directory of Open Access Journals (Sweden)

    M. D. Arbo

    2009-01-01

    Full Text Available

    Os radicais livres estão envolvidos em um grande número de enfermidades do ser humano. O cérebro tem níveis baixos de enzimas antioxidantes e um conteúdo lípidico elevado, tornando-se muito susceptível ao ataque de espécies reativas de oxigênio. Neste trabalho avaliou- se a lipoperoxidação em hipocampo e a atividade da enzima catalase em estriado e hipocampo de ratos tratados com o fungicida maneb (30 mg/kg e o herbicida paraquat (10 mg/kg. Não houve alteração na lipoperoxidação nem na atividade enzimática no hipocampo dos animais tratados com ambos os praguicidas, porém foi observada uma inibição da catalase no estriado dos ratos tratados com maneb e com paraquat. Com estes resultados pode-se sugerir, de forma preliminar, uma ação tóxica maior sobre centros dopaminérgicos. Estudos sobre a toxicidade destes compostos são essenciais na compreensão do papel destes praguicidas e dos radicais livres na etiologia das doenças. Palavras-chave: catalase; paraquat; maneb; estriado; hipocampo; radicais livres.

  4. Associação do polimorfismo do gene da enzima conversora da angiotensina com dados ecocardiográficos em jovens normotensos filhos de hipertensos

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    Franken Roberto Alexandre

    2004-01-01

    Full Text Available OBJETIVOS: Os autores objetivaram no presente estudo avaliar o polimorfismo da enzima conversora da angiotensina com dados do ecocardiograma de jovens estudantes de Medicina, filhos de hipertensos, comparados com jovens filhos de normotensos. MÉTODOS: Foram estudados 80 jovens normotensos divididos em dois grupos: 40 filhos normotensos de pais hipertensos e 40 filhos normotensos de pais hipertensos. Critérios de exclusão foram hipertensão arterial, fumo, obesidade, uso de contraceptivos orais. Uso crônico de medicamentos e presença de qualquer doença. Os alunos foram incluídos entre 1994 e 1996. Cinqüenta alunos foram submetidos a ecocardiograma transtoráxico. A análise estatística foi feita através do teste T de Student. A avaliação do polimorfismo do gene da enzima conversora da angiotensina foi feita nos 80 alunos conforme segue: 1 5 ml de sangue em tubo contendo EDTA, 2 extração do DNA, 3 medida da concentração do DNA por eletroforese, 4 reação em cadeia de polimerase com ''primer'' do gene da enzima conversora da angiotensina, 5 análise do polimorfismo do gene da enzima conversora da angiotensina através da eletroforese e 6 análise estatística através do teste do Qui-quadrado. RESULTADOS: O grupo de estudantes filhos de hipertensos mostraram maior espessura do septo interventricular (7,82mm+/-0,69 contra 7,38 +/- 0,8, p 7,82mm; DD 32%, DI 24%, II 20% contra septo 7,38mm: DD28%, DI12%, II 12%, contra septo 131,52g: DD 20,69% DI 13,79%, II 6,9% contra massa 117,11g: DD 30,43%, DI 8,7%, II 8,7% contra massa < 117,11g: DD 13,04%, DI 21,74%, II 17,39% (p=0,17 CONCLUSÃO: Encontramos diferenças entre a espessura do septo interventricular de estudantes normotensos filhos de hipertensos e filhos de normotensos. Por outro lado, não encontramos diferenças entre os grupos considerando o polimorfismo do gene da enzima de conversão da angiotensina, assim como qualquer relação do gene da enzima de conversão da

  5. Enzimas amilolíticas de mandioquinha-salsa (Arracacia xanthorrhiza Bancroft. Amylolytic enzymes from peruvian carrot (Arracaia xanthorrhiza Bancroft.

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    Tatiana da Costa Raposo Pires

    2002-12-01

    Full Text Available O objetivo do presente trabalho foi de caracterizar as enzimas amilolíticas de mandioquinha-salsa (Arracacia xanthorrhiza Bancroft.. Foram realizados ensaios mediante a determinação da atividade enzimática, variando-se as condições do meio, tais como temperatura, pH e concentração de cátions. Em gel de eletroforese foram detectadas três bandas protéicas com intensa atividade hidrolítica. As enzimas apresentaram pH ótimo de atividade em torno de 6,0 e mostraram-se mais sensíveis a valores de pH alcalino quando pré-incubadas a 50oC. A temperatura ótima de ativação enzimática foi de 50oC, enquanto aos 70oC, a atividade amilásica foi reduzida em 80%. Em temperaturas altas temperaturas (60 e 70oC, a inativação enzimática ocorreu após 60 e 25min de incubação, respectivamente. Ensaios de estabilidade térmica mostraram que as amilases mantiveram alta atividade após 25h mediante a incubação a 20 e 30oC. Os valores de Km, Vmax e energia de ativação foram de 0,41mg/mL, 1,11mg/mL/min e 7,53kcal/mol, respectivamente. Constatou-se que a presença de Ca+2 ou Mg+2 provoca aumento na atividade amilásica, enquanto íons de Cu+2 causam uma diminuição. Apesar da discreta atividade amilásica apresentada, as enzimas demonstraram ter alta resistência e estabilidade térmicas.This investigation was undertaken to characterize amylases from Peruvian carrot (Arracacia xanthorrhiza Bancroft.. Activity assays were performed in different changing pHs, temperatures, time and cation concentrations. PAGE zymograms and the amylase activity essays were detected by starch-iodine complex. The results showed that Peruvian carrot has three amylase components on the crude extract. The enzymes had optimum pH at 6.0. Amylases were more sensitive to basic pH when the pre-incubation occured at 50oC. The best activation temperature occurred at 50oC, whereas at 70oC the amylase activity was reduced by 80%. Assays of thermal stability at 20 and 30o

  6. INDUCCIÓN DE LA ACTIVIDAD DE LA ENZIMA FENILALANINA AMONIO LIASA EN CLAVEL (Dianthus caryophyllus L POR ELICITORES DEL HONGO Fusarium oxysporum f. sp. Dianthi raza 2

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    Harold Ardila

    2008-04-01

    Full Text Available Con el fin de evaluar el comportamiento a nivel del tallo de la enzima fenilalanina amonio liasa (PAL, por su nombre en inglés phenylalanine ammonia liase, durante la interacción clavel-Fusarium oxysporum f. sp. dianthi raza 2, se seleccionaron las condiciones para su extracción y cuantificación de la actividad. Para la extracción a partir de tallos y raíces se seleccionó un tratamiento previo del material vegetal con acetona y posterior extracción con buffer borato pH 8,8 con EDTA 2mMy -mercaptoetanol 18 mM. Para su cuantificación a nivel del tallo se debe realizar un ensayo discontinuo por 10 min, a 37 oC, pH 8,0 y a una concentración de sustrato de 35 mM. Adicionalmente se muestra mediante un ensayo in vivo el efecto que tiene, como inductor de esta enzima, la aplicación de un extracto crudo del patógeno. Los resultados observados indican que esta enzima se induce significativamente en tallos de claveles de la variedad tolerante “Kiss” durante el tratamiento por aspersión con el extracto crudo del patógeno, mientras que dicha inducción fue inexistente para la infección directamente con el patógeno. La inducción en esta variedad indica que en este extracto del patógeno se presentan elicitores potenciales para la inducción de esta enzima y por ende de la ruta fenilpropanoide.

  7. Correlação entre a incapacidade funcional, idade e enzimas séricas nas doenças neuromusculares

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    Lineu Cesar Werneck

    1995-03-01

    Full Text Available Foram estudados 806 casos de diversas doenças neuromusculares, a fim de verificar se existe correlação entre o grau de incapacidade funcional aferida pela escala de Vignos e Archibald (V&A e enzimas séricas (creatinoquinase, desidrogenase lática, aldolase, transaminase glutâmica oxalacética e pirúvica. Foram utilizados testes para a análise do coeficiente de correlação simples (Pearson e múltiplo. Foi encontrada correlação positiva (piora progressiva da incapacidade da V&A com a idade em algumas doenças, como a distrofia muscular de Duchenne, distrofia fascio-escapulo-umeral, distrofia miotônica, miopatias com defeitos enzimáticos da cadeia respiratória e esclerose lateral amiotrófica. Por outro lado, foi detectada correlação negativa (melhora progressiva dos sintomas na miopatia do multicore, miopatia benigna da infância com predomínio de fibras do tipo 1, deficiência de carnitina e dermatomiosite. A V&A mostrou maiores correlações (p< 0,05 entre as diversas enzimas sérícas quando estudadas isoladamente na distrofia muscular de Duchenne, distrofia óculo-crânio-somática, polimiositcs e periarterite nodosa. Quando as enzimas foram analisadas em conjunto, através de teste de correlação múltipla, verificou-se pequena correlação entre elas e a V&A. Esta reduzida interrelação sugere que a utilização de diversas enzimas na análise longitudinal das doenças neuromusculares é limitada, não tendo aplicação pratica, embora sejam muito importantes no diagnóstico.

  8. Produção de enzimas extracelulares por fungos associados à decomposição materiais vegetais em riachos

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    Jéssica Barros Aguiar Silva

    2015-12-01

    Full Text Available As celulases e xilanases fúngicas, derivadas de sua habilidade degradativa e excretadas, em geral, para o meio, despertam interesse biotecnológico por terem um largo espectro de aplicação. Objetivou-se verificar a produção das enzimas celulase e xilanase por fungos filamentosos isolados de detritos foliares alóctone em um córrego no Cerrado. Os testes foram realizados com 100 cepas utilizando meio de cultura sintético contendo, como única fonte de carbono, carboximetilcelulose e xilana, para celulase e xilanase, respectivamente. Foram realizados inóculos no centro das placas e armazenadas por 4 dias em BOD a 28°C e submetido a choque térmico em estufa a 50°C por 16 horas. Para melhor visualização do halo de hidrólise as placas foram coradas com solução de vermelho congo e lavadas com solução de NaCl. Dos fungos testados 69% apresentaram resultado positivo para celulase dos quais 23% foram consideramos com potencial para aplicação em biotecnologia. Não houve resultados positivos para a produção da enzima xilanase. Os fungos testados, associados ao processo de decomposição de matéria orgânica vegetal, apresentaram produção da enzima celulase, mas não da enzima xilanase.

  9. Evaluación de la actividad de la enzima citocromo P-450 1A2 en una población colombiana

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    Fanny Cuesta González

    2000-02-01

    Full Text Available

    Introducción: La enzima citocromo P450 1A2 (CYP1A2, presente en tejidos hepáticos humanos, participa en el metabolismo de fármacos tales como Clozapina, Imipramina, Teofilina y Cafeína. Estudios realizados en diferentes poblaciones han mostrado una distribución bimodal y a veces trimodal en la actividad de esta enzima. Este comportamiento ha sido relacionado con variaciones tanto del gen codificante como de las regiones reguladoras, aunque hasta el momento los resultados no son concluyentes. Además del metabolismo de fármacos, la CYP1A2 interviene en la activación de sustancias procarcinogénicas tales como N-nitrosaminas, aminas heterocíclicas y aromáticas; es conocida la correlación entre una actividad incrementada de esta enzima (metabolizadores rápidos con una mayor exposición al riesgo de cáncer.

    Debido a la baja incidencia de efectos secundarios y la facilidad en la medición de los metabolitos en orina, la Cafeína es utilizada como fármaco prueba para la determinación de la actividad enzimática CYP1A2, calculando la relación entre las concentraciones molares de sus metabolitos (Actividad CYP1A2 = AFMU+MU+MX/17DMU.

    En el presente estudio se evaluará la actividad de la enzima CYP1A2 en una muestra de individuos sanos, con el fin de describir su comportamiento y compararlo con el encontrado en otras poblaciones, las cuales tienen una influencia genética y ambiental diferente a la de la población colombiana.

    Metodología: Una vez recolectadas las muestras de orina, se separarán de ellas los

  10. USO DE NANOPARTÍCULAS DO MESOCARPO DO BABAÇU COMO PLATAFORMA PARA ANCORAGEM DE ENZIMAS NO DESENVOLVIMENTO DE BIOSSENSORES: UM MAPEAMENTO TECNOLÓGICO

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    Ana Siqueira do Nascimento Marreiro Teixeira

    2018-03-01

    Full Text Available A imobilização de enzimas na construção de biossensores torna-se atraente pela capacidade enzimática de catalisar com grande eficiência, reações biológicas com alta sensibilidade e seletividade. A utilização de materiais nanoestruturados, tais como nanopartículas poliméricas, surge como alternativa para aumentar a eficiência da imobilização de enzimas. Dessa forma, surge o interesse na síntese de nanopartículas do mesocarpo do babaçu (Orbignya phalerata Mart, por se tratar de um biopolímero natural, atóxico, facilmente encontrado na região nordeste do País. Diante do relatado, o presente trabalho propõe um estudo prospectivo a respeito do desenvolvimento de um biossensor contendo a enzima polifenol oxidase como monocamada imobilizada, pela técnica de automontagem, sobre a superfície de nanoparticulas poliméricas geradas a partir do mesocarpo de babaçu para detecção de sulfitos em produtos alimentícios, visto que tais compostos são causadores de reações alérgicas em indivíduos que apresentam sensibilidade a este conservante. Para o mapeamento científico e tecnológico, foram realizadas buscas nas bases de periódicos Web of Science, Scopus e Scielo, e nos bancos de patentes INPI, Espacenet e USPTO, para todas patentes depositadas, e artigos publicados no período de 2005 a agosto 2016. A partir dos artigos e patentes analisados, constatou-se que os estudos relacionados ao mesocarpo de babaçu são escassos, sendo que o desenvolvimento de um biossensor para detecção de sulfito a base de nanopartículas poliméricas deste biopolímero como plataforma para a imobilização da enzima polifenol oxidase para pode ser bastante inovador, visto que não foram encontrados relatos na literatura com abordagem parecida.

  11. Relación de la homocisteína y las enzimas involucradas en su metabolismo con enfermedad cardiovascular y otras patologías.

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    Natalia Arias Morales

    2016-06-01

    Full Text Available Introducción: La homocisteína (HCY en la actualidad tiende a considerarse como un posible marcador temprano del desarrollo de diversas enfermedades, en especial de tipo cardiovascular. Los niveles aumentados de HCY (o hiperhomocisteinemia, hHCY también se han asociado con enfermedades neurológicas, neonatales, neoplásicas, metabólicas, entre otras. La hHCY puede ser consecuencia de diferentes factores como el estado nutricional, la edad, el género y por alteraciones genéticas de las enzimas que participan en su metabolismo. La identificación precoz de los polimorfismos genéticos permitiría establecer un esquema de prevención y tratamiento temprano para evitar la evolución de las patologías previamente enunciadas. Objetivo: Realizar una revisión documental descriptiva sobre la relación de la HCY y enzimas involucradas en su metabolismo con enfermedad cardiovascular (ECV y otras patologías. Materiales y métodos: La presente investigación fue de tipo análisis documental. La muestra de estudio correspondió a literatura científica incluida en bases de datos como Springer, PubMed, Scielo, Wiley y material bibliográfico documental relacionada con la homocisteína, enzimas involucradas en su metabolismo, así como su posible asociación con ECV y otras patologías, incluyéndose 140 fuentes bibliográficas. Para el análisis de la información recolectada se utilizó estadística básica descriptiva. Resultados: Del total de fuentes consultadas, predominaron artículos científicos en inglés con fecha de publicación entre 2005 y 2015. De los documentos revisados se evidenció que los países con mayor número de publicaciones fueron Estados Unidos (19%, España (9%, India (7%, China (7%, Brasil (7%, México (5%, Egipto (4%, Colombia (4%, entre otros. En mayor cantidad se encontraron artículos basados en la genética de la HCY, seguidos de causas de hHCY, patologías asociadas, metabolismo, bioquímica, diagnóstico y reportes

  12. Purificación y caracterización parcial de la enzima xilanasa a partir del preparado comercial Novoban 240

    OpenAIRE

    Dalila Paz-Lago; Marta Hernández

    2000-01-01

    Novoban 240 es un preparado enzimático comercial de la Novo Industri con actividad amilasa, que se obtiene por fermentación sumergida de Bacillus amilolichuefaciens y es utilizado en la industria de elaboración de vinos. Este preparado de uso industrial posee actividad xilanasa, enzima estrechamente relacionada con la respuesta hipersensible de los tejidos vegetales frente al ataque de microorganismos patógenos. En el presente trabajo se establece una metodología de purificación parcial de es...

  13. Caracterización de las enzimas esterasas implicadas en la interacción polen-pistilo en el olivo (Olea Europaea L.)

    OpenAIRE

    Rejón García, Juan David

    2013-01-01

    El éxito de la fertilización en las Angiospermas depende en gran medida de la capacidad del polen para germinar y emitir un tubo polínico, el cuál transporta los núcleos espermáticos a través del pistilo hasta el saco embrionario. En este contexto, los objetivos de este proyecto fueron: 1) determinar la existencia de actividad esterolítica en el polen de olivo, 2) identificar y clasificar desde el punto de vista funcional las distintas enzimas esterasas, 3) determinar las funciones del exudad...

  14. Efeito de enzimas hidrolíticas no comportamento reológico do óleo de palma cru

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    FREITAS Suely P.

    1998-01-01

    Full Text Available No processamento tradicional de extração de óleo de palma, uma quantidade substancial do produto é perdida na fibra - durante a etapa de prensagem do fruto - e na borra - durante a etapa de clarificação do óleo cru. A viscosidade deste constitui a principal dificuldade de separação do óleo dos demais componentes da mistura. A eficiência de recuperação do óleo é usualmente melhorada por adição de água, no tanque de clarificação. Neste trabalho avaliou-se os efeitos da diluição e do tratamento enzimático no comportamento reológico do óleo de palma cru. Estes dados são importantes para estimar a velocidade de separação do óleo nos tanques de clarificação e/ou nos decanters das usinas comerciais. O óleo cru utilizado neste estudo foi recolhido em uma unidade comercial sendo composto de 65% de água, 30% de óleo e 5% de sólidos. A hidrólise enzimática foi conduzida usando como agentes hidrolisantes uma enzima comercial (viscozyme da Novo Nordisk e um preparado enzimático produzido no CTAA. Pode-se constatar que quanto mais diluída a amostra maior é a redução na viscosidade após a hidrólise enzimática. Para uma taxa de deformação fixa em 6s-1, o tratamento enzimático do óleo cru a 60°C reduziu a viscosidade do mesmo em cerca de 29% enquanto a adição de 20% de água em cerca de 35%. A combinação da diluição com 20% de água seguida de tratamento enzimático reduziu a viscosidade do óleo cru em cerca de 75%.

  15. OBTENÇÃO E UTILIZAÇÃO DA ENZIMA POLIFENOLOXIDASE EXTRAÍDA DE POLPA DE PINHA (Annona squamosa L.) MADURA NO MELHORAMENTO DO SABOR DO CACAU (Theobroma cacao L.)

    OpenAIRE

    LIMA,ELIZA DOROTEA POZZOBON DE ALBUQUERQUE; PASTORE,GLÁUCIA MARIA; BARBERY,SANDRA DRINA FERNANDEZ; GARCIA,NELSON HORÁCIO PEZOA; BRITO,EDY SOUSA DE; LIMA,CARLOS ALBERTO DE ALBUQUERQUE

    2001-01-01

    O presente trabalho teve como objetivo estudar a obtenção e a utilização da enzima polifenoloxidase (PPO) extraída de polpa de pinha madura na redução do teor de compostos polifenólicos com a finalidade de diminuir a adstringência e o amargor das amêndoas de cacau processadas na forma de "nibs". A PPO foi extraída com tampão fosfato de potássio 0,025M (pH 7,5), adicionando sulfato de amônio para a precipitação da enzima. O material em pó obtido foi denominado de enzima parcialmente purificada...

  16. Expresión diferencial de los genes de algunas enzimas lignocelulolíticas en biopelículas de Aspergillus niger

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    Gretty K. Villena

    2008-12-01

    Full Text Available Se realizó una evaluación génica preliminar a nivel transcripcional de biopelículas de Aspergillus niger ATCC 10864 desarrolladas sobre poliéster respecto a algunas enzimas lignocelulolíticas. El análisis de expresión de genes de enzimas lignocelulolíticas y genes reguladores mediante RT-PCR mostró que los genes eng1, eglC, exo y eglA, eglB y xynB son diferencialmente expresados ya sea temporalmente o mediante más de un transcripto en comparación con cultivos sumergidos. Asimismo, los genes reguladores xlnR y creA mostraron patrones temporales de expresión distintos en ambos sistemas. Los resultados obtenidos aportan la evidencia molecular inicial de expresión diferencial de genes en biopelículas así como patrones de regulación diferencial muy probablemente ligada a la adhesión celular.

  17. Efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes em frangos de corte de 1 a 21 dias de idade

    OpenAIRE

    Leite, José Laureano Barbosa; Rodrigues, Paulo Borges; Fialho, Elias Tadeu; Freitas, Rilke Tadeu Fonseca de; Nagata, Adriano Kaneo; Cantarelli, Vinícius de Souza

    2008-01-01

    Conduziu-se este experimento para avaliar o efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes, em frangos de corte de 1 a 21 dias de idade. Foram utilizados 350 pintos de corte, COBB, machos, com peso inicial médio de 47g ± 2,5g, em um delineamento inteiramente casualizado, com os tratamentos em arranjos fatorial 3 x 2 (três dietas, com e sem enzimas) sendo que as dietas consistiram de uma ração farelada e duas rações peletizadas...

  18. Physiological quality and amylase enzyme expression in maize seeds Qualidade fisiológica e expressão das enzimas amilases em sementes de milho

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    Gustavo Evangelista Oliveira

    2013-02-01

    Full Text Available The physiological quality of maize seeds is affected by the genotype. Thus, the study of expression of genes associated with this characteristic is important in the genotype selection process in breeding programs. The aim of this research was to study the expression of amylase enzymes associated with physiological quality of maize seeds with different genotypes and seed sizes. We further sought to assess the expression of these enzymes in dry and soaked seeds The experiment was conducted in the experimental area and the Central Seed Laboratory of the Department of Agriculture of the Universidade Federal de Lavras. Seeds of four maize inbred lines were used, classified in two sizes. The physiological quality of the seeds was evaluated by means of germination, seedling emergence, seedling emergence speed index and accelerated aging test. Expression of the alpha amylase enzyme was evaluated by the electrophoresis technique and expression of the alpha amylase B73, alpha amylase (LOC542522 and beta amylase 5 (amyb5 genes was studied by the qRT-PCR technique in dry and soaked seeds of the inbred lines. There is differentiated expression of amylase enzymes in maize seeds of inbred lines with different levels of physiological quality. higher expression of amylase enzymes is observed in soaked maize seeds. The expression of transcripts is higher in smaller as wellas in soaked maize seeds of inbred lines.A qualidade fisiológica de sementes de milho é influenciada pelo genótipo. Assim, o estudo da expressão de genes associados a essa característica é importante no processo de seleção de genótipos em programas de melhoramento. O objetivo neste trabalho foi estudar a expressão das enzimas amilases associadas à qualidade fisiológica de sementes de milho, de diferentes genótipos e tamanhos de sementes. Objetivou-se ainda avaliar a expressão dessas enzimas em sementes secas e embebidas. O experimento foi conduzido em área experimental e no

  19. Uso de enzimas na alimentação de frangos de corte Enzymes in the broiler diets

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    Evani Souza de Oliveira Strada

    2005-12-01

    Full Text Available Dois experimentos foram realizados para se avaliar o efeito de enzimas microbianas sobre o ganho de peso, o consumo de ração e a conversão alimentar frangos de corte. No primeiro experimento, utilizaram-se 288 pintos de 8 a 21 dias de idade em um delineamento inteiramente casualizado (DIC, em arranjo fatorial 2 x 2, (duas dietas, farelo de soja + sorgo e farelo de soja + milheto, com ou sem complexo multienzimático - CM, com quatro repetições por tratamento, em que cada parcela foi constituída por 18 aves. As dietas foram formuladas para conter níveis idênticos de energia metabolizável (EM, aminoácidos, cálcio e fósforo. No segundo experimento, foram utilizados 384 frangos de corte de 21 a 42 dias de idade em delineamento inteiramente casualizado, com seis tratamentos, quatro repetições e 16 aves por unidade experimental. As dietas experimentais, à base de milho e farelo de soja, foram formuladas para conterem 7 e 9% de EM e 5 e 7% dos aminoácidos metionina (Met, Met + cistina (Cis e lisina (Lis, com a presença ou não de complexo multienzimático. A inclusão do CM, tanto em rações à base de farelo de soja e sorgo como à base de farelo de soja e milheto, não proporcionou ganhos nos desempenhos das aves na fase inicial de crescimento. Os valores de EM e de aminoácidos (Met, Met+Cis e Lis da soja podem ser superestimados em 9 e 7%, respectivamente, quando há adição de CM às rações, sem prejuízo ao desempenho das aves.Two experiments were conducted to evaluate the effects of microbial enzymes on weight gain, feed intake and feed: gain ratio. In the first trial, 288 chicks from 8-21 days old were assigned to a complete randomized design with a 2 x 2 fatorial arrangement: meal (soybean meal + sorghum and soybean meal + millet and with or without multi-enzymatic complex (MC, with four replications of 18 bird per experimental unit. Diets were formulated to contain the same levels of metabolizable energy (ME, amino acids

  20. EVALUACIÓN DE ENZIMAS PARA LA HIDRÓLISIS DE RESIDUOS (HOJAS Y COGOLLOS DE LA COSECHA CAÑA DE AZÚCAR

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    JAIRO G. SALCEDO M.

    2011-01-01

    Full Text Available El presente trabajo tuvo como objetivo la evaluación de la hidrólisis enzimática de residuos de la cosecha de la caña de azúcar (hojas y cogollos a partir de la preparación de cuatro sustratos con diferentes pretratamientos, entre los que se encuentran: delignificación organosolvente, delignificación enzimática, delignificación con hidróxido de sodio y clorito de sodio y un sustrato base obtenido directamente de la cosecha. Además, se elaboraron cinco enzimas a partir de mezclas de actividades de enzimas comerciales, que fueron evaluadas en los diferentes sustratos. Se introduce un criterio para evaluar la eficiencia de las enzimas a partir de curvas de progreso, porcentaje de sacarificación e índice de sacarificación, a este índice se le denomino "índice global de hidrólisis". Los resultados muestran, que para la hidrólisis con el preparado enzimático E5, que contiene las siguientes actividades enzimáticas: hemicelulusas de 52.75 unidades globales/ml, celulasas total de 27.53 FPU/ml, endoglucanasas de 1782,1 CMC/ml, exoglucanasa de 0.377 UI/ml, betaglucosidasa de 550 pNPG U/ml, xilanasa de 28.23 UI/ml, galactosidasa de 7.1 UI/ml, manasa de 2.76 UI/ml y ranmanasa de 14.63 UI/ml y el sustrato S3, con un contenido de celulosa de 80.53%, hemicelulosa de 13.35, lignina 1.36 y un número de Kappa de 5.85 presenta el mayor índice global de Nhidrólisis que corresponde a un valor de 117.16. El estudio permite concluir que el preparado enzimático E5 presenta un gran potencial para la hidrólisis de los residuos de la caña de azúcar tratados en este proyecto.

  1. Enzimas carboidrases na dieta de porcas lactantes e suas leitegadas Carbohydrase enzymes in diets for lactating sows and their litters

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    Débora Cristina Nichelle Lopes

    2009-12-01

    Full Text Available O experimento foi realizado para se avaliar o uso de um complexo enzimático (CE contendo carboidrases na dieta de porcas lactantes e de suas leitegadas. Foram utilizadas 264 fêmeas cruzadas geneticamente homogêneas, que foram bloqueadas pela ordem de parto e distribuídas ao acaso em quatro tratamentos, resultantes de um arranjo fatorial 2x2 (dieta lactação (DL x dieta pré-inicial (DPI, com dois níveis cada fator (com e sem CE. Nas porcas, foram avaliados: peso ao desmame (PDESM; variação do peso corporal; espessura de toucinho (ET; variação de ET; escore corporal (EC; consumo de ração (CRF e composição do leite e nas leitegadas: consumo de ração (CRL; peso da leitegada ao nascer e ao desmame (PLDESM; e peso médio do leitão ao desmame (PMLDESM. Não houve interação significativa entre DL e DPI para nenhuma variável resposta. O PDESM, a ET, a variação de ET, o EC e a composição do leite (teores de gordura, proteína bruta, lactose e matéria seca das porcas não foram influenciados (P>0,10 pela adição de enzimas na DL e na DPI. O CRF e o CRL não foram influenciados (P>0,10 pelos tratamentos. O PLDESM e o PLMDESM foram significativamente maiores quando as porcas receberam DL suplementada com CE, em comparação àquelas que não receberam CE na dieta (74,6 vs 72,9kg e 6,32 vs 6,47kg, respectivamente. Houve um aumento de 1,7kg no PLDESM e de 0,15kg no PLMDESM (P=0,06 e P=0,07, respectivamente, resultando em um incremento estimado de 2,27kg de peso vivo quando os animais chegam ao peso de abate. Porcas alimentadas com rações suplementadas com complexo enzimático contendo carboidrases apresentam leitegadas mais pesadas ao desmame.This research was conducted to evaluate the effect of adding enzymatic complex (EC containing carbohydrases to diets for lactating sows and their litters. A total of 264 genetically homogeneous crossbred sows were used. They were blocked by farrowing order and randomly allotted to four

  2. Hidrólisis del aceite de coco (Cocos nucífera L mediante enzimas estereoespecíficas y sin especificidad posicional.

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    Rodríguez, R.

    1997-02-01

    saponification, is also discussed.

    El aceite de coco, por su composición, aporta a la dieta principalmente ácidos grasos de cadena corta y media, los que desde el punto de vista nutricional tienen ventajas, debido a su rápida utilización metabólica que permite brindar energía, principalmente a nivel hepático. Es importante contar con procedimientos que permitan obtener estos ácidos grasos en forma libre a partir del aceite de coco, ya que de esta manera pueden ser utilizados con diferentes fines, ya sea nutricionales, farmacológicos o tecnológicos. En el presente trabajo se estudió la hidrólisis del aceite de coco producida por dos tipos de lipasas; una lipasa sin especificidad posicional obtenida de Candida cylindracea, y otra lipasa sn-1',3' estereoespecífica, obtenida de Mucor miehei, en forma libre e inmovilizada (Lipozyme IM-20. La lipasa de Candida cylindracea hidroliza un 85%-90% de los triacilgliceroles del aceite a las 47-50 horas de acción. La composición del hidrolizado es muy similar a la del aceite, y en los monoacilgliceroles remanentes la composición de ácidos grasos es poco definida, aunque predominan los de cadena corta (C6 y C8 y media (C10-C14. La enzima de Mucor miehei permite alcanzar sólo un 65% de hidrólisis, que se obtiene a las 30 horas en el caso de la enzima libre y a las 10 horas en el caso de la enzima inmovilizada (Lipozyme IM-20. La composición de ácidos grasos del hidrolizado es muy similar en ambos casos, destacando la presencia de ácidos grasos en el rango C8-C14, aunque con una composición muy diferente a la del aceite original. La composición de ácidos grasos del monoacilglicerol remanente muestra una marcada predominancia de ácido láurico (C12:0 en el producto de ambas formas de la enzima, lo cual indicaría que este ácido graso ocupa mayoritariamente la posición sn-2' de los triacilgliceroles del aceite de coco. Se discute la utilidad de las lipasas para obtener fracciones

  3. EFECTO DE LA GLUCOSA Y NITRATO DE AMONIO SOBRE LAS ENZIMAS LIGNINOLÍTICAS PRODUCIDAS POR Trametes versicolor INMOVILIZADO EN ESPUMA Y LA DECOLORACIÓN DE UN EFLUENTE PAPELERO EN UN BIORREACTOR DE LECHO FLUIDIZADO

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    M. Martínez-Salgado

    2005-12-01

    Full Text Available En Colombia se han realizado varios estudios para el tratamiento de aguas residuales de la industria papelera a escala de laboratorio, con el hongo Trametes versicolor inmovilizado en espuma de poliuretano; este hongo ha sido ampliamente estudiado por la producción de enzimas ligninolíticas y su potencial uso en la decoloración de efluentes. En este trabajo, se estudió el efecto de una fuente de carbono (glucosa y una de nitrógeno (nitrato de amonio en un biorreactor de lecho fluidizado, con adición al medio de cultivo de 0.02% (v/v de Tween 80, 12 ppm de MnSO4 y 1 mM de CuSO4, desarrollando un diseño factorial 22 con dos diferentes concentraciones de los nutrientes, siendo éstos las variables independientes y las variables dependientes fueron la actividad enzimática, las unidades de color y el consumo de sustrato los cuales fueron determinados por métodos colorimétricos, además de la biomasa y pH. El uso del biorreactor de lecho fluidizado con entrada de aire constante, arrojó datos importantes sobre la decoloracióny la producción de enzimas en el agua residual no estéril. Los máximos valores de la enzima Mnperoxidasa fueron hallados en las concentraciones altas y bajas de glucosa y nitrato de amonio con valores de 9.257U y 6.502U; para la enzima Lacasa, al adicionar separadamente las dos variables se obtuvo valores de 8.618U y 8.341U. Las enzimas fueron relacionadas con la disminución de las unidades de color hasta 481.06UC, junto con el aumento de la biomasa del hongo Trametes versicolor hasta 3.365 g junto con flora nativa del agua residual. Los resultados encontrados, determinaron que las variables de consumo de sustrato y biomasa, tienen una gran importancia debido a que el aumento de la biomasa genera un aumento en la actividad de la enzima MnP y en la reducción de las unidades de color.

  4. Digestibilidad in situ de dietas con harina de nopal deshidratado conteniendo un preparado de enzimas fibrolíticas exógenas In situ digestibility in dehydrated ground prickly pear diets containing a fybrolitic enzymes product

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    Marco Medina Romo

    2006-07-01

    Full Text Available Se evaluó el efecto de un preparado de enzimas fibrolíticas exógenas (celulasas y xilanasas en la degradabilidad in situ de la materia seca (DisMS, fibra detergente neutro (DFDNr y fibra detergente ácido residual (DFDAr, en dietas altas o bajas en harina de nopal deshidratado. Se aplicaron concentraciones de 0, 1, 2 y 3 g de enzima por kilogramo de materia seca al inicio y 24 horas antes de la degradación in situ. Se determinó la concentración de ácidos grasos volátiles totales y de nitrógeno amoniacal a las 0, 3, 6, 9, 12 y 24 horas después de aplicarse la enzima. No se observaron efectos en DisMS, DFDNr y DFDAr; la aplicación al inicio de la degradación in situ mostró valores más altos que a 24 horas para DisMS y DFDNr, pero fue menor para DFDAr. No se observaron diferencias en las interacciones entre niveles de enzima, tipo de dieta y tiempo de pretratamiento. La aplicación de 1 y 3 g de enzima, en la dieta con bajo contenido de harina de nopal, tuvo efectos en el incremento de los ácidos grasos volátiles totales; para el nitrógeno amoniacal, los mejores resultados ocurrieron con 0 y 1 g de enzima.It was evaluated the effect of a fybrolitic enzyme product (cellulases and xylanases on in situ digestibility of dry matter (DisMS, residual neutral detergent fiber (DFDNr and acid detergent fiber (DFDAr, in dehydrated ground prickly pear diets with a low or high level. Enzyme concentrations of 0, 1, 2, and 3 g kg-1 of dry matter applied at the beginning (0 hour and 24 hours before starting in situ digestibility were used. Total volatile fatty acids and ammonia nitrogen were determined at: 0, 3, 6, 9, 12, and 24 hours after the enzyme application. There were no effects on DisMS, DFDNr, and DFDAr. Initial application of enzyme concentrations (0 hour was higher than 24 hours for DisMS and DFDNr but lower for DFDAr. No differences were observed in interactions among enzyme level, diet and application time. Application of 1 and 3 g of

  5. Enzyme expression in indica and japonica rice cultivars under saline stress=Expressão de enzimas em cultivares de arroz indica e japonica sob estresse salino

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    Cristina Rodrigues Mendes

    2012-10-01

    indicas amplamente utilizadas no RS demonstram maior suscetibilidade à salinidade quando comparadas às japonicas em outros aspectos fisiológicos. O objetivo da pesquisa foi analisar a expressão de enzimas envolvidas na respiração de cultivares de arroz, indica e japonica, submetidas à salinidade. Foram utilizadas cultivares de Oryza sativa L. spp. japonica S. Kato (BRS Bojuru, IAS 12-9 Formosa e Goyakuman e de Oryza sativa L. spp. indica S. Kato (BRS-7 Taim, BRS Querência e BRS Atalanta. As plântulas foram transferidas para bacias de 15 L, contendo solução nutritiva de Hoagland meia força acrescida de 0, 25, 50, 75 e 100 mM de NaCl. A coleta foi aos 14, 28 e 42 dias. Os tecidos vegetais foram macerados e colocados em tubos eppendorf com solução extratora de Scandálios. A eletroforese foi realizada em géis de poliacrilamida 7% em cubas eletroforéticas verticais. As bandas foram reveladas para os sistemas enzimáticos esterase, álcool desidrogenase, fosfoglico isomerase, malato desidrogenase, enzima málica e alfa amilase. A expressão das enzimas foi maior na subespécie japonica, com bandas mais intensas conforme o aumento da salinidade. Conclui-se que tais sistemas enzimáticos estejam envolvidos em mecanismos de tolerância ao estresse salino nas cultivares de O. sativa spp. japonica.

  6. Phytase enzyme in diets containing defatted rice bran for growing swine Enzima fitase dietas com farelo de arroz desengordurado para suínos em crescimento

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    José Aparecido Moreira

    2003-12-01

    Full Text Available Organic phosphorus is poorly utilized by monogastric animals because they lack phytase, the enzyme that cleaves the ortho-phosphate groups from the phytate molecule. Diets fed to pigs are supplemented with inorganic P, and this can increase environmental pollution and diet costs. Sixty mixed sex, half-breed pigs, were used to evaluate the effect of increasing dietary levels of phytase (253, 759, 1265 and 1748 PU kg-1 feed on animal performance as compared to a control without phytase but supplemented with dicalcium phosphate. Enzyme levels did not affect daily feed intake, food conversion, average daily weight gain, plasma P and Ca, calcium and phosphorus in bone ash, and the calcium/phosphorus ratio in the plasma and bones. A quadratic relationship between phytase levels and the percentages of P and Ca in bone ash was observed, reaching a maximum at the 880 and 879 PU levels, respectively. Animals fed diets containing phytase presented low plasma P values when compared to the control, but no effects were observed for the regression analysis. Using 759 PU phytase in rations containing corn, soybean bran and defatted rice bran for growing pigs can eliminate the use of traditional sources of P.Os animais monogástricos não aproveitam eficientemente o P orgânico das dietas, pois não sintetizam a enzima fitase, sendo necessária a suplementação das rações com P inorgânico, podendo elevar o custo das dietas e a poluição ambiental. Foram utilizados 60 leitões mestiços (machos castrados e fêmeas para avaliar a eficácia dos níveis dietéticos crescentes da enzima fitase (253, 759, 1265 e 1748 UF kg-1 de ração sobre os parâmetros de desempenho e comparar com o tratamento testemunha que diferia dos demais por não conter fitase e por conter fosfato bicálcico. Os níveis da enzima fitase não afetaram o consumo diário de ração, conversão alimentar, ganho diário de peso, P e Ca no plasma, cinzas no osso e relação cálcio e f

  7. Cinética do P nos tecidos de suínos em crescimento alimentados com dietas formuladas de acordo com o conceito de proteína ideal e suplementadas com enzima fitase

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    J.A. Moreira

    2014-10-01

    Full Text Available O presente estudo foi desenvolvido para avaliar os efeitos da enzima fitase sobre a cinética do P nos tecidos de suínos, alimentados com dietas formuladas de acordo com o conceito de proteína ideal e suplementadas com enzima fitase. Foram utilizados 20 suínos machos castrados, distribuídos em um delineamento em blocos ao acaso, com cinco tratamentos e quatro repetições. Os animais foram alojados em gaiolas metabólicas durante 17 dias, sendo 10 dias para adaptação e sete dias para coletas de fezes e urina. Amostras de sangue foram coletadas por cinco dias. No primeiro dia da fase experimental, cada animal recebeu, por via endovenosa, uma solução radioativa com 7,4MBq de 32P. No final do período experimental, os animais foram sacrificados, e amostras de tecidos do músculo (lombo, coração, fígado, rins e ossos foram coletadas. A enzima fitase interferiu na cinética do 32P, levando a uma menor incorporação nos tecidos dos ossos.

  8. DETERMINAÇÃO DOS VALORES MÉDIOS DAS ENZIMAS AST, DHL, gGT E FAS NO SORO DE EQUINOS SADIOS EM SANTA MARIA, RS

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    Sônia Terezinha dos Anjos Lopes

    1993-12-01

    Full Text Available Foram usados 50 eqüinos sadios provenientes do Batalhão de Polícia Montada da Brigada Militar em Santa Maria, RS, sendo 43 machos e 7 fêmeas com idade variadas a partir de 3 anos. Foram colhidos 10ml de sangue da jugular para determinação dos valores da atividade sérica das enzimas aspartato-aminotransferase (AST, desidrogenase lática (DHL, gama-glutamiltransferase (gGT e fosfatase alcalina sérica (FAS. Os resultados encontrados para AST foi de 101 - 190U/I com média de 130UI; DHL foi de 100 - 421 U/l com média de 182U/I; gGT foi de 2 - 27U/I com média de 6.5U/I e FAS foi de 103 - 335U/I com média de 190U/I. A partir de outubro/1992 estes valores passaram a ser referência no laboratório de Patologia Clínica do Hospital de Clinicas Veterinárias da Universidade Federal de Santa Maria.

  9. Bioprospección de enzimas de restricción en bacterias de suelos y ambientes volcánicos de Nicaragua

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    Julio A, Gómez Rodríguez

    2008-04-01

    Full Text Available LA BIOPROSPECCIÓN ES LA BÚSQUEDA SISTEMÁTICA DE USOS SOSTENIBLES y con fines comerciales de los elementos genéticos y bioquímicos de la biodiversidad. En Nicaragua realizamos bioprospección de enzimas de restricción (ER de interés biotecnológico desde el año 1999. A través de esta investigación buscamos nuevas ER en bacterias de suelos en ambientes aún inexplorados, como zonas volcánicas y agrícolas del país. Aquí reportamos la identificación de isoesquizómeros de 14 ER conocidas: BamHI, EcoRV, MboI, MaeI, HaeIII, EarI, BsoBI, BsaBI, Acl I, BsaWI, Nci I, BstNI, BssSI y HpaII, las 8 últimas termoestables. La información de las ER encontradas en Nicaragua fue registrada en REBASE (Restriction Enzyme Database. Resaltamos la importancia del estudio de la biodiversidad microbianade los ambientes volcánicos nicaragüenses, ya que favorece la investigación de la evolución de la vida, los extremos donde podemos encontrarla y sus aplicaciones a la biotecnología.

  10. ALTERACIONES EN LA PRODUCCIÓN mRNA DE ENZIMAS INTESTINALES DE CERDOS DURANTE VARIOS PERÍODOS POSDESTETE ALTERAÇÕES NA PRODUÇÃO DE mRNA DE ENZIMAS INTESTINAIS DOS SUINOS DURANTE DIVERSOS PERÍODOS APOS O DESMAME ALTERATIONS IN THE PRODUCTION mRNA OF INTESTINAL ENZYMES IN PIGS DURING SEVERAL POSTWEANING PERIODS

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    CAROLINA MONTOYA R.

    2012-12-01

    Full Text Available El objetivo de este estudio fue determinar la expresión génica de enzimas a nivel de enterocito de cerdos durante el período posdestete. El trabajo de campo se realizó con 16 cerdos destetados a los 21 días de edad en el Centro San Pablo, perteneciente a la Universidad Nacional de Colombia. Los animales fueron alimentados durante 10 días con una dieta basal que tuvo como componentes leche y algunos de sus derivados, y que además cumplía con todos los mínimos nutricionales. Los cerdos se sacrificaron escalonadamente los días 1, 5, 7 y 10 posdestete. Se realizó extracción completa del intestino delgado, el cual fue dividido en tres secciones (duodeno, yeyuno e íleon. Se evaluó la expresión génica de las enzimas digestivas por RT-PCR. El diseño estadístico empleado fue completamente al azar. Para las enzimas intestinales se presentaron disminuciones significativas, donde el día cinco posdestete presentó los menores valores(PO objetivo desta pesquisa foi determinar a expressão dos genes das aminopeptidases e dissacaridasesaonível do enterocito de suinos durante períodos apos o desmame. A experiência foi conduzida no centro de produção de San Pablo da Universidade Nacional de Colômbia (Medellín com 16 suinos desmamados aos 21 dias de vida. Os animais foram alimentados por 10 diascomuma dieta básica comleite e alguns de seus derivados, e aquele igualmente cumpriu todos os requisitos mínimos nutricionaís. Os suinos foram eutanasiados nos dias 1, 5, 7 y 10 pós-desmame. A extração completa do intestino pequeno foi realizada, que foi dividido emtrêsseções (duodeno, jejum e íleo. A expressão dos genes das enzimas digestivas por RT-PCR foi avaliada. O delineamento estatístico empregado foi completamente ao acaso. Para as enzimas intestinais as diminuições significativas foram apresentadas, onde no quinto diaapos o desmame apresentou os valores mais baixos (P0.01. O desmame precoce altera a expressão molecular das

  11. Hydrolysis of lactose by β-galactosidase from Kluyveromyces fragilis: characterization of the enzyme Hidrólise da lactose pela β-galactosidase de Kluyveromyces fragilis: caracterização da enzima

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    Graciette Matioli

    2002-03-01

    Full Text Available The β-galactosidase enzyme from Kluyveromyces fragilis was characterized in the soluble form using lactose 5% w/v found in skimmed powdered milk as substrate. Enzyme diluted 50 times hydrolyzed the lactose in batch reactor of 50 mL capacity. Enzyme activity and its activation energy were determined as a function of temperature and pH. Temperature ranged from 20 to 55ºC and pH from 5.5 to 8.0. Activation energy was 9.50 kcal/mol. The energy of deactivation was 33.74 kcal/mol. Although the enzyme presented a high specific activity at 45ºC and pH 6.5 (3.312 U/mg protein, values indicate that the best use of the enzymatic activity occur at 40ºC or below, with half-life higher than 12 hours. The activation energy increased proportionally to pH increase. Therefore, the activation energy depends on pH and varies according to the origin of the enzyme.A enzima β-galactosidase de Kluyveromyces fragilis foi caracterizada na forma solúvel, utilizando como substrato, lactose 5% p/v presente no leite em pó desengordurado. A enzima, diluída 50 vezes, hidrolisou a lactose em reator batelada de 50 ml de capacidade. A atividade da enzima e sua energia de ativação foram determinadas em função da temperatura e pH. A faixa de temperatura analisada foi de 20 a 55ºC e de pH de 5,5 a 8,0. A energia de ativação foi de 9,50 kcal/mol. A energia de desativação foi de 33,74 kcal/mol. Embora a enzima tenha apresentado uma atividade específica alta a 45ºC e pH 6,5 (3,312 U/mg proteína, os valores obtidos indicam que o melhor aproveitamento da atividade enzimática se dá a 40ºC ou abaixo, com um tempo de meia-vida superior a 12 horas. A energia de ativação aumentou proporcionalmente com o aumento de pH. Portanto, a energia de ativação depende diretamente do pH da solução e varia com a origem da enzima.

  12. Metodologia de seleção de cepas para produção etodologia da ciclodextrina glicosiltransferase e para purificação da enzima = Strains selection methodology for cyclodextrin glycosyltransferase production and enzyme purification

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    Glauciane de Lara Costa

    2007-01-01

    Full Text Available As ciclodextrinas (CDs são maltooligossacarídeos, produzidas a partir do amido, pela enzima ciclodextrina glicosiltransferase (CGTase. Esta pesquisa teve por objetivo estabelecer metodologias de seleção de cepas para produção de CGTase e para purificação da enzima. Os microrganismos foram selecionados a partir de 53 análises de solos de cultura de amido, em placas contendo meio de cultivo específico, para seleção de cepas produtoras de CGTase. As enzimas foram obtidas com cultivo destes microrganismos em meio líquido. As atividades enzimáticas das CGTases foram determinadas pelos métodos espectrofotométricos e precipitação com tricloroetileno. A cepa isolada do solo de aveia foi a que apresentou maior atividade [0,1864 mmol de b-CD (min mL-1]. Esta cepa foi utilizada para a produção da enzima em escala laboratorial e purificação em cromatografia deafinidade bioespecífica. A cepa selecionada nesta pesquisa abre novas perspectivas para produção de enzima e CDs em escala industrial.Cyclodextrins (CDs are maltooligosaccharides produced from starch by cyclodextrin glycosyltransferase (CGTase enzyme. This researchaimed at establishing method for strains selection for CGTase production and enzyme purification. The microorganisms were selected from 53 analyses of starch cultures soils on plates containing specific culture medium for strains selection that produce CGTase. Theenzymes were obtained by culturing these microorganisms in liquid medium. The enzyme activity was determined with photospectrometric methods and precipitation with trichloroethylene. The strain isolated from oat soil was the one that showed the highest activity [0.1864 mmol of b-CD (min mL-1]. This strain was used for enzyme production in laboratory scale and purification by biospecific affinity chromatography. The strain selected in this research opens new perspectives for enzymes production and CDs in industrial scale.

  13. Matriz extracelular e enzimas degradatórias na hematopoese e doenças onco-hematológicas Extracellular matrix in hematopoiesis and hematologic malignancies

    Directory of Open Access Journals (Sweden)

    Juliana L. Dreyfuss

    2008-10-01

    Full Text Available A matriz extracelular (MEC é uma rede complexa composta por quatro grandes classes de macromoléculas: colágenos, proteoglicanos (PGs, glicosaminoglicanos (GAGs e glicoproteínas adesivas. As interações entre as células e a MEC são cruciais para determinar os padrões de comportamento celular, tais como crescimento, morte, diferenciação e motilidade. A hematopoese é o sistema responsável pela produção das células sangüíneas. O controle da proliferação e diferenciação destas células é feito através da interação das células com o microambiente da medula óssea (matriz extracelular. A adesão de progenitores hematopoéticos a moléculas da MEC e a ativação das integrinas são modulados por uma variedade de citocinas e fatores de crescimento, e esta modulação parece ser o mecanismo de regulação que influencia a proliferação de células-tronco e progenitores hematopoéticos, migração transendotelial ou transestromal e homing. Tanto no processo de migração, homing e invasão tumoral, as células seguem os seguintes passos: 1 - Degradação da MEC por enzimas secretadas pelas células: metaloproteinases, colagenases, plasmina, catepsinas, glicosidases e heparanases; 2 - Locomoção das células na região da MEC previamente degradada pelas enzimas; 3 - Adesão das células via receptores específicos da superfície celular, que geralmente interagem com componentes da MEC. Nas doenças onco-hematológicas, a interação das células neoplásicas com a matriz extracelular também influencia na agressividade e prognóstico da doença.The extracellular matrix (ECM is a complex structure composed of collagens, proteoglycans, glycosaminoglycans and adhesive glycoproteins. Interactions between the cells and the ECM are crucial to determine cell behavior, such as growth, death, differentiation and motility. Hematopoiesis is the system responsible for the production of blood cells. The control of proliferation and

  14. Análisis del consumo de inhibidores de la enzima convertidora de angioténsina en el territorio oeste de La Habana, 2005-2009

    Directory of Open Access Journals (Sweden)

    José Ramón Cabrera Cepero

    2011-12-01

    Full Text Available La planificación de los recursos es un problema trascendental en los países en desarrollo y también en Cuba, por lo que hacer el mejor uso de los presupuestos limitados y de las escasas divisas, es de vital importancia. Planificar las cantidades de medicamentos necesarias, para lograr garantizar una disponibilidad adecuada de estos en todos los niveles de asistencia, es una tarea en la cual intervienen un sinnúmero de factores. El objetivo de este trabajo fue demostrar en qué medida la introducción del enalapril tabletas influyó en el consumo del captopril tabletas, mediante el análisis de los patrones de consumo de los medicamentos inhibidores de la enzima convertidora de angiotensina en el territorio oeste de La Habana entre marzo de 2005 y diciembre de 2009. Para ello se realizó un estudio de utilización de medicamentos de consumo, de tipo descriptivo, observacional y retrospectivo. Se calcularon las DHD (dosis por mil habitantes día. Los resultados de este trabajo demuestran cómo en este grupo hay un desplazamiento del consumo hacia el enalapril. Este es un comportamiento lógico por la comodidad de la administración y la menor incidencia de efectos adversos. Sin embargo, el captopril se mantiene en valores entre 20 y 30 DHD x 1 000 habitantes ya que hay un grupo de pacientes que continúan con este tratamiento y es de elección en la crisis hipertensiva.

  15. Inhibidores de la enzima de conversión de la angiotensina en el tratamiento de la hipertensión arterial

    Directory of Open Access Journals (Sweden)

    Alfredo Vázquez Vigoa

    1998-12-01

    Full Text Available Se presenta una revisión actualizada de la función de los inhibidores de la enzima de conversión de angiotensina (IECA en el tratamiento del paciente hipertenso. Se explica el mecanismo de acción de dichos fármacos, basado en el bloqueo de la generación de angiotensina II y en el incremento de péptidos vasodilatadores (bradiquinina, efectos que logran tanto a nivel del sistema renina-angiotensina circulante, como sobre el sistema renina-angiotensina hístico. Se resalta su utilidad en el paciente diabético hipertenso, donde aumenta la sensibilidad a la insulina y evita la aparición de nefropatía diabética. Se discute el impacto de los IECA sobre la regresión de la hipertrofia ventricular izquierda y su valor en la cardiopatía isquémica. Se concluye que los IECA constituyen una opción eficaz en el paciente hipertenso con normalización de las cifras de tensión arterial en el 60 % de los casos.An updated review of the function of angiotensin-converting enzyme inhibitors (ACEI in the treatment of hypertensive patient is set forth. The mechanism of the action of such drugs, based on the blocking of II angiotension generation and the increase of vasodilatador peptides (bradichinin, and their effects on both the circulating renin- -angiotensin system and the hystic renin-angiotensin system are explained. Their usefulness for treating hypertensive diabetic patient is underline since they invease sensitivity to insuline and prevent diabetic nephropathy. The impact of ACEI on regression of left ventricular hypertrophy and their importance in ischemic heart disease are discussed. It is concluded that ACEI are an effective alternative for hypertensive patient treatment because they help to normalize blood presure in 60 % of cases.

  16. ACTIVIDAD DE ENZIMAS ANTIOXIDANTES EN TEJIDOS EMBRIOGÉNICOS Y NO EMBRIOGÉNICOS DE CAÑA DE AZÚCAR

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    Marina Medeiros de Araújo Silva

    2014-05-01

    Full Text Available Este trabajo tuvo el objetivo de inducir la embriogénesis directa en segmentos de hojas jóvenes no-expandidas en la variedad de caña de azúcar RB872552 e investigar la correlación de este evento morfogénico con el estrés oxidativo. Se utilizaron dos protocolos de inducción de embriogénesis somática, previamente descritos para caña de azúcar, con distintas suplementaciones en el medio de cultivo y en las condiciones de incubación. Para la conversión de embriones en plantas se utilizó el medio MS sin fitorreguladores. Se realizaron además análisis histológicas y de actividad enzimática in tejidos embriogénicos y no embriogénicos. La formación de embriones somáticos por la vía directa ocurrió en 81% de los explantes, con la combinación de los reguladores de crecimiento 2,4-D (ácido 2,4-diclorofenoxiacético y BAP (6-bencilaminopurina e incubación bajo un fotoperiodo de 16 horas. Respecto a las enzimas antioxidantes, se observó un incremento en la actividad de peroxidase y en el contenido de proteínas solubles en los tejidos embriogénicos, mientras que la polifenoloxidase y la catalase presentaron más bajos valores de actividad en estos tejidos, en comparación con los no embriogénicos. Se podría inferir que el estrés oxidativo juega un papel importante en la inducción de la embriogénesis somática en caña de azúcar.

  17. EFFECT OF FIBROLYTIC ENZYMES ON CHEMICAL COMPOSITION OF MAIZE SILAGE EFEITO DE ENZIMAS FIBROLÍTICAS SOBRE A COMPOSIÇÃO QUÍMICA DASILAGEM DE MILHO

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    José Mauro da Silva Diogo

    2006-12-01

    Full Text Available This experiment was carried out to determine theeffect of enzymatic solution on bromatologic compositionand in situ degradability for neutral detergent fiber (NDFof maize silage. The treatments were four enzymatic levels,two fermentation periods and three replications. The levelsadopted were 0, 5, 10 and 20 mg of enzyme per kg of naturalmatter (MN of grass. Experimental silos, in triplicate, wereopened 45 and 120 days after ensiling, and DM, NDF, crudeprotein (CP, N-NH3 and pH were analyzed. In the study ofin situ degradability of DM and NDF, silage of 45 days wascollected. Nylon bag technique was used with three canulatedbovine and three incubation times (6, 24 and 96 hours. Theexperimental period was of the 36 days. The solution didn’tchange the content of DM, pH and N-NH3 values of maize silage. There was no difference on the CP amongfermentation periods of, but there was interaction betweenperiod of storage and enzymatic level. The solution increasedfinal CP of maize silage after 45 days of ensiling and thiseffect was higher to 20 mg (10.14% compared the control(8.77%. In case of NDF, maize silage treated with 10 mglevel showed lower fiber content (47.25% versus untreatedcontrol (49.96%, suggesting an improvement in the nutritivevalue. There was no difference among period of storageneither interaction period of storage and enzymatic level.In situ rumen degradation showed no difference among thetreatments on NDF degradation of maize silage. KEY WORDS: additives, cellulases, degradability, hemicellulases, cell wall. Objetivou-se avaliar o efeito de níveis de enzimasfibrolíticas sobre a composição bromatológica e adegradabilidade ruminal da fibra em detergente neutro(FDN da silagem de milho. O experimento consistiu dequatro níveis enzimáticos, dois períodos de armazenamentoe três repetições. Aplicaram-se, por aspersão, na ensilagem,os níveis enzimáticos de 0, 5, 10 e 20 mg de enzimas por kgde matéria natural (MN. Após 45 e

  18. Association of GSTs polymorphisms with risk of gestational diabetes mellitus.

    Science.gov (United States)

    Li, Yan; Li, Shaoru; Zhai, Qianqian; Hai, Jie; Wang, Di; Cao, Meng; Zhang, Qinggui

    2015-01-01

    We conducted a case-control study to investigate the association between GSTM1, GSTT1 and GSTP1 IIe105Val polymorphisms and development of gestational diabetes mellitus in a Chinese population. A total of 320 patients with gestational diabetes mellitus and 358 pregnancy subjects were consecutively collected between January 2013 and December 2014. Genotyping for detection of GSTM1, GSTT1 and GSTP1 IIe105Val was conducted by using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphisms) method. By Fisher's exact test, we found that the genotype distributions of GSTP1 IIe105Val were in line with the Hardy-Weinberg equilibrium in control subjects (P=0.57). By Chi-square test, we found significant differences in the genotype distributions of GSTM1 (χ(2)=11.49, P=0.001) and GSTT1 (χ(2)=18.50, Pgestational diabetes mellitus when compared with the present genotype, and the adjusted Ors (95% CI) were 1.71 (1.24-2.36) and 2.00 (1.44-2.79), respectively. However, the GSTP1 IIe105Val polymorphism was not associated with an elevated risk of gestational diabetes mellitus. In conclusion, we suggest that the GSTM1 null genotype and GSTT1 null genotype are correlated with an increased risk of gestational diabetes mellitus in a Chinese population.

  19. Inhibition of glutathione S-transferases (GSTs) activity from cowpea ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... 1Department of Biochemistry, Federal University of Technology, Akure, Nigeria. ... have positive results for alkaloids, saponin, tannins and flavonoids. ... binding of the extract was competitive by the Dixon plot with Ki of 84, 132 ...

  20. Inhibition of glutathione S-transferases (GSTs) activity from cowpea ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Inhibition effect of the plant extracts on the GST was studied by spectrophotometric method. The ... of assuring food security in developing countries like ..... studies on African cat fish (Clarias gariepinus) liver glutathione s-.

  1. Sucrose metabolizing enzymes in cell suspension cultures of Bauhinia forficata, Curcuma zedoaria and Phaseolus vulgaris Enzimas do metabolismo da sacarose em cultura celular de Bauhinia forficata, Curcuma zedoaria e Phaseolus vulgaris

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    Marcia Ometto de Mello

    2001-09-01

    Full Text Available The objective of this work was to study the activity of sucrose metabolizing enzymes in extracts of cell suspension cultures of Bauhinia forficata Link, Curcuma zedoaria Roscoe and Phaseolus vulgaris L. Invertase pathway was identified in the three studied species. Sucrose synthase pathway was also responsible for sucrose metabolism in Curcuma zedoaria and Phaseolus vulgaris cells. Activity values higher than 300 nmol min-1 mg-1 of protein were found for acid and neutral invertases, UDPglucose pyrophosphorylase and phosphoglucomutase in the cell extract of the three plant species. Sucrose synthase showed low activity in Bauhinia forficata cells. As sucrose concentration in the culture medium decreased, sucrose synthase activity increased in C. zedoaria and P. vulgaris cells. The glycolytic enzymes activity gradually reduced at the end of the culture period, when carbohydrate was limited.O objetivo deste trabalho foi estudar as enzimas do metabolismo da sacarose em culturas de célula em suspensão de Bauhinia forficata Link, Curcuma zedoaria Roscoe e Phaseolus vulgaris L. A via da invertase foi identificada nas três espécies estudadas. A via da sacarose sintase também foi responsável pelo metabolismo da sacarose em células de Curcuma zedoaria e Phaseolus vulgaris. Foram encontradas atividades maiores que 300 nmol min-1 mg-1 de proteína das enzimas invertase ácida e alcalina, UDPglicose pirofosforilase e fosfoglicomutase no extrato celular das três espécies de plantas. A sacarose sintase mostrou atividade baixa nas células de Bauhinia forficata. À medida que a concentração de sacarose no meio de cultura diminuiu, a atividade da sacarose sintase aumentou em células de Curcuma zedoaria e Phaseolus vulgaris. Ao final do período de cultura, quando os carboidratos se tornaram limitantes, as atividades das enzimas glicolíticas reduziram-se gradualmente.

  2. Perfil bioquímico de algumas enzimas no plasma sangüíneo de potras da raça Brasileiro de Hipismo (BH criadas em Colina, Estado de São Paulo

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    Fernando José Benesi

    2009-08-01

    Full Text Available Com o propósito de avaliar o perfil bioquímico de algumas enzimas, em potras sadias da raça BH (Brasileiro de Hipismo, utilizaram-se 380 amostras de plasma sangüíneo colhidas de 19 animais desde o nascimento até 24 meses de vida. Na análise dos resultados evidenciou-se que os valores médios das enzimas FA (fosfatase alcalina e CK (creatina quinase foram máximos entre o nascimento e 24 horas de vida (FA-1995.50 UI/ ; CK-189.13UI/L, enquanto que para a LD (lactato desidrogenase e GGT (gama glutamiltransferase as maiores magnitudes ocorreram, respectivamente, entre 3 e 4 dias (LD-479.11UI/L e aos 10 dias de idade (GGT-18.70UI/L. As FA, CK, LD e GGT, mostraram diminuições dos valores médios, respectivamente, até 6 meses (FA-323.50UI/L, 20 dias (CK-51UI/ L, 19 meses (LD-214.00UI/L e 4 meses (GGT-11.40UI/L estabilizando-se a seguir, com pequenas variações. A atividade da AST (aspartato aminotransferase que foi mínima logo após o nascimento (AST- 43.38UI/L, aumentou até os sete dias de vida (AST-110.89UI/L, e a seguir diminuiu progressivamente, com pequenas oscilações, até o final do estudo. Todas as enzimas avaliadas sofreram variações influenciadas pelo fator etário, particularmente no período inicial de vida dos animais estudados.

  3. Crescimento foliar e atividades das enzimas antioxidativas em plântulas de girassol suplementadas com percolado de aterro sanitário e submetidas a estresse hídrico

    Directory of Open Access Journals (Sweden)

    Francisco Holanda Nunes Junior

    2017-01-01

    Full Text Available Em regiões áridas ou semiáridas, a escassez hídrica tem sido um dos principais fatores limitantes da produção agrícola. Diante disso, o presente trabalho objetivou analisar os efeitos da aplicação de percolado de aterro sanitário no crescimento foliar (número de folhas e área foliar e as atividades das enzimas antioxidativas: superóxido dismutase (SOD, catalase (CAT, peroxidase do ascorbato (APX e peroxidase do guaiacol (GPX em folhas e raízes de plântulas de girassol submetidas às condições de estresse hídrico. O delineamento experimental foi o inteiramente casualizado, disposto em arranjo fatorial dois (irrigadas ou não irrigadas x quatro (areia; areia + adubo orgânico 100 kg N ha-1; areia + percolado de aterro sanitário 100 kg N ha-1; areia + percolado de aterro sanitário 150 kg N ha-1, com cinco repetições. Em relação aos parâmetros foliares, o tratamento 100 kg N ha-1 suplementado com percolado de aterro sanitário obteve os melhores incrementos no número de folhas e área foliar. Além disso, verificaram-se aumentos nas atividades das enzimas antioxidativas em folhas e raízes de plântulas de girassol suplementadas com percolado de aterro sanitário, sendo provável que as reduções dos efeitos deletérios do estresse hídrico nas variáveis foliares dos tratamentos suplementados com percolado de aterro sanitário tenham ocorrido em virtude das maiores atividades das enzimas antioxidativas, especialmente as da CAT nas folhas e GPX nas raízes.

  4. Caracterización bioquímica de la enzima bifuncional dihidrofolato reductasa-timidilato sintasa de Leishmania (Viannia y su evaluación como blanco molecular

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    Edison Osorio

    2013-09-01

    Full Text Available Introducción. La dihidrofolato reductasa (DHFR se ha utilizado como blanco molecular en tratamientos antibacterianos, anticancerígenos y antipalúdicos. También, actúa como blanco molecular en Leishmania; sin embargo, no existen reportes de la enzima bifuncional en especies de Leishmania (Viannia. Materiales y métodos. Se ha aislado y expresado en Escherichia coli el gen que codifica para la enzima bifuncional DHFR y la timidilato-sintasa (TS de Leishmania braziliensis. La enzima recombinante se purificó y caracterizó, y se evaluó el efecto inhibitorio de algunos antifolatos, así como de cuatro alcaloides aporfínicos. Resultados. El gen se compone de aproximadamente 1.560 pb y codifica un péptido de 58 kDa que contiene los dominios DHFR y TS ligados en una sola cadena polipeptídica. La enzima recombinante DHFR-TS, utilizando el dihidrofolato (H2F como sustrato, presentó valores de Km y Vmax de 55,35± 4,02 (media ± el error estándar de la media y de 0,02 ± 5,34 x 10-4, respectivamente. La enzimar DHFR-TS de L. braziliensis presentó valores de Ki para los antifolatos en el rango de micras. El metotrexato fue el inhibidor más potente de la actividad enzimática (Ki=22,0 mM en comparación del trimetoprim (Ki=33 mM y la pirimetamina (Ki=68 mM. Estos valores de Ki son significativamente más bajos en comparación con los obtenidos para los alcaloides aporfínicos. Conclusión. Los resultados muestran el efecto inhibitorio de los antifolatos sobre la actividad enzimática, lo cual indica que la rDHFR-TS de L. braziliensis podría ser un modelo para estudiar moléculas antiprotozoarias potenciales. doi: http://dx.doi.org/10.7705/biomedica.v33i3.1434

  5. Optimação de biocatalisadores: desenvolvimento de estratégias para modulação de propriedades de enzimas por técnicas físicas e químicas

    OpenAIRE

    Santos, José Cleiton Sousa dos

    2015-01-01

    Tesis doctoral inédita cotutelada por la Universidad Federal do Ceara (Benfica-Fortaleza), Centro de Tecnología, Departamento de Engenharía Química y por la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 27-02-2015 Este trabalho de tese apresenta suportes ativados com divilsulfona (DVS) como úteis para a estabilização de enzimas por ligação covalente multipontual, os suportes são muito estáveis, e reagem com diferentes grup...

  6. Efeito da aplicação de enzimas pectinolíticas no rendimento da extração de polpa de cupuaçu

    Directory of Open Access Journals (Sweden)

    BASTOS MARIA DO SOCORRO ROCHA

    2002-01-01

    Full Text Available O Brasil apresenta uma diversidade de frutas regionais, principalmente nas regiões Norte e Nordeste. Dentre estas, destaca-se o cupuaçu, que é uma fruta considerada exótica e de grande potencial comercial nos mercados dos estados do Sudeste do Brasil e dos países europeus. A polpa e a semente são importantes para o desenvolvimento de produtos industriais. A polpa tem sido estudada como matéria-prima para néctar; entretanto, é usada em sorvetes, geléias, purês e polpa enlatada. Atualmente, o processo de extração da polpa ainda é feito de maneira empírica, utilizando-se de acessórios como facas, colheres ou tesouras de uso doméstico, devido à forte aderência da mesma ao caroço, causando baixo rendimento no produto final. Com o objetivo de aumentar o rendimento durante o processo de extração da polpa de cupuaçu, adicionaram-se à polpa bruta dois tipos de preparações enzimáticas de ação pectolítica (Citrozym-L e Rohament PL. As concentrações estabelecidas foram de 100; 300; 500 e 750 ppm. Após todo o processo, obteve-se a polpa, e o rendimento foi comparado com a polpa-controle. O experimento foi realizado nos laboratórios de Tecnologia de Alimentos da Embrapa Agroindústria Tropical. Pelos resultados obtidos, observou-se que o rendimento da polpa com adição de Citrozym-L foi superior a 60% nas concentrações de 300; 500 e 750 ppm, enquanto, com a utilização de Rohament-PL, o rendimento variou de 43 a 57% nas mesmas concentrações. O rendimento da polpa-controle foi de 44 e 41 %, para os experimentos realizados com a primeira e segunda preparação enzimática, respectivamente. Conclui-se que a utilização de enzimas é uma alternativa para melhorar o processo de extração da polpa; adicionando-se acima de 300ppm, obtém-se um rendimento próximo a 60%.

  7. Meta-análise da digestibilidade ileal de aminoácidos e minerais em suínos alimentados com dietas contendo enzimas

    Directory of Open Access Journals (Sweden)

    Cheila Roberta Lehnen

    2011-04-01

    Full Text Available O objetivo deste trabalho foi avaliar, por meio da meta-análise, o efeito da fitase e da xilanase sobre a digestibilidade ileal aparente (DIa de aminoácidos, cálcio e fósforo, em suínos em fase de crescimento. A base de dados consistiu de 21 artigos publicados entre 1998 e 2009, no total de 82 tratamentos e 644 suínos. A meta-análise foi realizada por análise gráfica, de correlação, de variância-covariância. As concentrações de fósforo fítico e as frações fibra em detergente neutro, fibra em detergente ácido e lignina em detergente ácido, nas dietas, apresentaram correlações baixas e negativas com a DIa do cálcio, fósforo e aminoácidos. A adição de fitase às dietas aumentou em 2% a DIa da arginina, em 14% a do cálcio e em 34% a do fósforo. A DIa da arginina, fenilalanina, isoleucina e lisina foi 3,3% superior em suínos alimentados com dietas com xilanase, em relação às dietas sem a enzima. O fósforo fítico e as fibras, nas dietas, reduzem a DIa do cálcio, do fósforo e dos aminoácidos essenciais. O uso de fitase e xilanase, nas dietas, melhora o aproveitamento de cálcio, fósforo e alguns aminoácidos. No entanto, o excesso de cálcio e fósforo nas dietas reduz a ação da fitase sobre a digestibilidade ileal dos nutrientes.

  8. INFLUÊNCIA DE ENZIMAS DE MACERAÇÃO NA PRODUÇÃO DE PUBA INFLUENCE OF MACERATING ENZYMES IN THE PRODUCTION OF "PUBA"

    Directory of Open Access Journals (Sweden)

    Tobias José Barreto de MENEZES

    1998-10-01

    Full Text Available Pubagem é a fermentação natural de raízes de mandioca para produção da puba, um alimento popular do Nordeste do Brasil. Além da fermentação lática predominante, os microrganismos também causam o amolecimento das raízes, importante para a obtenção de um produto de boa qualidade. O objetivo deste trabalho foi detectar a presença de enzimas de maceração e verificar a influência da adição de preparados comerciais de celulase e pectinase na pubagem. Constatou-se que as atividades de celulases, xilanase e poligalacturonase aumentaram durante a fermentação natural. Ao se adicionar preparados comerciais de celulase e pectinase este aumento foi maior do que o esperado pela fermentação natural. A adição desses preparados enzímicos acelerou a fermentação aumentando a acidez e reduzindo o pH mais rapidamente do que o tratamento-testemunha.Retting is the natural fermentation of cassava for the production of puba, a common food of the Northeast of Brazil. In addition to a predominant lactic acid fermentation, the microoganisms also cause the softening of the roots which is important for obtaining a good quality product. The objective of this work was to detect the presence of macerating enzymes and to verify the influence of the addition of a commercial preparation of cellulase and pectinase on the retting of cassava. It was found that the activities of cellulases, xilanase and poligalacturonase increased during natural fermentation. This increase was higher than that expected by natural fermentation when commercial preparations of cellulase and pectinase were added. The additions of these enzymic preparations speeded up the fermentation process increasing the acidity and reducing the pH more rapidly than in the control samples.

