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Sample records for asparaginase

  1. Asparaginase Erwinia chrysanthemi

    Science.gov (United States)

    Asparaginase Erwinia chrysanthemi is used with other chemotherapy medications to treat acute lymphocytic leukemia (ALL; a type of cancer ... of allergic reactions to medications similar to asparaginase Erwinia chrysanthemi such as (asparaginase [Elspar] or pegaspargase [Oncaspar]). ...

  2. L-asparaginase treatment in acute lymphoblastic leukemia: a focus on Erwinia asparaginase

    Science.gov (United States)

    Pieters, Rob; Hunger, Stephen P; Boos, Joachim; Rizzari, Carmelo; Silverman, Lewis; Baruchel, Andre; Goekbuget, Nicola; Schrappe, Martin; Pui, Ching-Hon

    2010-01-01

    Asparaginases are a cornerstone of treatment protocols for acute lymphoblastic leukemia (ALL) and are used for remission induction and intensification treatment in all pediatric regimens and in the majority of adult protocols. Extensive clinical data have shown that intensive asparaginase treatment improves clinical outcomes in childhood ALL. Three asparaginase preparations are available; the native asparaginase derived from Escherichia coli (E. coli-asparaginase), a pegylated form of this enzyme (PEG-asparaginase) and a product isolated from Erwinia chrysanthemi, i.e. Erwinia asparaginase. Clinical hypersensitivity reactions and silent inactivation due to antibodies against E.coli-asparaginase, lead to inactivation of E-Coli asparaginase in up to 60% of cases. Current treatment protocols include E. coli-asparaginase or PEG-asparaginase for first-line treatment of ALL. Typically, patients exhibiting sensitivity to one formulation of asparaginase are switched to another product to ensure they receive the most efficacious treatment regimen possible. Erwinia asparaginase is used as a second- or third-line treatment in European and US protocols. Despite the universal inclusion of asparaginase in such treatment protocols, there is much debate regarding the optimal formulation and dosage of these agents. This manuscript provides an overview of available evidence to make recommendations for optimal use of Erwinia asparaginase in the treatment of ALL. PMID:20824725

  3. L-asparaginase treatment in acute lymphoblastic leukemia: a focus on Erwinia asparaginase.

    Science.gov (United States)

    Pieters, Rob; Hunger, Stephen P; Boos, Joachim; Rizzari, Carmelo; Silverman, Lewis; Baruchel, Andre; Goekbuget, Nicola; Schrappe, Martin; Pui, Ching-Hon

    2011-01-15

    Asparaginases are a cornerstone of treatment protocols for acute lymphoblastic leukemia (ALL) and are used for remission induction and intensification treatment in all pediatric regimens and in the majority of adult treatment protocols. Extensive clinical data have shown that intensive asparaginase treatment improves clinical outcomes in childhood ALL. Three asparaginase preparations are available: the native asparaginase derived from Escherichia coli (E. coli asparaginase), a pegylated form of this enzyme (PEG-asparaginase), and a product isolated from Erwinia chrysanthemi, ie, Erwinia asparaginase. Clinical hypersensitivity reactions and silent inactivation due to antibodies against E. coli asparaginase, lead to inactivation of E. coli asparaginase in up to 60% of cases. Current treatment protocols include E. coli asparaginase or PEG-asparaginase for first-line treatment of ALL. Typically, patients exhibiting sensitivity to one formulation of asparaginase are switched to another to ensure they receive the most efficacious treatment regimen possible. Erwinia asparaginase is used as a second- or third-line treatment in European and US protocols. Despite the universal inclusion of asparaginase in such treatment protocols, debate on the optimal formulation and dosage of these agents continues. This article provides an overview of available evidence for optimal use of Erwinia asparaginase in the treatment of ALL.

  4. Asparaginase-associated pancreatitis

    DEFF Research Database (Denmark)

    Wolthers, B O; Frandsen, T L; Abrahamsson, J;

    2016-01-01

    Asparaginase (ASP)-associated pancreatitis (AAP) occurs during acute lymphoblastic leukemia treatment. Among 1285 children (1.0-17.9 years) diagnosed during July 2008-December 2014 and treated according to the Nordic/Baltic ALL2008 protocol, 86 (cumulative incidence=6.8%) developed AAP. Seventy...... therapy, and 7% had recurrent abdominal pain. Germline DNA on 62 cases and 638 controls was genotyped on Omni2.5exome-8-v1.2 BeadChip arrays. Overall, the ULK2 variant rs281366 showed the strongest association with AAP (P=5.8 × 10(-7); odds ratio (OR)=6.7). Cases with the rs281366 variant were younger (4.......3 vs 8 years; P=0.015) and had lower risk of AAP-related complications (15% vs 43%; P=0.13) compared with cases without this variant. Among 45 cases and 517 controls associations with AAP were found for RGS6 variant rs17179470 (P=9.8 × 10(-9); OR=7.3). Rs281366 is located...

  5. Asparaginase-associated pancreatitis in children

    DEFF Research Database (Denmark)

    Raja, Raheel Altaf; Schmiegelow, Kjeld; Frandsen, Thomas Leth

    2012-01-01

    l-asparaginase has been an element in the treatment for acute lymphoblastic leukaemia (ALL) and non-Hodgkin lymphoma since the late 1960s and remains an essential component of their combination chemotherapy. Among the major toxicities associated with l-asparaginase therapy are pancreatitis......, allergic reactions, thrombotic events, hepatotoxicity and hyperlipidaemia. Acute pancreatitis is one of the most common reasons for stopping treatment with l-asparaginase. Short-term complications of asparaginase-associated pancreatitis include development of pseudocysts and pancreatic necrosis. Long......-term complications include chronic pancreatitis and diabetes. The pathophysiology of asparaginase-associated pancreatitis remains to be uncovered. Individual clinical and genetic risk factors have been identified, but they are only weak predictors of pancreatitis. This review explores the definition, possible risk...

  6. Optimizing asparaginase therapy for acute lymphoblastic leukemia.

    Science.gov (United States)

    Rizzari, Carmelo; Conter, Valentino; Starý, Jan; Colombini, Antonella; Moericke, Anja; Schrappe, Martin

    2013-03-01

    Asparaginases are important agents used in the treatment of children with acute lymphoblastic leukemia (ALL). Three types of asparaginase are currently available: two are derived from Escherichia coli [native asparaginase and pegylated asparaginase (PEG-asparaginase)] and one from Erwinia chrysanthemi (crisantaspase). All three products share the same mechanism of action but have different pharmacokinetic properties, which do not make them easily interchangeable. Among the known toxicities and side-effects, allergic reactions and silent inactivation represent the most important limitations to the prolonged use of any asparaginase product, with associated reduced therapeutic effects and poorer outcomes. Routine real time monitoring can help to identify patients with silent inactivation and facilitate a switch to a different product to ensure continued depletion of asparagine, completion of the treatment schedule and maintenance of outcomes. However, the most appropriate second-line treatment is still a matter of debate. PEG-asparaginase has lower immunogenicity and a longer half-life than native Escherichia coli (E. coli) asparaginase, which makes it useful for both first-line and second-line use with a reduced number of doses. However, PEG-asparaginase displays cross-reactivity with native E. coli asparaginase that may harm its therapeutic effects. Crisantaspase does not display cross-reactivity to either of the E. coli-derived products, which has made crisantaspase the second-line treatment option in a number of recent protocols. As crisantaspase has a much shorter biological half-life than the E. coli-derived products, the appropriate dosage and administration schedule are of paramount importance in delivering treatment with this product. In the ongoing trial AIEOP-BFM ALL 2009 (Associazione Italiana Ematologia Oncologia Pediatrica - Berlin-Franklin-Munster), in which PEG-asparaginase is used first-line, one dose of PEG-asparaginase is substituted by seven doses

  7. A prospective study on drug monitoring of PEGasparaginase and Erwinia asparaginase and asparaginase antibodies in pediatric acute lymphoblastic leukemia.

    Science.gov (United States)

    Tong, Wing H; Pieters, Rob; Kaspers, Gertjan J L; te Loo, D Maroeska W M; Bierings, Marc B; van den Bos, Cor; Kollen, Wouter J W; Hop, Wim C J; Lanvers-Kaminsky, Claudia; Relling, Mary V; Tissing, Wim J E; van der Sluis, Inge M

    2014-03-27

    This study prospectively analyzed the efficacy of very prolonged courses of pegylated Escherichia coli asparaginase (PEGasparaginase) and Erwinia asparaginase in pediatric acute lymphoblastic leukemia (ALL) patients. Patients received 15 PEGasparaginase infusions (2500 IU/m(2) every 2 weeks) in intensification after receiving native E coli asparaginase in induction. In case of allergy to or silent inactivation of PEGasparaginase, Erwinia asparaginase (20 000 IU/m(2) 2-3 times weekly) was given. Eighty-nine patients were enrolled in the PEGasparaginase study. Twenty (22%) of the PEGasparaginase-treated patients developed an allergy; 7 (8%) showed silent inactivation. The PEGasparaginase level was 0 in all allergic patients (grade 1-4). Patients without hypersensitivity to PEGasparaginase had serum mean trough levels of 899 U/L. Fifty-nine patients were included in the Erwinia asparaginase study; 2 (3%) developed an allergy and none silent inactivation. Ninety-six percent had at least 1 trough level ≥100 U/L. The serum asparagine level was not always completely depleted with Erwinia asparaginase in contrast to PEGasparaginase. The presence of asparaginase antibodies was related to allergies and silent inactivation, but with low specificity (64%). Use of native E coli asparaginase in induction leads to high hypersensitivity rates to PEGasparaginase in intensification. Therefore, PEGasparaginase should be used upfront in induction, and we suggest that the dose could be lowered. Switching to Erwinia asparaginase leads to effective asparaginase levels in most patients. Therapeutic drug monitoring has been added to our ALL-11 protocol to individualize asparaginase therapy.

  8. Nitrogen catabolite repression of asparaginase II in Saccharomyces cerevisiae.

    OpenAIRE

    Dunlop, P C; Meyer, G M; Roon, R J

    1980-01-01

    The biosynthesis of asparaginase II in Saccharomyces cerevisiae is subject to strong catabolite repression by a variety of nitrogen compounds. In the present study, asparaginase II synthesis was examined in a wild-type yeast strain and in strains carrying gdhA, gdhCR, or gdhCS mutations. The following effects were observed: (i) In the wild-type strain, the biosynthesis of asparaginase II was strongly repressed when either 10 mM ammonium sulfate or various amino acids (10 mM) served as the sou...

  9. Production of L-Asparaginase by the marine luminous bacteria

    Digital Repository Service at National Institute of Oceanography (India)

    Ramaiah, N.; Chandramohan, D.

    Fortythree strains of luminous bacteria, belonging to 4 species, (Vibrio harveyi, V. fischeri, Photobacterium leiognathi and P. phosphoreum) isolated from different marine samples, were examined for the production of L-asparaginase. Presence...

  10. Acrylamide diminishing in potato chips by using commercial Asparaginase

    DEFF Research Database (Denmark)

    Pedreschi, Franco; Mariotti, Salomé; Granby, Kit

    2011-01-01

    of potato chips. Control and asparaginase treated potato slices (Verdi variety, diameter: 40 mm, width: 2.0 mm) were fried at 170 °C for 5 min. Potato slices were treated in one of the following ways: (i) Rinsing in distilled water (control A); (ii) Blanching in hot water at 85 °C for 3.5 min (control B......); (iii) Immersing in a 10000 ASNU/l asparaginase solution at 40° C for 20 min; (iv) Immersing in a 10000 ASNU/l asparaginase solution at 50° C for 10 min; (v) Immersing in a 10000 ASNU/l asparaginase solution at 50° C for 20 min; (vi) Blanching in hot water at 85°C for 3.5 min plus immersing in a 10000...

  11. Asparaginase Potentiates Glucocorticoid-Induced Osteonecrosis in a Mouse Model.

    Science.gov (United States)

    Liu, Chengcheng; Janke, Laura J; Kawedia, Jitesh D; Ramsey, Laura B; Cai, Xiangjun; Mattano, Leonard A; Boyd, Kelli L; Funk, Amy J; Relling, Mary V

    2016-01-01

    Osteonecrosis is a common dose-limiting toxicity of glucocorticoids. Data from clinical trials suggest that other medications can increase the risk of glucocorticoid-induced osteonecrosis. Here we utilized a mouse model to study the effect of asparaginase treatment on dexamethasone-induced osteonecrosis. Mice receiving asparaginase along with dexamethasone had a higher rate of osteonecrosis than those receiving only dexamethasone after 6 weeks of treatment (44% vs. 10%, P = 0.006). Similarly, epiphyseal arteriopathy, which we have shown to be an initiating event for osteonecrosis, was observed in 58% of mice receiving asparaginase and dexamethasone compared to 17% of mice receiving dexamethasone only (P = 0.007). As in the clinic, greater exposure to asparaginase was associated with greater plasma exposure to dexamethasone (P = 0.0001). This model also recapitulated other clinical risk factors for osteonecrosis, including age at start of treatment, and association with the systemic exposure to dexamethasone (P = 0.027) and asparaginase (P = 0.036). We conclude that asparaginase can potentiate the osteonecrotic effect of glucocorticoids.

  12. Marine Microorganism: An Underexplored Source of l-Asparaginase.

    Science.gov (United States)

    Prihanto, A A; Wakayama, M

    2016-01-01

    l-Asparaginase (EC 3.5.1.1) is an enzyme that catalyzes the hydrolysis of l-asparagine to l-aspartic acid. This enzyme has an important role in medicine and food. l-Asparaginase is a potential drug in cancer therapy. Furthermore, it is also applied for reducing acrylamide, a carcinogenic compound in baked and fried foods. Until now, approved l-asparaginases for both applications are few due to their lack of appropriate properties. As a result, researchers have been enthusiastically seeking new sources of enzyme with better performance. A great number of terrestrial l-asparaginase-producing microorganisms have been reported but unfortunately, almost all failed to meet criteria for cancer therapy and acrylamide reducing agent. As a largest area than Earth, marine environment, by contrast, has not been optimally explored yet. So far, a great challenge facing an exploration of marine microorganisms is mainly due to their harsh, mysterious, and dangerous environment. It is clear that marine environment, a gigantic potential source for marine natural products is scantily revealed, although several approaches and technologies have been developed. This chapter presents the historical of l-asparaginase discovery and applications. It is also discussed, how the marine environment, even though offering a great potency but is still one of the less explored area for l-asparaginase-producing microorganisms.

  13. Isolation and screening of L-asparaginase free of glutaminase and urease from fungal sp.

    Science.gov (United States)

    Doriya, Kruthi; Kumar, Devarai Santhosh

    2016-12-01

    L-Asparaginase is a chemotherapeutic drug used in the treatment of acute lymphoblastic leukaemia (ALL), a malignant disorder in children. L-Asparaginase helps in removing acrylamide found in fried and baked foods that is carcinogenic in nature. L-Asparaginase is present in plants, animals and microbes. Various microorganisms such as bacteria, yeast and fungi are generally used for the production of L-asparaginase as it is difficult to obtain the same from plants and animals. L-Asparaginase from bacteria causes anaphylaxis and other abnormal sensitive reactions due to low specificity to asparagine. Toxicity and repression caused by bacterial L-asparaginase shifted focus to eukaryotic microorganisms such as fungi to improve the efficacy of L-asparaginase. Clinically available L-asparaginase has glutaminase and urease that may lead to side effects during treatment of ALL. Current work tested 45 fungal strains isolated from soil and agricultural residues. Isolated fungi were tested using conventional plate assay method with two indicator dyes, phenol red and bromothymol blue (BTB), and results were compared. L-Asparaginase activity was measured by cultivating in modified Czapek-Dox medium. Four strains have shown positive result for L-asparaginase production with no urease or glutaminase activity, among these C7 has high enzyme index of 1.57 and L-asparaginase activity of 33.59 U/mL. L-Asparaginase production by C7 was higher with glucose as carbon source and asparagine as nitrogen source. This is the first report focussing on fungi that can synthesize L-asparaginase of the desired specificity. Since the clinical toxicity of L-asparaginase is attributed to glutaminase and urease activity, available evidence indicates variants negative for glutaminase and urease would provide higher therapeutic index than variants positive for glutaminase and urease.

  14. Expression, purification and crystallization of Helicobacter pyloril-asparaginase

    Energy Technology Data Exchange (ETDEWEB)

    Dhavala, Prathusha [Turku Centre for Biotechnology, University of Turku and Åbo Akademi, Turku 20521 (Finland); Krasotkina, Julya [Institute for Biomedical Sciences, Russian Academy of Medical Sciences, Moscow (Russian Federation); Dubreuil, Christine; Papageorgiou, Anastassios C., E-mail: tassos.papageorgiou@btk.fi [Turku Centre for Biotechnology, University of Turku and Åbo Akademi, Turku 20521 (Finland)

    2008-08-01

    l-Asparaginase from H. pylori was overexpressed in E. coli, purified and crystallized. The crystals belonged to space group I222, with unit-cell parameters a = 63.6, b = 94.9, c = 100.2 Å and one molecule in the asymmetric unit. A complete data set to 1.6 Å resolution was collected using synchrotron radiation. The l-asparaginases from Escherichia coli and Erwinia chrysanthemi are effective drugs that have been used in the treatment of acute childhood lymphoblastic leukaemia for over 30 years. However, despite their therapeutic potential, they can cause serious side effects as a consequence of their intrinsic glutaminase activity, which leads to l-glutamine depletion in the blood. Consequently, new asparaginases with low glutaminase activity, fewer side effects and high activity towards l-asparagine are highly desirable as better alternatives in cancer therapy. l-Asparaginase from Helicobacter pylori was overexpressed in E. coli and purified for structural studies. The enzyme was crystallized at pH 7.0 in the presence of 16–19%(w/v) PEG 4000 and 0.1 M magnesium formate. Data were collected to 1.6 Å resolution at 100 K from a single crystal at a synchrotron-radiation source. The crystals belong to space group I222, with unit-cell parameters a = 63.6, b = 94.9, c = 100.2 Å and one molecule of l-asparaginase in the asymmetric unit. Elucidation of the crystal structure will provide insight into the active site of the enzyme and a better understanding of the structure–activity relationship in l-asparaginases.

  15. Cell-Cycle Inhibition by Helicobacter pylori L-Asparaginase

    Science.gov (United States)

    Scotti, Claudia; Sommi, Patrizia; Pasquetto, Maria Valentina; Cappelletti, Donata; Stivala, Simona; Mignosi, Paola; Savio, Monica; Chiarelli, Laurent Roberto; Valentini, Giovanna; Bolanos-Garcia, Victor M.; Merrell, Douglas Scott; Franchini, Silvia; Verona, Maria Luisa; Bolis, Cristina; Solcia, Enrico; Manca, Rachele; Franciotta, Diego; Casasco, Andrea; Filipazzi, Paola; Zardini, Elisabetta; Vannini, Vanio

    2010-01-01

    Helicobacter pylori (H. pylori) is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application. PMID:21085483

  16. L-asparaginase treatment in acute lymphoblastic leukemia

    NARCIS (Netherlands)

    R. Pieters (Rob); S.P. Hunger (Stephen); J. Boos (Joachim); C. Rizzari (Carmelo); L.B. Silverman (Lewis); A. Baruchel (André); N. Goekbuget (Nicola); M. Schrappe (Martin); C.H. Pui (Ching-Hon)

    2011-01-01

    textabstractAsparaginases are a cornerstone of treatment protocols for acute lymphoblastic leukemia (ALL) and are used for remission induction and intensification treatment in all pediatric regimens and in the majority of adult treatment protocols. Extensive clinical data have shown that intensive a

  17. Cell-cycle inhibition by Helicobacter pylori L-asparaginase.

    Directory of Open Access Journals (Sweden)

    Claudia Scotti

    Full Text Available Helicobacter pylori (H. pylori is a major human pathogen causing chronic gastritis, peptic ulcer, gastric cancer, and mucosa-associated lymphoid tissue lymphoma. One of the mechanisms whereby it induces damage depends on its interference with proliferation of host tissues. We here describe the discovery of a novel bacterial factor able to inhibit the cell-cycle of exposed cells, both of gastric and non-gastric origin. An integrated approach was adopted to isolate and characterise the molecule from the bacterial culture filtrate produced in a protein-free medium: size-exclusion chromatography, non-reducing gel electrophoresis, mass spectrometry, mutant analysis, recombinant protein expression and enzymatic assays. L-asparaginase was identified as the factor responsible for cell-cycle inhibition of fibroblasts and gastric cell lines. Its effect on cell-cycle was confirmed by inhibitors, a knockout strain and the action of recombinant L-asparaginase on cell lines. Interference with cell-cycle in vitro depended on cell genotype and was related to the expression levels of the concurrent enzyme asparagine synthetase. Bacterial subcellular distribution of L-asparaginase was also analysed along with its immunogenicity. H. pylori L-asparaginase is a novel antigen that functions as a cell-cycle inhibitor of fibroblasts and gastric cell lines. We give evidence supporting a role in the pathogenesis of H. pylori-related diseases and discuss its potential diagnostic application.