  9. Dietas à base de milho e farelo de soja suplementadas com enzimas na alimentação de frangos de corte Corn and soybean meal based diets supplemented with enzymes in feed of broiler chicken

    Directory of Open Access Journals (Sweden)

    Delma Maria Torres

    2003-02-01

    Full Text Available Com o objetivo de verificar o efeito da adição de enzimas digestivas exógenas em dietas à base de milho e farelo de soja sobre o desempenho de frangos de corte, conduziu-se este experimento. Foram utilizados 819 pintos Hubbard em DIC e esquema fatorial 3 x 2 x 2 + 1 (enzimas, proteínas, níveis de energia e um tratamento testemunha com 3 repetições de 21 aves por parcela. Os níveis de enzimas foram 0,5; 1,0 e 1,5 g/kg de dieta, e os de proteína foram normais (21,18, 19,95 e 19,43% PB e reduzidos (20,54, 19,35 e 18,46% PB; os de energia também foram normais (3000, 3100 e 3200 kcal/kg de EM e reduzidos (2910, 3007 e 3040 kcal/kg de EM, respectivamente, para as fases inicial, de crescimento e final da criação, e para o testemunha, a ração continha níveis normais de EM e PB, sem enzimas. Os fatores avaliados foram ganho de peso, consumo de ração, conversão alimentar e fator europeu de produção. Pelos resultados, verificou-se manutenção do desempenho zootécnico das aves em razão da aplicação de enzimas, constatado pela não significância desses fatores aos 42 dias de idade e pela melhora na conversão alimentar, redução do consumo de ração e maior fator europeu de produção aos 21 dias de idade. O estudo da interação dos níveis de enzima x proteína mostrou que a adição de 0,5 g/kg de enzima na dieta com nível de proteína reduzido resultou em maior ganho de peso das aves. Conclui-se que é viável o uso de enzimas exógenas adicionadas em rações para frangos de corte.The objective of the experiment was verify the effect of the addition of exogen digestive enzymes in corn and soybean meal based diets on performance of broiler chickens. Were used 819 Hubbard chickens in completely randomized design, and 3 x 2 x 2 + 1 check factorial (enzyme, protein and energy levels and one treatment check with 3 replications, of the 21 birds by replicate. Enzyme levels were 0.5, 1.0 and 1.5 g/kg of diet, energy levels were

  10. Efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes em frangos de corte de 1 a 21 dias de idade Effect of pelleting and addition of enzymes and vitamins on the performance and advantage of energy and nutrients in broiler chickens from 1 to 21 days old

    OpenAIRE

    José Laureano Barbosa Leite; Paulo Borges Rodrigues; Elias Tadeu Fialho; Rilke Tadeu Fonseca de Freitas; Adriano Kaneo Nagata; Vinícius de Souza Cantarelli

    2008-01-01

    Conduziu-se este experimento para avaliar o efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes, em frangos de corte de 1 a 21 dias de idade. Foram utilizados 350 pintos de corte, COBB, machos, com peso inicial médio de 47g ± 2,5g, em um delineamento inteiramente casualizado, com os tratamentos em arranjos fatorial 3 x 2 (três dietas, com e sem enzimas) sendo que as dietas consistiram de uma ração farelada e duas rações peletizadas...

  11. 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

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    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.

  12. Polimorfismo inserción/deleción del gen de la enzima convertidora de angiontensina y enfermedad coronaria en la población de Montería, Córdoba

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    Manolo I Jaramillo

    2013-09-01

    Full Text Available Antecedentes y objetivo: el polimorfismo inserción/deleción del gen de la enzima convertidora de angiotensina, ha sido identificado como un potente factor de riesgo de enfermedad coronaria. Para la población de Montería se desconocen las frecuencias con las que se expresan los alelos de este gen y el carácter de su interacción con condiciones de riesgo cardiovascular. El objetivo de este trabajo fue determinar, para dicha población, la asociación de este polimorfismo y el riesgo de sufrir enfermedad coronaria. Método: se llevó a cabo un estudio retrospectivo con 70 casos y 70 controles; como casos se consideraron pacientes con padecimientos coronarios confirmados por electrocardiograma, remitidos a la Organización Cardiodiagnóstico de Córdoba, y como controles individuos voluntarios sin antecedentes cardiovasculares y sin relación filial. El ADN requerido se extrajo a partir de sangre periférica. La caracterización del polimorfismo se hizo mediante reacción en cadena de la polimerasa. Resultados: la distribución de genotipos de la enzima convertidora de angiotensina en pacientes casos no fue significativamente diferente a la estimada en pacientes controles (X2=3.687, p=0,1583. El genotipo más frecuente en la población fue ID (40,72%. En el grupo casos, el genotipo II fue más frecuente que el genotipo DD comparado con el grupo control (p<0,05. El modelo de regresión logística múltiple ajustado, indicó no significancia del genotipo DD como factor de riesgo coronario (razón de disparidad = 0,51 IC95% = 0,25 – 1,06. Conclusión: el polimorfismo I/D del gen de la enzima convertidora de angiotensina no mostró ser un factor de riesgo significativo para enfermedad coronaria en la población de Montería.

  13. RELACION DE LA EXPRESION DEL RECEPTOR DE INSULINA CON LA EXPRESION DE LAS ENZIMAS GLICOGENICAS (GS1 Y GS2) Y GLUCONEOGENICAS EN LAS CELULAS DE TUBULO PROXIMAL DE RATAS NORMALES Y DIABETICAS

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    GATICA GUTIERREZ, RODRIGO ORLANDO; GATICA GUTIERREZ, RODRIGO ORLANDO

    2012-01-01

    En el presente estudio se determinó los efectos sobre la expresión y localización del receptor de insulina (InsR), de glicógeno sin tasa (GS) y de las enzimas glicolíticas y gluconeogénicas en diabetes de largo plazo. Insulina es esencial para el manejo energético del cuerpo, sin embargo, su rol a nivel renal es poco conocido. Su unión al receptor de insulina provoca una cascada de señalización intracelular, que regula múltiples procesos biológicos, tales corno el metabolismo lipídico y pr...

  14. Palmito de pupunha (Bactris gasipaes Kunth. composição mineral e cinética de enzimas oxidativas Heart of palm (Bactris gasipaes Kunth.: mineral composition and kinetics of oxidative enzymes

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    Nathália Ottoboni Galdino

    2008-09-01

    Full Text Available A análise da presença de enzimas oxidativas como a peroxidase (POD e a polifenoloxidase (PPO e o controle da atividade destas enzimas são importantes na preservação e no processamento de alimentos. Este trabalho teve por objetivo determinar a atividade enzimática da polifenoloxidase (PPO e da peroxidase (POD do palmito de pupunha, bem como avaliar o comportamento destas enzimas frente ao tratamento térmico e assim calcular a cinética de inativação térmica das mesmas para suas porções termorresistente e termolábil. Para a extração de peroxidase (POD e polifenoloxidase (PPO de palmito, utilizou-se solução tampão fosfato de sódio 100 mM com diferentes pHs (5,5; 6,0; 6,5 e 7,0. O melhor pH de extração da POD foi 5,5 e da PPO, 6,5. Estes extratos foram tratados em diferentes temperaturas (65, 70, 75 e 80 °C por períodos de 1 a 10 minutos. A POD e a PPO sofreram um decréscimo de 70 e 80%, respectivamente, em relação às suas atividades iniciais. As energias de ativação, nas temperaturas estudadas, para a porção termolábil e termorresistente da peroxidase foram 154,0 e 153,0 kJ.mol-1, respectivamente, enquanto que para a polifenoloxidase foram 26,3 e 27,0 kJ.mol-1, respectivamente. Resultados apresentaram valores que estão dentro da faixa de energia de ativação reportada para o processo de inativação térmica de enzimas.Analysis of oxidative enzymes such as peroxidase (POD and polyphenoloxidase (PPO and the control of the activity of these enzymes are important in food preservation and also in food processing. The aim of this work was to determine polyphenoloxidase (PPO and peroxidase (POD enzymatic activity in heart of palm, as well as to evaluate enzyme behavior during thermal treatment, determining the kinetics of thermal inactivation of the heat resistant and heat labile portions. For the extraction of peroxidase (POD and polyphenoloxidase (PPO from the heart of palm solution, 100 mM sodium phosphate buffer with

  15. Atividade β-D-N-Acetilglucosaminidásica de enzimas imobilizadas extraídas da Artemia franciscana e possíveis aplicações biotecnológicas

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    Santos, Pablo de Castro

    2008-01-01

    A β-D-N-acetilglucosaminidase, extraída e parcialmente isolada do crustáceo Artemia franciscana através de precipitação com sulfato de amônio e cromatografia em gel filtração Bio Gel A 1.5m foi imobilizada em Dacron ferromagnético rendendo um derivado insolúvel ativo contendo 5,0 unid/mg de proteína e retendo 10,35% da atividade da enzima solúvel. A β-D-N-acetilglucosaminidase-Dacron ferromagnético foi facilmente removida do meio reacional com o auxílio de um campo magnético e pô...

  16. “extracción, purificación parcial y secado de la enzima bromelina obtenida a partir del corazón de la piña (ananas comosus)”.

    OpenAIRE

    Quinde Fuentes, Carmina Stefania; Sánchez Lluguín, Nancy Viviana

    2013-01-01

    El presente artículo tuvo como objetivo la purificación parcial de la enzima bromelina mediante el sistema bifásico acuoso (SBA), evaluando el efecto del pH y las concentraciones de los componentes PEG 8000 y sales fosfato del sistema. La bromelina fue extraída del corazón de la piña de la variedad Milagreña mediante solución buffer a 4°c con EDTA, cisteína y fosfato disódico anhídrido. El mejor resultado de purificación obtenido en el sistema bifásico acuoso fue el que consistió de 16% PEG, ...

  17. Influencia de la alimentación sobre el ritmo circadiano de las enzimas digestivas en el cultivo de juveniles de la langosta de agua dulce Cherax quadricarinatus (Parastacidae

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    Hernán J Sacristán

    2013-09-01

    Full Text Available Se analiza en juveniles en etapa de engorde (7 g de Cherax quadricarinatus, el ritmo circadiano de los niveles de proteínas totales, la actividad de las proteasas, lipasas y amilasas, y su posible modificación en función del momento de alimentación matutino (8 h y vespertino (17 h. En general, la actividad de las enzimas digestivas de los juveniles de C. quadricarinatus no mostró un patrón circadiano de secreción, a excepción de las lipasas, donde se observó un incremento de actividad hacia la tarde-noche y disminución hacia las primeras horas de la mañana. Los niveles de proteína total, la actividad de proteinasas y amilasas registradas en la glándula digestiva, permanecieron prácticamente inalterados en todos los experimentos. A pesar de ello, se observó tendencia a que los niveles de actividad de proteinasas disminuyan luego del pulso de alimentación, recuperando los niveles anteriores 3 h después, independientemente del horario de alimentación. En cambio la actividad de amilasa no mostró ninguna tendencia por efecto del horario de alimentación. El estudio de los patrones de secreción de las enzimas digestivas y sus posibles modificaciones, podría ser utilizado como una herramienta para establecer los momentos del día más propicios para la alimentación de los juveniles en cultivo.

  18. Production of hydrolytic enzymes by the plant pathogenic fungus Myrothecium verrucaria in submerged cultures Produção de enzimas hidrolíticas pelo fungo fitopatogênico Myrothecium verrucaria em culturas submersas

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    Fabiana Guillen Moreira

    2005-03-01

    Full Text Available The capability of the plant pathogenic fungus Myrothecium verrucaria to produce extracellular hydrolytic enzymes in submerged cultures was studied using several substrates. The fungus was able to produce different depolymerases and glycosidases, being xylanase, pectinase and protease the most important. Lipase was found in cultures developed in the presence of olive oil, while protease activity was detected in all cultures. Xylanase and pectinase were optimally active at pH 4.5-5.5, while protease was active in a large range of pH 3.5 to 11.0. All three enzymes were maximally active at 40ºC and they were stable for several hours at temperature up to 50ºC.A capacidade do fungo fitopatogênico Myrothecium verrucaria produzir enzimas hidrolíticas extracelulares em culturas submersas foi estudada utilizando diversos substratos. O fungo foi capaz de produzir diferentes depolimerases e glicosidases, sendo xilanases, pectinases e proteases as mais importantes. Atividade lipase foi encontrada nos filtrados das culturas desenvolvidas na presença de óleo de oliva, enquanto atividade proteolítica foi detectada em todas as culturas. Xilanase e pectinase foram otimamente ativas em pH 4,5 a 5,5, enquanto protease foi ativa em ampla faixa de pH (3,5 a 11,0. As três enzimas foram otimamente ativas 40ºC e estáveis por várias horas a temperaturas até 50ºC.

  19. Efeito do uso de enzimas sobre o desempenho e metabolismo de poedeiras Effect of the use of enzymes on the performance and metabolism of laying hens

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    Maurício Tárcio dos Santos Viana

    2009-06-01

    Full Text Available Objetivou-se verificar o efeito da adição do complexo enzimático (CE sobre o desempenho e o metabolismo de poedeiras. Foram utilizadas 216 poedeiras da linhagem Bovans Goldline, distribuídas em delineamento experimental inteiramente casualizado, com 12 repetições de seis aves por unidade experimental e 3 tratamentos: controle positivo; controle negativo; e controle negativo + Rovábio® Max (100 g/t. A dieta controle positivo foi formulada segundo recomendações das tabelas brasileiras e a dieta controle negativo foi calculada reduzindo os nutrientes presentes na matriz nutricional da enzima de acordo com a empresa produtora. Avaliaram-se o consumo de ração, a produção de ovos, o peso dos ovos, a massa de ovo, a conversão por massa de ovo, a conversão alimentar por dúzia (CAD e os componentes do ovo no período de 24 a 36 semanas de idade. No ensaio de metabolismo, calcularam-se os valores do coeficiente de digestibilidade da matéria seca, da energia metabolizável aparente (EMA e da energia metabolizável corrigida (EMAn, bem como seus coeficientes de metabolizabilidade e a retenção de nitrogênio e do balanço de P e Ca das dietas. Nas aves mantidas com a dieta controle negativo, a adição de complexo enzimático na dieta melhorou o percentual de postura e a conversão alimentar por dúzia. A redução dos níveis nutricionais das dietas resultou em menores valores de EMA e EMAn. A suplementação de complexo enzimático às dietas com menores níveis nutricionais melhorou os valores de EMA, resultando em valores similares aos obtidos nas aves alimentadas com a ração controle positivo. Poedeiras alimentadas com a ração controle positivo apresentam maior ingestão, excreção e retenção de fósforo (mg/ave/dia, entretanto, quando a ração é suplementada com complexo enzimático, ocorre maior retenção de fósforo pelas aves.The effect of the addition of multienzymatic complex on performance and metabolism of laying

  20. Influencia de especies forestales sobre la actividad de las enzimas fosfatasa ácida y proteasas en un suelo de bosque Influence of tree species on the activity of acid phosphatase and protease in a forest soil

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    Rl Defrieri

    2008-12-01

    Full Text Available Los distintos tipos de cubiertas vegetales y especialmente las especies arbóreas dominantes en los sistemas forestales, afectan las propiedades químicas y bioquímicas de los suelos. Dado que la concentración de algunos nutrientes en la hojarasca, entre ellos N y P, es considerada crítica para la descomposición del material vegetal, el objetivo de este trabajo ha sido estudiar a dos profundidades, la influencia del aporte de biomasa vegetal proveniente de especies forestales dominantes, sobre la actividad de las enzimas fosfatasa ácida y proteasas en un suelo de un monte del Parque Chaqueño Argentino. Se extrajeron muestras de suelo, ubicadas debajo de árboles de cuatro especies del monte, a dos profundidades (0-10 y 10-20 cm, en verano y en invierno sobre las que se determinaron las actividades enzimáticas mencionadas y algunas propiedades edáficas. Para todas las especies y en las dos épocas de muestreo se comprobó que los valores de las actividades de las dos enzimas y los parámetros edáficos analizados resultaron significativamente menores en las muestras a la profundidad de 10-20 cm. La influencia de las especies forestales sobre la actividad de las enzimas estudiadas se puso de manifiesto en el muestreo superficial en donde es mayor la influencia de la incorporación de los residuos orgánicos y en verano. En estas condiciones los valores de las actividades enzimáticas medidas debajo de cada especie oscilaron entre 1.600 y 900 μg p-nitrofenol g-1 h-1 para fosfatasa ácida y entre 850 y 450 mg tirosina g-1h-1 para proteasa. Para dos de las especies estudiadas se pudo vincular la magnitud de su aporte vegetal, su tasa de descomposición y los valores de N y P en hojas senescentes con la magnitud de la liberación de ambas enzimas al suelo según la especie. No se encontró asociación de la influencia de las especies con algunos parámetros edáficos analizados. Por lo tanto la actividad de las enzimas medidas en este trabajo

  1. Influence of carbon source, pH, and temperature on the polygalacturonase activity of Kluyveromyces marxianus CCMB 322 Influência da fonte de carbono, pH e temperatura na atividade da enzima poligalacturonase de Kluyveromyces marxianus CCMB 322

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    Rodrigo de Queiroz Oliveira

    2012-09-01

    Full Text Available Microbial pectinolytic enzymes are known to play a commercially important role in a number of industrial processes. Two kinds of yeast can be discerned regarding the production of enzymes. One group includes those which can produce enzymes in the absence of an inducer, and the other group comprises the yeasts that produce enzymes in the presence of an inducer. The objective of this study was to investigate the influence of pectic substances, glucose, pH, and temperature on the polygalacturonase activity by Kluyveromyces marxianus CCMB 322. The yeast was grown in a fermentation broth containing different concentrations of glucose and pectic substances. The polygalacturonase activity was determined by the DNS method, and the pH and temperature were optimized using a central composite experimental design. The polygalacturonase secreted by K. marxianus CCMB 322 was partially constitutive showing optimum pH and temperature of 7.36 and 70 °C, respectively, and maintained approximately 93% of its original activity for 50 minutes at 50 °C. Thermal stability of the polygalacturonase enzyme was studied at different temperatures (50, 60, 70, and 80 °C and different incubation times (0, 10, 20, 30, 40, and 50 minutes. This study showed that glucose can influence the regulation of the synthesis of polygalacturonase.Enzimas pectinolíticas de origem microbiana são conhecidas por desempenhar um papel importante comercialmente em uma série de processos industriais. Dois tipos de levedura podem ser distinguidos para a produção dessas enzimas. Um grupo inclui aqueles que têm capacidade de produzi-las na ausência de um indutor e outro grupo compreende as leveduras que as produzem na presença de um indutor. O objetivo deste estudo foi investigar a influência de substâncias pécticas, de glicose, do pH e da temperatura na atividade da poligalacturonase de Kluyveromyces marxianus CCMB 322. O cultivo foi em caldo de fermentação contendo diferentes

  2. Screening of filamentous fungi for production of enzymes of biotechnological interest Seleção de fungos filamentosos para a produção de enzimas de interesse biotecnológico

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    Luis Henrique S. Guimarães

    2006-12-01

    Full Text Available Many enzymes produced by fungi have relevant biotechnological applications in several industrial areas. The purpose of this study was to collect and isolate filamentous fungi from soil and humus, plants and sugar cane bagasse of different regions of the São Paulo state. Forty isolates were examined for their ability to produce xylanase, glucose-oxidase, alkaline phosphatase, acid phosphatase, phytase, pectinase and amylase. Among these, twenty three isolates exhibited enzymatic potential. The xylanases produced by two of these isolates (Aspergillus caespitosus and A. phoenicis showed good potential for pulp bleaching. Among seventeen isolates, at least three produced high levels of glucose-oxidase, being Rhizopus stolonifer and A. versicolor the best producer strains. A. caespitosus, Mucor rouxii, and nine others still not identified were the best producers of phosphatases in submerged fermentation. Pectinase was best produced by IF II and C-8 belong R. stolonifer. Significant levels of amylase were produced by Paecilomyces variotii and A. phoenicis. A remarkable enzyme producer was Rhizopus microsporus var. rhizopodiformis that produced high levels of amylase, alkaline and acid phosphatases, and pectinase. Some morphological structures of this fungus were illustrated using light microscopy (LM and scanning electron microscopy (SEM. This study contributes to catalogue soil fungi isolated in the state of São Paulo, and provides additional information to support future research about the industrial potential of these microorganisms that may produce enzymes and, eventually, also secondary metabolites with anti-microbial or anti-parasitic activities.Muitas enzimas produzidas por fungos têm relevantes aplicações em diferentes áreas industriais. O objetivo desse trabalho foi coletar e isolar fungos filamentosos do solo e humus, plantas e bagaço de cana de açúcar de diferentes regiões do Estado de São Paulo. Quarenta isolados foram

  3. Alterations in muscular enzymes of horses competing long-distance endurance rides under tropical climate Alterações em enzimas musculares de cavalos em competições de enduro de longa distância em clima tropical

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    A.R. Teixeira-Neto

    2008-06-01

    Full Text Available This study tried to monitor the alterations of muscle enzymes activity - creatinokinase (CK, lactate dehydrogenase (LDH, and aspartate aminotransferase (AST - in a group of horses that participated of 70 and 100km distance rides in five competitions of an annual endurance championship under tropical climate. Pre ride levels (U/l were 245.13±9.84 for CK, 496.61±14.76 for LDH, and 328.95±8.65 for AST. When compared to these levels, the results revealed a significant decrease in all enzymes activities in the first moment of the rides. Peak levels, significantly different, were reached, immediately after rides by CK (413.591±50.75; 24 hours post rides by LDH (628.61±33.30; and 48 hours after rides by AST (389.89±16.96. Monitoring of recovery period revealed different behavior among enzymes activities with CK values returning to pre ride values (279.61±23.05 24 hours post rides, while LDH and AST values returned to pre ride values (505.25±33.78 and 359.35±24.90, respectively 72 hours post rides. These data revealed different alterations in concentration of muscular enzymes in endurance horses directly related to the duration of the effort.Estudaram-se as alterações de atividade das enzimas musculares creatino quinase (CK, lactato desidrogenase (LDH e aspartato aminotransferase (AST em um grupo de cavalos que utilizados em provas de enduro de 70 e 100km de distância, em cinco competições. Os valores (U/l basais (antes da largada foram 245,13±9,84 para CK, 496,61±14,76 para LDH e 328,95±8,65 para AST. Todas as atividades das enzimas decresceram no primeiro momento das provas (~30km. Valores de pico, significativamente diferentes, foram alcançados para CK (413,59±50,75 imediatamente após 70km de distância; 24 horas após para LDH (628,61±33,30; e 48 horas após as provas para AST (389,89±16,96. A monitoração do período de recuperação revelou diferente comportamento entre as concentrações enzimáticas com CK retornando aos

  4. MANNAN OLIGOSACCHARIDES AND ENZYMES IN CORN AND SOYBEAN MEAL BASED-DIETS FOR BROILERS MANANOLIGOSSACARÍDEOS E ENZIMAS EM DIETAS À BASE DE MILHO E FARELO DE SOJA PARA AVES

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    Vera Maria Barbosa de Moraes

    2007-09-01

    Full Text Available

    Mannan oligosaccharides, as an alternative to an-tibiotics, show promising results related to bird perfor-mance, immunity stimulus and improvement of intestinal mucosa. Enzyme inclusion in diets containing mannan oli-gosaccharides could improve these results. Poultry diets consist of corn and soybean meal, and approximately 30% of the phosphorus (P in these ingredients is bound to phytic acid. Phytase is capable of release not only the P but also other nutrients that can be better used by the birds while corn is relatively free of viscosous nonstarch poly-saccharides (NSP, soybean has about 20% of NSP, whose digestibility is almost null. NSP`s insoluble component of corn and soybean encapsulate nutrients and are responsive to exogenous enzymes. Negative environmental and nutri-tional consequences of dietary phytic acid are reduced by phytase inclusion in monogastric diets. Additionally, the enzymatic complex supplementation improves the nutri-tional value of feedstuffs through higher digestibility in birds. Finally, the use of exogenous enzymes allows re-duction in feed costs.

    KEY-WORDS: Animal nutrition, enzymatic supplementation, prebiotic.

    Os mananoligossacarídeos, como alternativa aos antibióticos, têm apresentado resultados promissores no que se refere tanto ao desempenho das aves quanto ao estímulo da imunidade e à melhora da mucosa intestinal. A inclusão de enzimas nas dietas contendo mananoligossacarídeos poderia melhorar ainda mais esses resultados. As dietas para aves são compostas de milho e farelo de soja, principalmente, e cerca de 30% do fósforo (P desses in-gredientes estão ligados ao ácido fítico. A fitase libera não só o P, mas também outros nutrientes para que sejam me-lhor utilizados pelas aves. O milho é relativamente isento de polissacarídeos não-amiláceos (PNAs viscosos e a soja apresenta cerca de 20% de PNAs, com digestibilidade praticamente nula. Os componentes insolúveis dos PNAs do

  5. Desempenho de Frangos de Corte Alimentados com Dietas à Base de Milho e Farelo de Soja, com ou sem Adição de Enzimas Performance of Broilers Fed Corn Soybean Meal Based Diets, with or without Inclusion of Enzymes

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    Geferson Fischer

    2002-01-01

    Full Text Available O experimento foi conduzido com o objetivo de avaliar o efeito da inclusão de um composto multi-enzimático à base de proteases, amilases e celulases (Vegpro, adicionado na proporção de 1 kg para cada 200 kg de farelo de soja, na dieta de frangos de corte. Foram utilizados 2240 pintos, fêmeas, da marca comercial Ross, submetidos a oito tratamentos, com sete repetições. O delineamento experimental utilizado foi em blocos ao acaso, com parcelas divididas. Os tratamentos foram os seguintes: T1 (controle positivo -- ração normal, sem enzima, T2 (controle negativo -- ração com níveis energético, protéico e aminoacídico do farelo de soja, superestimados em 5%, sem enzima, T3 (ração normal, sem enzima até 28 dias, com enzima de 29 a 35 dias, T4 (ração normal, sem enzima até 21 dias, com enzima de 22 a 35 dias, T5 (ração normal, com enzima, T6 (até os 28 dias, ração normal com enzima, e ração superestimada com enzima, dos 29 aos 35 dias, T7 (ração normal, com enzima até os 21 dias e ração superestimada, com enzima, do 22º ao 35º dia e T8 (ração superestimada com enzima. Na primeira fase experimental, à exceção do T2, não houve diferença significativa entre os tratamentos para peso corporal médio, ganho médio de peso e consumo de ração, pois não foi observado efeito da inclusão de enzima. A conversão alimentar diferiu estatisticamente a 5%. Na quarta semana experimental, novamente o T2 foi o único a diferir a 5% para peso corporal médio e ganho médio de peso. Para consumo de ração e conversão alimentar, os tratamentos não diferiram significativamente. Na última semana, foram notadas as maiores diferenças entre os tratamentos. Verificou-se que a inclusão do complexo multi-enzimático não proporcionou ganhos ao desempenho de frangos de corte.This study was run to evaluate the effect of inclusion of an enzymatic cocktail, containing proteases, amilases and cellulases (Vegpro in broiler diets. The

  6. Efeito de enzimas de maceração na textura do palmito (Euterpe edulis Mart Influence of cellulase, pectinase and hemicellulase on the texture of hearts of palm (Euterpe edulis Mart.

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    Regina Kitagawa GRIZOTTO

    1997-12-01

    Full Text Available Com a finalidade de ampliar o aproveitamento da palmeira produtora do palmito estudou-se a influência da poligalacturonase e de enzimas maceradoras na textura das partes semi-rígidas do vegetal não-comestíveis, incubando-se preparados comerciais de celulase, hemicelulase e poligalacturonase com o palmito preparado na forma de pequenos toletes (1-3 cm de comprimento e em porções de 2cm do raquis do vegetal. Embora os tratamentos com hemicelulase e mistura de hemicelulase e poligalacturonase tenham promovido ligeiro amaciamento do palmito, os resultados mostraram ,de modo geral, acréscimo na textura do palmito cortado em porções de 3,0 cm e em fatias de 1,0 cm indicando solubilização intensa das regiões suscetíveis a hidrólise com a permanência das regiões duras mais ricas em lignina. Como nos outros tecidos do palmito, no raquis fibroso, não foi comprovada estatiscamente a ação das enzimas na textura do vegetal.With the aim of amplifying the utilization of the palm tree the influence of poligalacturonase and macerating enzymes on the texture of the hard tips of hearts of palm was studied, incubating commercial preparations of cellulase , hemicellulase and poligalacturonase with the hearts of palm, prepared as small stalks of 1-3 cm length and with 2 cm portions of the rachis of the plant. Although the treatments containing hemicellulase and a mixture of hemicellulase and poligalacturonase promoted a slight softening of the hearts of palm, the results generally showed a hardening of the texture of the hearts of palm prepared as stalks of 1 to 3 cm indicating great solubilization of the parts susceptible to hydrolysis, the hard lignin rich parts remaining intact. As in the other tissue of the plant, in the rachis of the fibrous hearts of palm, the action of the enzymes was not statiscally proven.

  7. Producción y purificación parcial de enzimas hidrolíticas de Aspergillus ficuum en fermentación sólida sobre residuos agroindustriales

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    Marcia Costa

    2010-07-01

    Full Text Available Título en inglés: Production and partial purification of Aspergillus ficuum hydrolytic enzymes in solid state fermentation of agroindustrial residues Resumen En el presente trabajo se describe la producción de las enzimas fitasa, celulasa, xilanasa y proteasa con Aspergillus ficuum cepa DSM 932 mediante fermentación en estado sólido (SSF usando torta de canola y pomaza de cranberry como sustratos. Como medida indirecta de la producción de las enzimas se usó en cada caso la actividad enzimática. la torta de canola resultó ser un mejor sustrato para fitasa, celulasa y xilanasa, en tanto que la pomaza de cranberry resultó ser un sustrato potencial para proteasa. Mediante ultrafiltración escalonada fue posible purificar parcialmente los extractos enzimáticos de fitasa, celulasas y xilanasas, obtenidos a partir de torta de canola. La fitasa resultó tener un tamaño >100 kDa, en tanto que las celulasas y xilanasas presentan actividad en los retenidos de 10, 30 y 50 kDa, lo que indicaría que las isoenzimas de ambos complejos tienen pesos moleculares que oscilan entre 10 y 100 kDa. Palabras clave: fermentación sólida; torta de canola; Aspergillus ficuum; fitasa; xilanasa. Abstract In this paper, describes the production of the enzymes phytase, cellulase, xylanase and protease by Aspergillus ficuum DSM 932 strain, in solid state fermentation (SSF using canola cake and cranberry pomace as substrates. The enzyme activity was used in each case as an indirect measure of the enzymes production. Canola meal turned out to be a better substrate for phytase, cellulase and xylanase, while cranberry pomace was found to be a potential substrate for protease. Various ultrafiltration operations were carried out, decreasing the cut off membranes out in order to purify partially extracts of enzymes phytase, cellulase and xylanase, obtained from canola meal. Phytase was found to have a size >100 kDa, whereas cellulase and xylanase activity present in the

  8. Disponibilidade de fósforo estimada por três métodos químicos e pela atividade de duas enzimas em solos que receberam incorporação de materiais orgânicos

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    R. S. Berton

    1997-12-01

    Full Text Available A disponibilidade de fósforo em amostras dos solos Aquatibia (solo aluvial e Hoda (podzólico vermelho-amarelo eutrófico, incubados com quantidades crescentes de materiais orgânicos (palha de cevada, parte aérea de feijão-caupi, esterco de curral e lodo de esgoto, foi estimada por três métodos químicos e pela atividade das enzimas fosfatase ácida e fosfodiesterase, no Departamento de Ciências do Solo e Ambientais da Universidade da Califórnia/Riverside, de janeiro a novembro de 1985. Em estudo em casa de vegetação, a produção de matéria seca e a quantidade de P absorvida pela parte aérea de plantas de milho cultivadas nos solos que receberam os mesmos materiais orgânicos foram determinadas. A disponibilidade de P medida pela extração com água correlacionou-se, significativamente, apenas quando o esterco de curral e o lodo de esgoto foram adicionados aos solos Aquatibia e Hoda, respectivamente. A resina de troca aniônica e o Mehlich 1 foram os métodos mais indicados para determinar a disponibilidade de P para o milho quando os solos receberam quantidades crescentes dos materiais orgânicos. As altas quantidades de P extraídas pela resina de troca aniônica do solo com alta capacidade de adsorção de P indicaram que esse método foi o que melhor considerou os fatores intensidade e capacidade do solo. A atividade da enzima fosfodiesterase do solo revelou ser um bom índice para a determinação do P disponível para o milho, quando os solos receberam a adição do feijão-caupi e do esterco de curral.

  9. Resistance to ACCase inhibitors in Eleusine indica from Brazil involves a target site mutation Resistência aos inibidores de ACCase em Eleusine indica do Brasil envolve uma mutação na enzima alvo

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    M.D. Osuna

    2012-09-01

    Full Text Available Eleusine indica (goosegrass is a diploid grass weed which has developed resistance to ACCase inhibitors during the last ten years due to the intensive and frequent use of sethoxydim to control grass weeds in soybean crops in Brazil. Plant dose-response assays confirmed the resistant behaviour of one biotype obtaining high resistance factor values: 143 (fenoxaprop, 126 (haloxyfop, 84 (sethoxydim to 58 (fluazifop. ACCase in vitro assays indicated a target site resistance as the main cause of reduced susceptibility to ACCase inhibitors. PCR-generated fragments of the ACCase CT domain of the resistant and sensitive reference biotype were sequenced and compared. A point mutation was detected within the triplet of aspartate at the amino acid position 2078 (referred to EMBL accession no. AJ310767 and resulted in the triplet of glycine. These results constitute the first report on a target site mutation for a Brazilian herbicide resistant grass weed.Eleusine indica (ELEIN é uma espécie monocotiledônea, diploide. No Brasil, ela desenvolveu resistência aos inibidores da ACCase durante os últimos dez anos, devido ao uso intensivo e frequente desses graminicidas para controlar plantas daninhas em lavouras de soja. Experimentos de dose-resposta realizados com a planta confirmaram a resistência de um biótipo. Houve elevada tolerância aos herbicidas, com fatores de resistência da ordem de 143 (fenoxaprop, 126 (haloxyfop, 84 (sethoxydim e 58 (fluazifop. Ensaios com a enzima ACCase in vitro indicaram a insensibilidade desta como a principal causa de suscetibilidade reduzida a esses herbicidas. Fragmentos de PCR gerados do domínio CT da enzima ACCase dos biótipos resistente e sensível de referência foram sequenciados e comparados. Foi detectada uma mutação dentro do tripleto de asparagina na posição do aminoácido 2078 (referente ao acesso número AJ310767 no EMBL, que resultou no tripleto de glicina. Esses resultados constituem o primeiro caso

  10. USO DE ENZIMAS EN LA CRÍA Y ENGORDE DE POLLOS BROILERS EN ÉPOCA LLUVIOSA EN LAS LOCALIDADES DE QUEVEDO, SALCEDO Y SANTO DOMINGO DE LOS COLORADOS

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    Ricardo Luna Murillo

    2010-12-01

    Full Text Available Con la finalidad de evaluar el uso de enzimas comerciales Ronozyme, SSF, VegPro e Hyboteck (Yucca schidigera en la cría y engorde de pollos broilers en época lluviosa se estableció un ensayo en tres provincias: Los Ríos (Quevedo, Santo Domingo de los Tsáchilas (Santo Domingo de los Colorados y Cotopaxi (Salcedo, utilizando un total de 1,440 aves de línea Hubbard (480 por localidad. Se empleó un Diseño Completamente al Azar, con cuatro tratamientos (enzimas y seis repeticiones con 20 pollos como unidad experimental. Las variables evaluadas fueron: consumo de alimento (g, ganancia de peso (g, conversión alimenticia, rendimiento a la canal (%, relación Costo/Beneficio y análisis bromatológicos de las canales. Se observó que los mayores consumo de alimento en las tres localidades se presentó con Hyboteck, (5,181.21; 6,713.42 y 5,680.37 g; la mejor ganancia de peso se observó con VegPro en Quevedo (2,543.34 g, SSF Santo Domingo de los Colorados (3,497.83 g e Hyboteck en Salcedo (2,286.08 g, la conversión más eficiente se reportó con Ronozyme en Quevedo (1.76, SSF en Santo Domingo de los Colorados (1.88, y VegPro en Salcedo (2.55. La mayor relación costo / beneficio se presentó con SSF en las localidades de Santo Domingo de los Colorados (0.10 y Salcedo (0.21 mientras en Quevedo la mejor fue Ronozyme (0.26. El mejor valor proteico de las canales de pollos se reportaron en las localidades de Quevedo y Salcedo con Ronozyme (26.05 y 22.80% respectivamente, y para la localidad de Santo Domingo de los Colorados fue con SSF (25.35% de proteína.

  11. Efeitos genotóxicos e alterações de enzimas hepáticas em trabalhadores do refino de petróleo Genotoxic effects and hepatic enzymes alterations among petroleum refinery workers

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    Rozana Oliveira Gonçalves

    2005-10-01

    Full Text Available Um estudo de casos e controles, aninhado num estudo de coorte, investigou a associação entre efeitos genotóxicos e alteração de enzimas hepáticas em trabalhadores de uma refinaria de petróleo do Nordeste. Foram examinados todos os dez novos casos de alterações de enzimas hepáticas - gama-glutamil transferase (GGT e alanina aminotransferase (ALT - ocorridos em 2002. Dez trabalhadores sem alterações de GGT ou ALT foram selecionados como controles. Os efeitos do fumo, sexo, idade e consumo de café foram controlados. O efeito genotóxico foi avaliado pela técnica de trocas entre cromátides irmãs (TCI e alterações cromossômicas (AC estruturais. As médias de TCI por célula (3,92 ± 1,04 versus 4,25 ± 1,47 e de ACE (8,85 ± 3,4 versus 9,1 ± 3,7 não diferiram de forma significante entre casos e controles respectivamente.A case-control study, nested in a cohort study, investigated the association between genotoxic effects and hepatic enzymes alterations among workers in a petroleum refinery, Northeast Brazil. Ten cases of hepatic enzymes alterations - gamma-glutamyltransferase (GGT and Alanine aminotransferase (ALT - representing all incident cases occurring in the refinery during 2002, were examined. Ten workers without GGT and ALT alterations were selected as controls. The effects of smoking, sex, age and coffee consumption were controlled. The genotoxic effects were evaluated by the sister chromatid exchange (SCE and by the chromosomal aberrations (CA techniques. Mean SCE per cell (3.92 ± 1.04 versus 4.25 ± 1.47 and CA per cell (8.85 ± 3.4 versus 9.1 ± 3.7 did not differ significantly between cases and controls respectively.

  12. Avaliação da celulase e pectinase como enzimas complementares, no processo de hidrólise-sacarificação do farelo de mandioca para produção de etanol Evaluation of the cellulase and pectinase by complementary enzymes in the process of hydrolysis-saccharification of cassava fibrous waste for alcohol production

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    Magali LEONEL

    1999-01-01

    Full Text Available Neste trabalho objetivou-se avaliar o uso de enzimas complementares no processo enzimático de hidrólise e sacarificação para a produção de etanol a partir do resíduo fibroso das fecularias. Os resultados obtidos demonstraram que 63,42% do amido foram hidrolisados no tratamento em que não se utilizaram enzimas complementares. No tratamento com as duas enzimas complementares foram hidrolisados 89,55%, no tratamento com celulase 65,42% e no tratamento com pectinase 88,73%. A prensagem do resíduo após o processo de hidrólise e sacarificação mostrou-se eficiente, ficando 10,43% do total de açúcares obtidos retidos no resíduo fibroso final. Portanto, o tratamento em que se utilizou a pectinase como enzima complementar na hidrólise foi o melhor. A celulase não apresentou efeito significativo no rendimento do processo.This work it was proposed to evaluate the use of complementary enzymes (cellulase and pectinase in the enzymatic process of hydrolysis-saccharification of the cassava fibrous waste for alcohol production. The results indicated that 63,42% of starch was hydrolyzed in the treatment without complementary enzymes, 89,55% in the treatment with the enzymes, 65,42% with the cellulase by complementary and 88,73% in the pectinase treatment. The pressing was efficacious for sugar recuperation and 10% of total sugar was retaining in the final fibrous residue. The pectinase was the better complementary enzyme enhance the yield.

  13. Technological application of an extracellular cell lytic enzyme in xanthan gum clarification Aplicação tecnológica de uma enzima celulolítica para clarificação de goma xantana

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    Suresh Shastry

    2005-03-01

    Full Text Available An extracellular cell lytic enzyme from Pseudomonas sp. was active on heat killed cells of Xanthomonas campestris. The lytic activity caused enzymatic digestion of X.campestris xanthan gum. Digestion was effective for highly viscous native xanthan 2.0% (w/v and 2.5% (w/v commercial Sigma xanthan. Scanning electron microscopy and SDS-PAGE observations confirmed the cell lytic action on X.campestris cells.Uma enzima extracelular celulolítica produzida por Pseudomonas sp. foi ativa sobre células de Xanthomonas campestris mortas pelo calor. A atividade lítica causou a digestão enzimática de goma xantana de X. campestris. A digestão foi eficiente tanto para xantana nativa altamante viscosa (2,0% w/v como para xantana comercial Sigma (2,5% w/v. Observações por microscopia eletrônica de varredura demonstraram a ação celulolítica sobre células de X. campestris.

  14. Metodologia de seleção de cepas para produção etodologia da ciclodextrina glicosiltransferase e para purificação da enzima - DOI: 10.4025/actascihealthsci.v29i1.133 Strains selection methodology for cyclodextrin glycosyltransferase production and enzyme purification - DOI: 10.4025/actascihealthsci.v29i1.133

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    Graciette Matioli

    2007-12-01

    Full Text Available As ciclodextrinas (CDs são maltooligossacarídeos, produzidas a partir do amido, pela enzima ciclodextrina glicosiltransferase (CGTase. Esta pesquisa teve por objetivo estabelecer metodologias de seleção de cepas para produção de CGTase e para purificação da enzima. Os microrganismos foram selecionados a partir de 53 análises de solos de cultura de amido, em placas contendo meio de cultivo específico, para seleção de cepas produtoras de CGTase. As enzimas foram obtidas com cultivo destes microrganismos em meio líquido. As atividades enzimáticas das CGTases foram determinadas pelos métodos espectrofotométricos e precipitação com tricloroetileno. A cepa isolada do solo de aveia foi a que apresentou maior atividade [0,1864 mol de -CD (min mL-1]. Esta cepa foi utilizada para a produção da enzima em escala laboratorial e purificação em cromatografia de afinidade bioespecífica. A cepa selecionada nesta pesquisa abre novas perspectivas para produção de enzima e CDs em escala industrial. Palavras-chave: ciclodextrina, glicosiltransferase, CGTase.Cyclodextrins (CDs are maltooligosaccharides produced from starch by cyclodextrin glycosyltransferase (CGTase enzyme. This research aimed at establishing method for strains selection for CGTase production and enzyme purification. The microorganisms were selected from 53 analyses of starch cultures soils on plates containing specific culture medium for strains selection that produce CGTase. The enzymes were obtained by culturing these microorganisms in liquid medium. The enzyme activity was determined with photospectrometric methods and precipitation with trichloroethylene. The strain isolated from oat soil was the one that showed the highest activity [0.1864 µmol of ß-CD (min mL-1]. This strain was used for enzyme production in laboratory scale and purification by biospecific affinity chromatography. The strain selected in this research opens new perspectives for enzymes

  15. Estudos de parâmetros que influenciam na produção da enzima CGTase de Bacillus firmus, cepa nº 37 Study of parameters that influence the production of the enzyme CGTase from Bacillus firmus, strain no. 37

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    Gisella Maria Zanin

    2000-05-01

    Full Text Available As ciclodextrinas (CDs são oligossacarídeos cíclicos formados por resíduos de glucopiranose unidos por ligação α-1,4. As mais comuns são α-, β- e γ-CD contendo 6, 7 e 8 resíduos de glucopiranose, respectivamente. Elas são produzidas a partir do amido pela ação da enzima ciclodextrina glicosiltransferase (CGTase. Freqüentemente, β-CD é produzida em maior quantidade. Um estudo da otimização da produção da CGTase de Bacillus firmus cepa nº 37 (β-CGTase foi realizado. A produção da enzima ocorreu durante a fase de crescimento exponencial do microrganismo e a máxima atividade foi observada com três dias de cultivo a 37ºC. O melhor rendimento na produção da enzima foi obtido quando da utilização de pré-inóculo com absorbância entre 0,5 e 1,0 (660 nm. O uso do substrato maltodextrina para produção da enzima proporcionou uma atividade enzimática ao redor de 31% menor que o substrato amido solúvel. Portanto, o substrato maltodextrina não é adequado para melhorar a produção da enzima estudada.The cyclodextrins (CDs are cyclic oligosaccharides formed by residues of glucopyranose linked by α-1,4. The most common are the α-, β- and γ-CD that present 6, 7 and 8 units of glucopyranose, respectively. They are produced from starch by the action of the enzyme cyclodextrin glycosyltransferase (CGTase. Frequently, β-CD is produced in larger amount. A study of optimization of the production of the CGTase from Bacillus firmus, strain no. 37 (β-CGTase was performed. The production of the enzyme occurred during the phase of exponential growth of the microorganism and the maximum activity was observed within three days of cultivation at 37ºC. The best production of the enzyme was obtained with inoculum of optical density between 0.5 and 1.0 (660 nm. The use of the maltodextrin for production of the enzyme provided an enzymatic activity at 31% lower than the substrate, soluble starch. Therefore, the substrate

  16. Efeito do cobre na atividade da enzima pirogalol peroxidase em plantas de Myriophyllum aquaticum cultivadas em solução nutritiva Effect of copper on the activity of pirogalol peroxidase in Myriophyllum aquaticum plants cultivated in nutritives solution

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    V.D. Domingos

    2005-06-01

    Full Text Available Myriophyllum aquaticum é uma planta perene, herbácea, que pode se desenvolver totalmente submersa ou com a porção terminal dos ramos acima da superfície da água. É também considerada uma planta daninha que possui elevado potencial de colonização, o qual, dependendo da densidade populacional, pode causar aumento no teor de matéria orgânica e redução de oxigênio na água, comprometendo a qualidade da água e seus usos múltiplos. O objetivo do presente trabalho foi verificar a influência do cobre na atividade da pirogalol peroxidase de plantas de M. aquaticum submetidas à solução nutritiva contendo concentrações de cobre de 1,2; 11,2; 21,2; 31,2; e 41,2 µg L-1. O experimento foi conduzido em um delineamento experimental inteiramente casualizado, com quatro repetições e cinco tratamentos, aos quais as plantas foram submetidas durante 21 dias. Aos 81 dias após a instalação das mudas em solução nutritiva contendo os diferentes níveis de cobre, as folhas foram colhidas a partir do ápice da planta até o final do ramo, que não estavam em contato com a solução. Esse material fresco foi envolvido por plástico transparente e papel-alumínio e, a seguir, congelado em nitrogênio líquido, sendo armazenado em freezer a -20 ºC até o momento da determinação da atividade da enzima pirogalol peroxidase. A atividade da enzima foi progressiva com o aumento das doses de cobre. As plantas cultivadas com 40 µg L-1 de Cu2+ após três semanas, com base em avaliação visual, apresentaram redução no desenvolvimento.Myriophyllum aquaticum is a perennial, herbaceous plant which grows totally submerged or with the terminal portion of the branches above the surface of the water. It is also considered to be a harmful plant, possessing a high colonization potential which, depending on population density, can increase the organic matter content and reduce oxygen in the water, compromising the quality of water and its multiple uses

  17. Efeito da alta pressão hidrostática na atividade de enzimas da polpa de açaí High hydrostatic pressure effect on enzyme activity of açai pulp

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    Ellen Mayra da Silva Menezes

    2008-12-01

    Full Text Available O Brasil vem conquistando o mercado externo de sucos de frutos tropicais, com destaque para o açaí, muito procurado por ser conhecido como um alimento funcional, devido à concentração de antocianinas, fibras dietéticas e ácidos graxos monoinsaturados. Entretanto, o açaí é altamente perecível, necessitando de intervenções tecnológicas para prolongar sua vida de prateleira. Nesse caso, o uso da Alta Pressão Hidrostática (APH pode ser uma alternativa aos processamentos tradicionais, por sua capacidade de ativar ou inativar enzimas. Peroxidases (POD e polifenoloxidases (PFO são as principais enzimas responsáveis por alterações indesejáveis das características originais de produtos vegetais e, com a sua inativação pela APH, pode-se evitar o escurecimento enzimático e manter as suas propriedades sensoriais. Com o objetivo de avaliar o efeito da APH em POD e PFO de polpa de açaí, adotaram-se as variáveis de pressão, temperatura e tempo. As atividades enzimáticas expressas em percentuais revelaram a POD mais estável, atingindo percentuais próximos a 100% (controle. As menores atividades foram a 90,74%, e quando se aplicaram 300 e 500 MPa a 25 °C por 5 minutos, as atividades aumentaram (112,34 e 132,98%, respectivamente. A atividade da PFO aumentou até 83,03% em relação ao controle, embora apresentasse inativação na maioria dos processos, evidenciando-se atividade a 35 °C/5 minutos de 53,25 e 53,75% a 300 e 500 MPa, respectivamente. Diante das condições experimentais, a APH mostrou-se eficaz na inativação parcial de oxidases na polpa de açaí.Brazil has been conquering tropical fruit juice international market , especially with açaí (native fruit with the highest penetration in the international, considered a functional food for its anthocyanin, dietetic fibe, and monounsaturated fat content. However, açaí is very perishable, so the use of technology is needed in order to ensure long shelf life. In this

  18. Enzimas de função hepática na aflatoxicose aguda experimental em frangos de corte Hepatic enzimes function in experimental acute enzimes aflatoxicosis in broilers

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    Adriana Borsa

    1998-12-01

    Full Text Available Com o objetivo de avaliar a função hepática de aves experimentalmente intoxicadas por aflatoxina, com e sem uso de bentonita sódica, foram utilizados 40 (quarenta frangos de corte, machos, linhagem Ross, divididos em 4 (quatro grupos de 10 (dez. animais, sendo que cada grupo foi submetido a um tratamento: T1 - controle (ração sem aflatoxina ou bentonita, T2 - ração com 5ppm de aflatoxina, T3 - ração com 5ppm de aflatoxina e 0,5% de bentonita sódica e T4 - ração com 0,5% de bentonita sódica. Todos estes tratamentos foram aplicados do 1° ao 42 ° dia de vida das aves. Aos 21, 35 e 42 dias de idade, foram analisados os níveis séricos das enzimas aspartato aminotransferase (AST, alanina aminotransferase (ALT, lactato desidrogenase (LDH e gama glutamiltransferase (GGT, A análise da variância mostrou que houve interação entre os tratamentos e datas de colheita de material, para as seguintes variáveis: AST, LDH e GGT. Para estas, foi aplicado o teste de Tukey, comparando-se as médias de cada tratamento em cada data. Observou-se que as enzimas AST, ALT e GGT não apresentaram diferenças significativas entre tratamentos, porém, nos tratamentos l e 2, a AST apresentou um aumento linear (pThe aim ofthis study is to evaluate ïhe hepatic function of experimentally intoxicated broilers by aflatoxin with and without sodium bentonite. Forty Ross mole broilers, were used divided into 4 groups of 10 birds, and such groups have been submitted to the following treatments: T1- control (feed without aflatoxin or sodium bentonite, T2- feed containing 5ppm of aflatoxin, T3- feed containing 5ppm of aflatoxin and 0.5% of sodium bentonite and T4- feed containing 0.5% of sodium bentonite. Ali these treatments have been appiied from the l st to the 42nd day of lif e. On the days 21, 35 and 42, the serum leveis of the enzimes aspartate aminotransferase (AST, alanino aminotransferase (ALT, lactate dehydrogenase (LDH and gamma glutamiltransferase (GGT

  19. Aparência, compostos fenólicos e enzimas oxidativas em uva 'Itália' sob influência do cálcio e do armazenamento refrigerado

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    LIMA MARIA AUXILIADORA COÊLHO DE

    2002-01-01

    Full Text Available O objetivo deste trabalho foi determinar o efeito da aplicação pré-colheita de cálcio na aparência (secamento do engaço, danos mecânicos e podridões, teor de fenólicos e enzimas oxidativas (polifenoloxidase e peroxidase em uva. Os cachos de uva 'Itália' de um cultivo comercial em Petrolina, Pernambuco, Brasil, foram marcados e imersos por 10 segundos, em soluções de Ca a 0 e 1,5%, na forma de cloreto de cálcio, aos 57 dias após o início da formação dos frutos (quando as bagas começaram a mudar de cor e amolecer. Após a colheita, os frutos foram armazenados a 3,5±0,2°C e 93±6% UR e avaliados aos 0; 14; 28; 42; 56 e 70 dias. Houve um incremento no secamento do engaço, no aparecimento de sintomas de danos mecânicos e de podridões nas bagas com o tempo de armazenamento. A aplicação de cálcio reduziu a atividade de polifenoloxidase e, conseqüentemente, os sintomas de danos mecânicos, resultando numa melhor aparência. A vida útil das uvas foi de aproximadamente 56 dias, quando sintomas de senescência, podridões e o nível dos sintomas de danos mecânicos começaram a aumentar de forma significativa.

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

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    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.

  1. Prevalencia del déficit de vitamina B12 en mayores de 60 años hospitalizados. Estudio del polimorfismo C677T de la enzima 5-10 MTHFR en pacientes con déficit de vitamina B12

    OpenAIRE

    Alonso Ortiz, María Belén

    2014-01-01

    Programa de doctorado: Avances en Medicina Interna. [ES] El déficit de Vitamina B12 es frecuente en los pacientes mayores. Sin embargo, son escasos los trabajos realizados en el ámbito hospitalario. Este déficit se asocia frecuentemente con elevación de la homocisteína plasmática, conocido factor de riesgo cardiovascular. Además la mutación C677T del gen de la enzima MTHFR se relaciona con hiperhomocistenemia, que puede coexistir con déficit de Vitamina B12, cuya frecuencia y consecuencias...

  2. Procedimiento para la extracción de gluten contenido en alimentos, procesados y no procesados por calor, compatible con un ensayo de inmunoabsorción ligado a enzimas, composición y kits que comprenden dicha composición

    OpenAIRE

    López Villar, Elena; Llorente Gómez, María de las Mercedes; Méndez Cormán, Enrique

    2001-01-01

    La presente invención se refiera a, en general, el análisis de alimentos para enfermos celiacos, y, especialmente, se refiere a un procedimiento para la extracción de gluten de alimentos, compatible con un ensayo de inmunoabsorción ligado a enzimas (ELISA), a composiciones adecuadas para la puesta en práctica de dicho procedimiento, a kits que comprenden dichas composiciones y a un procedimiento para la cuantificación por ELISA del gluten presente en los alimentos.

  3. Estudo e determinação teórica de propriedades físico-químicas de fármacos anti-hipertensivos inibidores da Enzima Conversora de Angiotensina

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    LUíZA REIS CRUZ

    2010-12-01

    Full Text Available O pacote de softwares SpartanTM vs 04 foi utilizado para calcular algumas propriedades físico-químicas de uma série de inibidores da Enzima Conversora de Angiotensinogênio ECA. Simultaneamente, o pacote MarvinSketch 5.0.0 foi empregado para calcular o Coeficiente de Partição P dos inibidores. Através da análise dos resultados, conclui-se que: a o arranjo termodinâmico mais estável desses inibidores mimetiza aquele dos resíduos pré-terminais da angiotensina II, b há grande similaridade entre as cargas dos átomos que se ligam à macromolécula e c os cálculos mostram diferenças significativas entre os valores de P para os inibidores. Portanto, as diferenças farmacológicas existentes entre os inibidores estão mais intimamente relacionadas ao coeficiente de partição do que à capacidade destes de inibir o sítio ativo da ECA. Palavras-chave: ECA. Ab initio. Equilíbrio conformacional. Lipofilicidade. ABSTRACT Theoretical study and determination of physicochemical properties of antihypertensive angiotensin-converting enzyme inhibitors The software package SpartanTM 4.0 was employed to calculate some physicochemical properties of a series of available ACE inhibitors. Simultaneously, the program MarvinSketch 5.0.0 was employed to calculate the partition coefficients (P of the same compounds. After analyzing the results, we conclude that: a from a thermodynamic point of view, the most stable conformer of each inhibitor resembles, as expected, the most stable spatial arrangement of the preterminal residues of angiotensin II; b there is great similarity among the charge profiles of the potential binding sites of all the inhibitors; c there are large differences in P among these compounds. Summing up, the pharmacological differences reported between the inhibitors are more closely linked to their lipophilic properties than to their capacity to block the ACE active center. Keywords: ACE. Ab initio. Conformational

  4. Ativação da enzima conversora de angiotensina no coração após infarto do miocárdio e suas repercussões no remodelamento ventricular

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    Mill José Geraldo

    1997-01-01

    Full Text Available OBJETIVO: Determinar as alterações de atividade da enzima conversora de angiotensina (ECA no coração com infarto do miocárdio (IM e comparar os efeitos do captopril e losartan em parâmetros morfológicos e funcionais de ratos com IM. MÉTODOS: O IM foi produzido em ratos Wistar por ligadura de ramos da artéria coronária esquerda. Os controles (Con foram submetidos a uma cirurgia fictícia. Animais com IM e Con foram tratados com captopril (30mg/kg/dia ou losartan (15mg/kg/dia e estudados 30 dias após, determinando-se a atividade da ECA nos ventrículos direito (VD e esquerdo (VE, as alterações hemodinâmicas e as concentrações de hidroxiprolina (OH-Pro e proteína total no VD e VE. RESULTADOS: A atividade da ECA aumentou no VD (+25% e VE (+70% após IM. A maior atividade foi observada na cicatriz fibrótica, onde atingiu cerca de 4,5 vezes a do músculo do VE que sobreviveu ao IM (420±68 vs 94±8nmoles/g/min; P<0,01. O IM determinou aumento da pressão diastólica final e hipertrofia do VD e VE. Captopril e losartan foram igualmente eficazes em atenuar a hipertrofia e o aumento da pré-carga. O captopril também atenuou o aumento de OH-Pro no VD e VE após IM. O IM reduziu a concentração de proteína principalmente no músculo de VE, efeito esse acentuado pelo captopril. CONCLUSÃO: A grande atividade da ECA na cicatriz deve produzir altas concentrações de angiotensina II (AII no sangue que drena da cicatriz. Os efeitos dos inibidores da ECA seriam decorrentes, principalmente, da redução de geração local de AII, e não de aumento de cininas, uma vez que captopril e losartan exerceram efeitos similares no remodelamento pós-infarto.

  5. AISLAMIENTO, CLONACIÓN Y EXPRESIÓN DE UNA ENZIMA LIPOLÍTICA DE Natronococcus sp. TC6, A PARTIR DE UNA LIBRERÍA GENÓMICA

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    Alberto López Barrera

    2017-01-01

    Full Text Available Los procesos biotecnológicos e industriales demandan de biocatalizadores robustos. Para conseguir este atributo, se recurre a la búsqueda de enzimas de microorganismos que naturalmente se han adaptado a ambientes inhóspitos. La generación de bibliotecas genómicas y el análisis genómico son herramientas moleculares poderosas para descubrir biomoléculas con características únicas y sobresalientes. Empleando el genoma fragmentado mecánicamente de un arquea halófila, Natronococcus sp. TC6, se construyó una genoteca de cósmidos, los cuales fueron usados para transformar a la cepa E. coli. En total, fueron generados 2181 clones, de los cuales, se seleccionaron seis con actividad lipolítica, ya que hidrolizaron ésteres de p-nitrofenilo como sustratos, en un medio de reacción conteniendo 2.5 M de NaCl. Las clonas que hidrolizaron ambos sustratos (clonas positivas fueron aisladas y los cósmidos fueron purificados y fragmentados para posteriores análisis enzimáticos. Los fragmentos de DNA de las clonas positivas, fueron subclonados y secuenciados. El análisis bioinformático de las secuencias obtenidas permitió identificar una tioesterasa putativa, la cual fue ligada en un vector de expresión, y éste utilizado para su introducción en células de E. coli BL21 para la producción de la proteína recombinante. La tioesterasa identificada posee 158 aminoácidos con un peso molecular de 15.4 kDa y con una similitud del 99% con el gene de la bacteria Stenotrophomonas maltophilia. La tioesterasa putativa de Natronococcus sp. TC6, presenta tres sitios altamente conservados como en S. maltophilia, posee dos motivos cercanos al extremo N-terminal, GHVNN y YXEXAR. También presenta una variante del pentapéptido involucrado en el sitio activo y característico de la mayoría de las éster hidrolasas, GXSXV.

  6. Estresse salino em duas variedades de cana-de-açúcar: enzimas do sistema antioxidativo e fluorescência da clorofila Salinity stress in two varieties of sugar cane: enzymes of the antioxidant system and chlorophyll fluorescence

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    Lilia Willadino

    2011-06-01

    Full Text Available O Brasil destaca-se por ser o maior produtor de cana-de-açúcar (Saccharum officinarum L. e por dominar todos os estágios da tecnologia de produção de açúcar e etanol. Atualmente se observa a expansão dessa cultura para a região semiárida brasileira, a qual apresenta solos propensos à salinização. O presente trabalho objetivou avaliar a resposta à salinidade de duas variedades de cana-de-açúcar. O ensaio foi implantado em casa de vegetação, em delineamento inteiramente casualizado, em esquema fatorial 2 x 8 com cinco repetições, correspondendo a duas variedades de cana-de-açúcar (RB867515 e RB863129 e oito níveis de NaCl (0; 25; 50; 75; 100; 125; 150; 200 mM de NaCl. A salinidade induziu aumento na fluorescência e diminuição na concentração de clorofila em ambas as variedades. A redução da clorofila, entretanto, foi maior na variedade RB867515. Observou-se, nesta mesma variedade, aumento da atividade da peroxidase do ascorbato (APX e da catalase (CAT, enquanto na variedade RB863129 ocorreu redução na atividade dessas enzimas. Esses resultados indicam que a variedade RB867515 apresenta um mecanismo mais eficiente na proteção da planta contra danos no aparato fotoquímico e contra a ação de espécies reativas de oxigênio, em particular o H2O2.Brazil is seen as being the largest producer of sugarcane (Saccharum officinarum L. and of mastering all stages in the production of sugar and ethanol. Currently this production is being expanded into the semi-arid regions of Brazil, where there are soil-types prone to salinity. This study aimed to evaluate the response to salinity in two sugarcane genotypes, RB867515 and RB863129. Salinity caused an increase in chlorophyll fluorescence and a reduction of chlorophyll concentration in both varieties. The reduction of chlorophyll however was higher in RB867515. In this same type, an increase in the activity of ascorbate peroxidase (APX and catalase (CAT was observed, while in

  7. Análise da atividade da enzima conversora da angiotensina na hipertrofia aguda do ventrículo direito em modelo experimental de estenose endovascular ajustável do tronco pulmonar

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    RABELLO Renato Rocha

    2001-01-01

    Full Text Available INTRODUÇÃO: A bandagem do tronco pulmonar (TP tem sido aplicada para treinamento do ventrículo esquerdo (VE em pacientes portadores de transposição das grandes artérias (TGA com septo íntegro. Este procedimento, além de apresentar alta morbi-mortalidade, pode ocasionar alterações da função ventricular a longo prazo. Com o objetivo de analisar a hipertrofia aguda do ventrículo direito (VD, foi implantado um cateter balão no TP de seis cabritos jovens. MATERIAL E MÉTODOS: A sobrecarga sistólica foi aplicada através de insuflações progressivas do balão, durante 96 horas. Esta hipertrofia foi acompanhada por medidas hemodinâmicas diárias, através de cateteres implantados na aorta, VD e TP, além de ecocardiogramas seriados a cada 24 horas, com medidas das espessuras do septo interventricular e dos ventrículos. Ao final das 96 horas, os animais foram mortos para remoção dos corações. Os ventrículos e o septo foram pesados separadamente. Foram colhidas biópsias musculares de cada câmara para análise da atividade da enzima conversora da angiotensina (ECA. Oito cabritos (idade e peso semelhantes foram utilizados como controle para os pesos dos ventrículos e para a atividade da ECA. RESULTADOS: Observou-se um aumento do gradiente VD/TP (p=0,001, com conseqüente aumento da razão VD/VE (p=0,005 durante o tempo de sobrecarga sistólica. Ao fim do protocolo, a parede livre do VD apresentou aumento de espessura (p=0,002 e, conseqüentemente, um aumento do peso indexado (p=0,002. A análise da atividade da ECA revelou aumento somente no músculo do VD hipertrofiado (p=0,002. CONCLUSÃO: O cateter balão foi eficiente em induzir a hipertrofia aguda do VD através do protocolo utilizado. Conseqüentemente, um aumento expressivo da atividade da ECA está associado ao processo de hipertrofia miocárdica induzida por sobrecarga pressórica.

  8. Treinamento aeróbio de natação aumenta a atividade de enzimas antioxidantes e o conteúdo de glicogênio no musculoesquelético de ratos

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    Roberto Carlos Vieira Junior

    2013-06-01

    Full Text Available INTRODUÇÃO: São escassos os estudos os quais verificaram os efeitos do exercício físico sobre os biomarcadores de estresse oxidativo e sua relação com o glicogênio muscular. OBJETIVO: O presente estudo verificou o efeito do treinamento aeróbio de natação (TAN sobre os biomarcadores de estresse oxidativo, conteúdo de glicogênio e crescimento celular no músculo esquelético de ratos. MÉTODOS: Dezoito ratos Wistar macho (60 dias foram divididos em dois grupos: Grupo Sedentário (SG; n = 10: ratos sedentários; e Grupo Treinado (TG; n = 8: ratos submetidos ao TAN (5,0 % do peso corporal, 1h/dia, 5X/semana, durante oito semanas. A atividade das enzimas antioxidantes (AEA superóxido dismutase (SOD; U/ml, catalase (CAT; µmol/min/100 mg e glutationa peroxidase (GPx; nmol/min/100 mg, bem como a concentração das substâncias que reagem ao ácido tiobarbitúrico (TBARs; nmolMDA/mg proteína foram determinadas no músculo gastrocnêmio direito. Os conteúdos de glicogênio (mg/100 mg, proteína (g/100 g e DNA (g/100 g foram mensurados no músculo gastrocnêmio esquerdo. RESULTADOS: A AEA foi maior no TG (CAT: 0,87 ± 0,04; SOD: 6,49 ± 0,045; GPX: 6,49 ± 0,52 quando comparados com SG (CAT: 0,52 ± 0,03; SOD: 4,1 ± 0,37; GPx: 2,94 ± 0,56. Os níveis de TBARs foram menores em TG (TG: 2,35 ± 0,41; SG: 8,90 ± 0,47. O conteúdo de glicogênio muscular (SG: 0,108 ± 0,013; TG: 0,320 ± 0,012 e a razão proteína/DNA (SG: 24,94 ± 3,25; TG: 41,68 ± 4,02 foram maiores no TG. CONCLUSÃO: Em conjunto, estes dados confirmam que o TAN melhorou a defesa antioxidante, a qual pode estar associada ao aumento do conteúdo de glicogênio no músculo esquelético dos animais.

  9. As enzimas no quotidiano: contextos de aprendizagem

    OpenAIRE

    Nunes, Ana Margarida Martins

    2010-01-01

    O presente trabalho propõe-se divulgar um conjunto de actividades sobre o tema “Fermentação e Actividade Enzimática”, desenvolvidas na disciplina de Biologia do 12ºano de escolaridade do Curso Científico-humanístico de Ciências e Tecnologias. Procurou-se demonstrar as vantagens da utilização do Jogo como oportunidade educativa de motivação e aprendizagem, através de actividades de Role-play, especialmente aplicadas ao trabalho prático de cariz experimental, no ensino das Ciências, uma área...

  10. Mice plasma fibrinogen consumption by thrombin-like enzyme present in rattlesnake venom from the North-East region of Argentina Consumo de fibrinógeno plasmático en ratones por acción de enzima con actividad trombínica presente en el veneno de cascabel del nordeste argentino

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    Silvana L. Maruñak

    2004-12-01

    Full Text Available Due to variability of venom components from the same species of snakes that inhabit different regions, particular properties of the venom of Crotalus durissus terrificus that inhabits the North-East of Argentina were studied. Gyroxin, a thrombin-like enzyme, was isolated from this venom by gel filtration and affinity chromatography, it was found to be homogeneous according to SDS-PAGE, with a molecular weight of 33 kDa. "Gyroxin syndrome" in mice was tested and it showed changes in the animal behavior, confirming that the isolated thrombin-like enzyme is gyroxin. Effects of this enzyme and the crude venom on mice plasmatic fibrinogen levels were determined. The mice plasma fibrinogen decreased rapidly until incoagulability during the first hour after thrombin-Iike enzyme injection, then reaching its normal level 10 hours after injection; whereas crude venom resulted in a 60% decrease of the mice plasma fibrinogen, reaching its normal level after the same period of time. After 1 hour of gyroxin inoculation, intravascular coagulation was observed in histological cuttings of lung, cardiac muscle and liver. The isolated enzyme showed strong hydrolyzing activity on fibrinogen and fibrin in vitro, whereas the crude venom exhibited weak hydrolyzing activity on both substrates. It is probable that this very low activity is due to the low percentage of the enzyme in the crude venom. Decreasing of plasmatic fibrinogen levels may be due to either the coagulant or hydrolyzing actions of the enzyme.Teniendo en cuenta la variabilidad de los componentes del veneno de serpientes de una misma especie que habitan regiones diferentes, se decidió estudiar las propiedades particulares del veneno de Crotalus durissus terrificus que habita el nordeste de Argentina, Giroxina, una enzima con actividad trombínica, fue aislada del veneno por cromatografía de filtración por gel y de afinidad; se comprobó su homogeneidad y se determinó su peso molecular, 33 kDa, por

  11. OBTENÇÃO E UTILIZAÇÃO DA ENZIMA POLIFENOLOXIDASE EXTRAÍDA DE POLPA DE PINHA (Annona squamosa L. MADURA NO MELHORAMENTO DO SABOR DO CACAU (Theobroma cacao L. OBTAINING AND USE OF POLYPHENOLOXIDASE ENZYME EXTRACTED FROM RIPE CUSTARD APPLE (Annona squamosa L. PULP ON THE COCOA (Theobroma cacao L. NIBS IN TASTE IMPROVEMENT

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    ELIZA DOROTEA POZZOBON DE ALBUQUERQUE LIMA

    2001-12-01

    Full Text Available O presente trabalho teve como objetivo estudar a obtenção e a utilização da enzima polifenoloxidase (PPO extraída de polpa de pinha madura na redução do teor de compostos polifenólicos com a finalidade de diminuir a adstringência e o amargor das amêndoas de cacau processadas na forma de "nibs". A PPO foi extraída com tampão fosfato de potássio 0,025M (pH 7,5, adicionando sulfato de amônio para a precipitação da enzima. O material em pó obtido foi denominado de enzima parcialmente purificada, sendo que a análise de atividade enzimática foi realizada, utilizando-se de catecol como substrato. As características bioquímicas apresentadas foram pH de estabilidade de 6,0 a 6,5 e temperatura de estabilidade de 10 a 30°C. Os "nibs" foram autoclavados (121°C por 15 minutos e não autoclavados de amêndoas cruas insuficientemente fermentadas e secas, da mesma origem, sendo embebidas em 25 mL de uma solução da enzima contendo 200 unidades/min/mL, durante 30; 60; 90; 210 e 360 minutos, a 23°C e pH 6,0. Os "nibs" foram homogeneizados com a solução de enzima a cada 15 minutos, secos, moídos e desengordurados. Após o tratamento enzimático durante 210 minutos realizado nos "nibs" de cacau desengordurado não autoclavados foi possível observar diminuição de 15% nas concentrações de fenóis totais, 15% de taninos, 10% de flavan-3-ois e 18% de antocianidinas. Os "nibs" de cacau desengordurado autoclavados apresentaram diminuição de 25% nas concentrações de fenóis totais, 26% de taninos, 23% de flavan-3-ois e 51% de antocianidinas.The present work had as aim to study the obtaining and the uses of polyphenoloxidase enzyme (PPO extracted from ripe custard apple pulp on the reduction of polyphenolic compounds with decrease adstringency and bitterness of cocoa nuts processed at nibs form. The PPO was extracted with 0.025M potassium phosphate buffer (pH 7.5, adding ammonium sulfate to the enzyme precipitation. The powdered

  12. Topical estradiol does not interfere with the expression of the metalloproteinase-1 enzyme in photo exposed skin cells Estradiol tópico não interfere na expressão da enzima metaloproteinase-1 em células da pele fotoexposta

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    Luciana Neder

    2012-02-01

    Full Text Available BACKGROUND: In postmenopausal women there is a rapid destruction of dermal collagen, resulting in accelerated skin ageing, which is manifested by cutaneous atrophy, increased number and depth of wrinkles and sagging. This accelerated catabolism of the collagen is due to estrogen deficiency and increased synthesis of the metalloproteinase-1 enzyme, which degrades the dermal collagen. OBJECTIVES: To assess whether the use of topical estradiol 0.05% cream on photo exposed skin can inhibit the expression of the metalloproteinase-1 enzyme on the dermis and subsequently the rapid loss of collagen in women after menopause. METHODS: We included 40 postmenopausal women without hormone replacement therapy. Information about lifestyle, lipid profile, blood glucose level, thyroid hormones, mammography, Pap smear and transvaginal ultrasound were obtained to rule out associated diseases. Skin biopsy of the right preauricular region was performed before and after treatment with topical estradiol 0.05% for 30 days. The biopsy specimens were subjected to immunohistochemistry to identify the expression of the metalloproteinase-1 enzyme. RESULTS: There was no statistically significant difference on the expression of the metalloproteinase-1 enzyme in keratinocytes, fibroblasts and endothelial cells before and after treatment with topical estradiol for 30 days. CONCLUSION: Treatment with estradiol 0.05% cream, in photo exposed skin for 30 days, does not inhibit the production of metalloproteinase-1.FUNDAMENTOS: Na pós-menopausa, ocorre rápida destruição do colágeno dérmico, com consequente envelhecimento acelerado da pele, que se expressa com atrofia cutânea, aumento do número e da profundidade das rugas e flacidez. Esse catabolismo acelerado do colágeno ocorre por deficiência estrogênica e aumento na síntese da enzima metaloproteinase-1, que degrada o colágeno dérmico. OBJETIVOS: Avaliar se o uso de estradiol tópico a 0,05% em creme na pele

  13. Enzymatic antioxidant responses to biostimulants in maize and soybean subjected to drought Respostas de enzimas antioxidantes a bioestimulantes em plantas de milho e de soja sob estresse hídrico

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    Ana Carolina Feitosa de Vasconcelos

    2009-06-01

    Full Text Available Water stress is one of the most important environmental factors inducing physiological changes in plants, such as decrease in the water potential of the cells, the stomatal closure; and the development of oxidative processes mediated by reactive oxygen species (ROS. Antioxidant enzymes superoxide dismutase (SOD, catalase (CAT, and ascorbate peroxidase (APX are efficient scavengers of ROS. The aim of this research was to examine how the application of biostimulant based on humic substances and aminoacids may affect activity levels of SOD, CAT, and APX of maize and soybean plants under well-watered or drought stress conditions. Pots (4.5 L were filled with a Typic Hapludult soil where the biostimulants doses were applied. It was taken leaf samples in order to analyze SOD, CAT, and APX activities in plants. SOD and APX activity levels were increased by application of biostimulant 1 in maize subjected to stress. Catalase activity was not enhanced in plants by using the biostimulants. The composition of the biostimulants was not able to enhance stress tolerance in maize and soybean plants subjected to water stress.O estresse hídrico é um dos mais importantes fatores ambientais que induz mudanças fisiológicas, como diminuição do potencial de água na célula, o fechamento dos estômatos e o desenvolvimento de processos oxidativos mediante a formação das espécies reativas de oxigênio (ROS. As enzimas antioxidantes superóxido dismutase (SOD, catalase (CAT e ascorbato peroxidase (APX são eficientes eliminadores das ROS. O objetivo deste estudo foi examinar como a aplicação de bioestimulantes com substâncias húmicas e aminoácidos em sua composição afeta os níveis de SOD, CAT e APX nos tecidos das folhas de plantas de milho e de soja cultivadas com ou sem estresse hídrico. Amostras de um Argissolo foram colocadas em vasos (4,5 L onde foram adicionadas as doses dos bioestimulantes. Foram retiradas amostras de folhas para análise da

  14. Are the angiotensin-converting enzime gene and acticity risk factors for stroke? São fatores de risco para acidente vascular cerebral o gene e a atividade da enzima conversora de angiotensina ?