  18. A Study on L-Asparaginase of Nocardia levis MK-VL_113

    Directory of Open Access Journals (Sweden)

    Alapati Kavitha

    2012-01-01

    Full Text Available An enzyme-based drug, L-asparaginase, was produced by Nocardia levis MK-VL_113 isolated from laterite soils of Guntur region. Cultural parameters affecting the production of L-asparaginase by the strain were optimized. Maximal yields of L-asparaginase were recorded from 3-day-old culture grown in modified asparagine-glycerol salts broth with initial pH 7.0 at temperature 30∘C. Glycerol (2% and yeast extract (1.5% served as good carbon and nitrogen sources for L-asparaginase production, respectively. Cell-disrupting agents like EDTA slightly enhanced the productivity of L-asparaginase. Ours is the first paper on the production of L-asparaginase by N. levis.

  19. Role of L-asparaginase in acute lymphoblastic leukemia: focus on adult patients

    Directory of Open Access Journals (Sweden)

    Rytting ME

    2012-06-01

    Full Text Available Michael E RyttingDepartment of Pediatrics and Leukemia, University of Texas MD Anderson Cancer Center, Houston, TX, USAAbstract: Asparaginase preparations deplete asparagine in acute lymphoblastic leukemia (ALL blasts. Asparaginase in its various forms is an important component of treatment regimens for pediatric ALL. Recently, interest and use of asparaginase in adult patients with ALL has increased, particularly in young adults. There is much less information on asparaginase use and toxicity in adult compared with pediatric populations. This review surveys prior published studies of the three most commonly used asparagine preparations as used in adult patients, and discusses important toxicities encountered in adult patients who receive asparaginase preparations.Keywords: asparaginase, leukemia, adults, children

  20. PEG-asparaginase allergy in children with acute lymphoblastic leukemia in the NOPHO ALL2008 protocol

    DEFF Research Database (Denmark)

    Henriksen, Louise Tram; Harila-Saari, Arja; Ruud, Ellen;

    2015-01-01

    BACKGROUND: L-Asparaginase is an effective drug in the treatment of childhood acute lymphoblastic leukemia (ALL). The use of L-asparaginase may be limited by serious adverse events of which allergy is the most frequent. The objective of this study was to describe the clinical aspects of PEG......-asparaginase allergy in children treated according to the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol. PROCEDURE: Children (1-17 years) enrolled in the NOPHO ALL2008 protocol between July 2008 and August 2011, who developed PEG-asparaginase allergy were identified through the NOPHO...

  1. Metabolism of proteins and glycoproteins in tumour bearing mice treated with Aeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Muraleedhara, K G; Sreejith, K; Jayashree, G

    1996-12-01

    L-asparaginase, isolated in our laboratory, from Aeromonas had been found to be antileukaemic. In the present study, changes in the levels of proteins and glycoproteins in leukaemic mice and under treatment with Aeromonas L-asparaginase have been compared. Levels of protein bound hexose, fucose and sialic acid which were increased during leukaemia attained normal levels when treated with L-asparaginase. The increased blood urea level declined significantly during enzyme therapy. Effects of L-asparaginase are compared with 'Leunase', a commercially available drug used in the treatment of leukaemia.

  2. Neurosurgical management of L-asparaginase induced haemorrhagic stroke.

    LENUS (Irish Health Repository)

    Ogbodo, Elisha

    2012-01-01

    The authors describe a case of L-asparaginase induced intracranial thrombosis and subsequent haemorrhage in a newly diagnosed 30-year-old man with acute lymphoblastic leukaemia who was successfully managed by surgical intervention. At presentation, he had a Glasgow Coma Score of 7\\/15, was aphasic and had dense right hemiplegia. Neuroimaging revealed an acute anterior left middle cerebral artery infarct with parenchymal haemorrhagic conversion, mass effect and subfalcine herniation. He subsequently underwent left frontal craniotomy and evacuation of large frontal haematoma and decompressive craniectomy for cerebral oedema. Six months postoperatively he underwent titanium cranioplasty. He had made good clinical recovery and is currently mobilising independently with mild occasional episodes of expressive dysphasia, difficulty with fine motor movement on the right side, and has remained seizure free. This is the first documented case of L-asparaginase induced haemorrhagic stroke managed by neurosurgical intervention. The authors emphasise the possible role of surgery in managing chemotherapy induced intracranial complications.

  3. Solid-State Fermentation vs Submerged Fermentation for the Production of l-Asparaginase.

    Science.gov (United States)

    Doriya, K; Jose, N; Gowda, M; Kumar, D S

    l-Asparaginase, an enzyme that catalyzes l-asparagine into aspartic acid and ammonia, has relevant applications in the pharmaceutical and food industry. So, this enzyme is used in the treatment of acute lymphoblastic leukemia, a malignant disorder in children. This enzyme is also able to reduce the amount of acrylamide found in carbohydrate-rich fried and baked foods which is carcinogenic to humans. The concentration of acrylamide in food can be reduced by deamination of asparagine using l-Asparaginase. l-Asparaginase is present in plants, animals, and microbes. Various microorganisms such as bacteria, yeast, and fungi are generally used for the production of l-Asparaginase as it is difficult to obtain the same from plants and animals. l-Asparaginase from bacteria causes anaphylaxis and other abnormal sensitive reactions. To overcome this, eukaryotic organisms such as fungi can be used for the production of l-Asparaginase. l-Asparaginase can be produced either by solid-state fermentation (SSF) or by submerged fermentation (SmF). SSF is preferred over SmF as it is cost effective, eco-friendly and it delivers high yield of enzyme. SSF process utilizes agricultural and industrial wastes as solid substrate. The contamination level is substantially reduced in SSF through low moisture content. Current chapter will discuss in detail the chemistry and applications of l-Asparaginase enzyme and various methods available for the production of the enzyme, especially focusing on the advantages and limitations of SSF and SmF processes.

  4. Withania somnifera (Ashwagandha): a Novel Source of L-asparaginase

    Institute of Scientific and Technical Information of China (English)

    Vishal P. Oza; Shraddha D.Trivedi; Pritesh P.Parmar; R.B.Subramanian

    2009-01-01

    Different parts of plant species belonging to Solanaceae and Fabaceae families were screened for L-asparaginase enzyme (E.C.3.5.1.1.). Among 34 plant species screened for L-asparaginase enzyme, Withania somnifera L. Was identified as a potential source of the enzyme on the basis of high specific activity of the enzyme. The enzyme was purified and characterized from W. Somnifera, a popular medicinal plant in South East Asia and Southern Europe. Purification was carried out by a combination of protein precipitation with ammonium sulfate as well as Sephadex-gel filtration. The purified enzyme is a homodimer, with a molecular mass of 72±0.5 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresisand size exclusion chromatography. The enzyme has a pH optimum of 8.5 and an optimum temperature of 37℃. The Km value for the enzyme is 6.1×10-2 mmol/L. This is the first report for L-asparaginase from W. Somnifera, a traditionally used Indian medicinal plant.

  5. Tackling Critical Catalytic Residues in Helicobacter pylori L-Asparaginase

    Directory of Open Access Journals (Sweden)

    Maristella Maggi

    2015-03-01

    Full Text Available Bacterial asparaginases (amidohydrolases, EC 3.5.1.1 are important enzymes in cancer therapy, especially for Acute Lymphoblastic Leukemia. They are tetrameric enzymes able to catalyze the deamination of L-ASN and, to a variable extent, of L-GLN, on which leukemia cells are dependent for survival. In contrast to other known L-asparaginases, Helicobacter pylori CCUG 17874 type II enzyme (HpASNase is cooperative and has a low affinity towards L-GLN. In this study, some critical amino acids forming the active site of HpASNase (T16, T95 and E289 have been tackled by rational engineering in the attempt to better define their role in catalysis and to achieve a deeper understanding of the peculiar cooperative behavior of this enzyme. Mutations T16E, T95D and T95H led to a complete loss of enzymatic activity. Mutation E289A dramatically reduced the catalytic activity of the enzyme, but increased its thermostability. Interestingly, E289 belongs to a loop that is very variable in L-asparaginases from the structure, sequence and length point of view, and which could be a main determinant of their different catalytic features.

  6. Asparaginase Erwinia chrysanthemi (Erwinaze®): a guide to its use in acute lymphoblastic leukemia in the USA.

    Science.gov (United States)

    Keating, Gillian M

    2013-08-01

    Asparaginase Erwinia chrysanthemi (Erwinaze®) is approved in the USA for use in patients with acute lymphoblastic leukemia (ALL) who have developed hypersensitivity to Escherichia coli-derived asparaginase. The approved regimen of intramuscular Erwinaze® was associated with sustained, clinically meaningful asparaginase activity in patients with ALL who had to discontinue treatment with pegaspargase (a pegylated formulation of E. coli asparaginase) because of hypersensitivity. Another study revealed that development of E. coli-derived asparaginase allergy and a switch to Erwinaze® maintained event-free survival in pediatric patients with newly diagnosed ALL. In a multicenter, compassionate-use trial, Erwinaze® was generally well tolerated, with the most commonly occurring adverse events including hypersensitivity, pancreatitis, fever, hyperglycemia, and increased transaminase levels. Subclinical hypersensitivity may result in the inactivation of asparaginase and affect treatment outcome; monitoring of serum asparaginase levels may be used to identify subclinical hypersensitivity.

  7. A critical review on properties and applications of microbial l-asparaginases.

    Science.gov (United States)

    Krishnapura, Prajna Rao; Belur, Prasanna D; Subramanya, Sandeep

    2016-09-01

    l-Asparaginase is one of the main drugs used in the treatment of acute lymphoblastic leukemia (ALL), a commonly diagnosed pediatric cancer. Although several microorganisms are found to produce l-asparaginase, only the purified enzymes from E. coli and Erwinia chrysanthemi are employed in the clinical and therapeutic applications in humans. However, their therapeutic response seldom occurs without some evidence of hypersensitivity and other toxic side effects. l-Asparaginase is also of prospective use in food industry to reduce the formation of acrylamide in fried, roasted or baked food products. This review is an attempt to compile information on the properties of l-asparaginases obtained from different microorganisms. The complications involved with the therapeutic use of the currently available l-asparaginases, and the enzyme's potential application as a food processing aid to mitigate acrylamide formation have also been reviewed. Further, avenues for searching alternate sources of l-asparaginase have been discussed, highlighting the prospects of endophytic microorganisms as a possible source of l-asparaginases with varied biochemical and pharmacological properties.

  8. Recent developments in L-asparaginase discovery and its potential as anticancer agent.

    Science.gov (United States)

    Shrivastava, Abhinav; Khan, Abdul Arif; Khurshid, Mohsin; Kalam, Mohd Abul; Jain, Sudhir K; Singhal, Pradeep K

    2016-04-01

    L-Asparaginase (EC3.5.1.1) is an enzyme, which is used for treatment of acute lymphoblastic leukaemia (ALL) and other related blood cancers from a long time. This enzyme selectively hydrolyzes the extracellular amino acid L-asparagine into L-aspartate and ammonia, leading to nutritional deficiencies, protein synthesis inhibition, and ultimately death of lymphoblastic cells by apoptosis. Currently, bacterial asparaginases are used for treatment purpose but offers scepticism due to a number of toxicities, including thrombosis, pancreatitis, hyperglycemia, and hepatotoxicity. Resistance towards bacterial asparaginase is another major disadvantage during cancer management. This situation attracted attention of researchers towards alternative sources of L-asparaginase, including plants and fungi. Present article discusses about potential of L-asparaginase as an anticancer agent, its mechanism of action, and adverse effects related to current asparaginase formulations. This article also provides an outlook for recent developments in L-asparaginase discovery from alternative sources and their potential as a less toxic alternative to current formulations.

  9. Endophytic l-asparaginase-producing fungi from plants associated with anticancer properties.

    Science.gov (United States)

    Chow, YiingYng; Ting, Adeline S Y

    2015-11-01

    Endophytes are novel sources of natural bioactive compounds. This study seeks endophytes that produce the anticancer enzyme l-asparaginase, to harness their potential for mass production. Four plants with anticancer properties; Cymbopogon citratus, Murraya koenigii, Oldenlandia diffusa and Pereskia bleo, were selected as host plants. l-Asparaginase-producing endophytes were detected by the formation of pink zones on agar, a result of hydrolyzes of asparagine into aspartic acid and ammonia that converts the phenol red dye indicator from yellow (acidic condition) to pink (alkaline condition). The anticancer enzyme asparaginase was further quantified via Nesslerization. Results revealed that a total of 89 morphotypes were isolated; mostly from P. bleo (40), followed by O. diffusa (25), C. citratus (14) and M. koenigii (10). Only 25 of these morphotypes produced l-asparaginase, mostly from P. bleo and their asparaginase activities were between 0.0069 and 0.025 μM mL(-1) min(-1). l-Asparaginase producing isolates were identified as probable species of the genus Colletotrichum, Fusarium, Phoma and Penicillium. Studies here revealed that endophytes are good alternative sources for l-asparaginase production and they can be sourced from anticancer plants, particularly P. bleo.

  10. Endophytic l-asparaginase-producing fungi from plants associated with anticancer properties

    Directory of Open Access Journals (Sweden)

    YiingYng Chow

    2015-11-01

    Full Text Available Endophytes are novel sources of natural bioactive compounds. This study seeks endophytes that produce the anticancer enzyme l-asparaginase, to harness their potential for mass production. Four plants with anticancer properties; Cymbopogon citratus, Murraya koenigii, Oldenlandia diffusa and Pereskia bleo, were selected as host plants. l-Asparaginase-producing endophytes were detected by the formation of pink zones on agar, a result of hydrolyzes of asparagine into aspartic acid and ammonia that converts the phenol red dye indicator from yellow (acidic condition to pink (alkaline condition. The anticancer enzyme asparaginase was further quantified via Nesslerization. Results revealed that a total of 89 morphotypes were isolated; mostly from P. bleo (40, followed by O. diffusa (25, C. citratus (14 and M. koenigii (10. Only 25 of these morphotypes produced l-asparaginase, mostly from P. bleo and their asparaginase activities were between 0.0069 and 0.025 μM mL−1 min−1. l-Asparaginase producing isolates were identified as probable species of the genus Colletotrichum, Fusarium, Phoma and Penicillium. Studies here revealed that endophytes are good alternative sources for l-asparaginase production and they can be sourced from anticancer plants, particularly P. bleo.

  11. Studies on optimization of growth parameters for L-asparaginase production by Streptomyces ginsengisoli.

    Science.gov (United States)

    Deshpande, Neelima; Choubey, Prachi; Agashe, Manasi

    2014-01-01

    A species of Streptomyces, Streptomyces ginsengisoli, a river isolate, was evaluated for production of an enzyme, L-asparaginase, with multiple functions mainly anticancer activity. The actinomycete was subjected to submerged fermentation by "shake flask" method. The quantity of L-asparaginase produced was estimated as 3.23 μ mol/mL/min. The effect of various culture conditions on L-asparaginase production was studied by adopting a method of variation in one factor at a time. Of the various conditions tested, glucose (followed by starch) and peptone served as good carbon and nitrogen sources, respectively, for maximal production of enzyme at pH 8. The temperature of 30 °C and an incubation period of 5 days with 0.05 g% asparagine concentration were found to be optimum for L-asparaginase production.

  12. Studies on Optimization of Growth Parameters for L-Asparaginase Production by Streptomyces ginsengisoli

    Directory of Open Access Journals (Sweden)

    Neelima Deshpande

    2014-01-01

    Full Text Available A species of Streptomyces, Streptomyces ginsengisoli, a river isolate, was evaluated for production of an enzyme, L-asparaginase, with multiple functions mainly anticancer activity. The actinomycete was subjected to submerged fermentation by “shake flask” method. The quantity of L-asparaginase produced was estimated as 3.23 μmol/mL/min. The effect of various culture conditions on L-asparaginase production was studied by adopting a method of variation in one factor at a time. Of the various conditions tested, glucose (followed by starch and peptone served as good carbon and nitrogen sources, respectively, for maximal production of enzyme at pH 8. The temperature of 30°C and an incubation period of 5 days with 0.05 g% asparagine concentration were found to be optimum for L-asparaginase production.

  13. Purification, characterization and antiproliferative activity of l-asparaginase from Aspergillus oryzae CCT 3940 with no glutaminase activity

    Directory of Open Access Journals (Sweden)

    Fernanda Furlan Gonçalves Dias

    2016-09-01

    Conclusions: The sensitivity of the cells lines to purified l-asparaginase from A. oryzae CCT 3940 appeared to be concentration dependent affording a more significant decrease in cell growth than that observed for the commercial l-asparaginase from Escherichia coli. The l-asparaginase from A. oryzae CCT 3940 has a high potential for pharmaceutical exploitation in the treatment of leukemia.

  14. Isolation and Identification of L-asparaginase producing Erwinia strains which isolated from Potato Farms

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    Arastoo Badoei-Dalfard

    2016-09-01

    Full Text Available Introduction: L-Asparaginase can be effectively used for the treatment of lymphoblastic leukemia. The rapid growth of cancer cells are needed for L-asparagine abundant storage. L-asparaginase catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. The purpose of this study was to isolate and identify the L-asparaginase producing Erwinia strains from the potato farms of Jiroft. Materials and methods: Pectolytic Erwinia species isolated from crumbling potato in M9 medium. The desired L-asparaginase producing bacteria were isolated based on the color changes. Biochemical-microbial and the plant pathogenicity tests of these strains were also investigated with potato and geranium. The L-asparaginase production and molecular detection of these Erwinia strains were also investigated. Results: In this study, L-asparaginase producing Erwinia was isolated on the CVP and M9 mediums. The inoculation of Erwinia strains on the potato and geranium plants showed that Er8 and Er11 species have the ability to cause plant pathogenicity. Results showed that the maximum pathogenicity of Er8 and Er11 was observed after 48 and 15 h of inoculation in potato and geranium plants, respectively. 16S rDNA sequencing and phylogenetic analyses exhibited that Er8 and Er11 strains were similar to Erwinia chrysanthemi with 98% homology. Discussion and conclusion: Because of several applications of the Erwinia L-asparaginase in various fields, isolated Erwinia and their L-asparaginase can be suitable for applied utilization.

  15. Production and optimization of L-asparaginase by an actinobacterium isolated from Nizampatnam mangrove ecosystem.

    Science.gov (United States)

    Kiranmayi, M Usha; Poda, Sudhakar; Vijayalakshmi, M

    2014-09-01

    The aim of the present study was to isolate and screen actinomycetes from the mangrove sediments of Nizampatnam that are potent to produce L-asparaginase, an enzyme that catalyses the hydrolysis of asparagine. A total of 31 actinomycetes strains were isolated, of which 6 strains were positive for L-asparaginase. Several physico-chemical parameters were optimized for maximizing L-asparaginase production by the potent strain identified as Pseudonocardia endophytica VUK-10. Production of L-asparaginase by the strain was high in modified Asparagine glucose salts broth (FM-4)(3.96 IU/ml) as compared to other tested media. Maltose(6.99 IU ml(-1)) and L-asparagine (7.42 IU ml(-1)) were found to be the most suitable carbon and nitrogen sources for optimum enzyme production. Maximum production of L-asparaginase was found in the culture medium with pH 8 and temperature 30 degrees C incubated for four days. This is the first report on the production of L-asparaginase by Pseudonocardia endophytica VUK-10 from Nizampatnam mangrove sediments.

  16. L-asparaginase production in the pseudomonas pseudoalcaligenes strain JHS-71 isolated from Jooshan Hot-spring

    Directory of Open Access Journals (Sweden)

    Arastoo Badoei-Dalfard

    2016-03-01

    Full Text Available L-asparaginase has lots of medical and industrial applications. Ever since L-asparaginase anti-tumor activity was first demonstrated, its production using microbial systems has attracted considerable attention owing to their cost-effective and eco-friendly nature. The aim of this study is to obtain L-asparaginase producing bacteria and determining the enzyme activity. Samples were picked up from Jooshan hot springs located in the Sirch, Kerman. The L-asparaginase producing bacteria were screened on the agar medium supplied with L-asparagine and phenol red indicator dye (pH-7.0. L-asparaginase activity was detected on the basis of pink color around the colony. Enzyme production was also performed based on ammonia detection by Nessler method. Among 24 strains, there were 7 strains which could produce L-asparaginase.Sequencing of 16S rRNA showed that, the best isolates producing L-asparaginase belongs to the Pseudomonas genus. Enzyme activity after 24 and 48 h of incubation showed that Pseudomonas pseudoalcaligenes strain JHS-71was the best strain that produced L-Asparaginase about 240 (U/ml after 48h of incubation. Results showed that, L-Asparaginase activity enhanced about 27% in the presence of Co+2. L-asparaginase JHS-71 retained more than 50% of its initial activity in the presence of Cu+2, Mn+2, Zn+2, Mg+2 and Fe+2. Because of various applications of L-asparaginase in biotechnology, P. pseudoalcaligenes strain JHS-71 can be used as a suitable candidate in these fields.

  17. Kinetic properties and inhibition of Acinetobacter glutaminase-asparaginase.

    Science.gov (United States)

    Steckel, J; Roberts, J; Philips, F S; Chou, T C

    1983-03-15

    Kinetic parameters, substrate specificity and exclusivity of ligands at binding sites of L-glutaminase-L-asparaginase purified from Acinetobacter glutaminasificans were studied in order to gain knowledge about the dual activities of this enzyme and its inhibition by structural analogs. Both L-glutamine and L-asparagine, which showed similar Km (4 approximately 7 X 10(-5) M) and Vmax (molecular activity 1.0 min-1) values, were competitive with each other for the substrate binding site. The products, L-glutamic acid and L-aspartic acid, showed competitive inhibition with respect to either L-glutamine or L-asparagine as substrates. Multiple inhibition of the glutaminase activity by L-glutamic acid and L-aspartic acid indicated that these ligands are mutually exclusive at the product-releasing site. The initial rates of both of the enzyme's activities were competitively inhibited by the following inhibitors (in rates of both of the enzyme's activities were competitively inhibited by the following inhibitors (in decreasing order of activity): 6-diazo-5-oxo-L-norleucine (DON), L-methionine sulfoximine, azaserine, and Acivicin. DON and azaserine inhibited both the asparaginase and glutaminase activities in a time-dependent and irreversible manner. The kinetic data suggest an ordered mechanism with glutamine or asparagine as the first substrate and glutamic acid or aspartic acid, respectively, as the last product. These results also suggest that a single mechanism and a single set of binding sites are responsible for catalyzing both of the enzyme's activities. The data also showed that succinylated enzyme, which has a 10-fold increase of plasma half-life in animals and humans and, thus, has benefit as a cancer chemotherapeutic agent, retained its catalytic activity and maintained Km and Vmax values similar to the native enzyme.

  18. Structural and kinetic characterization of guinea pig L-asparaginase type III.

    Science.gov (United States)

    Schalk, Amanda M; Lavie, Arnon

    2014-04-15

    We investigated whether an uncharacterized protein from guinea pig could be the enzyme behind Kidd's serendipitous discovery, made over 60 years ago, that guinea pig serum has cell killing ability. It has been long known that an enzyme with l-asparaginase activity is responsible for cell killing, although astonishingly, its identity remains unclear. Bacterial asparaginases with similar cell killing properties have since become a mainstay therapy of certain cancers such as acute lymphoblastic leukemia. By hydrolyzing asparagine to aspartate and ammonia, these drugs deplete the asparagine present in the blood, killing cancer cells that rely on extracellular asparagine uptake for survival. However, bacterial asparaginases can elicit an adverse immune response. We propose that replacement of bacterial enzymes with the guinea pig asparaginase responsible for serum activity, by its virtue of being more closely related to human enzymes, will be less immunogenic. To this goal, we investigated whether an uncharacterized protein from guinea pig with putative asparaginase activity, which we call gpASNase3, could be that enzyme. We examined its self-activation process (gpASNase3 requires autocleavage to become active), kinetically characterized it for asparaginase and β-aspartyl dipeptidase activity, and elucidated its crystal structure in both the uncleaved and cleaved states. This work reveals that gpASNase3 is not the enzyme responsible for the antitumor effects of guinea pig serum. It exhibits a low affinity for asparagine as measured by a high Michaelis constant, KM, in the millimolar range, in contrast to the low KM (micromolar range) required for asparaginase to be effective as an anticancer agent.

  19. L-asparaginase production by mangrove derived Bacillus cereus MAB5:optimization by response surface methodology

    Institute of Scientific and Technical Information of China (English)

    ThenmozhiC; SankarR; KaruppiahV; SampathkumarP

    2011-01-01

    Objective:To isolate marine bacteria, statistically optimize them for maximum asparaginase production. Methods:In the present study, statistically based experimental designs were applied to maximize the production of L-asparaginase from bacterial strain of Bacillus cereus (B. cereus) MAB5 (HQ675025) isolated and identified by 16S rDNA sequencing from mangroves rhizosphere sediment. Results:Plackett-Barman design was used to identify the interactive effect of the eight variables viz. yeast extract, soyabean meal, glucose, magnesium sulphate, KH2PO4, wood chips, aspargine and sodium chloride. All the variables are denoted as numerical factors and investigated at two widely spaced intervals designated as-1 (low level) and+1 (high level). The effect of individual parameters on L-asparaginase production was calculated. Soyabean meal, aspargine, wood chips and sodium chloride were found to be the significant among eight variables. The maximum amount of L-asparaginase produced (51.54 IU/mL) from the optimized medium containing soyabean meal (6.282 8 g/L), aspargine (5.5 g/L), wood chips (1.383 8 g/L) and NaCl (4.535 4 g/L). Conclusions:The study revealed that, it is useful to produce the maximum amount of L-asparaginase from B. cereus MAB5 for the treatment of various infections and diseases.

  20. Chemical modification of L-asparaginase from Cladosporium sp. for improved activity and thermal stability.

    Science.gov (United States)

    Mohan Kumar, N S; Kishore, Vijay; Manonmani, H K

    2014-01-01

    L-Asparaginase (ASNase), an antileukemia enzyme, is facing problems with antigenicity in the blood. Modification of L-asparaginase from Cladosporium sp. was tried to obtain improved stability and improved functionality. In our experiment, modification of the enzyme was tried with bovine serum albumin, ovalbumin by crosslinking using glutaraldehyde, N-bromosuccinimide, and mono-methoxy polyethylene glycol. Modified enzymes were studied for activity, temperature stability, rate constants (kd), and protection to proteolytic digestion. Modification with ovalbumin resulted in improved enzyme activity that was 10-fold higher compared to native enzyme, while modification with bovine serum albumin through glutaraldehyde cross-linking resulted in high stability of L-asparaginase that was 8.5- and 7.62-fold more compared to native enzyme at 28°C and 37°C by the end of 24 hr. These effects were dependent on the quantity of conjugate formed. Modification also markedly prolonged L-asparaginase half-life and serum stability. N-Bromosuccinimide-modified ASNase presented greater stability with prolonged in vitro half-life of 144 hr to proteolytic digestion relative to unmodified enzyme (93 h). The present work could be seen as producing a modified L-asparaginase with improved activity and stability and can be a potential source for developing therapeutic agents for cancer treatment.

  1. Biochemical characterization of recombinant L-asparaginase (AnsA) from Rhizobium etli, a member of an increasing rhizobial-type family of L-asparaginases.

    Science.gov (United States)

    Moreno-Enriquez, Angelica; Evangelista-Martinez, Zahaed; Gonzalez-Mondragon, Edith G; Calderon-Flores, Arturo; Arreguin, Roberto; Perez-Rueda, Ernesto; Huerta-Saquero, Alejandro

    2012-03-01

    We report the expression, purification, and characterization of L-asparaginase (AnsA) from Rhizobium etli. The enzyme was purified to homogeneity in a single-step procedure involving affinity chromatography, and the kinetic parameters K(m), V(max), and k(cat) for L-asparagine were determined. The enzymatic activity in the presence of a number of substrates and metal ions was investigated. The molecular mass of the enzyme was 47 kDa by SDS-PAGE. The enzyme showed a maximal activity at 50 degrees C, but the optimal temperature of activity was 37 degrees C. It also showed maximal and optimal activities at pH 9.0. The values of K(m), V(max), k(cat), and k(cat)/K(m) were 8.9 +/- 0.967 × 10⁻³ M, 128 +/- 2.8 U/mg protein, 106 +/- 2 s⁻¹, and 1.2 +/- 0.105 × 10⁴ M⁻¹s⁻¹, respectively. The L-asparaginase activity was reduced in the presence of Mn²⁺, Zn²⁺, Ca²⁺, and Mg²⁺ metal ions for about 52% to 31%. In addition, we found that NH₄⁺, L-Asp, D-Asn, and beta-aspartyl-hydroxamate in the reaction buffer reduced the activity of the enzyme, whereas L-Gln did not modify its enzymatic activity. This is the first report on the expression and characterization of the L-asparaginase (AnsA) from R. etli. Phylogenetic analysis of asparaginases reveals an increasing group of known sequences of the Rhizobialtype asparaginase II family.

  2. Serial Ultrasound Monitoring for Early Recognition of Asparaginase Associated Pancreatitis in Children With Acute Lymphoblastic Leukemia

    DEFF Research Database (Denmark)

    Raja, Raheel Altaf; Schmiegelow, K.; Henriksen, Birthe Merete;

    2015-01-01

    BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children and L-asparaginase is an essential component of the treatment. Cessation of L-asparaginase decreases event free survival. Acute pancreatitis is the toxicity that most commonly results in cessation of L...... protocol, with PEG-asparaginase of 2 or 6 week intervals, for 30 weeks had their pancreas monitored using serial ultrasound in order to detect early signs of inflammation. RESULTS: Nineteen of 31 eligible patients were included. Three of the included patients developed AAP. None of the patients, including...... the three patients that developed AAP, had signs of inflammatory edema or pancreas enzymes above three times the upper normal limit prior to AAP. CONCLUSION: We found no signs of inflammatory edema within the pancreas on ultrasound during treatment with PEG-asparginase in our cohort prior to development...

  3. Effect of Acinetobacter glutaminase-asparaginase treatment on free amino acids in mouse tissues.

    Science.gov (United States)

    Holcenberg, J S; Tang, E; Dolowy, W C

    1975-05-01

    Acinetobacter glutaminase-asparaginase (AGA) and Escherichia coli asparaginase were compared for their effects on plasma and tissue levels of amino acids, ammonia, and glutamyl transferase activity in the mouse. Free asparagine was depleted similarly in plasma and tissues by both enzymes. AGA treatment produced partial depletion of glutamine concentrations in muscle, spleen, small intestine, and liver. Brain and kidney glutamine concentrations actually rose with treatment. Despite over 100-fold increase in plasma glutamate, only the kidney showed a substantial increase in free glutamate levels during AGA treatment. Glutamine biosynthesis measured by glutamyl transferase activity showed an appreciable increase only in the kidney. Ammonia levels in tissues and plasma rose 1.3- to 4.3-fold. In general, E. coli asparaginase treatment had much less effect on these measurements than did AGA. The changes in these levels are discussed in relation to sites of possible toxicity and antitumor effects.

  4. Asparaginase II of Saccharomyces cerevisiae: selection of four mutations that cause derepressed enzyme synthesis.

    Science.gov (United States)

    Kamerud, J Q; Roon, R J

    1986-01-01

    A positive selection method was used to isolate four Saccharomyces cerevisiae mutations that cause derepressed synthesis of asparaginase II. The four mutations (and1, and2, and3, and4) were neither closely linked to each other nor linked to previously characterized mutations (asp3, asp6) which cause the complete loss of asparaginase II activity. One of the new mutations (and4) was shown to be allelic to gdh-CR, a pleiotropic mutation which causes derepressed synthesis of a number of enzymes of nitrogen catabolism.

  5. PRODUCTION OPTIMIZATION OF EXTRACELLULAR L-ASPARAGINASE THROUGH SOLID- STATE FERMENTATION BY ISOLATED BACILLUS SUBTILIS.

    Directory of Open Access Journals (Sweden)

    Susmita Shukla

    2013-02-01

    Full Text Available L-asparaginase has been used as anti-tumor agent for the treatment of acute lymphoblastic leukemia and food processing aid to reduce the formation of cancer causing acrylamide. Extracellular Lasparaginase production was optimized through solid state fermentation using ground nut cake by isolated Bacillus subtilis. which was not reported in literature.Optimum production of L-asparaginase enzyme (18.4U/ml was obtained after 48h of incubation at 370C moisture content of 70% and at pH 7.

  6. Levels of enzymes in leukaemic mice treated withAeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Muraleedhara Kurup, G; Sreejith, K

    1999-07-01

    L-asparaginase isolated in our laboratory fromAeromonas has been found to be antileukaemic. In the present study changes in the levels of serum enzymes in leukaemic mice and under treatment withAeromonas L-asparaginase has been compared. A significant increase in the levels of serum lactate dehydrogenase with tumour growth and a decrease during therapy was observed. A significant decrease in alanine transaminase activity during tumour growth and an increase during treatment was noticed. Increased levels of aspartate transaminase and alkaline phosphatase was observed during enzyme therapy. Total acid phosphatase was found to be increased during tumour growth and decreased considerably during treatment.

  7. Expression and purification of L-asparaginase from Escherichia coli and the inhibitory effects of cyclic dipeptides.

    Science.gov (United States)

    Zhang, Yanan; Li, Dan; Li, Yan

    2017-01-20

    L-asparaginase, a key enzyme involved in nitrogen metabolism, is an effective anti-tumour agent. Cyclic dipeptides, a group of compounds, contain several important biological functions. In this paper, we proposed a novel method for L-asparaginase expression and purification from Echerichia coli and determined the effect of cyclic dipeptides on the enzymatic activity of recombinant L-asparaginase. The gene ansB encoding L-asparaginase was amplified from the genome of E. coli BL21 (DE3) by polymerase chain reaction and sub-cloned into pET-15b vector to construct expressing plasmid pET-15b-ansB. The expression of recombinant protein was purified by affinity chromatography using a nickel resin followed by anion exchange chromatography. The purity and quality of the recombinant L-asparaginase were optimised. The results indicated that km for the recombinant L-asparaginase was 3.02 × 10(-4) mol/L. Both cyclo-(Pro-Tyr) and cyclo-(Pro-Phe) could inhibit the activity of recombinant L-asparaginase at the level of 10(-5) mol/L.

  8. E. coli-Derived L-Asparaginase Retains Enzymatic and Cytotoxic Activity In Vitro for Canine and Feline Lymphoma after Cold Storage

    Directory of Open Access Journals (Sweden)

    Jackie M. Wypij

    2013-01-01

    Full Text Available Background. L-asparaginase is effective in treating canine and feline lymphoma, however chemotherapy poses a significant financial cost to veterinary clients, limiting therapy for many pets. Single dose vials result in significant drug wastage, and drug shortages limit consistent availability for pets. Hypothesis. E. coli-derived asparaginase retains enzymatic and antineoplastic activity in canine and feline lymphoma cells after cold storage. Methods. E. coli-derived asparaginase was cold-stored: refrigeration (7–14 days and freezing (14 days–six months, one to three freeze/thaw cycles. Enzymatic activity of asparaginase was measured via a modified asparagine assay. Effects of cold-stored asparaginase on cell proliferation and cytotoxicity were measured in feline (MYA-1, F1B and canine (17–71, OSW lymphoma cells. Results. Cold-stored E. coli-derived asparaginase retains antineoplastic activity in all four cell lines tested. Cold-stored E. coli-derived L-asparaginase depletes asparagine and retains enzymatic activity. Duration of refrigeration, duration of freezing, and number of freeze-thaw cycles have minimal effect on asparaginase enzyme activity. Conclusions and Clinical Importance. This study establishes a scientific basis for long-term cold storage of reconstituted E. coli-derived asparaginase that may result in better utilization of limited drug resources and improve financial feasibility of E. coli-derived asparaginase as a therapeutic option for pets with lymphoma.

  9. Asparagine deprivation mediated by Salmonella asparaginase causes suppression of activation-induced T cell metabolic reprogramming.

    Science.gov (United States)

    Torres, AnnMarie; Luke, Joanna D; Kullas, Amy L; Kapilashrami, Kanishk; Botbol, Yair; Koller, Antonius; Tonge, Peter J; Chen, Emily I; Macian, Fernando; van der Velden, Adrianus W M

    2016-02-01

    Salmonellae are pathogenic bacteria that induce immunosuppression by mechanisms that remain largely unknown. Previously, we showed that a putative type II l-asparaginase produced by Salmonella Typhimurium inhibits T cell responses and mediates virulence in a murine model of infection. Here, we report that this putative L-asparaginase exhibits L-asparagine hydrolase activity required for Salmonella Typhimurium to inhibit T cells. We show that L-asparagine is a nutrient important for T cell activation and that L-asparagine deprivation, such as that mediated by the Salmonella Typhimurium L-asparaginase, causes suppression of activation-induced mammalian target of rapamycin signaling, autophagy, Myc expression, and L-lactate secretion. We also show that L-asparagine deprivation mediated by the Salmonella Typhimurium L-asparaginase causes suppression of cellular processes and pathways involved in protein synthesis, metabolism, and immune response. Our results advance knowledge of a mechanism used by Salmonella Typhimurium to inhibit T cell responses and mediate virulence, and provide new insights into the prerequisites of T cell activation. We propose a model in which l-asparagine deprivation inhibits T cell exit from quiescence by causing suppression of activation-induced metabolic reprogramming.

  10. Bio-grout based on microbially induced sand solidification by means of asparaginase activity.

    Science.gov (United States)

    Li, Mengmeng; Fu, Qing-Long; Zhang, Qiuzhuo; Achal, Varenyam; Kawasaki, Satoru

    2015-11-03

    Bio-grout, a new ground improvement method, has been recently developed to improve the mechanical properties, decrease the permeability of porous materials, reinforce or repair cementitious materials and modify the properties of soil or sand. Bio-grout production depends on microbially induced calcite precipitation (MICP), which is driven mainly by an enzyme, urease. However, urease-based MICP process produces excessive ammonia, in addition to secondary pollution generated by urea that is used as substrate in it. In the present study, we reported asparaginase-based MICP process for sand bio-grout development using Bacillus megaterium, and results were also compared with urease-based bio-grouts. The asparaginase activity led to significantly less ammonia production compared to urease without compromising with desired properties of a novel grout. The UCS of bio-grout was obtained at 980 kPa, while the permeability was decreased substantially. The mineralogical composition of precipitated substance was identified as calcite using XRD and the crystal morphology was observed under SEM. The mass percentage of calcite in bio-grout was calculated by thermogravimetric analysis and XCT verified calcite precipitation in it. The results confirmed that biocalcification by means of bacterial asparaginase is a potential solution for geotechnical problems. The asparaginase-based MICP process could be of wider acceptance in future.

  11. Bio-grout based on microbially induced sand solidification by means of asparaginase activity

    Science.gov (United States)

    Li, Mengmeng; Fu, Qing-Long; Zhang, Qiuzhuo; Achal, Varenyam; Kawasaki, Satoru

    2015-11-01

    Bio-grout, a new ground improvement method, has been recently developed to improve the mechanical properties, decrease the permeability of porous materials, reinforce or repair cementitious materials and modify the properties of soil or sand. Bio-grout production depends on microbially induced calcite precipitation (MICP), which is driven mainly by an enzyme, urease. However, urease-based MICP process produces excessive ammonia, in addition to secondary pollution generated by urea that is used as substrate in it. In the present study, we reported asparaginase-based MICP process for sand bio-grout development using Bacillus megaterium, and results were also compared with urease-based bio-grouts. The asparaginase activity led to significantly less ammonia production compared to urease without compromising with desired properties of a novel grout. The UCS of bio-grout was obtained at 980 kPa, while the permeability was decreased substantially. The mineralogical composition of precipitated substance was identified as calcite using XRD and the crystal morphology was observed under SEM. The mass percentage of calcite in bio-grout was calculated by thermogravimetric analysis and XCT verified calcite precipitation in it. The results confirmed that biocalcification by means of bacterial asparaginase is a potential solution for geotechnical problems. The asparaginase-based MICP process could be of wider acceptance in future.

  12. Current applications and different approaches for microbial L-asparaginase production

    Directory of Open Access Journals (Sweden)

    Jorge Javier Muso Cachumba

    Full Text Available ABSTRACT L-asparaginase (EC 3.5.1.1 is an enzyme that catalysis mainly the asparagine hydrolysis in L-aspartic acid and ammonium. This enzyme is presented in different organisms, such as microorganisms, vegetal, and some animals, including certain rodent's serum, but not unveiled in humans. It can be used as important chemotherapeutic agent for the treatment of a variety of lymphoproliferative disorders and lymphomas (particularly acute lymphoblastic leukemia (ALL and Hodgkin's lymphoma, and has been a pivotal agent in chemotherapy protocols from around 30 years. Also, other important application is in food industry, by using the properties of this enzyme to reduce acrylamide levels in commercial fried foods, maintaining their characteristics (color, flavor, texture, security, etc. Actually, L-asparaginase catalyzes the hydrolysis of L-asparagine, not allowing the reaction of reducing sugars with this aminoacid for the generation of acrylamide. Currently, production of L-asparaginase is mainly based in biotechnological production by using some bacteria. However, industrial production also needs research work aiming to obtain better production yields, as well as novel process by applying different microorganisms to increase the range of applications of the produced enzyme. Within this context, this mini-review presents L-asparaginase applications, production by different microorganisms and some limitations, current investigations, as well as some challenges to be achieved for profitable industrial production.

  13. Acrylamide reduction in fried potato slices and strips by using asparaginase in combination with conventional blanching

    DEFF Research Database (Denmark)

    Pedreschi, Franco; Risum, Jørgen; Granby, Kit

    of potato tissue leading to an easier and more effective diffusion of asparaginase. On the other hand, par-fried potatoes of Bintje variety were prepared by cutting strips (0.8×0.8×5cm) which were blanched at 75°C for 10min. Unblanched strips were used as the control. Control or blanched strips were...