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    Miris Dikmen

    2006-06-01

    Full Text Available Stroke is a multifactorial disease in which genetic factors play an important role. This study was carried out to determine angiotensin-converting enzyme (ACE gene polymorphism in Turkish acute stroke patients and to establish whether there is an association of angiotensin-converting enzyme gene I/D polymorphism with clinical parameters. In this study 185 patients and 50 controls were recruited. We have investigated the association among the allelic distribution of the insertion/deletion (I/D polymorphism of the ACE gene identified by polymerase chain reaction. Distribution of ACE gene I/D genotypes and allele frequencies in patients were not significantly different from controls. D allele frequencies were 57.8% in patients versus 53.0% in controls and I allele 42.2% versus 47% respectively. History of hypertension, stroke, renal, heart and vessel diseases incidence and age, gender, systolic-diastolic blood pressures and creatinine levels were significantly high in patients. But these results and ACE activities had no significant differences among the ACE genotypes in patients and controls. Our results suggest that the ACE gene polymorphism is not associated with the pathogenesis of stroke in Turkish stroke patients.O acidente vascular cerebral (AVC é doença multifatorial em que fatores genéticos desempenham papel importante. Este estudo foi desenvolvido para verificar o polimorfismo do gene da enzima conversora da angiotensina (ECA em pacientes turcos com AVC agudo e estabelecer se existe associação do gene I/D da ECA com parâmetros clínicos. O estudo foi realizado com 185 pacientes e 50 controles. A associação entre a distribuição alélica da inserção / deleção (I/D do polimorfismo do gene da ECA foi estudada pela reação em cadeia da polimerase. A distribuição dos genótipos I/D do gene da ECA e suas freqüências não apresentaram significância estatística quando comparados os pacientes e controles. As freqüências dos

  15. Study of association between genetic polymorphisms of phospholipase A2 enzymes and Alzheimer's disease Associação entre polimorfismos das enzimas fosfolipases A2 e doença de Alzheimer

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    Quirino Cordeiro

    2010-04-01

    Full Text Available Several genes have been related to late-onset Alzheimer's disease (LOAD. Phospholipases A2 (PLA2 influence the processing and secretion of the amyloid precursor protein, which gives rise to the beta-amyloid peptide, the major component of the amyloid plaque in AD. Hence, in the present study, polymorphisms of three genes encoding PLA2 enzymes group (cytosolic PLA2: BanI cPLA2 polymorphism; calcium-independent PLA2: AvrII iPLA2 polymorphism; PAFAH: Val279Phe PAFAH polymorphism were analysed in a case-control sample using 58 patients with LOAD and 107 matched healthy controls. There was a genotypic association between the BanI cPLA2 polymorphism and LOAD (χ2=6.25, 2df, p=0.04, however there was no allelic association. There were no associations between AvrII iPLA2 and Val279Phe PAFAH polymorphisms and LOAD. These data suggest that the BanI cPLA2 polymorphism may play a role in the susceptibility for LOAD in our Brazilian sample.Vários genes têm sido investigados como fatores de risco para o desenvolvimento da doença de Alzheimer (DA de início tardio. As fosfolipases A2 (PLA2 influenciam o processamento e secreção da proteína precursora do amilóide, que dá origem ao peptídeo meta-amilóide, o principal componente da placa amilóide na DA. Assim, no presente estudo, foram analisados três polimorfismos genéticos que codificam enzimas do grupo das PLA2 (PLA2 citosólica: polimorfismo BanI cPLA2; PLA2 cálcio-independente: polimorfismo AvrII iPLA2; PAFAH: polimorfismo Val279Phe PAFAH em 58 pacientes com DA de início tardio e 107 controles saudáveis pareados. Houve associação genotípica entre o polimorfismo BanI cPLA2 e DA de início tardio (χ2=6,25, 2df, p=0,04; no entanto não foi observada associação alélica. Não houve associação entre os polimorfismos AvrII iPLA2 e Val279Phe PAFAH com a doença. Tais dados sugerem que o polimorfismo BanI cPLA2 pode estar envolvido como fator de susceptibilidade para DA de início tardio em

  16. Utilização de enzimas proteolíticas para produção de hidrolisados proteicos a partir de carcaças de frango desossadas manualmente

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    Mari Silvia Rodrigues de OLIVEIRA

    2015-09-01

    Full Text Available Resumo O emprego de hidrolisados proteicos, oriundos de fontes animais e vegetais, em formulações específicas, é uma área de crescente interesse. O objetivo deste trabalho foi desenvolver diferentes hidrolisados liofilizados com alto valor proteico, obtidos a partir da hidrólise enzimática de carcaças de frango manualmente desossadas (CMD, um subproduto da indústria avícola, que normalmente é utilizado para a fabricação de carne mecanicamente separada (CMS. A matéria-prima utilizada foram carcaças de frango desossadas manualmente e congeladas (CMD, provenientes de animais abatidos com aproximadamente 42 dias de vida e com peso médio de 2,5 kg, adquiridas em um abatedouro da região sul do Brasil. Antes de serem processadas, foram descongeladas sob temperatura de refrigeração e cortadas em pedaços menores com faca de aço inox para facilitar sua homogeneização durante o tempo de hidrólise. Foram utilizadas três enzimas comerciais, Papaína®, Flavourzyme® e Protamex®. A hidrólise ocorreu em banho termostatizado com temperatura, tempo e pH controlados. Foi realizada a composição proximal da matéria-prima e dos hidrolisados liofilizados, atividade de água dos hidrolisados liofilizados e foram feitas as seguintes análises de controle da hidrólise: grau de hidrólise, teores de proteínas, sólidos totais, cinzas, caracterização de aminoácidos dos hidrolisados, rendimento, percentual de hidrólise e cor dos hidrolisados. Os resultados foram submetidos à análise de variância e teste de Tukey para comparação de médias. O grau de hidrólise maior foi com a Protamex, seguido da Papaína e da Flavourzyme. O teor de proteínas após os 120 minutos de hidrólise não variou estatisticamente (p>0,05 entre a Papaína e a Flavourzyme. A composição de aminoácido demonstra que o hidrolisado obtido da Papaína possui uma composição mais próxima da recomendada pelos órgãos de controle. Concluiu-se que os

  17. Hipotensão arterial em cirurgia de revascularização do miocárdio: influência dos inibidores da enzima conversora de angiotensina Hipotensión arterial en cirugía de revascularización del miocardio: influencia de los inhibidores de la enzima conversora de angiotensina Arterial hypotension in myocardial revascularization surgery: influence of angiotensin-converting enzyme inhibitors

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    Míriam Gomes Jordão

    2002-04-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Os inibidores da enzima conversora da angiotensina (IECA são drogas muito utilizadas em estados hipertensivos e insuficiência cardíaca. Seu uso prolongado pode acarretar instabilidade hemodinâmica com episódios hipotensivos durante a indução anestésica. O objetivo deste estudo é comparar a incidência de hipotensão arterial em pacientes cronicamente tratados com IECA com pacientes não tratados com IECA, quando submetidos à anestesia para cirurgia de revascularização do miocárdio. MÉTODO: Participaram do estudo 50 pacientes, estado físico ASA II, III e IV, divididos em dois grupos: Grupo 1 - pacientes tratados com IECA por mais de dois meses e Grupo 2 - pacientes que não fazem uso de IECA. Os parâmetros avaliados foram pressão arterial média (PAM, freqüência cardíaca (FC, sendo anotados os menores valores da PAM e FC verificados em diferentes períodos da anestesia, e análise do segmento ST em D II e V5. Durante a CEC, foi determinada a resistência vascular sistêmica. RESULTADOS: A incidência de hipotensão arterial em pacientes anestesiados em uso de IECA foi maior do que no grupo controle em vários períodos da anestesia, mas principalmente na indução anestésica. Neste grupo foi necessário o uso de dopamina por tempo mais prolongado. Dos 26 pacientes tratados previamente com IECA, 23% necessitaram de drogas para correção da hipotensão desde a indução até a CEC e 19,1% em outros períodos da anestesia, perfazendo um total de 42,3%. No grupo controle nenhum paciente necessitou infusão contínua de drogas para aumentar a pressão arterial sistêmica, da indução até a CEC. Porém, 21% dos pacientes deste grupo necessitaram dopamina ou araminol em um ou mais períodos da anestesia. CONCLUSÕES: Neste estudo, os pacientes tratados com IECA, por tempo prolongado, apresentam maior incidência de hipotensão arterial na indução anestésica, necessitando, com maior freqüência, de

  18. Caractérisation biochimique et fonctionnelle de glutathion-S-transferases (GSTs) chez Phanerochaete chrysosporium

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    Anak-Ngadin, Andrew

    2011-01-01

    Phanerochaete chrysosporium est un champignon ligninolytique largement étudié pour ses capacités à dégrader la lignine et certains xénobiotiques grâce à un important système d'enzymes extracellulaires. Son génome est entièrement séquencé et constitue un inventaire de séquences protéiques prédites qui a permis la description de nombreuses superfamilles de protéines. Parmi elles, les Glutathion S-transférases sont essentiellement impliquées dans le métabolisme secondaire du champignon. Cependan...

  19. Transcrição reversa na determinação da expressão do mRNA para a enzima conversora de angiotensina testicular em animais tratados com zinco Assessment of the reverse transcriptase polymerase chain reaction technique in the determination of the mRNA expression for the testicular angiotensin-converting enzyme in zinc treated rats

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    Gilberto Simeone Henriques

    2005-12-01

    Full Text Available OBJETIVO: O objetivo deste trabalho foi otimizar as condições reacionais capazes de ocasionar variabilidade e de introduzir erros sistemáticos na reação em cadeia pela polimerase aplicada à análise da expressão gênica da isoforma testicular da enzima conversora de angiotensina. MÉTODOS: Avaliaram-se a concentração de cDNA, a concentração dos iniciadores, a temperatura de hibridização e o número de ciclos de desnaturação, hibridização e extensão. Para tanto, extraiu-se o RNA total por meio da reação com fenol-clorofórmio e isotiocianato de guanidina de amostras de testículos de ratos Wistar alimentados com uma ração contendo zinco. Em seguida, gerou-se o cDNA por transcrição reversa. Utilizando-se iniciadores específicos, amplificaram-se o gene de interesse (isoforma testicular da enzima conversora de angiotensina e o gene controle Gliceraldeído-3-Fosfato-Desidrogenase. As amostras foram então aplicadas em gel de agarose e submetidas à eletroforese, coradas em brometo de etídio e visualizadas sob luz ultravioleta. RESULTADOS: Demonstrou-se que a melhor condição reacional para a reação em cadeia pela polimerase da isoforma testicular da enzima conversora de angiotensina e do Gliceraldeído-3-Fosfato-Desidrogenase foi: (1 concentração inicial de cDNA de 2µg, (2 concentração de iniciadores de 200nM, (3 temperatura de hibridização entre 57,5ºC e 60,1ºC e (4 33 ciclos. CONCLUSÃO: Com essa otimização pôde-se minimizar as interferências sobre a técnica, contribuindo-se para a obtenção de dados comparativos a respeito da expressão gênica da enzima conversora de angiotensina testicular.OBJETIVE: The aim of the present work was to optimize the reaction conditions capable of generating variability and introducing systematic errors in the chain reaction of the polymerase used to analyze the gene expression for the testicular isoform of the angiotensin-converting enzyme. METHODS:The cDNA concentration

  20. Purification of a membrane-bound trypsin-like enzyme from the gut of the velvetbean caterpillar (Anticarsia gemmatalis Hübner =Purificação de uma enzima “tipo tripsina” não-solúvel do intestino da lagarta da soja (Anticarsia gemmatalis Hübner

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    Marcelo Matos Santoro

    2012-07-01

    Full Text Available Disruption of protein digestion in insects by specific endoprotease inhibitors is being regarded as an alternative to conventional insecticides for pest control. To optimize the effectiveness of this strategy, the understanding of the endoprotease diversity of the target insect is crucial. In this sense, a membrane-bound trypsin-like enzyme from the gut of Anticarsia gemmatalis fifth-instar larvae was purified. Non-soluble fraction of the gut extract was solubilized with 3-[(3-cholamidopropyldimethylammonio]-1-propanesulfonate (CHAPS and subjected to a p-aminobenzamidine affinity chromatography followed by anion-exchange chromatography. The yield of the purified enzyme was 11% with a purification factor of 143 and a final specific activity of 18.6 µM min.-1 mg-1 protein using N-α-benzoyl-L- Arg-p-nitroanilide (L-BApNA as substrate. The purified sample showed a single band with proteolytic activity active and apparent molecular mass of 25 kDa on SDS-PAGE. Molecular mass determined by MALDI-TOF mass spectrometry was 28,632 ± 26 Da. Although the low recovery and the difficulties in purifying large enzyme amounts limited its further characterization, the results contribute for the understanding of the proteases present on A. gemmatalis gut, which are potential targets for natural or specifically designed protease inhibitors.Comprometer a digestão de proteínas dos insetos pelo uso de inibidores específicos de endoproteases tem sido amplamente estudado como um método de controle de pragas alternativo ao uso dos inseticidas convencionais. No processo de otimização desta estratégia, o conhecimento da diversidade das endoproteases do inseto alvo torna-se crucial. Neste sentido, uma enzima “tipo-tripsina” ligada à membrana obtida do intestino de larvas do 5° instar de A. gemmatalis foi purificada. A fração insolúvel do extrato do intestino foi solubilizada com 3-[(3-cholamidopropyldimethylammonio]-1-propanesulfonate (CHAPS e submetida

  1. Acetylcholinesterase enzyme activity in carp brain and muscle after acute exposure to diafuran Atividade da enzima acetilcolinesterase em cérebro e músculo de carpas após exposição aguda ao diafuran

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    Jaqueline Ineu Golombieski

    2008-01-01

    idella, Valenciennes, 1844 e carpa cabeça grande (Aristichthys nobilis, Richardson, 1845 foram expostos ao diafuran, um inseticida utilizado na cultura do arroz no sul do Brasil. O objetivo deste estudo foi verificar a relação entre concentração letal mediana (CL50 do diafuran e a atividade da enzima acetilcolinesterase (AChE em cérebro e músculo dessas espécies, como um possível biomarcador inicial da exposição a este inseticida. A CL50 foi determinada com peixes expostos a concentrações de diafuran em 96 h: carpa húngara: controle; 0,5; 1,0; 1,5; 2,0; 2,5 e 3,0 mg L-1; carpa capim: controle; 1,0; 2,0; 3,0 e 3,5 mg L-1 e carpa cabeça grande: controle; 0,5; 1,0; 1,5; 2,0; 3,0 e 4,0 mg L-1, bem como a determinação da AChE em concentrações próximas da CL50 para essas espécies. Valores de CL50 (concentrações nominais foram de 1,81 mg L-1 para carpa húngara, 2,71 mg L-1 para carpa capim e 2,37 mg L-1 para carpa cabeça grande. Todas as carpas expostas ao diafuran estavam letárgicas (menores concentrações ou imóveis. Diafuran inibiu significativamente a atividade da AChE em cérebro (~38 % e músculo (~50 % de todas as espécies estudadas. Atividade da AChE em músculo para carpa cabeça grande foi mais alta que cérebro (14,44 contra 5,94 µmol min-1 g proteína-1, respectivamente. Este estudo demonstrou que concentrações de diafuran utilizadas na cultura do arroz podem afetar o comportamento de Cyprinus carpio, Ctenopharyngodon idella e Aristichthys nobilis, e a atividade da acetilcolinesterase cerebral e muscular pode ser um biomarcador inicial de toxicidade deste inseticida.

  2. Produção de etileno e atividade da enzima ACCoxidase em frutos de maracujá-amarelo (Passiflora edulis f. flavicarpa Deg. Ethylene production and ACCoxidase activity in passion fruits (Passiflora edulis f. flavicarpa Deg.

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    Larissa Macedo Winkler

    2002-12-01

    Full Text Available O maracujá-amarelo (Passiflora edulis f. flavicarpa Deg. é uma das principais espécies cultivadas do gênero Passiflora. Seus frutos são ricos em minerais, vitaminas e apresentam aroma e sabor agradáveis. O presente trabalho teve como objetivos determinar a produção de etileno e atividade enzimática da ACCoxidase (ACCO em maracujá-amarelo colhido em diferentes estádios de maturação. A determinação do estádio de maturação foi realizada com o auxílio de um colorímetro, que, por meio da radiação ultravioleta, estabeleceu valores absolutos da cor dos frutos de cada um dos grupos (I, II e III. A produção de etileno e a atividade da ACCoxidase foram realizadas por cromatografia gasosa. Os frutos do grupo I são predominantemente verdes, de acordo com os valores absolutos da cor obtidos. Os frutos do grupo II são predominantemente, coloridos, ou seja, em um estádio de maturação intermediário, e os frutos do grupo III, totalmente coloridos, apresentando-se, portanto, em início da senescência. Os frutos do grupo I apresentaram atividade da ACCO predominantemente mais elevada do que os frutos do grupo III, ocorrendo também o mesmo comportamento com a produção de etileno, com um valor médio de 7,25 nL. g-1. h-1, bem acima do nível máximo estabelecido para espécies classificadas como fracamente produtoras de etileno (0,5 nL. g-1. h-1. Assim, o maracujá-amarelo difere quanto à produção de etileno e atividade da enzima ACCO, de acordo com o estádio de maturação. A espécie foi considerada, em comparação com outras espécies, como produtora intermediária de etileno. A atividade enzimática da ACCO é mais elevada em frutos predominantemente verdes, mas ela é limitada e necessita de co-fatores enzimáticos para sua atividade máxima.Passion fruit (Passiflora edulis f. flavicarpa Deg. is one of the main cultivated species of Passiflora genus. Its fruits are rich in mineral salts and vitamins and to present

  3. Resistência de biótipos de Euphorbia heterophylla l. Aos herbicidas inibidores da enzima ALS utilizados na cultura de soja Resistance of Euphorbia heterophylla l. Biotypes to ALS enzyme inhibitor herbicides used in soybean crop

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    GERSON AUGUSTO GELMINI

    2001-01-01

    Full Text Available Os herbicidas constituem-se na principal medida de controle de plantas daninhas na cultura de soja; no entanto, a pressão de seleção causada pelo uso contínuo de produtos com o mesmo mecanismo de ação pode provocar a seleção de biótipos resistentes, como ocorreu com Euphorbia heterophylla L., que se mostrou resistente aos herbicidas inibidores da enzima acetolactato sintase (ALS em áreas dos Estados do Paraná e Rio Grande do Sul. Para comprovar possíveis novos casos, bem como alternativas para prevenção e manejo, coletaram-se sementes de plantas de E. heterophylla L., na região de Assis (SP, que sobreviveram a tratamentos, em que esses herbicidas foram sistematicamente aplicados nos últimos anos. Desenvolveu-se o experimento em casa de vegetação, comparando-se o biótipo resistente ao suscetível, quando submetido aos diversos herbicidas aplicados em pós-emergência. Aplicaram-se quando as plantas encontravam-se no estádio de duas a quatro folhas verdadeiras, nas doses zero, uma, duas, quatro e oito vezes a recomendada. Aos 20 dias após a aplicação, avaliaram-se os parâmetros relativos ao controle e produção de fitomassa epígea visando ao estabelecimento de curvas de doses-resposta, à obtenção dos fatores de resistência com base nos valores da DL50 e GR50, e à verificação da ocorrência de resistência múltipla. O biótipo resistente apresentou diferentes níveis de resistência aos herbicidas chlorimuron-ethyl e imazethapyr, demonstrando resistência cruzada aos inibidores da ALS dos grupos das sulfoniluréias e imidazolinonas. No entanto, foi eficientemente controlado nos tratamentos com fomesafen (250 g.ha-1, lactofen (120 g.ha-1, flumiclorac-pentil (40 g.ha-1, glufosinato de amônio (150 g.ha-1 e glyphosate (360 g.ha-1.Herbicides are the main tool for weed control in soybean crop, but the selection pressure attributed to the repeated application of the same herbicides and the same mechanism of action can

  4. Frecuencia de enzimas asociadas a sensibilidad disminuida a betalactámicos en aislados de enterobacterias, Caracas, Venezuela Frequency of enzymes associated with reduced sensitivity to beta-lactam antibiotics in enterobacteria isolates, Caracas, Venezuela

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    Daniel Marcano

    2011-12-01

    Full Text Available OBJETIVO: Determinar la frecuencia de los mecanismos enzimáticos asociados a sensibilidad disminuida a los antibióticos betalactámicos de amplio espectro en aislados de enterobacterias obtenidos de centros hospitalarios de Caracas, Venezuela. MÉTODOS: Se realizó un estudio transversal con enterobacterias aisladas de pacientes de ocho centros hospitalarios de Caracas, Venezuela, desde el 15 de octubre de 2009 al 15 de enero de 2010. La identificación se realizó mediante pruebas bioquímicas convencionales, y la susceptibilidad a los antimicrobianos mediante antibiograma (Kirby-Bauer, según las normas de 2010 del Instituto de Estándares Clínicos y de Laboratorio. La detección de los genes de resistencia a betalactámicos se realizó mediante amplificación por reacción en cadena de polimerasa. RESULTADOS: De 1 235 aislados, 207 (16,8% mostraron resistencia a cefalosporinas de tercera y cuarta generación o a carbapenemes o a ambos. De esos, 93,8% presentaron fenotipo betalactamasa de espectro extendido (BLEE; 4,3%, fenotipo AmpC derreprimido, y 1,9%, fenotipo carbapenemasa. La caracterización de los dos primeros fenotipos determinó que 36,7% eran tipo SHV; 22,3%, grupo CTX-M-1; 21,7%, tipo TEM; 5,2%, grupo CTX-M-1 + impermeabilidad; 4,5%, combinación de dos enzimas; 4,3%, grupo CTX-M-2; 3,4%, tipo PER, y 1,9%, tipo KPC. Se observó un predominio del tipo SHV en las cepas obtenidas de hospitales públicos y del grupo CTX-M-1, en los privados. CONCLUSIONES: De los mecanismos enzimáticos investigados, el tipo SHV fue el más frecuente, seguido del grupo CTX-M-1 y tipo TEM. Asimismo, se encontró un alto porcentaje de carbapenemasas tipo KPC. Este es uno de los pocos estudios multicéntricos realizados en Venezuela donde se evalúa la frecuencia de este tipo de mecanismo de resistencia a los antimicrobianos, incluida la caracterización fenotípica y molecular. Se demostró que los métodos de detección requieren una interpretaci

  5. ENZIMAS LIPOLITICAS DE KRILL ANTARTICO: PURIFICACION Y CARACTERIZACION, ENZIMAS ADAPTADAS AL FRIO?.

    OpenAIRE

    BARRIGA GONZALEZ, ANDRES ANTONIO; BARRIGA GONZALEZ, ANDRES ANTONIO

    2006-01-01

    La temperatura es uno de los factores ambientales más importantes para la vida, siendo los ambientes fríos los que presentan la mayor distribución en la biosfera. Diferentes organismos han desarrollado diversas estrategias de tolerancia y adaptación al fr 160p.

  6. Radiation Resistance of Enzymes in Foods Irradiated Against Microbial Damage; Radioresistance des Enzymes dans les Denrees Alimentaires Irradiees pour les Proteger Contre les Alterations Dues a des Bacteries; Radiatsionnaya ustojchivost' ehnzimov v pishchevykh produktakh,obluchennykh protiv vrednogo vozdejstviya mikrobov; Radiorresistencia de las Enzimas en los Alimentos Irradiados

    Energy Technology Data Exchange (ETDEWEB)

    Vas, K. [Joint FAO/IAEA Division of Atomic Energy in Agriculture, International Atomic Energy Agency, Vienna (Austria)

    1966-11-15

    , on sait que les substances radiomoueificatrices exercent une influence determinante sur la radioinactivation des enzymes, l'auteur estime qu'il faudrait entreprendre des etudes plus poussees sur les radioprotecteurs et les radiosensibilisateurs avec des enzymes fortement purifies. La grande radiosensibilite qui caracterise ordinairement les enzymes tres purs et, par contraste, l'extreme resistance des enzymes dans les tissus et dans leurs extraits non purifies, demontrent la necessite de determiner les raisons de cette difference, ce qui facilitera sans doute la mise au point d'une methode, rationnelle permettant de controler l'activite des enzymes dans le cadre de l'irradiation des aliments. De cette maniere, on pourrait peut-etre mettre au point une 'methode mixte' inedite, laquelle viendrait s'ajouter aux methodes combinees qui ont deja ete elaborees pour le controle de l'action des enzymes; en d'autres termes, on combinerait l'irradiation avec a) le traitement thermique, b) la refrigeration et c) les methodes physiologiques (par exemple, controle de la giycogenolyse). Le memoire fait brievement le point des applications de ces divers procedes. (author) [Spanish] La mayor parte de las enzimas que actuan durante el almacenamiento, la elaboracion y la conservacion de los alimentos son bastante resistentes a las radiaciones ionizantes. Por lo general, esa resistencia en su propio medio suele ser superior en un orden de magnitud a la de los microorganismos que causan la descomposicion o la alteracion de los alimentos. Debido a ello, dosis de irradiacion suficientes para la estabilizacion microbiologica y cuya aplicacion se considera actualmente apenas economica, no impiden la deterioracion causada por las enzimas. Se ha intentado ya muchas veces inactivar por irradiacion las enzimas de los alimentos, pero a juzgar por el escaso exito de la mayor parte de los ensayos efectuados, es necesario estudiar mucho mas a fondo los aspectos generales de la cuestion a fin de

  7. Ethylene evolution and endo-beta-mannanase activity during lettuce seed germination at high temperature Evolução de etileno e atividade da enzima endo-beta-mananase durante a germinação de sementes de alface sob altas temperaturas

    Directory of Open Access Journals (Sweden)

    Warley Marcos Nascimento

    2004-04-01

    Full Text Available High temperatures during lettuce seed imbibition can delay or completely inhibit germination and the endosperm layer appears to restrict the radicle protrusion. The role of endo-beta-mannanase during lettuce seed germination at 35°C and the influence of ethylene in endo-beta-mannanase regulation were investigated. Seeds of 'Dark Green Boston' (DGB and 'Everglades' (EVE were germinated in water, or 10 mmol L-1 of 1-aminocyclopropane-1-carboxylic acid (ACC, or 10 mmol L-1 of aminoethoxyvinylglycine (AVG, or 20 mmol L-1 of silver thiosulphate (STS. Seeds were also primed in polyethylene glycol (PEG, or PEG + ACC, PEG + AVG, or PEG + STS. Untreated seeds germinated 100% at 20°C. At 35°C, EVE seeds germinated 100%, whereas DGB seeds germinated only 33%. Seed priming or adding ACC during incubation increased germination at 35°C. Higher ethylene evolution was detected in EVE than in DGB during germination at 35°C. AVG did not inhibit seed germination of DGB at 35°C, but STS did. Higher endo-beta-mannanase activity was observed in EVE compared with DGB seeds. Providing ACC either during priming or during germination increased endo-beta-mannanase activity, whereas AVG and STS led to decreased or no activity. Ethylene may overcome the inhibitory effect of high temperature in thermosensitive lettuce seeds due to increased endo-beta-mannanase, possibly leading to weakening of the endosperm.Altas temperaturas durante a embebição das sementes de alface podem atrasar ou inibir a germinação e o endosperma parece ser o responsável na restrição da protrusão da radícula. O envolvimento da enzima endo-beta-mananase durante a germinação de sementes de alface a 35°C e a influência do etileno na regulagem desta enzima foram estudados. Sementes das cultivares Dark Green Boston (DGB e Everglades (EVE foram germinadas em água ou em soluções de 10 mmol L-1 de 1-aminociclopropano-1-ácido carboxilico (ACC, 10 mmol L-1 de amino-etoxi-vinil-glicina (AVG

  8. Ambient pH-regulated enzime secretion in endophytic and pathogenic isolates of the fungal genus Colletotrichum Secreção de enzimas mediada pelo pH do ambiente em isolados patogênicos e endofíticos do fungo Colletotrichum

    Directory of Open Access Journals (Sweden)

    Walter Maccheroni Jr.

    2004-06-01

    Full Text Available In fungi a genetic system ensures that enzymes are secreted mainly at ambient pH values corresponding to their optima of activity. Although a great deal of information has been obtained concerning this environmental response, there is a lack of studies involving phytopathogenic, endophytic and entomopathogenic fungi as well as different aspects of fungus-host interactions. This study compares in a plate-clearing assays, the effect of ambient pH in the secretion of amylase, cellulase, lipase, pectinase and protease by endophytic, phytopathogenic, and entomopathogenic isolates belonging to several species of Colletotrichum. All enzymes were secreted in a pH-dependent manner by all isolates. Endophytes and pathogens showed distinct patterns of protease secretion, with optima at alkaline and acid growth conditions, respectively. In liquid medium, a Pi-repressible acid phosphatase of an endophytic isolate responded to ambient pH, having a 14-fold increase in secreted specific activity at acid pH, as compared to alkaline pH. Furthermore, part of a Colletotrichum pacC homologue gene, coding for a transcriptional factor responsible for pH-regulated gene expression, was cloned. Ambient pH seems to be a general factor controlling enzyme secretion in fungus-host interactions through a conserved genetic circuit.Em fungos, um sistema de regulação gênica garante que enzimas sejam secretadas predominantemente em valores de pH do ambiente próximos aos pH ótimos de atividade correspondentes. Embora muita informação tenha sido acumulada sobre essa resposta adaptativa, não existem estudos envolvendo fungos fitopatogênicos, endofíticos e entomopatogênicos, bem como sobre outros aspectos relacionados às interações fungo-hospedeiro. No presente trabalho foi comparado, em meio sólido, o efeito do pH do ambiente na secreção das enzimas amilase, celulase, lipase, pectinase e protease por isolados endofíticos, fitopatogênico e entomopatog

  9. Avaliação da atividade das enzimas pectina metilesterase e β-Galactosidase em mamões cv. Golden armazenados sob diferentes concentrações de oxigênio Activity of pectin methylesterase and β-Galactosidase enzymes in 'Golden' papaya stored under different oxygen concentrations

    Directory of Open Access Journals (Sweden)

    Luciana Konda de Azevedo Pinto

    2013-03-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar o efeito de atmosferas controladas contendo diferentes concentrações de oxigênio sobre a atividade das enzimas β-galactosidase e pectina metilesterase, e sobre a cor da casca e a firmeza da polpa de mamões 'Golden'. Os frutos foram mantidos por 36 dias, nas seguintes atmosferas controladas: 1% de O2 e 0,03% CO2 com adsorvedor de etileno, 3% de O2 e 0,03% de CO2 com adsorvedor de etileno, 5% O2 e 0,03% de CO2 com adsorvedor de etileno e atmosfera ambiente sem adsorvedor de etileno. A UR e a temperatura foram mantidas entre 85-95% e a 13º C, respectivamente. Os frutos estocados sob atmosfera de 1% de O2 e 0,03% CO2 apresentaram retardamento nas atividades das enzimas β-galactosidase e pectina metilesterase comparado com os frutos estocados nas outras atmosferas avaliadas. Os frutos armazenados sob atmosfera de 1% de O2 e 0,03% O2 também apresentaram atraso no desenvolvimento da cor da casca e amolecimento da polpa.This study was carried out with the objective to evaluate the effect of controlled atmospheres containing different concentration of oxygen on the activity of β-galactosidase and pectinmethylesterase enzymes, on the skin color and pulp firmness in 'Golden' papaya. The fruits were kept for 36 days under the following controlled atmospheres: 1% of O2 and 0.03% CO2 with ethylene absorber, 3% of O2 and 0.03% of CO2 with ethylene absorber, 5% O2 and 0.03% of CO2 with ethylene absorber and environmental atmosphere without ethylene absorber. Relative humidity was set at the range 85-95% and temperature maintained at 13ºC. Fruit stored under atmospheres of 1% of O2 and 0.03% CO2 had a β-galactosidase and pectimethylesterase activities delayed compared with the fruits storage under the other atmospheres evaluated. There was also, a delay in the development of color and pulp softening in fruits stored under atmospheres of 1% of O2 and 0.03% O2.

  10. Efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes em frangos de corte de 1 a 21 dias de idade Effect of pelleting and addition of enzymes and vitamins on the performance and advantage of energy and nutrients in broiler chickens from 1 to 21 days old

    Directory of Open Access Journals (Sweden)

    José Laureano Barbosa Leite

    2008-08-01

    Full Text Available Conduziu-se este experimento para avaliar o efeito da peletização e adição de enzimas e vitaminas sobre o desempenho e aproveitamento da energia e nutrientes, em frangos de corte de 1 a 21 dias de idade. Foram utilizados 350 pintos de corte, COBB, machos, com peso inicial médio de 47g ± 2,5g, em um delineamento inteiramente casualizado, com os tratamentos em arranjos fatorial 3 x 2 (três dietas, com e sem enzimas sendo que as dietas consistiram de uma ração farelada e duas rações peletizadas,uma com adição de vitaminas e minerais após a peletização e a outra com adição de vitaminas e minerais antes da peletização. O tempo e a temperatura da peletizadora variaram de 05 a 09 minutos e 58ºC a 62ºC, respectivamente. Após esse processo, as rações peletizadas foram trituradas, buscando-se manter a mesma granulometria das rações fareladas. O ensaio de desempenho foi realizado com 10 repetições e o de metabolismo com 5 repetições cada tratamento, em uma densidade de 5 aves por parcela (gaiola. As rações foram formuladas com 95% das recomendações nutricionais e fornecidas às aves com uma restrição alimentar de, aproximadamente, 10% do consumo ad libitum, o qual foi calculado diariamente a partir do consumo médio de um grupo de aves controle, que foram submetidas ao consumo à vontade de uma ração formulada para atender 100% dos níveis nutricionais recomendados. O complexo enzimático utilizado foi o Allzyme Vegpro®, contendo em sua composição as enzimas protease, amilase e celulase, adicionado aos tratamentos seguindo as recomendações do fabricante, de 0,5 kg por tonelada de ração. Aos 21 dias de idade avaliou-se o ganho de peso e a conversão alimentar. Também foram coletadas as excretas, pela metodologia de coleta total de excretas, nos dias 20, 21 e 22, para determinação dos valores energéticos das rações e digestibilidade da gordura e da proteína. Pelos resultados obtidos, observou-se que o

  11. Cold induced changes on sugar contents and respiratory enzyme activities in coffee genotypes Alterações dos teores de açúcares e da atividade de enzimas do metabolismo respiratório em genótipos de café submetidos ao frio

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    Fábio Luiz Partelli

    2010-04-01

    Full Text Available The present research aimed to characterize some biochemical responses of Coffea canephora (clones 02 and 153 and C. arabica (Catucaí IPR 102 genotypes subjected to low positive temperatures, helping to elucidate the mechanisms involved in cold tolerance. For that, one year old plants were subjected successively to 1 a temperature decrease (0.5°C a day from 25/20°C to 13/8°C (acclimation period, 2 a three day chilling cycle (3x13/4°C and to 3 a recovery period of 14 days (25/20°C. In Catucaí (less cold sensitive when compared to clone 02 there was an increased activity in the respiratory enzymes malate dehydrogenase and pyruvate kinase. Furthermore, Catucaí showed significant increases along the cold imposition and the higher absolute values after chilling exposure of the soluble sugars (sucrose, glucose, fructose, raffinose, arabinose and mannitol that are frequently involved in osmoregulation and membrane stabilization/protection. The analysis of respiratory enzymes and of soluble sugar balance may give valuable information about the cold acclimation/tolerance mechanisms, contributing to a correct selection and breeding of Coffea sp. genotypes.A pesquisa teve por objetivo caracterizar respostas bioquímicas de genótipos de Coffea canephora (clones 02 and 153 e C. arabica (Catucaí IPR 102 submetidos a baixas temperaturas positivas, ajudando a elucidar os mecanismos envolvidos na tolerância ao frio. Plantas com um ano de idade foram submetidas sucessivamente a 1 decréscimo da temperatura (0,5°C por dia desde 25/20°C até 13/8°C (período de aclimatização, 2 um ciclo de três dias a 13/4°C e 3 14 dias de recuperação (25/20°C. Em Catucaí, genótipo menos sensível ao frio quando comparado com o clone 02, observou-se um aumento das atividades das enzimas malato desidrogenase e piruvate cinase, relacionadas com a respiração. Nesse genótipo, os níveis de açúcares solúveis sacarose, glucose, frutose, rafinose, arabinose e

  12. Avaliação de métodos para manutenção e preservação de bactéria esporulada produtora da enzima CGTase = Evaluation of methods for maintenance and preservation of sporulating bacteria producer of CGTase enzyme

    Directory of Open Access Journals (Sweden)

    Cristiane Moriwaki

    2009-04-01

    Full Text Available A conservação de células sem mudanças morfológicas, fisiológicas ou genéticas é uma necessidade da biotecnologia. Bacillus firmus cepa 37 é uma bactéria esporulada produtora da enzima ciclodextrina glicosiltransferase (CGTase, que transforma o amido em ciclodextrinas (CDs. O objetivo deste estudo foi avaliar a manutenção e preservação de B. firmus cepa 37 estocada em meio de cultivo sólido, solo estéril e em glicerol a baixa temperatura (-70ºC. Para avaliação do melhor método de manutenção da bactéria foram utilizados procedimentos de imobilização das células em matrizes inorgânicas. As células imobilizadas foram submetidas ao teste do efeito da biomassa inicial e à microscopia eletrônica de varredura (MEV. O repique não foi um método adequado, pois a cepadiminuiu a produção de CGTase. A estocagem em solo estéril mostrou-se eficaz e a produção da enzima mantida constante. A conservação a baixas temperaturas também foi satisfatória, com contagem de células praticamente a mesma após 360 dias. A imobilização, avaliada por MEV, não mostrou diferença na adsorção das células conservadas pelosdiferentes métodos. O mesmo ocorreu para o teste do efeito da biomassa inicial, que apresentou maior produção de beta-CD quando do uso de 1,5 g de células.The conservation of cells without morphologic, physiologic or genetic changes is a biotechnology necessity. Bacillus firmus strain 37 is a sporulating bacteria that produces the cyclodextrin lycosyltransferase(CGTase enzyme, which transforms starch into cyclodextrins (CDs. This study aimed to evaluate the maintenance and preservation of B. firmus strain 37 stored in a solid medium, sterile soil and in glycerol at low temperature (-70ºC. In order to evaluate the best bacteria maintenance method, cell immobilization procedures were used on inorganic matrices. The immobilized cells were submitted to the initial biomass effect test and scanning electron

  13. Efeitos da farinha de folhas de mandioca sobre a atividade das enzimas AST, ALT, FA e lipídios hepáticos de ratos Wistar Effects of cassava leaves flour on the AST, ALT, ALP enzymes activity and hepatic lipids of Wistar rats

    Directory of Open Access Journals (Sweden)

    Daniela Séfora de Melo

    2008-12-01

    Full Text Available Folhas de mandioca possuem substâncias como ligninas e saponinas que podem apresentar efeito hipolipidêmico. Todavia, um estudo recente relatou aumento no peso do fígado de ratos alimentados com dietas contendo farinha de folhas de mandioca (FFM - Manihot esculenta Crantz cv. Cacao, tornando-se necessário um estudo mais aprofundado dos efeitos desta farinha sobre os parâmetros hepáticos. Para este estudo, um ensaio biológico com 32 ratos machos Wistar foi conduzido por um período de 7 semanas, sendo os tratamentos: dieta controle e dietas contendo 5, 10 e 15% de FFM. As dietas contendo FFM não apresentaram efeitos sobre as atividades das enzimas Aspartato Aminotransferase (AST e Fosfatase Alcalina (FA, mas aumentaram significativamente a atividade da enzima alanina aminotransferase (ALT. O estudo histopatológico revelou vacuolização do citoplasma dos hepatócitos para todos os grupos. No entanto, a freqüência de animais com vacuolização acentuada foi superior nos grupos que receberam dietas com FFM, apresentando também maiores teores de lipídios e colesterol total hepáticos e maior relação peso fígado/peso corporal. Estes resultados indicam que os antinutrientes presentes nas folhas de mandioca, como taninos, cianeto e saponinas, podem ser responsáveis pela redução da função hepática nos animais alimentados com FFM.Cassava leaves contain substances such as lignins and saponins that can present the hypolipidemic effect. However, a recent study has reported an increase in liver weight of rats fed diet containing cassava leaves flour (CLF - Manihot esculenta Crantz cv. Cacao. Thus, a further study of the effect of this flour on the hepatic parameters is necessary. For the development of this study, a biological assay with 32 male Wistar rats was conducted for a period of 7 weeks with the following treatments: control diet and diets containing 5, 10, and 15% of CLF. The diets containing CLF showed no effects on the

  14. Efeito da adição de aminoácidos essenciais à dieta sobre a secreção de enzimas digestivas de jundiá Rhamdia quelen (Siluriformes, Pimelodidae = Effect of dietary essential amino acids addition on digestive enzime secretion in silver catfish Rhamdia quelen (Siluriformes, Pimelodidae

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    Alexandre Bernardini Ungar

    2009-01-01

    Full Text Available Em estudos realizados com variação no teor de proteína na ração para peixes, foi demonstrado o aumento das atividades de protease alcalina, protease ácida, tripsina e quimiotripsina do trato digestório de jundiá (Rhamdia quelen. Esses fatos sugerem que produtos liberados pela digestão na luz desse trato podem influenciar a síntese e a secreção de enzimas digestivas. A secreção destas enzimas pelo pâncreas, em vertebrados, responde à influência neurale humoral. No presente trabalho, foram testadas quatro concentrações (0, 3, 6 e 12% de uma mistura de aminoácidos (treonina, fenilalanina, leucina, valina, arginina e triptofano em iguaisproporções em dietas isocalóricas contendo 3.500 kcal de energia digestível kg-1 de ração, e dietas isoproteicas contendo 20% de proteína, em juvenis de jundiá. Foram utilizados dez animais portratamento, sendo os peixes estocados num sistema fechado com recirculação de água e temperatura controlada. Os peixes submetidos a estes tratamentos apresentaram atividade da protease alcalina na região anterior do intestino, responsiva aos diferentes níveis aminoácidos da alimentação. Todavia, as atividades protease alcalina do fígado e amilase do fígado e intestino anterior não foram detectadas. Estes resultados sugerem que a atividade protease alcalina do intestino anterior seja induzida por aminoácidos liberados na luz do trato digestório. Studies carried out with variation of protein concentration in the fish feed have shown an increase in the activity of alkaline proteases, acid proteases, trypsin and chimotrypsin from the digestive tract of silver catfish (Rhamdia quelen. These facts suggest that products released by digestion in the lumen of this tract can influenced the synthesis and secretion of digestive enzymes. The secretion of these enzymes by the pancreas in vertebrate responses to neural and humoral influences. In the present study, four concentration (0, 3, 6 and 12% of

  15. Alterations of the Antioxidant Enzyme Activities are not General Characteristics of the Colonization Process by Arbuscular Mycorrhizal Fungi Alteraciones de las Actividades de Enzimas Antioxidantes no son Características Generales del Proceso de Colonización por Hongos Micorrízicos Arbusculares

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    Yakelin Rodríguez

    2012-09-01

    antioxidante durante la colonización radical por los hongos micorrízicos arbusculares, se evaluaron las actividades de enzimas antioxidantes claves en raíces de tomate (Solanum lycopersicum L. inoculadas con seis cepas diferentes: dos Glomus mosseae, Glomus cubense, Glomus intraradices, Glomus sp. y A. scrobiculata. Las cepas G. cubense y A. scrobiculata alcanzaron los niveles de infectividad superiores con valores máximos de colonización e intensidad de 29-10,88% y 18-9,20%, respectivamente; las cepas G. mosseae mostraron una infectividad intermedia, ambas con 15% de colonización e intensidades máximas de 7,64-7,06%, respectivamente; mientras que los niveles de infectividad de las cepas Glomus sp. y G. intraradices fueron inferiores con colonización del 13% e intensidades de 5,07 y 5,41, respectivamente. Algunos patrones de actividad de las enzimas peroxidasa, superóxido dismutasa y polifenol oxidasa no resultaron específicos para los niveles y estadios de colonización, temprano o tardío, ni tipo de cepa. No obstante, la única banda de superóxido dismutasa presente en la colonización temprana y el bajo nivel de actividad guayacol-peroxidasa en estadio tardío presente en todos los tratamientos micorrizados indican que estas respuestas antioxidantes son independientes de la cepa y el grado de colonización. En conjunto, los datos sugieren que las alteraciones de las actividades enzimáticas antioxidantes no son características generales del proceso de colonización por los hongos micorrízicos arbusculares, teniendo probablemente el rol clave sobre estas respuestas las características específicas de cada cepa más que la colonización per se.

  16. EVALUACIÓN DEL USO DE ENZIMAS Y FILTRACIÓN POR GRAVEDAD PARA LA CLARIFICACIÓN DE UNA MEZCLA DILUIDA DE PULPA DE FRUTOS DE CACTUS (OPUNTIA BOLDINGHII BRITTON & ROSE, JUGOS DE NARANJA Y TORONJA EVALUATION OF THE USE OF ENZYMES AND GRAVITY FILTRATION FOR CLARIFICATION OF DILUTED MIXTURE OF CACTUS (OPUNTIA BOLDINGHII BRITTON & ROSE FRUITS PULP, ORANGE AND GRAPEFRUIT JUICES

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    Carlos Alberto Padrón Pereira

    2010-06-01

    Full Text Available En Venezuela los frutos de cactus (Opuntia boldinguii son de escasa utilidad comercial. Para su aprovechamiento se evaluó el efecto del uso combinado de enzimas fibrolíticas y filtración por gravedad en la clarificación de una mezcla diluida de pulpa de frutos de cactus, jugos de naranja y toronja. Se compararon los valores de las curvas de flujo de filtrado de las mezclas hidrolizada y sin hidrolizar mediante la prueba t de Welch. La concentración óptima de enzimas fue 0,76% (v/v. La hidrólisis enzimática previa a la pasteurización no afectó el color de la mezcla. Durante los ensayos de pasteurización (62 ± 1 ºC por 30 min hubo grandes cambios de coloración, solo en la mezcla hidrolizada, por degradación de las betalaínas y la adición de ácido ascórbico (0,5% p/v permitió preservar el color. Hubo diferencias altamente significativas entre los valores de las curvas de flujo de filtrado (PIn Venezuela the fruits of cactus (Opuntia boldinguii are of scarce commercial usefulness. For its utilization the effect of combined use of fibrolytic enzymes and gravity filtration for clarification of diluted mixture of cactus fruits pulp, orange and grapefruit juices was evaluated. The values of filtered-flow curves of hydrolyzed and not hydrolyzed mixtures were compared by means of Welch’s t-test. The optimal enzymes concentration was 0.76% (v/v. The prior enzymatic hydrolysis to the pasteurization does not affect the color of the mixture. During the pasteurization assays (62 ± 1 ºC for 30 min there were large changes of coloring, only in the hydrolyzed mixture, by betalains degradation and the addition of ascorbic acid (0.5% w/v permitted to preserve the color. There were highly significant differences between the filtered-flow curves values (P<0.01. The filtered-flow of the hydrolyzed mixture elapsed 110 min (0.159 mL·min-1 was greater to the not hydrolyzed mixture (control flow to the 8 min (0.100 mL·min-1. The juice production

  17. Digestibilidade aparente dos nutrientes e energia de ração suplementada com enzimas digestivas exógenas para juvenis de tambaqui (Colosssoma macropomum Cuvier, 1818 Apparent digestibility of nutrients and crude energy in diets with addition of exogenous digestive enzymes in tambaqui juveniles ( Colosssoma macropomum Cuvier, 1818

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    Jorge Antonio Moreira da Silva

    2007-01-01

    Full Text Available O experimento foi conduzido com o objetivo de avaliar o efeito da adição de um compelxo multienzimático exógeno composto de amilase, protease, lipase e celulase, em rações de juvenis de tambaqui, sobre os coeficientes de digestibilidade aparente (CDa da proteína bruta (PB, extrato etéreo (EE, carboidratos (ENN e energia bruta (EB. O delineamento experimental foi inteiramente casualizado com quatro tratamentos (quatro níveis de inclusão de enzimas, 0,0; 0,05; 0,10; e 0,15 %, três repetições (no tempo e 10 peixes por unidade experimental. Foram utilizados 40 juvenis de tambaqui, com peso médio de 155,0 ± 0,49 g, distribuídos em quatro tanques de alimentação de 500 l, recebendo refeições à vontade das 8 às 12h, a cada hora. Em seguida os animais foram transferidos para coletores de fezes (200 l, onde permaneceram até às 18h, sendo a coleta de dejetos realizada a cada hora. A determinação dos CDa foi realizada pelo método indireto, sendo utilizado como indicador externo 0,5% de óxido de cromo-III (Cr2O3 incorporado à ração. Os resultados demonstraram que a suplementação das dietas com enzimas exógenas para juvenis de tambaqui aumenta a digestibilidade aparente dos nutrientes e energia bruta, no nível de inclusão de 0,05% (PThe experiment evaluated the effect of dietary supplementation a multienzyme complex containing amylase, protease, lipase and cellulase for tambaqui juveniles on the apparent digestibility coefficients (ADCs of crude protein (CP, ether extract (EE, carbohydrates (CHO and crude energy (CE. A completely randomized experimental design was used with four treatments (level of enzymes 0.0; 0.05; 0.10; and 0.15 % and three replicates (over time, with ten fish per experimental unity. Forty fish weighting 155.0 ± 0.49g were distributed in four 500 l feeding tanks and were fed hourly, from 8 to 12 AM. After this period, fish were transferred for fecal collection units until 6 PM, where feces were

  18. Influence of supplying bullfrog tadpoles with feed containing 28% crude protein on performance and enzymatic activities Influência do fornecimento de uma ração comercial com 28% de proteína bruta sobre o desempenho e a atividade de enzimas digestivas de girinos de rã-touro

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    José Teixeira de Seixas Filho

    2010-01-01

    Full Text Available The objective of this study was evaluate the influence of feeding bullfrog tadpoles on commercial feed containing 28% crude protein (CP, on their digestive enzyme performance and activities. The experiment lasted 60 days, at the density of one tadpole/L in boxes containing 30 L water. A hundred and twenty tadpoles at the 25 Gosner stage averaging weight and length was 0.046 g and 6.22 mm, respectively, were used. Survival rate, length, final weight, weight gain, feed consumption, apparent food conversion, specific growth rate and activities of chime, amylase, lipase and trypisin were the parameters evaluated, biweekly, in five biometries. Quadratic effect was observed for the length and the weight. There was larger growth of the tadpoles from the 15th to the 45th day (19.82 mm. On the 15th day, the tadpoles presented the largest specific growth rate (16.93%/day, and the largest weight gain (5.460 g, feed intake (14.099 g and the best apparent food conversion (2.46 was from the 45th to the 60th day. The specific activity of amylase was 205 times greater at 60 days when compared to the beginning of the experiment. The results demonstrated that, for the three enzymes studied, the action capacity over the tadpole chime increased significantly after the 30th experimental day. Moreover, they suggested a greater capacity of tadpoles to digest carbohydrates in detriment to proteins, and this fact was accentuated in the initial phase of the exogenous feeding of this amphibian. The commercial feed with 28% CP provide good performance in the bullfrog tadpoles, indicating the juvenile formation within commercial bullfrog farming standards.Objetivou-se com este trabalho avaliar a influência da alimentação de girinos de rã-touro com ração comercial contendo 28% de proteína bruta (PB no desempenho e nas atividades de enzimas digestivas desses animais. Utilizaram-se 120 girinos no estágio 25 de Gosner com 0,046 g e 6,22 mm, respectivamente, mantidos em

  19. Filamentous fungi and agro-industrial residues selection for enzyme production of biotechnological interestSeleção de fungos filamentosos e de resíduos agroindustriais para a produção de enzimas de interesse biotecnológico

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    Erivelton César Stroparo

    2012-12-01

    Full Text Available Many fungal enzymes have relevant applications in different industrial areas. The objective of this work was to select fungi producing hydrolytic enzymes, as well as establish agro-industrial wastes capable of inducing higher production levels. Xylanase, endoglucanase, amylase and poligalacturonase activities were determined by incubating the culture filtrates with their respective substrates. Subsequently, the reducing sugars determination was carried out using 3,5-dinitrosalicylic acid reagent.The protein determination was performed according the modified Bradford method. Among the fungal strains evaluated, Aspergillus niger J4 showed higher levels of xylanase production (8.73 ± 0.34 U/ml and this was greatest when brewer’s spent grain was used as substrate (9.80 ± 0.02 U/ml. Penicillium miczynskii produced the highest levels of endoglucanasic activity (0.13 ± 0.03 U/ml, which, in turn, was favored in the pineapple peel presence (0.18 ± 0.02 U/ml. In relation to amylase, A. niger J26 was selected as the best producer strain (6.10 ± 0.30 U/ml with wheat bran as the best substrate for their production (7.32 ± 0.14 U/ml. Penicillium verruculosum exhibited the highest level of poligalacturonase activity (8.65 ± 0.12 U/ml, especially when grown in orange peel presence (10.32 ± 0.10 U/ml. These wastes use in these enzymes production may not only reduce their production cost, but also substantially reduce the environmental impact caused by the deposition of these wastes on the environment.Muitas enzimas produzidas por fungos têm relevantes aplicações em diferentes áreas industriais. O objetivo deste trabalho foi selecionar fungos filamentosos produtores de enzimas hidrolíticas, bem como estabelecer os resíduos agroindustriais capazes de induzir maiores níveis de produção. As atividades xilanásica, endoglucanásica, amilásica e poligalacturonásica foram determinadas incubandose os filtrados de cultura com seus respectivos

  20. Efeito da adição de enzimas em dietas de frangos de corte à base de milho e farelo de soja sobre a digestibilidade ileal de nutrientes Effect of enzymes supplementation in corn soybean meal broiler diets on ileal digestibility of nutrients

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    Anel Atencio Tejedor

    2001-06-01

    Full Text Available Dois experimentos, utilizando pintos de corte Avian Farm, no período de 8 a 18 dias de idade, foram realizados para se avaliar o efeito de enzimas microbianas sobre os coeficientes de digestibilidade (CD ileal aparente da matéria seca (MS, da proteína bruta (PB, da energia bruta (EB, do fósforo (P e do cálcio (Ca de dietas à base de milho e farelo de soja com diferentes níveis de Ca e P disponível (Pd. Óxido crômico (0,5% foi adicionado às dietas a fim de se estimar o fator de indigestibilidade. Todas as aves foram abatidas aos 19 dias, para a coleta da digesta. O primeiro experimento foi realizado em arranjo fatorial 2 x 2, com seis repetições contendo 10 aves. As dietas foram formuladas contendo dois níveis de Ca e Pd normal (1%Ca/0,45%Pd e baixo (0,70%Ca/0,32%Pd x dois níveis de enzima fitase (0 e 1 kg/t de ração. O segundo experimento foi realizado em arranjo fatorial 2 x 3, sendo dois níveis de Ca e Pd normal (1%Ca/0,45%Pd e baixo (0,70%Ca/0,32Pd% e três combinações de enzimas: complexo multienzimático (CM com fitase (Fit: 0 kg/t para o controle, 2 kg/t (CM e 2 kg/t mais 1 kg/t de fitase (CM+Fit, com seis repetições, contendo 10 aves cada. No experimento 1, a adição de fitase melhorou a digestibilidade ileal da MS (5,2%, PB (2,4% e EB (3,8%. Interação significativa foi observada na digestibilidade do Ca e P, sendo que adição da fitase melhorou a digestibilidade do Ca e P em ambos níveis de Ca e P. No segundo experimento, a adição do CM melhorou o CD da PB, P e Ca em 3; 4,7; e 7,8%, respectivamente. A associação do CM+fitase mostrou efeito aditivo no aproveitamento do Ca e P. Interação foi observada para o CD da EB, a adição do CM melhorou a digestibilidade em ambos níveis de Ca e Pd, entretanto o CM+fitase melhorou o CD da EB apenas no nível baixo de Ca e P.Two experiments, using 8 to 18 days old Avian -Farm male broiler chicks, were conducted to evaluate the effect of microbial enzymes on the ileal

  1. Avaliação técnica e econômica da matriz nutricional da enzima fitase em rações contendo farelo de girassol para poedeiras comerciais Technical and economical evaluation of the nutritional matrix of phytase enzyme diets with sunflower meal for laying hens

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    Otto Mack Junqueira

    2010-10-01

    Full Text Available Cento e oitenta poedeiras comerciais Isa Brown, com 60 semanas de idade, foram distribuídas em delineamento inteiramente ao acaso, em esquema fatorial 2 õ 2, com dois níveis de fitase (0 e 500 ftu/kg de ração e dois de farelo de girassol (4 e 8%, totalizando cinco dietas, avaliadas com seis repetições de seis aves. As dietas foram formuladas a partir de uma ração controle, à base de milho e farelo de soja, isenta de fitase e farelo de girassol, valorizando na formulação das dietas a matriz nutricional da fitase. O período experimental foi dividido em quatro ciclos de 28 dias cada. A matriz nutricional preconizada para fitase permitiu o atendimento pleno das exigências das aves, mesmo quando as dietas foram formuladas com níveis nutricionais reduzidos, isso quando desconsiderados os nutrientes presentes na matriz nutricional da enzima, de acordo com recomendação da empresa produtora. A adição de fitase na dieta reduz a excreção de fósforo pelas aves e melhora os parâmetros econômicos. A inclusão de farelo de girassol no nível de 8% prejudica a produção de ovos, mas não afeta os demais parâmetros de desempenho e qualidade dos ovos.One hundred and eighty Isa Brown laying hens at 60 weeks of age were arranged in a completely randomized design in a 2 õ 2 factorial scheme, with two levels of phytase (0 and 500 ftu/kg ration and two levels of sunflower meal (4 and 8% totalizing five diets, evaluated with six replicates with six birds. Diets were formulated from a control ration based on corn and soybean meal free from phytase and sunflower meal, valuing the nutritional phytase matrix in diets formulation. The experimental period was divided in four 28-day cycles. The nutritional matrix suggested for phytase completely met the requirement by hens, even when diets were formulated with reduced nutritional levels when the nutrients present in the enzyme nutritional matrix were not considered accordingly to recommendations by

  2. Uso del escobajo como sustrato para el crecimiento de hongos de la pudrición blanca, la producción de enzimas ligninolíticas y la decoloración de tinturas Grape stalks as substrate for white rot fungi, lignocellulolytic enzyme production and dye decolorization

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    Laura Levin

    2012-06-01

    Full Text Available El objetivo de este trabajo fue evaluar el potencial del escobajo, un residuo agroindustrial, como sustrato para el crecimiento y la producción de enzimas lignocelulósicas de tres hongos causantes de pudrición blanca en la madera: Trametes trogii, Stereum hirsutum y Coriolus antarcticus. Para ello se utilizaron técnicas de fermentación en estado sólido. También se ensayó la decoloración de colorantes industriales sobre estos cultivos. La pérdida de peso seco del sustrato fue similar después del día 60 (33-43 %. C. antarcticus produjo las mayores actividades de lacasa y Mn-peroxidasa (33,0 y 1,6 U/g peso seco. La mayor actividad endoglucanasa fue medida en cultivos de S. hirsutum (10,4 U/g, y la mayor actividad endoxilanasa en T. trogii (14,6 U/g. El sistema C. antarcticus/escobap mostró un importante potencial para su aplicación en la biorremediación de efluentes textiles, con porcentajes de decoloración de 93, 86, 82, 82, 77 y 58 % para índigo carmín, verde de malaquita, azure B, azul R brillante de remazol, cristal violeta y xilidina, respectivamente, en 5 h.The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %. C. antarcticus produced the highest laccase and Mn-peroxldase activities (33.0 and 1.6 U/g dry solid. The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g, while the endoxylanase peak corresponded to T. trogii (14.6 U/g. The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82

  3. Screening para el aislamiento y caracterización de microorganismos y enzimas potencialmente útiles para la degradación de celulosas y hemicelulosas Screening for isolation and characterisation of microorganisms and enzymes with usefull potential for degradation of celullose and hemicelluose

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    Mikán Venegas José Fernando

    2004-07-01

    Full Text Available Se presenta un modelo práctico de microbiología aplicada y biotecnología para aislar y caracterizar microorganismos, como una minús­cula muestra de la extensa biodiversidad de nuestros suelos. Se analiza su capacidad para producir depolimerasas e hidrolasas accesorias para la degradación de xiloglucanos-pectatos o glucoarabinoxilanos, con el fin de evaluar su potencial como degradadores de material vegetal. Se propone el uso del cultivo en paredes celulares vegetales como única fuente de carbono, como inductores de las actividades hidrolíticas, y el uso de las mismas paredes celulares y de xilano entrecruzado para purificar en forma rápida y económica enzimas degradadoras de celulosas y hemicelulosas. Con estos soportes de afinidad se logró un redimiento de purificación de xilanasas del 500% en un solo paso. Partiendo de 65 aislamientos se seleccionaron cinco, a los cuales se les hizo caracterización isoenzimática para celulasas y xilanasas. Se les sugiere como potencialmente útiles en compostaje y otros procesos industriales. Palabras clave: celulasas, hemicelulasas, cromatografía de afinidad, sustratos entrecruzados, diversidad microbiológica, compostaje.A practical, applied microbiology and biotechnology model is presented for isolating and characterising micro-organisms, this being a tiny part of the immense biodiversity of tropical soils. These microbes' ability to produce depolymerases and accessory hydrolases degrading xyloglucans-pectates or glucoarabinoxylans is analysed to evaluate their potential for degrading plant material. We propose culturing micro-organisms on the cell wall as main carbon source and as hydrolitic activity inducer. The same cell walls can be used for cross-linking xylan and for rapid, low cost purification of cellulose and hemicellose degrading enzymes. A 500% xylanase purification yield was obtained in a single step with these affinity supports. Out of the 65 isolates obtained were finally

  4. Evaluación preliminar del efecto que sobre algunas enzimas del suelo tienen diferentes mecanismos de control del hongo (Phytophthora infestans en un cultivo de papa (Solanum tuberosum bajo dos tipos de manejo agrícola (orgánico y convencional

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    Pedro Nel Murcia García

    2004-07-01

    Full Text Available Se evaluó comparativamente el posible efecto diferencial que, sobre la actividad de las enzimas proteasa, fosfatasa ácida, fosfatasa alcalina y celulasa, además del pH y la materia orgánica del suelo, tuvieron los métodos de control de Phytophthora infestans tanto en la agricultura orgánica (purín de Chipaca Bidens pilosum como en la convencional (diversos fungicidas comerciales en plantas de papa (Solanum tuberosum. Igualmente, en los parámetros antes mencionados, se evaluó el efecto de un promotor fúngico utilizado como control del mismo hongo en ambas agriculturas. La investigación se dividió en una fase de campo y una de laboratorio. En la fase de campo, realizada durante siete meses de 1999, se acompañó la siembra, el desarrollo del cultivo y evolución de la enfermedad a través de la determinación de la incidencia y su severidad. En el laboratorio se determinó la actividad enzimática proteasa, fosfatasa ácida, fosfatasa alcalina, celulasa, así como también el pH y porcentaje de materia orgánica. Se encontró que en el manejo agrícola orgánico la actividad de la fosfatasa ácida, la fosfatasa alcalina y la proteasa así como también el pH fueron más influenciados por el estado de desarrollo de las plantas que por efecto del los tratamientos utilizados en el control del hongo. En el manejo agrícola convencional la actividad enzimática de las celulasas fue inhibida significativamente por los fungicidas. La actividad de las proteasas y fosfatasas ácidas fueron estimuladas por efecto de los fungicidas comerciales y por el estado de desarrollo de las plantas. Las actividades enzimáticas fosfatasa ácida, proteasa y celulasa presentaron comportamientos significativamente diferentes entre los cultivos convencional y orgánico. Para el control de la enfermedad, el uso de los fungicidas fue el tratamiento que mejores resultados presentó con una mayor producción de papa pero con mayores gastos de producción, mientras

  5. Comparative Assay of Glutathione S- Transferase (GSTs Activity of Excretory-Secretory Materials and Somatic Extract of Fasciola spp Parasites

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    Heshmatollah Alirahmi

    2010-12-01

    Full Text Available Fascioliasis is a worldwide parasitic disease in human and domestic animals. The causative agents of fascioliasis are Fasciola hepatica and Fasciola gigantica. In the recent years, fasciola resistance to drugs has been reported in the many of publications. Fasciola spp has detoxification system including GST enzyme which may be responsible for its resistance. Therefore , the aim of the study was to assay of GST enzyme activity in fasciola parasites. Fasciola gigantica and Fasciola hepatica helminths were collected from abattoir as a live and cultured in buffer media for 4 h at 37 °C. Excretory-Secretory products were collected and stored in -80◦C. F. gigantica and Fasciola hepatica were homogenized with homogenizing buffer in a glass homogenizer to prepare of somatic extract. Suspension was then centrifuged and supernatant was stored at -80°C. In order to assay the enzyme activity, excretory-secretory and somatic extracts in the form of cocktails (potassium phosphate buffer, reduced glutathione and 1-chloro-2,4-dinitrobenzene substrates were prepared and their absorbance recorded for 5 minutes at 340 nm. The total and specific GST activity of F. gigantica somatic and ES products were obtained as 2916.00, 272.01 micromole/minute and 1.33, 1.70 micromole/minute/mg protein, respectively. Fasciola hepatica also showed 2705.00, 276.86 micromole/minute and 1.33, 1.52 micromole/minute/mg protein, respectively. These results are important for analysis of parasite survival / resistance to drugs which use for treatment of fascioliasis.

  6. Comparative Assay of Glutathione S- Transferase (GSTs Activity of Excretory-Secretory Materials and Somatic Extract of Fasciola spp Parasites

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    Taghi Golmohamadi

    2010-11-01

    Full Text Available Fascioliasis is a worldwide parasitic disease in human and domestic animals. The causative agents of fascioliasis are Fasciola hepatica and Fasciola gigantica. In the recent years, fasciola resistance to drugs has been reported in the many of publications. Fasciola spp has detoxification system including GST enzyme which may be responsible for its resistance. Therefore , the aim of the study was to assay of GST enzyme activity in fasciola parasites. Fasciola gigantica and Fasciola hepatica helminths were collected from abattoir as a live and cultured in buffer media for 4 h at 37 °C. Excretory-Secretory products were collected and stored in -80◦C. F. gigantica and Fasciola hepatica were homogenized with homogenizing buffer in a glass homogenizer to prepare of somatic extract. Suspension was then centrifuged and supernatant was stored at -80°C. In order to assay the enzyme activity, excretory-secretory and somatic extracts in the form of cocktails (potassium phosphate buffer, reduced glutathione and 1-chloro-2,4-dinitrobenzene substrates were prepared and their absorbance recorded for 5 minutes at 340 nm. The total and specific GST activity of F. gigantica somatic and ES products were obtained as 2916.00, 272.01 micromole/minute and 1.33, 1.70 micromole/minute/mg protein, respectively. Fasciola hepatica also showed 2705.00, 276.86 micromole/minute and 1.33, 1.52 micromole/minute/mg protein, respectively. These results are important for analysis of parasite survival / resistance to drugs which use for treatment of fascioliasis.

  7. Influência da adubação potássica na produção e na atividade de enzimas pós-colheita em escarola (Cichorium endivia L. / Influence of potassium fertilization in endive (Cichorium endiviaL. production and enzyme post-harvest activity

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    Paulo Sérgio Pavinato

    2009-12-01

    Full Text Available ResumoO potássio é um dos nutrientes mais abundantes no citoplasma das células vegetais, e sua alta contribuição no metabolismo das plantas está relacionada ao controle osmótico das células e à ativação de inúmeras enzimas. Sendo de conhecimento que a produção e manutenção da qualidade pós-colheita de sementes, frutos e hortaliças depende da boa nutrição potássica, o presente trabalho teve por objetivo avaliar o efeito de doses de potássio na produção e qualidade pós-colheita de escarola. A escarola, variedade Malan, foi cultivada em vasos com capacidade de 10 kg de solo, em casa de vegetação, na Fazenda Experimental Lajeado, Departamento de Produção Vegetal/Horticultura da FCA-UNESP, Botucatu-SP. Os tratamentos consistiram em cinco doses de potássio, correspondentes a 0, 75, 150, 300 e 600 kg ha-1 de K2O, aplicadas 1/3 no plantio e o restante em três coberturas (8, 16 e 28 dias após o transplante. Por ocasião do transplante, aplicou-se a adubação nitrogenada e fosfatada recomendadas para a cultura. Aos 35 dias após o transplante, as plantas foram colhidas e se efetuaram as avaliações de diâmetro de cabeça, massa fresca e área foliar. Ainda utilizando plantas frescas, determinou-se a atividade das enzimas polifenol oxidase e peroxidase. Em plantas secas, em estufa a 60°C por 72 h, foram determinadas a massa seca, o teor de K no tecido e o acúmulo total de proteínas. De maneira geral, a aplicação de 150 kg ha-1 de K2O, correspondente à dose recomendada pelos boletins de adubação para a escarola, resultou em máxima produção e qualidade pós-colheita, não respondendo a doses mais elevadas.AbstractPotassium is one of the nutrients that is present in higher levels in the cytoplasm of plant cells, and its contribution in plant metabolism is related to cell osmotic regulation and the activation of many enzymes. Given the knowledge that production and post-harvest quality maintenance of seeds, fruit

  8. Estonian household forms and motives for saving and borrowing / Marge Sults

    Index Scriptorium Estoniae

    Sults, Marge

    2003-01-01

    Kui 1990-ndate alguses mõjutas majapidamissektori säästmiskäitumist inflatsioon, siis nüüd on oluliseks saanud nii sissetulekute kasv, madalad laenuintressid kui ka uued laenutooted ja väiksemad laenupiirangud. Siia lisandub Eestis läbiviidav pensionireform, mis peaks säästmisele mõjuma positiivselt. Tabelid

  9. Sult er en sjælden årsag til metabolisk acidose

    DEFF Research Database (Denmark)

    Vestergaard, Thea; Aaen, Jeppe Frøkjær; Bruun, Jens Meldgaard

    2014-01-01

    of infection, dehydration and normoglycaemic metabolic acidosis with elevated P-3-hydroxybutyrate. The case presents a starvation- (weight loss ~ 13 kg) and infection-induced non-diabetic metabolic ketoacidosis treated with intravenous supplementation of isotonic saline, potassium, bicarbonate and insulin....

  10. Aplicação de 1-metilciclopropeno em banana 'Prata-Anã' e seu efeito sobre a substâncias pécticas e enzimas pectinolíticas Application of 1-Methylcyclopropene on bananas cv. 'Prata-Anã' and its effect upon pectic substances and pectinolytic enzymes

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    Alenir Naves de Sales

    2004-06-01

    Full Text Available No presente estudo, visou-se a verificar o efeito do 1-metilciclopropeno (1-MCP, um produto bloqueador do etileno, sobre a qualidade da banana 'Prata-Anã'. Os frutos foram colhidos no estádio de maturação 1, que corresponde ao estádio de cor da casca verde e separados em grupos, de acordo com os dois diferentes calibres. Cada parcela foi composta por um buquê de seis dedos, com quatro repetições para cada tratamento. Foram utilizadas 4 concentrações de 1-MCP: 0, 30, 60 e 90 ng.g-1, preparadas a partir do produto comercial (0,14% m/m de de i. a. Os frutos , exceto os do grupo controle, foram armazenados por 20 dias a 12ºC, seguidos de climatização com 1,5% da mistura etil 5 a 17ºC durante 24 horas, após o que foram transferidos para ambiente comum (23°C por 93 horas, antes de serem submetidos às análises químicas e bioquímicas. Frutos tratados com 1-MCP, especialmente na dose de 60 ng.g-1, apresentaram reduzidos teores de pectina solúvel, porcentagens de solubilização de pectinas e menores atividades das enzimas pectinametilesterase (PME e poligalacturonase (PG que os frutos não tratados. O uso do 1-MCP, nas concentrações utilizadas, não impediu que o processo de amadurecimento evoluísse normalmente após a climatização dos frutos.The effects of 1 methylciclopropene (1-MCP, an ethylene blocker compound, on the quality of "Prata-Anã" bananas were investigated. The fruits were harvested in maturation stage 1, corresponding to the green skin color stage and separated into groups according to the two different calibers. Each plot was made up of a bouquet of six fingers with four replicates per each treatment. Four concentrations of 1-MCP (0, 30, 60 and 90 ng.g-1 were tested, with a powder-formulation at the concentration of 0.14% of active ingredient being used. The fruits were stored for a period of 20 days at the temperature of 12°C. After this step, with the exception of the control group, climatization of the

  11. Análise da variabilidade da freqüência cardíaca em pacientes hipertensos, antes e depois do tratamento com inibidores da enzima conversora da angiotensina II Analysis of heart rate variability in hypertensive patients before and after treatment with angiotensin II-converting enzyme inhibitors

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    Antônio da Silva Menezes Júnior

    2004-08-01

    Full Text Available OBJETIVO: Comparar a variabilidade de freqüência cardíaca em indivíduos normotensos e hipertensos e observar o comportamento do sistema nervoso autônomo após terapia com inibidores da enzima conversora de angiotensina II. MÉTODO: Estudados 286 pacientes com diagnóstico de hipertensão arterial, pela 1ª vez, e divididos em 4 grupos, conforme a pressão arterial diastólica (PAD: grupo A - PAD110 mmHg. Os pacientes do grupo A (normais e do grupo C (HA moderada, somando 110 e 79 pacientes, respectivamente, submeteram-se ao Holter-ECG 24h com análise de variabilidade de freqüência cardíaca no domínio do tempo (DT e no domínio da freqüência (DF. O grupo C foi tratado com inibidores da ECA durante 3 meses, e após esse período novamente avaliado com Holter-ECG 24h e variabilidade da freqüência cardíaca, e os valores comparados com os normotensos. RESULTADOS: Os parâmetros SDNN, PNN50 (DT e o espectro LF (DF foram significativamente diferentes para os dois grupos, com valores notadamente diminuídos em hipertensos (pOBJECTIVE: To compare heart rate variability in normotensive and hypertensive individuals and to observe the behavior of the autonomic nervous system after treatment with angiotensin II-converting enzyme inhibitors. METHOD: The study comprised 286 patients diagnosed with arterial hypertension (AH for the first time and divided into 4 groups according to diastolic blood pressure (DBP levels: group A - DBP110 mmHg. Group A (110 healthy individuals and group C (79 patients with moderate AH underwent 24-hour Holter-ECG with analysis of heart rate variability in time domain (TD and frequency domain (FD. The group C patients were treated with ACE inhibitors for 3 months, and, after this period, they underwent a new 24-hour Holter-ECG study for assessing heart rate variability, the values being compared with those of normotensive individuals. RESULTS: The SDNN and PNN50 parameters (TD, and the LF spectrum (FD were

  12. Análisis del consumo de inhibidores de la enzima convertidora de angioténsina en el territorio oeste de La Habana, 2005-2009 Analysis of the consumption of angiotensin-converting enzyme inhibitors in the west side of Havana, 2005-2009

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    José Ramón Cabrera Cepero

    2011-12-01

    Full Text Available La planificación de los recursos es un problema trascendental en los países en desarrollo y también en Cuba, por lo que hacer el mejor uso de los presupuestos limitados y de las escasas divisas, es de vital importancia. Planificar las cantidades de medicamentos necesarias, para lograr garantizar una disponibilidad adecuada de estos en todos los niveles de asistencia, es una tarea en la cual intervienen un sinnúmero de factores. El objetivo de este trabajo fue demostrar en qué medida la introducción del enalapril tabletas influyó en el consumo del captopril tabletas, mediante el análisis de los patrones de consumo de los medicamentos inhibidores de la enzima convertidora de angiotensina en el territorio oeste de La Habana entre marzo de 2005 y diciembre de 2009. Para ello se realizó un estudio de utilización de medicamentos de consumo, de tipo descriptivo, observacional y retrospectivo. Se calcularon las DHD (dosis por mil habitantes día. Los resultados de este trabajo demuestran cómo en este grupo hay un desplazamiento del consumo hacia el enalapril. Este es un comportamiento lógico por la comodidad de la administración y la menor incidencia de efectos adversos. Sin embargo, el captopril se mantiene en valores entre 20 y 30 DHD x 1 000 habitantes ya que hay un grupo de pacientes que continúan con este tratamiento y es de elección en la crisis hipertensiva.The planning of resources is a pressing problem in the developing nations including Cuba, hence using restricted budgets and dwindling foreign currencies in the best possible way is a must. Planning the amount of required drugs to assure their adequate supply at all medical assistance levels is a vital task in which a number of factors are involved. This paper was aimed at showing to what extent the introduction of enalapril pills into the market influenced the consumption of captopril tablets, through the analysis of the consumption patterns of angiotensin-converting enzyme

  13. Ligninolytic enzymes production and Remazol brilliant blue R decolorization by tropical brazilian basidiomycetes fungi Produção de enzimas ligninolíticas e descoloração do corante azul brilhante de Remazol R por fungos basidiomicetos tropicais brasileiros

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    Kátia M. G. Machado

    2005-09-01

    em solo contaminado com organoclorados foi também avaliada. Cento e seis fungos descoloriram o RBBR durante o crescimento em meio sólido (agar extrato malte; noventa e seis desses fungos mostraram crescimento micelial e descoloração superiores a uma cepa de Phanerochaete chrysosporium usada como referência. Trinta e cinco fungos foram crescidos em meio sólido contendo bagaço de cana-de-açúcar (BGS e seus extratos foram avaliados quanto a descoloração do RBBR e a produção de atividade de peroxidases. Todos os fungos mostraram atividade de peroxidases, mas 5 foram incapazes de descolorir o RBBR. Diferentes padrões de enzimas lignolíticas foram detectados em 12 desses extratos fúngicos, porém todos mostraram atividade de laccase. Atividade de peroxidase dependente de manganês (MnP foi produzida por Melanoporia nigra, Peniophora cinerea, Psilocybe castanella, três cepas de Trametes villosa, T. versicolor e Trichaptum byssogenum. Trogia buccinalis apresentou a maior descoloração do RBBR e não produziu MnP. Descoloração do RBBR sem produção de MnP foi também observada para as três cepas de Lentinus testadas. Altos níveis de atividades de peroxidases e laccases não mostraram relação com significativa descoloração do RBBR. Foi observada descoloração do RBBR por extratos obtidos de P. castanella, L. crinitus, P. cinerea e duas cepas de T. Villosa durante crescimento em solos contaminados com pentaclorofenol e hexaclorobenzeno. Estes fungos mostraram maior descoloração de RBBR na presença de compostos organoclorados do que em solos não contaminados.

  14. Proteólisis cerebral del péptido amiloide-ß: Relevancia de la enzima degradadora de insulina en la enfermedad de Alzheimer Cerebral proteolysis of amyloid-ß peptide: Relevance of insulin-degrading enzyme in Alzheimer's disease

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    María Celeste Leal

    2009-10-01

    Full Text Available El aumento global de la expectativa de vida convierte a la enfermedad de Alzheimer (EA en un problema creciente. Una de las características distintivas de EA es la acumulación excesiva del péptido amiloide ß (Aß en el cerebro. En los últimos años se ha fortalecido el concepto de que la degradación de Aß por proteasas in situ es un mecanismo importante que previene su acumulación cerebral. Datos bioquímicos y genéticos mostraron que la enzima degradadora de insulina (IDE participa en la homeostasis de Aß e insulina. La expresión y la actividad de IDE están significativamente disminuidas en cerebros con EA comparados con controles de igual edad. Además, IDE se deposita con Aß en placas seniles y vasos, indicando un grosero cambio conformacional producto de distintos mecanismos post-traduccionales. Estas alteraciones en la distribución y actividad de IDE resultan en una insuficiente degradación de Aß e insulina y promueven la formación de oligómeros de Aß y la resistencia a la hormona, procesos que convergen hacia la neurodegeneración. El estudio de los mecanismos de eliminación de Aß cerebral no sólo ayudará a comprender la patogenia de EA sino que permitirá una mejor interpretación de los ensayos clínicos en curso y el desarrollo de nuevas estrategias terapéuticas.The global increase in life expectancy turns Alzheimer's disease (AD into a growing problem. One of the distinctive features of AD is the excessive accumulation of amyloid-ß (Aß peptide in the brain. In recent years, a concept that has gained strength is that degradation of Aß by proteases in situ is an important mechanism that prevents cerebral peptide accumulation. Biochemical and genetic data have shown that insulin-degrading enzyme (IDE participates in Aß and insulin homeostasis. IDE expression and activity are significantly decreased in AD brains compared to age-matched controls. Also, IDE is deposited with Aß in senile plaques and blood vessels

  15. Desenvolvimento de populações duplo-haplóides de cevada cervejeira associadas à atividade das enzimas (1-3, 1-4-β-glucanases Development of doubled-haploids populations in malting barley associated to activity of enzymes (1-3, 1-4-β-glucanases

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    Janaína Endres Georg-Kraemer

    2011-05-01

    Full Text Available Populações duplo-haplóides apresentam especial vantagem para análises genéticas, uma vez que a informação que elas oferecem pode ser maximizada, devido ao fato que todos os locos encontram-se em homozigose. O objetivo deste trabalho foi o desenvolvimento de duas populações duplo-haplóides (DHs de cevada (Hordeum vulgare ssp. vulgare L. segregantes para a atividade das enzimas (1-3, 1-4-β-glucanases, através da técnica de cultura de anteras. Foram realizados dois cruzamentos com cultivares contrastantes para esta característica. As cultivares parentais selecionadas foram 'MN 698' e 'CEV 97047', para o desenvolvimento da população "malte verde" (MV, e 'Embrapa 127' e 'CEV 96025' para o desenvolvimento da população "malte seco" (MS. Foram cultivadas 10.734 anteras da população MS e 4.139 anteras da população MV. A população MV produziu 50% mais plântulas verdes quando comparada à população MS, refletindo a importância do genótipo na resposta à cultura de anteras e na regeneração. A maioria das plantas adultas duplo-haplóides foi obtida através da duplicação espontânea in vitro do genoma haplóide, ocorrendo em 66% das plantas da população MS e 76% das plantas da população MV. Também foram observadas, em menor frequência, plantas haplóides, triplóides e tetraplóides. Através da técnica de cultura de anteras, foram desenvolvidas 204 linhagens duplo-haplóides, das quais 72 linhagens são da população "malte seco" e 132 linhagens são da população "malte verde". Este material constitui um importante germoplasma para o melhoramento genético da cevada.Doubled haploid populations offer special advantages in genetic analyses, since the information they provide may be maximized due to the fact that all loci are homozygous. The aim of this study was to develop two barley (Hordeum vulgare ssp.vulgare L. doubled-haploid (DHs populations segregating to (1-3, 1-4-β-glucanases activity, utilizing the anther

  16. Development of Radiation-Sterilized Sea Food Products. I. Enzyme-Inactivated Cod and Halibut Patties; Essais de Radiosterilisation des Produits Alimentaires d'Origine Marine. I. Pates de Morue et de Fletan a Enzymes Inactives; Primenenie izlucheniya dlya sterilizatsii morskikh pishchevykh produktov; Preparacion de Alimentos de Origen Marino Esterilizados por Irradiacion. I. Pastelillos de Bacalao y de Hipogloso con Enzimas Inactivadas

    Energy Technology Data Exchange (ETDEWEB)

    Sinnhuber, R. O.; Landers, Mary K.; Yu, T. C. [Department of Food Science And Technology, Oregon State University, Corvallis, OR (United States); Simon, M.; Heiligman, F. [United States Army Natick Laboratories, Natick, MA (United States)

    1966-11-15

    ont ete inactives par Inverted-Exclamation-Mark immersion des saucisses dans un bain d'eau bouillante. Apres refroidissement pour laisser prendre les proteines, les saucisses ont ete debitees en tranches de 1 cm d'epaisseur, puis mises en boites et irradiees a 4,5 Mrad. Le produit radiosterilise a ete emmagasine pendant 12 mois a une temperature de 22 Degree-Sign C; il- a ete procede periodiquement a une evaluation de la qualite et de l'effet des divers traitements. Ces traitements comportaient l'emballage sous vide, l'addition de divers anti-oxydants et l'emploi de paquets de charbon de bois. Pour la consommation, les produits ont ete trempes dans de la pate a frire, roules dans de la chapelure et passes a la friture. Le produit a ete evalue par des groupes de degustateurs; on a egalement fait des mesures objectives sur le total des bases volatiles, l'indice d'acide 2-thiobarbiturique, le pH et le coefficient de reflexion des couleurs. Les groupes de degustateurs (composes de 140 a 170 membres) ont donne des cotes satisfaisantes aux produits pendant 12 mois de stockage a 22 Degree-Sign C. Bien que ces groupes aient prefere les echantillons temoins non irradies aux echantillons irradies, apres 12 mois, tous les pates irradies conserves ont ete classes du cote positif de l'echelle hedonistique des qualites (neuf degres). Le coefficient de reflexion des couleurs des produits alimentaires d'origine marine radiosterilises peut servir a evaluer le brunissement produit par l'action des rayonnements et parait etre en rapport avec la duree de conservation. (author) [Spanish] Se han preparado pastelillos o tortas de bacalao (Gadus macrocephalus) e hipogloso (Hippoglossus stenolepsis) esterilizados por irradiacion, con inactivacion de enzimas, productos que ofrecen interes desde el punto de vista comercial. Se prepararon mezclando el pescado picado con harina de maiz, gelatina y sal y dando a la masa forma de salchicha. Las enzimas se inactivaron calentando las salchichas en un

  17. Avaliação de métodos para manutenção e preservação de bactéria esporulada produtora da enzima CGTase - DOI: 10.4025/actascihealthsci.v31i2.6910 Evaluation of methods for maintenance and preservation of sporulating bacteria producer of CGTase enzyme- DOI: 10.4025/actascihealthsci.v31i2.6910

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    Cristiane Moriwaki

    2009-09-01

    Full Text Available A conservação de células sem mudanças morfológicas, fisiológicas ou genéticas é uma necessidade da biotecnologia. Bacillus firmus cepa 37 é uma bactéria esporulada produtora da enzima ciclodextrina glicosiltransferase (CGTase, que transforma o amido em ciclodextrinas (CDs. O objetivo deste estudo foi avaliar a manutenção e preservação de B. firmus cepa 37 estocada em meio de cultivo sólido, solo estéril e em glicerol a baixa temperatura (-70ºC. Para avaliação do melhor método de manutenção da bactéria foram utilizados procedimentos de imobilização das células em matrizes inorgânicas. As células imobilizadas foram submetidas ao teste do efeito da biomassa inicial e à microscopia eletrônica de varredura (MEV. O repique não foi um método adequado, pois a cepa diminuiu a produção de CGTase. A estocagem em solo estéril mostrou-se eficaz e a produção da enzima mantida constante. A conservação a baixas temperaturas também foi satisfatória, com contagem de células praticamente a mesma após 360 dias. A imobilização, avaliada por MEV, não mostrou diferença na adsorção das células conservadas pelos diferentes métodos. O mesmo ocorreu para o teste do efeito da biomassa inicial, que apresentou maior produção de beta-CD quando do uso de 1,5 g de células.The conservation of cells without morphologic, physiologic or genetic changes is a biotechnology necessity. Bacillus firmus strain 37 is a sporulating bacteria that produces the cyclodextrin glycosyltransferase (CGTase enzyme, which transforms starch into cyclodextrins (CDs. This study aimed to evaluate the maintenance and preservation of B. firmus strain 37 stored in a solid medium, sterile soil and in glycerol at low temperature (-70ºC. In order to evaluate the best bacteria maintenance method, cell immobilization procedures were used on inorganic matrices. The immobilized cells were submitted to the initial biomass effect test and scanning electron

  18. EFFECT OF A VITAMIN E AND SELENIUM ORAL SUPPLEMENTATION ON HEMATOLOGICAL PARAMETERS, MUSCULAR INJURIES MARKERS ENZYMES AND PEROXIDATION INDICES OF BIOMOLECULES IN SHOW JUMPING HORSES EFEITO DA SUPLEMENTAÇÃO COM VITAMINA E E SELÊNIO SOBRE O QUADRO HEMATOLÓGICO, ENZIMAS MARCADORAS DE LESÃO MUSCULAR E ÍNDICE DE PEROXIDAÇÃO DE BIOMOLÉCULAS EM EQUINOS SUBMETIDOS À ATIVIDADE DE SALTO

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    Domingos Cachineiro Rodrigues Dias

    2009-09-01

    , vitamin E.
    As alterações dos constituintes sanguíneos e o estresse oxidativo são mecanismos fisiopatológicos incriminados no aparecimento de lesões relacionadas ao exercício. Avaliou-se a influência da suplementação oral à base de ?-tocoferol (vitamina E e selênio sobre o quadro hematológico, bem como a atividade sérica de enzimas marcadoras de lesão muscular e o nível de substâncias derivadas da ação dos radicais livres sobre biomoléculas presentes na membrana de eritrócitos (TBARS de equinos normalmente treinados e submetidos à prova de hipismo clássico. Para isso, distribuíram-se vinte cavalos em dois grupos, sendo um suplementado com produto à base de vitamina E (2500 mg/dia e selênio (3 mg/dia por 45 dias (GT e outro mantido como controle (GC. Colheram-se amostras de sangue antes (TR e após (T0 a realização do exercício e seis (T6, doze (T12 e 24 horas (T24 após o término da atividade de esforço. Foram avaliados os constituintes do hemograma, a atividade sérica das enzimas CK, AST e LDH e a concentração TBARS na membrana de eritrócitos. A suplementação utilizada apresentou efeito sobre alguns parâmetros do hemograma, uma vez que no GT houve retorno aos níveis basais de número de hemácias e leucócitos, caracterizado por neutrofilia, em até seis horas. No GC, tais valores retornaram aos níveis de repouso entre 12 e 24 horas. Para a AST, o GT retornou ao valor do repouso seis horas após a realização do exercício. No entanto, não houve efeito sobre as enzimas CK e LDH, nem para o TBARS. Apesar de terem sido observadas diferenças na dinâmica de alguns parâmetros hematológicos entre os grupos, não foi possível determinar atividade antioxidante no GT no delineamento experimental utilizado, o que demonstra a necessidade de mais estudos para o entendimento do estresse oxidativo em cavalos atletas e a suplementação com antioxidantes na dieta desses animais.

    PALAVRAS-CHAVES: Cavalo atleta, estresse

  19. O uso de inibidores da enzima conversora de angiotensina e sua relação com eventos no pós-operatório de cirurgia de revascularização miocárdica The use of inhibitors of angiotensin-converting enzyme and its relation to events in the postoperative period of CABG

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    Graciane Radaelli

    2011-09-01

    Full Text Available FUNDAMENTO: Os inibidores da enzima conversora de angiotensina (IECA reduzem o risco de óbito, infarto agudo do miocárdio (IAM e acidente vascular encefálico (AVE em portadores de doença coronariana. No entanto, não há consenso quanto à sua indicação em pacientes que serão submetidos à cirurgia de revascularização miocárdica (CRM. OBJETIVO: Avaliar a relação entre uso pré-operatório de IECA e eventos clínicos após realização da CRM. MÉTODOS: Estudo de coorte retrospectivo. Foram incluídos dados de 3.139 pacientes consecutivos submetidos à CRM isolada em hospital terciário brasileiro, entre janeiro de 1996 e dezembro de 2009. O seguimento dos pacientes foi realizado até a alta hospitalar ou óbito. Desfechos clínicos no pós-operatório foram analisados entre os usuários e os não-usuários de IECA no pré-operatório. RESULTADOS: Cinquenta e dois por cento (1.635 dos pacientes receberam IECA no pré-operatório. O uso de IECA foi preditor independente da necessidade de suporte inotrópico (RC 1,24, IC 1,01-1,47; P=0,01, de insuficiência renal aguda (IRA, RC 1,23, IC 1,01-1,73; P=0,04 e de evolução para fibrilação atrial (FA, RC 1,32, IC 1,02-1,7; P=0,03 no pós-operatório. A mortalidade entre os pacientes que receberam ou não IECA no pré-operatório foi semelhante (10,3 vs. 9,4%, P=0,436, bem como a incidência de IAM e AVE (15,6 vs. 15,0%, P=0,694 e 3,4 vs. 3,5%, P=0,963, respectivamente. CONCLUSÃO: O uso pré-operatório de IECA foi associado a maior necessidade de suporte inotrópico e maior incidência de IRA e FA no pós-operatório, não estando associado ao aumento das taxas de IAM, AVE ou óbitoBACKGROUND: Angiotensin-converting enzyme (ACE inhibitors reduce the chance of death, myocardial infarction (MI and cerebrovascular accident (CVA in patients with coronary disease. However there is no consensus as to its indication in patients undergoing coronary artery bypass grafting (CABG. OBJECTIVE: To

  20. Ligninases production by Basidiomycetes strains on lignocellulosic agricultural residues and their application in the decolorization of synthetic dyes Produção de ligninases por linhagens de fungos Basidiomicetos usando resíduos agrícolas lignocelulósicos e aplicação das enzimas na descoloração de corantes sintéticos

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    Eleni Gomes

    2009-03-01

    . byrsina produziu a maior quantidade de lacase (200 U mL-1 enquanto que Lentinus sp. foi o melhor produtor de manganês peroxidase (MnP e lignina peroxidase (LiP (7 e 8 U mL-1, respectivamente, quando cultivados em meio composto por farelo de trigo. A avaliação do efeito da suplementação de nitrogênio do substrato sólido lignocelulósico (palha de arroz indicou um aumento de 3 a 4 vezes na produção de lacase. A caracterização das enzimas mostrou que as lacases apresentaram atividade ótima em pH 3,0-3,5 e foram estáveis em pH de neutro a alcalino. O pH ótimo para atividade de MnP e LiP foi de 3,5 e entre 4,5 e 6,0, respectivamente. Todas as linhagens produziram lacase com atividade ótima a 55-60°C, enquanto as peroxidases apresentaram atividades máximas entre temperaturas de 30 e 55°C. A aplicação das soluções enzimáticas brutas, obtidas pelo cultivo das linhagens em meio de farelo de trigo, em testes de descoloração de corantes sintéticos de diferentes grupos químicos levou a mais 70% de perda de cor dos corantes RBBR e de cybacron blue 3GA, em 6h de tratamento. Os dados obtidos indicaram que as soluções enzimáticas contendo ligninases produzidas pelas linhagens de basidiomicetos estudadas promoveram a descoloração de corantes sintéticos.

  1. Análise da tendência temporal de dano renal agudo entre pacientes graves conforme polimorfi smos I/D e -262A > T da enzima conversora da angiotensina Temporal trends in acute renal dysfunction among critically ill patients according to I/D and -262A > T ACE polymorphisms

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    José Alberto Rodrigues Pedroso

    2010-06-01

    Full Text Available A síndrome de disfunção de múltiplos órgãos e sistemas (DMOS e a disfunção renal aguda compartilham muitos dos fatores fisiológicos envolvidos em seu desenvolvimento. Estudos recentes correlacionam suscetibilidades individuais, determinadas geneticamente, à disfunção de órgãos em pacientes criticamente enfermos, situação em que o gene da enzima conversora da angiotensina (ECA poderia ser um candidato para elucidar predisposição ou risco genético. Nosso objetivo foi examinar os efeitos da presença de dois polimorfismos, I/D e -262A > T, na disfunção renal em pacientes agudamente graves do Sul do Brasil. O escore SOFA (sequential organ failure assessment à admissão e a tendência da função renal (medida pelo escore renal diário do SOFA foram determinados em pacientes de unidade de terapia intensiva (UTI. Um total de 153 pacientes adultos (79 homens foi incluído no estudo. Houve monitoração diária da função renal durante toda a permanência na UTI e também pós-UTI. Observou-se a progressão para insuficiência renal (SOFA 3 e 4 nos primeiros sete dias de internação em UTI, bem como necessidade de diálise. As frequências genotípicas gerais em nossa amostra foram II = 0,17; ID = 0,46; DD = 0,37; e AA = 0,30; AT = 0,55; TT = 0,15; e as frequências alélicas foram I = 0,40, D = 0,60; e A = 0,56; T = 0,44. Este é o primeiro estudo para verificar a influência de polimorfismos I/D e -262A > T da ECA em disfunção renal aguda em pacientes críticos. Nenhuma associação significativa foi encontrada entre os genótipos ou as frequências alélicas e a evolução da função renal. Os polimorfismos I/D e -262A > T da ECA não têm impacto significativo sobre a evolução da função renal durante a primeira semana de internação na UTI nem exercem qualquer influência sobre a mortalidade em pacientes graves.Multiple organ failure syndrome and acute renal dysfunction share many of physiologic factors involved in

  2. NUTRIENT DIGESTIBILITY AND PERFORMANCE IN BROILER CONSUMING DIETS FORMULATED WITH DIFFERENT FIBER LEVELS AND SUPLEMENTED WITH ENZYMATIC COMPLEX DIGESTIBILIDADE DOS NUTRIENTES E DESEMPENHO DE FRANGOS DE CORTE CONSUMINDO DIETAS FORMULADAS COM DIFERENTES NÍVEIS DE FIBRA E SUPLEMENTADAS COM ENZIMAS EXÓGENAS

    Directory of Open Access Journals (Sweden)

    Bárbara Karolina Ratier da Silva

    2008-12-01

    -galactosidase, celulase, amilase, protease. No primeiro experimento (14 a 19 dias de idade dos animais, distribuíram-se aleatoriamente 190 aves em arranjo fatorial 2x2 (fibra x enzima, em gaiolas metabólicas com 9-10 aves/gaiola, cinco gaiolas por tratamento. Avaliaram-se a metabolizabilidade (MET da matéria seca (MS, a proteína bruta (PB e a energia (E, os coeficientes de digestibilidade total aparente (CDT da gordura (G e a fibra em detergente ácido (FDA,a  energia metabolizável aparente (EMA e o desempenho. Quatro repetições de cada tratamento foram mantidas para o segundo experimento. No 21º dia de idade das aves, após adaptação ao consumo das dietas com indicador, abateram-se os frangos abatidos e colheu-se conteúdo de íleo para avaliação do coeficiente de digestibilidade ileal aparente (CDI da MS, PB, E, G e peso dos cecos. O maior nível de fibra resultou em menor MET da MS, E, PB, e menor no CDT da G e FDA (P<0,05, assim como também menor CDI da MS e E (P<0,01. A suplementação enzimática reduziu o efeito da fibra sobre MET da MS, E, PB e CDT da FDA (P<0,05. Registrou-se maior peso vazio de cecos para os animais que consumiram dieta com alta fibra (P<0,01, assim como menor ganho de peso (P<0,03 e pior conversão alimentar (P<0,01. O desempenho dos animais teve maior relação com a digestibilidade ileal aparente dos nutrientes do que com a digestibilidade total aparente.

    PALAVRAS-CHAVES: Cecos, desempenho, digestibilidade ileal, digestibilidade total, metabolizabilidade.

  3. Influência do uso crônico dos inibidores da enzima conversora da angiotensina na hipotensão arterial após indução anestésica: é necessário suspender esse fármaco no pré-operatório? Influencia del uso crónico de los inhibidores de la enzima conversora de la angiotensina en la hipotensión arterial después de la inducción anestésica: ¿es necesario suspender ese fármaco en el preoperatorio? Influence of angiotensin-converting enzyme inhibitors on hypotension after anesthetic induction: is the preoperative discontinuation of this drug necessary?

    Directory of Open Access Journals (Sweden)

    Verônica Vieira da Costa

    2009-12-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Tem sido sugerida a suspensão de medicamentos como os inibidores da enzima conversora de angiotensina (IECA com base em relatos de hipotensão arterial durante a anestesia. Isso pode implicar em maior risco de picos hipertensivos no intraoperatório, com efeitos deletérios para o paciente. O objetivo deste estudo foi avaliar a influência dos IECA utilizados no pré-operatório na ocorrência de hipotensão arterial durante anestesia. MÉTODO: Delineamento tipo caso controle, onde casos foram pacientes que apresentaram hipotensão arterial após indução da anestesia. Como controles foram selecionados pacientes da mesma faixa etária e sexo, submetidos à intervenção cirúrgica no mesmo período dos casos e que não apresentaram hipotensão arterial. As variáveis de interesse: idade, sexo, porte cirúrgico, diagnóstico prévio de hipertensão arterial sistêmica (HAS, uso de IECA, estado físico (ASA, sangramento no intraoperatório, técnica anestésica e tempo cirúrgico. RESULTADOS: 40 pacientes apresentaram hipotensão arterial, num total de 2.179 operações. Desses, 20 usaram IECA no dia da operação. O grupo controle foi composto por 171 pacientes, dos quais 11 usaram IECA. Na análise univariada foi encontrada associação entre hipotensão arterial e idade avançada (p JUSTIFICATIVA Y OBJETIVOS: En base a relatos de hipotensión arterial durante la anestesia, se ha sugerido la suspensión de medicamentos como los inhibidores de la enzima conversora de angiotensina (IECA. Eso puede redundar en un riesgo más elevado de picos hipertensivos en el intraoperatorio y con efectos perjudiciales para el paciente. El objetivo de este estudio, fue evaluar la influencia de los IECA utilizados en el preoperatorio si surge la hipotensión arterial durante la anestesia. MÉTODO: Delineamiento de tipo caso control, donde los casos fueron pacientes que presentaron hipotensión arterial después de la inducción de la

  4. Otimização das condições de cultivo para a produção de amilases pelo termofílico Bacillus sp. e hidrólise de amidos pela ação da enzima Optimization of culture conditions for the production of amylases by thermophilic Bacillus sp. and hydrolysis of starches by the action of the enzymes

    Directory of Open Access Journals (Sweden)

    Raquel Vieira de Carvalho

    2008-06-01

    Full Text Available A otimização das condições de cultivo para a produção de α-amilase por um termofílico Bacillus sp. cepa SMIA-2 foi realizada. Além disso, a hidrólise enzimática do amido, proveniente de várias fontes tais como batata, mandioca e milho, foi também investigada. A produção de α-amilase por Bacillus sp. SMIA-2, cultivado em meio líquido contendo amido (5 g.L-1 como fonte de carbono e suplementado com 0,5 g.L-1 de proteínas do soro de leite e 2 g.L-1 de peptona, alcançou o máximo em 32 horas com níveis de 37 U.mL-1. O microrganismo foi capaz de utilizar diversas fontes de carbono, porém a atividade da amilase variou com cada fonte. O amido foi a melhor fonte de carbono para a secreção da amilase, enquanto a sacarose, lactose, maltose, galactose e glicose não foram muito efetivas. Uma redução na concentração de amido de até 2,5 g.L-1 no meio de cultura melhorou o crescimento do organismo e a atividade enzimática. Em altas concentrações de amido, a produção da enzima foi comparativamente menor. Em relação às fontes de nitrogênio orgânico e inorgânico, a peptona (2 g.L-1 foi considerada a melhor. Considerando a quantidade de proteínas do soro de leite no meio de cultivo, a concentração de 0,25 g.L-1 foi considerada a mais efetiva para a secreção da α-amilase pelo microrganismo. A produção máxima da atividade enzimática foi observada a 50 °C e pH 8,5. A enzima foi capaz de degradar todos os amidos testados. A hidrólise do amido de batata resultou num alto rendimento de açúcares redutores em comparação às outras fontes de amido. Amido solúvel e amido de mandioca ocuparam, respectivamente, a segunda e terceira posição em relação à liberação dos açúcares redutores, enquanto que a amilase estudada mostrou apenas uma ligeira afinidade pelo amido de milho. Com o aumento da temperatura da reação para 70 °C, a hidrólise dos substratos, com exceção do amido solúvel, resultou em maiores

  5. Role for a Steroid Sulfontransferase (SULT2B) in the Intratumoral Androgen Metabolism and in Prostate Cancer

    Science.gov (United States)

    2015-10-01

    Defense 06-09;09-12 Member, Biology of Aging Review Committee, National Institute on Aging, NIH 2008 Panel Member, AACR Centennial Pre- and Post...e. Drug-herb interaction i) St. John’s Wort, PXR, CAR, CYP3A4: The phytochemical hyperforin, which confers the anti- depressant activity of St

  6. Transmission differentials for multible pathogens as inferred from their prevalence in larva, nymph and sult of Ixodes ricinus (Acari: Ixodidae)

    DEFF Research Database (Denmark)

    Jensen, Per M.; Christoffersen, Christian S.; Moutailler, Sara

    2017-01-01

    Ixodes ricinus serves as vector for a range of microorganisms capable of causing clinical illness in humans. The microorganisms occur in the same vector populations and are generally affected by the same tick-host interactions. Still, the instars have different host preferences which should...

  7. Comparative assay of glutathione S-transferase (GSTs) activity of excretory-secretory materials and somatic extract of Fasciola spp parasites.

    Science.gov (United States)

    Alirahmi, Heshmatollah; Farahnak, Ali; Golmohamadi, Taghi; Esharghian, Mohammad Reza

    2010-01-01

    Fascioliasis is a worldwide parasitic disease in human and domestic animals. The causative agents of fascioliasis are Fasciola hepatica and Fasciola gigantica. In the recent years, fasciola resistance to drugs has been reported in the many of publications. Fasciola spp has detoxification system including GST enzyme which may be responsible for its resistance. Therefore , the aim of the study was to assay of GST enzyme activity in fasciola parasites. Fasciola gigantica and Fasciola hepatica helminths were collected from abattoir as a live and cultured in buffer media for 4 h at 37 °C. Excretory-Secretory products were collected and stored in -80◦C. F. gigantica and Fasciola hepatica were homogenized with homogenizing buffer in a glass homogenizer to prepare of somatic extract. Suspension was then centrifuged and supernatant was stored at -80°C. In order to assay the enzyme activity, excretory-secretory and somatic extracts in the form of cocktails (potassium phosphate buffer, reduced glutathione and 1-chloro-2,4-dinitrobenzene substrates) were prepared and their absorbance recorded for 5 minutes at 340 nm. The total and specific GST activity of F. gigantica somatic and ES products were obtained as 2916.00, 272.01 micromole/minute and 1.33, 1.70 micromole/minute/mg protein, respectively. Fasciola hepatica also showed 2705.00, 276.86 micromole/minute and 1.33, 1.52 micromole/minute/mg protein, respectively. These results are important for analysis of parasite survival / resistance to drugs which use for treatment of fascioliasis.

  8. Inibidor da ECA e concentrações do peptídeo natriurético do tipo B, em idosos com insuficiência cardíaca Inhibidor de la enzima conversora de la angiotensina y concentraciones del péptido natriurético de tipo B, en personas adultas mayores con insuficiencia cardiaca ACE inhibitors and plasma B-type natriuretic peptide levels in elderly patients with heart failure

    Directory of Open Access Journals (Sweden)

    Felicio Savioli Neto

    2009-05-01

    Full Text Available FUNDAMENTO: Ensaios clínicos demonstraram os benefícios dos inibidores da ECA (IECA na atividade neuro-hormonal e na capacidade funcional de pacientes com insuficiência cardíaca (IC, com a magnitude desses efeitos sendo proporcional à dose desses agentes. Entretanto, a sistemática exclusão dos idosos, observada na maioria desses estudos, tem questionado a validação e incorporação de tais resultados na população geriátrica. OBJETIVO: Avaliar os efeitos de diferentes doses de quinapril, um IECA com meia vida biológica >24 horas, nas concentrações plasmáticas do PNB, nas distâncias percorridas no teste da caminhada de 6 minutos (TC-6 min e na incidência de reações adversas, em idosos com IC sistólica. MÉTODOS: Foram avaliados 30 pacientes (76,1 ± 5,3 anos; 15 mulheres, IC II-III (NYHA, FE ventricular esquerda FUNDAMENTO: Ensayos clínicos revelaron los beneficios de los inhibidores de la enzima conversora de la angiotensina (IECA en la actividad neurohormonal y en la capacidad funcional de pacientes con insuficiencia cardiaca (IC. La magnitud de esos efectos fue proporcional a la dosificación de esos agentes. Sin embargo, la sistemática exclusión de las personas adultas mayores, observada en la mayoría de esos estudios, ha conllevado al cuestionamiento de la validación e incorporación de dichos resultados en la población geriátrica. OBJETIVO: Evaluar los efectos de diferentes dosis de quinapril, un IECA con vida media biológica >24 horas, en las concentraciones plasmáticas del péptido natriurético de tipo B (PNB, en las distancias recorridas en el test de marcha de 6 minutos (TM6m y en la incidencia de reacciones adversas, en personas adultas mayores con IC sistólica. MÉTODOS: Se evaluaron a 30 pacientes (76,1 ± 5,3 años; 15 mujeres, IC II-III (NYHA, fracción de eyección (FE ventricular izquierda BACKGROUND: Clinical trials have demonstrated the benefits of ACE inhibitors (ACEI in the neurohormonal

  9. The Use of Copper- 64 in the Investigation of Reaction Mechanisms of Enzymes, Particularly as Related to Food Processing; Emploi de Cuivre-64 dans l'Etude des Mecanismes de Reaction des Enzymes, Notamment en Ce Qui Concerne la Preparation des Denrees Alimentaires; ПРИМЕНЕНИЕ МЕДИ-64 ДЛЯ ИССЛЕДОВАНИЯ МЕХАНИЗМОВ ФЕРМЕНТАТИВНЫХ РЕАКЦИЙ, СВЯЗАННЫХ С ОБРАБОТКОЙ ПИЛИ; Empleo de Cobre-64 en el Estudio de los Mecanismos de Reacciones Enzima Ticas de Interes para la Elaboracion de Alimentos

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Jr., J. C.; McLemore, T. A. [Southern Regional Research Laboratory, New Orleans, LA (United States)

    1963-03-15

    concentration effective de l'enzyme, qui resulte vraisemblablement de l'elimination ou de la liaison du cuivre de son groupe prothetique. Il a ete demontre, en utilisant du cuivre-64 in vitro, que dans une solution en repos l'ion cuivre peut former un complexe ou faire l'objet d'un echange avec le cuivre de l'enzyme et que, dans les solutions oxydantes, une quantite supplementaire d'ions cuivre peut rentrer dans le complexe. Les complexes du type Cu-o-quinone ont des constantes de formation plus elevees que les complexes du type Cu-p-quinone. On a observe que la quantite d'ions cuivre rentrant dans le complexe diminuait lorsque les ions etaient ajoutes a une solution oxydante apres le commencement de la polymerisation des produits de reaction du type o-quinone. Les auteurs examinent, du point de vue mathematique, la cinetique des phenomenes des echanges et de la formation de complexes entre les ions de cuivre et les produits des enzymes ou les produits de reaction. (author) [Spanish] Las enzimas oxidantes de los tejidos vegetales se encuentran a menudo latentes o solo presentan una leve actividad durante el estado de reboso, activandose al sufrir el tejido una lesion o al separarlas de el. En la elaboracion de alimentos, este efecto acelera la oxidacion de los substratos naturales y provoca polimerizaciones que alteran el color de los tejidos. Las principales enzimas que catalizan estas reacciones son las cuproxidasas. La inactivacion de la reaccion se debe, entre otras causas, a una disminucion de la concentracion efectiva de la enzima, probablemente por eliminacion o por fijacion del cobre de su grupo prostetico. Con ayuda de cobre 64 in vitro se demostro que en una solucion en reposo, el ion cuprico puede complejarse o intercambiarse con el cobre de la enzima, o ambas cosas, y que las soluciones oxidantes pueden formar un complejo con una cantidad adicional de ion cuprico. Las constantes de formacion de los complejos del tipo Cu-o-quinona son mas elevadas que las de los

  10. Atividade eletrocatalítica de sistemas biomiméticos da enzima catalase

    Directory of Open Access Journals (Sweden)

    Iorquirene de Oliveira Matos

    2011-09-01

    Full Text Available In this work, we describe the immobilization of the dinuclear compound [Cu2(apyhist2Cl2](ClO42 (1 and its derived cations complexes, obtained in water solution or by deprotonation of the imidazolate moiety in the ligand leading to a cyclic tetranuclear species, in the Nafion® membrane on glass carbon electrode surface. After that, we studied the influence of the equilibrium in the electrocatalytic activity towards the reduction of H2O2 in the development of an amperometric sensor for the analytical determination of hydrogen peroxide. This strategy proved successful, and the electrochemical behaviour of the all complexes formed within the Nafion® coatings was characterized. We also provide evidence that its related cyclic tetranuclear imidazolate-bridged complex acts as a catalysts for the intramolecular, two-electron reduction of H2O2.

  11. Fitasa y enzimas fibrolíticas en dietas para cerdos con diferentes sustratos

    Directory of Open Access Journals (Sweden)

    Mario Alberto Ávalos Castro

    2011-01-01

    Full Text Available El objetivo del estudio fue evaluar la adición de fitasa (F y actividades de pectinasa, glucanasa y hemicelulasa (PGH en dietas sorgo-soya-canola, y xilanasa (X en dietas con grano seco de destilería con solubles (GSDS sobre la digestibilidad ileal y fecal de nutrientes (Exp 1 y el comportamiento productivo (Exp 2 en cerdos en crecimiento finalización. En el Exp 1 se formularon dos dietas basales (B1, sorgo-soya-canola y B2, sorgo-soya-canola + GSDS y los tratamientos fueron, 1 B1+F, 2 B1+F+PGH, 3 B2+F, 4 B2+F+PGH, 5 B2+F+X, y 6 B2+F+PGH+X. El Exp 2 incluyó cuatro tratamientos, 1 Testigo positivo (sorgosoya- canola con energía normal, 2 Igual que 1, pero bajo en energía, 3 Igual que 2 +F+PGH, 4 Igual que 3 +GSDS +X. En el Exp 1, la digestibilidad de la energía a nivel ileal se mejoró (P<0.05 con +F+PGH, +F+X y +F+PGH+X, y a nivel fecal se mejoró (P<0.05 con +F+X. La PGH liberó 122 kcal a nivel ileal y la X liberó 147 y 132 kcal de ED/kg de alimento a nivel ileal y fecal. En el Exp 2, la eficiencia alimenticia fue mayor (P<0.01 en el testigo positivo y el tratamiento bajo en energía +F+PGH, pero este último tuvo mayor (P<0.05 eficiencia energética. El valor energético de los GSDS se mejoró por la adición de F, PGH y X, pero la respuesta en crecimiento observada en el presente trabajo no fue consistente.

  12. Uso de las enzimas digestivas en el tratamiento de la diarrea persistente

    Directory of Open Access Journals (Sweden)

    Arnaldo Izquierdo Estévez

    1998-03-01

    Full Text Available Se realizó un estudio prospectivo de corte transversal, con el propósito de conocer la medida en que los fermentos pancreáticos totales administrados oralmente, favorecen la evolución de la enfermedad, en los niños menores de 1 año con diarrea persistente, ingresados en el Servicio de Gastroenterología del Hospital Pediátrico Docente "Ángel A. Aballí" en el período de enero a abril de 1996. Los resultados permiten afirmar la reducción del número de deposiciones y el incremento efectivo de peso al 3er. día de tratamiento, así como la mejoría de los síntomas asociados con la diarrea, sin efectos secundarios.A prospective cross-sectional study aimed at finding out to what extent the orally-administered total pancreatic fermets influence over the development of diarrhea disease in under one-year old children admitted with persistent diarrhea to the Gastroenterology Service Unit of «Ángel A. Aballí» Teaching Pediatric Hospital from January to April 1996 was performed. Results showed the reduction in the number of stools, the effective weight gain on the 3rd day of treatment as well as the improvement of diarrhea-related symptoms without side effects.

  13. Acth e enzimas na supra-renal ACTH and enzymes in adrenal gland

    Directory of Open Access Journals (Sweden)

    H. Povoa Junior

    1974-01-01

    Full Text Available Estudou-se a atividade da ceruloplasmina, adenosina desaminase (AD e transaminases glutâmico oxalacética (TGO e glutâmico pirúvica (TGP na supra-renal de ratos normais e injetados previamente (24 horas antes com uma injeção única, por via intraperitoneal, de ACTH em doses de 0,5 e 1,2 un. internacionais. observou-se uma elevação estatisticamente significativa das TGO e ceruloplasmina enquanto a AD sofria diminuição sensível em sua atividade.Activities of several enzymes have been studied in rat adrenal glands after ACTH injection. Activity of glutamic oxalacetic transaminase increases significantly after ACTH. The same was observed with ceruloplasmin. Adrenosine desaminase inthe same gland was decreased after administration of this hormone.

  14. Sistemas microfluídicos amperométricos utilizando enzimas imobilizadas

    OpenAIRE

    Luís Marcos Cerdeira Ferreira

    2011-01-01

    Este trabalho descreve o desenvolvimento de um sistema microfluídico, contendo, como componente principal, um reator enzimático constituído de um microcanal fabricado em substrato de poli(metacrilato de metila) e um sistema amperométrico como detector. Para a construção de microcanais foi utilizando equipamento de usinagem a laser de CO2 para escavar os microcanais, que a seguir foram selados termicamente. A superfície interna desse microcanal foi submetida à modificação química com poli(etil...

  15. Efeito de enzimas hidrolíticas no comportamento reológico do óleo de palma cru

    OpenAIRE

    FREITAS,Suely P.; SILVA,Fernando C.; LAGO,Regina C.A.; COURI,Sonia

    1998-01-01

    No processamento tradicional de extração de óleo de palma, uma quantidade substancial do produto é perdida na fibra - durante a etapa de prensagem do fruto - e na borra - durante a etapa de clarificação do óleo cru. A viscosidade deste constitui a principal dificuldade de separação do óleo dos demais componentes da mistura. A eficiência de recuperação do óleo é usualmente melhorada por adição de água, no tanque de clarificação. Neste trabalho avaliou-se os efeitos da diluição e do tratamento ...

  16. Estudio del efecto inhibitorio de extractos de Salvia scutellarioides sobre la actividad de la enzima convertidora de angiotensina

    Directory of Open Access Journals (Sweden)

    Gina Méndez-Callejas

    2009-12-01

    Full Text Available Study of the inhibitory effect of Salvia scutellarioides extracts on the activity of the angiotensin-converting enzyme. Objective. Toidentify groups of secondary metabolites of Salvia scutellarioides present in the fraction with the greatest inhibitory effect on the activity ofthe angiotensin-converting enzyme (ACE. Materials and methods. Dry plant material was used to prepare ethanolic extracts that werethen concentrated and separated by column chromatography using solvents of different polarity (petroleum ether, dichloromethane, diethylether and ethanol. Subsequently, lung tissue isolated from Wistar rats was broken and centrifuged in order to separate the soluble material.Proteins found in the supernatant were separated using a Sephacryl column; a pool was made with the fractions that showed activity withhippuryl-L-histidyl-L-leucine (HHL, the substrate of the ACE. This enzyme extract was used to measure the effect of plant extractsobtained from S. scutellarioides on the ACE activity. Results: The fraction of ethyl acetate (T2 showed a greater inhibitory effect on theACE activity. Metabolites found in T2 fraction were: tannins, cardiac glycosides, coumarins, and quinones. Conclusion. An antihypertensiveeffect was found for the plant species Salvia scutellarioides by studying the inhibitory effect on the ACE activity. Several groups ofsecondary metabolites present in the T2 fraction were identified, which could be responsible for this effect.

  17. Selección de cepas productoras de enzimas ligninolíticas nativas del Valle del Yaqui

    Directory of Open Access Journals (Sweden)

    S.R. Maldonado-Bustamante

    2017-01-01

    Full Text Available Introducc ión: Las fibras lignocelulósicas están compuestas por tres polímeros: celulosa, hemicelulosa y lignina. El biopulpeo es un pretratamiento, previo al proceso de pulpeo físico químico, cuyo fin es lograr la deslignificación parcial del complejo lignocelulós ico por la acción de hongos, debido a que los hongos tienen un complejo enzimático formado por: ligno peroxidasas (LiP, lacasas (Lac, manganeso peroxidasas (MnP, y xilanasas (Xil. Las cepas nativas tienen la habilidad de deslignificar el material ligno celulósico como paja de trigo o madera, entre otros. Método: Se trabajó con diez cepas de la colección COLMENA del Laboratorio de Biotecnología del Recurso Microbiano del Instituto Tecnológico de Sonora. La selección de cepas se realizó escogiendo las que presentaron mayor índice de potencia (I.P., obtenido a través de la comparación del halo de actividad enzimática contra el halo de crecimiento de la cepa, a los 14 días de incubación utilizando el software Image J 1.44. Resultados: De las diez cepas eva luadas , la mejor para la producción de LiP fue TSM35 con un I.P. de 3.83±0.29, para Lac y Xil ; la cepa TSO46 obtuvo valores de con un I.P. de 20.37±2.70 y 1.38±0.00 respectivamente . Con este estudio se determinó el potencial de incorporar cepas nativas pa ra el pretratamiento de biopulpeo previo a un un proceso de deslignificación físico químico. Discusiones o Conclusiones: Se logró determinar que tres cepas tienen actividad ligninolítica en medio sólido por excreción de LiP, Lac y Xil , por lo que tiene n potencial para incorporarlos como pretratamiento en un proceso de deslignificación.

  18. BIOSSENSOR ELETROQUÍMICO BASEADO NA ENZIMA TIROSINASE PARA A DETERMINAÇÃO DE FENOL EM EFLUENTES

    Directory of Open Access Journals (Sweden)

    Dejane P. C. de Oliveira

    2015-08-01

    Full Text Available AbstractThis work describes the development of a biosensor based on the tyrosinase enzyme (Tyr for the determination of phenol (PHEN in laboratory effluent samples derived from ammoniacal nitrogen analysis of the water samples from the Muquém dam in the city of Cariús, CE, using square-wave voltammetry (SWV. The electrode modification consisted of the immobilization of gold nanoparticles, multi-walled carbon nanotubes, cobalt phthalocyanine, and Tyr on a glassy carbon electrode. The electrolyte, pH, enzyme quantity, and voltammetric parameters were optimized to detect PHEN. The analytical curves presented a linear range from 4.97 × 10-6 mol L-1 to 6.10 × 10-5 mol L-1, and the detection limit (DL and quantitation limit (QL values were 4.81 × 10-6 mol L-1 and 4.97 × 10-6mol L-1, respectively. The repetition of measurements with the same biosensor and repetition for three other prepared biosensors exhibited a relative standard deviation (RSD of 5.50 and 1.75%, respectively. The percentage recovery of PHEN in effluent samples varied from 86.40 to 105.04%. The stability of the biosensor was evaluated (at 21 days with satisfactory results, showing 97.86% of the initial response. Moreover, the DL and recovery percentages agreed with the established values from CONAMA and ABNT, respectively. Thus, the electrode configuration developed seems a promising tool in the detection and quantification of PHEN in complex samples.

  19. Variaciones de la enzima fosfatasa alcalina en la pulpa dental Variations of alkaline phosphatase enzyme in the dental pulp

    Directory of Open Access Journals (Sweden)

    Zoraida Pons Pinillos

    2005-08-01

    Full Text Available En las últimas décadas, numerosas investigaciones se han dedicado al estudio de los mecanismos potenciales implicados en el desarrollo de la caries dental y su prevención, sin embargo, a pesar de haber disminuido gradualmente el índice de caries en la población, son muchos los pacientes que necesitan tratarse la caries dental, tal es así que continuamente se están utilizando diferentes materiales en la búsqueda de aquel que ante una agresión a la pulpa, ayude a una respuesta biológica de la misma, conservando de esta forma su integridad. De ahí la importancia de la actividad de la fosfatasa alcalina de la pulpa en el proceso carioso, como una reacción ante el hidróxido de calcio que continuamente se está usando en toda la red docente-asistencial del país. Se seleccionaron 50 dientes monorradiculares, con pulpa viva y con caries de segundo, tercer y cuarto grado y 50 dientes sanos de pacientes de diferentes edades. Se extrajo la pulpa de cada diente y se realizaron improntas (3 por cada muestra, una de las cuales se procesó para obtener orientación morfológica, y las otras 2 para valorar la actividad de la fosfatasa alcalina. Para esto se utilizaron 2 métodos: el de calcio cobalto y el de alpha naftol fosfato de Gomori. Como resultado, se obtuvo que la pulpa tiene más actividad enzimática en caries profunda y que la edad del paciente no determina el aumento o disminución de dicha actividad.In the last decades, numerous investigations have been made on the study of potential mechanisms involved in the development of dental caries and their prevention. However, in spite of the gradual reduction of dental caries in the population, a lot of patients need to have their dental caries treated and different materials are continuously used searching for one that before the aggression to the pulp helps it to give a biological response, conserving this way its integrity. That's why the activity of the alkaline phosphatase of the pulp in the caries process is important as a reaction to the calcium hydroxide that is constantly utilized in the teaching-health service network of the country. 50 monoradicular teeth with living pulp and with caries of second, third and fourth degree, and 50 sound teeth from patients of different ages were selected. The pulp of each tooth was extracted and impressions were made (3 per sample. One of them was processed to obtain morphological guidance and the other two to assess the activity of alkaline phosphatase. The cobalt calcium method and Gomori's alpha naphthol phosphate method were used to this end. As a result, it was proved that the pulp has a higher enzymatic activity in deep caries and that the age of the patient does not determine the increase or decrease of this activity.

  20. Mejoramiento de la textura de un producto reconstituido de trozos de camarón empleando la enzima Transglutaminasa

    Directory of Open Access Journals (Sweden)

    Álvarez-Anchundia, Denisse

    2017-09-01

    Full Text Available The Ecuadorian Coast hosts different species of shrimp of high quality and commercial interest, among them Litopenaeus vannamei stands out due to its greater adaptation in aquaculture. Shrimp fulfills the highest potential of raw material, when it is transformed into products that contain greater added value due to its organoleptic characteristics and excellent quality, in the wide range of seafood. In addition, part of the shrimp harvested or extracted from the sea is not exported, since there is a sub-product that does not meet the requirements of importers because it is cut up and is known as local sale or broken shrimp. The enzyme transglutaminase with its properties of binding protein is a key ingredient to reconstitute these pieces of low commercial value. The objective of this study was to develop a reconstituted food product based on pieces of shrimp with better adhesion and compaction in the crustacean meat protein. The acceptability of this enzyme in the processed product was evaluated by sensorial analysis, obtaining more preference the products with transglutaminase for their texture and flavor, it should be noted that the organoleptic characteristics and the nutritional content of the shrimp were not altered according to the analyzes carried out.

  1. Hipoparatireoidismo primário manifestando-se com aumento de enzimas musculares Primary hypoparathyreoidism with raised muscle enzymes

    Directory of Open Access Journals (Sweden)

    Simone Appenzeller

    2005-08-01

    Full Text Available Os autores relatam o caso de um jovem de 18 anos de idade com fraqueza muscular generalizada, cãibras e crises convulsivas, tratado com corticosteróides por oito anos em decorrência de um diagnóstico de polimiosite, sem melhora clínica. Ao exame físico apresentava força muscular normal, ausência de atrofias musculares, diminuição de reflexos tendíneos profundos e presença do sinal de Chvostek e Trousseau. A hipótese diagnóstica inicial foi de miopatia metabólica e a investigação laboratorial revelou cálcio sérico e urinário diminuídos e dosagem de paratormônio (PTH indetectável. O diagnóstico final foi de hipoparatireoidismo, tendo sido o paciente tratado com cálcio endovenoso. A tomografia de crânio demonstrou calcificações difusas, características da síndrome de Fahr. O paciente recebeu alta assintomático com carbonato de cálcio e colecalciferol.The authors report a case of an 18-year-old boy using prednisone for eight years for a misdiagnosis of polymyositis. His complains were diffuse weakness, cramps and seizures, with progressive worsening and with no improvement despite treatment with corticosteroid. On admission, the physical examination didn't show muscular weakness or atrophy. Deep tendom reflexes were absent and Chvostek and Trousseau signs were found. The diagnosis of a metabolic myopathy was considered and further laboratory findings revealed a low serum and urinary calcium, undetectable PTH. The diagnosis of hypoparathyreoidism was made and the patient was treated with endovenous calcium. Cranial tomography revealed diffuse calcifications, suggestive of Fahr's syndrome. The patient recovered completely and was discharged with oral calcium carbonate and colecalciferol.

  2. Inmovilización de enzimas lignocelulolíticas en nanopartículas magnéticas

    Directory of Open Access Journals (Sweden)

    Jaquelina Sánchez-Ramírez

    2014-06-01

    Full Text Available Due to the need for more efficient, economical and environmentally-friendly technological processes, the use of enzymes has increased. However, reuse of enzymatic hydrolytic complex is required. The immobilization of enzymes provides a basis for stability and allows their reuse reflected in aspects of economic feasibility. Magnetic nanoparticles are a promising supports since their magnetic character allows retrieval by applying an external magnetic field. This article presents an analysis and discussion of methods of biocatalyst immobilization, emphasizing lignocellulolytic enzymes immobilized in magnetic nanoparticles and their applications for the production of high-value compounds such as bioethanol.

  3. Aplicações de enzimas na síntese e na modificação de polímeros

    Directory of Open Access Journals (Sweden)

    Marcos de Campos Cavalcanti de Albuquerque

    2014-01-01

    Full Text Available Enzymes are biological catalysts that offer great potential for use in the synthesis and modification of polymers, being more specific and greener than chemical catalysts. In this work, enzymes from the classes of hydrolases (lipase, cutinase and protease and of oxidoreductases (horseradish peroxidase, manganese peroxidase and laccase were identified as the main biocatalysts responsible for the synthesis of polymers. Biocatalysis can potentially be part of the life cycle of several polymers, including polyesters, polyurethanes, polycarbonates, polyamides, functionalized polysaccharides and polystyrene, allowing the synthesis of specialty macromolecules for fine applications and with higher added-value than commodity polymers.

  4. Determinación del efecto inhibitorio de los polifenoles presentes en la fresa (Fragaria vesca L.) sobre la enzima alfa amilasa

    OpenAIRE

    Sosa N., Miriam; Pernía S., Tibisay; Buitrago B., Diolimar; Pérez L., Jackeline; Araujo, Liliana; Méndez de Corao, Grecia

    2004-01-01

    REVISTA DE LA FACULTAD DE FARMACIA Vol. 43, 2002 UN AÑO DE EXPECTATIVAS El 2002 se nos presenta como de grandes expectativas en todos los órdenes del acontecer de la nación venezolana, y del mundo. No obstante, y muy a pesar de los malos presagios que se ciernen sobre nuestro destino, aguardamos con esperanzas y con optimismo los retos que se nos plantean. Por esta razón la Revista de la Facultad de Farmacia continúa en su empeño por fortalecer las bases que han llevado a alca...

  5. Aplicação de quitosana como suporte para a imobilização de enzimas de interesse industrial

    Directory of Open Access Journals (Sweden)

    Adriano A. Mendes

    2011-01-01

    Full Text Available Chitosan, poly[β-(1-4-linked-2-amino-2-deoxy-D-glucose], is the N-deacetylated product of chitin which is a major component of arthropod and crustacean shells such as lobsters, crabs, shrimps, and cuttlefishes. In addition, chitosan has many significant biological and chemical properties such as biodegradability, biocompatibility and bioactivity as well as polycationic properties. Thus, it has been widely used in many industrial and biomedical applications including wastewater treatment, chromatographic support, carriers for controlled drug delivery and enzyme immobilization. This review is an insight into the exploitation of utilization of chitosan based-supports in different geometrical configurations on the immobilization of enzymes by different protocols for further application in biotransformation reactions.

  6. Cicatrização de feridas: estudo comparativo em ratos hipertensos não tratados e tratados com inibidor da enzima conversora da angiotensina

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Pessole Biondo-Simões

    Full Text Available OBJETIVO: Reconhecer a interferência do captopril na cicatrização de feridas cutâneas de ratos hipertensos. MÉTODOS: Distribuíram-se 111 ratos em quatro grupos: controle normotenso (N=30; controle hipertenso (N=30, os quais receberam 1 ml/dia de solução de cloreto de sódio a 0.9% por via oral; grupo experimento (N=31, hipertensos que receberam 7,5mg/kg/dia de captopril e um grupo aferição (N=20, 10 hipertensos e 10 normotensos, nos quais aferiu-se a pressão na aorta abdominal, no último dia de experimento. Após 15 dias de medicação, fez-se uma incisão da pele e da tela subcutânea, na região médio-dorsal dos grupos I, II e III, seguida de síntese. Ressecaram-se as cicatrizes de 10 animais de cada grupo, no 4.º, 7.º e 14.º dias após a operação, que divididas em duas partes foram enviadas para a tensiometria e para análise histológica. RESULTADOS: A pressão arterial média de 83,18 ± 7,51 mmHg nos normotensos e 151,36 ± 10,51 mmHg nos hipertensos. As cicatrizes dos hipertensos tratados e não tratados eram menos resistentes que as dos normotensos, nos tempos iniciais (p<0,05 e que ao 14.º dia as resistências se igualaram. Não houve diferença entre o grupo tratado e o não tratado. A densidade de colágeno total foi maior nos normotensos em todos os tempos (p<0,05 e não houve diferença entre hipertensos tratados e não tratados. A epitelização, a reação inflamatória e a formação do tecido de granulação foi semelhante nos três grupos. CONCLUSÕES: O captopril, em ratos, não modifica a cicatrização, ficando as diferenças relacionadas à hipertensão.

  7. Frecuencia aumentada del alelo D y el genotipo DD del gen de la enzima convertidora de angiotensina en pacientes con un primer evento coronario

    Directory of Open Access Journals (Sweden)

    Nelsy Loango

    2010-04-01

    Full Text Available Increased frequency of the D allele and the DD genotype of the angiotensin-converting enzyme in patients with a first coronaryevent. Objective. To evaluate the genotypic and allelic frequencies of the I/D polymorphism of the ACE gene and the enzymatic activityin a group of Colombian patients with myocardial infarction (MI and in a group of healthy subjects. Materials and Methods. Weexamined 41 patients diagnosed MI and admitted consecutively in the San Juan de Dios Hospital, and 39 subjects with no clinicalevidence of coronary syndrome. ACE genotypes were determined by means of the polymerase chain reaction and the enzyme activityusing spectrophotometry. Results. Polymorphism distribution among the patients was II 14.6%, ID 34.1%, and DD 51.2%, whilst inthe control group it was II 30.8%, ID 28.2% and DD 41.0%, without significant differences between groups. ID and DD subjects werecombined and after adjustment for other variables, their risk of MI was 3.5 times higher than in those subjects with the I allele (95% IC:1.2-10.4 p=0.02. Enzyme activity was higher in subjects with the D allele, except in patients with enzyme inhibitor medication.Conclusions. Results show a higher frequency of the D allele and the DD genotype in patients with a first myocardial infarction, besidesconfirming a variation in the ACE activity levels influenced by the I/D. Our findings provide evidence of an increased risk of MI inColombian subjects with the D allele.

  8. Correlación entre los niveles de Hemoglobina Glicada y las enzimas antioxidantes, en pacientes con Diabetes Mellitus Tipo 2

    OpenAIRE

    Vergaray, L.; Robles, Y.; Flores, E.; Suárez, S.

    2014-01-01

    It has been determined Glycated A1c haemoglobin, Superóxido Dismutase, Glutation peroxidase and Malondialdehide levels in 25 patients with Diabetes mellitus type 2, whom participate in the Education Program for Diabetic Patients, from Arzobispo Loayza Hospital, they were confront with 15 persons apparently healthful control group. There is a positive correlation between Glycated A1c haemoglobin - Superoxido Dismutase (r=0,164, p

  9. Degradação de deoxinivalenol (DON) e a atividade da enzima peroxidase durante fermentação submersa

    OpenAIRE

    Garda-Buffon, Jaqueline; Kupski, Larine; Badiale-Furlong, Eliana

    2011-01-01

    This work aims to evaluate deoxynivalenol degradation by Aspergillus oryzae and Rhizopus oryzae in a submerged fermentation system and to correlate it to the activity of oxydo-reductase enzymes. The submerged medium consisted of sterile distilled water contaminated with 50 μg of DON and 4 × 10(6) spore.mL-1 inoculum of Aspergillus oryzae and Rhizopus oryzae species, respectively in each experiment. Sampling was performed every 24 hours for monitoring the peroxidase specific activity, and ever...

  10. Eritrocitosis post trasplante renal y su tratamiento farmacológico: inhibidores de la enzima convertidora de angiotensina versus bloqueadores de los receptores de angiotensina en un caso

    OpenAIRE

    Duclos H,Jaime

    2000-01-01

    A 35 years old male is presented. Eight months after receiving a renal allograft his hypertension worsened and his packed red cell volume raised to 53.7%. Enalapril was started and a 500 ml phlebotomy was performed. In three occasions packed red cell volumes decreased excessively and enalapril was discontinued. Finally, the drug was replaced with losartan, normalizing blood pressure values and stabilizing packed red cell volumes. This case illustrates the different reductions in packed red ce...

  11. Inducción de la enzima triptófano 2,3 dioxigenasa por glucocorticoides y su papel en la tolerancia materna al feto

    Directory of Open Access Journals (Sweden)

    Angela Cadavid

    2004-02-01

    Full Text Available

    El mecanismo por el cual la madre no rechaza al feto, sigue siendo una incógnita en la inmunología de la reproducción. Una de las hipótesis planteadas es la inmunosupresión mediada por el catabolismo del triptófano, el cual es un amino ácido sencial para la proliferación de los linfocitos T. Una de las nzimas que cataboliza el triptófano es la triptófano 2,3 ioxigenasa (TDO.
    La TDO es inducida por los glucocorticoides en el hígado, pero aún no se conoce si estos inducen la producción de la TDO n la interfase materno fetal al interactuar con los receptores resentes en células estromales y NK; En un modelo murino, e observó que la TDO se expresa en la interfase materno etal con un pico que coincide con el de mayor actividad de egradación del triptófano, sugiriendo entonces que esta nzima puede estar involucrada en la tolerancia materna al feto.

     

     

  12. ACTIVIDAD INSECTICIDA DE ACEITES ESENCIALES DE DOS ESPECIES DE Eucalyptus SOBRE Rhyzopertha dominica Y SU EFECTO EN ENZIMAS DIGESTIVAS DE PROGENIES

    Directory of Open Access Journals (Sweden)

    Ramiro Reyes-Guzmán

    2012-01-01

    proteolítica de las progenies; sin embargo, solamente E. globulus ocasionó la muerte de éstas (P < 0.05. Al incrementar el volumen de aceite de E. camadulensis, la actividad proteolítica del insecto aumentó, incluso al mayor tiempo de exposición. Los resultados de este estudio muestran que la fracción volátil de los aceites esenciales de eucalipto, especialmente la de E. globulus, es un agente insecticida efectivo para el control de R. dominica en trigo almacenado.

  13. Degradación de aminas biógenas mediante sistemas microbianos. Identificación y caracterización de las enzimas responsables

    OpenAIRE

    Callejón Salinas, Sara

    2016-01-01

    Las aminas son compuestos ampliamente presentes en la naturaleza que contienen uno o varios sustituyentes unidos a un átomo de nitrógeno. Son compuestos endógenos de las plantas que también pueden encontrarse en frutas frescas y verduras. Sin embargo, en los alimentos, las aminas se forman fundamentalmente en los procesos fermentativos, y durante el envejecimiento y la conservación. Las aminas biógenas (AB) se originan por la descarboxilación microbiana de los correspondientes aminoácidos pre...

  14. AVALIAÇÃO DAS DIETAS SIMPLIFICADAS E SEMI-SIMPLIFICADAS, COM BASE NA MISTURA DE FORRAGEIRAS, COM E SEM ENZIMAS, PARA COELHOS EM CRESCIMENTO

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Machado

    2012-09-01

    Full Text Available The simplified and half-simplified diets are a new technology that combines economy and welfare intestinal. The main objective of this study was to evaluate the effect of simplified and half-simplified diets, with and without exogenous enzymes, on the productive performance of growing rabbits. A Reference diet, two simplified diets and eight half-simplified diets had been utilized. The main fibrous sources used were the alfalfa hay (ALH, hay from the upper third of the cassava foliage (HUTCF and cassava leaf meal (CLM, using a completely randomized design with 11 treatments and eight repetitions. The enzymes used were the carbohydrases (alpha-galactosidase, galactomanase, xylanase and beta-glucanase and phytase. The consumption of animals fed with diets with high inclusion of CLM was lower than the other. The daily weight gain was higher in animals fed with the reference diet, half-simplified diet based on HUTCF and half-simplified diets based on the mix of ALH and CLM. A positive effect of exogenous enzymes inclusion, on the performance parameters, was not observed. Based on these results we conclude that the simplified and half-simplified diets provide decrease in productive performance. Considering the proportionate economy in the cost of feed, the half simplified based on HUTCF may be an interesting alternative.

  15. Study of the interaction of enzyme Heparanase 1 (HPSE1) active with deoxyribonucleic acids; Estudo de interacao da enzima Heparanase 1 (HPSE 1) ativa com acido desoxirribonucleicos

    Energy Technology Data Exchange (ETDEWEB)

    Cid, Gisele da Silva

    2016-07-01

    The human heparanase 1 (HPSE 1) is a protein with multiple functions and has emerged as a promising therapeutic target in the context of antitumor therapy. This fact is due to its clinical relevance in the tumor development and progression, as determined by their enzymatic ability to degrade heparan sulfate (HS), the main constituent of the extracellular matrix, providing a tumor microenvironment to tumor dissemination. In addition, this protein plays a significant role in the increase of tumor cells migration ionizing radiation dose delivery in radiotherapy from the increase in the expression levels of HPSE1. In order to evaluate in more detail the functions of active HPSE1, it has been proposed to characterize the interaction of human heparanase protein 1 with deoxyribonucleic acids. Our results are original and point to a new function of HPSE1 of the endonuclease type. (author)

  16. Enzimas termoestáveis: fontes, produção e aplicação industrial Thermostable enzymes: sources, production and industrial applications

    Directory of Open Access Journals (Sweden)

    Eleni Gomes

    2007-02-01

    Full Text Available REVIEW: Living organisms encountered in hostile environments that are characterized by extreme temperatures rely on novel molecular mechanisms to enhance the thermal stability of their proteins, nucleic acids, lipids and cell membranes. Proteins isolated from thermophilic organisms usually exhibit higher intrinsic thermal stabilities than their counterparts isolated from mesophilic organisms. Although the molecular basis of protein thermostability is only partially understood, structural studies have suggested that the factors that may contribute to enhance protein thermostability mainly include hydrophobic packing, enhanced secondary structure propensity, helix dipole stabilization, absence of residues sensitive to oxidation or deamination, and increased electrostatic interactions. Thermostable enzymes such as amylases, xylanases and pectinases isolated from thermophilic organisms are potentially of interest in the optimization of industrial processes due to their enhanced stability. In the present review, an attempt is made to delineate the structural factors that increase enzyme thermostability and to document the research results in the production of these enzymes.

  17. Efecto de la aplicación de pulsos eléctricos de alta intensidad de campo sobre enzimas y vitaminas en leche

    OpenAIRE

    Bendicho Porta, Silvia

    2002-01-01

    En l'actualitat, el mètode més utilitzat per a la pasteurització d'aliments es l'aplicació decalor, encara que en aquestes darreres dècades estan sorgint tecnologies alternatives, entreles quals cal destacar l'ús dels polsos elèctrics d'alta intensitat de camp (PEAIC).En llet, s'ha vist que amb l'aplicació d'aquesta tècnica es poden aconseguir alts nivellsd'inactivació microbiana, encara que igual que en altres productes, hi ha pocs estudis sobrel'efecte que produeixen en enzims i components ...