  14. Erroneous exchange of asparaginase forms in the treatment of acute lymphoblastic leukemia

    NARCIS (Netherlands)

    Cheung, K.C.; Bemt, P.M. van den; Torringa, M.L.; Tamminga, R.Y.; Pieters, R.; Smet, P.A. de

    2011-01-01

    For the treatment of children with acute lymphoblastic leukemia (ALL), Dutch pediatric oncologists use the Dutch Childhood Oncology Group ALL 10 protocol. This protocol is complex, as it comprises many different drug regimens. One of the drugs is asparaginase which is available in different forms wi

  15. Erroneous Exchange of Asparaginase Forms in the Treatment of Acute Lymphoblastic Leukemia

    NARCIS (Netherlands)

    Cheung, Ka-Chun; van den Bemt, Patricia M. L. A.; Torringa, Maarten L. J.; Tamminga, Rienk Y. J.; Pieters, Rob; de Smet, Peter A. G. M.

    2011-01-01

    For the treatment of children with acute lymphoblastic leukemia (ALL), Dutch pediatric oncologists use the Dutch Childhood Oncology Group ALL 10 protocol. This protocol is complex, as it comprises many different drug regimens. One of the drugs is asparaginase which is available in different forms wi

  16. The K+-dependent asparaginase, NSE1, is crucial for plant growth and seed production in Lotus japonicus.

    Science.gov (United States)

    Credali, Alfredo; García-Calderón, Margarita; Dam, Svend; Perry, Jillian; Díaz-Quintana, Antonio; Parniske, Martin; Wang, Trevor L; Stougaard, Jens; Vega, José M; Márquez, Antonio J

    2013-01-01

    The physiological role of K(+)-dependent and K(+)-independent asparaginases in plants remains unclear, and the contribution from individual isoforms during development is poorly understood. We have used reverse genetics to assess the phenotypes produced by the deficiency of K(+)-dependent NSE1 asparaginase in the model legume Lotus japonicus. For this purpose, four different mutants were identified by TILLING and characterized, two of which affected the structure and function of the asparaginase molecule and caused asparagine accumulation. Plant growth and total seed weight of mature mutant seeds as well as the level of both legumin and convicilin seed storage proteins were affected in the mutants. The mutants isolated in the present work are the first of their type in legumes and have enabled us to demonstrate the importance of asparagine and K(+)-dependent NSE1 asparaginase for nitrogen remobilization and seed production in L. japonicus plants.

  17. Purification, characterization and kinetic properties of extracellular L-asparaginase produced by Cladosporium sp.

    Science.gov (United States)

    Mohan Kumar, N S; Manonmani, H K

    2013-04-01

    L-asparaginase from Cladosporium sp. grown on wheat bran by SSF was purified. Enzyme appeared to be a trimer with homodimer of 37 kDa and another 47 kDa amounting to total mass of 121 kDa as estimated by SDS-PAGE and 120 kDa on gel filtration column. The optimum temperature and pH of the enzyme were 30 °C and 6.3, respectively with Vmax of 4.44 μmol/mL/min and Km of 0.1 M. Substrate specificity studies indicated that, L-asparaginase has greater affinity towards L-asparagine with substrate hydrolysis efficiency (Vmax/Km ratio) eightfold higher than that of L-glutamine. L-asparaginase activity in presence of thiols studied showed decrease in Vmax and increase in Km, indicating nonessential mode of inactivation. Among the thiols tested, β-mercaptomethanol, exerted inhibitory effect, suggesting a critical role of disulphide linkages in maintaining a suitable conformation of the enzyme. Metal ions such as Ca(2+), Co(2+), Cu(2+), Mg(2+), Na(+), K(+) and Zn(2+) significantly affected enzyme activity whereas presence of Fe(3+), Pb(2+) and KI stimulated the activity. Detergents studied also enhanced L-asparaginase activity. In-vitro half-life of purified L-asparaginase in mammalian blood serum was 93.69 h. The enzyme inhibited acrylamide formation in potato chips by 96 % making it a potential candidate for food industry to reduce acrylamide content in starchy fried food commodities.

  18. Crystallization and preliminary crystallographic analysis of l-asparaginase from Erwinia carotovora

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Linnea E. K. [Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland); Krasotkina, Julya; Kuchumova, Anastasia; Sokolov, Nikolay N. [Institute for Biomedical Chemistry, Russian Academy of Medical Sciences, 559-B, 10 Pogodinskay St, Moscow 119121 (Russian Federation); Papageorgiou, Anastassios C., E-mail: tassos.papageorgiou@btk.fi [Turku Centre for Biotechnology, University of Turku and Åbo Akademi University, Turku 20521 (Finland)

    2005-04-01

    Er. carotovoral-asparaginase, a potential antileukaemic agent, has been crystallized. Crystals diffract to 2.6 Å using a rotating-anode source and belong to space group P2{sub 1}, with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. Bacterial l-asparaginases have been used as therapeutic agents in the treatment of acute childhood lymphoblastic leukaemia for over 30 y. However, their use is limited owing to the glutaminase activity of the administered enzymes, which results in serious side effects. In contrast, l-asparaginase from Erwinia carotovora exhibits low glutaminase activity at physiological concentrations of l-asparagine and l-glutamine in the blood. Recombinant Er. carotovoral-asparaginase was crystallized in the presence of l-glutamate by the hanging-drop vapour-diffusion method using 10 mg ml{sup −1} purified enzyme, 16–18%(w/v) PEG 3350 and 0.2 M NaF. X-ray diffraction data were collected to 2.6 Å at 293 K using an in-house rotating-anode generator. The crystals belong to the monoclinic P2{sub 1} space group, with unit-cell parameters a = 78.0, b = 112.3, c = 78.7 Å, β = 101.9° and a homotetramer in the crystallographic asymmetric unit. A molecular-replacement solution has been found and refinement is currently in progress. The crystal structure may provide leads towards protein-engineering efforts aimed at safer asparaginase administration in leukaemia treatment.

  19. Erwinia asparaginase achieves therapeutic activity after pegaspargase allergy: a report from the Children's Oncology Group.

    Science.gov (United States)

    Salzer, Wanda L; Asselin, Barbara; Supko, Jeffrey G; Devidas, Meenakshi; Kaiser, Nicole A; Plourde, Paul; Winick, Naomi J; Reaman, Gregory H; Raetz, Elizabeth; Carroll, William L; Hunger, Stephen P

    2013-07-25

    AALL07P2 evaluated whether substitution of Erwinia asparaginase 25000 IU/m(2) for 6 doses given intramuscularly Monday/Wednesday/Friday (M/W/F) to children and young adults with acute lymphoblastic leukemia and clinical allergy to pegaspargase would provide a 48-hour nadir serum asparaginase activity (NSAA) ≥ 0.10 IU/mL. AALL07P2 enrolled 55 eligible/evaluable patients. NSAA ≥ 0.1 IU/mL was achieved in 38 of 41 patients (92.7%) with acceptable samples 48 hours and in 38 of 43 patients (88.4%) 72 hours after dosing during course 1. Among samples obtained during all courses, 95.8% (252 of 263) of 48-hour samples and 84.5% (125 of 148) of 72-hour samples had NSAA ≥ 0.10-IU/mL. Pharmacokinetic parameters were estimated by fitting the serum asparaginase activity-time course for all 6 doses given during course 1 to a 1-compartment open model with first order absorption. Erwinia asparaginase administered with this schedule achieved therapeutic NSAA at both 48 and 72 hours and was well tolerated with no reports of hemorrhage, thrombosis, or death, and few cases of grade 2 to 3 allergic reaction (n = 6), grade 1 to 3 hyperglycemia (n = 6), or grade 1 pancreatitis (n = 1). Following allergy to pegaspargase, Erwinia asparaginase 25000 IU/m(2) × 6 intramuscularly M/W/F can be substituted for a single dose of pegaspargase.

  20. Molecular expression of l-asparaginase gene from Nocardiopsis alba NIOT-VKMA08 in Escherichia coli: A prospective recombinant enzyme for leukaemia chemotherapy.

    Science.gov (United States)

    Meena, Balakrishnan; Anburajan, Lawrance; Vinithkumar, Nambali Valsalan; Shridhar, Divya; Raghavan, Rangamaran Vijaya; Dharani, Gopal; Kirubagaran, Ramalingam

    2016-09-30

    l-Asparaginase is an antineoplastic agent that selectively reduces the level of l-asparagine in blood and diminishes the proliferation of cancerous cells. Studies were carried out on the cloning and heterologous expression of l-asparaginase biosynthesis gene (ansA) from Nocardiopsis alba NIOT-VKMA08 to achieve the stable inducible system that overproduces the glutaminase-free recombinant l-asparaginase. Overexpression of recombinant l-asparaginase was achieved with an optimized final concentration of 1.5mM of isopropyl-β-d-thiogalactoside (IPTG) and the enzyme was expressed as a soluble protein. The recombinant enzyme was purified using nickel-nitrilotriacetic acid (Ni-NTA) chromatography and the purified enzyme disclosed an elevated level of asparaginase activity (158.1IU/mL). Optimum pH and temperature of the purified l-asparaginase for the hydrolysis of l-asparagine were 8.0 and 37°C and it was very specific for its natural substrate, l-asparagine. Detailed studies were carried out on the kinetics of enzyme reaction, catalytic activity, temperature and ionic strength and the thermostability of the l-asparaginase enzyme. The functional characterisation of the recombinant l-asparaginase was studied through Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), in silico sequence analysis and protein structural modelling. Glutaminase activity was not detected in the recombinant l-asparaginase, which could reduce the probable side effects during leukaemia therapy.

  1. Application of repeated aspartate tags to improving extracellular production of Escherichia coli L-asparaginase isozyme II.

    Science.gov (United States)

    Kim, Sun-Ki; Min, Won-Ki; Park, Yong-Cheol; Seo, Jin-Ho

    2015-11-01

    Asparaginase isozyme II from Escherichia coli is a popular enzyme that has been used as a therapeutic agent against acute lymphoblastic leukemia. Here, fusion tag systems consisting of the pelB signal sequence and various lengths of repeated aspartate tags were devised to highly express and to release active asparaginase isozyme II extracellularly in E. coli. Among several constructs, recombinant asparaginase isozyme II fused with the pelB signal sequence and five aspartate tag was secreted efficiently into culture medium at 34.6 U/mg cell of specific activity. By batch fermentation, recombinant E. coli produced 40.8 U/ml asparaginase isozyme II in the medium. In addition, deletion of the gspDE gene reduced extracellular production of asparaginase isozyme II, indicating that secretion of recombinant asparaginase isozyme II was partially ascribed to the recognition by the general secretion machinery. This tag system composed of the pelB signal peptide, and repeated aspartates can be applied to extracellular production of other recombinant proteins.

  2. Safety, efficacy, and clinical utility of asparaginase in the treatment of adult patients with acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Koprivnikar J

    2017-03-01

    Full Text Available Jamie Koprivnikar, James McCloskey, Stefan Faderl Division of Leukemia, John Theurer Cancer Center at Hackensack University Medical Center, Hackensack, NJ, USA Abstract: Adults with acute lymphoblastic leukemia (ALL are known to have inferior outcomes compared to the pediatric population. Although the reasons for this are likely manyfold, the agents utilized and the increased intensity of pediatric treatments compared to adult treatments are likely significant contributing factors. Asparaginase, an enzyme that converts asparagine to aspartic acid, forms the backbone of almost all pediatric regimens and works by depleting extracellular asparagine, which ALL cells are unable to synthesize. Asparaginase toxicities, which include hypersensitivity reactions, pancreatitis, liver dysfunction, and thrombosis, have hindered its widespread use in the adult population. Here, we review the toxicity and efficacy of asparaginase in adult patients with ALL. With the proper precautions, it is a safe and effective agent in the treatment of younger adults with ALL with response rates in the frontline setting ranging from 78% to 96%, compared to most trials showing a 4-year overall survival of 50% or better. The age cutoff for consideration of treatment with pediatric-inspired regimens is not clear, but recent studies show promise particularly in the adolescent and young adult population. New formulations of asparaginase are actively in development, including erythrocyte-encapsulated asparaginase, which is designed to minimize the toxicity and improve the delivery of the drug. Keywords: PEG-asparaginase, ALL, chemotherapy, pegaspargase, AYA, pediatric 

  3. Acrylamide reduction in potato chips by using commercial asparaginase in combination with conventional blanching

    DEFF Research Database (Denmark)

    Pedreschi, Franco; Mariotti, Salomé; Granby, Kit

    2011-01-01

    ). Prior to frying, potato slices were treated in one of the following ways: (i) Rinsing in distilled water (control I); (ii) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min; (iii) Rinsing in distilled water plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C...... for 20 min; (iv) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in an asparaginase solution (10000 ASNU/L) at 50 °C for 20 min; (v) Rinsing in distilled water plus blanching in hot water at 85 °C for 3.5 min plus immersion in distilled water at 50 °C for 20 min...

  4. Acute Pancreatitis and Diabetic Ketoacidosis following L-Asparaginase/Prednisone Therapy in Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Dania Lizet Quintanilla-Flores

    2014-01-01

    Full Text Available Acute pancreatitis and diabetic ketoacidosis are unusual adverse events following chemotherapy based on L-asparaginase and prednisone as support treatment for acute lymphoblastic leukemia. We present the case of a 16-year-old Hispanic male patient, in remission induction therapy for acute lymphoblastic leukemia on treatment with mitoxantrone, vincristine, prednisone, and L-asparaginase. He was hospitalized complaining of abdominal pain, nausea, and vomiting. Hyperglycemia, acidosis, ketonuria, low bicarbonate levels, hyperamylasemia, and hyperlipasemia were documented, and the diagnosis of diabetic ketoacidosis was made. Because of uncertainty of the additional diagnosis of acute pancreatitis as the cause of abdominal pain, a contrast-enhanced computed tomography was performed resulting in a Balthazar C pancreatitis classification.

  5. Cerebrospinal fluid asparagine depletion during pegylated asparaginase therapy in children with acute lymphoblastic leukaemia

    DEFF Research Database (Denmark)

    Henriksen, Louise T; Nersting, Jacob; Raja, Raheel A;

    2014-01-01

    . The objective of this study was to describe CSF asparagine depletion during 30 weeks of pegylated asparaginase therapy, 1000 iu/m(2) i.m. every second week, and to correlate CSF asparagine concentration with serum L-asparaginase enzyme activity. Danish children (1-17 years) with ALL, treated according...... asparagine concentration decreased from a pre-treatment level of 5·3 μmol/l to median levels ≤1·5 μmol/l. However, only 4/31 patients (five samples) had CSF asparagine concentrations below the limit of detection (0·1 μmol/l). In 11 patients, 24 paired same day serum and CSF samples were obtained. A decrease...

  6. Lipid metabolism in tumour bearing mice treated withAeromonas L-asparaginase.

    Science.gov (United States)

    Benny, P J; Kurup, G M; Sreejith, K

    1997-07-01

    The anticancerous drug isolated in our laboratory from estuarineAeromonas was characterised and is found to be an enzyme, L-asparaginase. The antileukaemic effect of this drug was studied in mice by inducing leukaemia with Ehrlich ascites cell lines. It was compared with commercially available drug, Leunase, isolated fromE. coli. The lipid profiles in mice during leukaemia and under treatment was studied. The decreased levels of cholesterol and increased levels of triglycerides and phospholipids in serum, liver and kidney were observed in tumour bearing mice. Significant changes in the above values were observed with enzyme therapy. It could bring some of the values to near normal level. L-asparaginase fromAeromonas was found to be more effective.

  7. Venous thromboembolism following L-asparaginase treatment for lymphoid malignancies in Korea.

    Science.gov (United States)

    Lee, J H; Lee, J; Yhim, H-Y; Oh, D; Bang, S-M

    2017-02-02

    Essentials Data on venous thromboembolism (VTE) after L-asparaginase (L-asp) in Asian lymphoma are scarce. This is a population-based study in Asian patients with lymphoid disease and L-asp-related VTE. The overall incidence of L-asp-associated VTE was similar to reports on Caucasians. This first and largest study in Asians shows that mainly adult patients are at risk of thrombosis.

  8. Sequential Administration of Methotrexate and Asparaginase in Relapsed or Refractory Pediatric Acute Myeloid Leukemia

    Science.gov (United States)

    Buaboonnam, Jassada; Cao, Xueyuan; Pauley, Jennifer L.; Pui, Ching-Hon; Ribeiro, Raul C.; Rubnitz, Jeffrey E.; Inaba, Hiroto

    2014-01-01

    Background The efficacy of combination chemotherapy with methotrexate (MTX) and asparaginase is not well known in relapsed and refractory acute leukemia after contemporary therapy. Procedure A retrospective study of pediatric patients with relapsed or refractory acute myeloid leukemia (AML) who received MTX and asparaginase as a salvage therapy at St. Jude Children Research Hospital was performed. MTX was given intravenously followed by a dose of asparaginase intramuscularly or intravenously 24 hours later. The chemotherapy cycle was repeated every 7-10 days. Response, survival, and toxicities were evaluated. Results Fifteen patients, median age 10.5 years (range, 1.1-18.5 years), were treated. Median number of previous therapeutic regimens was 3 (range, 1-4). Six patients responded to treatment (3 had morphologic complete remission with incomplete blood count recovery, 2 had partial remission, and 1 had stable disease for 16 months), and 4 are still alive. Three of 6 responders had monoblastic leukemia, and also developed tumor lysis syndrome. The 1- and 2-year overall survival rates are 35.6% and 17.8%, respectively. The most common adverse event was transient elevation of transaminases (9 patients). Two patients developed pancreatitis. Episodes of febrile neutropenia were rare (2 patients), and most courses (75 out of 93 total courses) were given in an outpatient setting. Conclusions Combination chemotherapy with MTX and asparaginase appears to be an effective salvage therapy and well tolerated in patients with relapsed or refractory childhood AML, even in those heavily pretreated with contemporary frontline or salvage therapy. PMID:23335430

  9. Direct long-term effects of L-asparaginase on rat and human pancreatic islets

    DEFF Research Database (Denmark)

    Clausen, Niels; Nielsen, Jens Høiriis

    1989-01-01

    L-Asparaginase, an effective agent in the treatment of acute lymphoblastic leukemia, may induce a diabetic state. The pathogenesis of the diabetogenic effect was studied in cultured pancreatic islets. Mean serum concentrations in three children with acute lymphoblastic leukemia were 2.4 U/mL (range...... 1.4-4.5) before and 31.5 U/mL (range 18.6-51.8) immediately after an intravenous injection of 1000 U/kg L-asparaginase. Glucose-induced insulin release from pancreatic islets of rat and man was measured after 3 and 7 days of culture in media with or without clinically relevant concentrations...... of Escherichia coli L-asparaginase (0.01-100 U/mL). After culture, the remaining insulin, glucagon, and DNA in the islets were determined. After 7 days of culture of adult rat or human islets, both the accumulation of insulin in the medium and the content of insulin and glucagon in the islets were significantly...

  10. Optimization, purification, and characterization of L-asparaginase from Actinomycetales bacterium BkSoiiA.

    Science.gov (United States)

    Dash, Chitrangada; Mohapatra, Sukanti Bala; Maiti, Prasanta Kumar

    2016-01-01

    Actinobacteria are promising source of a wide range of important enzymes, some of which are produced in industrial scale, with others yet to be harnessed. L-Asparaginase is used as an antineoplastic agent. The present work deals with the production and optimization of L-asparaginase from Actinomycetales bacterium BkSoiiA using submerged fermentation in M9 medium. Production optimization resulted in a modified M9 medium with yeast extract and fructose as carbon and nitrogen sources, respectively, at pH 8.0, incubated for 120 hr at 30 ± 2 °C. The crude enzyme was purified to near homogeneity by ammonium sulfate precipitation following dialysis, ion-exchange column chromatography, and finally gel filtration. The sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis (PAGE) revealed an apparent molecular weight of 57 kD. The enzyme was purified 95.06-fold and showed a final specific activity of 204.37 U/mg with 3.49% yield. The purified enzyme showed maximum activity at a pH 10.0 and was stable at pH 7.0 to 9.0. The enzyme was activated by Mn(2+) and strongly inhibited by Ba(2+). All these preliminary characterization suggests that the L-asparaginase from the source may be a tool useful to pharmaceutical industries after further research.

  11. Molecular Cloning, Biochemical Characterization, and Antitumor Properties of a Novel L-Asparaginase from Synechococcus elongatus PCC6803.

    Science.gov (United States)

    Kebeish, R; El-Sayed, A; Fahmy, H; Abdel-Ghany, A

    2016-10-01

    L-asparaginase (EC 3.5.1.1), which catalyzes the deamidation of L-asparagine to L-aspartic acid and ammonia, has been widely used as a key therapeutic tool in the treatment of tumors. The current commercially available L-asparaginases, produced from bacteria, have signs of toxicity and hypersensitivity reactions during the course of tumor therapy. Therefore, searching for L-asparaginases with unique biochemical properties and fewer adverse effects was the objective of this work. In this study, cyanobacterial strain Synechococcus elongatus PCC6803 was found as a novel source of L-asparaginase. The L-asparaginase gene coding sequence (gi:939195038) was cloned and expressed in E. coli BL21(DE3), and the recombinant protein (Se.ASPII) was purified by affinity chromatography. The enzyme has high affinity towards L-asparagine and shows very weak affinity towards L-glutamine. The enzymatic properties of the recombinant enzyme were investigated, and the kinetic parameters (Km, Vmax) were measured. The pH and temperature dependence profiles of the novel enzyme were analyzed. The work was extended to measure the antitumor properties of the novel enzyme against different human tumor cell lines.