  18. Extração e caracterização de uma enzima proteolítica do curauá (Ananas Erectifolius

    Directory of Open Access Journals (Sweden)

    Juliana Ferrari Ferreira

    2010-01-01

    Full Text Available Ananas erectifolius (curauá is a fibrous vegetable that can be found in North and Central West regions of Brazil. It is a bromeliaceae family plant which physico-chemical features provides great potential in the automobilistic industry as a source of fibers. As commonly described in other bromeliaceae species, it contains significant levels of bromelain, of high commercial value and wide range of aplications in food, pharmaceutical and cosmetics industry. In this paper, experimental tests were performed to evaluate the extraction of the proteolytic enzymes of the Ananas erectifolius under different pH and temperature conditions to determine in which ones the enzymatic activity would be the maximum for later purification of the bromelain. The two commercially available curauá varieties (white and purple were used in the experiments and the results showed the same optimal pH of 8.5 for both varieties and different temperatures of 30°C for the white one, and 10°C, 20°C and 35°C for the purple one.

  19. Modification of a cellulose derived for your application on enzyme immobilization;Modificacao de um derivado celulosico para sua aplicacao na imobilizacao de enzimas

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Elaine S.; Rodriguez, Ruben J.S.; Lamonica, Alano C., E-mail: ecarvalho@uenf.b [Universidade Estadual do Norte Fluminense Darcy Ribeiro (LAMAV/UENF), Campos dos Goytacazes, RJ (Brazil). Lab. de Materiais Avancados; Tavares, Maria Ines B. [Universidade Federal do Rio de Janeiro (IMA/UFRJ), RJ (Brazil). Inst. de Macromoleculas Profa. Eloisa Mano

    2009-07-01

    The chemical modification of (acrylamidomethyl) cellulose acetate propionate (AMCAP) was done through the technique of grafting via radical using acrylic acid as modifier, with the objective to make the polymer more hydrophilic. The structural characterization of AMCAP and modified AMCAP-H{sub 2}O{sub 2} was analysed by using the technique of {sup 13}C-nuclear magnetic resonance (NMR-{sup 13}C). By the techniques differential scanning calorimetry analysis (DSC) and thermogravimetric analysis (TGA), the thermal properties was characterized and the hydrophobic / hydrophilic character was determined by measurements of the contact angle. The results show that occurred the change intended with the introduction of acrylic acid in the side chain of the polymer, increasing the hydrophilic character on the AMCAP. (author)

  20. Enzymes evaluation for the polymeric filter cake removal; Avaliacao de enzimas para remocao de reboco formado por fluidos polimericos de base agua

    Energy Technology Data Exchange (ETDEWEB)

    Kameda, Etel; Coelho, Maria Alice Z. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Escola de Quimica; Langone, Marta A.P. [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Inst. de Quimica; Queiroz Neto, Joao C. de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    In the drilling wells in horizontal or complex configurations, the drilling fluid contact with the productive zone can reduce the productivity by fluid invasion in the borehole wall. Drilling fluids usually comprise natural polymers as starch and xanthan gum. These polymers are deposited as the filter-cake on the wellbore wall. A common approach to remove this filter-cake is the application of acids or strong oxidative solutions. However, these are non-specific species which will react with any encountered that is acid soluble or oxidizable. An alternative is the use of enzymatic preparations that are able to hydrolyze such polymers. The enzymes catalyze only certain specific substrates, are inherently environmentally friendly, the enzymatic degradation rate is slower than that achieved by the oxidative species, so the enzymes produces an uniform filter cake degradation. In this work, the kinetic behaviors of an enzymatic filter-cake breaker and a commercial thermo stable enzymatic complex were analyzed. Both kinetic profiles were very similar, as well as its electrophoresis analysis. The protein in each product showed identical molecular weight. The commercial enzymatic complex stability remained 58.56% of enzymatic activity after 30 days at 40 deg C. Stability at wellbore conditions can be considered similar for both products. At 65 deg C they showed the same enzymatic activity after 8 hours. After 3 hours at 80 deg C, the commercial enzymatic complex remained 29.89% of the initial activity and the filter-cake breaker 61.73%, while at 95 deg C remained 4.39% and 11.60% of the initial activity, respectively, after 15 minutes. (author)

  1. Glutathione transferases are structural and functional outliers in the thioredoxin fold.

    Science.gov (United States)

    Atkinson, Holly J; Babbitt, Patricia C

    2009-11-24

    Glutathione transferases (GSTs) are ubiquitous scavengers of toxic compounds that fall, structurally and functionally, within the thioredoxin fold suprafamily. The fundamental catalytic capability of GSTs is catalysis of the nucleophilic addition or substitution of glutathione at electrophilic centers in a wide range of small electrophilic compounds. While specific GSTs have been studied in detail, little else is known about the structural and functional relationships between different groupings of GSTs. Through a global analysis of sequence and structural similarity, it was determined that variation in the binding of glutathione between the two major subgroups of cytosolic (soluble) GSTs results in a different mode of glutathione activation. Additionally, the convergent features of glutathione binding between cytosolic GSTs and mitochondrial GST kappa are described. The identification of these structural and functional themes helps to illuminate some of the fundamental contributions of the thioredoxin fold to catalysis in the GSTs and clarify how the thioredoxin fold can be modified to enable new functions.

  2. Modeling and Stability Assessment of Single-Phase Grid Synchronization Techniques

    DEFF Research Database (Denmark)

    Golestan, Saeed; Guerrero, Josep M.; Vasquez, Juan

    2018-01-01

    (GSTs) is of vital importance. This task is most often based on obtaining a linear time-invariant (LTI) model for the GST and applying standard stability tests to it. Another option is modeling and dynamics/stability assessment of GSTs in the linear time-periodic (LTP) framework, which has received...... a very little attention. In this letter, the procedure of deriving the LTP model for single-phase GSTs is first demonstrated. The accuracy of the LTP model in predicting the GST dynamic behavior and stability is then evaluated and compared with that of the LTI one. Two well-known single-phase GSTs, i...

  3. Molecular cloning, expression, and characterization of mouse amine N-sulfotransferases

    International Nuclear Information System (INIS)

    Takahashi, Saki; Sakakibara, Yoichi; Mishiro, Emi; Kouriki, Haruna; Nobe, Rika; Kurogi, Katsuhisa; Yasuda, Shin; Liu, M.-C.; Suiko, Masahito

    2008-01-01

    By searching the GenBank database, we recently identified a novel mouse cytosolic sulfotransferase (SULT) cDNA (IMAGE Clone ID 679629) and a novel mouse SULT gene (LOC 215895). Sequence analysis revealed that both mouse SULTs belong to the cytosolic SULT3 gene family. The recombinant form of these two newly identified SULTs, designated SULT3A1 and SULT3A2, were expressed using the pGEX-4T-1 glutathione S-transferase fusion system and purified from transformed BL21 Escherichia coli cells. Both purified SULT3A1 and SULT3A2 exhibited strong amine N-sulfonating activities toward 1-naphthylamine among a variety of endogenous and xenobiotic compounds tested as substrates. Kinetic constants of the sulfation of 1-naphthylamine and 1-naphthol by these two enzymes were determined. Collectively, these results imply that these two amine-sulfonating SULT3s may play essential roles in the metabolism and detoxification of aromatic amine compounds in the body

  4. Resistência de Bidens subalternans aos herbicidas inibidores da enzima acetolactato sintase utilizados na cultura da soja Resistance of Bidens subalternans to the acetolactate synthase inhibitor herbicides used in soybean crop

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    G.A. Gelmini

    2002-08-01

    Full Text Available O uso contínuo e prolongado de produtos com o mesmo mecanismo de ação pode provocar a manifestação de biótipos resistentes. Para verificar possíveis novos casos de resistência, bem como alternativas para prevenção e manejo, foram coletadas sementes de Bidens subalternans na região de São Gabriel D' Oeste-MS, em plantas que sobreviveram a tratamentos em que inibidores da ALS foram sistematicamente utilizados. Em experimento conduzido em vasos em casa de vegetação, o biótipo com histórico de resistente foi comparado ao suscetível quando submetido aos diversos herbicidas com diferentes mecanismos de ação usados em pós-emergência, os quais foram aplicados nas doses de zero, uma, duas, quatro e oito vezes a recomendada. Decorridos 20 dias, foram avaliadas a porcentagem de controle e a produção da fitomassa verde, visando estabelecimento de curvas de dose-resposta e obtenção dos fatores de resistência. O biótipo oriundo de área com histórico de aplicações repetidas de inibidores da ALS apresentou elevado nível de resistência aos herbicidas chlorimuron-ethyl e imazethapyr, demonstrando ser portador de resistência cruzada aos inibidores da ALS dos grupos das sulfoniluréias e imidazolinonas. Entretanto, esse biótipo foi eficientemente controlado pelos herbicidas fomesafen, lactofen, bentazon, glufosinato de amônio e glyphosate.The continuous and prolonged use of products with the same mechanism of action can provoke the manifestation of resistant biotypes. In horder to verify possible new cases, as well as alternatives for prevention and control, seeds of Bidens subalternans were collected at São Gabriel D' Oeste (MS region at plants that survived continuous treatments which sistematically ALS inhibitors. Through an experiment performed in pots inside a greenhouse, a resistant biotype was compared to a susceptible one when submitted to herbicides with different mechanisms of action and applied at post emergence. These herbicides were applied at doses zero, one, two, four and eight times the recommended dosage. Twenty days after, the control and the green weight production were analysed aiming to get the dose-response curves as well as the resistance factor. The biotype from the area with repeated application of ALS inhibitors showed a high level of resistance to chlorimuron-ethyl and imazethapyr, demonstrating therefore to be a carrier of crossed resistance to the ALS inhibitors of the sulfonilurea and imidazolinona groups. However, this biotype was controlled by fomesafen, lactofen, bentazon, ammonium glufosinate and glyphosate.

  5. Steatosis Hepática en Niños y Adolecentes obesos: Asociación con adiposidad, lípidos, insulina y enzimas hepática

    OpenAIRE

    Camacho, Nolis; Guillén, Mayela; Gil, Giobely 1; Paoli, Mariela; Molina, Zarela; Cicchetti, Rosanna; Molina, Yudisay; Parra, Isabel

    2010-01-01

    Objetivos: Estudiar la frecuencia de presentación de esteatosis hepática (EH) en un grupo de niños y adolescentes obesos y su asociación con medidas antropométricas, niveles de lípidos sanguíneos, resistencia a la insulina y aminotransferasas. Métodos: Se incluyeron 22 niños y adolescentes obesos (IMC>pc97) entre 6 y 13 años de edad, con promedio de 9,28 ± 1,9 años, 59% de sexo masculino y 41% femenino. Se tomaron tensión arterial y medidas antropométricas, incluyendo cintura, y se calcularon...

  6. Produção, purificação, clonagem e aplicação de enzimas líticas Production, purification, cloning and application of lytic enzymes

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    Luciana Francisco Fleuri

    2005-10-01

    Full Text Available Lytic enzymes such as beta-1,3 glucanases, proteases and chitinases are able to hydrolyse, respectively, beta-1,3 glucans, mannoproteins and chitin, as well as the cell walls of many yeast species. Lytic enzymes are useful in a great variety of applications including the preparation of protoplasts; the extraction of proteins, enzymes, pigments and functional carbohydrates; pre-treatment for the mechanical rupture of cells; degradation of residual yeast cell mass for the preparation of animal feed; analysis of the yeast cell wall structure and composition; study of the yeast cell wall synthesis and the control of pathogenic fungi. This review presents the most important aspects with respect to lytic enzymes, especially their production, purification, cloning and application.

  7. Tendencia de la tensión arterial en mujeres con hipertensión arterial esencial-estadio II tratadas con un inhibidor de la enzima convertidora de angiotensina

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    Mario E. Garcés Ferrer

    1995-10-01

    Full Text Available Hypertension stage II women were treated with quinapril (10mg/day an inhibitor of the angiotensin converting enzyme in order to follow blood pressure behavotr. Blood pressure was measured four times at nine week intervals. The mean blood pressure responses with time we significanthy lowered after the second control step.

  8. Avaliação da matriz nutricional da enzima fitase em rações contendo sorgo para poedeiras comerciais Evaluation of the nutritional matrix values for phytase enzyme in laying hens diets with sorghum

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    Elaine Cristina Ligeiro

    2009-10-01

    Full Text Available Avaliaram-se os efeitos da inclusão de fitase e de sua matriz nutricional em rações contendo sorgo sobre o desempenho das aves, a qualidade dos ovos, a ingestão e a excreção e retenção de fósforo e nitrogênio em poedeiras comerciais. Utilizaram-se 180 poedeiras comerciais, distribuídas em delineamento inteiramente ao acaso em esquema fatorial 2 × 2 + 1, com dois níveis de fitase (0 e 500 FTU/kg de ração e dois níveis de substituição do milho pelo sorgo (50 e 100% e uma ração testemunha (isenta de sorgo e fitase, constituindo cinco tratamentos com seis repetições de seis aves. As rações foram à base de milho e farelo de soja, sem fitase e sorgo, considerando a matriz nutricional da fitase. O desempenho e a qualidade dos ovos foram avaliados em quatro períodos de 28 dias. Ao final do experimento, um ensaio de metabolismo foi realizado para quantificar a ingestão, excreção e retenção aparente de fósforo e nitrogênio e avaliar a viabilidade econômica das rações. Ao considerar a matriz nutricional da fitase, as exigências em energia, cálcio, fósforo, proteína e aminoácidos foram atendidas, mesmo com a redução dos níveis nutricionais da dieta, e o desempenho e a qualidade dos ovos não foram comprometidos. A adição de fitase nas rações possibilitou reduzir todos os parâmetros econômicos avaliados. O sorgo pode substituir totalmente o milho e ser o único grão energético da dieta.The effects were assessed of including phytase and its nutritional matrix in diets containing sorghum on the performance of the birds, egg quality, intake and phosphorus excretion and retention in laying hens. One hundred and eighty laying hens were arranged in a randomized complete design in a 2 × 2 + 1 factorial arrangement with two phytase levels (0 and 500 FTU/kg diet, two levels of corn replacement for sorghum (50 and 100% and a control diet (without phytase and sorghum forming five treatments and six replications of six birds. The diets were based on corn and soybean meal, without phytase and sorghum, considering the phytase nutritional matrix. Performance and egg quality were determined in four 28-day periods. At the end of the experiment, a metabolism trial was carried out to quantify intake, excretion and apparent retention of phosphorus and nitrogen and to assess the economic viability of the diets. When the phytase nutritional matrix was considered, the energy, calcium phosphorus, protein and amino acid requirements were met, even with a reduction in the nutritional levels of the diet, and performance and egg quality were not affected. Adding phytase to the diets decreased all the economic parameters. Sorghum can be used to totally replace corn, and can be the only energy grain in the diet.

  9. Metabolismo del glutatión y enzimas antioxidantes frente al estrés por metal(oid)es y otros agentes, en el ciliado-modelo "Tetrahymena thermophila"

    OpenAIRE

    Ortega Herrero, Ruth

    2015-01-01

    El estrés oxidativo se define como el estado celular de desequilibrio entre moléculas oxidantes y antioxidantes. Esta definición se basa en la hipótesis Redox que se desarrolla en cuatro postulados: 1)Todo sistema vivo presenta elementos redox que son moléculas ricas en residuos de cisteína y que toman parte en los procesos de señalización celular, tráfico de macromoléculas y regulación fisiológica. 2)Estos elementos se coordinan mediante circuitos redox, que tienen nodos comunes como el gl...

  10. Avaliação fenotípica da enzima Klebsiella pneumoniae carbapenemase (KPC em Enterobacteriaceae de ambiente hospitalar Phenotypic research on Klebsiella pneumoniae carbapenemase (KPC enzyme in Enterobacteriaceae from hospitals

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    Rosabel Dienstmann

    2010-02-01

    Full Text Available INTRODUÇÃO E OBJETIVO: A resistência bacteriana é problema frequente e importante no ambiente nosocomial. Nesse contexto, várias bactérias apresentam habilidade de desenvolver mecanismos de resistência enzimáticos, destacando-se as Enterobacteriaceae. Nesta família de microrganismos, a produção de Klebsiella pneumoniae carbapenemase (KPC é um mecanismo emergente, o que justifica sua vigilância constante. MATERIAL E MÉTODO: Este trabalho pesquisou o fenótipo de KPC em 30 isolados clínicos de enterobactérias resistentes a cefalosporinas de terceira geração e sensibilidade diminuída a carbapenem oriundas de dois hospitais (em Porto Alegre e na Grande Porto Alegre, RS. Realizou-se discodifusão com imipenem, meropenem e ertapenem, e 14 cepas com halo INTRODUCTION AND OBJECTIVE: Bacterial resistance is a frequent and important problem in the nosocomial environment. In this context, several bacteria have the ability to develop mechanisms of enzymatic resistance, mainly Enterobacteriaceae. In this family of microorganisms, the production of Klebsiella pneumoniae carbapenemase (KPC is an emerging mechanism, which should be under constant observation. MATERIAL AND METHOD: This study investigated the phenotype of KPC in 30 clinical isolates of Enterobacteriaceae resistant to third generation cephalosporin and carbapenem from two hospitals (Porto Alegre city and Porto Alegre, RS. It was performed disk diffusion method with imipenem, meropenem and ertapenem. Additionally, 14 strains with halo < 22 mm for the last antimicrobial agent underwent modified Hodge test. RESULTS: No sample showed carbapenemase (Hodge negative. DISCUSSION: Despite the fact there was no carbapenemase, resistance to carbapenems is possibly attributed to the presence of beta-lactamases AmpC and/or ESBL associated with changes in the permeability of porin channels. CONCLUSION: Given the emerging nature of KPC, it is important to trace it in Enterobacteriaceae isolates with decreased susceptibility to ertapenem.

  11. Atividade de enzimas associadas ao estado de indução em mudas de cacaueiro expostas a dois actinomicetos residentes de filoplano Activity of enzymes associates of induced resistance on cocoa seedlings exposed of two actinomycetes phylloplane residents

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    Dirceu Macagnan

    2008-02-01

    Full Text Available Dois antagonistas selecionados para o biocontrole da vassoura-de-bruxa do cacaueiro foram avaliados quanto à capacidade em ativar mecanismos de defesa de plantas contra patógenos. Para tanto, mudas seminais de cacaueiro "comum" foram cultivadas em casa-de-vegetação por 30 dias e expostas aos antagonistas aplicados a mudas de cacaueiro por atomização, individualmente e em associação. O primeiro par de folhas das mudas dos diferentes tratamentos foi coletado aos dois, quatro, 12 e 24 dias após a exposição aos antagonistas. Foi quantificada a atividade de peroxidases, polifenoloxidases, quitinases e beta-1,3-glucanases no material coletado. Observou-se um aumento na atividade de peroxidases e polifenoloxidases nos primeiros dias após a exposição das mudas, especialmente ao isolado Ac26. Não foi observado efeito aditivo ou sinergístico nas mudas expostas aos dois isolados simultaneamente.Two antagonists selected for the biocontrol of cocoa witches' broom were investigated for their ability in triggering increases in the activity of enzymes associated to induced resistance. In a greenhouse, thirty days old cocoa seedlings were exposed t antagonists by spraying a propagule suspension of every antagonist or a mixture of them. At two, four 12 and 24 days exposing plants to the antagonists, the first leaf pair of every plant was excised and used for quantifying the activity of peroxidases, poly-phenol-oxidases, chitinases and beta-1,3-glucanases. There were increases in activity of peroxidases, poly-phenol-oxidases, mainly in the case of isolate Ac26. Additive or synergistic effects were not observed as a consequence of exposing plants to both antagonists together.

  12. Análisis de la sensibilidad de biotipos de Lolium multiflorum a herbicidas inhibidores de la enzima ALS, ACCasa y Glifosato Sensitivity analysis of Lolium multiflorum biotypes to Glyphosate, ACCase and ALS-inhibiting herbicides

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    P. Diez De Ulzurrun

    2012-09-01

    Full Text Available A pesar de los avances logrados en el control de las malezas con el uso de herbicidas, el manejo de las mismas no se simplificó, sino que, al contrario, surgieron nuevos desafíos, como la aparición de resistencia a herbicidas. En 2007, se reportó en Lolium multiflorum el segundo caso de resistencia a glifosato detectado en Argentina. En el sudeste de la provincia de Buenos Aires se registraron fallas de control a campo en poblaciones de Lolium multiflorum debido a su resistencia a distintos herbicidas de las familias de los inhibidores de ALS y de ACCasa y al herbicida glifosato. El objetivo de este estudio fue caracterizar el nivel de resistencia a ciertos herbicidas inhibidores de la ALS y de la ACCasa y al glifosato en una población de L. multiflorum de Lobería (Bs As, Argentina supuestamente resistente (LmR. Se realizaron bioensayos en cajas de Petri y se determinó la GR50 mediante la variación en la longitud de coleoptile. Las curvas de dosis-respuesta se obtuvieron por medio de la ecuación log-logística. El biotipo LmR presentó resistencia múltiple a herbicidas con tres modos de acción diferentes: glifosato, inhibidores de ALS y de ACCasa. Dicho ensayo demostró la aparición de un biotipo de L. multiflorum con resistencia a múltiples principios activos.Despite progress in weed control using herbicides, management has not been simplified, but new challenges such as herbicides resistance have arisen. In 2007, a Lolium multiflorum population resistant to glyphosate was reported, as the second case of glyphosate resistant weeds in Argentina. In the southeast of Buenos Aires province, control failures in populations of L. multiflorum to different families of herbicide such as ALS and ACCase inhibitors and to glyphosate at field level have been registered. The aim of this study was to characterize the level of resistance to certain herbicides inhibitors of ALS, ACCase and glyphosate in a putatively resistant (LmR population of L. multiflorum of Loberia (Buenos Aires, Argentina. Bioassays were conducted in Petri dishes and the GR50 was determined by the length of coleoptile. Curves dose-response were obtained using the log-logistic equation. The LmR biotype survived under multiple herbicides of three different modes of action, glyphosate, ALS and ACCase inhibitors. This test showed the appearance of a biotype of L. multiflorum with resistance to multiple active ingredients.

  13. Enzimas miocárdicas na cirurgia de revascularização sem circulação extracorpórea Myocardial enzymes in off-pump CABG surgery

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    Paulo Roberto SOLTOSKI

    2000-06-01

    Full Text Available INTRODUÇÃO: A cirurgia cardíaca com o coração batendo está sendo cada vez mais utilizada para minimizar danos cerebrais, renais e outros. Porém, a incidência de infarto nos períodos per e pós-operatório e seu efeito a longo prazo, especialmente quando esta técnica é comparada às tradicionais, ainda não foi totalmente esclarecida. CASUÍSTICA E MÉTODOS: Um estudo retrospectivo de 303 pacientes (122 sem CEC, 181 com CEC foi realizado de fevereiro/97 a fevereiro/99. Dosagens de CK-MB e eletrocardiogramas foram avaliados nos períodos per e pós-operatório, troponina T (TnT foi medida no período pós-operatório. Os dois grupos foram comparáveis quanto a idade (65 ± 10 anos vs. 65 ± 9 anos, classificações CCS e NYHA. RESULTADOS: O número médio de enxertos com CEC foi de 3,10 vs. 2,26 sem CE. Infarto peri-operatório, assim como morbidade e mortalidade (7/181 vs. 6/122 foram comparáveis. Apesar de mais elevados no grupo com CEC, os níveis pós-operatórios de CK-MB e troponina T não atingiram diferença estatística, tendo sido observados 21 infartos agudos por critérios bioquímicos que se distribuíram igualmente entre os grupos. Uma correlação inversa entre o número de enxertos e a liberação de troponina foi observada na fase inicial da nossa experiência sem CEC. Não houve relação entre a localização do enxerto e a incidência de infarto ou liberação de troponina. CONCLUSÃO: A proteção miocárdica, morbidade e mortalidade obtidas com as duas técnicas de revascularização estudadas foram semelhantes. Considerando os efeitos adversos da CEC, já documentados na literatura, particularmente sobre os sistemas neurológico, respiratório e renal sugerimos esta técnica como uma alternativa segura para a revascularização miocárdica.BACKGROUND: CABG surgery on the beating heart (off-pump is increasingly used to lessen injury to the brain, kidneys and other organs. However, the perioperative incidence of myocardial injury and its effect on outcome vs conventional CABG (on-pump remains unclear. MATERIAL AND METHODS: Retrospective study of 303 patients (122 off-pump, 181 on-pump after isolated CABG from Feb/97-Feb/99. CPK and EKG were obtained pre and post-op, MB fraction and troponin T levels were measured postoperatively. Complications were also recorded. The groups were comparable in terms of age (65 ± 10 vs 65 ± 9 yr, CCS and NYHA class. RESULTS: Mean number of grafts was 3.10 on-pump vs 2.26 off-pump. Perioperative myocardial infarction, morbidity and mortality (7/181 vs 6/122 were also comparable. There were higher postoperative CK levels in the on-pump group compared to the off-pump (548 ± 420 vs 236 ± 365. MB fraction was slightly higher in the on-pump group, but not significantly different (62 ± 197 vs 29 ± 46 nor was troponin T levels (3.5 ± 16 vs 3.5 ± 17 were An inverse correlation between the number of grafts and troponin T release in the off-pump group occurred early during our off-pump experience. There was no correlation between graft location and the incidence of infarcts or troponin T release. CONCLUSION: The higher troponin T release during our initial experience subsequently decreased. This suggests that improvements in operative technique (e.g. better exposure allowing more posterior grafts without surface trauma may be responsible. Current techniques make off-pump CABG a safe alternative for revascularization.

  14. Atividade da enzima acetil-hidrolase do fator ativador de plaquetas (PAF-AH em pacientes com diabete melito tipo 1 Platelet-activating factor acetylhydrolase (PAF-AH activity in patients with type 1 diabetes mellitus

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    Simone Henriques de Castro

    2007-02-01

    Full Text Available OBJETIVO: Avaliar a atividade da acetil-hidrolase do fator ativador de plaquetas (PAF-AH e sua relação com variáveis clinicodemográficas, com o controle metabólico, os níveis de apolipoproteínas A e B e a suscetibilidade da lipoproteína de baixa densidade (LDL à oxidação in vitro em pacientes com DM tipo 1 (DM 1. MÉTODOS: Foram avaliados 42 pacientes com DM1 (27 mulheres e 48 não-diabéticos (16 mulheres, pareados por sexo, idade e índice de massa corporal (IMC. Os exames realizados foram: glicemia de jejum (GJ e pós-prandial (GPP, lipidograma, ácido úrico (AU, hemoglobina glicosilada (HbA1c e coeficiente de oxidação da lipoproteína de baixa densidade (LDL por espectrofotometria. A análise da atividade da PAF-AH foi realizada por espectrofotometria (Cayman Chemical. RESULTADOS: A análise da atividade da PAF-AH mostrou haver maior atividade enzimática nos pacientes com DM 1 do que nos não-diabéticos (0,0150 ± 0,0051 versus 0,0116 ± 0,0041; p OBJECTIVE: To evaluate platelet-activating factor acetylhydrolase (PAF-AH activity and its relationship with clinical and demographic variables, metabolic control, apolipoprotein A and B levels and the susceptibility of low-density lipoprotein (LDL to in vitro oxidation in patients with type 1 diabetes mellitus (DM 1. METHODS: Forty two patients with DM 1 (27 females and 48 control subjects (16 females matched for gender, age and body mass index (BMI were evaluated. The following tests were performed: fast plasma glucose (FG and postprandial plasma glucose (PPG, lipid profile, uric acid (UA, glycosylated hemoglobin (HbA1c, and low-density lipoprotein (LDL oxidation rate using colorimetric assay. The PAF-AH activity was analyzed using colorimetric assay (Cayman Chemical. RESULTS: The analysis of PAF-AH activity showed a higher enzyme activity in patients with DM 1 than in control subjects (0.0150 ± 0.0051 vs. 0.0116 ± 0.0041; p < 0.001. In patients with DM 1, a direct correlation between PAF-AH activity and age and LDL, and an inverse correlation between PAF-AH and HbA1c and high-density lipoprotein (HDL were found. CONCLUSION: In the sample studied, PAF-AH showed a higher activity in patients with DM 1, a factor that may be related to the higher risk of developing cardiovascular diseases observed in these patients. Further studies are necessary to evaluate the real participation of this enzyme in the risk of development of atherosclerotic diseases in patients with DM 1.

  15. UTILIDAD DEL BANDEO CROMOSÓMICO CON LA ENZIMA Alu I PARA LA IDENTIFICACIÓN DE ZONAS METILADAS EN LEUCEMIAS AGUDAS I UTILITY OF CHROMOSOME BANDING WITH Alu I ENZYME FOR IDENTIFYING METHYLATED AREAS IN ACUTE LEUKEMIAS

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    Maribel Quintero

    2018-04-01

    Full Text Available Acute leukemias are malignant hematopoietic cells of immature proliferations of the blastic type, whose progressive accumulation is accompanied by a decrease in the production of normal myeloid elements. Transcription of inactive tumor suppressor genes by hypermethylation of CpG islands in promoter regions, has been a focus of researchers as a causal factor in hematological malignancies. The purpose of this study was to determine hypermethylated regions of chromosomal spread samples using Alu I and relate these regions with sites of suppressor gene associated to acute leukemia tumors. From an analysis of a 30 bone marrow samples, 18 were diagnosed with Acute Myeloid Leukemia and Acute Lymphoid Leukemia, and 12 underwent cell culture. Chromosomal spreads were stained with Giemsa after being previously digested with the enzyme Alu I. In patients with acute myeloid leukemia and acute lymphoid leukemia it was observed that 16/18 (88% and 12/12 (100% had abnormally stained regions, single in four and three methylated regions observed in acute myeloid leukemia and acute lymphoid leukemia, respectively, no association was found in the literature with methylated genes, which was highly significant ( p < 0.01 in both conditions. This shows the usefulness of this technique for the identification of methylated areas, since they have provided the foundation and the molecular basis for a better targeted therapeutic approach with demethylating agents, both in acute leukemias and myelodysplastic syndromes.

  16. Inmovilización de la enzima Lactozym en soportes mesoporosos (MCM-41) y su aplicación en la obtención de leches bajas en lactosa

    OpenAIRE

    Usuriaga Mulato, Yeniffer

    2015-01-01

    Trabajo de grado, presentado como requisito parcial para optar al título de Químico por la Universidad del Cauca, Facultad de Ciencias Naturales, Exactas y de la Educación, Departamento de Química.

  17. INTERAÇÕES FÁRMACO-RECEPTOR: APLICAÇÕES DE TÉCNICAS COMPUTACIONAIS EM AULA PRÁTICA SOBRE A EVOLUÇÃO DOS INIBIDORES DA ENZIMA CONVERSORA DE ANGIOTENSINA

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    Maurício Temotheo Tavares

    2015-09-01

    Full Text Available Teaching classes and events regarding the molecular aspects of drug-receptor interactions is not an easy task. The ligand stereochemistry and the spatial arrangement of the macromolecular targets highly increase the complexity of the process. In this context, the use of alternative and more playful approaches could allow students to gain a more thorough understanding of this important topic in medicinal chemistry. Herein, we describe a practical teaching approach that uses computational strategies as a tool for drug-receptor interaction studies performed for angiotencsin converting enzyme inhibitors (ACEi. Firstly, the students learn how to find the crystallographic structure (enzyme-ligand complex. Then, they proceed to the treatment of crude crystallographic data. Thereafter, they learn how to analyze the positioning of the drug on the active site of the enzyme, looking for regions related to the molecular recognition. At the end of the study, students can summarize the molecular requirements for the interaction and the structure-activity relationships of the studied drugs.

  18. Análisis de iridoides y expresión de genes que codifican enzimas tempranas en la síntesis de alcaloides indol terpenoicos en catharanthus roseus

    OpenAIRE

    Palacios-Rojas, Natalia; Leech, Mark

    2007-01-01

    Los alcaloides indol terpenoicos (TIA) son metabolitos secundarios de importancia medicinal por sus propiedades como agentes anticancerígenos, entre otras. Sin embargo, su explotación en la industria farmacéutica se ha visto limitada, ya que la acumulación de estos compuestos en las plantas que los producen es mínima. Dichos alcaloides son biosintetizados por la vía del shikimato y de los terpenoides, los cuales proveen los precursores: secologanina y triptamina, respectivamente. La secologan...

  19. Evaluación de métodos de extracción y purificación de enzimas pectinolíticas obtenidas por fermentación en estado semisólido del Aspergillus niger

    OpenAIRE

    Rojas Muñoz, Víctor René

    2009-01-01

    El presente estudio se llevó a cabo para evaluar diferentes métodos de bioseparación orientados a la recuperación de exopoligalacturonasas (exo-PG) y endopoligalacturonasas (endo-PG) contenidas en el extracto enzimático procedente de la fermentación en medio semisólido de Aspergillus niger utilizando cáscara de naranja para la preparación de los sustratos.

  20. Exercício físico promove efeito antioxidante e restaura a expressão das enzimas óxido nítrico sintases no bulbo ventrolateral rostral de ratos com hipertensão renovascular.

    OpenAIRE

    Souza, Luiz Eduardo de

    2015-01-01

    Programa de Pós-Graduação em Ciências Biológicas. Núcleo de Pesquisas em Ciências Biológicas, Pró-Reitoria de Pesquisa de Pós Graduação, Universidade Federal de Ouro Preto. O exercício físico tem importante ação no sistema nervoso e órgãos reguladores da pressão arterial. Objetivos: Verificar o efeito do exercício físico sobre a expressão das óxido nítrico sintases (NOSs) no bulbo ventrolateral rostral (RVLM) e estado redox no encéfalo, coração, rins e aorta de ratos com hipertensão re...

  1. Avaliação da capacidade de produção de biofilmes e detecção da enzima KPC em Salmonella spp. isoladas de aviário e linha de abate de aves

    OpenAIRE

    Míriam Gonçalves Marquezini

    2015-01-01

    De acordo com a Food and Agriculture Organization of the United Nations (FAO, 2013), o consumo mundial de carne de frango tem aumentado de maneira significativa nas últimas décadas. Por outro lado, a preocupação dos produtores de alimentos, com a inocuidade de seus produtos também tem aumentado na mesma proporção. Durante as etapas da operação de abate de maneira geral, as contaminações cruzadas são as principais causas de disseminação de microrganismos patogênicos nos produtos obtidos e caus...

  2. Sistema em fluxo para determinação espectrofotométrica de uréia em plasma de sangue animal empregando leguminosa como fonte natural da enzima urease

    Directory of Open Access Journals (Sweden)

    Luca Gilmara C.

    2001-01-01

    Full Text Available A spectrophotometric flow injection analysis (FIA procedure employing natural urease enzyme source for the determination of urea in animal blood plasma was developed. Among leguminous plants used in the Brazilian agriculture, the Cajanus cajan specie was selected as urease source considering its efficiency and availability. A minicolumn was filled with leguminous fragments and coupled to the FIA manifold, where urea was on-line converted to ammonium ions and subsequently it was quantified by spectrophotometry. The system was employed to determine urea in animal plasma samples without any prior treatment. Accuracy was assessed by comparison results with those obtained employing the official procedure and no significant difference at 90 % confidence level was observed. Other profitable features such as an analytical throughput of 30 determinations per hour, a reagent consumption of 19.2 mg sodium salicylate, 0.5 mg sodium hipochloride and a relative standard deviation of 1.4 % (n= 12 were also obtained.

  3. Papel da enzima óxido nítrico sintase induzível no desenvolvimento da hipertrofia e disfunção cardíaca /

    OpenAIRE

    Dias, Fernando Augusto Lavezzo

    2007-01-01

    Orientador : Rosalvo T.H. Fogaça Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa: Curitiba, 2007 Inclui bibliografia Área de concentração : Fisiologia

  4. Modulation of antioxidant enzymes as radioprotector mechanism of oligo elements and lachesis muta in normal tissues; Modulacion de enzimas antioxidantes como mecanismo radioprotector de oligoelementos y lachesis muta en tejidos normales

    Energy Technology Data Exchange (ETDEWEB)

    Crescenti, E.; Croci, M. [Instituto de Inmunooncologia, Cordoba 3200, Buenos Aires (Argentina); Mohamad, N.; Medina, V.; Sambuco, L.; Gutierrez, A.; Nunez, M.; Martin, G.; Cricco, G.; Bergoc, R.; Rivera, E. [Laboratorio de Radioisotopos, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires. Junin 956. Buenos Aires, (Argentina)]. e-mail: crescentilab@fibertel.com.ar

    2006-07-01

    The therapeutic use of the ionizing radiations (IR) it has acquired great relevance in the last decades although their effects are not selective and they are also manifested on the normal tissues. In previous works we demonstrate the radioprotector effect that the combination of oligo elements Zinc, Selenium and Manganese associated to the snake poison Lachesis muta (O-LM) it exercises on the small intestine and the bone marrow of irradiated mouse. The objective of this work was to study the molecular mechanisms, and particularly the paper of the anti-oxidant superoxide dismutases enzymes (MnSOD and Cu/ZnSOD), Catalase (CAT), and Glutathione Peroxidase (GPx), in the radioprotector action that exercises the combination O-LM. Four groups of mice were used: A) control; B) treated with O-LM; C) irradiated; D) irradiated and treated with O-LM. The two treated groups were injected daily via s.c. with 0,1 ml of O-LM from 30 days before the irradiation and until to 4 days later. The two irradiated groups received 10 Gy in whole body the day 30. The day 35 all the animals were sacrificed. The histological intestinal cuts of the mucous one were evaluated by tint with hematoxyline-eosin; the presence of apoptotic cells it was determined by the Tunel method (Apoptag kit); the expression of PCNA (nuclear antigen of proliferating cells), MnSOD, CuZnSOD, CAT and GPx, by immunohistochemistry. The results demonstrated that in the lot D it was preserved totally the histology of the intestinal mucous. In the control A it was observed PCNA expression in the crypts, of MnSOD in the hairiness and CuZnSOD, CAT and Gpx in both. The change produced by O-LM (group B) it was the increase of PCNA, of CAT and the appearance of MnSOD in the crypts. On the other hand, the irradiation (C) it produced a marked descent in the GPx, the complete disappearance of PCNA and an increase of the apoptotic cells. The group D showed that O-LM it reverted totally the effect of the RI on the expression of PCNA, diminished the number of apoptotic cells and increase the CAT expression and CuZnSOD in hairiness and crypts. We conclude that the treatment with O-LM it modulates the expression of anti-oxidant enzymes, the expression of PCNA increases and it inhibits the apoptosis. This way the treatment with O-LM increases the proliferation and the anti-oxidant capacity of the intestinal mucous one, accelerating the damage repair and exercising by this way an effective radioprotector effect. These results endorse the potential use of O-LM in patients subjected to radiant therapy. (Author)

  5. Efecto del entrenamiento físico sobre la mitocondriogénesis y la expresión de enzimas antioxidantes en el músculo de animales jóvenes, viejos y knockout de PGC-1 ALPHA

    OpenAIRE

    Nascimento, Ana Lucia

    2010-01-01

    El envejecimiento humano está asociado a una pérdida de masa muscular que se inicia en la cuarta década de la vida con una pérdida de fuerza de un 1% al año y que se acelera con el transcurso de los años. Las causas del envejecimiento del organismo son complejas. Una amplia variedad de procesos se considera que están implicados en el declive de los distintos aparatos y sistemas con el paso de los años. Dentro los factores implicados en la pérdida de la funcionalidad del músc...

  6. Proteção funcional da enzima heme-oxigenase-1 na lesão renal aguda isquêmica e tóxica Protección funcional de la enzima heme-oxigenasa-1 en la lesión renal aguda isquémica y tóxica Functional protection of heme-oxygenase-1 enzyme in ischemic and toxic acute kidney injury

    Directory of Open Access Journals (Sweden)

    Cassiane Dezoti

    2009-01-01

    Full Text Available OBJETIVOS: Verificar a proteção funcional da heme-oxigenase (HO-1, por meio do uso do seu indutor (Hemin e seu inibidor químico (protoporfirina de zinco-ZnPP na lesão renal aguda isquêmica e tóxica pela Polimixina B (PmxB em ratos. MATERIAL: Foram utilizados ratos Wistar, adultos e machos divididos em 8 grupos: SHAM (controle, Isquemia (Isq, Isq+Hemin (indutor de HO-1, Isq+ZnPP (inibidor de HO-1, SALINA (controle, Polimixina B (PmxB, PmxB+Hemin, PmxB+ZnPP. MÉTODOS: Jaffé (clearance de creatinina, Clcr e FOX-2 (peróxidos urinários. RESULTADOS: A isquemia (30´ dos pedículos reais e a administração de PmxB reduziu o Clcr com manutenção do fluxo urinário. Os peróxidos urinários se elevaram em ambas as lesões. A administração do Indutor de HO-1 determinou melhora da função renal e redução dos níveis de peróxidos urinários. CONCLUSÃO: Os resultados deste estudo demonstraram que a isquemia e a PmxB induzem LRA oxidativa. O indutor de HO-1 atenuou a lesão em ambos os modelos por atenuação do mecanismo redox.OBJETIVOS: Verificar la protección funcional de la heme-oxigenasa (HO-1, por medio del uso de su inductor (Hemin y su inhibidor químico (protoporfirina de zinc-ZnPP en la lesión renal aguda isquémica y tóxica producida por la Polimixina B (PmxB en ratas. MATERIAL: Fueron utilizadas ratas Wistar, adultas y machos divididos en 8 grupos: SHAM (control, Isquemia (Isq, Isq+Hemin (indutor de HO-1, Isq+ZnPP (inibidor de HO-1, SALINA (control, Polimixina B (PmxB, PmxB+Hemin, PmxB+ZnPP. MÉTODOS: Jaffé (clearance de creatinina, Clcr y FOX-2 (peróxidos urinarios. RESULTADOS: La isquemia (30´ de los pedículos reales y la administración de PmxB redujo el Clcr con manutención del flujo urinario. Los peróxidos urinarios se elevaron en ambas lesiones. La administración del Inductor de HO-1 determinó mejora de la función renal y reducción de los niveles de peróxidos urinarios. CONCLUSIÓN: Los resultados de este estudio demuestran que la isquemia y la PmxB inducen AKL por la elevación de los peróxidos urinarios. El inductor de HO-1 atenuó la lesión en ambos modelos por atenuación del mecanismo redox.OBJECTIVE: To investigate the functional protection of heme-oxygenase-1 enzyme (HO-1 when using its inducer (Hemin and inhibitor (zinc protoporphyrin-ZnPP in ischemic and toxic acute kidney injury by Polymixin B in mice. MATERIALS: Adult male Wistar mice divided into 8 groups were used: SHAM (control, Ischemic (Isq, Isq+Hemin (Inducer of H0-1, Isq+ZnPP (inhibitor of H0-1, SALINA (control, Polimyxin B (PmxB, PmxB+Hemin, PmxB+ZnPP. METHOD: Analysis consists of Jaffé (creatinine clearance [crCl] and FOX-2 (urinary peroxides [UP]. RESULTS: Thirty minutes renal ischemia and its treatment with PmxB reduced the crCl and maintained urinary output. Urinary peroxide levels increased in both injuries. The administration of the inducer of H0-1 resulted in improvement in renal function and reduction in the levels of urinary peroxide. CONCLUSIONS: Findings indicated that ischemia and PmxB induce LAR (acute kidney injury [AKI] by elevating the levels of urinary peroxide. The HO-1 inducer ameliorated the injury in both animal models through redox mechanism.

  7. Stress-inducible GmGSTU4 shapes transgenic tobacco plants metabolome towards increased salinity tolerance

    NARCIS (Netherlands)

    Kissoudis, Christos; Kalloniati, Chrissanthi; Flemetakis, Emmanouil; Madesis, Panagiotis; Labrou, Nikolaos E.; Tsaftaris, Athanasios; Nianiou-Obeidat, Irini

    2015-01-01

    The involvement of glutathione transferases (GSTs) in plant’s tolerance to abiotic stresses has been extensively studied; however, the metabolic changes occurring in the plants with altered GSTs expression have not been studied in detail. We have previously demonstrated that GmGSTU4

  8. Quantum Mechanical/Molecular Mechanical Free Energy Simulations of the Glutathione S-Transferase (M1-1) Reaction with Phenanthrene 9,10-Oxide

    NARCIS (Netherlands)

    Ridder, L.; Rietjens, I.M.C.M.; Vervoort, J.J.M.; Mulholland, A.J.

    2002-01-01

    Glutathione S-transferases (GSTs) play an important role in the detoxification of xenobiotics in mammals. They catalyze the conjugation of glutathione to a wide range of electrophilic compounds. Phenanthrene 9,10-oxide is a model substrate for GSTs, representing an important group of epoxide

  9. Geospatial Technology in Geography Education

    NARCIS (Netherlands)

    Muniz Solari, Osvaldo; Demirci, A.; van der Schee, J.A.

    2015-01-01

    The book is presented as an important starting point for new research in Geography Education (GE) related to the use and application of geospatial technologies (GSTs). For this purpose, the selection of topics was based on central ideas to GE in its relationship with GSTs. The process of geospatial

  10. GST Theta null genotype is associated with an increased risk for ulcerative colitis: a case-control study and meta-analysis of GST Mu and GST Theta polymorphisms in inflammatory bowel disease

    NARCIS (Netherlands)

    Broekman, M.M.T.J.; Bos, C.; Morsche, R.H.M. te; Hoentjen, F.; Roelofs, H.M.J.; Peters, W.H.M.; Wanten, G.J.A.; Jong, D.J. de

    2014-01-01

    Glutathione S-transferases (GSTs) are important in the detoxification of many compounds, including reactive oxygen species. Polymorphisms in GSTs resulting in a decreased enzyme activity might enhance the risk for inflammatory bowel disease by eliciting a state of oxidative stress. Previous

  11. Inhibition of rat, mouse, and human glutathione S-transferase by eugenol and its oxidation products

    NARCIS (Netherlands)

    Rompelberg, C.J.M.; Ploemen, J.H.T.M.; Jespersen, S.; Greef, J. van der; Verhagen, H.; Bladeren, P.J. van

    1996-01-01

    The irreversible and reversible inhibition of glutathione S-transferases (GSTs) by eugenol was studied in rat, mouse and man. Using liver cytosol of human, rat and mouse, species differences were found in the rate of irreversible inhibition of GSTs by eugenol in the presence of the enzyme

  12. Characterization of glutathione transferases involved in the pathogenicity of Alternaria brassicicola.

    Science.gov (United States)

    Calmes, Benoit; Morel-Rouhier, Mélanie; Bataillé-Simoneau, Nelly; Gelhaye, Eric; Guillemette, Thomas; Simoneau, Philippe

    2015-06-18

    Glutathione transferases (GSTs) represent an extended family of multifunctional proteins involved in detoxification processes and tolerance to oxidative stress. We thus anticipated that some GSTs could play an essential role in the protection of fungal necrotrophs against plant-derived toxic metabolites and reactive oxygen species that accumulate at the host-pathogen interface during infection. Mining the genome of the necrotrophic Brassica pathogen Alternaria brassicicola for glutathione transferase revealed 23 sequences, 17 of which could be clustered into the main classes previously defined for fungal GSTs and six were 'orphans'. Five isothiocyanate-inducible GSTs from five different classes were more thoroughly investigated. Analysis of their catalytic properties revealed that two GSTs, belonging to the GSTFuA and GTT1 classes, exhibited GSH transferase activity with isothiocyanates (ITC) and peroxidase activity with cumene hydroperoxide, respectively. Mutant deficient for these two GSTs were however neither more susceptible to ITC nor less aggressive than the wild-type parental strain. By contrast mutants deficient for two other GSTs, belonging to the Ure2pB and GSTO classes, were distinguished by their hyper-susceptibility to ITC and low aggressiveness against Brassica oleracea. In particular AbGSTO1 could participate in cell tolerance to ITC due to its glutathione-dependent thioltransferase activity. The fifth ITC-inducible GST belonged to the MAPEG class and although it was not possible to produce the soluble active form of this protein in a bacterial expression system, the corresponding deficient mutant failed to develop normal symptoms on host plant tissues. Among the five ITC-inducible GSTs analyzed in this study, three were found essential for full aggressiveness of A. brassicicola on host plant. This, to our knowledge is the first evidence that GSTs might be essential virulence factors for fungal necrotrophs.

  13. Glutathione transferase supergene family in tomato: Salt stress-regulated expression of representative genes from distinct GST classes in plants primed with salicylic acid.

    Science.gov (United States)

    Csiszár, Jolán; Horváth, Edit; Váry, Zsolt; Gallé, Ágnes; Bela, Krisztina; Brunner, Szilvia; Tari, Irma

    2014-05-01

    A family tree of the multifunctional proteins, glutathione transferases (GSTs, EC 2.5.1.18) was created in Solanum lycopersicum based on homology to known Arabidopsis GSTs. The involvement of selected SlGSTs was studied in salt stress response of tomato primed with salicylic acid (SA) or in un-primed plants by real-time qPCR. Selected tau GSTs (SlGSTU23, SlGSTU26) were up-regulated in the leaves, while GSTs from lambda, theta, dehydroascorbate reductase and zeta classes (SlGSTL3, SlGSTT2, SlDHAR5, SlGSTZ2) in the root tissues under salt stress. Priming with SA exhibited a concentration dependency; SA mitigated the salt stress injury and caused characteristic changes in the expression pattern of SlGSTs only at 10(-4) M concentration. SlGSTF4 displayed a significant up-regulation in the leaves, while the abundance of SlGSTL3, SlGSTT2 and SlGSTZ2 transcripts were enhanced in the roots of plants primed with high SA concentration. Unexpectedly, under high salinity the SlDHAR2 expression decreased in primed roots as compared to the salt-stressed plants, however, the up-regulation of SlDHAR5 isoenzyme contributed to the maintenance of DHAR activity in roots primed with high SA. The members of lambda, theta and zeta class GSTs have a specific role in salt stress acclimation of tomato, while SlGSTU26 and SlGSTF4, the enzymes with high glutathione conjugating activity, characterize a successful priming in both roots and leaves. In contrast to low concentration, high SA concentration induced those GSTs in primed roots, which were up-regulated under salt stress. Our data indicate that induction of GSTs provide a flexible tool in maintaining redox homeostasis during unfavourable conditions. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  14. On the sulfation of O-desmethyltramadol by human cytosolic sulfotransferases.

    Science.gov (United States)

    Rasool, Mohammed I; Bairam, Ahsan F; Kurogi, Katsuhisa; Liu, Ming-Cheh

    2017-10-01

    Previous studies have demonstrated that sulfate conjugation is involved in the metabolism of the active metabolite of tramadol, O-desmethyltramadol (O-DMT). The current study aimed to systematically identify the human cytosolic sulfotransferases (SULTs) that are capable of mediating the sulfation of O-DMT. The sulfation of O-DMT under metabolic conditions was demonstrated using HepG2 hepatoma cells and Caco-2 human colon carcinoma cells. O-DMT-sulfating activity of thirteen known human SULTs and four human organ specimens was examined using an established sulfotransferase assay. pH-Dependency and kinetic parameters were also analyzed using, respectively, buffers at different pHs and varying O-DMT concentrations in the assays. Of the thirteen human SULTs tested, only SULT1A3 and SULT1C4 were found to display O-DMT-sulfating activity, with different pH-dependency profiles. Kinetic analysis revealed that SULT1C4 was 60 times more catalytically efficient in mediating the sulfation of O-DMT than SULT1A3 at respective optimal pH. Of the four human organ specimens tested, the cytosol prepared from the small intestine showed much higher O-DMT-sulfating activity than cytosols prepared from liver, lung, and kidney. Both cultured HepG2 and Caco-2 cells were shown to be capable of sulfating O-DMT and releasing sulfated O-DMT into cultured media. SULT1A3 and SULT1C4 were the major SULTs responsible for the sulfation of O-DMT. Collectively, the results obtained provided a molecular basis underlying the sulfation of O-DMT and contributed to a better understanding about the pharmacokinetics and pharmacodynamics of tramadol in humans. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  15. Molecular characterization of zeta class glutathione S-transferases ...

    Indian Academy of Sciences (India)

    In higher plants, studies on GSTs have focussed largely on agricultural plants. There is ... Mediterranean region and have to cope with several environmental stress conditions. ..... Naliwajski M. R. and Skłodowska M 2014 The oxidative stress.

  16. Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

    OpenAIRE

    Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

    2002-01-01

    A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction tha...

  17. UDP-glucuronosyltransferase and sulfotransferase polymorphisms, sex hormone concentrations, and tumor receptor status in breast cancer patients

    International Nuclear Information System (INIS)

    Sparks, Rachel; Yuan, Xiaopu; Lin, Ming Gang; McVarish, Lynda; Aiello, Erin J; McTiernan, Anne; Ulrich, Cornelia M; Bigler, Jeannette; Tworoger, Shelley S; Yasui, Yutaka; Rajan, Kumar B; Porter, Peggy; Stanczyk, Frank Z; Ballard-Barbash, Rachel

    2004-01-01

    UDP-glucuronosyltransferase (UGT) and sulfotransferase (SULT) enzymes are involved in removing sex hormones from circulation. Polymorphic variation in five UGT and SULT genes – UGT1A1 ((TA) 6 /(TA) 7 ), UGT2B4 (Asp 458 Glu), UGT2B7 (His 268 Tyr), UGT2B15 (Asp 85 Tyr), and SULT1A1 (Arg 213 His) – may be associated with circulating sex hormone concentrations, or the risk of an estrogen receptor-negative (ER - ) or progesterone receptor-negative (PR - ) tumor. Logistic regression analysis was used to estimate the odds ratios of an ER - or PR - tumor associated with polymorphisms in the genes listed above for 163 breast cancer patients from a population-based cohort study of women in western Washington. Adjusted geometric mean estradiol, estrone, and testosterone concentrations were calculated within each UGT and SULT genotype for a subpopulation of postmenopausal breast cancer patients not on hormone therapy 2–3 years after diagnosis (n = 89). The variant allele of UGT1A1 was associated with reduced risk of an ER - tumor (P for trend = 0.03), and variants of UGT2B15 and SULT1A1 were associated with non-statistically significant risk reductions. There was some indication that plasma estradiol and testosterone concentrations varied by UGT2B15 and SULT1A1 genotypes; women with the UGT2B15 Asp/Tyr and Tyr/Tyr genotypes had higher concentrations of estradiol than women with the Asp/Asp genotype (P = 0.004). Compared with women with the SULT1A1 Arg/Arg and Arg/His genotypes, women with the His/His genotype had elevated concentrations of testosterone (P = 0.003). The risk of ER - breast cancer tumors may vary by UGT or SULT genotype. Further, plasma estradiol and testosterone concentrations in breast cancer patients may differ depending on some UGT and SULT genotypes

  18. The stereoselective sulfate conjugation of 4'-methoxyfenoterol stereoisomers by sulfotransferase enzymes.

    Science.gov (United States)

    Iyer, Lalitha V; Ramamoorthy, Anuradha; Rutkowska, Ewelina; Furimsky, Anna M; Tang, Liang; Catz, Paul; Green, Carol E; Jozwiak, Krzysztof; Wainer, Irving W

    2012-10-01

    The presystemic sulfate conjugation of the stereoisomers of 4'-methoxyfenoterol, (R,R')-MF, (S,S')-MF, (R,S')-MF, and (S,R')-MF, was investigated using commercially available human intestinal S9 fractions, a mixture of sulfotransferase (SULT) enzymes. The results indicate that the sulfation was stereospecific and that an S-configuration at the β-OH carbon of the MF molecule enhanced the maximal formation rates with (S,R')-MF  (S,S')-MF  (R,S')-MF ≈ (R,R')-MF, and competition studies demonstrated that (S,R')-MF is an effective inhibitor of (R,R')-MF sulfation (IC(50) = 60 μM). In addition, the results from a cDNA-expressed human SULT isoform screen indicated that SULT1A1, SULT1A3, and SULT1E1 can mediate the sulfation of all four MF stereoisomers. Previously published molecular models of SULT1A3 and SULT1A1 were used in docking simulations of the MF stereoisomers using Molegro Virtual Docker. The models of the MF-SULT1A3 and MF-SULT1A1 complexes indicate that each of the two chiral centers of MF molecule plays a role in the observed relative stabilities. The observed stereoselectivity is the result of multiple hydrogen bonding interactions and induced conformational changes within the substrate-enzyme complex. In conclusion, the results suggest that a formulation developed from a mixture of (R,R')-MF and (S,R')-MF may increase the oral bioavailability of (R,R')-MF. Copyright © 2012 Wiley Periodicals, Inc.

  19. Identification, characterization and expression profiles of Chironomus riparius glutathione S-transferase (GST) genes in response to cadmium and silver nanoparticles exposure

    Energy Technology Data Exchange (ETDEWEB)

    Nair, Prakash M. Gopalakrishnan [School of Environmental Engineering and Graduate School of Energy and Environmental System Engineering, University of Seoul, 90 Jeonnong-dong, Dongdaemun-gu, Seoul 130-743 (Korea, Republic of); Choi, Jinhee, E-mail: jinhchoi@uos.ac.kr [School of Environmental Engineering and Graduate School of Energy and Environmental System Engineering, University of Seoul, 90 Jeonnong-dong, Dongdaemun-gu, Seoul 130-743 (Korea, Republic of)

    2011-02-15

    In this study, we report the identification and characterization of 13 cytosolic GST genes in Chironomus riparius from Expressed Sequence Tags (ESTs) database generated using pyrosequencing. Comparative and phylogenetic analyses were undertaken with Drosophila melanogaster and Anopheles gambiae GSTs and 3 Delta, 4 Sigma, 1 each in Omega, Epsilon, Theta, Zeta and 2 unclassified classes of GSTs were identified and characterized. The relative mRNA expression levels of all of the C. riparius GSTs (CrGSTs) genes under different developmental stages were varied with low expression in the larval stage. The antioxidant role of CrGSTs was studied by exposing fourth instar larvae to a known oxidative stress inducer Paraquat and the relative mRNA expression to different concentrations of cadmium (Cd) and silver nanoparticles (AgNPs) for various time intervals were also studied. All the CrGSTs showed up- or down regulation to varying levels based upon the concentration, and duration of exposure. The highest mRNA expression was noticed in Delta3, Sigma4 and Epsilon1 GST class in all treatments. These results show the role of CrGST genes in defense against oxidative stress and its potential as a biomarker to Cd and AgNPs exposure.

  20. The role of glutathione transferases in renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Ćorić Vesna

    2016-01-01

    Full Text Available Mounting evidence suggest that members of the subfamily of cytosolic glutathione S-transferases (GSTs possess roles far beyond the classical glutathione-dependent enzymatic conjugation of electrophilic metabolites and xenobiotics. Namely, monomeric forms of certain GSTs are capable of forming protein: protein interactions with protein kinases and regulate cell apoptotic pathways. Due to this dual functionality of cytosolic GSTs, they might be implicated in both the development and the progression of renal cell carcinoma (RCC. Prominent genetic heterogeneity, resulting from the gene deletions, as well as from SNPs in the coding and non-coding regions of GST genes, might affect GST isoenzyme profiles in renal parenchyma and therefore serve as a valuable indicator for predicting the risk of cancer development. Namely, GSTs are involved in the biotransformation of several compounds recognized as risk factors for RCC. The most potent carcinogen of polycyclic aromatic hydrocarbon diol epoxides, present in cigarette smoke, is of benzo(apyrene (BPDE, detoxified by GSTs. So far, the relationship between GST genotype and BPDE-DNA adduct formation, in determining the risk for RCC, has not been evaluated in patients with RCC. Although the association between certain individual and combined GST genotypes and RCC risk has been debated in a the literature, the data on the prognostic value of GST polymorphism in patients with RCC are scarce, probably due to the fact that the molecular mechanism supporting the role of GSTs in RCC progression has not been clarified as yet.

  1. Purification and properties of the glutathione S-transferases from the anoxia-tolerant turtle, Trachemys scripta elegans.

    Science.gov (United States)

    Willmore, William G; Storey, Kenneth B

    2005-07-01

    Glutathione S-transferases (GSTs) play critical roles in detoxification, response to oxidative stress, regeneration of S-thiolated proteins, and catalysis of reactions in nondetoxification metabolic pathways. Liver GSTs were purified from the anoxia-tolerant turtle, Trachemys scripta elegans. Purification separated a homodimeric (subunit relative molecular mass =34 kDa) and a heterodimeric (subunit relative molecular mass = 32.6 and 36.8 kDa) form of GST. The enzymes were purified 23-69-fold and 156-174-fold for homodimeric and heterodimeric GSTs, respectively. Kinetic data gathered using a variety of substrates and inhibitors suggested that both homodimeric and heterodimeric GSTs were of the alpha class although they showed significant differences in substrate affinities and responses to inhibitors. For example, homodimeric GST showed activity with known alpha class substrates, cumene hydroperoxide and p-nitrobenzylchloride, whereas heterodimeric GST showed no activity with cumene hydroperoxide. The specific activity of liver GSTs with chlorodinitrobenzene (CDNB) as the substrate was reduced by 2.6- and 8.7-fold for homodimeric and heterodimeric GSTs isolated from liver of anoxic turtles as compared with aerobic controls, suggesting an anoxia-responsive stable modification of the protein that may alter its function during natural anaerobiosis.

  2. Identification and characterisation of multiple glutathione S-transferase genes from the diamondback moth, Plutella xylostella.

    Science.gov (United States)

    Chen, Xi'en; Zhang, Ya-lin

    2015-04-01

    The diamondback moth (DBM), Plutella xylostella, is one of the most harmful insect pests on crucifer crops worldwide. In this study, 19 cDNAs encoding glutathione S-transferases (GSTs) were identified from the genomic and transcriptomic database for DBM (KONAGAbase) and further characterized. Phylogenetic analysis showed that the 19 GSTs were classified into six different cytosolic classes, including four in delta, six in epsilon, three in omega, two in sigma, one in theta and one in zeta. Two GSTs were unclassified. RT-PCR analysis revealed that most GST genes were expressed in all developmental stages, with higher expression in the larval stages. Six DBM GSTs were expressed at the highest levels in the midgut tissue. Twelve purified recombinant GSTs showed varied enzymatic properties towards 1-chloro-2,4-dinitrobenzene and glutathione, whereas rPxGSTo2, rPxGSTz1 and rPxGSTu2 had no activity. Real-time quantitative PCR revealed that expression levels of the 19 DBM GST genes were varied and changed after exposure to acephate, indoxacarb, beta-cypermethrin and spinosad. PxGSTd3 was significantly overexpressed, while PxGSTe3 and PxGSTs2 were significantly downregulated by all four insecticide exposures. The changes in DBM GST gene expression levels exposed to different insecticides indicate that they may play individual roles in tolerance to insecticides and xenobiotics. © 2014 Society of Chemical Industry.

  3. Versatile Gene-Specific Sequence Tags for Arabidopsis Functional Genomics: Transcript Profiling and Reverse Genetics Applications

    Science.gov (United States)

    Hilson, Pierre; Allemeersch, Joke; Altmann, Thomas; Aubourg, Sébastien; Avon, Alexandra; Beynon, Jim; Bhalerao, Rishikesh P.; Bitton, Frédérique; Caboche, Michel; Cannoot, Bernard; Chardakov, Vasil; Cognet-Holliger, Cécile; Colot, Vincent; Crowe, Mark; Darimont, Caroline; Durinck, Steffen; Eickhoff, Holger; de Longevialle, Andéol Falcon; Farmer, Edward E.; Grant, Murray; Kuiper, Martin T.R.; Lehrach, Hans; Léon, Céline; Leyva, Antonio; Lundeberg, Joakim; Lurin, Claire; Moreau, Yves; Nietfeld, Wilfried; Paz-Ares, Javier; Reymond, Philippe; Rouzé, Pierre; Sandberg, Goran; Segura, Maria Dolores; Serizet, Carine; Tabrett, Alexandra; Taconnat, Ludivine; Thareau, Vincent; Van Hummelen, Paul; Vercruysse, Steven; Vuylsteke, Marnik; Weingartner, Magdalena; Weisbeek, Peter J.; Wirta, Valtteri; Wittink, Floyd R.A.; Zabeau, Marc; Small, Ian

    2004-01-01

    Microarray transcript profiling and RNA interference are two new technologies crucial for large-scale gene function studies in multicellular eukaryotes. Both rely on sequence-specific hybridization between complementary nucleic acid strands, inciting us to create a collection of gene-specific sequence tags (GSTs) representing at least 21,500 Arabidopsis genes and which are compatible with both approaches. The GSTs were carefully selected to ensure that each of them shared no significant similarity with any other region in the Arabidopsis genome. They were synthesized by PCR amplification from genomic DNA. Spotted microarrays fabricated from the GSTs show good dynamic range, specificity, and sensitivity in transcript profiling experiments. The GSTs have also been transferred to bacterial plasmid vectors via recombinational cloning protocols. These cloned GSTs constitute the ideal starting point for a variety of functional approaches, including reverse genetics. We have subcloned GSTs on a large scale into vectors designed for gene silencing in plant cells. We show that in planta expression of GST hairpin RNA results in the expected phenotypes in silenced Arabidopsis lines. These versatile GST resources provide novel and powerful tools for functional genomics. PMID:15489341

  4. Sex differences in apolipoprotein A1 and nevirapine-induced toxicity

    OpenAIRE

    Aline Marinho; Clara Dias; Alexandra Antunes; Umbelina Caixas; Teresa Branco; Matilde Marques; Emília Monteiro; Sofia Pereira

    2014-01-01

    Nevirapine (NVP) is associated with severe liver and skin toxicity through sulfotransferase (SULT) bioactivation of the phase I metabolite 12-hydroxy-NVP [1–3]. The female sex, a well-known risk factor for NVP-induced toxicity, is associated with higher SULT expression [4] and lower plasma levels of 12-hydroxy-NVP [3]. Interestingly, apolipoprotein A1 (ApoA1) increases SULT2B1 activity and ApoA1 synthesis is increased by NVP [5, 6]. Herein, we explore the effect of ApoA1 levels on NVP metabol...

  5. Märt Sultsi kavandatud kasiinosaar vajab 300 miljonit krooni laenu / Kertu Kalmus

    Index Scriptorium Estoniae

    Kalmus, Kertu

    2008-01-01

    Tallinna linnavolikogu liige Märt Sults palub linnavalitsused toetada ja aktsepteerida SA Kasiinosaar laenu taotlemist Saksamaalt 300 mln. krooni ulatuses. Tema ideekavandi järgi kerkiksid Tallinnas Paljassaare lahte tehissaared: lastesaar, kultuurisaar ja kasiinosaar

  6. AJDAS vol 8 No 1.indd

    African Journals Online (AJOL)

    cognitive-behaviour therapy among male patients, self efficacy and religiosity were found to be effective components of cognitive behaviour therapy in substance use disorders as this led to ..... sult of parents and peers drug use, advertising.

  7. Collocations and grammatical patterns in a Multilingual Online Term ...

    African Journals Online (AJOL)

    user

    equivalents for key concepts in the African languages, but also additional con- ... for, inter alia, computational identification and extraction of collocations exist; .... sult' is to be followed by a prepositional phrase in which the preposition is.

  8. Conducting Polymers

    Indian Academy of Sciences (India)

    discovery of dopingl led to a further dramatic increase in ..... sulted in a further drop in forward voltage to about 5 V, and an increase ... microamperometric glucose and galactose blosensors based on a silicon chip employing polypyrrole have.

  9. ORIGINAL ARTICLE

    African Journals Online (AJOL)

    User

    UDS Publishers Limited All Right Reserved 2026-6294. ORIGINAL ... Reproductive development and function in human and other ... sulting solution was filtered and left to stand for three days to ..... male rat brain and pituitary. Brain Res 164,.

  10. Technological and chemical properties of heat-treated Anatolian ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-06-03

    Jun 3, 2009 ... heat treatment temperature and time justifies these re- sults. Cellulose ..... properties of light-irradiated wood with heat treatment: Part 1. Effect ... Norway spruce (Picea abies) and birch (Betula pubescens) subjected to heat ...

  11. Disease: H01321 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available e caused by Streptococcus pneumoniae (pneumococcus). PD is particularly common in younger children and in ol...sult of pneumococcal vaccination in children. However, especially elderly patients with comorbidities remain

  12. The correlation between motor proficiency and physical activity in ...

    African Journals Online (AJOL)

    Lizl-Louise van Niekerk

    eOseretsky Test of Motor Proficiency 2 (BOT-2) for motor proficiency, and the International. Physical Activity ... Pienaar, 2007; Malina, 2012). ..... sults of Hardy, Reinten-Reynolds, Espinel, Zask, and Okely .... Journal of Psychiatric and Mental.

  13. Bioactivation of food genotoxicants 5-hydroxymethylfurfural and furfuryl alcohol by sulfotransferases from human, mouse and rat: a comparative study.

    Science.gov (United States)

    Sachse, Benjamin; Meinl, Walter; Sommer, Yasmin; Glatt, Hansruedi; Seidel, Albrecht; Monien, Bernhard H

    2016-01-01

    5-Hydroxymethylfurfural (HMF) and furfuryl alcohol (FFA) are moderately potent rodent carcinogens that are present in thermally processed foodstuffs. The carcinogenic effects were hypothesized to originate from sulfotransferase (SULT)-mediated bioactivation yielding DNA-reactive and mutagenic sulfate esters, a confirmed metabolic pathway of HMF and FFA in mice. It is known that orthologous SULT forms substantially differ in substrate specificity and tissue distribution. This could influence HMF- and FFA-induced carcinogenic effects. Here, we studied HMF and FFA sulfoconjugation by 30 individual SULT forms of humans, mice and rats. The catalytic efficiencies (k cat/K M) of HMF sulfoconjugation of human SULT1A1 (13.7 s(-1) M(-1)), mouse Sult1a1 (15.8 s(-1) M(-1)) and 1d1 (4.8 s(-1) M(-1)) and rat Sult1a1 (5.3 s(-1) M(-1)) were considerably higher than those of all other SULT forms investigated (≤0.73 s(-1 )M(-1)). FFA sulfoconjugation was monitored using adenosine as a nucleophilic scavenger for the reactive 2-sulfoxymethylfuran (t 1/2 = 20 s at 37 °C). The resulting adduct N (6)-((furan-2-yl)methyl)-adenosine (N (6)-MF-A) was quantified by isotope-dilution UPLC-MS/MS. The rates of N (6)-MF-A formation showed that hSULT1A1 and its orthologues in mice and rats were also the most important contributors to FFA sulfoconjugation in each of the species. Taken together, the catalytic capacity of hSULT1A1 is comparable to that of mSult1a1 in mice, the species in which carcinogenic effects of HMF and FFA were detected. This is of primary concern due to the expression of hSULT1A1 in many different tissues.

  14. Characterization and expression profiling of glutathione S-transferases in the diamondback moth, Plutella xylostella (L.).

    Science.gov (United States)

    You, Yanchun; Xie, Miao; Ren, Nana; Cheng, Xuemin; Li, Jianyu; Ma, Xiaoli; Zou, Minming; Vasseur, Liette; Gurr, Geoff M; You, Minsheng

    2015-03-05

    Glutathione S-transferases (GSTs) are multifunctional detoxification enzymes that play important roles in insects. The completion of several insect genome projects has enabled the identification and characterization of GST genes over recent years. This study presents a genome-wide investigation of the diamondback moth (DBM), Plutella xylostella, a species in which the GSTs are of special importance because this pest is highly resistant to many insecticides. A total of 22 putative cytosolic GSTs were identified from a published P. xylostella genome and grouped into 6 subclasses (with two unclassified). Delta, Epsilon and Omega GSTs were numerically superior with 5 genes for each of the subclasses. The resulting phylogenetic tree showed that the P. xylostella GSTs were all clustered into Lepidoptera-specific branches. Intron sites and phases as well as GSH binding sites were strongly conserved within each of the subclasses in the GSTs of P. xylostella. Transcriptome-, RNA-seq- and qRT-PCR-based analyses showed that the GST genes were developmental stage- and strain-specifically expressed. Most of the highly expressed genes in insecticide resistant strains were also predominantly expressed in the Malpighian tubules, midgut or epidermis. To date, this is the most comprehensive study on genome-wide identification, characterization and expression profiling of the GST family in P. xylostella. The diversified features and expression patterns of the GSTs are inferred to be associated with the capacity of this species to develop resistance to a wide range of pesticides and biological toxins. Our findings provide a base for functional research on specific GST genes, a better understanding of the evolution of insecticide resistance, and strategies for more sustainable management of the pest.

  15. Molecular cloning and expression of five glutathione S-transferase (GST) genes from Banana (Musa acuminata L. AAA group, cv. Cavendish).

    Science.gov (United States)

    Wang, Zhuo; Huang, Suzhen; Jia, Caihong; Liu, Juhua; Zhang, Jianbin; Xu, Biyu; Jin, Zhiqiang

    2013-09-01

    Three tau class MaGSTs responded to abiotic stress, MaGSTF1 and MaGSTL1 responded to signaling molecules, they may play an important role in the growth of banana plantlet. Glutathione S-transferases (GST) are multifunctional detoxification enzymes that participate in a variety of cellular processes, including stress responses. In this study, we report the molecular characteristics of five GST genes (MaGSTU1, MaGSTU2, MaGSTU3, MaGSTF1 and MaGSTL1) cloned from banana (Musa acuminate L. AAA group, cv. Cavendish) using a RACE-PCR-based strategy. The predicted molecular masses of these GSTs range from 23.4 to 27.7 kDa and their pIs are acidic. At the amino acid level, they share high sequence similarity with GSTs in the banana DH-Pahang (AA group) genome. Phylogenetic analysis showed that the deduced amino acid sequences of MaGSTs also have high similarity to GSTs of other plant species. Expression analysis by semi-quantitative RT-PCR revealed that these genes are differentially expressed in various tissues. In addition, their expression is regulated by various stress conditions, including exposure to signaling molecules, cold, salinity, drought and Fusarium oxysporum f specialis(f. Sp) cubense Tropical Race 4 (Foc TR4) infection. The expression of the tau class MaGSTs (MaGSTU1, MaGSTU2 and MaGSTU3) mainly responded to cold, salinity and drought while MaGSTF1 and MaGSTL1 expressions were upregulated by signaling molecules. Our findings suggest that MaGSTs play a key role in both development and abiotic stress responses.

  16. Resistance to the ionizing radiation in cells of human melanoma. Role of the antioxidant enzymes and of the free radicals of the oxygen; Resistencia a la radiacion ionizante en celulas de melanoma humano. Papel de las enzimas antioxidantes y de los radicales libres del oxigeno

    Energy Technology Data Exchange (ETDEWEB)

    Medina, V; Cricco, G; Massari, N; Nunez, M; Martin, G; Mohanad, N; Gutierrez, A; Bergoc, R; Rivera, E [Laboratorio de Radioisotopos, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires, Junin 956, Buenos Aires (Argentina); Crescenti, E; Croci, M [Instituto de Inmunooncologia, Cordoba 3200, Buenos Aires (Argentina)

    2006-07-01

    The malignant melanoma is a highly aggressive and potentially lethal type of skin cancer. Previously we have reported that the cellular human lines of melanoma WM35 and M15 are resistant to the ionizing radiation (IR). The histamine (HA) although it has a regulator effect of the cellular proliferation in these lines, it is not capable of to modify the response to the IR like it makes with other malignant cellular lines. To investigate the bases of the radioresistance of the melanoma lines we have studied in the WM35 the production of free radicals of oxygen (ROS), the activity of the antioxidant enzymes and their modifications by action of the IR and of the HA. In studies in vitro the cells were treated with HA 10 {mu}M from 20 hs before being irradiated with a dose of 2 Gy (source {sup 137}Cs, dose rate 7.7 Gy/min). The ROS levels, superoxide anion (O{sub 2}{sup -}) and hydrogen peroxide (H{sub 2}O{sub 2}) its were measured by flow cytometry using fluorescent coloring and the activity of dismutase superoxide (SOD), Catalase (CAT) and Glutathion Peroxidase (GPx) its were determined by spectrophotometric techniques and the protein levels by Western blot. The results indicate that in the cells WM35 the HA increases the production of H{sub 2}O{sub 2} in 96% and it diminishes lightly (17%) the levels of O{sub 2}{sup -} . On the contrary, the IR diminishes the levels of H{sub 2}O-2 in 47% and it increases in 46% those of O{sub 2}{sup -}. In the irradiated cells the HA power the decrease of H{sub 2}O{sub 2} produced by the IR. The variation of the enzymes activity is coincident with these changes in the levels of ROS: the treatment with HA increases the activity of SOD and it diminishes that of CAT in cells without irradiating; on the other hand, in the irradiated cells the HA it diminishes the SOD significantly. On the base of these results we can conclude that the levels of H{sub 2}O{sub 2} are directly related with the sensitivity of the cells WM35 to the IR. The HA is able to modulate the activity of the antioxidant enzymes and the levels of ROS. The IR activates cellular mechanisms that take to the radioresistance of these cells and that its interfere and/modifying the biological response mediated by the HA. (Author)

  17. Níveis séricos de enzimas de função hepática em frangos de corte de criação industrial clinicamente saudáveis Serum levels of hepatic enzyme function in clinically healthy broiler chickens

    Directory of Open Access Journals (Sweden)

    A. Borsa

    2006-08-01

    Full Text Available The values for the main hepatic enzymes included in the profiles of screen clinical biochemistry, alanine-aminotransferase (ALT, aspartate aminotransferase (AST, alkaline phosphatase (FA, lactate desidrogenase (LDH and gamaglutamiltransferase (GGT, in samples of serum of broiler chickens in industrial system, clinically healthy, starting from the seventh day of life, until the slaughter (42 days in weekly intervals were determined. Significant variations were not observed in the analyses in relation to the age of the birds for none of the appraised enzymes.

  18. Uso de carvão ativado e resina de troca iônica para limpeza e concentração de enzimas em extratos de madeira biodegradada - 10.4025/actascitechnol.v32i4.5671

    Directory of Open Access Journals (Sweden)

    Walter Carvalho

    2010-12-01

    Full Text Available Ceriporiopsis subvermispora foi utilizado para a biodegradação de cavacos de Eucalyptus grandis na presença ou ausência de cossubstratos (glicose e milhocina durante 7, 14 e 28 dias. Os cavacos obtidos em cada um desses períodos foram extraídos com tampão acetato de sódio 50 mM (pH 5,5 adicionado de 0,01% de Tween 60. A atividade de manganês peroxidases (MnPs nos extratos foi marcante ao longo de todo o período de biodegradação, tanto na ausência (430, 765 e 896 UI kg-1, respectivamente quanto na presença de cossubstratos (1.013, 2.066 e 2.323 UI kg-1, respectivamente. Os extratos apresentaram elevadas relações entre absorbância a 280 e a 405 nm, indicando forte abundância de compostos aromáticos derivados da lignina em relação à heme-peroxidases. A adsorção em carvão ativado se mostrou uma estratégia adequada para reduzir a absorbância a 280 nm em todos os extratos. Além disso, permitiu maximizar a capacidade de um leito de resina trocadora de ânions (DEAE Sepharose, utilizado para concentrar as MnPs presentes nos referidos extratos. Concluiu-se que o uso de carvão ativado seguido de adsorção em DEAE Sepharose é uma estratégia que pode ser utilizada para concentrar MnPs em extratos obtidos durante a biodegradação de E. grandis por C. subvermispora.

  19. Asparaginase II-GFP fusion as a tool for studying the secretion of the enzyme under nitrogen starvation Fusão asparaginase II-GFP como ferramenta para estudo da via secretora de enzima sobre depleção por nitrogênio

    Directory of Open Access Journals (Sweden)

    Adriana Sotero-Martins

    2003-12-01

    Full Text Available Production of asparaginase II of Saccharomyces cerevisiae is regulated by nitrogen and can be used as a model system for studying other secreted proteins in yeast. Green fluorescent protein (GFP from Aequorea victoria was fused to the carboxy-terminus of the enzyme by genomic integration to the locus ASP3 of S. cerevisiae. We determined asparaginase II activity, mRNA ASP3, mRNA ASP3-GFP and GFP fluorescence. Nitrogen starvation in cells carrying the chimera ASP3-GFP caused an increase in fluorescence and in the expression of ASP3. We have shown that cells producing the chimera Asp3-GFPp displayed the same response to nitrogen starvation as control cells. We demonstrated that Asp3-GFPp can be used for studying asparaginase II secretion under nitrogen starvation in vivo.A produção de asparaginase II de Saccharomyces cerevisiae é regulada por nitrogênio e pode ser utilizada como um sistema modelo para estudar outras proteínas secretadas, em leveduras. A proteína "green fluorescent protein" (GFP de Aequorea victoria foi fusionada à porção carboxi-terminal de Asp3p por integração genômica da sequência de GFP ao locus ASP3. Determinaram-se os níveis de atividade de asparaginase II, mRNA ASP3, mRNA ASP3-GFP e de fluorescência para GFP. A depleção para nitrogênio, em células portadoras do gene quimérico ASP3-GFP, fez aumentar a fluorescência, assim como a expressão de ASP3. Demonstramos que Asp3-GFPp pode ser utilizada para estudar a secreção de asparaginase II em células submetidas à privação de nitrogênio in vivo.

  20. Effects of albumin administration in serum liver enzymes of rats in the presence of extrahepatic biliary obstruction Efeitos da administração de albumina nos níveis séricos de enzimas hepáticas em ratos com obstrução biliar extra-hepática

    Directory of Open Access Journals (Sweden)

    Jorge Fernando Rebouças Lessa

    2011-01-01

    Full Text Available PURPOSE: To study the influence of albumin on changes of liver function in the extrahepatic biliary obstruction through an experimental model in rats. METHODS: Sixty rats were divided into four groups: Group C (Control: 6 animals. Group M (Fictitious Operation: 18 rats underwent laparotomy and handling of the bile ducts; Groups O (extrahepatic biliary obstruction and A (Treated with 2% albumin: 18 animals in each group underwent ligation of the ductus liver; The animals in groups M, O and A were divided into three subgroups of 6 animals each to be killed in the 7, 14 and 21 days postoperative (POD. Blood was drawn for determination of total bilirubin (TB, indirect bilirubin (IB, direct bilirubin (DB, alkaline phosphatase (ALP, aspartate aminotransferase (AST and alanine aminotransferase (ALT. RESULTS: On POD 7, BI levels were 4.5 mg / dl in group O and 2.1 mg / dl in group A (p = 0.025. On the 14th POD, the levels of PA were 1185.2 U / l in the group and O 458.3 U / l in group A (p = 0.004. ALT levels were 101.7 U / l in the group O and 75.7 U / l in group A (= 0.037. On POD 21, the levels of ALP were 1069.5 U / l in the group O and 468.3 U / l in group A (p = 0, 004. CONCLUSION: The administration of albumin reduced the serum levels of bilirubin in the 7th day of supplementationOBJETIVO: Estudar a influência da albumina em alterações funcionais do fígado na obstrução biliar extra-hepática por meio de um modelo experimental desenvolvido em ratos. MÉTODOS: 60 ratos distribuídos em quatro grupos: Grupo C (Controle: 6 animais. Grupo M (Operação Fictícia: 18 ratos submetidos à laparotomia e manuseio das vias biliares; Grupos O (Obstrução Biliar Extra-hepática e A (Tratados com albumina a 2%: 18 animais, em cada grupo, submetidos à ligadura do ducto hepático; Os animais dos grupos M, O e A foram distribuídos em três subgrupos de 6 animais cada, para serem mortos nos 7°, 14° e 21° dias pós- operatórios (DPO. Foi colhido sangue para dosagem de bilirrubina total (BT, bilirrubina indireta (BI, bilirrubina direta (BD, fosfatase alcalina (FAL, aspartato aminotransferase (AST e alanina aminotransferase (ALT. RESULTADOS: no 7º DPO, os níveis de BI foram 4,5 mg/dl no grupo O e 2,1mg/dl no grupo A (p=0,025. No 14º DPO, os níveis de FAL foram 1185,2 U/l no grupo O e 458,3 U/l no grupo A (p=0,004. Os níveis de ALT foram de 101,7 U/l no grupo O e 75,7 U/l no grupo A (=0,037. No 21º DPO, os níveis de FAL foram de 1069,5 U/l no grupo Oe de 468,3 U/l no grupo A (p =0, 004. CONCLUSÃO: a administração de albumina reduziu os níveis séricos de bilirrubina indireta no 7°dia de suplementação.

  1. Características produtivas e digestibilidade da farinha de folhas de mandioca em dietas de frangos de corte com e sem adição de enzimas Productive traits and digestibility of cassava leaf meal in broiler diets with or without addition of enzymes

    Directory of Open Access Journals (Sweden)

    Hunaldo Oliveira Silva

    2000-06-01

    Full Text Available Experimentos foram realizados a fim de determinar a digestibilidade (Experimento 1 e o efeito da inclusão de farinha de folhas de mandioca (FFM com e sem a adição de complexos multienzimáticos (CME em dietas de frangos de corte machos (Experimento 2, de linhagem Hubbard. Os CME utilizados foram compostos de Energex (beta-glucanase, pectinase, hemicelulase e Bio-Feed Alpha (beta-glucanase, amilase. No Experimento 1, utilizaram-se aves com 21 dias de idade, com o nível de inclusão 0-41,67% de FFM, para medir o coeficiente de digestibilidade da energia bruta e fibra bruta (CDEB/CDFB e determinar os valores de energia metabolizável aparente e corrigida (EMA/EMAn. No Experimento 2, utilizaram-se aves de 1-21 dias de idade, com níveis de inclusão de 0-10,34% de FFM, para avaliar o consumo médio de ração (CMR, o ganho de peso médio (GPM e a conversão alimentar média (CAM. No Experimento 1, houve diferença para os valores do CDEB, CDFB, EMA e EMAn, ocorrendo diminuição na digestibilidade, à medida que se elevaram os níveis de inclusão de FFM na dieta basal. Com a adição dos CME, evidenciou-se melhora nas características analisadas. A determinação dos valores de EMA e EMAn foram de 1697 e 1694 kcal/kg/MS FFM, respectivamente. No Experimento 2, o nível de maior inclusão de FFM foi o que apresentou o pior resultado para as características CMR, GPM e CAM, enquanto o nível 5,17% de FFM não prejudicou o desempenho dos animais. A adição do CME não melhorou o valor nutritivo da FFM.Experiments were carried out to determine the digestibility (Experiment 1 and the effect of the inclusion of cassava leaf meal (CLM with and without the addition of multi-enzyme complexes (MEC in male broiler diets (Experiment 2 of the Hubbard strain. The MECs used were made up of Energex (beta-glucanase, pectinase, hemicellulose and Bio-Feed Alpha (beta-glucanase, amylase. In Experiment 1, birds with 21 days of age were used, with the level of inclusion of 0 - 41.67% of CLM to determine the digestibility coefficient of the gross energy and crude fiber (DCGE/DCCF and to determine the values of apparent and corrected metabolizable energy (AME/nAME. In Experiment 2, birds from 1 to 21 days of age, fed diets with levels of inclusion of 0 - 10.34% of CLM were used to evaluate the average feed intake (DAI, average weight gain (AWG and average feed: gain (AF: G. In Experiment 1, there was difference for the values of DCGE, DCCF, AME and nAME, occurring a decrease on the digestibility as the CLM inclusion levels increased on the basal diet. With the addition of the MECs, an improvement in the analyzed traits was evidenced. The determination of the values of AME and nAME were of 1.697 and 1.694 kcal/Kg/DM CLM, respectively. In Experiment 2, the level of highest inclusion of CLM was the one which presented the poorest result for the traits RAI, AWG and AFC while the level of 5.17% of CLM did not impair the animals performance. The addition of the MEC did not improve the nutritive value of CLM.

  2. Impacto ambiental provocado pelo P em dietas suplementadas com enzima fitase e proteína ideal para suínos em crescimento: estudo do fluxo do P no metabolismo animal Environmental impact provoked by P in diets supplemented with phytase enzyme and ideal protein for growing pigs: study of the P flow in the animal metabolism

    Directory of Open Access Journals (Sweden)

    J.A. Moreira

    2010-10-01

    Full Text Available Avaliou-se a possibilidade de redução da concentração do fósforo inorgânico em dietas formuladas para suínos de acordo com o conceito de proteína ideal, utilizando-se um modelo experimental para o estudo do fluxo do P no metabolismo animal. Utilizaram-se 20 suínos machos castrados em delineamento em blocos ao acaso, com cinco tratamentos e quatro repetições. Os tratamentos corresponderam à adição de 0, 250, 500, 750 e 1000UF/kg de dieta. No primeiro dia da fase experimental, os animais receberam, por via endovenosa, uma solução radioativa com 7,4MBq de 32P. No final do período experimental, os animais foram sacrificados e coletaram-se amostras de tecidos do músculo Longissimus dorsi, coração, fígado, rins e ossos. Pode-se reduzir em 50% a suplementação de P em dietas para suínos em crescimento adicionando-se 750UF/kg de dieta, em rações à base de milho e farelo de soja, balanceadas de acordo com o conceito de proteína ideal, diminuindo-se significativamente a excreção de P nas fezes.The study was developed to evaluate a possible of reduction of the inorganic P concentration in diets formulated for pigs in agreement with the concept of ideal protein, using Lopes et al. model. Twenty male pigs were used in a randomized blocks design, with five treatments and four replicates. The animals were housed in metabolic cages for 17 days, being 10 days for adaptation and seven days for collection of feces and urine. Samples of blood were collected for five days. On the first day of the experimental phase, each animal was intravenously injected with 7.4 MBq 32P. At the end of the experiment, the animals were slaughtered and samples of muscle (loin, heart, liver, kidney, and bones were collected. The supplementation in growing pigs can be reduced in 50% by adding 750UF/kg of diet in rations based in corn and soybean meal, balanced in agreement with concept of ideal protein, decreasing the P fecal excretion.

  3. Análisis de iridoides y expresión de genes que codifican enzimas tempranas en la síntesis de alcaloides indol terpenoicos en Catharanthus roseus Analysis of iridoids content and expression studies of genes encoding early enzymes in the indol terpenoid biosynthesis pathway in Catharanthus roseus

    OpenAIRE

    Palacios-Rojas Natalia; Leech Mark

    2004-01-01

    Los alcaloides indol terpenoicos (TIA) son metabolitos secundarios de importancia medicinal por sus propiedades como agentes anticancerígenos, entre otras. Sin embargo, su explotación en la industria farmacéutica se ha visto limitada, ya que la acumulación de estos compuestos en las plantas que los producen es mínima. Dichos alcaloides son biosintetizados por la vía del shikimato y de los terpenoides, los cuales proveen los precursores: secologanina y triptamina, respectivamente. La secologan...

  4. Analysis of iridoids content and expression studies of genes encoding early enzymes in the indol terpenoid biosynthesis pathway in Catharanthus roseus Análisis de iridoides y expresión de genes que codifican enzimas tempranas en la síntesis de alcaloides indol terpenoicos en Catharanthus roseus

    OpenAIRE

    Leech Mark; Palacios-Rojas Natalia

    2004-01-01

    Terpenoid indole alkaloids (TIA) are of pharmaceutical importance, however the industrial use of these compouds is very limited because its accumulation is very low in plant tissues. TIA are derived f rom the shikimate and terpenoid pathways, which supply secologanin and tryptamine, the indole and iridoid moieties, respectively. Secololganin is a terpenoid which is belived to be synthesised the MEP pathway rather than by the acetate/mevalonic acid pathway. Secologanin is thought to be a limit...

  5. Combinación de un inhibidor de la enzima convertidora de la angiotensina con un antagonista del calcio versus la monoterapia con el IECA: eficacia terapéutica en hipertensión arterial esencial y regresión de la hipertrofia cardíaca

    Directory of Open Access Journals (Sweden)

    Laura M. J. Brandani

    2006-01-01

    Full Text Available Objetivo Evaluar la eficacia y la tolerancia, así como su acción sobre la regresión de la hipertrofia ventricular izquierda, de la combinación de benazepril más amlodipina (B + A versus la monoterapia con benazepril (B. Material y métodos Se incluyeron 33 hipertensos esenciales. Durante 6 meses de tratamiento, 18 de ellos recibieron B + A (9 varones, 55 ± 2 años y los 15 restantes recibieron B (10 varones, 49 ± 2 años. Se realizó una presurometría (MAPA al comienzo y a los 3 y a los 6 meses de tratamiento. En un subgrupo de 23 pacientes se calculó la masa ventricular izquierda (MVI y el índice de MVI (IMVI al inicio y al final del tratamiento. Resultados A los 3 meses de tratamiento, los valores de la presión arterial (PA fueron significativamente menores (p < 0,05 en los pacientes tratados con B + A que con B (24 horas: 123 ± 1,7 / 77 ± 1,8 versus 132 ± 1,5 / 85 ± 1,6 mm Hg; día: 127 ± 1,9 / 81 ± 1,8 versus 137 ± 1,8 / 91 ± 1,9 mm Hg; noche: 115 ± 2,0 / 68 ± 2,1 versus 122 ± 2,0 / 76 ± 1,7 mm Hg. Esto se logró con una dosis menor y hubo mejor tolerancia. En el grupo B + A, la MVI y el IMVI disminuyeron de 225,3 ± 47,4 g y 125,5 ± 19,3 g/m2, a 187,2 ± 45,1 g y 104,7 ± 27,2 g/m2 (p < 0,05, mientras que en el grupo B la disminución no resultó estadísticamente significativa. Al finalizar el tratamiento, sólo en los pacientes tratados con B + A se observó una correlación positiva entre el descenso de la PAS y la MVI (r = 0,56, p < 0,025 y el IMVI (IMVI: r = 0,60; p < 0,01. Conclusión La combinación B + A mostró una reducción de la PA más precoz. Se requirió una dosis menor y se obtuvo mejor tolerancia clínica que con B solo. En relación con la MVI y el IMVI, estos parámetros disminuyeron en forma significativa sólo en B + A.

  6. Frequência de polimorfismos nos genes codificadores das enzimas 17βHSD5 e aromatase em mulheres com diferentes fenótipos da síndrome dos ovários policísticos e resposta ao tratamento com anticoncepcional oral

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    Polyana Sartori Maier

    2012-01-01

    A Síndrome dos Ovários Policísticos (PCOS) é a endocrinopatia mais frequente em mulheres na idade reprodutiva, além de ser a causa mais comum de hiperandrogenismo e anovulação crônica. Diferentes fenótipos da PCOS foram identificados, e um melhor entendimento dessas diferentes apresentações clínicas se faz necessário para o reconhecimento de riscos, medidas preventivas e terapêuticas específicas para cada fenótipo. Associações entre polimorfismos de substituição de um único nucleotídeo (SNPs)...

  7. Influência das proteínas do soro sobre enzimas hepáticas, perfil lipídico e formação óssea de ratos hipercolesterolêmicos Influence of whey protein on liver enzymes, lipid profile and bone formation of hypercholesterolemic rats

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    Fabiano Kenji Haraguchi

    2009-08-01

    Full Text Available OBJETIVO: Avaliar o efeito do consumo das proteínas do soro do leite sobre parâmetros do metabolismo lipídico, hepático e renal, a formação óssea e as defesas antioxidantes de ratos submetidos à dieta hipercolesterolemiante. MÉTODOS: Trinta e dois ratos Fisher adultos foram divididos em 4 grupos, recebendo as seguintes dietas: grupo C, dieta padrão; grupo H, dieta hipercolesterolemiante; grupo PS, dieta padrão e proteínas do soro; grupo PSH dieta hipercolesterolemiante e proteínas do soro. A ingestão alimentar e o ganho de peso foram monitorados semanalmente. Após 8 semanas, o sangue dos animais foi coletado para dosagem bioquímica e os animais foram eutanasiados. Foram utilizados os testes estatísticos, análise de variância e o teste de Tukey. RESULTADOS: As proteínas do soro não reduziram o colesterol plasmático de forma significante, e promoveram um aumento na concentração plasmática de triacilgliceróis nos animais hipercolesterolêmicos. No entanto, reduziram a atividade da aspartato aminotransferase e da fosfatase alcalina, assim como a concentração plasmática de creatinina. Não se observou nenhum efeito sobre as defesas antioxidantes avaliadas. As dietas contendo as proteínas do soro geraram ossos mais pesados, com maior diâmetro e comprimento que as dietas contendo caseína. CONCLUSÃO: As proteínas do soro não apresentaram um efeito hipocolesterolemiante significante em ratos. No entanto, impediram de forma significante a ocorrência de alterações nos parâmetros indicadores das funções hepáticas e renais provocadas pela dieta hipercolesterolemiante. Os dados sugerem também que as proteínas do soro afetam positivamente a formação óssea, quando comparados com as dietas contendo caseína como fonte protéica.OBJECTIVE: The aim of this study was to assess the effect of whey protein consumption on the lipid, hepatic and renal metabolism, bone formation and antioxidant defense system of rats given a hypercholesterolemic diet. METHODS: A total of 32 adult Fisher rats were divided into 4 groups: C group, standard diet; H group, hypercholesterolemic diet; WP group, standard diet with whey protein; WPH group, hypercholesterolemic diet with whey protein. Food ingestion and weight gain were monitored weekly. After 8 weeks, blood was collected for biochemical analysis and the rats were killed. The statistical tests analysis of variance and Tukey's test were performed. RESULTS: Whey protein did not lower serum cholesterol significantly and increased serum triglycerides in hypercholesterolemic rats. However, whey protein decreased the activity of aspartate aminotransferase and alkaline phosphatase, as well as serum creatinine. The assessed antioxidant defenses were not affected. Diets containing whey protein generated heavier, thicker and longer bones than casein diets. CONCLUSION: Whey proteins did not have a significant hypocholesterolemic effect in rats. On the other hand, they significantly prevented changes in liver and kidney functions brought about by hypercholesterolemic diets. Data also suggest that whey proteins benefit bone formation when compared with casein diets.

  8. Involvement of G proteins and cAMP in the production of chitinolytic enzymes by Trichoderma harzianum Envolvimento de proteínas G e cAMP na produção de enzimas quitinolíticas por Trichoderma harzianum

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    Alexandre A.P. Firmino

    2002-06-01

    Full Text Available The effect of G protein modulators and cyclic AMP (cAMP on N-acetylglucosaminidase (NAGase production was investigated during 84 h of growth of a Trichoderma harzianum strain in chitin-containing medium. Caffeine (5 mM, N6--2'-O-dibutyryladenosine 3'5'-cyclic monophosphate sodium salt (dBcAMP (1 mM and 3-isobutyl-1-methylxanthine (IBMX (2 mM decreased extracellular NAGase activity by 80%, 77% and 37%, respectively. AlCl3/KF (100 µM/10 mM and 200 µM/ 20 mM decreased the activity by 85% and 95%, respectively. Cholera (10 µ/mL and pertussis (20 µ/mL toxins also affected NAGase activity, causing a decrease of approximately 75%. Upon all treatments, protein bands of approximately 73 kDa, 68 kDa and 45 kDa had their signals diminished whilst a 50 kDa band was enhanced only by treatment with cholera and pertussis toxins. N-terminal sequencing analysis identified the 73 kDa and 68 kDa proteins as being T. harzianum NAGase in two different truncated forms whereas the 45 kDa band comprised a T. harzianum endochitinase. The 50 kDa protein showed sequence similarity to Coriolus vesicolor cellobiohydrolase. The above results suggest that a signaling pathway comprising G-proteins, adenylate cyclase and cAMP may be involved in the synthesis of T. harzianum chitinases.O efeito de cAMP e de moduladores de proteínas G sobre a produção de N-acetilglicosaminidase (NAGase foi investigado durante o crescimento de Trichoderma harzianum em meio contendo quitina. Cafeína (5 mM, dBcAMP (1mM e IBMX (2 mM provocaram diminuições na atividade extracelular de NAGase em 80%, 77% e 37%, respectivamente. Por outro lado, a presença de AlCl3/KF nas concentrações de 100 µM/10 mM e 200 µM/ 20 mM causou decréscimo na atividade em 85% e 95%, respectivamente. A toxina do cólera (10 µ/mL e a toxina pertussis (20 µ/mL também afetaram a atividade de NAGase, causando um decréscimo de aproximadamente 75%. Análises eletroforéticas mostraram que todos os tratamentos citados causaram diminuição no sinal de bandas correspondendo a polipeptídios de 73 kDa, 68 kDa e 45 kDa, enquanto uma banda de 50 kDa foi intensificada apenas com tratamento com as toxinas do cólera e pertussis. Análises de sequenciamento N-terminal permitiram a identificação das proteínas de 73 kDa e 68 kDa como sendo NAGase de T. harzianum em duas formas diferentemente processadas enquanto a banda de 45 kDa correspondeu a uma endoquitinase de T. harzianum. A proteína de 50 kDa mostrou similaridade de sequência com uma celobiohidrolase de Coriolus vesicolor. Os resultados sugerem que uma via de sinalização composta por proteínas G, adenilato ciclase e cAMP possa estar envolvida na produção de quitinases T. harzianum.

  9. Las poblaciones de Phytophthora infestans presentes en papa en el altiplano Cundiboyacense en 1996 son monomórficas para la enzima glucosa-6-fosfato Isomerasa Populations of Phytophthora infestans present on potato in the Cundinamarca and Boyacá plateau in 1996 are monomorphic for glucose-6-phosphate isomerase

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    Gualtero Cúellar Elsa Janeth

    1998-06-01

    Full Text Available La gota de la papa. causada por Phytophthora infestans. es responsable, en gran medida. de la disminución de la producción de este cultivo en el altiplano Cundiboyacense. Hasta el momento, el control de la gota se ha basado, principalmente, en la aplicación de fungicidas. La observación
    de una mayor variabilidad genética en las poblaciones del patógeno en varios caracteres, incluyendo la sensibilidad a fungicidas. ha mostrado la necesidad de conocer la estructura genética de las poblaciones locales: por esto se realizó una caracterización aloenzimática de las poblaciones de P infestans en Cundinamarca y Boyacá a través de glucosa-6-fosfato isomerasa (GPI lo cual permitió determinar su naturaleza clonal. En efecto todos los aislamientos locales evaluados presentaron genotipo 100/100 para GPI, es decir. fueron homocigotos monomórficos. El aislamiento Ro presentó un genotipo 86/100 que, al ser comparado
    con aislamientos de Estados Unidos, corresponde al linaje US-1. El aislamiento MT2 presentó un genotipo 84/100. Estos aislamientos corresponden a poblaciones heterocigotas que pueden ser el resultado de la reproducción sexual. El aislamiento HIN presentó un genotipo 100/100 coincidiendo con los aislamientos locales: este aislamiento es del tipo de apareamiento A1, y por comparación con aislamientos de Estados Unidos, corresponde al linaje US-6. este linaje representa una de las primeras migraciones de México a Estados Unidos, Europa y luego al resto del mundo anteriores a la migración del tipo A2. Los resultados de los análisis indicaron que las poblaciones locales no presentan diversidad, siendo por tanto de origen clonal; estos resultados están de acuerdo con la evaluación de las mismas poblaciones por  sensibilidad a metalaxil y tipo de apareamiento (González, 1997. Las poblaciones de P infestans de las localidades muestreadas en el altiplano Cundiboyacense son clonales y están constituidas por un sólo genotipo. Esta homogeneidad, en lo que se refiere a GPI en la población, permite concluir que en esta zona predomina la reproducción asexual, a través de la cual la variación genética es mínima o no se presenta. Resultados alternativos como la aparición de genotipos nuevos apoyarían la existencia de migraciones de otras poblaciones o la recombinación sexual explicada por la presencia de los tipos de apareamiento A1 y A2.
    Potato late blight, a disease caused by the Oomycete Phytophthora infestans, is responsible in great proportion for severe decrements in potato production in the Cundinamarca and Boyacá plateaus. Until now, late blight control has been done mainly with fungicides. The widened genetic variability in populations of this organism for a number of traits, including sensitivity to commercially available fungicides, observed in a world-wide perspective, has shown the need to research the genetic structure of local populations. This study was launched to characterize the populations of P. infestans in Cundinamarca and Boyacá through the polymorphism of glucose-6-phosfate isomerase (GPI. The results pointed at a clonal nature of these populations. All the local isolates were homozygous monomorphic for GPI, with genotype 100/100. Isolate Ro showed genotype 86/100 that corresponds to lineage US-1. Isolate MT2 showed genotype 84/100. These iso lates correspond to heterozygous populations that may have resulted from sexual reproduction. Isolate HIN had genotype 100/100, coinciding with local isolates. This isolate belongs to mating type A1 and corresponds to lineage US-6. This lineage represents one of the earliest migrations from Mexico to the United States, Europe and the rest of the world. Prior to the migrations of mating type A2. Results indicate that local populations are not too diverse, and suggest a clonal orrqtn. These results agree with the evaluation of this same population as regards sensitivity to metalaxil and mating type (Gonzalez, 1997. Thus, it appears as if local populations of P. infestans in Cundinamarca and Boyaca on the whole were clonal, and made up of one genotype. From this
    homogeneity in the GPI alleles, one may conclude the prevalence of asexual reproduction, which restricts greatly genetic variation. Different results such as the appearance of novel genotypes would have supported the alternative view of migrations from other populations or sexual recombination involving mating types A1 and A2.

  10. Toxinas killer e produção de enzimas por Candida albicans isoladas da mucosa bucal de pacientes com câncer Killer toxin sensitiviy and production of enzymes by Candida albicans isolated from the oral mucosa of patients with cancer

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    Elida Elias de Oliveira

    1998-12-01

    Full Text Available Infecções oportunistas da cavidade bucal são primariamente causadas por fungos do gênero Candida e freqüentemente ocorrem em pacientes com câncer que estão sobtratamento quimioterápico e antibacteriano. De 44 amostras coletadas da mucosa oral de pacientes com câncer, observou-se o isolamento de 25 leveduras do gênero Candida em cultivo realizado em ágar Sabouraud-dextrose. Foram identificados Candida albicans em 24 (96% isolados e C. krusei em 1 (4%. As características fenotípicas das amostras de Candida albicans mostraram que todos os isolados foram fortemente proteolíticos, capazes de produzir fosfolipases e possuíam os biotipos caracterizados como 811(95,8% e 511 (4,2% em relação a susceptibilidade às toxinas killer.Opportunistic infections of the oral cavity are primarily caused by Candida and frequently occur in patients with cancer who are undergoing chemotherapy and antibiotic treatment. Of the specimens received from the oral mucosa of 44 patients with cancer, 25 (56.8% yielded Candida on culture in Sabouraud agar. Twenty four of these isolates were identified as C. albicans (96% and 1 as C. krusei (4%. The phenotypic characteristics of these isolates showed that all of them were strongly proteolytic, had a high ability to produce phospholipase, and presented the byotypes characterized as 811 (95.8% and 511 (4.2% in terms of susceptibility to killer toxins.

  11. Disponibilidade aparente do fósforo em alimentos vegetais e suplementação da enzima fitase para tilápia-do-nilo Apparent phosphorus availability in vegetable feedstuffs and supplementation of phytase enzyme for Nile tilapia Oreochromis niloticus

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    Giovani Sampaio Gonçalves

    2007-10-01

    Full Text Available Este estudo foi realizado com o objetivo de avaliar o efeito da fitase (0, 1.000 e 2.000 uf/kg na disponibilidade aparente de P de cinco alimentos energéticos (milho, milho extrusado, farelo de trigo, farelo de arroz e sorgo baixo tanino e cinco alimentos protéicos (soja extrusada, farelo de soja, farelo de girassol, farelo de algodão e glúten de milho utilizando-se uma ração purificada como controle. Foram utilizados 100 juvenis (100,00 ± 5,00 g de tilápia-do-nilo (Oreochromis niloticus alojados em dez gaiolas para manejo de alimentação e coleta de fezes. Para cada alimento e cada nível de fitase avaliado, foram coletadas amostras em cinco gaiolas, totalizando cinco repetições por tratamento. Os resultados obtidos indicaram que a suplementação de até 2.000 uf/kg de fitase não aumentou a disponibilidade aparente de P do farelo de trigo e do farelo de algodão. Entretanto, o nível de 1.000 uf/kg aumentou a disponibilidade aparente de P da soja extrusada e do farelo de girassol, enquanto o nível de 2.000 uf/kg proporcionou essa resposta para o farelo de milho, o milho extrusado, o sorgo baixo tanino, o farelo de arroz, o farelo de soja e o glúten de milho.This study was carried out to evaluate effects of phytase (0, 1,000, and 2,000 uf/kg on apparent P availability of five energetic feeds (corn, extruded corn, wheat meal, rice meal and low-tannin sorghum and five protein feeds (extruded soy, soybean meal, sunflower meal, cottonseed meal and corn gluten using a purified diet as control. One hundred (100.00 ± 5.00 g Nile tilapia juveniles (Oreochromis niloticus were allotted to ten cages to allow feeding and fecal collection. For each feed and each phytase level evaluated samples were collected from five cages, in a total of five replications per treatment. The obtained results showed that the phytase supplementation up to 2,000 uf/kg did not increase apparent P availability present in wheat meal or cottonseed meal. However, the level of 1,000 uf/kg increased the apparent P availability present in extruded soy and sunflower meal, while the level of 2,000 uf/kg promoted this response for corn meal, extruded corn, low-tannin sorghum, rice meal, soybean meal and corn gluten.

  12. Perfil fenotípico, diferenciação molecular, produção de enzimas e sensibilidade aos antifúngicos de amostras de leveduras isoladas em três grupos amostrais: mulheres assintomáticas, com candidíase vulvovaginal primária e recorrente.

    OpenAIRE

    Debora Moreira

    2012-01-01

    O presente estudo foi realizado com 258 mulheres, com e sem sintomas de candidíase vulvovaginal, atendidas no Centro de Saúde Geraldo Paula Souza, da Faculdade de Saúde Pública da USP. Leveduras foram isoladas em 162 mulheres, sendo que 34% foram de mulheres assintomáticas, 34% com sintomas de candidíase vulvovaginal primária (CVV) e 32% com candidíase vulvovaginal recorrente (CVVR). As espécies mais isoladas foram C . albicans, C. parapsilosis, C. glabrata e C. tropicalis. Espécies como C. m...

  13. Estrogen sulfotransferases in breast and endometrial cancers.

    Science.gov (United States)

    Pasqualini, Jorge Raul

    2009-02-01

    Estrogen sulfotransferase is significantly more active in the normal breast cell (e.g., Human 7) than in the cancer cell (e.g., MCF-7). The data suggest that in breast cancer sulfoconjugated activity is carried out by another enzyme, the SULT1A, which acts at high concentration of the substrates. In breast cancer cells sulfotransferase (SULT) activity can be stimulated by various progestins: medrogestone, promegestone, and nomegestrol acetate, as well as by tibolone and its metabolites. SULT activities can also be controlled by other substances including phytoestrogens, celecoxib, flavonoids (e.g., quercetin, resveratrol), and isoflavones. SULT expression was localized in breast cancer cells, which can be stimulated by promegestone and correlated with the increase of the enzyme activity. The estrogen sulfotransferase (SULT1E1), which acts at nanomolar concentration of estradiol, can inactivate most of this hormone present in the normal breast; however, in the breast cancer cells, the sulfotransferase denoted as SULT1A1 is mainly present, and this acts at micromolar concentrations of E(2). A correlation was postulated among breast cancer cell proliferation, the effect of various progestins, and sulfotransferase stimulation. In conclusion, it is suggested that factors involved in the stimulation of the estrogen sulfotransferases could provide new possibilities for the treatment of patients with hormone-dependent breast and endometrial cancers.

  14. In silico genome-wide identification and characterization of the glutathione S-transferase gene family in Vigna radiata.

    Science.gov (United States)

    Vaish, Swati; Awasthi, Praveen; Tiwari, Siddharth; Tiwari, Shailesh Kumar; Gupta, Divya; Basantani, Mahesh Kumar

    2018-05-01

    Plant glutathione S-transferases (GSTs) are integral to normal plant metabolism and biotic and abiotic stress tolerance. The GST gene family has been characterized in diverse plant species using molecular biology and bioinformatics approaches. In the current study, in silico analysis identified 44 GSTs in Vigna radiata. Of the total 44 GSTs identified, chromosomal locations of 31 GSTs were confirmed. The pI value of GST proteins ranged from 5.10 to 9.40. The predicted molecular weights ranged from 13.12 to 50 kDa. Subcellular localization analysis revealed that all GSTs were predominantly localized in the cytoplasm. The active site amino acids were confirmed to be serine in tau, phi, theta, zeta, and TCHQD; cysteine in lambda, DHAR, and omega; and tyrosine in EF1G. The gene architecture conformed to the two-exon/one-intron and three-exon/two-intron organization in the case of tau and phi classes, respectively. MEME analysis identified 10 significantly conserved motifs with the width of 8-50 amino acids. The motifs identified were either specific to a specific GST class or were shared by multiple GST classes. The results of the current study will be of potential importance in the characterization of the GST gene family in V. radiata, an economically important leguminous crop.

  15. Glutathione S-Transferases: Role in Combating Abiotic Stresses Including Arsenic Detoxification in Plants

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    Smita Kumar

    2018-06-01

    Full Text Available Arsenic (As, naturally occurring metalloid and a potential hazardous material, is found in low concentrations in the environment and emerges from natural sources and anthropogenic activities. The presence of As in ground water, which is used for irrigation, is a matter of great concern since it affects crop productivity and contaminates food chain. In plants, As alters various metabolic pathways in cells including the interaction of substrates/enzymes with the sulfhydryl groups of proteins and the replacement of phosphate in ATP for energy. In addition, As stimulates the generation of free radicals and reactive oxygen species (ROS, resulting in oxidative stress. Glutathione S-transferases (GSTs quench reactive molecules with the addition of glutathione (GSH and protect the cell from oxidative damage. GSTs are a multigene family of isozymes, known to catalyze the conjugation of GSH to miscellany of electrophilic and hydrophobic substrates. GSTs have been reported to be associated with plant developmental processes and are responsive to multitude of stressors. In past, several studies suggested involvement of plant GST gene family in As response due to the requirement of sulfur and GSH in the detoxification of this toxic metalloid. This review provides updated information about the role of GSTs in abiotic and biotic stresses with an emphasis on As uptake, metabolism, and detoxification in plants. Further, the genetic manipulations that helped in enhancing the understanding of the function of GSTs in abiotic stress response and heavy metal detoxification has been reviewed.

  16. Human cytosolic glutathione-S-transferases: quantitative analysis of expression, comparative analysis of structures and inhibition strategies of isozymes involved in drug resistance.

    Science.gov (United States)

    Mohana, Krishnamoorthy; Achary, Anant

    2017-08-01

    Glutathione-S-transferase (GST) inhibition is a strategy to overcome drug resistance. Several isoforms of human GSTs are present and they are expressed in almost all the organs. Specific expression levels of GSTs in various organs are collected from the human transcriptome data and analysis of the organ-specific expression of GST isoforms is carried out. The variations in the level of expressions of GST isoforms are statistically significant. The GST expression differs in diseased conditions as reported by many investigators and some of the isoforms of GSTs are disease markers or drug targets. Structure analysis of various isoforms is carried out and literature mining has been performed to identify the differences in the active sites of the GSTs. The xenobiotic binding H site is classified into H1, H2, and H3 and the differences in the amino acid composition, the hydrophobicity and other structural features of H site of GSTs are discussed. The existing inhibition strategies are compared. The advent of rational drug design, mechanism-based inhibition strategies, availability of high-throughput screening, target specific, and selective inhibition of GST isoforms involved in drug resistance could be achieved for the reversal of drug resistance and aid in the treatment of diseases.

  17. Molecular characterization of novel sulfotransferases from the tick, Ixodes scapularis

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    King Roberta S

    2011-06-01

    Full Text Available Abstract Background Ixodes scapularis, commonly known as the blacklegged or deer tick, is the main vector of Lyme disease in the United States. Recent progress in transcriptome research has uncovered hundreds of different proteins expressed in the salivary glands of hard ticks, the majority of which have no known function, and include many novel protein families. We recently identified transcripts coding for two putative cytosolic sulfotransferases in these ticks which recognized phenolic monoamines as their substrates. In this current study, we characterize the genetic expression of these two cytosolic sulfotransferases throughout the tick life cycle as well as the enzymatic properties of the corresponding recombinant proteins. Interestingly, the resultant recombinant proteins showed sulfotransferase activity against both neurotransmitters dopamine and octopamine. Results The two sulfotransferase genes were coded as Ixosc SULT 1 & 2 and corresponding proteins were referred as Ixosc Sult 1 and 2. Using gene-specific primers, the sulfotransferase transcripts were detected throughout the blacklegged tick life cycle, including eggs, larvae, nymphs, adult salivary glands and adult midgut. Notably, the mRNA and protein levels were altered upon feeding during both the larval and nymphal life stages. Quantitative PCR results confirm that Ixosc SULT1 was statistically increased upon blood feeding while Ixosc SULT 2 was decreased. This altered expression led us to further characterize the function of these proteins in the Ixodid tick. The sulfotransferase genes were cloned and expressed in a bacterial expression system, and purified recombinant proteins Ixosc Sult 1(R and 2(R showed sulfotransferase activity against neurotransmitters dopamine and octopamine as well as the common sulfotransferase substrate p-nitrophenol. Thus, dopamine- or octopamine-sulfonation may be involved in altering the biological signal for salivary secretion in I. scapularis

  18. In Silico Mechanistic Profiling to Probe Small Molecule Binding to Sulfotransferases

    Science.gov (United States)

    Martiny, Virginie Y.; Carbonell, Pablo; Lagorce, David; Villoutreix, Bruno O.; Moroy, Gautier; Miteva, Maria A.

    2013-01-01

    Drug metabolizing enzymes play a key role in the metabolism, elimination and detoxification of xenobiotics, drugs and endogenous molecules. While their principal role is to detoxify organisms by modifying compounds, such as pollutants or drugs, for a rapid excretion, in some cases they render their substrates more toxic thereby inducing severe side effects and adverse drug reactions, or their inhibition can lead to drug–drug interactions. We focus on sulfotransferases (SULTs), a family of phase II metabolizing enzymes, acting on a large number of drugs and hormones and showing important structural flexibility. Here we report a novel in silico structure-based approach to probe ligand binding to SULTs. We explored the flexibility of SULTs by molecular dynamics (MD) simulations in order to identify the most suitable multiple receptor conformations for ligand binding prediction. Then, we employed structure-based docking-scoring approach to predict ligand binding and finally we combined the predicted interaction energies by using a QSAR methodology. The results showed that our protocol successfully prioritizes potent binders for the studied here SULT1 isoforms, and give new insights on specific molecular mechanisms for diverse ligands’ binding related to their binding sites plasticity. Our best QSAR models, introducing predicted protein-ligand interaction energy by using docking, showed accuracy of 67.28%, 78.00% and 75.46%, for the isoforms SULT1A1, SULT1A3 and SULT1E1, respectively. To the best of our knowledge our protocol is the first in silico structure-based approach consisting of a protein-ligand interaction analysis at atomic level that considers both ligand and enzyme flexibility, along with a QSAR approach, to identify small molecules that can interact with II phase dug metabolizing enzymes. PMID:24039991

  19. In silico mechanistic profiling to probe small molecule binding to sulfotransferases.

    Directory of Open Access Journals (Sweden)

    Virginie Y Martiny

    Full Text Available Drug metabolizing enzymes play a key role in the metabolism, elimination and detoxification of xenobiotics, drugs and endogenous molecules. While their principal role is to detoxify organisms by modifying compounds, such as pollutants or drugs, for a rapid excretion, in some cases they render their substrates more toxic thereby inducing severe side effects and adverse drug reactions, or their inhibition can lead to drug-drug interactions. We focus on sulfotransferases (SULTs, a family of phase II metabolizing enzymes, acting on a large number of drugs and hormones and showing important structural flexibility. Here we report a novel in silico structure-based approach to probe ligand binding to SULTs. We explored the flexibility of SULTs by molecular dynamics (MD simulations in order to identify the most suitable multiple receptor conformations for ligand binding prediction. Then, we employed structure-based docking-scoring approach to predict ligand binding and finally we combined the predicted interaction energies by using a QSAR methodology. The results showed that our protocol successfully prioritizes potent binders for the studied here SULT1 isoforms, and give new insights on specific molecular mechanisms for diverse ligands' binding related to their binding sites plasticity. Our best QSAR models, introducing predicted protein-ligand interaction energy by using docking, showed accuracy of 67.28%, 78.00% and 75.46%, for the isoforms SULT1A1, SULT1A3 and SULT1E1, respectively. To the best of our knowledge our protocol is the first in silico structure-based approach consisting of a protein-ligand interaction analysis at atomic level that considers both ligand and enzyme flexibility, along with a QSAR approach, to identify small molecules that can interact with II phase dug metabolizing enzymes.

  20. THE ROLES OF DETOXIFYING ENZYMES AND AChE INSENSITIVITY IN METHAMIDOPHOS RESISTANCE DEVELOPMENT AND DECLINE IN NILAPARVATA LUGENS

    Institute of Scientific and Technical Information of China (English)

    Ze-wenLiu; Zhao-junHan; Ling-chunZhang

    2003-01-01

    Methamidophos resistance of brown planthopper (Nilaparvata lugens Stal, BPH) was selected in laboratory. After successive selection for 9 generations, the selection was ceased by rearing BPH without contact with any insecticide for 9 generations. In the full course, the successive changes of esterase activity, MFO activity, GSTs activity and AChE insensitivity were analyzed. The results showed that the change of esterase activity was high correlated with that of methamidophos in the full course, which indicated that esterase played very important role both in the resistance development and in the resistance decline. However, the change of AChE insensitivity only significantly correlated with that of resistance in the development stage, and the change of MFO activity or GSTs activity only significantly correlated with that of the resistance in the decline stage, which indicated the changes of AChE insensitivity, MFO activity or GSTs activity only played some roles in different stages of the resistance change.

  1. Comparative structural analysis of a novel glutathioneS-transferase (ATU5508) from Agrobacterium tumefaciens at 2.0 A resolution.

    Science.gov (United States)

    Kosloff, Mickey; Han, Gye Won; Krishna, S Sri; Schwarzenbacher, Robert; Fasnacht, Marc; Elsliger, Marc-André; Abdubek, Polat; Agarwalla, Sanjay; Ambing, Eileen; Astakhova, Tamara; Axelrod, Herbert L; Canaves, Jaume M; Carlton, Dennis; Chiu, Hsiu-Ju; Clayton, Thomas; DiDonato, Michael; Duan, Lian; Feuerhelm, Julie; Grittini, Carina; Grzechnik, Slawomir K; Hale, Joanna; Hampton, Eric; Haugen, Justin; Jaroszewski, Lukasz; Jin, Kevin K; Johnson, Hope; Klock, Heath E; Knuth, Mark W; Koesema, Eric; Kreusch, Andreas; Kuhn, Peter; Levin, Inna; McMullan, Daniel; Miller, Mitchell D; Morse, Andrew T; Moy, Kin; Nigoghossian, Edward; Okach, Linda; Oommachen, Silvya; Page, Rebecca; Paulsen, Jessica; Quijano, Kevin; Reyes, Ron; Rife, Christopher L; Sims, Eric; Spraggon, Glen; Sridhar, Vandana; Stevens, Raymond C; van den Bedem, Henry; Velasquez, Jeff; White, Aprilfawn; Wolf, Guenter; Xu, Qingping; Hodgson, Keith O; Wooley, John; Deacon, Ashley M; Godzik, Adam; Lesley, Scott A; Wilson, Ian A

    2006-11-15

    Glutathione S-transferases (GSTs) comprise a diverse superfamily of enzymes found in organisms from all kingdoms of life. GSTs are involved in diverse processes, notably small-molecule biosynthesis or detoxification, and are frequently also used in protein engineering studies or as biotechnology tools. Here, we report the high-resolution X-ray structure of Atu5508 from the pathogenic soil bacterium Agrobacterium tumefaciens (atGST1). Through use of comparative sequence and structural analysis of the GST superfamily, we identified local sequence and structural signatures, which allowed us to distinguish between different GST classes. This approach enables GST classification based on structure, without requiring additional biochemical or immunological data. Consequently, analysis of the atGST1 crystal structure suggests a new GST class, distinct from previously characterized GSTs, which would make it an attractive target for further biochemical studies. (c) 2006 Wiley-Liss, Inc.

  2. Modulation of xenobiotic metabolising enzymes by anticarcinogens-focus on glutathione S-transferases and their role as targets of dietary chemoprevention in colorectal carcinogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Pool-Zobel, Beatrice [Department of Nutritional Toxicology, Institute for Nutrition, Friedrich Schiller University Jena, 07743 Jena (Germany)]. E-mail: b8pobe@uni-jena.de; Veeriah, Selvaraju [Department of Nutritional Toxicology, Institute for Nutrition, Friedrich Schiller University Jena, 07743 Jena (Germany); Boehmer, Frank-D. [Institute of Molecular Cell Biology, University Hospital, Friedrich Schiller University Jena, 07743 Jena (Germany)

    2005-12-11

    There is evidence that consumption of certain dietary ingredients may favourably modulate biotransformation of carcinogens. Associated with this is the hypothesis that the risk for developing colorectal cancer could be reduced, since its incidence is related to diet. Two main groups of biotransformation enzymes metabolize carcinogens, namely Phase I enzymes, which convert hydrophobic compounds to more water-soluble moieties, and Phase II enzymes (e.g. glutathione S-transferases [GST]), which primarily catalyze conjugation reactions. The conjugation of electrophilic Phase I intermediates with glutathione, for instance, frequently results in detoxification. Several possible colon carcinogens may serve as substrates for GST isoenzymes that can have marked substrate specificity. The conjugated products could be less toxic/genotoxic if GSTs are induced, thereby reducing exposure. Thus, numerous studies have shown that the induction of GSTs by antioxidants enables experimental animals to tolerate exposure to carcinogens. One important mechanism of GST induction involves an antioxidant-responsive response element (ARE) and the transcription factor nuclear factor E2-related factor 2 (Nrf2), which is bound to the Kelch-like ECH associated protein 1 (Keap1) in the cytoplasm. Antioxidants may disrupt the Keap-Nrf2 complex, allowing Nrf2 to translocate to the nucleus and mediate expression of Phase II genes via interaction with the ARE. GSTs are also induced by butyrate, a product of gut flora-derived fermentation of plant foods, which may act via different mechanisms, e.g. by increasing histone acetylation. GSTs are expressed with high inter-individual variability in human colonocytes, which points to large differences in cellular susceptibility to xenobiotics. Enhancing expression of GSTs in human colon tissue could therefore contribute to reducing cancer risks. However, it has not been demonstrated in humans that this mechanism is associated with cancer prevention. In the

  3. Modulation of xenobiotic metabolising enzymes by anticarcinogens-focus on glutathione S-transferases and their role as targets of dietary chemoprevention in colorectal carcinogenesis

    International Nuclear Information System (INIS)

    Pool-Zobel, Beatrice; Veeriah, Selvaraju; Boehmer, Frank-D.

    2005-01-01

    There is evidence that consumption of certain dietary ingredients may favourably modulate biotransformation of carcinogens. Associated with this is the hypothesis that the risk for developing colorectal cancer could be reduced, since its incidence is related to diet. Two main groups of biotransformation enzymes metabolize carcinogens, namely Phase I enzymes, which convert hydrophobic compounds to more water-soluble moieties, and Phase II enzymes (e.g. glutathione S-transferases [GST]), which primarily catalyze conjugation reactions. The conjugation of electrophilic Phase I intermediates with glutathione, for instance, frequently results in detoxification. Several possible colon carcinogens may serve as substrates for GST isoenzymes that can have marked substrate specificity. The conjugated products could be less toxic/genotoxic if GSTs are induced, thereby reducing exposure. Thus, numerous studies have shown that the induction of GSTs by antioxidants enables experimental animals to tolerate exposure to carcinogens. One important mechanism of GST induction involves an antioxidant-responsive response element (ARE) and the transcription factor nuclear factor E2-related factor 2 (Nrf2), which is bound to the Kelch-like ECH associated protein 1 (Keap1) in the cytoplasm. Antioxidants may disrupt the Keap-Nrf2 complex, allowing Nrf2 to translocate to the nucleus and mediate expression of Phase II genes via interaction with the ARE. GSTs are also induced by butyrate, a product of gut flora-derived fermentation of plant foods, which may act via different mechanisms, e.g. by increasing histone acetylation. GSTs are expressed with high inter-individual variability in human colonocytes, which points to large differences in cellular susceptibility to xenobiotics. Enhancing expression of GSTs in human colon tissue could therefore contribute to reducing cancer risks. However, it has not been demonstrated in humans that this mechanism is associated with cancer prevention. In the

  4. Overlapping protective roles for glutathione transferase gene family members in chemical and oxidative stress response in Agrobacterium tumefaciens.

    Science.gov (United States)

    Skopelitou, Katholiki; Muleta, Abdi W; Pavli, Ourania; Skaracis, Georgios N; Flemetakis, Emmanouil; Papageorgiou, Anastassios C; Labrou, Nikolaos E

    2012-03-01

    In the present work, we describe the characterisation of the glutathione transferase (GST) gene family from Agrobacterium tumefaciens C58. A genome survey revealed the presence of eight GST-like proteins in A. tumefaciens (AtuGSTs). Comparison by multiple sequence alignment generated a dendrogram revealing the phylogenetic relationships of AtuGSTs-like proteins. The beta and theta classes identified in other bacterial species are represented by five members in A. tumefaciens C58. In addition, there are three "orphan" sequences that do not fit into any previously recognised GST classes. The eight GST-like genes were cloned, expressed in Escherichia coli and their substrate specificity was determined towards 17 different substrates. The results showed that AtuGSTs catalyse a broad range of reactions, with different members of the family exhibiting quite varied substrate specificity. The 3D structures of AtuGSTs were predicted using molecular modelling. The use of comparative sequence and structural analysis of the AtuGST isoenzymes allowed us to identify local sequence and structural characteristics between different GST isoenzymes and classes. Gene expression profiling was conducted under normal culture conditions as well as under abiotic stress conditions (addition of xenobiotics, osmotic stress and cold and heat shock) to induce and monitor early stress-response mechanisms. The results reveal the constitutive expression of GSTs in A. tumefaciens and a modulation of GST activity after treatments, indicating that AtuGSTs presumably participate in a wide range of functions, many of which are important in counteracting stress conditions. These functions may be relevant to maintaining cellular homeostasis as well as in the direct detoxification of toxic compounds.

  5. Molecular evolution and the role of oxidative stress in the expansion and functional diversification of cytosolic glutathione transferases

    Directory of Open Access Journals (Sweden)

    Vasconcelos Vítor

    2010-09-01

    Full Text Available Abstract Background Cytosolic glutathione transferases (cGST are a large group of ubiquitous enzymes involved in detoxification and are well known for their undesired side effects during chemotherapy. In this work we have performed thorough phylogenetic analyses to understand the various aspects of the evolution and functional diversification of cGSTs. Furthermore, we assessed plausible correlations between gene duplication and substrate specificity of gene paralogs in humans and selected species, notably in mammalian enzymes and their natural substrates. Results We present a molecular phylogeny of cytosolic GSTs that shows that several classes of cGSTs are more ubiquitous and thus have an older ancestry than previously thought. Furthermore, we found that positive selection is implicated in the diversification of cGSTs. The number of duplicate genes per class is generally higher for groups of enzymes that metabolize products of oxidative damage. Conclusions 1 Protection against oxidative stress seems to be the major driver of positive selection in mammalian cGSTs, explaining the overall expansion pattern of this subfamily; 2 Given the functional redundancy of GSTs that metabolize xenobiotic chemicals, we would expect the loss of gene duplicates, but by contrast we observed a gene expansion of this family, which likely has been favored by: i the diversification of endogenous substrates; ii differential tissue expression; and iii increased specificity for a particular molecule; 3 The increased availability of sequence data from diversified taxa is likely to continue to improve our understanding of the early origin of the different cGST classes.

  6. Association of GSTO1 and GSTO2 Polymorphism with Risk of End-Stage Renal Disease Development and Patient Survival

    Directory of Open Access Journals (Sweden)

    Cimbaljevic Slavica

    2016-09-01

    Full Text Available Background: Oxidative stress in patients with end-stage renal disease (ESRD is associated with long-term cardiovascular complications. The cytosolic family of glutathione S-transferases (GSTs is involved in the detoxication of various toxic compounds and antioxidant protection. GST omega class members, GSTO1 and GSTO2 possess, unlike other GSTs, dehydroascorbate reductase and deglutathionylation activities. The aim of this study was to clarify the role of genetic polymorphisms of GSTO1 (rs4925 and GSTO2 (rs156697 as risk determinants for ESRD development, as well as in the survival of these patients.

  7. Phylogenomic approaches to common problems encountered in the analysis of low copy repeats: The sulfotransferase 1A gene family example

    Directory of Open Access Journals (Sweden)

    Benner Steven A

    2005-03-01

    Full Text Available Abstract Background Blocks of duplicated genomic DNA sequence longer than 1000 base pairs are known as low copy repeats (LCRs. Identified by their sequence similarity, LCRs are abundant in the human genome, and are interesting because they may represent recent adaptive events, or potential future adaptive opportunities within the human lineage. Sequence analysis tools are needed, however, to decide whether these interpretations are likely, whether a particular set of LCRs represents nearly neutral drift creating junk DNA, or whether the appearance of LCRs reflects assembly error. Here we investigate an LCR family containing the sulfotransferase (SULT 1A genes involved in drug metabolism, cancer, hormone regulation, and neurotransmitter biology as a first step for defining the problems that those tools must manage. Results Sequence analysis here identified a fourth sulfotransferase gene, which may be transcriptionally active, located on human chromosome 16. Four regions of genomic sequence containing the four human SULT1A paralogs defined a new LCR family. The stem hominoid SULT1A progenitor locus was identified by comparative genomics involving complete human and rodent genomes, and a draft chimpanzee genome. SULT1A expansion in hominoid genomes was followed by positive selection acting on specific protein sites. This episode of adaptive evolution appears to be responsible for the dopamine sulfonation function of some SULT enzymes. Each of the conclusions that this bioinformatic analysis generated using data that has uncertain reliability (such as that from the chimpanzee genome sequencing project has been confirmed experimentally or by a "finished" chromosome 16 assembly, both of which were published after the submission of this manuscript. Conclusion SULT1A genes expanded from one to four copies in hominoids during intra-chromosomal LCR duplications, including (apparently one after the divergence of chimpanzees and humans. Thus, LCRs may

  8. Producción de endoproteasa ácida extracelular (mrAE) por el hongo fitopatógeno Moniliophthora roreri cultivado en el sistema de fermentación en el estado sólido con bagazo de caña de azúcar como sustrato.

    OpenAIRE

    Soberano Mayo, María Isabel

    2012-01-01

    Las proteasas son enzimas industriales muy importantes y comprenden alrededor del 60% de las enzimas comerciales en el mundo. Dos terceras partes de estas proteasas son de fuentes microbianas, principalmente de origen fúngico. El presente trabajo tuvo como objetivos estudiar la cinética de producción de enzima endoproteasa ácida extracelular (mrAe) del hongo fitopatógeno Moniliophthora roreri MRO1, cultivado en sistema de fermentación en estado sólido (FES), utilizando como sustrato inductor ...

  9. Desenvolvimento de novas tecnologias para produção de xarope de glicose a partir do amido

    OpenAIRE

    Freitas, Aline Costa de [UNESP

    2012-01-01

    As amilases são enzimas que catalisam a hidrólise do amido, dentre as quais se destaca a α-amilase, a β-amilase e a glicoamilase. Apresentam grande importância biotecnológica devido sua aplicação em vários processos industriais, principalmente alimentício. Podem ser obtidas de plantas, animais e microorganismos, no entanto, enzimas microbianas encontram maior demanda industrial. Além da importância econômica destas enzimas, novas metodologias têm sido desenvolvidas com resíduos como substrato...

  10. Avaliação da produção de lipases por diferentes cepas de microrganismos isolados em efluentes de laticínios por fermentação submersa Evaluation of lipase production using different strains of microorganisms isolated from dairy effluent through submerged fermentation

    OpenAIRE

    Mirela Roveda; Marcelo Hemkemeier; Luciane Maria Colla

    2010-01-01

    A produção enzimática é um dos campos mais promissores dentro das tecnologias para a síntese de compostos de alto valor agregado, estando em constante crescimento pela grande capacidade dos microrganismos de realizarem transformações químicas. As enzimas produzidas por processos fermentativos têm sido utilizadas para o controle ambiental. Muitas destas enzimas podem ser produzidas a partir de resíduos industriais, diminuindo os custos de produção. As lipases são enzimas que catalisam a hidról...

  11. Avaliação da produção de lipases por diferentes cepas de microrganismos isolados em efluentes de laticínios por fermentação submersa

    OpenAIRE

    Roveda,Mirela; Hemkemeier,Marcelo; Colla,Luciane Maria

    2010-01-01

    A produção enzimática é um dos campos mais promissores dentro das tecnologias para a síntese de compostos de alto valor agregado, estando em constante crescimento pela grande capacidade dos microrganismos de realizarem transformações químicas. As enzimas produzidas por processos fermentativos têm sido utilizadas para o controle ambiental. Muitas destas enzimas podem ser produzidas a partir de resíduos industriais, diminuindo os custos de produção. As lipases são enzimas que catalisam a hidról...

  12. Inmovilización de lacasa : métodos y potenciales aplicaciones industriales

    OpenAIRE

    Fernández Fernández, María

    2013-01-01

    La utilización de enzimas en el sector industrial supone un gran avance para muchos procesos antes realizados mediante reacciones químicas. Desde el punto de vista ambiental la utilización de enzimas en lugar de otro tipo de catalizadores para reacciones de tipo industrial mejora notablemente el impacto ambiental que generan este tipo de procesos. El empleo de estos biocatalizadores está limitado por su escasa estabilidad y alto coste, por lo que la inmovilización de enzimas podría superar es...

  13. INVESTIGACION, DESARROLLO Y PRODUCCION DE PROTEASAS Y LIPASAS CREIOFILICAS COMERCIALES DE KRILL Y BACTERIAS ANTARTICAS

    OpenAIRE

    ASENJO DE LEUZE, JUAN ALFONSO

    2005-01-01

    El uso de enzimas a bajas temperaturas posee un gran potencial, fundamentalmente por los menores costos en el uso de energía. Los organismos antárticos son muy interesantes como fuente de enzimas de propiedades únicas, específicamente de proteasas y lipasas que poseen altas actividades a bajas temperaturas (criofílicas), ideales para ser utilizadas como enzimas de detergentes. Esto ha sido demostrado claramente en dos proyectos Fondef anteriores que fueron exitosos. Además no existen hoy en d...

  14. Produção e caracterização de aromas de frutas por microrganismos pectinoliticos utilizando-se residuos agroindustriais.

    OpenAIRE

    Mariana Uenojo

    2003-01-01

    Resumo: As pectinases foram algumas das primeiras enzimas a serem utilizadas comercialmente nas preparações de vinhos e sucos de frutas na década de 1930 e seu uso tem aumentado consideravelmente, especialmente nas indústrias de alimentos, bebidas e vinhos, têxtil e de papel e celulose. Atualmente essas enzimas correspondem à cerca de 20% do mercado mundial de enzimas e são produzidas naturalmente por plantas, fungos, leveduras e bactérias. Estes microrganismos podem ser inoculados em meios c...

  15. El aumento de la expresión del ARNm de la enzima convertidora de angiotensina I homóloga (ECA-2 inducido por atorvastatina se asocia a menor fibrosis e hipertrofia ventricular izquierda en un modelo de cardiomiopatía diabética Atorvastatin induced increase in homologous angiotensin i converting enzyme (ACE2 mRNA is associated to decreased fibrosis and decreased left ventricular hypertrophy in a rat model of diabetic cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Cristian Aguilar

    2011-06-01

    Full Text Available Objetivos. Evaluar el efecto de atorvastatina sobre la progresión del remodelado cardiaco y la expresión de ECA-2 en el miocardio de ratas diabéticas. Materiales y métodos. La diabetes fue inducida en ratas Holtzman con una inyección intraperitoneal de estreptozotocina. Los animales fueron divididos en tres grupos: (1 ratas control, (2 ratas diabéticas y (3 ratas diabéticas tratadas con atorvastatina (50 mg/kg/día. Después de ocho semanas de tratamiento, los corazones fueron extraídos para el análisis morfométrico, la cuantificación de colágeno y la determinación de los niveles de ARNm de ECA y ECA-2. Resultados. El índice de hipertrofia ventricular y el depósito de colágeno se incrementaron significativamente en las ratas diabéticas. La administración de atorvastatina previno estos cambios sin modificar los niveles de colesterol. La hiperglicemia produjo un incremento significativo en los niveles del ARNm de ECA y una marcada disminución en la expresión de ECA-2 en el miocardio de ratas diabéticas. La administración de atorvastatina indujo la expresión del ARNm de ECA-2 e inhibió la sobreexpresión del ARNm de ECA en el miocardio de las ratas diabéticas. Conclusiones. Nuestros resultados indican que la atorvastatina, independientemente de su capacidad para disminuir el colesterol, normaliza la relación de la expresión de ECA/ECA-2 y atenúa el desarrollo del remodelado adverso en el corazón diabético.Objectives. This study has investigated the effect of atorvastatin on the progression of cardiac remodelling and ACE- 2 expression in diabetic myocardium in rats. Materials and Methods. Diabetes was induced in Holtzman rats with an intraperitoneal injection of streptozotocin. The animals were divided into 3 groups: (1 normal control rats, (2 diabetic rats and (3 diabetic rats treated orally with atorvastatin (50 mg/kg/day. After eight weeks of treatment, the hearts were removed for morphometric studies, collagen content assay and genetic expressions of ACE and ACE2 mRNA. Results. Myocardial hypertrophy index and collagen deposition were increased in diabetic rats, but not in the treated-diabetic rats, without producing changes in cholesterol levels. Myocardial ACE mRNA levels were increased while ACE2 mRNA levels were decreased in diabetic rats. Atorvastatin administration attenuated overexpression of ACE mRNA and overexpression of ACE-2 mRNA in diabetic rats. Conclusions. Our results indicate that atorvastatin, independently of its cholesterol-lowering capacity, lowers the ACE/ACE2 ratio to normal values and attenuates the development of adverse remodeling in the diabetic heart.

  16. Evaluation of the effects of S-methylisothiourea hemisulfate, an inducible nitric oxide synthase inhibitor, on the healing of colonic anastomosis in rats Avaliação dos efeitos da S-metilisotiouréia, um inibidor da enzima óxido nítrico sintase induzível, na cicatrização de anastomoses colônicas em ratos

    Directory of Open Access Journals (Sweden)

    Romulo Medeiros de Almeida

    2012-12-01

    Full Text Available PURPOSE: To evaluate the effects of S-methylisothiourea hemisulfate (SMT on the healing of colonic anastomosis in rats. METHODS: Sixty rats Wistar were distributed into two groups of 30 animals: experimental (E and control C. The animals of experimental group received intraperitoneal SMT at 50mg/kg/dose every 12 hours for 72 hours. The control group received intraperitoneal saline at the same volume of SMT. The rats were subdivided into subgroups groups of 10 for euthanasia on the third, seventh, and 14th postoperative days (POD. We evaluated clinical and weight evolution, breaking strength and histopathology; also, a blood sample was collected for serum dosage of nitrite/nitrate. RESULTS: There was more vascular neoformation (p=0.006 and granulation (p=0.002 in the E3 group, and more mononuclear infiltrates in the C3 group (p=0.041. There was also more edema in the C14 group (p=0.008. There was no statistically significant difference in breaking strength, nitrite/nitrate dosage, and the remaining histopathological parameters. CONCLUSION: The use of S-methylisothiourea hemisulfate improved the healing of colonic anastomosis in rats on the third postoperative day by accelerating the proliferative stage of healing, but without interfering with the breaking strength of the anastomosis.OBJETIVO: Avaliar os efeitos do hemissulfato de S-metilisotiouréia (SMT na cicatrização de anastomoses colônicas em ratos no terceiro, sétimo e 14° dia de pós-operatório (DPO. MÉTODOS: Sessenta ratos Wistar foram distribuídos em dois grupos: experimental (E e controle (C, com 30 animais cada. No grupo experimental foi administrado SMT 50mg/kg/dose, intraperitoneal a cada 12 horas por 72 horas. O grupo controle recebeu NaCl a 0,9%. Os ratos foram subdivididos em grupos de 10 para eutanásia no terceiro, sétimo e 14° DPO. Avaliou-se a evolução clínica e o peso dos animais, a resistência tênsil e histopatologia da anastomose, e a dosagem de nitrito/nitrato no soro. RESULTADOS: Houve mais neoformação vascular (p=0,006 e de granulação (p=0,002 no grupo E3, e maior infiltração de mononucleares no grupo C3 (p=0,041. Houve também mais edema no grupo C14 (p=0,008. Não houve diferença estatisticamente significativa na resistência tênsil, a dosagem de nitrito / nitrato, e os restantes parâmetros histopatológicos. CONCLUSÃO: A utilização do hemissulfato de S-metilisotiouréia acelerou a cicatrização das anastomoses colônicas, a melhoria ocorreu no terceiro DPO: verificou-se que a fase proliferativa da cicatrização foi acelerada. Não houve interferência na resistência tênsil das anastomoses.

  17. High accuracy in silico sulfotransferase models.

    Science.gov (United States)

    Cook, Ian; Wang, Ting; Falany, Charles N; Leyh, Thomas S

    2013-11-29

    Predicting enzymatic behavior in silico is an integral part of our efforts to understand biology. Hundreds of millions of compounds lie in targeted in silico libraries waiting for their metabolic potential to be discovered. In silico "enzymes" capable of accurately determining whether compounds can inhibit or react is often the missing piece in this endeavor. This problem has now been solved for the cytosolic sulfotransferases (SULTs). SULTs regulate the bioactivities of thousands of compounds--endogenous metabolites, drugs and other xenobiotics--by transferring the sulfuryl moiety (SO3) from 3'-phosphoadenosine 5'-phosphosulfate to the hydroxyls and primary amines of these acceptors. SULT1A1 and 2A1 catalyze the majority of sulfation that occurs during human Phase II metabolism. Here, recent insights into the structure and dynamics of SULT binding and reactivity are incorporated into in silico models of 1A1 and 2A1 that are used to identify substrates and inhibitors in a structurally diverse set of 1,455 high value compounds: the FDA-approved small molecule drugs. The SULT1A1 models predict 76 substrates. Of these, 53 were known substrates. Of the remaining 23, 21 were tested, and all were sulfated. The SULT2A1 models predict 22 substrates, 14 of which are known substrates. Of the remaining 8, 4 were tested, and all are substrates. The models proved to be 100% accurate in identifying substrates and made no false predictions at Kd thresholds of 100 μM. In total, 23 "new" drug substrates were identified, and new linkages to drug inhibitors are predicted. It now appears to be possible to accurately predict Phase II sulfonation in silico.

  18. Polymorphisms in the GST (M1 andT1) gene and their possible ...

    African Journals Online (AJOL)

    Glutathione S-transferases (GSTs) are enzymes involved in the detoxification of several environmental mutagens, carcinogens and anticancer drugs. GST polymorphisms resulting in decreased enzymatic activity have been associated with several types of solid tumors. We determined the frequencies of the deletion of two ...