  12. Calcium and adenosine triphosphate control of cellular pathology: asparaginase-induced pancreatitis elicited via protease-activated receptor 2

    Science.gov (United States)

    Peng, Shuang; Gerasimenko, Julia V.; Tsugorka, Tatiana; Gryshchenko, Oleksiy; Samarasinghe, Sujith; Gerasimenko, Oleg V.

    2016-01-01

    Exocytotic secretion of digestive enzymes from pancreatic acinar cells is elicited by physiological cytosolic Ca2+ signals, occurring as repetitive short-lasting spikes largely confined to the secretory granule region, that stimulate mitochondrial adenosine triphosphate (ATP) production. By contrast, sustained global cytosolic Ca2+ elevations decrease ATP levels and cause necrosis, leading to the disease acute pancreatitis (AP). Toxic Ca2+ signals can be evoked by products of alcohol and fatty acids as well as bile acids. Here, we have investigated the mechanism by which l-asparaginase evokes AP. Asparaginase is an essential element in the successful treatment of acute lymphoblastic leukaemia, the most common type of cancer affecting children, but AP is a side-effect occurring in about 5–10% of cases. Like other pancreatitis-inducing agents, asparaginase evoked intracellular Ca2+ release followed by Ca2+ entry and also substantially reduced Ca2+ extrusion because of decreased intracellular ATP levels. The toxic Ca2+ signals caused extensive necrosis. The asparaginase-induced pathology depended on protease-activated receptor 2 and its inhibition prevented the toxic Ca2+ signals and necrosis. We tested the effects of inhibiting the Ca2+ release-activated Ca2+ entry by the Ca2+ channel inhibitor GSK-7975A. This markedly reduced asparaginase-induced Ca2+ entry and also protected effectively against the development of necrosis. This article is part of the themed issue ‘Evolution brings Ca2+ and ATP together to control life and death’. PMID:27377732

  13. A rapid, efficient and sensitive plate assay for detection and screening of l-asparaginase-producing microorganisms.

    Science.gov (United States)

    Mahajan, Richi V; Saran, Saurabh; Saxena, Rajendra K; Srivastava, Ayush K

    2013-04-01

    l-Asparaginase-producing microbes are conventionally screened on phenol red l-asparagine-containing plates. However, sometimes the contrast of the zone obtained (between yellow and pink) is not very sharp and distinct. In the present investigation, an improved method for screening of the microorganisms producing extracellular l-asparaginase is reported wherein bromothymol blue (BTB) is incorporated as pH indicator in l-asparagine-containing medium instead of phenol red. Plates containing BTB at acidic pH are yellow and turn dark blue at alkaline pH. Thus, a dense dark blue zone is formed around microbial colonies producing l-asparaginase, differentiating between enzyme producers and non-producers. The present method is more sensitive and accurate than the conventional method for screening of both fungi and bacteria producing extracellular l-asparaginase. Furthermore, BTB gives a transient green colour at neutral pH (7.0) and dark blue colour at higher pH 8.0-9.0, indicating the potency of the microorganism for l-asparaginase production.

  14. The potential of halophilic and halotolerant bacteria for the production of antineoplastic enzymes: L-asparaginase and L-glutaminase

    Science.gov (United States)

    Shirazian, Pejman; Asad, Sedigheh; Amoozegar, Mohammad Ali

    2016-01-01

    L-asparaginase and L-glutaminase can be effectively used for the treatment of patients who suffer from accute lymphoblastic leukemia and tumor cells. Microbial sources are the best source for the bulk production of these enzymes. However, their long-term administration may cause immunological responses, so screening for new enzymes with novel properties is required. Halophilic and halotolerant bacteria with novel enzymatic characteristics can be considered as a potential source for production of enzymes with different immunological properties. In this study, L-asparaginase and L-glutaminase production by halophilic bacteria isolated from Urmia salt lake was studied. Out of the 85 isolated halophilic and halotolerant bacterial strains, 16 (19 %) showed L-asparaginase activity and 3 strains (3.5 %) showed L-glutaminase activity. Strains with the highest activities were selected for further studies. Based on 16S rDNA sequence analysis, it was shown that the selected isolates for L-asparaginase and L-glutaminase production belong to the genus Bacillus and Salicola, respectively. Both enzymes were produced extracellularly. The strain with the most L-asparaginase production did not show L-glutaminase production which is medically important. The effects of key parameters including temperature, initial pH of the solution, and concentrations of glucose, asparagine or glutamine, and sodium chloride were evaluated by means of response surface methodology (RSM) to optimize enzymes production. Under the obtained optimal conditions, L-asparaginase and L-glutaminase production was increased up to 1.5 (61.7 unit/mL) and 2.6 fold (46.4 unit/mL), respectively. PMID:27330530

  15. Biochemical characterization of a novel L-asparaginase from Paenibacillus barengoltzii being suitable for acrylamide reduction in potato chips and mooncakes.

    Science.gov (United States)

    Shi, Ran; Liu, Yu; Mu, Qing; Jiang, Zhengqiang; Yang, Shaoqing

    2017-03-01

    A novel L-asparaginase gene (PbAsnase) from Paenibaeillus barengoltzii CAU904 was cloned and expressed in Escherichia coli. The L-asparaginase gene was 1011bp encoding 336 amino acids. Multiple sequence alignment of PbAsnase with other known L-asparaginases revealed that the enzyme showed high similarities with some Rhizobial-type L-asparaginases, sharing the highest identity of 32% with a characterized L-asparaginase from Rhizobium etli CFN 42, suggesting that it should be a novel L-asparaginase. The recombinant L-asparaginase (PbAsnase) was purified to homogeneity and biochemically characterized. The purified enzyme was optimally active at pH 8.5 and 45°C, respectively. It was stable within pH 5.5-10.0 and at temperatures below 55°C. PbAsnase exhibited strict substrate specificity towards L-asparagine (35.2U/mg), with Km and Vmax values of 3.6mM and 162.2μmol/min/mg, respectively, but displayed trace activity towards L-glutamine. Moreover, the application potential of PbAsnase on acrylamide migration in potato chips and mooncakes was evaluated. The pretreatment by PbAsnase significantly decreased the acrylamide contents in potato chips and mooncakes by 86% and 52%, respectively. The unique properties of PbAsnase may make it a good candidate in industries, especially in food safety.

  16. [The feasibility of Erwinia asparaginase for pediatric patients who developed an allergic reaction to E.coli asparaginase during treatment of acute lymphoblastic leukemia].

    Science.gov (United States)

    Takahashi, Hiroyoshi; Koh, Katsuyoshi; Kato, Motohiro; Isobe, Kiyotaka; Yasui, Naoko; Mori, Makiko; Akiyama, Kosuke; Kikuchi, Akira; Hanada, Ryoji

    2013-04-01

    Asparaginase (ASNase) is one of the most important key drugs in the treatment of acute lymphoblastic leukemia (ALL). However, clinical hypersensitivity reactions often occur and lead to the discontinuation of ASNase treatment. Here, we report a retrospective study of 68 Erwinia ASNase (Erw-ASNase) administrations in 11 patients with childhood ALL who developed allergic reactions to E.coli-ASNase in our hospital between 2006 and 2012. The median age of the patients was 6 (range, 0 to 14). Erw-ASNase purchased overseas by the patients' guardians had already been administered when we obtained informed consent from the guardians. In all patients, fibrinogen and/or anti-thrombin III levels were decreased, but thrombosis did not develop. There was only one mild adverse event (grade 2 urticaria) in one patient, in whom Erw-ASNase could be continued after increasing the doses of premedication with antihistamine and prednisolone. Erw-ASNase could be safely administered to all patients.

  17. Screening of Actinomycetes from mangrove ecosystem for L-asparaginase activity and optimization by response surface methodology.

    Science.gov (United States)

    Usha, Rajamanickam; Mala, Krishnaswami Kanjana; Venil, Chidambaram Kulandaisamy; Palaniswamy, Muthusamy

    2011-01-01

    Marine actinomycetes were isolated from sediment samples collected from Pitchavaram mangrove ecosystem situated along the southeast coast of India. Maximum actinomycete population was noted in rhizosphere region. About 38% of the isolates produced L-asparaginase. One potential strain KUA106 produced higher level of enzyme using tryptone glucose yeast extract medium. Based on the studied phenotypic characteristics, strain KUA106 was identified as Streptomyces parvulus KUA106. The optimization method that combines the Plackett-Burman design, a factorial design and the response surface method, which were used to optimize the medium for the production of L-asparaginase by Streptomycetes parvulus. Four medium factors were screened from eleven medium factors by Plackett-Burman design experiments and subsequent optimization process to find out the optimum values of the selected parameters using central composite design was performed. Asparagine, tryptone, d) extrose and NaCl components were found to be the best medium for the L-asparaginase production. The combined optimization method described here is the effective method for screening medium factors as well as determining their optimum level for the production of L-asparaginase by Streptomycetes parvulus KUAP106.

  18. Therapeutic Efficacy of L-asparaginase in the Treatment of Refractory Midfacial Peripheral T-Cell Non-Hodgkin's Lymphoma

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To improve the efficacy of refractory midfacial peripheral T-cell non-Hodgkin's lymphoma (MPTC-NHL) with L-asparaginase (L-ASP) based salvage chemotherapy. Methods: 21 patients with refractory MPTC-NHL were analyzed. 11patients (L-ASP group) received L-asparaginase based salvage chemotherapy consisting of L-asparaginase, vincristine and dexame-thosone. 10 patients (control group) received salvage combination chemotherapy without L-asparaginase. Results: Complete remission rates were 45.6% for L-ASP group and 0.0% for control group (p<0.05). Overall response rates (CR+PR) were 63.6% for L-ASP group and 10.0% for control group, respectively (p<0.05). 2-year survival rates were 45.5% for L-ASP group and 0.0% for control group (p<0.05). The major adverse effects of L-ASP were leukopenia, elevation of serum bilirubin and hyperglycemia. Conclusion: The preliminary clinical study shows that the L-ASP based salvage chemotherapy may improve the response rate and 2-year survival rate of the patients with refractory MPTC-NHL. It is necessary to continue the study further.

  19. The Effects of L-Asparaginase on Blood Triglycerides, Glucose, and Albumin Levels and Coagulation State in ALL Patients in Pediatric Ward

    Directory of Open Access Journals (Sweden)

    Heydarian Farhad

    2009-10-01

    Full Text Available Asparaginase is one of the most important agents in the treatment of ALL. However, it has some side effects including dislipidemia, hyperglycemia, coagulopathy and hepatotoxicity. We studied its side ef-fects on our patients. The effects of L-asparaginase were assessed on 25 new ALL patients (case group and 25 patients with known ALL who had completed their treatment before. Sixty two percent of cases were male and remainder was female. The mean age of patients was 7.2 ± 3.8 years. In our patients, there was a rise in triglycerides (TG was seen following L- asparaginase administration (P = 0.02. Also, PT prolongation (P = 0.02 and hypoalbominemia (P = 0.002 were detected which could PT prolongation and hypoalbuminemia may be seen with L-asparaginase therapy that can be prevented with transfusion of FFP. Hypertriglyceridemia is often asymptomatic with no need for therapy.

  20. Screening and characterization of extracelluar L-asparaginase producing Bacillus subtilis strain hswx88, isolated from Taptapani hotspring of Odisha, India

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    Biswaprakash Pradhan

    2013-12-01

    Conclusion: The isolate is eco-friendly and useful to produce bulk quantity of extracellular, thermophilic L-asparaginase for the treatment of various tumor cases and for preparation of acrylamide free fry food preparation.

  1. Reduction of acrylamide level through blanching with treatment by an extremely thermostable L-asparaginase during French fries processing.

    Science.gov (United States)

    Zuo, Shaohua; Zhang, Tao; Jiang, Bo; Mu, Wanmeng

    2015-07-01

    Bacterial L-asparaginase catalyzes the hydrolysis of L-asparagine to L-aspartic acid. It is normally used as an antineoplastic drug applied in lymphoblastic leukemia chemotherapy and as a food processing aid in baked or fried food industry to inhibit the formation of acrylamide. The present study demonstrates cloning, expression, and characterization of a thermostable L-asparaginase from Thermococcus zilligii AN1 TziAN1_1 and also evaluates the potential for enzymatic acrylamide mitigation in French fries using this enzyme. The recombinant L-asparaginase was purified to homogeneity by nickel-affinity chromatography. The purified enzyme displayed the maximum activity at pH 8.5 and 90 °C, and the optimum temperature was the highest ever reported. The K m, k cat, and k cat/K m values toward L-asparagine were measured to be 6.08 mM, 3267 s(-1), and 537.3 mM(-1) s(-1), respectively. The enzyme retained 70 % of its original activity after 2 h of incubation at 85 °C. When potato samples were treated with 10 U/mL of L-asparaginase at 80 °C for only 4 min, the acrylamide content in final French fries was reduced by 80.5 % compared with the untreated control. Results of this study revealed that the enzyme was highly active at elevated temperatures, reflecting the potential of the T. zilligii L-asparaginase in the food processing industry.

  2. Optimization of Growth Conditions for Purification and Production of L-Asparaginase by Spirulina maxima

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    Hanaa H. Abd El Baky

    2016-01-01

    Full Text Available L-asparaginase (L-AsnA is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form concentrations (1.25, 2.50, and 5.0 g/L for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2 showed a high AsnA enzyme activity (898 IU, total protein (405 mg/g, specific enzyme activity (2.21 IU/mg protein, and enzyme yield (51.28 IU/L compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima.

  3. Optimization of Growth Conditions for Purification and Production of L-Asparaginase by Spirulina maxima.

    Science.gov (United States)

    Abd El Baky, Hanaa H; El Baroty, Gamal S

    2016-01-01

    L-asparaginase (L-AsnA) is widely distributed among microorganisms and has important applications in medicine and in food technology sectors. Therefore, the ability of the production, purification, and characterization of AsnA from Spirulina maxima (SM) were tested. SM cultures grown in Zarrouk medium containing different N2 (in NaNO3 form) concentrations (1.25, 2.50, and 5.0 g/L) for 18 days contained a significant various quantity of dry biomass yields and AsnA enzyme levels. MS L-AsnA activity was found to be directly proportional to the N2 concentration. The cultures of SM at large scales (300 L medium, 5 g/L N2) showed a high AsnA enzyme activity (898 IU), total protein (405 mg/g), specific enzyme activity (2.21 IU/mg protein), and enzyme yield (51.28 IU/L) compared with those in low N2 cultures. The partial purification of crude MS AsnA enzyme achieved by 80% ammonium sulfate AS precipitated and CM-Sephadex C-200 gel filtration led to increases in the purification of enzyme with 5.28 and 10.91 times as great as that in SM crude enzymes. Optimum pH and temperature of purified AsnA for the hydrolyzate were 8.5 and 37 ± 0.2°C, respectively. To the best of our knowledge, this is the first report on L-asparaginase production in S. maxima.

  4. [Suppression of telomerase activity leukemic cells by mutant forms of Rhodospirillum rubrum L-asparaginase].

    Science.gov (United States)

    Pokrovskaya, M V; Zhdanov, D D; Eldarov, M A; Aleksandrova, S S; Veselovskiy, A V; Pokrovskiy, V S; Grishin, D V; Gladilina, Ju A; Sokolov, N N

    2017-01-01

    The active and stable mutant forms of short chain cytoplasmic L-asparaginase type I of Rhodospirillum rubrum (RrA): RrA+N17, D60K, F61L, RrA+N17, A64V, E67K, RrA+N17, E149R, V150P, RrAE149R, V150P and RrAE149R, V150P, F151T were obtained by the method of site-directed mutagenesis. It is established that variants RrA-N17, E149R, V150P, F151T and RrАE149R, V150P are capable to reduce an expression hTERT subunit of telomerase and, hence, activity of telomeres in Jurkat cells, but not in cellular lysates. During too time, L-asparaginases of Escherichia coli, Erwinia carotovora and Wolinella succinogenes, mutant forms RrА+N17, D60K, F61L and RrА+N17, A64V, E67K do not suppress of telomerase activity. The assumption of existence in structure RrA of areas (amino acids residues in the position 146-164, 1-17, 60-67) which are responsible for suppression of telomerase activity is made. The received results show that antineoplastic activity of some variants RrA is connected both with reduction of concentration of free L-asparagine, and with expression suppression of hTERT telomerase subunit, that opens new prospects for antineoplastic therapy.

  5. Purification, characterization, cytotoxicity and anticancer activities of L-asparaginase, anti-colon cancer protein, from the newly isolated alkaliphilic Streptomyces fradiae NEAE-82

    Science.gov (United States)

    El-Naggar, Noura El-Ahmady; Deraz, Sahar F.; Soliman, Hoda M.; El-Deeb, Nehal M.; El-Ewasy, Sara M.

    2016-01-01

    L-asparaginase is an important enzyme as therapeutic agents used in combination with other drugs in the treatment of acute lymphoblastic leukemia. A newly isolated actinomycetes strain, Streptomyces sp. NEAE-82, was potentially producing extracellular L-asparaginase, it was identified as Streptomyces fradiae NEAE-82, sequencing product was deposited in the GenBank database under accession number KJ467538. L-asparaginase was purified from the crude enzyme using ammonium sulfate precipitation, dialysis and ion exchange chromatography using DEAE Sepharose CL-6B. Further the kinetic studies of purified enzyme were carried out. The optimum pH, temperature and incubation time for maximum L-asparaginase activity were found to be 8.5, 40 °C and 30 min, respectively. The optimum substrate concentration was found to be 0.06 M. The Km and Vmax of the enzyme were 0.01007 M and 95.08 Uml−1min−1, respectively. The half-life time (T1/2) was 184.91 min at 50 °С, while being 179.53 min at 60 °С. The molecular weight of the subunits of L-asparaginase was found to be approximately 53 kDa by SDS–PAGE analysis. The purified L-asparaginase showed a final specific activity of 30.636 U/mg protein and was purified 3.338-fold. The present work for the first time reported more information in the production, purification and characterization of L-asparaginase produced by newly isolated actinomycetes Streptomyces fradiae NEAE-82. PMID:27605431

  6. Expanding targets for a metabolic therapy of cancer: L-asparaginase.

    Science.gov (United States)

    Covini, Daniele; Tardito, Saverio; Bussolati, Ovidio; Chiarelli, Laurent R; Pasquetto, Maria V; Digilio, Rita; Valentini, Giovanna; Scotti, Claudia

    2012-01-01

    The antitumour enzyme L-asparaginase (L-asparagine amidohydrolase, EC 3.5.1.1, ASNase), which catalyses the deamidation of L-asparagine (Asn) to L-aspartic acid and ammonia, has been used for many years in the treatment of acute lymphoblastic leukaemia. Also NK tumours, subtypes of myeloid leukaemias and T-cell lymphomas respond to ASNase, and ovarian carcinomas and other solid tumours have been proposed as additional targets for ASNase, with a potential role for its glutaminase activity. The increasing attention devoted to the antitumour activity of ASNase prompted us to analyse recent patents specifically concerning this enzyme. Here, we first give an overview of metabolic pathways affected by Asn and Gln depletion and, hence, potential targets of ASNase. We then discuss recent published patents concerning ASNases. In particular, we pay attention to novel ASNases, such as the recently characterised ASNase produced by Helicobacter pylori, and those presenting amino acid substitutions aimed at improving enzymatic activity of the classical Escherichia coli enzyme. We detail modifications, such as natural glycosylation or synthetic conjugation with other molecules, for therapeutic purposes. Finally, we analyse patents concerning biotechnological protocols and strategies applied to production of ASNase as well as to its administration and delivery in organisms.

  7. Screening of Streptomycetes for L-Asparaginase, Therapeutic Agent of Lymphocytic Leukemia from Western Ghats of Karnataka, India

    Directory of Open Access Journals (Sweden)

    Mamatha B Salimath

    2016-03-01

    Full Text Available Actinomycetes are the most economically and biotechnologically valuable prokaryotes and are responsible for the production of about half of the discovered bioactive secondary metabolites, antibiotics, anticancer agents and enzymes. The present study was successful in characterizing 25 Streptomycetes isolates inhabiting Agumbe province, of Western Ghats soil of Karnataka, India, for potential source of L-asparaginase enzyme. L- Asparaginase (L-asparagine amido hydrolase E.C.3.5.1.1 is an extracellular enzyme has anti-carcinogenic potential, received increasing awareness in the current years because of its use as an effective agent against Acute Lymphocytic Leukemia (ALL. L-asparagine is a source of essential amino acid necessary for the growth of leukemic cells in higher amounts. Depletion of L-asparagine from the circulatory blood leads to death of malignant cells. Streptomyces isolates have been collected from soil samples by serial dilution and plating method employing Starch Casein Nitrate agar and ISP media. They were identified based on cultural, morphological and biochemical characteristics. When primarily screened for L-asparaginase production by Rapid plate assay using Modified M9 medium containing L-asparagine and Phenol red as indicator, 23 isolates were found to be positive by showing change in color of medium from yellow to pink. Strain V17 isolate proved to be potent producer of the enzyme with higher amount of enzyme up to 22.45 IU/ml. About 92% of the tested isolates were positive for anti-cancerous potential, indicating the Western Ghats soils as potential sources for anti-cancerous agents. Further studies on purification and characterization of enzyme are under progress.