  19. Proteomic Profiling of Cytosolic Glutathione Transferases from Three Bivalve Species: Corbicula fluminea, Mytilus galloprovincialis and Anodonta cygnea

    Directory of Open Access Journals (Sweden)

    José Carlos Martins

    2014-01-01

    Full Text Available Suspension-feeding bivalves are considered efficient toxin vectors with a relative insensitivity to toxicants compared to other aquatic organisms. This fact highlights the potential role of detoxification enzymes, such as glutathione transferases (GSTs, in this bivalve resistance. Nevertheless, the GST system has not been extensively described in these organisms. In the present study, cytosolic GSTs isoforms (cGST were surveyed in three bivalves with different habitats and life strategies: Corbicula fluminea, Anodonta cygnea and Mytilus galloprovincialis. GSTs were purified by glutathione-agarose affinity chromatography, and the collection of expressed cGST classes of each bivalve were identified using a proteomic approach. All the purified extracts were also characterized kinetically. Results reveal variations in cGST subunits collection (diversity and properties between the three tested bivalves. Using proteomics, four pi-class and two sigma-class GST subunits were identified in M. galloprovincialis. C. fluminea also yielded four pi-class and one sigma-class GST subunits. For A. cygnea, two mu-class and one pi-class GST subunits were identified, these being the first record of GSTs from these freshwater mussels. The affinity purified extracts also show differences regarding enzymatic behavior among species. The variations found in cGST collection and kinetics might justify diverse selective advantages for each bivalve organism.

  20. Cloning and characterization of a glutathione S-transferase homologue from the plant pathogenic fungus Botrytis cinerea

    NARCIS (Netherlands)

    Prins, T.W.; Wagemakers, L.; Schouten, A.; Kan, van J.A.L.

    2000-01-01

    A gene was cloned from Botrytis cinerea that encodes a protein homologous to glutathione S-transferase (GST). The gene, denominated Bcgst1, is present in a single copy and represents the first example of such a gene from a filamentous fungus. The biochemical function of GSTs is to conjugate toxic

  1. Effects of curcumin on cytochrome P450 and glutathione S-transferase activities in rat liver.

    NARCIS (Netherlands)

    Oetari, S.; Sudibyo, M.; Commandeur, J.N.M.; Samhoedi, R.; Vermeulen, N.P.E.

    1996-01-01

    The stability of curcumin, as well as the interactions between curcumin and cytochrome P450s (P450s) and glutathione S-transferases (GSTs) in rat liver, were studied. Curcumin is relatively unstable in phosphate buffer at pH 7.4. The stability of curcumin was strongly improved by lowering the pH or

  2. A novel method for screening the glutathione transferase inhibitors

    Directory of Open Access Journals (Sweden)

    Węgrzyn Grzegorz

    2009-03-01

    Full Text Available Abstract Background Glutathione transferases (GSTs belong to the family of Phase II detoxification enzymes. GSTs catalyze the conjugation of glutathione to different endogenous and exogenous electrophilic compounds. Over-expression of GSTs was demonstrated in a number of different human cancer cells. It has been found that the resistance to many anticancer chemotherapeutics is directly correlated with the over-expression of GSTs. Therefore, it appears to be important to find new GST inhibitors to prevent the resistance of cells to anticancer drugs. In order to search for glutathione transferase (GST inhibitors, a novel method was designed. Results Our results showed that two fragments of GST, named F1 peptide (GYWKIKGLV and F2 peptide (KWRNKKFELGLEFPNL, can significantly inhibit the GST activity. When these two fragments were compared with several known potent GST inhibitors, the order of inhibition efficiency (measured in reactions with 2,4-dinitrochlorobenzene (CDNB and glutathione as substrates was determined as follows: tannic acid > cibacron blue > F2 peptide > hematin > F1 peptide > ethacrynic acid. Moreover, the F1 peptide appeared to be a noncompetitive inhibitor of the GST-catalyzed reaction, while the F2 peptide was determined as a competitive inhibitor of this reaction. Conclusion It appears that the F2 peptide can be used as a new potent specific GST inhibitor. It is proposed that the novel method, described in this report, might be useful for screening the inhibitors of not only GST but also other enzymes.

  3. Insecticide resistance and glutathione S-transferases in mosquitoes ...

    African Journals Online (AJOL)

    Mosquito glutathione S-transferases (GSTs) have received considerable attention in the last 20 years because of their role in insecticide metabolism producing resistance. Many different compounds, including toxic xenobiotics and reactive products of intracellular processes such as lipid peroxidation, act as GST substrates.

  4. Purification, molecular cloning and heterologous expression of a glutathione S-transferase involved in insecticide resistance from the rice brown planthopper, Nilaparvata lugens.

    Science.gov (United States)

    Vontas, John G; Small, Graham J; Nikou, Dimitra C; Ranson, Hilary; Hemingway, Janet

    2002-03-01

    A novel glutathione S-transferase (GST)-based pyrethroid resistance mechanism was recently identified in Nilaparvata lugens [Vontas, Small and Hemingway (2001) Biochem. J. 357, 65-72]. To determine the nature of GSTs involved in conferring this resistance, the GSTs from resistant and susceptible strains of N. lugens were partially purified by anion exchange and affinity chromatography. The majority of peroxidase activity, previously correlated with resistance, was confined to the fraction that bound to the affinity column, which was considerably elevated in the resistant insects. A cDNA clone encoding a GST (nlgst1-1) - the first reported GST sequence from Hemiptera with up to 54% deduced amino-acid identity with other insect class I GSTs - was isolated from a pyrethroid-resistant strain. Northern analysis showed that nlgst1-1 was overexpressed in resistant insects. nlgst1-1 was expressed in Escherichia coli, purified and characterized. The ability of the recombinant protein to bind to the S-hexylglutathione affinity matrix, its substrate specificities and its immunological properties confirmed that this GST was one from the elevated subset of N. lugens GSTs. Peroxidase activity of the recombinant nlgst1-1 indicated that it had a role in resistance, through detoxification of lipid peroxidation products induced by pyrethroids. Southern analysis of genomic DNA from the resistant and susceptible strains indicated that GST-based insecticide resistance may be associated with gene amplification in N. lugens.

  5. The effects of mutating Tyr9 and Arg15 on the structure, stability, conformational dynamics and mechanism of GSTA3-3

    CSIR Research Space (South Africa)

    Robertson, GJ

    2017-03-01

    Full Text Available activity of the steroid isomerase reaction; however, Arg15 is more important for lowering the pKa of GSH. Lowering the pKa of GSH being how GSTs catalyse their reactions. Additionally, there is evidence to suggest that Arg15 is integral to allowingGSTA3...

  6. Improving the redistribution of the security lessons in healthcare: An evaluation of the Generic Security Template.

    Science.gov (United States)

    He, Ying; Johnson, Chris

    2015-11-01

    The recurrence of past security breaches in healthcare showed that lessons had not been effectively learned across different healthcare organisations. Recent studies have identified the need to improve learning from incidents and to share security knowledge to prevent future attacks. Generic Security Templates (GSTs) have been proposed to facilitate this knowledge transfer. The objective of this paper is to evaluate whether potential users in healthcare organisations can exploit the GST technique to share lessons learned from security incidents. We conducted a series of case studies to evaluate GSTs. In particular, we used a GST for a security incident in the US Veterans' Affairs Administration to explore whether security lessons could be applied in a very different Chinese healthcare organisation. The results showed that Chinese security professional accepted the use of GSTs and that cyber security lessons could be transferred to a Chinese healthcare organisation using this approach. The users also identified the weaknesses and strengths of GSTs, providing suggestions for future improvements. Generic Security Templates can be used to redistribute lessons learned from security incidents. Sharing cyber security lessons helps organisations consider their own practices and assess whether applicable security standards address concerns raised in previous breaches in other countries. The experience gained from this study provides the basis for future work in conducting similar studies in other healthcare organisations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Implementing a High School Level Geospatial Technologies and Spatial Thinking Course

    Science.gov (United States)

    Nielsen, Curtis P.; Oberle, Alex; Sugumaran, Ramanathan

    2011-01-01

    Understanding geospatial technologies (GSTs) and spatial thinking is increasingly vital to contemporary life including common activities and hobbies; learning in science, mathematics, and social science; and employment within fields as diverse as engineering, health, business, and planning. As such, there is a need for a stand-alone K-12…

  8. 26 CFR 26.2642-5 - Finality of inclusion ratio.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 14 2010-04-01 2010-04-01 false Finality of inclusion ratio. 26.2642-5 Section...-5 Finality of inclusion ratio. (a) Direct skips. The inclusion ratio applicable to a direct skip...) Other GSTs. With respect to taxable distributions and taxable terminations, the inclusion ratio for a...

  9. Identification and expression profiles of nine glutathione S-transferase genes from the important rice phloem sap-sucker and virus vector Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae).

    Science.gov (United States)

    Zhou, Wen-Wu; Li, Xi-Wang; Quan, Yin-Hua; Cheng, Jiaan; Zhang, Chuan-Xi; Gurr, Geoff; Zhu, Zeng-Rong

    2012-09-01

    Glutathione S-transferases (GSTs) have received considerable attention in insects for their roles in insecticide resistance. Laodelphax striatellus (Fallén) is a serious rice pest. L. striatellus outbreaks occur frequently throughout eastern Asia. A key problem in controlling this pest is its rapid adaptation to numerous insecticides. In this research, nine cDNAs encoding GSTs in L. striatellus were cloned and characterised. The cloned GSTs of L. striatellus belonged to six cytosolic classes and a microsomal subgroup. Exposure to sublethal concentrations of each of the six insecticides, DDT, chlorpyrifos, fipronil, imidacloprid, buprofezin and beta-cypermethrin, quickly induced (6 h) up-expression of LsGSTe1. The expression of LsGSTs2 was increased by chlorpyrifos, fipronil and beta-cypermethrin. Furthermore, exposure of L. striatellus to fipronil, imidacloprid, buprofezin and beta-cypermethrin increased the expression of the LsGSTm gene after 24 or 48 h. This work is the first identification of GST genes from different GST groups in Auchenorrhyncha species and their induction characteristics with insecticide types and time. The elevated expression of GST genes induced by insecticides might be related to the enhanced tolerance of this insect to insecticides and xenobiotics. Copyright © 2012 Society of Chemical Industry.

  10. Antioxidant and chemoprotective properties of Momordica charantia ...

    African Journals Online (AJOL)

    We have studied the effect of M. charantia, collected from Kazdaglari (Mount Ida) in Balikesir, fruit extract on glutathione S-transferases (GSTs), cytochrome P450s (CYPs), and antioxidant enzymes in rats. Male Wistar rats, aged 12 weeks and weighing 200-250 g, were given 200 mg M. charantia fruit extract per kg body ...

  11. Differential transcription of cytochrome P450s and glutathione S transferases in DDT-susceptible and resistant Drosophila melanogaster strains in response to DDT and oxidative stress

    Science.gov (United States)

    Metabolic DDT resistance in Drosophila melanogaster has previously been associated with constitutive over-transcription of cytochrome P450s. Increased P450 activity has also been associated with increased oxidative stress. In contrast, over-transcription of glutathione S transferases (GSTs) has been...

  12. Cantharidin Impedes Activity of Glutathione S-Transferase in the Midgut of Helicoverpa armigera Hübner

    Directory of Open Access Journals (Sweden)

    Ya Lin Zhang

    2013-03-01

    Full Text Available Previous investigations have implicated glutathione S-transferases (GSTs as one of the major reasons for insecticide resistance. Therefore, effectiveness of new candidate compounds depends on their ability to inhibit GSTs to prevent metabolic detoxification by insects. Cantharidin, a terpenoid compound of insect origin, has been developed as a bio-pesticide in China, and proves highly toxic to a wide range of insects, especially lepidopteran. In the present study, we test cantharidin as a model compound for its toxicity, effects on the mRNA transcription of a model Helicoverpa armigera glutathione S-transferase gene (HaGST and also for its putative inhibitory effect on the catalytic activity of GSTs, both in vivo and in vitro in Helicoverpa armigera, employing molecular and biochemical methods. Bioassay results showed that cantharidin was highly toxic to H. armigera. Real-time qPCR showed down-regulation of the HaGST at the mRNA transcript ranging from 2.5 to 12.5 folds while biochemical assays showed in vivo inhibition of GSTs in midgut and in vitro inhibition of rHaGST. Binding of cantharidin to HaGST was rationalized by homology and molecular docking simulations using a model GST (1PN9 as a template structure. Molecular docking simulations also confirmed accurate docking of the cantharidin molecule to the active site of HaGST impeding its catalytic activity.

  13. Functional characterization of glutathione S-transferases associated with insecticide resistance in Tetranychus urticae

    NARCIS (Netherlands)

    Pavlidi, N.; Tseliou, V.; Riga, M.; Nauen, R.; Van Leeuwen, T.; Labrou, N.E.; Vontas, J.

    2015-01-01

    The two-spotted spider mite Tetranychus urticae is one of the most important agricultural pests world-wide. It is extremely polyphagous and develops resistance to acaricides. The overexpression of several glutathione S-transferases (GSTs) has been associated with insecticide resistance. Here, we

  14. Predicción computacional de la estructura terciaria de la iduronato 2-sulfato sulfatasa humana

    Directory of Open Access Journals (Sweden)

    Homero Sáenz

    2007-03-01

    Conclusión. Los valores de RMS y la correlación genotipo-fenotipo en los pacientes analizados sugieren el modelo puede usarse para predecir ciertos aspectos del comportamiento biológico de la enzima.

  15. PREDICCIÓN DE LA ESTRUCTURA Y CARACTERÍSTICAS BIOQUÍMICAS DE LA ACETATO TIOQUINASA

    Directory of Open Access Journals (Sweden)

    Jairo A. Tovart

    2001-12-01

    Full Text Available Las actividades de las enzimas implicadas en el metabolismo de los cuerpos cetónicos están presentes tanto en neuronas, como en astrocitos y en oligodendroglía. La utilización de cultivos primarios ha puesto de manifiesto que estos cuerpos cetónicos pueden ser metabolizados en estas células.La· acetato tioquinasa reportada en tejido neural total es una enzima que reduce significativamente el costo energético de la utilización del acetato y por lo tanto se propone como una ruta de elección en metabolismo de esta sustancia.Los datos de predicción para propiedades bioquímicas y estructurales de la enzima muestran una estructura estable, con segmentos conservados entre todas las secuencias existentes y una alta flexibilidad estructural, propia de la mayoría de la enzimas.

  16. Phylogenetic characterization of Clonorchis sinensis proteins homologous to the sigma-class glutathione transferase and their differential expression profiles.

    Science.gov (United States)

    Bae, Young-An; Kim, Jeong-Geun; Kong, Yoon

    2016-01-01

    Glutathione transferase (GST) is one of the major antioxidant proteins with diverse supplemental activities including peroxidase, isomerase, and thiol transferase. GSTs are classified into multiple classes on the basis of their primary structures and substrate/inhibitor specificity. However, the evolutionary routes and physiological environments specific to each of the closely related bioactive enzymes remain elusive. The sigma-like GSTs exhibit amino acid conservation patterns similar to the prostaglandin D synthases (PGDSs). In this study, we analyzed the phylogenetic position of the GSTs of the biocarcinogenic liver fluke, Clonorchis sinensis. We also observed induction profile of the GSTs in association with the parasite's maturation and in response to exogenous oxidative stresses, with special attention to sigma-class GSTs and PGDSs. The C. sinensis genome encoded 12 GST protein species, which were separately assigned to cytosolic (two omega-, one zeta-, two mu-, and five sigma-class), mitochondrial (one kappa-class), and microsomal (one membrane-associated proteins in eicosanoid and glutathione metabolism-like protein) GST families. Multiple sigma GST (or PGDS) orthologs were also detected in Opisthorchis viverrini. Other trematode species possessed only a single sigma-like GST gene. A phylogenetic analysis demonstrated that one of the sigma GST lineages duplicated in the common ancestor of trematodes were specifically expanded in the opisthorchiids, but deleted in other trematodes. The induction profiles of these sigma GST genes along with the development and aging of C. sinensis, and against various exogenous chemical stimuli strongly suggest that the paralogous sigma GST genes might be undergone specialized evolution to cope with the diverse hostile biochemical environments within the mammalian hepatobiliary ductal system. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Glutathione-S-transferase profiles in the emerald ash borer, Agrilus planipennis.

    Science.gov (United States)

    Rajarapu, Swapna Priya; Mittapalli, Omprakash

    2013-05-01

    The emerald ash borer, Agrilus planipennis Fairmaire is a recently discovered invasive insect pest of ash, Fraxinus spp. in North America. Glutathione-S-transferases (GST) are a multifunctional superfamily of enzymes which function in conjugating toxic compounds to less toxic and excretable forms. In this study, we report the molecular characterization and expression patterns of different classes of GST genes in different tissues and developmental stages plus their specific activity. Multiple sequence alignment of all six A. planipennis GSTs (ApGST-E1, ApGST-E2, ApGST-E3, ApGST-O1, ApGST-S1 and ApGST-μ1) revealed conserved features of insect GSTs and a phylogenetic analysis grouped the GSTs within the epsilon, sigma, omega and microsomal classes of GSTs. Real time quantitative PCR was used to study field collected samples. In larval tissues high mRNA levels for ApGST-E1, ApGST-E3 and ApGST-O1 were obtained in the midgut and Malpighian tubules. On the other hand, ApGST-E2 and ApGST-S1 showed high mRNA levels in fat body and ApGST-μ1 showed constitutive levels in all the tissues assayed. During development, mRNA levels for ApGST-E2 were observed to be the highest in feeding instars, ApGST-S1 in prepupal instars; while the others showed constitutive patterns in all the developmental stages examined. At the enzyme level, total GST activity was similar in all the tissues and developmental stages assayed. Results obtained suggest that A. planipennis is potentially primed with GST-driven detoxification to metabolize ash allelochemicals. To our knowledge this study represents the first report of GSTs in A. planipennis and also in the family of wood boring beetles. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Relationship of socio-economic status and childhood cancer: an in ...

    African Journals Online (AJOL)

    2017-11-30

    Nov 30, 2017 ... Social and economic factors are known to affect health and well-being in several ... -seeking attitudes in childhood cancer; this usually re- sults in late ..... reported in guardians of 5.0% in Kenya and 19% in. Uganda.20 This ...

  19. Fulltext PDF

    Indian Academy of Sciences (India)

    Admin

    So you should expect to ¯nd,say,a certain kind of duck on one ... w as beaten by a great m any people on various notions like the tree of ... sults that I think he w as truly original in are: 1. ..... appealing to `forerunners', heroic and successful, one.

  20. l04------------------------------~------------RESONANCEI--N-ov-ember--19 ...

    Indian Academy of Sciences (India)

    Needless to say, I strongly recom- mend that all students of mathematics read this book. For the lay person, this is an excellent exposure to mathematics. For the undergraduate student this book serves as an introduction to many beautiful re- sults in mathematics and also an opportu- nity to learn about the rich history and.

  1. Matrix-derived combination effect and risk assessment for estragole from basil-containing plant food supplements (PFS)

    NARCIS (Netherlands)

    Berg, van den S.J.P.L.; Klaus, V.; Alhusainy, W.; Rietjens, I.

    2013-01-01

    Basil-containing plant food supplements (PFS) can contain estragole which can be metabolised into a genotoxic and carcinogenic 1'-sulfoxymetabolite. This study describes the inhibition of sulfotransferase (SULT)-mediated bioactivation of estragole by compounds present in basil-containing PFS.

  2. Mitigation of Shore Damage Attributed to the Federal Navigation Structures at Port Sanilac Harbor, Michigan.

    Science.gov (United States)

    1975-09-01

    produces waves with nealioible wace heights (i.e., 0.5 feet); (b) all waves were deep water waves with no correction for shallow water; and, (c) the...at that harbor. This would re- sult in a loss to the local economy . Ini addition, littoral drift would resume southward thus affecting the littoral

  3. Low Cost Technical Solutions to Jump Start an Insider Threat Program

    Science.gov (United States)

    2016-05-11

    from the OpenDLP server. The OpenDLP server manages the re- sults of the scans. OpenDLP also has the ability to scan Microsoft SQL Server and MySQL data...Learning Group at the University of Waikato, "Weka 3: Data Mining Software in Java ," [Online]. Available: http://www.cs.waikato.ac.nz/ml/weka

  4. The Coast Artillery Journal. Volume 75, Number 2, March-April 1932

    Science.gov (United States)

    1932-04-01

    after three years’ study of the Japanese language-study which has re- sulted not in my gaining easy fluency in the language of the Samurai but in...eight and a half feet thick, using 850 pounds of cement to ite cubic yard. In standard European fortifications the proportion of cement to the cubic yard

  5. evaluation of a modified passive solar housing system for poultry

    African Journals Online (AJOL)

    User

    The hourly efficiency of the solar brick passive system was estimated at about 78.42% in a day of May and ... to high cost and unavailability of kerosene in most developing .... sulted in intermittent rainfall, cloud cover and sunshine. From the ...

  6. Forfatteren som eksperimentator

    DEFF Research Database (Denmark)

    Hedin, Gry

    2011-01-01

    Det kan overraske, at man i Hamsun-forskningen ikke har skænket den første version af Sult mere opmærksomhed. Hamsuns publicering i tidsskriftet Ny Jord af det, der skulle blive bogens andet stykke, er med enkelte undtagelser overset i forskningen. En analyse af teksten og dens kontekst kan imidl...

  7. An action-learning model to assist Circuit Teams to support School ...

    African Journals Online (AJOL)

    EAOSA

    2016-11-17

    Nov 17, 2016 ... If the role of the Education District and Circuit Officers in South Africa is to work collaboratively with schools to improve educational ..... sulted in the Chief Curriculum Advisor not allowing ..... 2008/09 financial year. Zwelitsha ...

  8. Selective activation around the left occipito-temporal sulcus for words relative to pictures: Individual variability or false positives?

    NARCIS (Netherlands)

    Wright, Nicholas D.; Mechelli, Andrea; Noppeney, Uta; Veltman, Dick J.; Rombouts, Serge A. R. B.; Glensman, Janice; Haynes, John-Dylan; Price, Cathy J.

    2008-01-01

    We used high-resolution fMRI to investigate claims that learning to read r !sults in greater left occipito-temporal (OT) activation for written words relative to pictures of objects. In tl e first experiment, 9/16 subjects performing a one-back task showed activation in >= 1 left OT voxel for word:

  9. Notre Continent, Notre Avenir: Perspectives africaines sur l ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    On ne sait pas très bien si la non-application effective résulte du refus ...... La main-d'œuvre est moins mobile au plan international que le capital, et donc ...... Auty, R., 1995, « Economic development and the resource curse thesis », dans ...

  10. Dgroup: DG02549 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available DG02549 Chemical ... DGroup Rotigotine ... D05768 ... Rotigotine (JAN/USAN/INN) ... ATC code: N04BC09 Antiparkinson...ian, Dopamine D2 receptor agonist DRD2 [HSA:1813] [KO:K04145] Enzyme: SULT1A1 [HSA:

  11. Image Analysis and Modeling

    Science.gov (United States)

    1975-05-01

    place "subgraphs" with more complicated subgraphs. There have beer many re- sults reported which extend string-grammar theorems to web grammar...W. Bacus and E. E. Gose , "Leukocyte Pattern Recognition," IEEE SMC-2. No. 2, pp. 513-536, September 1972. [4] J. K. Hawkins

  12. Theoretical Modeling of Ultrashot Laser Pulse Interaction With Dielectric and Semiconductor Materials

    Science.gov (United States)

    2010-05-24

    of linearly polarized electromagnetic radiation re- sults in an anisotropic electronic transition rate characterized by field dependence via a Bessel...where Ω ( ~k, ~r ) is the renormalized Rabi frequency defined by: ~Ω ( ~k, ~r ) = µ ( ~k ) ~E (~r, t) + ∑ ~k′ p ( ~k′, ~r ) V s~k−~k′ . (12) The second

  13. Identification of Mutations in SDR9C7 in 6 Families with Autosomal Recessive Congenital Ichthyosis

    DEFF Research Database (Denmark)

    Hotz, A; Fagerberg, C; Vahlquist, A

    2018-01-01

    Autosomal recessive congenital ichthyosis (ARCI) is a heterogeneous group of disorders of keratinization. To date, ARCI has been associated with following genes: ABCA12, ALOX12B, ALOXE3, CERS3, CYP4F22, NIPAL4, TGM1, PNPLA1 and recently SDR9C7 and SULT2B1.(1-6) Furthermore, seven patients from...

  14. Using FML and fuzzy technology in adaptive ambient intelligent environments

    NARCIS (Netherlands)

    Acampora, G.; Loia, V.

    2005-01-01

    Ambient Intelligence (AmI, shortly) gathers best re-sults from three key technologies, Ubiquitous Computing, Ubiq-uitous Communication, and Intelligent User Friendly Inter-faces. The functional and spatial distribution of tasks is a natu-ral thrust to employ multi-agent paradigm to design and

  15. Parallelization of TMVA Machine Learning Algorithms

    CERN Document Server

    Hajili, Mammad

    2017-01-01

    This report reflects my work on Parallelization of TMVA Machine Learning Algorithms integrated to ROOT Data Analysis Framework during summer internship at CERN. The report consists of 4 impor- tant part - data set used in training and validation, algorithms that multiprocessing applied on them, parallelization techniques and re- sults of execution time changes due to number of workers.

  16. Permanent neonatal diabetes mellitus - a case report of a rare cause ...

    African Journals Online (AJOL)

    sulting from a mutation in the KCNJ11 gene encoding the Kir6.2 subunit. Despite the rarity of permanent neonatal diabetes, this diagnosis should be considered in infants with persis- tent hyperglycaemia requiring insulin therapy. Children with an ATP-sensitive potassium channel defect in the pancreatic beta cell have an ...

  17. Two new polyoxovanadate clusters templated through cysteamine

    Indian Academy of Sciences (India)

    Unknown

    variably formed.6–10 These may be salts between organic cations and discrete ... Vanadium pentoxide (V2O5), sodium hydroxide. (NaOH) and cysteamine were .... sulting in 2D layers and other nitrogen (N1) forming. H-bonding to one water ...

  18. Some Elementary Examples from Newton's Principia -R-ES ...

    Indian Academy of Sciences (India)

    ing both differential and integral calculus. Newton used many geometrical methods extensively to derive the re- sults in spite of his having discovered calculus. Geome- try, judiciously used with limiting procedures, was one principal strategy used by Newton in the Principia. The Principia presents an enormous range of ...

  19. The Effect of Lexicographical Information Costs on Dictionary Making and Use

    DEFF Research Database (Denmark)

    Nielsen, Sandro

    2008-01-01

    ­tinction is proposed between two general types of lexicographical information costs. Firstly, search-related costs are the efforts required by the look-up activities users have to perform when con­sulting a dictionary to find access to the data they are searching for. It is argued that the access route, article...

  20. Genetic Determinants of Gastric Cancer

    NARCIS (Netherlands)

    S. Boccia (Stefania)

    2009-01-01

    textabstractResults show that gastric cancer risk is increased by the inheritance of the variant alleles of the metabolic genes SULT1A1 and CYP2E1 *6, especially among smokers and drinkers, respectively. An additional increased risk is conferred by the inheritance of GSTT1 null variant, especially

  1. Hvordan kan man sige nej til GMO?

    DEFF Research Database (Denmark)

    Heðinsdóttir, Katla; Gjerris, Mickey

    2015-01-01

    Modstandere af genteknologi udtrykker ofte deres bekymring med, at teknologien er “unaturlig”. Men hvad mener de egentlig med det? Og er det et synspunkt, der skal tages seriøst, hvis genmodificering af fødevarevarer kan være med til at eliminere sult og fejlernæring i verden?...

  2. The influence of farmer perception on pesticide usage for ...

    African Journals Online (AJOL)

    A case study conducted in eastern Uganda revealed that: (a) pesticide usage depended on farmer production goal, (b) change from one pesticide to another depended on ... Ces résults ont fermément montré que les recommendations de la gestion des pestes aux fermiers doivent prendre en considération la perception des ...

  3. Navodnenija v umah zactroishtshikov / Maris Kuuda

    Index Scriptorium Estoniae

    Kuuda, Maris

    2007-01-01

    Kohalikel omavalitsustel pole piisavalt hoobasid sundida arendajaid üleujutusohuga arvestama. Pärnusse hotelli September rajajad (arhitektid Emil Urbel, Andrus Mark) arvestavad ujutusohuga. Arvamust avaldavad Rene Reisner, Mari Sepp, Ülo Sults, Karri Tiigisoon, Indrek Rannik, Mark Soosaar, Tiiu Pärn, Merle Looring, Rita Sepp, Kaspar Alles

  4. Humanizing π-class glutathione S-transferase regulation in a mouse model alters liver toxicity in response to acetaminophen overdose.

    Directory of Open Access Journals (Sweden)

    Matthew P Vaughn

    Full Text Available Glutathione S-transferases (GSTs metabolize drugs and xenobiotics. Yet despite high protein sequence homology, expression of π-class GSTs, the most abundant of the enzymes, varies significantly between species. In mouse liver, hepatocytes exhibit high mGstp expression, while in human liver, hepatocytes contain little or no hGSTP1 mRNA or hGSTP1 protein. π-class GSTs are known to be critical determinants of liver responses to drugs and toxins: when treated with high doses of acetaminophen, mGstp1/2+/+ mice suffer marked liver damage, while mGstp1/2-/- mice escape liver injury.To more faithfully model the contribution of π-class GSTs to human liver toxicology, we introduced hGSTP1, with its exons, introns, and flanking sequences, into the germline of mice carrying disrupted mGstp genes. In the resultant hGSTP1+mGstp1/2-/- strain, π-class GSTs were regulated differently than in wild-type mice. In the liver, enzyme expression was restricted to bile duct cells, Kupffer cells, macrophages, and endothelial cells, reminiscent of human liver, while in the prostate, enzyme production was limited to basal epithelial cells, reminiscent of human prostate. The human patterns of hGSTP1 transgene regulation were accompanied by human patterns of DNA methylation, with bisulfite genomic sequencing revealing establishment of an unmethylated CpG island sequence encompassing the gene promoter. Unlike wild-type or mGstp1/2-/- mice, when hGSTP1+mGstp1/2-/- mice were overdosed with acetaminophen, liver tissues showed limited centrilobular necrosis, suggesting that π-class GSTs may be critical determinants of toxin-induced hepatocyte injury even when not expressed by hepatocytes.By recapitulating human π-class GST expression, hGSTP1+mGstp1/2-/- mice may better model human drug and xenobiotic toxicology.

  5. Effect of resveratrol on 17beta-estradiol sulfation by human hepatic and jejunal S9 and recombinant sulfotransferase 1E1.

    Science.gov (United States)

    Furimsky, Anna M; Green, Carol E; Sharp, Lewanne E Hunt; Catz, Paul; Adjei, Araba A; Parman, Toufan; Kapetanovic, Izet M; Weinshilboum, Richard M; Iyer, Lalitha V

    2008-01-01

    The purpose of this study was to investigate the sulfation of resveratrol (3,5,4'-trihydroxystilbene) and its potential to exhibit drug-drug interactions via sulfation. The possible interaction of resveratrol with 17beta-estradiol (E2), a major estrogen hormone and prototypic substrate for sulfate conjugation, was studied. Resveratrol and E2 are both known to undergo sulfate conjugation catalyzed by human sulfotransferases (SULTs). Resveratrol is a phytoestrogen with mixed estrogen agonist/antagonist properties that is being developed as a chemopreventive agent. The sulfate conjugation of E2 and resveratrol were studied individually using S9 fractions from human liver and jejunum as well as recombinant human SULT isoforms. The sulfation of E2 (3-20 nM) was then investigated in the presence of various concentrations (0, 0.5, 1, and 2 microM) of resveratrol using the two S9 preparations as well as recombinant SULT1E1, the major isoform responsible for E2 sulfation. Resveratrol inhibited E2 sulfation with estimated K(i) values of 1.1 microM (liver), 0.6 microM (jejunum), and 2.3 microM (SULT1E1), concentrations that could be pharmacologically relevant. The results suggest that these phytoestrogens can potentially alter the homeostasis of estrogen levels. These findings also imply that resveratrol may inhibit the metabolism of other estrogen analogs or therapeutic agents such as ethinylestradiol or dietary components that are also substrates for SULT1E1.

  6. Epistasis Analysis for Estrogen Metabolic and Signaling Pathway Genes on Young Ischemic Stroke Patients

    Science.gov (United States)

    Hsieh, Yi-Chen; Jeng, Jiann-Shing; Lin, Huey-Juan; Hu, Chaur-Jong; Yu, Chia-Chen; Lien, Li-Ming; Peng, Giia-Sheun; Chen, Chin-I; Tang, Sung-Chun; Chi, Nai-Fang; Tseng, Hung-Pin; Chern, Chang-Ming; Hsieh, Fang-I; Bai, Chyi-Huey; Chen, Yi-Rhu; Chiou, Hung-Yi; Jeng, Jiann-Shing; Tang, Sung-Chun; Yeh, Shin-Joe; Tsai, Li-Kai; Kong, Shin; Lien, Li-Ming; Chiu, Hou-Chang; Chen, Wei-Hung; Bai, Chyi-Huey; Huang, Tzu-Hsuan; Chi-Ieong, Lau; Wu, Ya-Ying; Yuan, Rey-Yue; Hu, Chaur-Jong; Sheu, Jau- Jiuan; Yu, Jia-Ming; Ho, Chun-Sum; Chen, Chin-I; Sung, Jia-Ying; Weng, Hsing-Yu; Han, Yu-Hsuan; Huang, Chun-Ping; Chung, Wen-Ting; Ke, Der-Shin; Lin, Huey-Juan; Chang, Chia-Yu; Yeh, Poh-Shiow; Lin, Kao-Chang; Cheng, Tain-Junn; Chou, Chih-Ho; Yang, Chun-Ming; Peng, Giia-Sheun; Lin, Jiann-Chyun; Hsu, Yaw-Don; Denq, Jong-Chyou; Lee, Jiunn-Tay; Hsu, Chang-Hung; Lin, Chun-Chieh; Yen, Che-Hung; Cheng, Chun-An; Sung, Yueh-Feng; Chen, Yuan-Liang; Lien, Ming-Tung; Chou, Chung-Hsing; Liu, Chia-Chen; Yang, Fu-Chi; Wu, Yi-Chung; Tso, An-Chen; Lai, Yu- Hua; Chiang, Chun-I; Tsai, Chia-Kuang; Liu, Meng-Ta; Lin, Ying-Che; Hsu, Yu-Chuan; Chen, Chih-Hung; Sung, Pi-Shan; Chern, Chang-Ming; Hu, Han-Hwa; Wong, Wen-Jang; Luk, Yun-On; Hsu, Li-Chi; Chung, Chih-Ping; Tseng, Hung-Pin; Liu, Chin-Hsiung; Lin, Chun-Liang; Lin, Hung-Chih; Hu, Chaur-Jong

    2012-01-01

    Background Endogenous estrogens play an important role in the overall cardiocirculatory system. However, there are no studies exploring the hormone metabolism and signaling pathway genes together on ischemic stroke, including sulfotransferase family 1E (SULT1E1), catechol-O-methyl-transferase (COMT), and estrogen receptor α (ESR1). Methods A case-control study was conducted on 305 young ischemic stroke subjects aged ≦ 50 years and 309 age-matched healthy controls. SULT1E1 -64G/A, COMT Val158Met, ESR1 c.454−397 T/C and c.454−351 A/G genes were genotyped and compared between cases and controls to identify single nucleotide polymorphisms associated with ischemic stroke susceptibility. Gene-gene interaction effects were analyzed using entropy-based multifactor dimensionality reduction (MDR), classification and regression tree (CART), and traditional multiple regression models. Results COMT Val158Met polymorphism showed a significant association with susceptibility of young ischemic stroke among females. There was a two-way interaction between SULT1E1 -64G/A and COMT Val158Met in both MDR and CART analysis. The logistic regression model also showed there was a significant interaction effect between SULT1E1 -64G/A and COMT Val158Met on ischemic stroke of the young (P for interaction = 0.0171). We further found that lower estradiol level could increase the risk of young ischemic stroke for those who carry either SULT1E1 or COMT risk genotypes, showing a significant interaction effect (P for interaction = 0.0174). Conclusions Our findings support that a significant epistasis effect exists among estrogen metabolic and signaling pathway genes and gene-environment interactions on young ischemic stroke subjects. PMID:23112845

  7. Genotype of metabolic enzymes and the benefit of tamoxifen in postmenopausal breast cancer patients

    International Nuclear Information System (INIS)

    Wegman, Pia; Vainikka, Linda; Stål, Olle; Nordenskjöld, Bo; Skoog, Lambert; Rutqvist, Lars-Erik; Wingren, Sten

    2005-01-01

    Tamoxifen is widely used as endocrine therapy for oestrogen-receptor-positive breast cancer. However, many of these patients experience recurrence despite tamoxifen therapy by incompletely understood mechanisms. In the present report we propose that tamoxifen resistance may be due to differences in activity of metabolic enzymes as a result of genetic polymorphism. Cytochrome P450 2D6 (CYP2D6) and sulfotransferase 1A1 (SULT1A1) are polymorphic and are involved in the metabolism of tamoxifen. The CYP2D6*4 and SULT1A1*2 genotypes result in decreased enzyme activity. We therefore investigated the genotypes of CYP2D6 and SULT1A1 in 226 breast cancer patients participating in a trial of adjuvant tamoxifen treatment in order to validate the benefit from the therapy. The patients were genotyped using PCR followed by cleavage with restriction enzymes. Carriers of the CYP2D6*4 allele demonstrated a decreased risk of recurrence when treated with tamoxifen (relative risk = 0.28, 95% confidence interval = 0.11–0.74, P = 0.0089). A similar pattern was seen among the SULT1A1*1 homozygotes (relative risk = 0.48, 95% confidence interval = 0.21–1.12, P = 0.074). The combination of CYP2D6*4 and/or SULT1A1*1/*1 genotypes comprised 60% of the patients and showed a 62% decreased risk of distant recurrence with tamoxifen (relative risk = 0.38, 95% confidence interval = 0.19–0.74, P = 0.0041). The present study suggests that genotype of metabolic enzymes might be useful as a guide for adjuvant endocrine treatment of postmenopausal breast cancer patients. However, results are in contradiction to prior hypotheses and the present sample size is relatively small. Findings therefore need to be confirmed in a larger cohort

  8. Phi Class of Glutathione S-transferase Gene Superfamily Widely Exists in Nonplant Taxonomic Groups.

    Science.gov (United States)

    Munyampundu, Jean-Pierre; Xu, You-Ping; Cai, Xin-Zhong

    2016-01-01

    Glutathione S-transferases (GSTs) constitute a superfamily of enzymes involved in detoxification of noxious compounds and protection against oxidative damage. GST class Phi (GSTF), one of the important classes of plant GSTs, has long been considered as plant specific but was recently found in basidiomycete fungi. However, the range of nonplant taxonomic groups containing GSTFs remains unknown. In this study, the distribution and phylogenetic relationships of nonplant GSTFs were investigated. We identified GSTFs in ascomycete fungi, myxobacteria, and protists Naegleria gruberi and Aureococcus anophagefferens. GSTF occurrence in these bacteria and protists correlated with their genome sizes and habitats. While this link was missing across ascomycetes, the distribution and abundance of GSTFs among ascomycete genomes could be associated with their lifestyles to some extent. Sequence comparison, gene structure, and phylogenetic analyses indicated divergence among nonplant GSTFs, suggesting polyphyletic origins during evolution. Furthermore, in silico prediction of functional partners suggested functional diversification among nonplant GSTFs.

  9. Isolation and characterization of a cDNA clone coding for a glutathione S-transferase class delta enzyme from the biting midge Culicoides variipennis sonorensis Wirth and Jones.

    Science.gov (United States)

    Abdallah, M A; Pollenz, R S; Droog, F N; Nunamaker, R A; Tabachnick, W J; Murphy, K E

    2000-12-01

    Culicoides variipennis sonorensis is the primary vector of bluetongue viruses in North America. Glutathione S-transferases (GSTs) are enzymes that catalyze nucleophilic substitutions, converting reactive lipophilic molecules into soluble conjugates. Increased GST activity is associated with development of insecticide resistance. Described here is the isolation of the first cDNA encoding a C. variipennis GST. The clone consists of 720 translated bases encoding a protein with a M(r) of approximately 24,800 composed of 219 amino acids. The deduced amino acid sequence is similar (64%-74%) to class Delta (previously named Theta) GSTs from the dipteran genera Musca, Drosophila, Lucilia and Anopheles. The cDNA was subcloned into pET-11b, expressed in Epicurian coli BL21 (DE3) and has a specific activity of approximately 28,000 units/mg for the substrate 1-chloro-2,4-dinitrobenzene.

  10. Isolation and purification of glutathione S-transferases from Brachionus plicatilis and B. calyciflorus (Rotifera).

    Science.gov (United States)

    Bowman, B P; Snell, T W; Cochrane, B J

    1990-01-01

    1. The enzyme glutathione S-transferase (GST), a critical element in xenobiotic metabolism, was isolated from the marine rotifer Brachionus plicatilis and its freshwater congener B. calyciflorus. 2. In B. plicatilis, GST comprised 4.2% of cytosolic protein and was present as three separate isozymes with mol. wts 30,000, 31,400 and 33,700. Specific activity of crude homogenates was 56 nmol min-1 mg-1 protein, while that of affinity chromatography purified GST was 1850. 3. In B. calyciflorus, GST was present as two isozymes with mol. wts of 26,300 and 28,500, representing 1.0% of cytosolic protein. Crude GST specific activity was 1750 nmol min-1 mg-1 protein and purified was 72,400. 4. Rotifer GSTs are unusual because they are monomers whereas all other animals thus far investigated posses dimeric GSTs.

  11. Glutathione S-Transferase (GST Gene Diversity in the Crustacean Calanus finmarchicus--Contributors to Cellular Detoxification.

    Directory of Open Access Journals (Sweden)

    Vittoria Roncalli

    Full Text Available Detoxification is a fundamental cellular stress defense mechanism, which allows an organism to survive or even thrive in the presence of environmental toxins and/or pollutants. The glutathione S-transferase (GST superfamily is a set of enzymes involved in the detoxification process. This highly diverse protein superfamily is characterized by multiple gene duplications, with over 40 GST genes reported in some insects. However, less is known about the GST superfamily in marine organisms, including crustaceans. The availability of two de novo transcriptomes for the copepod, Calanus finmarchicus, provided an opportunity for an in depth study of the GST superfamily in a marine crustacean. The transcriptomes were searched for putative GST-encoding transcripts using known GST proteins from three arthropods as queries. The identified transcripts were then translated into proteins, analyzed for structural domains, and annotated using reciprocal BLAST analysis. Mining the two transcriptomes yielded a total of 41 predicted GST proteins belonging to the cytosolic, mitochondrial or microsomal classes. Phylogenetic analysis of the cytosolic GSTs validated their annotation into six different subclasses. The predicted proteins are likely to represent the products of distinct genes, suggesting that the diversity of GSTs in C. finmarchicus exceeds or rivals that described for insects. Analysis of relative gene expression in different developmental stages indicated low levels of GST expression in embryos, and relatively high expression in late copepodites and adult females for several cytosolic GSTs. A diverse diet and complex life history are factors that might be driving the multiplicity of GSTs in C. finmarchicus, as this copepod is commonly exposed to a variety of natural toxins. Hence, diversity in detoxification pathway proteins may well be key to their survival.

  12. Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells

    International Nuclear Information System (INIS)

    Scharmach, E.; Hessel, S.; Niemann, B.; Lampen, A.

    2009-01-01

    The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

  13. Gene expression profiling in chemoresistant variants of three cell lines of different origin

    DEFF Research Database (Denmark)

    Johnsson, Anders; Vallon-Christensson, Johan; Strand, Carina

    2005-01-01

    lines (K562 leukemia, MCF-7 breast cancer and S1 colon cancer) with acquired resistance against five cytostatic drugs; daunorubicin (DNR), doxorubicin (DOX), vincristine (VCR), etoposide (VP) and mitoxantrone (MX). RESULTS: The resistant cell lines clustered together based on their type of origin...... was also seen in, e.g., GSTs, topoisomerases, caveolins, annexins and CD44. CONCLUSION: These results will constitute a platform for further studies on specific pathways and biological processes involved in chemotherapy resistance....

  14. Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells.

    Science.gov (United States)

    Scharmach, E; Hessel, S; Niemann, B; Lampen, A

    2009-11-30

    The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

  15. A glutathione S-transferase gene associated with antioxidant properties isolated from Apis cerana cerana

    Science.gov (United States)

    Liu, Shuchang; Liu, Feng; Jia, Haihong; Yan, Yan; Wang, Hongfang; Guo, Xingqi; Xu, Baohua

    2016-06-01

    Glutathione S-transferases (GSTs) are an important family of multifunctional enzymes in aerobic organisms. They play a crucial role in the detoxification of exogenous compounds, especially insecticides, and protection against oxidative stress. Most previous studies of GSTs in insects have largely focused on their role in insecticide resistance. Here, we isolated a theta class GST gene designated AccGSTT1 from Apis cerana cerana and aimed to explore its antioxidant and antibacterial attributes. Analyses of homology and phylogenetic relationships suggested that the predicted amino acid sequence of AccGSTT1 shares a high level of identity with the other hymenopteran GSTs and that it was conserved during evolution. Quantitative real-time PCR showed that AccGSTT1 is most highly expressed in adult stages and that the expression profile of this gene is significantly altered in response to various abiotic stresses. These results were confirmed using western blot analysis. Additionally, a disc diffusion assay showed that a recombinant AccGSTT1 protein may be roughly capable of inhibiting bacterial growth and that it reduces the resistance of Escherichia coli cells to multiple adverse stresses. Taken together, these data indicate that AccGSTT1 may play an important role in antioxidant processes under adverse stress conditions.

  16. Glutathione Transferases Superfamily: Cold-Inducible Expression of Distinct GST Genes in Brassica oleracea

    Directory of Open Access Journals (Sweden)

    Harshavardhanan Vijayakumar

    2016-07-01

    Full Text Available Plants, as sessile organisms, can suffer serious growth and developmental consequences under cold stress conditions. Glutathione transferases (GSTs, EC 2.5.1.18 are ubiquitous and multifunctional conjugating proteins, which play a major role in stress responses by preventing oxidative damage by reactive oxygen species (ROS. Currently, understanding of their function(s during different biochemical and signaling pathways under cold stress condition remain unclear. In this study, using combined computational strategy, we identified 65 Brassica oleracea glutathione transferases (BoGST and characterized them based on evolutionary analysis into 11 classes. Inter-species and intra-species duplication was evident between BoGSTs and Arabidopsis GSTs. Based on localization analyses, we propose possible pathways in which GST genes are involved during cold stress. Further, expression analysis of the predicted putative functions for GST genes were investigated in two cold contrasting genotypes (cold tolerance and susceptible under cold condition, most of these genes were highly expressed at 6 h and 1 h in the cold tolerant (CT and cold susceptible (CS lines, respectively. Overall, BoGSTU19, BoGSTU24, BoGSTF10 are candidate genes highly expressed in B. oleracea. Further investigation of GST superfamily in B. oleracea will aid in understanding complex mechanism underlying cold tolerance in plants.

  17. Allyl isothiocyanate that induces GST and UGT expression confers oxidative stress resistance on C. elegans, as demonstrated by nematode biosensor.

    Directory of Open Access Journals (Sweden)

    Koichi Hasegawa

    Full Text Available BACKGROUND: Electrophilic xenobiotics and endogenous products from oxidative stresses induce the glutathione S-transferases (GSTs, which form a large family within the phase II enzymes over both animal and plant kingdoms. The GSTs thus induced in turn detoxify these external as well as internal stresses. Because these stresses are often linked to ageing and damage to health, the induction of phase II enzymes without causing adverse effects would be beneficial in slowing down ageing and keeping healthy conditions. METHODOLOGY/PRINCIPAL FINDINGS: We have tested this hypothesis by choosing allyl isothiocyanate (AITC, a functional ingredient in wasabi, as a candidate food ingredient that induces GSTs without causing adverse effects on animals' lives. To monitor the GST induction, we constructed a gst::gfp fusion gene and used it to transform Caenorhabditis elegans for use as a nematode biosensor. With the nematode biosensor, we found that AITC induced GST expression and conferred tolerance on the nematode against various oxidative stresses. We also present evidence that the transcription factor SKN-1 is involved in regulating the GST expression induced by AITC. CONCLUSIONS/SIGNIFICANCE: We show the applicability of the nematode biosensor for discovering and evaluating functional food substances and chemicals that would provide anti-ageing or healthful benefits.

  18. OBTAINING AND USE OF POLYPHENOLOXIDASE ENZYME EXTRACTED FROM RIPE CUSTARD APPLE (Annona squamosa L.) PULP ON THE COCOA (Theobroma cacao L.) NIBS IN TASTE IMPROVEMENT

    OpenAIRE

    LIMA, ELIZA DOROTEA POZZOBON DE ALBUQUERQUE; PASTORE, GLÁUCIA MARIA; BARBERY, SANDRA DRINA FERNANDEZ; GARCIA, NELSON HORÁCIO PEZOA; BRITO, EDY SOUSA DE; LIMA, CARLOS ALBERTO DE ALBUQUERQUE

    2001-01-01

    O presente trabalho teve como objetivo estudar a obtenção e a utilização da enzima polifenoloxidase (PPO) extraída de polpa de pinha madura na redução do teor de compostos polifenólicos com a finalidade de diminuir a adstringência e o amargor das amêndoas de cacau processadas na forma de "nibs". A PPO foi extraída com tampão fosfato de potássio 0,025M (pH 7,5), adicionando sulfato de amônio para a precipitação da enzima. O material em pó obtido foi denominado de enzima parcialmente purificada...

  19. PURIFICAÇÃO DA ASCORBATO-OXIDASE POR ELETROELUIÇÃO PARA DETERMINAÇÃO DE VITAMINA C

    Directory of Open Access Journals (Sweden)

    Ligia Renata FIRMINO

    2009-07-01

    Full Text Available

    O método de eletroeluição revelou-se eficiente, rápido e simples para purificar a enzima ascorbato-oxidase de abobrinha (Cucurbita pepo medulosa A atividade específica da enzima, após a eletroeluição, foi da ordem de 1.421 U/mg de proteína, obtendo-se nessa etapa um fator de purificação de 152,8 vezes. O conteúdo de vitamina C de alimentos e medicamento foi determinado com a enzima purificada e comparado com o método titulométrico que utiliza o DFI.

  20. Estudo e otimização da produção da dextranasacarase e caracterização da dextrana produzida por Leuconostoc mesenteroides FT045B

    OpenAIRE

    Vettori, Mary Helen Palmuti Braga [UNESP

    2011-01-01

    Um estudo comparativo de onze métodos para determinação da atividade da dextranasacarase e de enzimas relacionadas foi realizado. Atualmente existem dois métodos usualmente empregados na determinação da atividade da dextranasacarase. Um método relativamente difundido para a reação da enzima com a sacarose consiste na medição dos valores redutores da D-frutose pelo reagente 3,5-dinitrosalicilato (DNS). Outro método é a reação da enzima com 14Csacarose, pela adição de uma alíquota da reação em ...

  1. Enzibióticos bactericidas mejorados frente a neumococo y otras bacterias

    OpenAIRE

    García, Pedro; Menéndez, Margarita; García, Ernesto; Díez-Martínez, Roberto; De Paz, Héctor D.; Bustamante, Noemí

    2013-01-01

    La presente invención se encuadra dentro del campo de la biotecnología. En la presente invención se presenta una secuencia polipeptídica derivada del módulo de unión a pared del enzima lítica del fago Cp7 (Cpl-7), que permite la construcción de nuevas enzimas líticas con actividad bactericida mejorada y amplio espectro. Igualmente, en esta invención se incluyen enzimas quiméricas que contienen dicho módulo de unión a pared mejorado y se dan ejemplos de su a...

  2. Estudo da produção do suco clarificado de cajá (Spondias lutea L.)

    OpenAIRE

    SILVA,Antonio de Pádua Valença da; MAIA,Geraldo Arraes; OLIVEIRA,Gerardo Sérgio Francelino de; FIGUEIREDO,Raimundo Wilane de; BRASIL,Isabella Montenegro

    1999-01-01

    Cajás ( Spondias lutea L.), oriundos do município de Maranguape, Ceará, Brasil, foram processados em nível de escala-piloto para obtenção de suco clarificado através do emprego de enzimas pectinolíticas e agentes clarificantes. Aplicaram-se 120ppm de enzima pectinolítica (Pectinex Ultra SP-L) na polpa para obtenção do suco polposo e, em seguida, 500ppm de enzima pectinolítica (Pectinex-AR) no suco extraído, utilizando-se a "Prova do álcool" como indicador da presença de pectina. Para o proces...

  3. Avaliação da concentração de pectinase no processo de hidrólise-sacarificação do farelo de mandioca para obtenção de etanol

    Directory of Open Access Journals (Sweden)

    LEONEL M.

    2000-01-01

    Full Text Available Neste trabalho objetivou-se avaliar a concentração de pectinase (Pectinex Ultra SP-L no processo de hidrólise-sacarificação do farelo de mandioca para produção de etanol. Foram avaliadas quatro concentrações da enzima pectinase com enzima complemetar as amilases e o tratamento com apenas as amilases. Realizou-se a caracterização do hidrolisado e resíduo fibroso resultantes do processo, e os resultados obtidos demonstraram que a concentração mínima de pectinase para um bom rendimento do processo foi 8Kg enzima/t fibras, com. 89,4% do amido hidrolisado. Quanto ao resíduo fibroso, este apresenta potencialidade de aproveitamento com base para produtos dietéticos ricos em fibras.

  4. Clonación, expresión y caracterización de una nueva esterasa derivada de metagenomas de suelos agrícolas colombianos

    Directory of Open Access Journals (Sweden)

    Carolina Villamil

    2016-07-01

    Full Text Available El presente trabajo tuvo como objetivo la bioprospección de ADN metagenómico derivado de comunidades microbianas asociadas a un agroecosistema de importancia nacional. Este análisis permitió realizar la producción, expresión, purificación y caracterización de una enzima novedosa con actividad esterasa. Esta enzima, denominada LipM, había sido previamente identificada en clones metagenómicos derivados de suelos dedicados al cultivo de papa criolla (Solanum pureja, mediante secuencia de nueva generación y análisis bioinformáticos. La secuencia codificante de la enzima fue clonada en el vector pBADgiii y expresada en E. coli como sistema de expresión, lo que permitió optimizar el proceso de producción recombinante y su posterior purificación. Funcionalmente la enzima presentó una mayor afinidad por sustratos de p-nitrofenil con ácidos grasos de cadena corta (enzima exhibió buena estabilidad en presencia de varios iones metálicos, inhibidores y  0.1% (p/v de SDS. Su alto nivel de estabilidad en presencia de iones metálicos e inhibidores, así como su particular especificidad en cuanto a sustratos, la hacen una enzima óptima para utilización en diferentes aplicaciones biotecnológicas.

  5. Efeito da protease sobre o coeficiente de metabolizabilidade dos nutrientes em frangos de corte

    Directory of Open Access Journals (Sweden)

    C.F.Q. Matias

    2015-04-01

    Full Text Available Avaliaram-se os efeitos da protease sobre o coeficiente de metabolizabilidade dos nutrientes em dietas contendo farinha de penas (2,0% na fase inicial e 3,0% na fase de crescimento para frangos de corte machos, Cobb(r, de um a 32 dias de idade. Foram alojadas 336 aves em gaiolas metálicas equipadas com bandeja para coleta total de excretas. Foi utilizado delineamento inteiramente ao acaso, em arranjo fatorial 2x2 (com e sem adição da enzima protease 0,05% e duas valorizações da matriz nutricional da enzima, sendo sete repetições por tratamento, de 12 aves cada. Observou-se, na fase inicial, maior CMPB (P≤0,05 para as aves que, independentemente da adição de protease, consumiram ração com valorização da matriz nutricional da enzima. Não houve efeito dos tratamentos sobre o CMMS e o CMEE (P>0,05. Na fase de crescimento, houve interação entre os tratamentos para as variáveis CMPB e CMEE. Os frangos alimentados com dieta valorizada sem adição de enzima (controle negativo apresentaram melhores resultados (P≤0,05 para CMPB e CMEE. Nos tratamentos com enzima, o melhor CMEE (P≤0,05 foi obtido com o tratamento sem valorização da matriz nutricional (over the top. Conclui-se que níveis reduzidos e enzima sem valorização melhoram os coeficientes de metabolizabilidade dos nutrientes na fase adulta de frangos de corte.

  6. Tipos de pasteurização e agentes coagulantes na fabricação do queijo tipo prato

    OpenAIRE

    Ramos, Thaís de Melo

    2013-01-01

    O presente trabalho foi realizado com os objetivos de avaliar a influência do tipo de pasteurização pelos sistemas de aquecimento indireto high temperature short time, ou HTST, e injeção direta de vapor (IDV), e avaliar a influência de duas diferentes enzimas coagulantes na fabricação do queijo tipo prato. O delineamento experimental utilizado neste experimento foi um fatorial 2 x 2 x 5 inteiramente casualizado, sendo dois sistemas de pasteurização (HTST e IDV), duas enzimas coagulantes e cin...

  7. Detecção e caracterização de complexos multi-enzimáticos em secretoma de fungos filamentosos

    OpenAIRE

    Silva, Adelson Joel da

    2013-01-01

    As enzimas que degradam parede celular vegetal produzidas por micro-organismos possuem aplicações biotecnológicas importantes, incluindo a produção de bioetanol. Algumas batérias anaeróbicas são capazes de produzir complexos multi-enzimáticos chamados de celulosomos, enquanto os fungos filamentosos normalmente secretam enzimas hidrolíticas individuais que atuam sinergisticamente no processo de degradação de polissacarídeo. Neste trabalho, nós mostramos que os fungos filamentosos Trichoderm...

  8. Caracterização do secretoma de Aspergillus niger crescido em bagaço de cana e purificação de xilanases de interesse biotecnológico

    OpenAIRE

    Martins, Pedro Alves

    2012-01-01

    Os fungos filamentosos quando submetidos ao crescimento em meios contendo material lignocelulósico, são capazes de produzir diferentes tipos de enzimas extracelulares responsáveis por catalisar a hidrólise de celulose, hemicelulose e outros polissacarídeos encontrados nas paredes celulares vegetais. Algumas dessas enzimas podem ser aplicadas comercialmente em processos industriais, como nas indústrias alimentícia, têxtil, papeleira e também na produção de bioetanol. O fungo filamentoso mesofí...

  9. Expresión de β-1,3-Glucanasas de Beauveria bassiana en cultivo con extracto de los fitopatógenos Peronospora variabilis y Fusarium oxysporum

    OpenAIRE

    Montoya Espinoza, W. Jhoel; Nolasco Cárdenas, Oscar P; Acuña Payano, Rosalyn K; Gutiérrez, Ana I. F

    2016-01-01

    El hongo Beauveria bassiana Vuill. es muy conocido por su capacidad entomopatógena, pero también existe referencias de ser un hongo antagonista, una de las posibles formas de su antagonismo es la antibiosis debido a la presencia de enzimas hidrolíticas en su genoma. Las principales enzimas expresadas contra fitopatógenos son las β-1,3-glucanasas, ya que la pared celular de los fitopatógenos como hongos y oomycetes está constituida en su mayoría por polímeros de β-1,3-glucanos. Se evaluó por q...

  10. Avaliação da atividade da superóxido dismutase e catalase de Candida albicans e Candida dubliniensis expostas a antineoplásicos, íons metálicos e antifúngicos

    OpenAIRE

    Carlos Eduardo Blanco Linares

    2009-01-01

    A atividade de catalase em Candida albicans tem sido sugerida como um mecanismo de resistência ao antifúngico anfotericina B. Neste contexto, poucos são os estudos de enzimas como catalase e superóxido dismutase em leveduras do gênero Candida expostas a diferentes situações. Assim, este estudo teve por objetivo investigar o efeito da exposição de Candida a antineoplásicos, íons metálicos e antifúngicos como fluconazol e anfotericina B sobre a atividade dessas enzimas. Os resultados apontaram ...

  11. Deterioro del pescado: Guía didáctica

    OpenAIRE

    Oliveira, C.; Dragonetti Saucero, J.P.; Friss, C.

    2001-01-01

    Después de la captura y muerte del pescado, éste sufre inmediatamente un deterioro, la velocidad de degradación es más elevada que la de otros tipos de carnes. Este proceso de degradación es llevado a cabo en una primera etapa, por enzimas propias del músculo del pescado y posteriormente por enzimas producidas por los microrganismos que ingresan al músculo. La velocidad de deterioro varía según las especies dependiendo de diversos factores, tales como tamaño, estado fisiológico, alimentación ...

  12. Sensores de zinc para aplicaciones en neurociencias

    OpenAIRE

    Estela Falla, Aldo David; Estela Falla, Aldo David; Estela Falla, Aldo David

    2011-01-01

    En los últimos años, los estudios realizados con respecto a la química involucrada en los procesos neurológicos han logrado dar una idea de la importancia del zinc en las funciones nerviosas, así como también en el estudio de enfermedades neurodegenerativas tales como la Enfermedad de Alzheimer. A nivel biológico, el zinc tiene representantes en los seis grupos de enzimas que existen, lo cual demuestra su gran importancia en los sistemas biológicos. En estas enzimas, el zinc como ion metál...

  13. Estudo de produção enzimatica da dextrana clinica

    OpenAIRE

    Juan Heraldo Viloche Bazan

    1993-01-01

    Resumo: Este trabalho consiste na obtenção "in vitro" de dextrana clínica a partir da sacarose utilizando a enzima dextrana-sacarase obtida pela fermentação do Leuconostoc mesenteroides linhagem NRRL B512-F. A dextrana clínica, de peso molecular médio 40.000 daltons, tem sua aplicação consagrada como expansor volumétrico de sangue humano. A enzima foi produzida por fermentação e purificada usando ultrafiltração, separada com o uso de polietilenoglicol de peso molecular 1500 daltons e estocada...

  14. Estudo das condições de hidrolise acida para obtenção de dextrana clinica

    OpenAIRE

    Vanessa Mendes Santos

    1996-01-01

    Resumo: A dextrana é um biopolímero formado por resíduos de glicose unidos por ligação et-1,6 maioritariamente. É sintetizada peia enzima dextrana-sacarase, enzima esta produzida extracelularmente por algumas bactérias, principalmente do genêro Leuconosíoa A apiicacão deste polímero está diretamente relacionada com o seu peso molecular- As dextranas de peso molecular na faixa de 20,000 a 100,000 daltons (dextrana clínica) possui notáveis aplicações no ramo da medicina como expansor do plasma ...

  15. Estudio de las propiedades de las colinesterasas en epitelios de las vías aéreas superiores humanas y sus alteraciones en el cáncer

    OpenAIRE

    Castillo González, Ana Cristina

    2016-01-01

    Objetivos Los objetivos principales de la presente Tesis Doctoral son: 1. Determinar los niveles de actividad Acetilcolinesterasa (AChE) y Butirilcolinesterasa (BChE) en epitelios sanos y tumorales de laringe. 2. Analizar los componentes de formas moleculares de las enzimas en tejidos sanos y patológicos. 3. Identificar y cuantificar los distintos transcritos de AChE y BChE, de la enzima colina-acetil transferasa (ChAT) y de distintas subunidades de los receptores nicotínicos...

  16. Descoloração de efluentes têxteis sintéticos por catálise enzimática

    OpenAIRE

    Silva, Maria Cristina; Corrêa, Angelita D.; Amorim, M. T. Pessoa de; Oliveira, Sara L. C.; Duarte, António A. L. Sampaio; Torres, Juliana A.

    2010-01-01

    Peroxidases podem ser utilizadas em processos de descoloração no tratamento de efluentes têxteis. Há um interesse crescente por novas fontes desta enzima, e por processos de obtenção viáveis economicamente.1Neste trabalho o potencial de descoloração de efluentes têxteis sintéticos por peroxidase extraída de nabo (Brassica campestre ssp. rapifera) é avaliado. Para a obtenção da enzima de baixa pureza utiliza-se um processo de baixo custo, Os efluentes utilizados nos ensaios são efluentes sinté...

  17. Purificación y caracterización de poligalacturonasas de Aspergillus kawachii

    OpenAIRE

    Contreras Esquivel, Juan Carlos

    2003-01-01

    El desarrollo de nuevas aplicaciones de las pectinasas depende de la búsqueda de enzimas que catalizen reacciones novedosas o que presenten propiedades diferentes a las ya estudiadas. Considerando la capacidad de A. kawachii de producir enzimas activas en condiciones de alta acidez y al escaso conocimiento de su sistema pectolítico, se inició un proyecto de investigación dirigido a estudiar las pectinasas de este microorganismo. El presente trabajo de Tesis se enmarcó en los objetivos de dich...

  18. Clonación, expresión y caracterización de una nueva esterasa derivada de metagenomas de suelos agrícolas colombianos

    OpenAIRE

    Carolina Villamil; Patricia Del Portillo; Alvaro Monguí

    2016-01-01

    El presente trabajo tuvo como objetivo la bioprospección de ADN metagenómico derivado de comunidades microbianas asociadas a un agroecosistema de importancia nacional. Este análisis permitió realizar la producción, expresión, purificación y caracterización de una enzima novedosa con actividad esterasa. Esta enzima, denominada LipM, había sido previamente identificada en clones metagenómicos derivados de suelos dedicados al cultivo de papa criolla (Solanum pureja), mediante secuencia de nueva ...

  19. Inmovilización de transaminasas y amonio liasas y su aplicación en síntesis de compuestos aminados

    OpenAIRE

    Cárdenas Fernández, Anthony Max

    2012-01-01

    El objetivo del presente trabajo de tesis es establecer métodos biocatalíticos para la síntesis de los aminoácidos L-fenilalanina, L-aspartato, β−aminobutirato y de las aminas aromáticas 1-feniletilamina y 3-amino-1-fenilbutano, usando biocatalizadores con actividad transaminasa y amonio liasa inmovilizados por técnicas de formación de enlaces covalentes (en el caso de enzimas) y por atrapamiento (tanto para enzimas como para células). Se establecieron dos métodos enzimáticos para la síntesis...

  20. Aplicación de la Transglutaminasa como ingrediente funcional para mejorar las propiedades tecnológicas en yogur y queso fresco

    OpenAIRE

    Miró Fuertes, Elisabet

    2017-01-01

    La transglutaminasa es una enzima que se encuentra de forma natural en la mayoría de tejidos animales y está relacionada con varios procesos biológicos. Esta enzima actúa únicamente en proteínas catalizando la reacción de formación de enlaces covalentes entre residuos de glutamina y lisina entre proteínas de distinto tipo y origen. El añadir transglutaminasa en nuevas formulaciones confiere al producto nuevas propiedades en la estructura y acabado de los mismos aumentando su valor añadido. En...

  1. Sacarificación enzimática para la producción de jarabe glucosado

    OpenAIRE

    Flórez Franco, Olga Elena; Uribe Restrepo, Nora Dabeiba

    2001-01-01

    En este trabajo se evaluó la producción de jarabe glucosado a partir de la sacarificación de maltodextrina con enzima glucoamilasa libre, para tres concentraciones de maltodextrina (20, 40 y 60 g/l) y tres concentraciones de enzima glucoamilasa (0,75000; 0,43125 y 0,11250 AGU/ml), con un diseño experimental tres factorial, a temperatura de 60 ºC y pH 4,3. El propósito era encontrar las concentraciones óptimas de producción de glucosa, teniendo como variables de respuesta el equivalente de dex...

  2. Hemo-oxigenasa 1: un promisorio blanco terapéutico

    OpenAIRE

    Sánchez, Carlos; Rodeiro, Idania; Garrido-Garrido, Gabino; Delgado, René

    2005-01-01

    La enzima hemo-oxigenasa es la principal enzima implicada en el catabolismo del grupo hemo y da lugar a tres productos fundamentales: biliverdina, el hierro libre y el monóxido de carbono. Fue descubierta a principios de la década del 60, pero no fue hasta mediado de los años ´80 donde empezó a estudiarse con detenimiento y se determinó que existía una isoforma inducible, denominada hemo oxigenasa-1. Esta proteína juega un papel muy importante en la modulación de procesos inflamatorios y eso ...

  3. A View of DANIDAs Policy Note on Food Security through A Policy Coherent Lens

    DEFF Research Database (Denmark)

    Robertson, Aileen

    2014-01-01

    -usikkerhed hæmmer udvikling’ understreges det, at hvis ‘underernæring’ og ‘sult’ forveksles, findes disse synergier ikke og sparsomme resourcer spildes. I Danida`s ’Policy Note on Food Security’ nævnes det, at ‘852 million are living in hunger’, altså sult. Det er imidlertid snarere kronisk underernæring end sult...... Greener World for All (NEC)’. Faktisk peger man på, at landbrugets og fødevaresektorens primære rolle er at brødføde befolkningen ved at øge tilgængeligheden og forbruget af sikre, miljørigtige madvarer, der er i overensstemmelse med ernæringsmæssige anbefalinger og til overkommelige priser. Derfor...

  4. Multiple analytical approaches reveal distinct gene-environment interactions in smokers and non smokers in lung cancer.

    Directory of Open Access Journals (Sweden)

    Rakhshan Ihsan

    Full Text Available Complex disease such as cancer results from interactions of multiple genetic and environmental factors. Studying these factors singularly cannot explain the underlying pathogenetic mechanism of the disease. Multi-analytical approach, including logistic regression (LR, classification and regression tree (CART and multifactor dimensionality reduction (MDR, was applied in 188 lung cancer cases and 290 controls to explore high order interactions among xenobiotic metabolizing genes and environmental risk factors. Smoking was identified as the predominant risk factor by all three analytical approaches. Individually, CYP1A1*2A polymorphism was significantly associated with increased lung cancer risk (OR = 1.69;95%CI = 1.11-2.59,p = 0.01, whereas EPHX1 Tyr113His and SULT1A1 Arg213His conferred reduced risk (OR = 0.40;95%CI = 0.25-0.65,p<0.001 and OR = 0.51;95%CI = 0.33-0.78,p = 0.002 respectively. In smokers, EPHX1 Tyr113His and SULT1A1 Arg213His polymorphisms reduced the risk of lung cancer, whereas CYP1A1*2A, CYP1A1*2C and GSTP1 Ile105Val imparted increased risk in non-smokers only. While exploring non-linear interactions through CART analysis, smokers carrying the combination of EPHX1 113TC (Tyr/His, SULT1A1 213GG (Arg/Arg or AA (His/His and GSTM1 null genotypes showed the highest risk for lung cancer (OR = 3.73;95%CI = 1.33-10.55,p = 0.006, whereas combined effect of CYP1A1*2A 6235CC or TC, SULT1A1 213GG (Arg/Arg and betel quid chewing showed maximum risk in non-smokers (OR = 2.93;95%CI = 1.15-7.51,p = 0.01. MDR analysis identified two distinct predictor models for the risk of lung cancer in smokers (tobacco chewing, EPHX1 Tyr113His, and SULT1A1 Arg213His and non-smokers (CYP1A1*2A, GSTP1 Ile105Val and SULT1A1 Arg213His with testing balance accuracy (TBA of 0.6436 and 0.6677 respectively. Interaction entropy interpretations of MDR results showed non-additive interactions of tobacco chewing with

  5. INFLUENCE OF MOTOR CAPaBILITIES AND COGNITiVE CHARACTERISTICS ON SPEED OF LEADING THE BALL AND ACCURACY IN BASKETBALL

    Directory of Open Access Journals (Sweden)

    Rašid Hadžić

    2007-05-01

    Full Text Available In goal of for ti fi ca tion the sca le of in fl u en ce of mo tor ca pa bi li ti es and cog ni ti ve cha rac te ri stics on re sult suc cess in ball le a ding speed and si tu a te ac cu racy in ba sket ball re sults de ri ved from sam ple of 105 boys bet we en 14 and 16 years ha ve been analyzed. Re gres si ve analyze of cri te ria va ri a ble SMKVLS and va ri a ble SMKBVL gi ves suf fi ci ent in for ma tion abo ut in fl u en ce of ap plied mo tor and cog ni ti ve on suc cess of per for ming of tre a ted cri te ria va ri a ble

  6. Case report

    African Journals Online (AJOL)

    raoul

    21 déc. 2011 ... Abstract. La thrombasthenie de Glanzmann est une anomalie plaquettaire qualitative, à transmission autosomale récessive, due à un déficit en glycoprotéine. IIb/IIIa (GPIIb/IIIa), avec un défaut d'agrégation plaquettaire. Il en résulte une perturbation de l'hémostase primaire, à l'origine d'hémorragie plus.

  7. Linear- and Repetitive-Feature Detection Within Remotely Sensed Imagery

    Science.gov (United States)

    2017-04-01

    preprocessing image data, which has proven difficult and intensive for certain images. In many cases, the amount of user interaction needed to produce...a way that humans can easily understand. This data is represented as if there was a light source located to the northwest with an altitude angle of...them. Although there are some shortcomings to this methodology, the final re- sult is useful and would help a user or analyst distinguish the layout

  8. Linear- and Repetitive Feature Detection Within Remotely Sensed Imagery

    Science.gov (United States)

    2017-04-01

    preprocessing image data, which has proven difficult and intensive for certain images. In many cases, the amount of user interaction needed to produce...a way that humans can easily understand. This data is represented as if there was a light source located to the northwest with an altitude angle of...them. Although there are some shortcomings to this methodology, the final re- sult is useful and would help a user or analyst distinguish the layout

  9. Polymorphism’s assessment of children’s candidate genes associated with low-level long-term exposure to strontium in drinking water

    OpenAIRE

    N.V. Zaitseva; O.V. Dolgilh; A.V. Krivtsov; K.G. Starkova; V.A. Luchnikova; O.A. Bubnov; E.A. Otavina; N.V. Bezruchenko; N.A. Vdovina

    2015-01-01

    A sequencing of the candidate genes of the pupils, exposed to strontium by the method of targeted resequencing has been performed. It is shown, that under conditions of increased revenues of strontium in drinking water the number of polymorphonuclear altered portions of candidate genes increases. As a result of the targeted resequencing in conditions of strontium exposure, the maximum polymorph modifications of the following genes are defined: sulfotransferase 1A1 (SULT1A1) and methylenetetra...