  8. Screening and characterization of extracelluar L-asparaginase producing Bacillus subtilis strain hswx88, isolated from Taptapani hotspring of Odisha, India

    Institute of Scientific and Technical Information of China (English)

    Biswaprakash Pradhan; Sashi K Dash; Sabuj Sahoo

    2013-01-01

    Objective: To screen and isolate an eco-friendly, a thermophilic and potent L-asparaginase producing bacterium, with novel immunological properties that may obviates hypersensitivity reactions. Methods: In the present study bacterial strain isolated for extracellular L-asparaginase production from hotspring, identified by morphological, biochemical and physiological tests followed by 16S rDNA technology and the L-asparaginase production ability was tested by both semi quantitative and quantitative enzymatic assay. Result:The bacterial strain was identified as Bacillus subtilis strain hswx88 (GenBank Accession Number: JQ237656.1). The extracellular enzyme yielding capacity isolate Bacillus subtilis strain hswx88 (23.8 IU/mL) was found to be 1.7 and 14.5 times higher than the reference organism Pectobacterium carotovorum MTCC 1428 (14.2 IU/mL) and Bacillus sp. BCCS 034 (1.64 IU/mL). Conclusion: The isolate is eco-friendly and useful to produce bulk quantity of extracellular, thermophilic L-asparaginase for the treatment of various tumor cases and for preparation of acrylamide free fry food preparation.

  9. The K+ dependent asparaginase, NSE1, is crucial for plant growth and seed production in Lotus japonicus

    DEFF Research Database (Denmark)

    Credali, Alfredo; Garcia-Calderón, Margarita; Dam, Svend Secher

    2013-01-01

    The physiological role of K+-dependent and K+-independent asparaginases in plants remains unclear, and the contribution from individual isoforms during development is poorly understood. We have used reverse genetics to assess the phenotypes produced by the deficiency of K+-dependent NSE1 asparagi...

  10. Asparagine synthetase expression is linked with L-asparaginase resistance in TEL-AML1-negative but not TEL-AML1-positive pediatric acute lymphoblastic leukemia.

    Science.gov (United States)

    Stams, Wendy A G; den Boer, Monique L; Holleman, Amy; Appel, Inge M; Beverloo, H Berna; van Wering, Elisabeth R; Janka-Schaub, Gritta E; Evans, William E; Pieters, Rob

    2005-06-01

    Resistance to L-asparaginase in leukemic cells may be caused by an elevated cellular expression of asparagine synthetase (AS). Previously, we reported that high AS expression did not correlate to L-asparaginase resistance in TEL-AML1-positive B-lineage acute lymphoblastic leukemia (ALL). In the present study we confirmed this finding in TEL-AML1-positive patients (n = 28) using microarrays. In contrast, 35 L-asparaginase-resistant TEL-AML1-negative B-lineage ALL patients had a significant 3.5-fold higher AS expression than 43 sensitive patients (P < .001). Using real-time quantitative polymerase chain reaction (RTQ-PCR), this finding was confirmed in an independent group of 39 TEL-AML1-negative B-lineage ALL patients (P = .03). High expression of AS was associated with poor prognosis (4-year probability of disease-free survival [pDFS] 58% +/- 11%) compared with low expression (4-year pDFS 83% +/- 7%; P = .009). We conclude that resistance to l-asparaginase and relapse risk are associated with high expression of AS in TEL-AML1-negative but not TEL-AML1-positive B-lineage ALL.

  11. Proteins from Erwinia asparaginase Erwinase ® and E. coli asparaginase 2 MEDAC ® for treatment of human leukemia, show a multitude of modifications for which the consequences are completely unclear.

    Science.gov (United States)

    Bae, Narkhyun; Pollak, Arnold; Lubec, Gert

    2011-07-01

    L-Asparaginase from Erwinia chrysanthemi (ASPG_ERWCH; UniProtKB accession number P06608 (Erwinase(®))) and L-asparaginase 2 from Escherichia coli (ASPG2_ECOLI; UniProtKB accession number P00805 (Medac(®))), both L-asparagine amidohydrolases, are widely used for the treatment of acute lymphoblastic leukemia. A series of serious side effects have been reported and this warrants studies into the protein chemistry of the medical products sold. Mass spectrometry (MS) data on ASPG_ERWCH and ASPG2_ECOLI have not been published so far and herein a gel-based proteomics study was performed to provide information about sequence and modifications of the commercially available medical products. ASPG_ERWCH and ASPG2_ECOLI were applied onto two-dimensional gel electrophoresis, spots were in-gel digested with several proteases and resulting peptides and protein modifications were analysed by nano-ESI-LC-MS/MS. Four spots were observed for ASPG_ERWCH, six spots were observed for ASPG2_ECOLI and the identified proteins showed high sequence coverage without sequence conflicts. Several protein modifications including technical and posttranslational modifications were demonstrated. Protein modifications are known to change physicochemical, immunochemical, biological and pharmacological properties and results from this work may challenge re-designing of the product including possible removal of the modifications by the manufacturer because it is not known whether they are contributing to the serious adverse effects of the protein drug.

  12. Purification and Characterization of Glutaminase Free Asparaginase from Enterobacter cloacae: In-Vitro Evaluation of Cytotoxic Potential against Human Myeloid Leukemia HL-60 Cells.

    Directory of Open Access Journals (Sweden)

    Islam Husain

    Full Text Available Asparaginase is an important antileukemic agent extensively used worldwide but the intrinsic glutaminase activity of this enzymatic drug is responsible for serious life threatening side effects. Hence, glutaminase free asparaginase is much needed for upgradation of therapeutic index of asparaginase therapy. In the present study, glutaminase free asparaginase produced from Enterobacter cloacae was purified to apparent homogeneity. The purified enzyme was found to be homodimer of approximately 106 kDa with monomeric size of approximately 52 kDa and pI 4.5. Purified enzyme showed optimum activity between pH 7-8 and temperature 35-40°C, which is close to the internal environment of human body. Monovalent cations such as Na+ and K+ enhanced asparaginase activity whereas divalent and trivalent cations, Ca2+, Mg2+, Zn2+, Mn2+, and Fe3+ inhibited the enzyme activity. Kinetic parameters Km, Vmax and Kcat of purified enzyme were found to be 1.58×10-3 M, 2.22 IU μg-1 and 5.3 × 104 S-1, respectively. Purified enzyme showed prolonged in vitro serum (T1/2 = ~ 39 h and trypsin (T1/2 = ~ 32 min half life, which is therapeutically remarkable feature. The cytotoxic activity of enzyme was examined against a panel of human cancer cell lines, HL-60, MOLT-4, MDA-MB-231 and T47D, and highest cytotoxicity observed against HL-60 cells (IC50 ~ 3.1 IU ml-1, which was comparable to commercial asparaginase. Cell and nuclear morphological studies of HL-60 cells showed that on treatment with purified asparaginase symptoms of apoptosis were increased in dose dependent manner. Cell cycle progression analysis indicates that enzyme induces apoptosis by cell cycle arrest in G0/G1 phase. Mitochondrial membrane potential loss showed that enzyme also triggers the mitochondrial pathway of apoptosis. Furthermore, the enzyme was found to be nontoxic for human noncancerous cells FR-2 and nonhemolytic for human erythrocytes.

  13. A clinically attainable dose of L-asparaginase targets glutamine addiction in lymphoid cell lines.

    Science.gov (United States)

    Sugimoto, Koichi; Suzuki, Hiroshi I; Fujimura, Tsutomu; Ono, Asami; Kaga, Naoko; Isobe, Yasushi; Sasaki, Makoto; Taka, Hikari; Miyazono, Kohei; Komatsu, Norio

    2015-11-01

    L-asparaginase (L-ASNase) is an important branch of chemotherapy for acute lymphoblastic leukemia (ALL) and some types of non-Hodgkin's lymphoma, including natural killer (NK)-cell lymphoma. Although it mediates hydrolysis of asparagine (Asn) and glutamine (Gln), which are variably required for cancer cell survival, the relative contribution of Asn and Gln depletion to the anti-tumor activity in therapeutic doses is unclear in ALL and malignant lymphoma. Here we demonstrate that L-ASNase exerts cytotoxicity through targeting the Gln addiction phenotype in lymphoid cell lines. A clinically attainable intermediate dose of L-ASNase induced massive apoptosis in ALL Jurkat and mantle cell lymphoma Jeko cell lines, while a low dose of L-ASNase effectively killed NK-cell lymphoma cells. In the lymphoid cell lines Jurkat and Jeco, deprivation of Gln but not Asn specifically suppressed cell growth and survival, and phenocopied the action of L-ASNase. L-ASNase treatment and Gln deprivation dramatically disrupted the refilling of the tricarboxylic acid (TCA) cycle by intracellular glutamate (Glu) and disturbed the mitochondrial integrity, which were alleviated by various anaplerotic TCA cycle intermediates, suggesting a direct contribution of glutaminase activity of L-ASNase. The action of L-ASNase differs between Jurkat cells and NK-cell lymphoma cells, according to their dependence on Gln and Asn. Furthermore, we observed that high expression of glutaminase GLS1 is associated with increased sensivity to L-ASNase in pediatric B lineage ALL. Our results redefine L-ASNase as a therapeutic agent targeting Gln addiction in certain lymphoid cells and offer an additional basis for predicting L-ASNase sensitivity and engineering selective L-ASNase derivatives for leukemia and lymphoma.

  14. 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.

  15. Minimally-Myelosuppressive Asparaginase-Containing Induction Regimen for Treatment of a Jehovah’s Witness with mutant IDH1/NPM1/NRAS Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Ashkan Emadi

    2016-03-01

    Full Text Available Treatment of patients with acute myeloid leukemia (AML who do not wish to accept blood product transfusion, including Jehovah’s Witnesses, is extremely challenging. The use of conventional chemotherapy for induction of complete remission (CR results in profound anemia and thrombocytopenia requiring frequent transfusions of blood products, without which such treatment will be life-threatening. Finding a well tolerable, minimally myelosuppressive induction regimen for such patients with AML is a clear example of area of unmet medical need. Here, we report a successful treatment of a 52-year-old Jehovah’s Witness with newly diagnosed AML with peg-asparaginase, vincristine and methylprednisolone. The AML was characterized with normal karyotype, and mutations in isocitrate dehydrogenase 1 (IDH1-Arg132Ser, nucleophosmin 1 (NPM1-Trp289Cysfs*12 and neuroblastoma RAS viral oncogene homolog (NRAS-G1y12Va1. After one 28-day cycle of treatment, the patient achieved complete remission with incomplete count recovery (CRi and after the second cycle, he achieved CR with full blood count recovery. The patient has never received any blood products. Notwithstanding that myeloperoxidase-induced oxidative degradation of vincristine results in its lack of activity as monotherapy in AML, its combination with corticosteroid and asparaginase has resulted in a robust remission in this patient. Diminished steroid clearance by asparaginase activity as well as reduction in serum glutamine level induced by glutaminase enzymatic activity of asparaginase may have contributed to effective killing of the myeloblasts that carry IDH1/NPM1/NRAS mutations. In conclusion, asparaginase-containing regimens, which are approved for treatment of acute lymphoblastic leukemia (ALL but not AML, can be used to treat patients with AML who do not accept blood transfusion.

  16. PRODUCTION PURIFICATION AND CHARACTERIZATION OF EXTRACELLULAR ANTI-LEUKAEMIC L-ASPARAGINASE FROM ISOLATED BACILLUS SUBTILIS USING SOLID STATE FERMENTATION.

    Directory of Open Access Journals (Sweden)

    Susmita Shukla

    2013-08-01

    Full Text Available Bacterial L-asparaginase has been widely used as therapeutic agent in treatment of various lymphoblastic leukemia and food processing aid to reduce the formation of cancer causing acrylamide. The present work deals with production and purification of extracellular L-asparaginase from soil isolates using solid state fermentation. The isolate was characterized by big chemical test and identified as Bacillus subtilis. The enzyme production was carried out by solid state fermentation comparing the results with submerged fermentation. The enzyme was purified to near homogeneity by ammonium sulphate precipitation, dialysis, followed by gel filtration on Sephadex G-100 column, CM Sephadex C-50 and SDS-PAGE. The enzyme was purified at 110.2 folds and showed a final specific activity of 1785.7 IU/mg with 26.5% yield. SDS-PAGE of the purified enzyme revealed an apparent molecular weight of 109 kDa. The purified enzyme showed maximum activity at pH 9 when it was incubated at 50°C for 35 min. The enzyme was activated by Mg+2 and strongly inhibited by EDTA.

  17. Identification and structural analysis of an L-asparaginase enzyme from guinea pig with putative tumor cell killing properties.

    Science.gov (United States)

    Schalk, Amanda M; Nguyen, Hien-Anh; Rigouin, Coraline; Lavie, Arnon

    2014-11-28

    The initial observation that guinea pig serum kills lymphoma cells marks the serendipitous discovery of a new class of anti-cancer agents. The serum cell killing factor was shown to be an enzyme with L-asparaginase (ASNase) activity. As a direct result of this observation, several bacterial L-asparaginases were developed and are currently approved by the Food and Drug Administration for the treatment of the subset of hematological malignancies that are dependent on the extracellular pool of the amino acid asparagine. As drugs, these enzymes act to hydrolyze asparagine to aspartate, thereby starving the cancer cells of this amino acid. Prior to the work presented here, the precise identity of this guinea pig enzyme has not been reported in the peer-reviewed literature. We discovered that the guinea pig enzyme annotated as H0W0T5_CAVPO, which we refer to as gpASNase1, has the required low Km property consistent with that possessed by the cell-killing guinea pig serum enzyme. Elucidation of the ligand-free and aspartate complex gpASNase1 crystal structures allows a direct comparison with the bacterial enzymes and serves to explain the lack of L-glutaminase activity in the guinea pig enzyme. The structures were also used to generate a homology model for the human homolog hASNase1 and to help explain its vastly different kinetic properties compared with gpASNase1, despite a 70% sequence identity. Given that the bacterial enzymes frequently present immunogenic and other toxic side effects, this work suggests that gpASNase1 could be a promising alternative to these bacterial enzymes.

  18. Identification and Structural Analysis of an l-Asparaginase Enzyme from Guinea Pig with Putative Tumor Cell Killing Properties*

    Science.gov (United States)

    Schalk, Amanda M.; Nguyen, Hien-Anh; Rigouin, Coraline; Lavie, Arnon

    2014-01-01

    The initial observation that guinea pig serum kills lymphoma cells marks the serendipitous discovery of a new class of anti-cancer agents. The serum cell killing factor was shown to be an enzyme with l-asparaginase (ASNase) activity. As a direct result of this observation, several bacterial l-asparaginases were developed and are currently approved by the Food and Drug Administration for the treatment of the subset of hematological malignancies that are dependent on the extracellular pool of the amino acid asparagine. As drugs, these enzymes act to hydrolyze asparagine to aspartate, thereby starving the cancer cells of this amino acid. Prior to the work presented here, the precise identity of this guinea pig enzyme has not been reported in the peer-reviewed literature. We discovered that the guinea pig enzyme annotated as H0W0T5_CAVPO, which we refer to as gpASNase1, has the required low Km property consistent with that possessed by the cell-killing guinea pig serum enzyme. Elucidation of the ligand-free and aspartate complex gpASNase1 crystal structures allows a direct comparison with the bacterial enzymes and serves to explain the lack of l-glutaminase activity in the guinea pig enzyme. The structures were also used to generate a homology model for the human homolog hASNase1 and to help explain its vastly different kinetic properties compared with gpASNase1, despite a 70% sequence identity. Given that the bacterial enzymes frequently present immunogenic and other toxic side effects, this work suggests that gpASNase1 could be a promising alternative to these bacterial enzymes. PMID:25320094

  19. Post-treatment plasma EBV-DNA positivity predicts early relapse and poor prognosis for patients with extranodal NK/T cell lymphoma in the era of asparaginase.

    Science.gov (United States)

    Wang, Liang; Wang, Hua; Wang, Jing-hua; Xia, Zhong-jun; Lu, Yue; Huang, Hui-qiang; Jiang, Wen-qi; Zhang, Yu-jing

    2015-10-06

    Circulating Epstein-Barr virus (EBV) DNA is a biomarker of EBV-associated malignancies. Its prognostic value in early stage NK/T-cell lymphoma (NKTCL) in the era of asparaginase was investigated. 68 patients were treated with a median of 4 cycles of asparaginase-based chemotherapy followed by a median of 54.6 Gy (range 50-60 Gy) radiation. The amount of EBV-DNA was prospectively measured in both pretreatment and post-treatment plasma samples by real-time quantitative PCR. At the end of treatment, complete response (CR) rate was 79.4%, and overall response rate (ORR) was 88.2%. Patients with negative pretreatment EBV-DNA had a higher CR rate (96.0% vs. 69.8%, p = 0.023). The 3-year progression-free survival (PFS) rate and overall survival (OS) rate was 71% and 83%, respectively. In multivariate survival analysis, post-treatment EBV-DNA positivity and treatment response (non-CR) were prognostic factors for both worse PFS and OS (p EBV-DNA positivity correlated with inferior PFS and OS (both p EBV-DNA, negative post-treatment EBV-DNA correlated with better PFS and OS (both p EBV-DNA positivity can predict early relapse and poor prognosis for patients with early stage NKTCL in the era of asparaginase, and may be used as an indicator of minimal residual disease.

  20. An analytical quality by design (aQbD) approach for a L-asparaginase activity method.

    Science.gov (United States)

    Yao, Han; Vancoillie, Jochem; D'Hondt, Matthias; Wynendaele, Evelien; Bracke, Nathalie; De Spiegeleer, Bart

    2016-01-05

    L-asparaginase is an effective anti-tumor agent for acute lymphoblastic leukemia. This work presents the development of an activity determination of L-ASNase preparations for pharmaceutical quality control purposes, in accordance with analytical Quality by Design principles. Critical method attributes, the absorbance at 450 nm (A450) of the Nessler product as well as its variability, were evaluated as a function of critical method variables, by using experimental designs. The design space of the enzyme activity assay was defined (Nessler method: C(KI)/C(HgI2) of 1.90-1.95, C(NaOH)/C(HgI2) of 17.0-18.0, C(HgI2final) of 20-40 mM and time of 10-40 min; enzyme activity conditions: temperature range of 36.6-37.4 °C, pH range of the KH2PO4 buffer from 7.1 to 7.7, KH2PO4 buffer concentration: 0.18-0.22 M and L-Asn concentration of 18-22 mM), leading to a final enzyme activity assay method. A control strategy was ultimately implemented using system suitability tests.

  1. Preparation and nanoencapsulation of l-asparaginase II in chitosan-tripolyphosphate nanoparticles and in vitro release study

    Science.gov (United States)

    Bahreini, Elham; Aghaiypour, Khosrow; Abbasalipourkabir, Roghayeh; Mokarram, Ali Rezaei; Goodarzi, Mohammad Taghi; Saidijam, Massoud

    2014-07-01

    This paper describes the production, purification, and immobilization of l-asparaginase II (ASNase II) in chitosan nanoparticles (CSNPs). ASNase II is an effective antineoplastic agent, used in the acute lymphoblastic leukemia chemotherapy. Cloned ASNase II gene ( ansB) in pAED4 plasmid was transformed into Escherichia coli BL21pLysS (DE3) competent cells and expressed under optimal conditions. The lyophilized enzyme was loaded into CSNPs by ionotropic gelation method. In order to get optimal entrapment efficiency, CSNP preparation, chitosan/tripolyphosphate (CS/TPP) ratio, and protein loading were investigated. ASNase II loading into CSNPs was confirmed by Fourier transform infrared (FTIR) spectroscopy, and morphological observation was carried out by transmission electron microscopy. Three absolute CS/TPP ratios were studied. Entrapment efficiency and loading capacity increased with increasing CS and TPP concentration. The best ratio was applied for obtaining optimal ASNase II-loaded CSNPs with the highest entrapment efficiency. Size, zeta potential, entrapment efficiency, and loading capacity of the optimal ASNase II-CSNPs were 340 ± 12 nm, 21.2 ± 3 mV, 76.2% and 47.6%, respectively. The immobilized enzyme showed an increased in vitro half-life in comparison with the free enzyme. The pH and thermostability of the immobilized enzyme was comparable with the free enzyme. This study leads to a better understanding of how to prepare CSNPs, how to achieve high encapsulation efficiency for a high molecular weight protein, and how to prolong the release of protein from CSNPs. A conceptual understanding of biological responses to ASNase II-loaded CSNPs is needed for the development of novel methods of drug delivery.

  2. Statistical and evolutionary optimization for enhanced production of an antileukemic enzyme, L-asparaginase, in a protease-deficient Bacillus aryabhattai ITBHU02 isolated from the soil contaminated with hospital waste.

    Science.gov (United States)

    Singh, Yogendra; Srivastav, S K

    2013-04-01

    Over the past few decades, L-asparaginase has emerged as an excellent anti-neoplastic agent. In present study, a new strain ITBHU02, isolated from soil site near degrading hospital waste, was investigated for the production of extracellular L-asparaginase. Further, it was renamed as Bacillus aryabhattai ITBHU02 based on its phenotypical features, biochemical characteristics, fatty acid methyl ester (FAME) profile and phylogenetic similarity of 16S rDNA sequences. The strain was found protease-deficient and its optimal growth occurred at 37 degrees C and pH 7.5. The strain was capable of producing enzyme L-asparaginase with maximum specific activity of 3.02 +/- 0.3 Umg(-1) protein, when grown in un-optimized medium composition and physical parameters. In order to improve the production of L-asparaginase by the isolate, response surface methodology (RSM) and genetic algorithm (GA) based techniques were implemented. The data achieved through the statistical design matrix were used for regression analysis and analysis of variance studies. Furthermore, GA was implemented utilizing polynomial regression equation as a fitness function. Maximum average L-asparaginase productivity of 6.35 Umg(-1) was found at GA optimized concentrations of 4.07, 0.82, 4.91, and 5.2 gL(-1) for KH2PO4, MgSO4 x 7H2O, L-asparagine, and glucose respectively. The GA optimized yield of the enzyme was 7.8% higher in comparison to the yield obtained through RSM based optimization.

  3. Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis was successfully treated by centrifuge/membrane hybrid double-filtration plasmapheresis.

    Science.gov (United States)

    Wang, Taina; Xu, Bin; Fan, Rong; Liu, Zhihong; Gong, Dehua

    2016-01-01

    Asparaginase-associated concurrence of hyperlipidemia, hyperglobulinemia, and thrombocytosis is a rare complication requiring aggressive lipoprotein apheresis, but no one of currently available lipoprotein apheresis methods can simultaneously resolve the 3 abnormalities. Herein, we reported a construction of double-filtration plasmapheresis (DFPP) using a combination of centrifugal/membranous plasma separation techniques to successfully treat a patient with hyperlipidemia, hyperglobulinemia, and thrombocytosis. A male presented with severe hyperlipidemia, hyperglobulinemia, and thrombocytosis during asparaginase treatment for NK/T-cell lymphoblastic lymphoma and was scheduled to receive lipoprotein apheresis. To simultaneously remove lipoproteins, immunoglobulin, and deplete platelets from blood, a centrifuge/membrane hybrid DFPP was constructed as following steps: plasma and part of platelets were separated first from whole blood by centrifugal technique and then divided by a fraction plasma separator into 2 parts: platelets and plasma components with large size, which were discarded; and those containing albumin, which were returned to blood with a supplement of extrinsic albumin solution. DFPP lasted 240 minutes uneventfully, processing 5450-mL plasma. The concentrations of plasma components before DFPP were as follows: triglycerides 38.22 mmol/L, total cholesterols 22.98 mmol/L, immunoglobulin A (IgA) 15.7 g/L, IgG 12.7 g/L, and IgM 14.3 g/L; whereas after treatment were 5.69 mmol/L, 2.38 mmol/L, 2.5 g/L, 7.7 g/L, and 0.4 g/L, respectively. The respective reduction ratio was 85.1%, 89.6%, 83.9%, 39.4%, and 96.9%. Platelet count decreased by 40.4% (from 612 × 10(9)/L to 365 × 10(9)/L). Centrifuge/membrane hybrid DFPP can simultaneously remove lipoproteins, immunoglobulin, and deplete platelets, with a success in treatment of asparaginase treatment-induced hyperlipidemia, hyperglobulinemia, and thrombocytosis, and may be useful for patients

  4. 门冬酰胺酶相关儿童急性胰腺炎诊治研究进展%Progress of diagnosis and treatment of asparaginase associated pancreatitis in children

    Institute of Scientific and Technical Information of China (English)

    石苇

    2016-01-01

    门冬酰胺酶(ASP)是儿童急性淋巴细胞白血病和非霍奇金淋巴瘤联合化疗方案中的关键药物之一.ASP相关急性胰腺炎(AAP)是ASP的主要严重不良反应.现通过复习有关儿童AAP的近年国内外文献和我国《培门冬酶治疗急性淋巴细胞白血病和恶性淋巴瘤的专家共识》,以及对网络收集的历年来我国儿童AAP报道资料进行归纳与统计分析,参照国际AAP诊断标准,提出儿童AAP流行病学、临床表现、早期诊断和有效治疗要点,以及左旋门冬酰胺酶和培门冬酶的AAP临床对比.全文资料数据详尽,分析归纳依据充分,相关经验的临床可操作性强,对临床有效诊治儿童AAP具有较大的参考价值.%Asparaginase(ASP) is an important drug in the treatment of childhood acute lymphoblastic leukemia and non-Hodgkin lymphoma.Asparaginase associated pancreatitis (AAP) is the main treatment-adverse events of asparaginase.After reviewing the recent foreign literatures about AAP and the Chinese expert about polyethylene glycol conjugated asparaginase (PEG-ASP) in the treatment of acute lymphoblastic leukemia and malignant lymphoma with asparaginase,conclude and analysis the data about childhood AAP and show the epidemiology,clinical features,early diagnosis and effective treatment of children with AAP.Make clinical compare of L-asparaginase and PEG-ASP.Based on the full grasp of the relevant data,analyzing,introducing and integrating,this may be helpful to the diagnosis and treatment of childhood AAP.

  5. Clinical diagnosis and treatment of asparaginase associated pancreatitis in adults%成人门冬酶相关胰腺炎的临床诊治

    Institute of Scientific and Technical Information of China (English)

    李梦洁; 何牧卿; 沈益民

    2015-01-01

    目的 探讨成人门冬酶相关胰腺炎(AAP)的临床特点及诊治过程,旨在提高AAP诊治水平.方法 回顾性分析2009年1月至2015年6月间浙江医院血液内科及温州医科大学附属第二医院血液科收治的384例急性淋巴细胞白血病(ALL)患者的临床资料,所有患者均给予含培门冬酶或左旋门冬酰胺酶(L-asp)的多药联合化疗,分析AAP的发生情况、临床表现、诊断、治疗及转归.结果 384例ALL患者中18例发生AAP,发生率为4.7%,其中轻症AAP (MAAP) 13例,重症AAP(SAAP)5例.16例AAP发生在诱导化疗期,2例发生在维持强化期.腹痛为主要临床表现,血淀粉酶及脂肪酶活性均升高.治疗后,MAAP患者的腹痛症状缓解,血淀粉酶及脂肪酶活性明显下降,继续使用培门冬酶或L-asp化疗,未见胰腺炎复发.5例SAAP患者血淀粉酶及脂肪酶反复升高,其中1例因合并重症感染及囊肿破裂出血而病死.结论 成人ALL患者在门冬酶化疗期间出现腹痛症状应考虑AAP可能,加强血淀粉酶及脂肪酶检测,辅以B超和CT检查有助于早期诊治AAP,并改善患者预后.%Objective To investigate the clinical characteristics and the course of diagnosis and therapy of asparaginase associated pancreatitis (AAP) in adults, in order to improve the ability of diagnosis and treatment.Methods Data of 384 cases of acute lymphoblastic leukemia (ALL) who received treatment in Department of Hematology, Zhejiang Hospital, and Department of Hematology, Second Hospital Affiliated to Wenzhou Medical University from January 2009 to June 2015 was retrospectively analyzed.All patients were given multi-drug chemotherapy including PEG-asparaginase or L-asparaginase, the incidence of AAP, clinical manifestations, diagnosis, treatment and prognosis were analyzed.Results Among the 384 cases, 18 patients developed AAP, and the incidence of AAP was 4.7%, including 13 cases of mild AAP (MAAP), 5 cases of severe AAP (SAAP).Sixteen cases of

  6. Clinical Utility of Ammonia Concentration as a Diagnostic Test in Monitoring of the Treatment with L-Asparaginase in Children with Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Małgorzata Czogała

    2014-01-01

    Full Text Available L-asparaginase (ASP is an enzyme used as one of the basic regimens in the acute lymphoblastic leukemia (ALL therapy. Because of the possibility of the enzyme inactivation by antibodies, monitoring of ASP activity is essential. The aim of the study was to examine if plasma concentration of ammonia, a direct product of the reaction catalyzed by ASP, can be used in the assessment of ASP activity. A group of 87 patients with acute lymphoblastic leukemia treated in the Department of Pediatric Oncology and Hematology in Krakow was enrolled to the study. ASP activity and ammonia concentration were measured after ASP administrations during induction. A positive correlation was found between the ammonia concentration and ASP activity (R=0.44; P<0.0001 and between the medium values of ammonia concentration and ASP activity (R=0.56; P<0.0001. The analysis of ROC curves revealed the moderate accuracy of the ammonia concentration values in the ASP activity assessment. It was also found that the medium value of ammonia concentrations can be useful in identification of the patients with low (<100 IU/L and undetectable (<30 IU/L ASP activity. The plasma ammonia concentration may reflect ASP activity and can be useful when a direct measurement of the activity is unavailable.

  7. Microchip CE-LIF method for the hydrolysis of L-glutamine by using L-asparaginase enzyme reactor based on gold nanoparticle.

    Science.gov (United States)

    Qiao, Juan; Qi, Li; Yan, Huijuan; Li, Yaping; Mu, Xiaoyu

    2013-02-01

    L-Asparaginase (L-Asnase) can suppress the growth of malignant cells by rapid depletion of two essential amino acids, L-glutamine (L-Gln) and L-asparagine (L-Asn). To study the cytotoxic effect and the secondary complications of L-Asnase in the treatment of acute lymphoblastic leukemia, the development of a novel enzyme reactor of L-Asnase for the hydrolysis of L-Gln, employing the enzyme-gold nanoparticle conjugates in capillary, was reported in this work. First, a microchip CE (MCE)-LIF was established for the separation of L-amino acids (L-Gln and L-glutamic acid) and studying the hydrolysis of L-Gln by using L-Asnase enzyme reactor. Then, using L-Gln as target analyte, the enzyme kinetics of L-Asnase in free solution, enzyme-gold nanoparticle conjugates (E-GNP), and the enzyme-gold nanoparticle conjugates immobilized in capillary (E-GNP-C) were investigated in detail with the proposed MCE-LIF method. Moreover, for optimizing the enzymatic reaction efficiency, three important parameters, including the length of capillary, the enzyme concentration reacted with gold nanoparticle and the amount of L-Asnase immobilized on the gold nanoparticle, have been studied. Owing to the high specific activity, the E-GNP-C enzyme reactor exhibited the best performance for the hydrolysis of L-Gln.

  8. Cerebral venous thrombosis in adult patients with acute lymphoblastic leukemia or lymphoblastic lymphoma during induction chemotherapy with l-asparaginase: The GRAALL experience.

    Science.gov (United States)

    Couturier, Marie-Anne; Huguet, Françoise; Chevallier, Patrice; Suarez, Felipe; Thomas, Xavier; Escoffre-Barbe, Martine; Cacheux, Victoria; Pignon, Jean-Michel; Bonmati, Caroline; Sanhes, Laurence; Bories, Pierre; Daguindau, Etienne; Dorvaux, Véronique; Reman, Oumedaly; Frayfer, Jamile; Orvain, Corentin; Lhéritier, Véronique; Ifrah, Norbert; Dombret, Hervé; Hunault-Berger, Mathilde; Tanguy-Schmidt, Aline

    2015-11-01

    Central nervous system (CNS) thrombotic events are a well-known complication of acute lymphoblastic leukemia (ALL) induction therapy, especially with treatments including l-asparaginase (l-ASP). Data on risk factors and clinical evolution is still lacking in adult patients. We report on the clinical evolution of 22 CNS venous thrombosis cases occurring in 708 adults treated for ALL or lymphoblastic lymphoma (LL) with the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-induction protocol, which included eight L-ASP (6,000 IU/m(2) ) infusions. The prevalence of CNS thrombosis was 3.1%. CNS thrombosis occurred after a median of 18 days (range: 11-31) when patients had received a median of three l-ASP injections (range: 2-7). Patients with CNS thrombosis exhibited a median antithrombin (AT) nadir of 47.5% (range: 36-67%) at Day 17 (range: D3-D28), and 95% of them exhibited AT levels lower than 60%. There were no evident increase in hereditary thrombotic risk factors prevalence, and thrombosis occurred despite heparin prophylaxis which was performed in 90% of patients. Acquired AT deficiency was frequently detected in patients with l-ASP-based therapy, and patients with CNS thrombosis received AT prophylaxis (45%) less frequently than patients without CNS thrombosis (83%), P = 0.0002). CNS thrombosis was lethal in 5% of patients, while 20% had persistent sequelae. One patient received all planned l-ASP infusions without recurrence of CNS thrombotic whereas l-ASP injections were discontinued in 20 patients during the management of thrombosis without a significant impact on overall survival (P = 0.4).

  9. Biochemical characterization and immobilization of Erwinia carotovoral-asparaginase in a microplate for high-throughput biosensing of l-asparagine.

    Science.gov (United States)

    Labrou, Nikolaos E; Muharram, Magdy Mohamed

    2016-10-01

    l-Asparaginases (l-ASNase, E.C. 3.5.1.1) catalyze the conversion of l-asparagine to l-aspartic acid and ammonia. In the present work, a new form of l-ASNase from a strain of Erwinia carotovora (EcaL-ASNase) was cloned, expressed in Escherichia coli as a soluble protein and characterized. The enzyme was purified to homogeneity by a single-step procedure comprising ion-exchange chromatography. The properties of the recombinant enzyme were investigated employing kinetic analysis and molecular modelling and the kinetic parameters (Km, kcat) were determined for a number of substrates. The enzyme was used to assemble a microplate-based biosensor that was used for the development of a simple assay for the determination of l-asparagine in biological samples. In this sensor, the enzyme was immobilized by crosslinking with glutaraldehyde and deposited into the well of a microplate in 96-well format. The sensing scheme was based on the colorimetric measurement of ammonia formation using the Nessler's reagent. This format is ideal for micro-volume applications and allows the use of the proposed biosensor in high-throughput applications for monitoring l-asparagine levels in serum and foods samples. Calibration curve was obtained for l-asparagine, with useful concentration range 10-200μΜ. The biosensor had a detection limit of 10μM for l-asparagine. The method's reproducibility was in the order of ±3-6% and l-asparagine mean recoveries were 101.5%.

  10. Sensitivity to L-asparaginase is not associated with expression levels of asparagine synthetase in t(12;21)+ pediatric ALL.

    Science.gov (United States)

    Stams, Wendy A G; den Boer, Monique L; Beverloo, H Berna; Meijerink, Jules P P; Stigter, Rolinda L; van Wering, Elisabeth R; Janka-Schaub, Gritta E; Slater, Rosalyn; Pieters, Rob

    2003-04-01

    The (12;21) translocation resulting in TEL/AML1 gene fusion is present in about 25% of childhood precursor B-lineage acute lymphoblastic leukemia (ALL) and is associated with a good prognosis and a high cellular sensitivity to L-asparaginase (L-Asp). ALL cells are thought to be sensitive to L-Asp due to lower asparagine synthetase (AS) levels. Resistance to L-Asp may be caused by an elevated cellular level of AS or by the ability of resistant cells to rapidly induce the expression of the AS gene on L-Asp exposure. AS may be a target regulated by t(12;21). We studied the relationship between t(12;21) and the mRNA level of AS to investigate a possible mechanism underlying L-Asp sensitivity. Real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis surprisingly revealed that 30 patients positive for t(12;21) expressed 5-fold more AS mRNA compared with 17 patients negative for t(12;21) (P =.008) and 11 samples from healthy controls (P =.016). The mRNA levels of AS between t(12;21)(-) ALL and healthy controls did not differ. No difference was found between ALL patients positive or negative for t(12;21) in the capacity to up-regulate AS after in vitro L-Asp exposure, excluding a defective capacity for t(12;21) cells in up-regulating AS on L-Asp exposure. Moreover, no correlation was observed between AS mRNA expression and sensitivity to L-Asp. We conclude that the sensitivity of t(12;21)(+) childhood ALL to L-Asp is not associated with the expression level of the AS gene. Furthermore, we contradict the general thought that leukemic cells specifically lack AS compared with normal bone marrow and blood cells.

  11. Comparison of three rapamycin dosing schedules in A/J Tsc2+/- mice and improved survival with angiogenesis inhibitor or asparaginase treatment in mice with subcutaneous tuberous sclerosis related tumors

    Directory of Open Access Journals (Sweden)

    Dabora Sandra L

    2010-02-01

    Full Text Available Abstract Background Tuberous Sclerosis Complex (TSC is an autosomal dominant tumor disorder characterized by the growth of hamartomas in various organs including the kidney, brain, skin, lungs, and heart. Rapamycin has been shown to reduce the size of kidney angiomyolipomas associated with TSC; however, tumor regression is incomplete and kidney angiomyolipomas regrow after cessation of treatment. Mouse models of TSC2 related tumors are useful for evaluating new approaches to drug therapy for TSC. Methods In cohorts of Tsc2+/- mice, we compared kidney cystadenoma severity in A/J and C57BL/6 mouse strains at both 9 and 12 months of age. We also investigated age related kidney tumor progression and compared three different rapamycin treatment schedules in cohorts of A/J Tsc2+/- mice. In addition, we used nude mice bearing Tsc2-/- subcutaneous tumors to evaluate the therapeutic utility of sunitinib, bevacizumab, vincristine, and asparaginase. Results TSC related kidney disease severity is 5-10 fold higher in A/J Tsc2+/- mice compared with C57BL/6 Tsc2+/- mice. Similar to kidney angiomyolipomas associated with TSC, the severity of kidney cystadenomas increases with age in A/J Tsc2+/- mice. When rapamycin dosing schedules were compared in A/J Tsc2+/- cohorts, we observed a 66% reduction in kidney tumor burden in mice treated daily for 4 weeks, an 82% reduction in mice treated daily for 4 weeks followed by weekly for 8 weeks, and an 81% reduction in mice treated weekly for 12 weeks. In the Tsc2-/- subcutaneous tumor mouse model, vincristine is not effective, but angiogenesis inhibitors (sunitinib and bevacizumab and asparaginase are effective as single agents. However, these drugs are not as effective as rapamycin in that they increased median survival only by 24-27%, while rapamycin increased median survival by 173%. Conclusions Our results indicate that the A/J Tsc2+/- mouse model is an improved, higher through-put mouse model for future TSC

  12. Pharmacokinetics of Recombinant E.coli L-asparaginase in Rats%重组E.coli L-天冬酰胺酶在大鼠中的药物代谢动力学

    Institute of Scientific and Technical Information of China (English)

    陈建华; 吴梧桐; 平野和行

    2002-01-01

    应用放射性核素示踪技术研究125I重组E.coli L-天冬酰胺酶在大鼠体内的药物代谢动力学.125I重组L-天冬酰胺酶静脉注射后24h内,在尿,粪,胆汁中的排泄量分别占注射剂量的68.95%,4.44%和5.36%.测定血浆中125I重组E.coli L-天冬酰胺酶浓度,应用聚丙烯酰胺凝胶电泳和生物成像分析系统结合方法评价原药水平,由房室模型评价药物动力学参数,静注后,浓度时间曲线符合二房室模型.初期和末端的t1/2分别为0.52~0.63 h和2.39~2.76h.AUC与剂量成正比.重组E.coli L-天冬酰胺酶的分解代谢产物主要随尿液排泄,重组E.coli L-天冬酰胺酶在大鼠中的药物动力学参数为临床试验提供了有用依据.%The distribution of 125[ recombinant E. coli L-asparaginase in tissues or organs and the excretion in urine,feces and bile were studied with in vivo radioactive tracer technique. The amount of radioactivity excreted in urine, feces and bile within 24 h after intravenous administration of125I recombinant E.col L- asparaginase to rats was 68.95%,4.44%and 5.36% of the dose respectively. 125I recombinant E. coli L- asparaginase in plasma samples was determined. The levels of structural intact molecule in plasma samples were evaluated by SDS-PAGE and bio-imnging analyzer system.Pharmacokinetic parameters were assessed with a model-dependent method. The concentration-time curves of recombinant with the two-compartment model. The first and terminal elimination t1/2 were 0.52 ~ 0.63 h and 2.39 ~ 2.76 h respectively.AUC was linearly related to the doses. The results of distribution in tissues or organs and excretion in urine suggested that the metabolites of the enzyme were cleared by mechanisms of urinary excretion. Pharmacokinetics parameters of recombinant E . coli L- asparaginase in rats are warranted for the design of future clinical trials.