  10. Identification of nevadensin as an important herb-based constituent inhibiting estragole bioactivation and physiology-based biokinetic modeling of its possible in vivo effect

    International Nuclear Information System (INIS)

    Alhusainy, W.; Paini, A.; Punt, A.; Louisse, J.; Spenkelink, A.; Vervoort, J.; Delatour, T.; Scholz, G.; Schilter, B.; Adams, T.; Bladeren, P.J. van; Rietjens, I.M.C.M.

    2010-01-01

    Estragole is a natural constituent of several herbs and spices including sweet basil. In rodent bioassays, estragole induces hepatomas, an effect ascribed to estragole bioactivation to 1'-sulfooxyestragole resulting in DNA adduct formation. The present paper identifies nevadensin as a basil constituent able to inhibit DNA adduct formation in rat hepatocytes exposed to the proximate carcinogen 1'-hydroxyestragole and nevadensin. This inhibition occurs at the level of sulfotransferase (SULT)-mediated bioactivation of 1'-hydroxyestragole. The Ki for SULT inhibition by nevadensin was 4 nM in male rat and human liver fractions. Furthermore, nevadensin up to 20 μM did not inhibit 1'-hydroxyestragole detoxification by glucuronidation and oxidation. The inhibition of SULT by nevadensin was incorporated into the recently developed physiologically based biokinetic (PBBK) rat and human models for estragole bioactivation and detoxification. The results predict that co-administration of estragole at a level inducing hepatic tumors in vivo (50 mg/kg bw) with nevadensin at a molar ratio of 0.06, representing the ratio of their occurrence in basil, results in almost 100% inhibition of the ultimate carcinogen 1'-sulfooxyestragole when assuming 100% uptake of nevadensin. Assuming 1% uptake, inhibition would still amount to more than 83%. Altogether these data point at a nevadensin-mediated inhibition of the formation of the ultimate carcinogenic metabolite of estragole, without reducing the capacity to detoxify 1'-hydroxyestragole via glucuronidation or oxidation. These data also point at a potential reduction of the cancer risk when estragole exposure occurs within a food matrix containing SULT inhibitors compared to what is observed upon exposure to pure estragole.

  11. MUSIC-CONTENT-ADAPTIVE ROBUST PRINCIPAL COMPONENT ANALYSIS FOR A SEMANTICALLY CONSISTENT SEPARATION OF FOREGROUND AND BACKGROUND IN MUSIC AUDIO SIGNALS

    OpenAIRE

    Papadopoulos , Hélène; Ellis , Daniel P.W.

    2014-01-01

    International audience; Robust Principal Component Analysis (RPCA) is a technique to decompose signals into sparse and low rank components, and has recently drawn the attention of the MIR field for the problem of separating leading vocals from accompaniment, with appealing re-sults obtained on small excerpts of music. However, the perfor-mance of the method drops when processing entire music tracks. We present an adaptive formulation of RPCA that incorporates music content information to guid...

  12. The Shock and Vibration Bulletin. Part 2. Isolation and Damping, Impact, Blast

    Science.gov (United States)

    1978-09-01

    statistically distributed. "What is a reasonable value of the •- •- circumferential strain at failure, When a relationship is known be- efail ...of theinput design parameters. (These re- that is, the probability that the sults are presented in Table I). failure strain ( efail ) is exceeded...strain efail was set at 0.05 [cf..qua- 6, one has a frequency distribution of tion (5)].the number of occurrences vs. liner "strain, e. For the

  13. Algunos aspectos de la hidroquímica del sistema acuífero Botucatú (Cuenca del Paraná, Estado de Sáo Paulo, Brasil)

    OpenAIRE

    Campos, H. C.; Cerón García, Juan Carlos

    1997-01-01

    The principal hydrochemical features of the Botucatú aquifer system in Sao Paulo State - SE Brasil - was studied from 67 groundwater chemical analysis. Westward, in the Botucatú aquifer system the progressive confining condition, with depth of the top of aquifer layer, increases the groundwater temperature slowly. Moreover, the residence time increases the water salt content towards the natural flow direction (E-W). As résults ,th'e recent calcium and magnesium bicarbonate groundwater cha...

  14. Proceedings of the Conference on the Stability and Dynamic Response of Rotors with Squeeze Film Bearings, 8-10 May 79.

    Science.gov (United States)

    1979-01-01

    in flexible engine rotors and structures. 2. Small physical size, especially in frontal area and wheel diameter. 3. Increasingly higher shaft speeds...requirements for high power and small wheel diameter re- sults in extremely small blade tip clearances. This limits the acceptable rotor disk excursions...installation, alignment of the damper center with the bearing centers should be accurately maintained, lest runout error would cause excitations at rota

  15. Strategy and Grand Strategy: What Students and Practitioners Need to Know

    Science.gov (United States)

    2015-12-01

    Press publications may be downloaded free of charge from the SSI website. Hard copies of certain reports may also be obtained free of charge while...and means. Strategy rests on assump- tions; if assumptions go unexamined, then one risks building a strategic edifice on a foundation of sand .4 Often...Similar outcomes re- sult if civilians believe that military leaders are trying to game, stack, or stall a consequential decision. Wary of all this

  16. 2011 Agile (Scrum) Workshop Held in Baltimore, Maryland on November 14-15, 2011

    Science.gov (United States)

    2011-11-15

    ment melded with CMMI Level 3 discipline. Her programs put the end-user in control of priorities and delivered capabilities re- sulting in a...OPS PEX Team: Internal •Devs/ SMEs /Testers •Architecture Committee •Etc. none Future implementation, not Current release Big R/Little r I n...Refine Pre-release Planning Release Planning Release Execution Post- release POT: ( SMEs and Developers) •Based on Approved Roadmap •Decomposes

  17. New Methods for the Computational Fabrication of Appearance

    Science.gov (United States)

    2015-06-01

    constraint. The only variables are the values of u and the coecients ↵ i . In our current implementation, we chose a radial thin - plate spline basis h i (r...61] use thin - plate implicit functions to create a smooth morphing between two surfaces. Techniques more similar to our work include [4], who used...the thin - plate energy re- sulting in higher curvature in concentrated regions. On the left, minimizing the third derivative energy which results in

  18. Short-term calorie restriction feminizes the mRNA profiles of drug metabolizing enzymes and transporters in livers of mice.

    Science.gov (United States)

    Fu, Zidong Donna; Klaassen, Curtis D

    2014-01-01

    Calorie restriction (CR) is one of the most effective anti-aging interventions in mammals. A modern theory suggests that aging results from a decline in detoxification capabilities and thus accumulation of damaged macromolecules. The present study aimed to determine how short-term CR alters mRNA profiles of genes that encode metabolism and detoxification machinery in the liver. Male C57BL/6 mice were fed CR (0, 15, 30, or 40%) diets for one month, followed by mRNA quantification of 98 xenobiotic processing genes (XPGs) in the liver, including 7 uptake transporters, 39 phase-I enzymes, 37 phase-II enzymes, 10 efflux transporters, and 5 transcription factors. In general, 15% CR did not alter mRNAs of most XPGs, whereas 30 and 40% CR altered over half of the XPGs (32 increased and 29 decreased). CR up-regulated some phase-I enzymes (fold increase), such as Cyp4a14 (12), Por (2.3), Nqo1 (1.4), Fmo2 (5.4), and Fmo3 (346), and numerous number of phase-II enzymes, such as Sult1a1 (1.2), Sult1d1 (2.0), Sult1e1 (33), Sult3a1 (2.2), Gsta4 (1.3), Gstm2 (1.3), Gstm3 (1.7), and Mgst3 (2.2). CR feminized the mRNA profiles of 32 XPGs in livers of male mice. For instance, CR decreased the male-predominantly expressed Oatp1a1 (97%) and increased the female-predominantly expressed Oatp1a4 (11). In conclusion, short-term CR alters the mRNA levels of over half of the 98 XPGs quantified in livers of male mice, and over half of these alterations appear to be due to feminization of the liver. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Semiannual Report to the Congress: April 1, 2013 to September 30, 2013

    Science.gov (United States)

    2013-09-30

    providers’ selection and utilization of Aranesp within nursing homes, skilled nursing facilities and long-term care settings. reSult: On April 4... nurse case managers, are appropriate to meet the mission for effective management and support of soldiers during their healing and transition...needs to perform additional audit procedures to support the audit conclusions and overall audit opinion. DoD IG will reschedule its review once the

  20. Fort Hood Army Internal Review Team: Final Report

    Science.gov (United States)

    2010-08-04

    lead to or re- sult in violent acts. 2. Finding 2.3 - DoD standards for denying requests for recognition as an ecclesiastical endorser of chaplains may...review and pos- sible revision to ensure the supporting architecture and capabilities exist to support the mission. No cost estimate is necessary to...enterprise architecture . The goal is to field interoperable installation physi- cal access control systems that can access the Defense Manpower Data

  1. Polymorphic Human Sulfotransferase 2A1 Mediates the Formation of 25-Hydroxyvitamin D3-3-O-Sulfate, a Major Circulating Vitamin D Metabolite in Humans.

    Science.gov (United States)

    Wong, Timothy; Wang, Zhican; Chapron, Brian D; Suzuki, Mizuki; Claw, Katrina G; Gao, Chunying; Foti, Robert S; Prasad, Bhagwat; Chapron, Alenka; Calamia, Justina; Chaudhry, Amarjit; Schuetz, Erin G; Horst, Ronald L; Mao, Qingcheng; de Boer, Ian H; Thornton, Timothy A; Thummel, Kenneth E

    2018-04-01

    Metabolism of 25-hydroxyvitamin D 3 (25OHD 3 ) plays a central role in regulating the biologic effects of vitamin D in the body. Although cytochrome P450-dependent hydroxylation of 25OHD 3 has been extensively investigated, limited information is available on the conjugation of 25OHD 3 In this study, we report that 25OHD 3 is selectively conjugated to 25OHD 3 -3- O -sulfate by human sulfotransferase 2A1 (SULT2A1) and that the liver is a primary site of metabolite formation. At a low (50 nM) concentration of 25OHD 3 , 25OHD 3 -3- O -sulfate was the most abundant metabolite, with an intrinsic clearance approximately 8-fold higher than the next most efficient metabolic route. In addition, 25OHD 3 sulfonation was not inducible by the potent human pregnane X receptor agonist, rifampicin. The 25OHD 3 sulfonation rates in a bank of 258 different human liver cytosols were highly variable but correlated with the rates of dehydroepiandrosterone sulfonation. Further analysis revealed a significant association between a common single nucleotide variant within intron 1 of SULT2A1 (rs296361; minor allele frequency = 15% in whites) and liver cytosolic SULT2A1 content as well as 25OHD 3 -3- O -sulfate formation rate, suggesting that variation in the SULT2A1 gene contributes importantly to interindividual differences in vitamin D homeostasis. Finally, 25OHD 3 -3- O -sulfate exhibited high affinity for the vitamin D binding protein and was detectable in human plasma and bile but not in urine samples. Thus, circulating concentrations of 25OHD 3 -3- O -sulfate appear to be protected from rapid renal elimination, raising the possibility that the sulfate metabolite may serve as a reservoir of 25OHD 3 in vivo, and contribute indirectly to the biologic effects of vitamin D. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  2. DYNAMIC OF BIOMECHANIC TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Duško Bjelica

    2007-05-01

    Full Text Available The mo ving con sists of a set of mo ve ments ma de on right ti me with a ca re fully cho sen in ten sity. Every com po sed mo ving is har mo ni o us but if we ru i ned that har mony in only one se ge ment, if only one mo ve ment was ma de too early or too la te with a gre a ter for ce, it wo uld de stroy the who le pro ce du re and the re sult wo uldn’t be op ti mal.The analysis of every com po sed sport mo ve ment is usu ally do ne in two pha ses: in the fi rst one it sho uld be esta blis hed the le vel of the tec hni cal know led ge, and in the se cond that know led ge sho uld be com pa red to the tec hi que of the sport man in that di sci pli ne. The only in di ca tors of the tec hni que of com plex mo ve ment are the fi rst and the second re sults of the ex ce e ded way and the se i zed an gle from the ac tual and re pre sen ta ti ve po int that are re pre sen ted di gi tally and by ana lo gue. When we com pa re tho se re sults with the re sults of a top spor tsman we will be co me awa re of the de vi a tion from the op ti mal compo si tion of the mo ve ments in to a mo ving and we will esta blish a re la ti on ship bet we en the fa i lu res and the ir con se qu en ces.

  3. 2741-IJBCS-Proof-Njoyim Estella Buleng T

    African Journals Online (AJOL)

    hp

    Néanmoins, le chrome et fer étaient fortement concentrés dans presque tous les échantillons au mois de janvier (0,14 à ...... d'eau, augmentant ainsi les infections observées en ces mois. Ce cycle résulte en l'occurrence des infections d'origine hydrique tout au long de l'année. Conclusion. A l'issue des analyses physiques,.

  4. Serological study of Helicobacter pylori infection in patients with Polycystic Ovary Syndrome

    Directory of Open Access Journals (Sweden)

    Farnaz Sohrabvand

    2014-01-01

    Conclusion: This study showed no significant difference in serologic examination re-sults in PCOS versus non PCOS patients. The finding of high prevalence of H.Pylori IgG and IgA positive levels in both PCOS and non PCOS patients can be probably re-lated to the high prevalence of H.Pylori infection or exposure in Iranian population and therefore suggest an issue for further investigation.

  5. Rendre les villes plus sûres grâce à l'emploi et à la rémunération

    International Development Research Centre (IDRC) Digital Library (Canada)

    crimes contre les biens (et non des crimes « payants » pour les criminels). Certains analystes croient que le taux de criminalité élevé de l'Afrique du. Sud résulte de la fracture psychologique et sociale qui survient lorsqu'un grand nombre de personnes est laissé pour compte au sein d'une société d'abondance. « L'inégalité ...

  6. Enfants travailleurs domestiques a cotonou : Entre contraintes ...

    African Journals Online (AJOL)

    Le décalage de perception sur le travail des enfants résulte d'abord de la définition du concept d'enfant perçu différemment selon qu'il s'agit des normes juridiques ou des codes sociaux ou communautaires. ... Par conséquent, la domesticité enfantine ressemble davantage à un projet élaboré par un ensemble d'acteurs.

  7. Modelling, Information, Processing, and Control

    Science.gov (United States)

    1989-01-15

    have studied the use of transfer function methods to analyze closed - loop systems arising out of cer- tain linear feedback laws , use of transfer...classical Muntz- Szasz theory of real exponentials. As a re- sult it is seen that D has domain including that of A I / 2 in all cases. Further work is...approximation questions, we will discuss the use of transfer function methods to analyze closed - loop systems arising out of cer- tain linear feedback laws

  8. Use of GERAM as Basis for a Virtual Enterprise Framework Model

    DEFF Research Database (Denmark)

    Vesterager, Johan; Bernus, Peter; Larsen, Lars B

    2001-01-01

    In the IMS-project Globeman21, the enterprise reference architecture GERAM was used as basis for creation of a virtual enterprise framework model. The model was used to map different industrial pilot projects, to classify virtual en-terprise concepts, and as underlying structure for a virtual...... enterprise manage-ment methodology. The paper gives a survey of the use of GERAM and the re-sults obtained....

  9. Model-Driven Engineering: Automatic Code Generation and Beyond

    Science.gov (United States)

    2015-03-01

    herein to any specific commercial product, process, or service by trade name, trade mark, manufacturer , or otherwise, does not necessarily constitute or...export of an Extensible Markup Language (XML) representation of the model. The XML Metadata Interchange (XMI) is an OMG standard for representing...overall company financial results for the past 3 years. What financial re- sults are you projecting for the next year? 1.2.5.2 Percentage of Gross

  10. ÉTUDE DE CAS — mondiale : Repenser les stratégies de recherche ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    24 déc. 2010 ... Le composite qui en a résulté -- appelé MKC, pour Maria Kaherero Composite -- a servi de base au programme national de sélection végétale du pays. Sperling fait une mise en garde : la non-participation des femmes à la sélection végétale pourrait avoir des conséquences néfastes, pas seulement ...

  11. Comité Scientifique de la Revue des Sciences et de la Technologie ...

    African Journals Online (AJOL)

    MICROSIM

    du Turonien enregistrent les variations lithologiques et microfaunistique relatives à l'événement anoxique océanique 2 (EAO-2). Les calcaires ... depuis des bassins océaniques profonds à des mers peu profondes [2, 3]. Cette crise résulte ..... tectonique, de la subsidence: une mise au point- Bulletin de la société géologique ...

  12. Combat-Related Heterotopic Ossification: Development of Animal Models for Identifying Mechanisms and Testing Therapeutics

    Science.gov (United States)

    2016-03-01

    ulcerate, or envelop neurovascular structures causing pro- gressive deficits .10-14 As a result, up to 41% of patients with HO will ultimately require...in a logarithmic fashion under optimal culture and nutrient conditions re- sulting in a controlled cell growth rate. Next, 2 mL of the concentrated...Cooper RR, Saltzman CL. Bone and brain: a review of neural, hormonal , and muscu- loskeletal connections. Iowa Orthop J. 2004;24:123. 19. Mo IF, Yip KH

  13. Structural Metadata Research in the Ears Program

    Science.gov (United States)

    2005-01-01

    detecting structural information in the word stream (the so-called “structural MDE” portion of the EARS program); other MDE efforts on speaker ... diarization are overviewed in [13]. The rest of this paper is organized as follows. We describe the structural MDE tasks, performance measurement, and corpora...tems have only recently been introduced, with NIST reporting re- sults with the Wilcoxon signed rank test for speaker -level average score differences

  14. Aquaculture en système clos : estimation des coûts de production pour l'élevage du bar et du turbot

    OpenAIRE

    Lavenant, M; Paquotte, Philippe

    1995-01-01

    Two major constraints to aquaculture have raised in most countries : the little availability of convenient sites because of the competition for the use of the coastline and the progressive implementation of regulations to reduce the impact of the farms on the environment. The technique of recirculation, widely used for hatcheries, has been developed to answer these constraints and to get free of the natural variations in order to regulate the résults. The ongrowing experimental facilities hav...

  15. Detonation Processes USSR

    Science.gov (United States)

    1960-06-06

    second and quite definite for a given combustible mixture -- was an important. cientific re- sult of these researches discovered in 18881 by four...Consequently, the pulsating structure of the front of the "rnorr.ia]" detonation should be quite comrmon. (1) See K. i. Shchelkin, " Journal of...A1 "-൚ " 4 FOR REASONS OF SPEED AND ECONOMY THIS REPORT HAS BEEN REPRODUCED ELECTRONICALLY DIPWCTLY PROM OUR CONTRACTOR’S TYPESCRIPT THIS PUBLICATION

  16. Chemical and structural order in silicon oxynitrides by methods of surface physics

    Science.gov (United States)

    Finster, J.; Heeg, J.; Klinkenberg, E.-D.

    A large number of thin amorphous layers of SiO xN y and several (crystalline) reference compounds (SiO 2, Si 3N 4, Si 2N 2O) are studied. Although XANES and SEXAFS are well sulted to derive structural and chemical order, for these compounds many problems remain to be solved. We show how core level spectra (XPS, AES) can be used to gain such information (e.g. random bonding structure, N coordination, oxidation behaviour).

  17. AcEST: DK944467 [AcEST

    Lifescience Database Archive (English)

    Full Text Available sults ■■ - Swiss-Prot (release 56.9) Link to BlastX Result : Swiss-Prot sp_hit_id O24339 Definition sp|O24339|CATA_SOLAP........................done Score E Sequences producing significant alignments: (bits) Value sp|O24339|CATA_SOLAP...TA_IPOBA Catalase OS=Ipomoea batatas PE=2 SV=1 248 2e-65 >sp|O24339|CATA_SOLAP Ca

  18. Wind pressure testing of tornado safe room components made from wood

    Science.gov (United States)

    Robert Falk; Deepak Shrestha

    2016-01-01

    To evaluate the ability of a wood tornado safe room to resist wind pressures produced by a tornado, two safe room com-ponents were tested for wind pressure strength. A tornado safe room ceiling panel and door were static-pressure-tested according to ASTM E 330 using a vacuum test system. Re-sults indicate that the panels had load capacities from 2.4 to 3.5 times that...

  19. Social Impacts Module (SIM) Transition

    Science.gov (United States)

    2012-09-28

    or OABs. An agent can communicate about events, seek resources, or do nothing. This basic procedure repeats itself continuously. See Appendix C for a...still contains the ability to represent key leaders and social networks and there are no changes to the procedures described for SIM 2.0 regarding...of the study question, MAJ Ja- son Whipple of WSMR trav- eled to Monterey to sup- port designing the Nexus scenario. The meeting re- sulted in

  20. De nouvelles variétés de pomme de terre pour lutter contre la ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    C'est la principale culture à laquelle s'adonnent les membres de 67 collectivités autochtones dans le département de Nariño, la région qui affiche le deuxième plus fort taux de malnutrition en Colombie. Pourtant, cette culture est fort susceptible au mildiou et donne, par conséquent, de faibles rendements. Il en résulte une ...

  1. Mathematics in Ancient India

    Indian Academy of Sciences (India)

    In this series of articles, we intend to have a glimpse of some of the landmarks ... then the complete solution due to J ayadeva and .... on the numerical and not so much on the proper geo- .... sult of which children all over the world learn it even at a tender age .... own right as well as an indispensable tool in other fields. In fact ...

  2. Le CRDI au Bhoutan

    International Development Research Centre (IDRC) Digital Library (Canada)

    Il en résulte des solutions locales, novatrices et durables, qui offrent des choix aux personnes qui en ont le plus besoin et font changer les choses. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. Pour en savoir plus, consulter la page. Web du Bureau régional de ...

  3. Le CRDI au Kenya

    International Development Research Centre (IDRC) Digital Library (Canada)

    afin d'y favoriser la croissance et le développement. Il en résulte des solutions novatrices et durables qui ont pour but d'améliorer les conditions de vie et les moyens de subsistance. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. Pour en savoir plus, consulter.

  4. Le CRDI en Jordanie

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... dans les pays en développement afin d'y favoriser la croissance et le développement. Il en résulte des solutions novatrices et durables qui ont pour but d'améliorer les conditions de vie et les moyens de subsistance. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9.

  5. Le CRDI en Égypte

    International Development Research Centre (IDRC) Digital Library (Canada)

    afin d'y favoriser la croissance et le développement. Il en résulte des solutions locales, novatrices et durables, qui offrent des choix aux personnes qui en ont le plus besoin et font changer les choses. Centre de recherches pour le développement international. CP 8500, Ottawa (Ontario) Canada K1G 3H9. 1012 alexandrie.

  6. Honduras | CRDI - Centre de recherches pour le développement ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Honduras. Le CRDI appuie des chercheurs honduriens depuis 1978. Les premiers travaux ont porté sur l'amélioration des cultures et des systèmes culturaux. Les techniques qui en ont résulté ont accru les rendements des cultures vivrières de base et des cultures de rapport, et les agriculteurs les ont rapidement adoptées.

  7. Asie | CRDI - Centre de recherches pour le développement ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    ... défis agricoles, environnementaux, technologiques, sociaux et économiques de l'Asie. Grâce à nos investissements stratégiques, nous aidons les acteurs régionaux à participer plus efficacement à résolution des problèmes régionaux. Qu'en résulte-t-il ? Des dirigeants régionaux forts, pour aujourd'hui et pour demain.

  8. Effects of Anti-G Measures on Gas Exchange.

    Science.gov (United States)

    1981-05-01

    position (+lGz), and the endotracheal tube was connected to a Rudolf valve arranged so that expired gas passed through a heated pneumotachograph and a... Steiner , 1960; Peterson, Bishop and Erickson, 1977). Data presented in Table 111-I suggest that application of the G-sult abdominal bladder tended to...accelerations. Aerospace Med. 31: 213-219, 1960. 18. Hershgold, E.J. and S.H. Steiner . Cardiovascular changes during acceleration stress in dogs. J

  9. Enzymatic sulfation of tocopherols and tocopherol metabolites by human cytosolic sulfotransferases.

    Science.gov (United States)

    Hashiguchi, Takuyu; Kurogi, Katsuhisa; Sakakibara, Yoichi; Yamasaki, Masao; Nishiyama, Kazuo; Yasuda, Shin; Liu, Ming-Cheh; Suiko, Masahito

    2011-01-01

    Tocopherols are essential micronutrients for mammals widely known as potent lipid-soluble antioxidants that are present in cell membranes. Recent studies have demonstrated that most of the carboxychromanol (CEHC), a tocopherol metabolite, in the plasma exists primarily in sulfate- and glucuronide-conjugated forms. To gain insight into the enzymatic sulfation of tocopherols and their metabolites, a systematic investigation was performed using all 14 known human cytosolic sulfotransferases (SULTs). The results showed that the members of the SULT1 family displayed stronger sulfating activities toward tocopherols and their metabolites. These enzymes showed a substrate preference for γ-tocopherol over α-tocopherol and for γ-CEHC over other CEHCs. Using A549 human lung epithelial cells in a metabolic labeling study, a similar trend in the sulfation of tocopherols and CEHCs was observed. Collectively, the results obtained indicate that SULT-mediated enzymatic sulfation of tocopherols and their metabolites is a significant pathway for regulation of the homeostasis and physiological functions of these important compounds.

  10. Novel enzymatic assay predicts minoxidil response in the treatment of androgenetic alopecia.

    Science.gov (United States)

    Goren, Andy; Castano, Juan Antonio; McCoy, John; Bermudez, Fernando; Lotti, Torello

    2014-01-01

    Topical minoxidil is the most common drug used for the treatment of androgenetic alopecia (AGA) in men and women. Although topical minoxidil exhibits a good safety profile, the efficacy in the overall population remains relatively low at 30-40%. To observe significant improvement in hair growth, minoxidil is typically used daily for a period of at least 3-4 months. Due to the significant time commitment and low response rate, a biomarker for predicting patient response prior to therapy would be advantageous. Minoxidil is converted in the scalp to its active form, minoxidil sulfate, by the sulfotransferase enzyme SULT1A1. We hypothesized that SULT1A1 enzyme activity in the hair follicle correlates with minoxidil response for the treatment of AGA. Our preliminary retrospective study of a SULT1A1 activity assay demonstrates 95% sensitivity and 73% specificity in predicting minoxidil treatment response for AGA. A larger prospective study is now under way to further validate this novel assay. © 2013 Wiley Periodicals, Inc.

  11. The liver transcriptome of suckermouth armoured catfish (Pterygoplichthys anisitsi, Loricariidae): Identification of expansions in defensome gene families

    International Nuclear Information System (INIS)

    Parente, Thiago E.; Moreira, Daniel A.; Magalhães, Maithê G.P.; Andrade, Paula C.C. de; Furtado, Carolina; Haas, Brian J.; Stegeman, John J.; Hahn, Mark E.

    2017-01-01

    Pterygoplichthys is a genus of related suckermouth armoured catfishes native to South America, which have invaded tropical and subtropical regions worldwide. Physiological features, including an augmented resistance to organic xenobiotics, may have aided their settlement in foreign habitats. The liver transcriptome of Pterygoplichthys anisitsi was sequenced and used to characterize the diversity of mRNAs potentially involved in the responses to natural and anthropogenic chemicals. In total, 66,642 transcripts were assembled. Among the identified defensome genes, cytochromes P450 (CYP) were the most abundant, followed by sulfotransferases (SULT), nuclear receptors (NR) and ATP binding cassette transporters (ABC). A novel expansion in the CYP2Y subfamily was identified, as well as an independent expansion of the CYP2AAs. Two expansions were also observed among SULT1. Thirty-two transcripts were classified into twelve subfamilies of NR, while 21 encoded ABC transporters. The diversity of defensome transcripts sequenced herein could contribute to this species' resistance to organic xenobiotics. - Highlights: • Resistance of P. anisitsi to organic pollutants (e.g. Diesel oil) is elevated. • > 60 thousand transcripts were assembled at high sequencing depth. • > 20 thousand transcripts were annotated using UniProt and GO databases. • Complete coding sequence for 183 defensome transcripts were identified. • Most abundant defensome families were P450 followed by SULT, NR and ABC transporters.

  12. Doença de Krabbe — A Propósito de Dois Casos Clínicos

    OpenAIRE

    Sampaio, Virgínia; Belo, Emília; Frutuoso, Simão; Cerqueira, Rui; Mendanha, Sérgio; Maciel, Idalina

    2014-01-01

    A doença de Krabbe também designada por leucodistrofia de células globoides é uma doença autossómica recessiva rara causada por um déficede um enzima, o galactosilceramidase. Os autores apresentam dois casos clínicos da forma de apresentação desta leucodistrofia no lactente.

  13. ESTUDIO DE LAS PROPIEDADES FISICOQUIMICAS DE LA LAMELA Y SU INFLUENCIA EN LA ESTRUCTURA SECUNDARIA Y EN LA ACTIVIDAD ATPASICA SECUNDARIA DE Na,K-ATPasa RECONSTITUIDA EN MODELOS DE MEMBRANAS.

    OpenAIRE

    CUEVAS CORTES, FRANCISCO JAVIER; CUEVAS CORTES, FRANCISCO JAVIER

    2005-01-01

    En la presente tesis se planteó el problema de correlacionar el efecto de variaciones del contenido de colesterol de la membrana sobre la actividad de la enzima, con los cambios en las propiedades de dominios específicos de la lamela. Debido a la alta com 131p.

  14. Utilização do trigo e do centeio na alimentação do frango de carne

    OpenAIRE

    Mourão, J.L

    2001-01-01

    Estudo realizado a fim de conhecer os efeitos do centeio e da sua suplementação com xilanases nas performances de crescimento do frango de carne. A centeio afetou negativamente os resultados mas os enzimas não tiveram efeitos evidentes.

  15. Efecto de la incorporación de transglutaminasa microbiana en las propiedades sensoriales de hamburguesas de desmenuzado de merluza (Merluccius hubbsi

    Directory of Open Access Journals (Sweden)

    Alicia Panuncio

    2013-12-01

    Full Text Available Se elaboraron hamburguesas de pescado a partir de desmenuzado de merluza (Merluccius hubbsi con la incorporación de transglutaminasa microbiana, con la finalidad de mejorar sus propiedades sensoriales y elaborar un producto pesquero que fomente el consumo de pescado en Uruguay. Se evaluó desde el punto de vista sensorial y de textura instrumental el efecto del agregado de la enzima en la formulación de las hamburguesas. Se elaboraron tres tipos de hamburguesas: sin enzima y con incorporación de 0,5% y 1,0% de enzima transglutaminasa, respectivamente. Para la evaluación sensorial se analizaron las muestras con un panel de seis jueces entrenados y para la determinación de los parámetros de textura instrumental se utilizó un analizador de textura TA.XT2i. Los resultados de ambos estudios indicaron que el agregado de enzima mejoró sustancialmente la apariencia, la textura y el sabor del producto. Se obtuvo un producto pesquero innovador, con características que pueden resultar muy atractivas para el consumidor uruguayo.

  16. Influencia de la transglutaminasa en el rendimiento de la producción de queso dambo uruguayo

    Directory of Open Access Journals (Sweden)

    Daniela Escobar

    2014-12-01

    Full Text Available El queso dambo uruguayo es un queso de mediana humedad de origen danés con formulación modificada. Esta investigación estudió el uso de la enzima transglutaminasa en la producción de queso dambo tipo barra para aumentar el rendimiento del proceso.Se fabricaron quesos aplicando un diseño experimental completamente al azar con parcelas divididas medidas en el tiempo, considerando dos factores (concentración de la enzima y momento de agregado en tres niveles, por triplicado, tomando como referencia el queso sin enzima.Los quesos fueron analizados a lo largo de cuatro meses en peso, pH, contenido de proteínas, humedad y materia grasa. Se calculó el rendimiento relativo al queso referencia, la recuperación de extracto seco y el contenido en proteínas y materia grasa en el queso respecto a la leche. Se analizó el perfil de textura y se determinaron las propiedades sensoriales con un panel de jueces entrenados.Los resultados mostraron que la única condición con diferencia significativa al 5% en el rendimiento relativo fue el momento de agregado de la enzima, resultando como momento óptimo la incorporación de la misma junto con el cuajo, independientemente de la dosis utilizada. El rendimiento logrado fue un 6% superior al queso referencia. 

  17. PRODUÇÃO DE BIODIESEL POR BIOCATÁLISE UTILIZANDO MÉTODO ALTERNATIVO DE IMOBILIZAÇÃO DA LIPASE EM HIDROGEL

    Directory of Open Access Journals (Sweden)

    Fernanda Marder

    2008-12-01

    Full Text Available A sociedade vem buscando alternativas para reduzir o processo de destruição ambiental instalada no planeta, porém, a partirdo século passado, uma nova visão sobre o uso indiscriminado dos recursos ambientais passou a ser discutido levando a utilizaçãode tecnologias alternativas de produção de combustíveis mais limpos, como o biodiesel, produzido a partir de óleos vegetais. Osprocessos enzimáticos constituem-se numa alternativa de produção, por serem métodos biotecnológicos e menos impactantes aomeio ambiente, apresentando até então, elevado custo de produção. Com o objetivo de diminuir custos e aumentar a eficiênciainvestigou-se a imobilização das enzimas por método alternativo e o emprego destes biocatalisadores na produção de biodiesel. Aimobilização da lipase PS Amano foi realizada utilizando esferas formadas pela hidratação de hidrogéis comerciais em soluçãoaquosa contendo a enzima. Com a enzima imobilizada realizou-se a transesterificação, na qual obteve-se conversões em ésteresmetílicos com rendimento de até 70%, em solvente orgânico, no tempo de 24h, temperatura de 55°C, 100 rpm e 40 esferas dehidrogel com enzima imobilizada. O método de transesterificação enzimática com as enzimas imobilizadas em hidrogéisapresentou-se como uma tecnologia alternativa e promissora para a obtenção de biodiesel.

  18. Nonhemocyte sources of selected lysosomal enzymes in Biomphalaria glabrata, B. tenagophila and B. straminea (Mollusca: Pulmonata

    Directory of Open Access Journals (Sweden)

    Gary E. Rodrick

    1981-09-01

    Full Text Available The specific activities of acid phosphatase, alkaline phosphatase, β-glucuronidase, lysozymes, glutamate-oxalacetate transaminase and glutamate-pyruvate transaminate were determined in the head-foot and digestive gland of Brazilian Biomphalaria glabrata (Touros, B. tenagophila (Caçapava and B. straminea (Monsenhor Gil. All six enzymes were detected inthe 3000g supernatant. Both cytoplasmic enzymes, glutamate-oxalacetate and glutamate-pyruvate transaminase exhibited the highest specific activities. In the case of the four hydrolytic enzymes assayed, β-glucuronidase exhibited the highest specific activity while lysozyme showed the lowest activity. All six enzymes are thought to be produced by cells within the head-foot and digestive gland of B. glabrata, B. tenagophila and B. straminea.Foram determinadas, na massa cefalopedal e na glândula digestiva de Biomphalaria glabrata de Touros (Rio Grande do Norte B. tenagophila de Cacapava (Sao Paulo e B. straminea de Monsenhor Gil (Piauí, as atividades específicas das seguintes enzimas: fosfatase acida, fosfatase alcalina, beta-glucuronidase, lisozima, transaminase glutâmico-oxalacetica e transaminase glutâmico-piruvica. As seis enzimas referidas foram detectadas no sobrenadante a 3000g. Ambas as enzimas citoplasmaticas - transaminases glutamico-oxalacetica e glutamico-piruvica - mostraram as atividades específicas mais altas. No caso das quatro enzimas hidrolíticas, a beta-glucuronidase revelou a mais alta atividade específica, enquanto a lisozima revelou a mais baixa. E admitido que todas as seis enzimas sao produzidas por celulas presentes na massa cefalopedal e na glândula digestiva das tres especies de moluscos examinadas.

  19. Genome-Wide Identification, Characterization, and Expression Profiling of Glutathione S-Transferase (GST) Family in Pumpkin Reveals Likely Role in Cold-Stress Tolerance

    Science.gov (United States)

    Abdul Kayum, Md.; Nath, Ujjal Kumar; Park, Jong-In; Choi, Eung Kyoo; Song, Jae-Young; Kim, Hoy-Taek; Nou, Ill-Sup

    2018-01-01

    Plant growth and development can be adversely affected by cold stress, limiting productivity. The glutathione S-transferase (GST) family comprises important detoxifying enzymes, which play major roles in biotic and abiotic stress responses by reducing the oxidative damage caused by reactive oxygen species. Pumpkins (Cucurbita maxima) are widely grown, economically important, and nutritious; however, their yield can be severely affected by cold stress. The identification of putative candidate genes responsible for cold-stress tolerance, including the GST family genes, is therefore vital. For the first time, we identified 32 C. maxima GST (CmaGST) genes using a combination of bioinformatics approaches and characterized them by expression profiling. These CmaGST genes represent seven of the 14 known classes of plant GSTs, with 18 CmaGSTs categorized into the tau class. The CmaGSTs were distributed across 13 of pumpkin’s 20 chromosomes, with the highest numbers found on chromosomes 4 and 6. The large number of CmaGST genes resulted from gene duplication; 11 and 5 pairs of CmaGST genes were segmental- and tandem-duplicated, respectively. In addition, all CmaGST genes showed organ-specific expression. The expression of the putative GST genes in pumpkin was examined under cold stress in two lines with contrasting cold tolerance: cold-tolerant CP-1 (C. maxima) and cold-susceptible EP-1 (Cucurbita moschata). Seven genes (CmaGSTU3, CmaGSTU7, CmaGSTU8, CmaGSTU9, CmaGSTU11, CmaGSTU12, and CmaGSTU14) were highly expressed in the cold-tolerant line and are putative candidates for use in breeding cold-tolerant crop varieties. These results increase our understanding of the cold-stress-related functions of the GST family, as well as potentially enhancing pumpkin breeding programs. PMID:29439434

  20. Are glutathione S transferases involved in DNA damage signalling? Interactions with DNA damage and repair revealed from molecular epidemiology studies

    Energy Technology Data Exchange (ETDEWEB)

    Dusinska, Maria, E-mail: Maria.DUSINSKA@nilu.no [CEE-Health Effects Group, NILU - Norwegian Institute for Air Research, Kjeller (Norway); Staruchova, Marta; Horska, Alexandra [Department of Experimental and Applied Genetics, Slovak Medical University, Bratislava (Slovakia); Smolkova, Bozena [Laboratory of Cancer Genetics, Cancer Research Institute of the Slovak Academy of Sciences, Bratislava (Slovakia); Collins, Andrew [Department of Nutrition, Faculty of Medicine, University of Oslo (Norway); Bonassi, Stefano [Unit of Clinical and Molecular Epidemiology, IRCCS San Raffaele Pisana, Rome (Italy); Volkovova, Katarina [Department of Experimental and Applied Genetics, Slovak Medical University, Bratislava (Slovakia)

    2012-08-01

    Glutathione S-transferases (GSTs) are members of a multigene family of isoenzymes that are important in the control of oxidative stress and in phase II metabolism. Acting non-enzymically, GSTs can modulate signalling pathways of cell proliferation, cell differentiation and apoptosis. Using a molecular epidemiology approach, we have investigated a potential involvement of GSTs in DNA damage processing, specifically the modulation of DNA repair in a group of 388 healthy adult volunteers; 239 with at least 5 years of occupational exposure to asbestos, stone wool or glass fibre, and 149 reference subjects. We measured DNA damage in lymphocytes using the comet assay (alkaline single cell gel electrophoresis): strand breaks (SBs) and alkali-labile sites, oxidised pyrimidines with endonuclease III, and oxidised purines with formamidopyrimidine DNA glycosylase. We also measured GST activity in erythrocytes, and the capacity for base excision repair (BER) in a lymphocyte extract. Polymorphisms in genes encoding three GST isoenzymes were determined, namely deletion of GSTM1 and GSTT1 and single nucleotide polymorphism Ile105Val in GSTP1. Consumption of vegetables and wine correlated negatively with DNA damage and modulated BER. GST activity correlated with oxidised bases and with BER capacity, and differed depending on polymorphisms in GSTP1, GSTT1 and GSTM1. A significantly lower BER rate was associated with the homozygous GSTT1 deletion in all asbestos site subjects and in the corresponding reference group. Multifactorial analysis revealed effects of sex and exposure in GSTP1 Ile/Val heterozygotes but not in Ile/Ile homozygotes. These variants affected also SBs levels, mainly by interactions of GSTP1 genotype with exposure, with sex, and with smoking habit; and by an interaction between sex and smoking. Our results show that GST polymorphisms and GST activity can apparently influence DNA stability and repair of oxidised bases, suggesting a potential new role for these

  1. Does maternal exposure to artificial food coloring additives increase oxidative stress in the skin of rats?

    Science.gov (United States)

    Başak, K; Başak, P Y; Doğuç, D K; Aylak, F; Oğuztüzün, S; Bozer, B M; Gültekin, F

    2017-10-01

    Glutathione-S-transferase (GST) and cytochrome P450 family 1 subfamily A polypeptide 1 (CYP1A1) metabolize and detoxify carcinogens, drugs, environmental pollutants, and reactive oxygen species. Changes of GST expression in tissues and gene mutations have been reported in association with many neoplastic skin diseases and dermatoses. Widely used artificial food coloring additives (AFCAs) also reported to effect primarily behavioral and cognitive function and cause neoplastic diseases and several inflammatory skin diseases. We aimed to identify the changes in expression of GSTs, CYP1A1, and vascular endothelial growth factor (VEGF) in rat skin which were maternally exposed AFCAs. A rat model was designed to evaluate the effects of maternal exposure of AFCAs on skin in rats. "No observable adverse effect levels" of commonly used AFCAs as a mixture were given to female rats before and during gestation. Immunohistochemical expression of GSTs, CYP1A1, and VEGF was evaluated in their offspring. CYP1A1, glutathione S-transferase pi (GSTP), glutathione S-transferase alpha (GSTA), glutathione S-transferase mu (GSTM), glutathione S-transferase theta (GSTT), and VEGF were expressed by epidermal keratinocytes, dermal fibroblasts, sebaceous glands, hair follicle, and subcutaneous striated muscle in the normal skin. CYP1A1, GSTA, and GSTT were expressed at all microanatomical sites of skin in varying degrees. The expressions of CYP1A1, GSTA, GSTT, and VEGF were decreased significantly, while GSTM expression on sebaceous gland and hair follicle was increased. Maternal exposure of AFCAs apparently effects expression of the CYP1A1, GSTs, and VEGF in the skin. This prominent change of expressions might play role in neoplastic and nonneoplastic skin diseases.

  2. Are glutathione S transferases involved in DNA damage signalling? Interactions with DNA damage and repair revealed from molecular epidemiology studies

    International Nuclear Information System (INIS)

    Dusinska, Maria; Staruchova, Marta; Horska, Alexandra; Smolkova, Bozena; Collins, Andrew; Bonassi, Stefano; Volkovova, Katarina

    2012-01-01

    Glutathione S-transferases (GSTs) are members of a multigene family of isoenzymes that are important in the control of oxidative stress and in phase II metabolism. Acting non-enzymically, GSTs can modulate signalling pathways of cell proliferation, cell differentiation and apoptosis. Using a molecular epidemiology approach, we have investigated a potential involvement of GSTs in DNA damage processing, specifically the modulation of DNA repair in a group of 388 healthy adult volunteers; 239 with at least 5 years of occupational exposure to asbestos, stone wool or glass fibre, and 149 reference subjects. We measured DNA damage in lymphocytes using the comet assay (alkaline single cell gel electrophoresis): strand breaks (SBs) and alkali-labile sites, oxidised pyrimidines with endonuclease III, and oxidised purines with formamidopyrimidine DNA glycosylase. We also measured GST activity in erythrocytes, and the capacity for base excision repair (BER) in a lymphocyte extract. Polymorphisms in genes encoding three GST isoenzymes were determined, namely deletion of GSTM1 and GSTT1 and single nucleotide polymorphism Ile105Val in GSTP1. Consumption of vegetables and wine correlated negatively with DNA damage and modulated BER. GST activity correlated with oxidised bases and with BER capacity, and differed depending on polymorphisms in GSTP1, GSTT1 and GSTM1. A significantly lower BER rate was associated with the homozygous GSTT1 deletion in all asbestos site subjects and in the corresponding reference group. Multifactorial analysis revealed effects of sex and exposure in GSTP1 Ile/Val heterozygotes but not in Ile/Ile homozygotes. These variants affected also SBs levels, mainly by interactions of GSTP1 genotype with exposure, with sex, and with smoking habit; and by an interaction between sex and smoking. Our results show that GST polymorphisms and GST activity can apparently influence DNA stability and repair of oxidised bases, suggesting a potential new role for these

  3. Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.

    Science.gov (United States)

    Li, Yingying; Dou, Kai; Gao, Shigang; Sun, Jianan; Wang, Meng; Fu, Kehe; Yu, Chuanjin; Wu, Qiong; Li, Yaqian; Chen, Jie

    2015-08-03

    Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Large-scale determination of sequence, structure, and function relationships in cytosolic glutathione transferases across the biosphere.

    Science.gov (United States)

    Mashiyama, Susan T; Malabanan, M Merced; Akiva, Eyal; Bhosle, Rahul; Branch, Megan C; Hillerich, Brandan; Jagessar, Kevin; Kim, Jungwook; Patskovsky, Yury; Seidel, Ronald D; Stead, Mark; Toro, Rafael; Vetting, Matthew W; Almo, Steven C; Armstrong, Richard N; Babbitt, Patricia C

    2014-04-01

    The cytosolic glutathione transferase (cytGST) superfamily comprises more than 13,000 nonredundant sequences found throughout the biosphere. Their key roles in metabolism and defense against oxidative damage have led to thousands of studies over several decades. Despite this attention, little is known about the physiological reactions they catalyze and most of the substrates used to assay cytGSTs are synthetic compounds. A deeper understanding of relationships across the superfamily could provide new clues about their functions. To establish a foundation for expanded classification of cytGSTs, we generated similarity-based subgroupings for the entire superfamily. Using the resulting sequence similarity networks, we chose targets that broadly covered unknown functions and report here experimental results confirming GST-like activity for 82 of them, along with 37 new 3D structures determined for 27 targets. These new data, along with experimentally known GST reactions and structures reported in the literature, were painted onto the networks to generate a global view of their sequence-structure-function relationships. The results show how proteins of both known and unknown function relate to each other across the entire superfamily and reveal that the great majority of cytGSTs have not been experimentally characterized or annotated by canonical class. A mapping of taxonomic classes across the superfamily indicates that many taxa are represented in each subgroup and highlights challenges for classification of superfamily sequences into functionally relevant classes. Experimental determination of disulfide bond reductase activity in many diverse subgroups illustrate a theme common for many reaction types. Finally, sequence comparison between an enzyme that catalyzes a reductive dechlorination reaction relevant to bioremediation efforts with some of its closest homologs reveals differences among them likely to be associated with evolution of this unusual reaction

  5. Large-scale determination of sequence, structure, and function relationships in cytosolic glutathione transferases across the biosphere.

    Directory of Open Access Journals (Sweden)

    Susan T Mashiyama

    2014-04-01

    Full Text Available The cytosolic glutathione transferase (cytGST superfamily comprises more than 13,000 nonredundant sequences found throughout the biosphere. Their key roles in metabolism and defense against oxidative damage have led to thousands of studies over several decades. Despite this attention, little is known about the physiological reactions they catalyze and most of the substrates used to assay cytGSTs are synthetic compounds. A deeper understanding of relationships across the superfamily could provide new clues about their functions. To establish a foundation for expanded classification of cytGSTs, we generated similarity-based subgroupings for the entire superfamily. Using the resulting sequence similarity networks, we chose targets that broadly covered unknown functions and report here experimental results confirming GST-like activity for 82 of them, along with 37 new 3D structures determined for 27 targets. These new data, along with experimentally known GST reactions and structures reported in the literature, were painted onto the networks to generate a global view of their sequence-structure-function relationships. The results show how proteins of both known and unknown function relate to each other across the entire superfamily and reveal that the great majority of cytGSTs have not been experimentally characterized or annotated by canonical class. A mapping of taxonomic classes across the superfamily indicates that many taxa are represented in each subgroup and highlights challenges for classification of superfamily sequences into functionally relevant classes. Experimental determination of disulfide bond reductase activity in many diverse subgroups illustrate a theme common for many reaction types. Finally, sequence comparison between an enzyme that catalyzes a reductive dechlorination reaction relevant to bioremediation efforts with some of its closest homologs reveals differences among them likely to be associated with evolution of this

  6. Differential roles for VviGST1, VviGST3 and VviGST4 in proanthocyanidin and anthocyanin transport in Vitis vinífera

    Directory of Open Access Journals (Sweden)

    Ricardo Pérez-Díaz

    2016-08-01

    Full Text Available In plant cells, flavonoids are synthesized in the cytosol and then are transported and accumulated in the vacuole. Glutathione S-transferase-mediated transport has been proposed as a mechanism involved in flavonoid transport however whether binding of flavonoids to GST or their transport is glutathione-dependent is not well understood. Glutathione S-transferases from Vitis vinífera (VviGSTs have been associated with the transport of anthocyanins, however their ability to transport other flavonoids such as proanthocyanidins (PAs has not been established. Following bioinformatics approaches, we analyzed the capability of VviGST1, VviGST3, VviGST4 and Arabidopsis TT19 to bind different flavonoids. Analyses of protein-ligand interactions indicate that these GSTs can bind glutathione and monomers of anthocyanin, PAs and flavonols. A total or partial overlap of the binding sites for glutathione and flavonoids was found in VviGST1, and a similar condition was observed in VviGST3 using anthocyanin and flavonols as ligands, whereas VviGST4 and TT19 have both sites for GSH and flavonoids separated. To validate the bioinformatics predictions, functional complementation assays using the Arabidopsis tt19 mutant were performed. Overexpression of VviGST3 in tt19-1 specifically rescued the dark seed coat phenotype associated to correct PA transport, which correlated with higher binding affinity for PA precursors. VviGST4, originally characterized as an anthocyanin-related GST, complemented both the anthocyanin and PA deposition, resembling the function of TT19. By contrast, VviGST1 only partially rescued the normal seed color. Furthermore the expression pattern of these VviGSTs showed that each of these genes could be associated with the accumulation of different flavonoids in specific tissues during grapevine fruit development. These results provide new insights into GST-mediated PA transport in grapevine and suggest that VviGSTs present different

  7. Differential Roles for VviGST1, VviGST3, and VviGST4 in Proanthocyanidin and Anthocyanin Transport in Vitis vinífera.

    Science.gov (United States)

    Pérez-Díaz, Ricardo; Madrid-Espinoza, José; Salinas-Cornejo, Josselyn; González-Villanueva, Enrique; Ruiz-Lara, Simón

    2016-01-01

    In plant cells, flavonoids are synthesized in the cytosol and then are transported and accumulated in the vacuole. Glutathione S-transferase-mediated transport has been proposed as a mechanism involved in flavonoid transport, however, whether binding of flavonoids to glutathione S-transferase (GST) or their transport is glutathione-dependent is not well understood. Glutathione S-transferases from Vitis vinífera (VviGSTs) have been associated with the transport of anthocyanins, however, their ability to transport other flavonoids such as proanthocyanidins (PAs) has not been established. Following bioinformatics approaches, we analyzed the capability of VviGST1, VviGST3, VviGST4, and Arabidopsis TT19 to bind different flavonoids. Analyses of protein-ligand interactions indicate that these GSTs can bind glutathione and monomers of anthocyanin, PAs and flavonols. A total or partial overlap of the binding sites for glutathione and flavonoids was found in VviGST1, and a similar condition was observed in VviGST3 using anthocyanin and flavonols as ligands, whereas VviGST4 and TT19 have both sites for GSH and flavonoids separated. To validate the bioinformatics predictions, functional complementation assays using the Arabidopsis tt19 mutant were performed. Overexpression of VviGST3 in tt19-1 specifically rescued the dark seed coat phenotype associated to correct PA transport, which correlated with higher binding affinity for PA precursors. VviGST4, originally characterized as an anthocyanin-related GST, complemented both the anthocyanin and PA deposition, resembling the function of TT19. By contrast, VviGST1 only partially rescued the normal seed color. Furthermore the expression pattern of these VviGSTs showed that each of these genes could be associated with the accumulation of different flavonoids in specific tissues during grapevine fruit development. These results provide new insights into GST-mediated PA transport in grapevine and suggest that VviGSTs present

  8. Human glutathione transferases catalyzing the bioactivation of anticancer thiopurine prodrugs.

    Science.gov (United States)

    Eklund, Birgitta I; Gunnarsdottir, Sjofn; Elfarra, Adnan A; Mannervik, Bengt

    2007-06-01

    cis-6-(2-Acetylvinylthio)purine (cAVTP) and trans-6-(2-acetylvinylthio)guanine (tAVTG) are thiopurine prodrugs provisionally inactivated by an alpha,beta-unsaturated substituent on the sulfur of the parental thiopurines 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG). The active thiopurines are liberated intracellularly by glutathione (GSH) in reactions catalyzed by glutathione transferases (GSTs) (EC 2.5.1.18). Catalytic activities of 13 human GSTs representing seven distinct classes of soluble GSTs have been determined. The bioactivation of cAVTP and tAVTG occurs via a transient addition of GSH to the activated double bond of the S-substituent of the prodrug, followed by elimination of the thiopurine. The first of these consecutive reactions is rate-limiting for thiopurine release, but GST-activation of this first addition is shifting the rate limitation to the subsequent elimination. Highly active GSTs reveal the transient intermediate, which is detectable by UV spectroscopy and HPLC analysis. LC/MS analysis of the reaction products demonstrates that the primary GSH conjugate, 4-glutathionylbuten-2-one, can react with a second GSH molecule to form the 4-(bis-glutathionyl)butan-2-one. GST M1-1 and GST A4-4 were the most efficient enzymes with tAVTG, and GST M1-1 and GST M2-2 had highest activity with cAVTP. The highly efficient GST M1-1 is polymorphic and is absent in approximately half of the human population. GST P1-1, which is overexpressed in many cancer cells, had no detectable activity with cAVTP and only minor activity with tAVTG. Other GST-activated prodrugs have targeted GST P1-1-expressing cancer cells. Tumors expressing high levels of GST M1-1 or GST A4-4 can be predicted to be particularly vulnerable to chemotherapy with cAVTP or tAVTG.

  9. Observational tests of the Electro-Magnetic Black Hole Theory in Gamma-Ray Bursts

    OpenAIRE

    Ruffini, Remo

    2002-01-01

    The Relative Space-Time Transformation (RSTT) Paradigm and the Interpretation of the Burst Structure (IBS) Paradigm are applied to the analysis of the structure of the burst and afterglow of Gamma-Ray Bursts within the theory based on the vacuum polarization process occurring in an Electro-Magnetic Black Hole, the EMBH theory. This framework is applied to the study of the GRB991216 which is used as a prototype. The GRB-Supernova Time Sequence (GSTS) Paradigm, which introduces the concept of i...

  10. Photoaffinity labelling of the active site of the rat glutathione transferases 3-3 and 1-1 and human glutathione transferase A1-1.

    OpenAIRE

    Cooke, R J; Björnestedt, R; Douglas, K T; McKie, J H; King, M D; Coles, B; Ketterer, B; Mannervik, B

    1994-01-01

    The glutathione transferases (GSTs) form a group of enzymes responsible for a wide range of molecular detoxications. The photoaffinity label S-(2-nitro-4-azidophenyl)glutathione was used to study the hydrophobic region of the active site of the rat liver GST 1-1 and 2-2 isoenzymes (class Alpha) as well as the rat class-Mu GST 3-3. Photoaffinity labelling was carried out using a version of S-(2-nitro-4-azidophenyl)glutathione tritiated in the arylazido ring. The labelling occurred with higher ...

  11. Antioxidant role of glutathione S-transferases: 4-Hydroxynonenal, a key molecule in stress-mediated signaling

    International Nuclear Information System (INIS)

    Singhal, Sharad S.; Singh, Sharda P.; Singhal, Preeti; Horne, David; Singhal, Jyotsana; Awasthi, Sanjay

    2015-01-01

    4-Hydroxy-2-trans-nonenal (4HNE), one of the major end products of lipid peroxidation (LPO), has been shown to induce apoptosis in a variety of cell lines. It appears to modulate signaling processes in more than one way because it has been suggested to have a role in signaling for differentiation and proliferation. It has been known that glutathione S-transferases (GSTs) can reduce lipid hydroperoxides through their Se-independent glutathione-peroxidase activity and that these enzymes can also detoxify LPO end-products such as 4HNE. Available evidence from earlier studies together with results of recent studies in our laboratories strongly suggests that LPO products, particularly hydroperoxides and 4HNE, are involved in the mechanisms of stress-mediated signaling and that it can be modulated by the alpha-class GSTs through the regulation of the intracellular concentrations of 4HNE. We demonstrate that 4HNE induced apoptosis in various cell lines is accompanied with c-Jun-N-terminal kinase (JNK) and caspase-3 activation. Cells exposed to mild, transient heat or oxidative stress acquire the capacity to exclude intracellular 4HNE at a faster rate by inducing GSTA4-4 which conjugates 4HNE to glutathione (GSH), and RLIP76 which mediates the ATP-dependent transport of the GSH-conjugate of 4HNE (GS-HNE). The balance between formation and exclusion promotes different cellular processes — higher concentrations of 4HNE promote apoptosis; whereas, lower concentrations promote proliferation. In this article, we provide a brief summary of the cellular effects of 4HNE, followed by a review of its GST-catalyzed detoxification, with an emphasis on the structural attributes that play an important role in the interactions with alpha-class GSTA4-4. Taken together, 4HNE is a key signaling molecule and that GSTs being determinants of its intracellular concentrations, can regulate stress-mediated signaling, are reviewed in this article. - Highlights: • GSTs are the major

  12. Pretreatment of cottonseed flakes with proteases and an amylase for higher oil yields

    Directory of Open Access Journals (Sweden)

    Hassanein, Minar M.

    2007-09-01

    Full Text Available The effect of enzymatic pretreatment of cottonseed flakes on oil extractability was studied. The enzymes investigated included bacterial protease (Bp, papain (Pa, savinase (S, termamyl (T, pectinase (Pe and cellulase (C. The variables studied during the enzymatic hydrolysis experiments were: enzyme concentration, moisture: cottonseed flakes ratio, and time of hydrolysis. Enzymatic hydrolysis experiments were first carried out with a single enzyme, then with enzyme mixtures formulated according to the results of single enzyme treatments. Results were evaluated based on the relative increase in oil extractability, and some oil characteristics in comparison with untreated cottonseed flakes (control. Pretreatment with enzyme mixtures resulted in a relative increase in oil extractability that was higher than single enzyme pretreatment and the control. Statistical analysis showed a significant difference (at 5% level between the control and all enzymatically treated oils as well as among different enzymatically treated oils. The relative increase in oil extractability due to pretreatment with enzyme mixtures were in the following order: S: Pe: Bp>S: P>S: C: Pe>S: Bp>S:T>S: C >S: Pa with values 44.9%, 38.9%, 37.1%, 34.9%, 30.1%, 28.9%, respectively. Enzymatic pretreatment of cottonseed flakes resulted in oils with fatty acid composition, acid value, iodine value and peroxide values that were generally comparable to the control.En este trabajo se estudió el efecto del pretratamiento con enzimas sobre la extractabilidad del aceite en hojuelas de semilla de algodón. Las enzimas que se investigaron fueron proteasa bacteriana (Bp, papaína (Pa, savinasa (S, temamil (T, pectinasa (Pe y celulasa (C. Las variables estudiadas durante los experimentos de hidrólisis enzimática fueron: concentración de la enzima, ratio humedad:cantidad de hojuelas y tiempo de hidrólisis. Estos experimentos se realizaron primeramente con una sola enzima y posteriormente con

  13. EFEITOS DO pH, SAL E DESNATURANTES NA HIDRÓLISE IN VITRO DA GLOBULINA PRINCIPAL DE GRÃO-DE-BICO (Cicer arietinum L., var. IAC-Marrocos*

    Directory of Open Access Journals (Sweden)

    V. A. NEVES

    2009-03-01

    Full Text Available

    As leguminosas caracterizam-se por apresentar alto teor protéico que na sua grande totalidade são globulinas de reserva,e cujas características moleculares influenciam algumas de suas propriedades com destaque para sua hidrólise frente às enzimas digestivas. As frações 7 e 11S, apesar de certa homologia estrutural, surgem como determinantes das propriedades nutritivas e funcionais das globulinas. Nesse trabalho a globulina principal de grão-de-bico (tipo legumina, 11S foi isolada e purificada, verificando-se o efeito da exposição a diferentes fatores na hidrólise in vitro com as enzimas tripsina e quimotripsina. Comparada à caseína, a globulina principal na forma nativa, e na presença de NaCl 0,3 M, mostrou-se menos susceptível à hidrólise pelas enzimas. A exposição a pHs ácidos extremos revela a retirada desse efeito protetor observado com o sal. As maiores alterações ocorreram pela exposição ao pH 1,0, temperatura de 121°C/15 min e presença de NaCl, no entanto ainda inferiores aos obtidos com a caseína e para ambas enzimas. O tratamento alcalino apesar de aumentar a susceptibilidade às enzimas mostrou valores de hidrólise inferiores à caseína. A exposição a diferentes concentrações dos desnaturantes uréia e hidrocloreto de guanidínio revelou que apenas o segundo teve pequeno efeito sobre a hidrólise pelas enzimas e, mesmo assim, em concentração tão alta como 8M. PALAVRAS-CHAVE: Grão-de-bico; Cicer arietinum L; globulina principal; hidrólise in vitro.

  14. Purificação de três diferentes beta-galactosidades microbianas por partição em sistemas de duas fases aquosas Purification of three different microbial beta-galactosidases by partitioning in aqueous two-phase systems

    Directory of Open Access Journals (Sweden)

    Maria Estela SILVA

    1997-12-01

    Full Text Available Este trabalho tratou da investigação do efeito do peso molecular de polietilenoglicol (PEG sobre a partição de enzimas beta-galactosidases de diferentes origens microbianas: Escherichia coli, Klueveromyces lactis e Aspergillus orizae em sistemas de duas fases aquosas (SDFA.Foi observado que os melhores sistemas para purificação da enzima de E. coli foram os formados por PEG 4000, 6000 e 8000/fosfato, fornecendo os mais elevados fatores de purificação da enzima. As enzimas de Klueveromyces lactis e Aspergillus orizae não foram eficientemente purificadas nestes sistemas sendo insensíveis à alterações do peso molecular do PEG. Portanto, um outro sistema de duas fases aquosas foi desenvolvido contendo um ligante específico, p-aminofenil 1-tio-beta-D-galactopiranosídeo (APGP, acoplado ao PEG para purificar a enzima de Klueveromyces lactis. Uma etapa simples de partição no SDFA formado por 6% APGP-PEG4000 + 12% dextrana T505.000 foi capaz de recuperar 83% da enzima na fase superior do sistema e de aumentar 1,6 vezes o fator de purificação.This work investigated the effect of the molecular weight of polyethyleneglycol (PEG upon the partition coefficient of beta-galactosidases from three different microorganisms: Escherichia coli, Klueveromyces lactis and Aspergillus orizae. It was found that PEG 6,000 and PEG 8,000/phosphate were the best systems for achieving the highest purification factors of E. coli beta-galactosidase. However, the other two yeast beta-galactosidases were not efficiently separated from their contaminants in any of the PEG/salt systems. In order to improve the separation of Klueveromyces lactis beta-galactosidase from the main protein contaminants, the biospecific ligand p-aminophenyl 1-thio-beta-D-galactopyranoside (APGP was attached to activated PEG 4000. The affinity PEG having APGP bound to its backbone was synthesized in two steps. The partitioning of Klueveromyces lactis beta-galactosidase in aqueous two

  15. PURIFICACIÓN Y CARACTERIZACIÓN DE alfa-AMILASA DE PENICILLIUM COMMUNE PRODUCIDA MEDIANTE FERMENTACIÓN EN FASE SÓLIDA

    Directory of Open Access Journals (Sweden)

    Esperanza Espinel

    2010-03-01

    Full Text Available Este estudio reporta la purificación y caracterización parcial de una alfa-amilasa producida por Penicillium commune mediante fermentación en fase sólida, empleandoyuca blanca colombiana (Manihot esculenta Crantz como soporte. La enzima fue purificada por precipitación fraccionada con sulfato de amonio, cromatografía de intercambio aniónico (DEAE-Sephadex A-50, cromatografía de filtración por gel (Sephadex G-75 y cromatografía de intercambio catiónico (CM-Sephadex C-50 obteniendo una actividad específica final de 314,82 U/mg, un grado de purificación del orden de 62 y un rendimiento de 9%. La purificación hasta la homogeneidad fue confirmada por SDS-PAGE. El peso molecular estimado fue 35 kDa. La enzima mostró máxima actividad de hidrólisis de almidón soluble con pH 6,0, y estabilidad en un intervalo de pH de 5,0-7,0. La estabilidad térmica de la enzima se presentó en el intervalo de temperatura 0-50 °C y su temperatura óptima fue 70 °C. Los iones Ca2+,Ba2+ y Ag+ aumentaron significativamente la actividad de la enzima, siendo el ión Ca2+ el que tuvo el más alto poder activador. Cu2+ no alteró significativamente la actividad de la enzima, mientras que Li+ y Fe3+ la disminuyeron ligeramente (13%, y Co2+ y Hg2+ la disminuyeron 25% y 40% respectivamente. Los valores de Km y Vmáx fueron calculados usando la linealización de Lineweaver- Burk, con el resultado Km= 0,48 mg/mL y Vmáx = 5,85 micromol glucosa/min. Entre los principales productos de hidrólisis del almidón de yuca se encuentran la maltosa y la glucosa, este resultado proporciona evidencia de que la enzima es capaz de romper los enlaces glicosídicos alfa-1,4 del almidón, comportamiento característico de una alfa-amilasa.

  16. Case-only study of interactions between metabolic enzymes and smoking in colorectal cancer

    International Nuclear Information System (INIS)

    Fan, Chunhong; Jin, Mingjuan; Chen, Kun; Zhang, Yongjing; Zhang, Shuangshuang; Liu, Bing

    2007-01-01

    Gene-gene and gene-environment interactions involved in the metabolism of carcinogens may increase the risk of cancer. Our objective was to measure the interactions between common polymorphisms of P450 (CYP1A2, CYP1B1, CYP2E1), GSTM1 and T1, SULT1A1 and cigarette smoking in colorectal cancer (CRC). A case-only design was conducted in a Chinese population including 207 patients with sporadic CRC. Unconditional logistic regression analysis was performed adjusting for age, gender, alcohol consumption, and cigarette smoking. The interaction odds ratio (COR) for the gene-gene interaction between CYP1B1 1294G and SULT1A1 638A allele was 2.68 (95% CI: 1.16–6.26). The results of the gene-environment analyses revealed that an interaction existed between cigarette smoking and the CYP1B1 1294G allele for CRC (COR = 2.62, 95%CI: 1.01–6.72), the COR for the interaction of CYP1B1 1294G and smoking history > 35 pack-years was 3.47 (95%CI: 1.12–10.80). No other significant gene-gene and gene-environment interactions were observed. Our results showed that the interaction between polymorphisms in CYP1B1 1294G and SULT1A1*2 may play a significant role on CRC in the Chinese population. Also, it is suggested that the association between cigarette smoking and CRC could be differentiated by the CYP1B1 1294G allele

  17. Molecular evolution of Theta-class glutathione transferase for enhanced activity with the anticancer drug 1,3-bis-(2-chloroethyl)-1-nitrosourea and other alkylating agents.

    Science.gov (United States)

    Larsson, Anna-Karin; Shokeer, Abeer; Mannervik, Bengt

    2010-05-01

    Glutathione transferase (GST) displaying enhanced activity with the cytostatic drug 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU) and structurally related alkylating agents was obtained by molecular evolution. Mutant libraries created by recursive recombination of cDNA coding for human and rodent Theta-class GSTs were heterologously expressed in Escherichia coli and screened with the surrogate substrate 4-nitrophenethyl bromide (NPB) for enhanced alkyltransferase activity. A mutant with a 70-fold increased catalytic efficiency with NPB, compared to human GST T1-1, was isolated. The efficiency in degrading BCNU had improved 170-fold, significantly more than with the model substrate NPB. The enhanced catalytic activity of the mutant GST was also 2-fold higher with BCNU than wild-type mouse GST T1-1, which is 80-fold more efficient than wild-type human GST T1-1. We propose that GSTs catalyzing inactivation of anticancer drugs may find clinical use in protecting sensitive normal tissues to toxic side-effects in treated patients, and as selectable markers in gene therapy. Copyright 2010 Elsevier Inc. All rights reserved.

  18. Glutathione transferase (GST) as a candidate molecular-based biomarker for soil toxin exposure in the earthworm Lumbricus rubellus

    International Nuclear Information System (INIS)

    LaCourse, E. James; Hernandez-Viadel, Mariluz; Jefferies, James R.; Svendsen, Claus; Spurgeon, David J.; Barrett, John; John Morgan, A.; Kille, Peter; Brophy, Peter M.

    2009-01-01

    The earthworm Lumbricus rubellus (Hoffmeister, 1843) is a terrestrial pollution sentinel. Enzyme activity and transcription of phase II detoxification superfamily glutathione transferases (GST) is known to respond in earthworms after soil toxin exposure, suggesting GST as a candidate molecular-based pollution biomarker. This study combined sub-proteomics, bioinformatics and biochemical assay to characterise the L. rubellus GST complement as pre-requisite to initialise assessment of the applicability of GST as a biomarker. L. rubellus possesses a range of GSTs related to known classes, with evidence of tissue-specific synthesis. Two affinity-purified GSTs dominating GST protein synthesis (Sigma and Pi class) were cloned, expressed and characterised for enzyme activity with various substrates. Electrospray ionisation mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) following SDS-PAGE were superior in retaining subunit stability relative to two-dimensional gel electrophoresis (2-DE). This study provides greater understanding of Phase II detoxification GST superfamily status of an important environmental pollution sentinel organism. - This study currently provides the most comprehensive view of the Phase II detoxification enzyme superfamily of glutathione transferases within the important environmental pollution sentinel earthworm Lumbricus rubellus.

  19. Effects of cerium dioxide nanoparticles in Oncorhynchus mykiss liver after an acute exposure: assessment of oxidative stress, genotoxicity and histological alterations

    Directory of Open Access Journals (Sweden)

    Ana Cristina Nunes

    2015-12-01

    Full Text Available At present cerium oxide nanoparticles (CeO2 NP have numerous applications ranging from industry to the household, leading to its wide distribution namely in the aquatic environment. The hereby study aimed to assess the toxic effects of CeO2 NPs in Oncorhynchus mykiss liver following an acute exposure (96h to three different concentrations (0.25, 2.5 and 25 mg/L in terms of the genotoxicity (comet assay, oxidative stress response (Catalase CAT; Glutathione S-Transferases GSTs; Thiobarbituric Acid Reactive Substances TBARS and histopathology. CeO2 NP exposure resulted in genotoxic damage in all exposure treatments, inhibition of CAT in the highest concentration and histopathological changes in all exposure concentrations with predominance of progressive and circulatory alterations. However TBARS and GSTs showed no significant differences comparatively to the control (unexposed group. The results suggest that CeO2 NP are able to cause genotoxicity, biochemical impairment and histological alterations in the liver of rainbow trout.

  20. Novel function of N,N-bis(2-chloroethyl)docos-13-enamide for reversal of multidrug resistance in tongue cancer.

    Science.gov (United States)

    Qin, Qing; Ma, Peng-Fei; Kuang, Xiao-Cong; Gao, Ming-Xing; Mo, De-Huan; Xia, Shuang; Jin, Ning; Xia, Jun-Jie; Qi, Zhong-Quan; Lin, Cui-Wu

    2013-12-05

    Multidrug resistance (MDR) is a key element in the failure of chemotherapies, and development of agents to overcome MDR is crucial to improving cancer treatments. The overexpression of glutathione-S-transferases (GSTs) is one of the major mechanisms of MDR. Because some agents used in traditional Chinese medicine have strong antitumor effects coupled with low toxicity; we investigated the ability of N,N-bis(2-chloroethyl)docos-13-enamide (compound J), the synthesized analog of a highly unsaturated fatty acid from Isatis tinctoria L., to reverse the MDR induced by adriamycin (ADM) in TCA8113/ADM cells. We found that compound J significantly increased the cytotoxicity of ADM in TCA8113/ADM cells, with a reversal fold of 2.461. Analysis of the mechanisms through which compound J reversed MDR indicated that compound J significantly decreased the activity of GSTs and enhanced the depletion of GSH in TCA8113/ADM cells, but did not affect the P-glycoprotein (P-gp) efflux. Taken together, our data suggested that compound J was an excellent candidate for reversing MDR in cancer therapy. © 2013 Published by Elsevier B.V.