  13. Produção biotecnológica de L-asparaginase(ASP3) de Saccharomyces cerevisiae em sistema de expressão heterólogo Pichia pastoris

    OpenAIRE

    Rafaela Coelho Correia

    2015-01-01

    A leucemia linfóide aguda (LLA) é considerada uma doença grave dos glóbulos brancos, sendo mais comum e mais agressiva em crianças e adolescentes. O tratamento para a LLA tem avançado devido aos estudos para a otimização de drogas já utilizadas em quimioterapias. Entre essas drogas estão as enzimas L- asparaginases (ASPases) que atuam reduzindo a concentração de L-asparagina (Asn) na corrente sanguínea, impedindo a proliferação das células cancerosas, visto que essas não conseguem sintetizar ...

  14. Utility of baseline, interim and end-of-treatment 18F-FDG PET/CT in extranodal natural killer/T-cell lymphoma patients treated with L-asparaginase/pegaspargase

    Science.gov (United States)

    Chang, Yu; Fu, Xiaorui; Sun, Zhenchang; Xie, Xinli; Wang, Ruihua; Li, Zhaoming; Zhang, Xudong; Sheng, Guangyao; Zhang, Mingzhi

    2017-01-01

    Positron emission tomography-computed tomography (PET/CT) is widely used for initial staging and monitoring treatment responses in Hodgkin and diffuse large B-cell lymphoma. However, its prognostic value in extranodal natural killer (NK)/T-cell lymphoma (ENKL) remains unclear. Here, we conducted a retrospective study to determine the impact of PET/CT in ENKL. Fifty-two patients newly diagnosed with ENKL were enrolled. Baseline maximum standardized uptake values (SUVmax), whole-body metabolic tumor volume (WBMTV) and whole-body total lesion glycolysis (WBTLG) were recorded. Additionally, interim PET/CT (I-PET) and end-of-treatment PET/CT (E-PET) results were scored using a 5-point scale. Patients were divided into groups using baseline parameter cut-off values; significant differences were found in overall survival (OS) and progression-free survival (PFS) between the high and low WBMTV and WBTLG groups and in OS between the two SUVmax groups. Positive I-PET and E-PET results predicted inferior PFS and OS. A multivariate analysis showed that baseline WBTLG, I-PET and E-PET results were associated with PFS and OS, and baseline SUVmax was an independent predictor of OS. Thus, baseline WBTLG, I-PET and E-PET results are good predictors of PFS and OS in ENKL patients who received L-asparaginase/pegaspargase in their first-line treatment, and baseline SUVmax is a valuable tool for assessing OS. PMID:28117395

  15. Safety considerations in children:L-asparaginase-induced adverse drug reactions%左旋门冬酰胺酶不良反应引起的儿童用药安全性问题

    Institute of Scientific and Technical Information of China (English)

    黄琳; 刘一; 任晓蕾; 李玉珍

    2011-01-01

    Objective: To investigate the characteristics of adverse drug reaction (ADR) in children caused by L-asparaginase (L-ASP) from clinical practice, and to provide reference for rational use of drugs. Methods: Two cases of pediatric asthma induced by multiple doses of L-ASP were reported. Literature about L-ASP-in-duced ADR reported in domestic pharmaceutical journals from 1979 to 2011 was collected and analyzed statistically. Safety issues of L-ASP in children were further considered based on its structure, administration routes, dosing interval, and action mechanisms. Results: ADR caused by L-ASP in children was common. The main type was allergic reaction, and followed by digestive system damage and blood abnormalities. A small number of children had acute hemorrhagic necrotizing pancreatitis and severe ADR in nervous system, which had poor prognosis. Conclusion : More attention should be paid to children to avoid and reduce the occurrence of ADR induced by L-ASP.%目的:以临床实例出发探讨左旋门冬酰胺酶不良反应在儿童的发生特点,为临床用药安全提供依据.方法:报道反复使用左旋门冬酰胺酶致儿童过敏性哮喘2例,并检索1979-2011年国内医药期刊公开报道的左旋门冬酰胺酶致不良反应的病例,从药物结构、给药方式、给药时间间隔以及药物作用机制等方面进一步论述左旋门冬酰胺酶在儿童用药的安全性问题.结果:左旋门冬酰胺酶不良反应较常见,其不良反应以过敏反应为主,其次为消化系统损害和血液系统异常,且少数急性出血坏死性胰腺炎、重度神经系统不良反应患儿预后极差.结论:临床应重视左旋门冬酰胺酶的用药安全问题,积极采取措施防范不良反应的发生.

  16. Analysis of L-asparaginase induced elevation of blood ammonia and hepatic encephalopathy%应用左旋门冬酰胺酶致血氨升高和肝性脑病发生的原因分析

    Institute of Scientific and Technical Information of China (English)

    李渊; 任汉云; 岑溪南; 尹玥; 梁赜隐

    2013-01-01

    目的 总结左旋门冬酰胺酶(L-Asp)临床应用中各种不良反应的发生率以及对3例患者引起肝性脑病的原因进行分析.方法 收集2009年12月至2010年12月收治的有完整资料的23例患者,在L-Asp应用前、中、后检测血氨水平、转氨酶、血清白蛋白及凝血功能.结果 ①23例患者均出现血氨升高,血氨开始升高的中位时间为用药第2天,到达最高值的中位时间为用药第4天,血氨最高值中位数为300(194~446) μmol/L,在中位停药后5(3~7)d恢复至正常水平.其中3例(13.0%)发生肝性脑病.②23例患者均出现血浆纤维蛋白原(FIB)降低,其中仅FIB降低的10例(43.5%),伴APTT延长的13例(56.5%);FIB水平的最低值均在用药1周后出现,14例(60.9%)血浆FIB轻度降低(1~2 g/L),9例(39.1%)血浆FIB显著降低(0~1 g/L).③6例(26.1%)出现转氨酶轻度升高(<2倍正常值),8例(34.8%)出现低白蛋白血症.结论 L-Asp应用过程中血氨水平均升高,应密切监测血氨水平,警惕肝性脑病的发生,尤其是中老年患者、既往有肝脏疾病患者或长期大量饮酒者.L-Asp亦可引起低纤维蛋白血症、低白蛋白血症及转氨酶异常,需监测凝血功能及肝功能,必要时需输注血浆及护肝治疗.%Objective To summarize the incidence of various adverse reactions in the clinical application of L-asparaginase (L-Asp),and to analyze the cause of hepatic encephalopathy in three cases.Methods The complete data of 23 patients in our department from December 2009 to December 2010 were collected.Their blood ammonia levels,transaminase,serum albumin and blood coagulation function before,during and after the L-Asp application were assayed.Results ① All patients had elevated blood ammonia level after the L-Asp application.This occurred 2 days after the beginning of treatment and the median time to reach peak level (ranged from 194 to 446 μmol/L,with a median value of 300 μmol/L) was 4 days

  17. ALL患儿L-Asp治疗相关性血浆氨基酸水平变化及其意义%Contents of L-Asparaginase-Related Amino Acids in the Plasma of Children with ALL

    Institute of Scientific and Technical Information of China (English)

    江华; 顾龙君; 陈静; 潘慈; 薛惠良

    2003-01-01

    Objective To detect the contents of L-asparaginase(L-Asp)-related amino acids in ALL children receiving L-Asp treatment; and to study the relationship between changes in L-Asp contents and clinical efficacy on ALL. Methods Plasma concentrations of asparagine (Asn), aspartic acid (Aspa), glutamine (Gln) and glutamic acid (Glu) in different stages of L-Asp treatment were measured by the HPLC-FLD method in 20 children with ALL (17 cases of B-ALL and 3 of T-ALL). Results The plasma Asn level after the 1st administration of L-Asp decreased significantly. With the administration of L-Asp according to the induction remission formula of All-XH99, the Asn level remained low, even to nil level. This status remained for 7 days after cessation of L-Asp, and even 10 days in 15 cases of B-ALL, but the Asn level in all the cases of T-ALL and only 2 cases of B-ALL increased and even returned to nomal 7 days after L-Asp treatment ended. The concentration of Glu after the second and the last administrations of L-Asp increased significantly and it returned to normal on the 7th day after cessation of L-Asp, while the concentration of Aspa increased and failed to return to normal on day 10 after cessation of of L-Asp. The concentration of Gln slightly decreased during the course of treatment with L-Asp, but the difference was not significant compared with that before treatment. Conclusions The Asn level of children with T-ALL after cessation of L-Asp recovers earier than that of children with B-ALL, indicating that it may be helpful for individualization of L-Asp administration in the treatment of ALL on the basis of the immunophenotype of children. The glutaminase activity of L-Asp does not exert effects on the treatment.%目的检测ALL患儿血浆左旋门冬酰胺酶(L-Asp)治疗过程中相关氨基酸水平变化,探讨这种变化与临床疗效的相关性,为L-Asp的个体化用药提供依据.方法通过HPLC-FLD技术检测20例初治ALL患儿(17例为B-ALL,3例为T-ALL)在L

  18. 重组L-天门冬酰胺酶II的液相色谱/电喷雾离子化质谱法分析%HIGH PERFORMANCE LIQUID CHROMATOGRAPHY / ELECTROSPRAY IONIZATON MASS SPECTROMETRIC CHARACTERIZATION OF RECOMBINANT L-ASPARAGINASE II

    Institute of Scientific and Technical Information of China (English)

    韩俊; 盛龙生; 杨仲元; 相秉仁; 安登魁

    2001-01-01

    AIM To characterize the primary structure of recombinant L-asparaginase II product. METHODS The molecular weight of the protein was measured by pneumatically-assisted electrospray ionization mass spectrometry with flow injection mode. Subsequently, tryptic peptide mapping was performed by high performance liquid chromatography on a C8 column with tandem UV and MS detection. An easy-to-use and simple denaturation process with trichloroacetic acid was conducted prior to tryptic digest so as to release the digest resistance from the protein structure. The amino acid sequences of the tryptic peptides were elucidated based on their in-source collision-induced dissociation spectra. RESULTS The measured molecular mass was different from the theoretical value. Three amino acid variations were unambiguously detected along the peptide backbone derived from the gene-encoding sequence. CONCLUSION This paper revealed that LC/ESI/MS had provided a promising and robust technique in primary structure analysis and quality control of DNA-derived recombinant protein pharmaceuticals.%目的 对基因重组L-天门冬酰胺酶II产品进行一级结构分析。方法 采用流动注射方式,电喷雾离子化质谱法测定分子量;三氯乙酸变性,胰蛋白酶水解后,HPLC测定肽图谱;结合质谱源内碰撞诱导解离技术,解析酶解肽段的氨基酸顺序。结果 分子量测定值与理论值不符,质谱解析表明样品中存在3个氨基酸变异现象,由此计算的分子量与测定值吻合。结论 液相色谱/电喷雾质谱法为基因重组蛋白质药物的一级结构分析和质量控制提供了新途径。

  19. 左旋门冬酰胺酶与盐霉素联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖凋亡的影响%Effects of salinomycin combined with L-asparaginase on proliferation and apoptosis of human acute T-cell leukemia Jurkat cells

    Institute of Scientific and Technical Information of China (English)

    朱锦灿; 陈小宇; 刘成成; 祝爱珍; 刘革修; 曾慧兰

    2013-01-01

    目的:研究左旋门冬酰胺酶(L-asparaginase,L-ASP)与盐霉素(salinomycin,Sal)联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖和凋亡的影响及其机制.方法:CCK-8试剂盒检测细胞增殖情况;Western blotting方法检测凋亡相关蛋白Bcl-2、caspase-3、caspase-8、caspase-9及细胞色素C表达的变化;流式细胞术分析各实验组细胞凋亡率之间的差别.结果:不同浓度的L-ASP和Sal单独处理Jurkat细胞株后均显示出明显的增殖抑制作用,L-ASP的IC50为8.12 IU/L,Sal 的IC50为0.75 μmol/L.而两药联合使用的增殖抑制作用更显著(P<0.05);合用指数计算公式结果显示两药为协同作用.Western blotting 显示联合用药组与L-Asp、Sal单独处理组相比,Bcl-2蛋白表达明显减少,caspase-3、caspase-8、caspase-9和胞浆细胞色素C水平明显增高;干预48 h后行流式细胞术检测结果显示L-ASP(2.5 IU/L)单独处理组和Sal(0.5μmol/L)单独处理组细胞凋亡率分别为(7.11±0.23)%和(25.43±0.47)%,与对照组(6.67±0.13)%比较差别有统计学意义(P<0.05),联合用药组细胞凋亡率(39.12±1.97)%分别与L-ASP、Sal单独处理组比较,差别有统计学意义(P<0.05).结论:左旋门冬氨酸酶与盐霉素联合作用于Jurkat细胞具有协同抑制增殖和诱导凋亡的作用.

  20. Pharmacodynamic sof L-Asparaginase in Childhood Acute Leukemia

    NARCIS (Netherlands)

    I.M. Appel (Inge)

    2008-01-01

    textabstractThe 'Three Princes of Serendip' is an old Persian fairytale about three men who were on a mission and encountered things that looked irrelevant at first sight but which turned out to be important later on. They discovered things by serendipity and sagacity. Serendip is the Persian name f

  1. Propriedades da asparaginase e determinação de compostos nitrogenados em algumas especies do genero Crotalaria

    OpenAIRE

    Angela Pierre Vitoria

    1994-01-01

    Resumo: O aminoácido asparagina (ASN) é um dos principais compostos nitrogenados transportado pelos vasos condutores das plantas, principalmente nas leguminosas. O nitrogênio (N) que constitui este aminoácido é reutilizado nos órgãos em formação da planta (órgãos dreno) para a síntese de proteínas e compostos nitrogenados em geral. No entanto, existe a necessidade de metabolização da ASN para que este N apresentese na forma livre e portanto possa ser reutilizado. São conhecidas duas enzimas c...

  2. EST Table: AV404106 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available aa pdb|2ZAK|A Chain A, Orthorhombic Crystal Structure Of Precursor E. Coli Isoaspartyl PeptidaseL-Asparaginase (Ecaiii) With Active...r E. Coli Isoaspartyl PeptidaseL-Asparaginase (Ecaiii) With Active- Site T179a Mu...tation pdb|3C17|A Chain A, Hexagonal Crystal Structure Of Precursor E. Coli Isoaspartyl PeptidaseL-Asparaginase (Ecaiii) With Active.... Coli Isoaspartyl PeptidaseL-Asparaginase (Ecaiii) With Active- Site T179a Mutat

  3. Drug: D02997 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available gs in Japan [BR:br08301] 4 Agents affecting cellular function 42 Antineoplastics 429 Miscellaneous 4291 Othe...tic agents L01XX02 Asparaginase D02997 L-Asparaginase (JAN); Asparaginase (USAN) Antineoplastics [BR:br08308

  4. NCBI nr-aa BLAST: CBRC-CFAM-03-0021 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CFAM-03-0021 ref|ZP_01580220.1| L-asparaginases, type II [Delftia acidovorans ...SPH-1] gb|EAV75159.1| L-asparaginases, type II [Delftia acidovorans SPH-1] ZP_01580220.1 2.1 32% ...

  5. Pharmacokinetics and bioequivalence of self-assembly nanocapsules loaded with asparaginase%载天冬酰胺酶自组装纳米囊的药动学及生物等效性

    Institute of Scientific and Technical Information of China (English)

    谢江川; 胡雪原; 晏子俊; 周云莉; 张景勍

    2016-01-01

    目的 研究载天冬酰胺酶(Asp)自组装透明质酸-聚乙二醇(HA-g-PEG)/二甲基-β环糊精(DCD)纳米囊(AHDPs)在雄性SD大鼠体内的药代动力学和生物等效性.方法 考察了AHDPs的透射电镜、粒径、zeta电位、包封率,并分别测定大鼠静脉给予AHDPs和游离Asp后,不同时间点大鼠血浆样品中Asp的活性.采用DAS 2.1.1软件计算药动学参数,对AHDPs和游离Asp进行生物等效性评价.结果 AHDPs的平均粒径为(439.63±8.49) nm,zeta电位为(-20.43±2.20) mV,平均包封率为(55.75±4.11)%(n=3).AHDPs和游离Asp的主要药动学参数AUC0-48h分别为(138.93±0.89)U· mL-1·h和(46.38±1.98) U· mL-1·h,AUC0-∞分别为(175.22±13.59)U·mL-1·h和(51.44±3.01)U·mL-1·h,t1/2分别为(4.46±1.04)h和(1.86±0.38)h.与游离Asp比较,AHDPs的AUC0-48 h、AUC0-∞和t1/2分别提高至约游离ASP的3.00、3.40和2.40倍.AUC0-48 h、AUC0-∞和Cmax的90%置信区间分别为76.9%~78.3%、76.9%~78.3%、92.8%~94.4%.结论 AHDPs延长了Asp在大鼠体内的生物半衰期,提高了Asp在大鼠体内的生物利用度,且AHDPs与游离Asp不具有生物等效性.

  6. Contribution of Asparagine Catabolism to Salmonella Virulence.

    Science.gov (United States)

    McLaughlin, Patrick A; McClelland, Michael; Yang, Hee-Jeong; Porwollik, Steffen; Bogomolnaya, Lydia; Chen, Juei-Suei; Andrews-Polymenis, Helene; van der Velden, Adrianus W M

    2017-02-01

    Salmonellae are pathogenic bacteria that cause significant morbidity and mortality in humans worldwide. Salmonellae establish infection and avoid clearance by the immune system by mechanisms that are not well understood. We previously showed that l-asparaginase II produced by Salmonella enterica serovar Typhimurium (S Typhimurium) inhibits T cell responses and mediates virulence. In addition, we previously showed that asparagine deprivation such as that mediated by l-asparaginase II of S Typhimurium causes suppression of activation-induced T cell metabolic reprogramming. Here, we report that STM3997, which encodes a homolog of disulfide bond protein A (dsbA) of Escherichia coli, is required for l-asparaginase II stability and function. Furthermore, we report that l-asparaginase II localizes primarily to the periplasm and acts together with l-asparaginase I to provide S Typhimurium the ability to catabolize asparagine and assimilate nitrogen. Importantly, we determined that, in a murine model of infection, S Typhimurium lacking both l-asparaginase I and II genes competes poorly with wild-type S Typhimurium for colonization of target tissues. Collectively, these results indicate that asparagine catabolism contributes to S Typhimurium virulence, providing new insights into the competition for nutrients at the host-pathogen interface.

  7. Role of γ-glutamyltranspeptidase in the pathogenesis of Helicobacter pylori infection.

    Science.gov (United States)

    Rimbara, Emiko; Mori, Shigetarou; Kim, Hyun; Shibayama, Keigo

    2013-10-01

    γ-Glutamyltranspeptidase and asparaginase have been shown to play important roles in Helicobacter pylori colonization and cell death induced by H. pylori infection. In this study, the association of γ-glutamyltranspeptidase and asparaginase was elucidated by comparing activities of both deamidases in H. pylori strains from patients with chronic gastritis, gastric and duodenal ulcers, and gastric cancer. γ-Glutamyltranspeptidase activities in H. pylori strains from patients with gastric cancer were significantly higher than in those from patients with chronic gastritis or gastric ulcers. There was a wide range of asparaginase activities in H. pylori strains from patients with gastric cancer and these were not significantly than those from patients with other diseases. To identify the contributions of γ-glutamyltranspeptidase and asparaginase to gastric cell inflammation, human gastric epithelial cells (AGS line) were infected with H. pylori wild-type and knockout strains and inflammatory responses evaluated by induction of interleukin-8 (IL-8). IL-8 response was significantly decreased by knockout of the γ-glutamyltranspeptidase-encoding gene but not by knockout of the asparaginase-encoding gene. Additionally, IL-8 induction by infection with the H. pylori wild-type strain was significantly decreased by adding glutamine during infection. These findings indicate that IL-8 induction caused by γ-glutamyltranspeptidase activity in H. pylori is mainly attributable to depletion of glutamine. These data suggest that γ-glutamyltranspeptidase plays a significant role in the chronic inflammation caused by H. pylori infection.

  8. 抗体夹心酶联免疫吸附法测定重组E.coli L-天冬酰胺酶及药代动力学研究%Antibody sandwich enzyme-linked immunoadsorbent assay for determination of recombinant E.coli L-asparaginase in rat plasma and its pharmacokinetics

    Institute of Scientific and Technical Information of China (English)

    陈建华; 吴梧桐; 平野和行

    2003-01-01

    目的建立大鼠血浆中重组E.coli L-天冬酰胺酶的抗体夹心酶联免疫吸附测定法,并进行药代动力学研究.方法应用重组E.coli L-天冬酰胺酶免疫家兔,分离IgG,用DEAE-纤维素柱色谱纯化,辣根过氧化物酶标记抗体,建立抗体夹心酶联免疫吸附法,测定大鼠血浆中重组E.coli L-天冬酰胺酶浓度.结果方法的线性范围为1~64 U*L-1,血药浓度与时间的关系符合二房室模型,初期和末端的T1/2分别为0.50~0.57 h和2.45~3.02 h,AUC与剂量成正比.结论建立的抗体夹心酶联免疫吸附法在灵敏度、特异性、线性范围、精密度和回收率等方面,满足药代动力学研究要求.实验方法和重组E.coli L-天冬酰胺酶在大鼠中的药代动力学参数为临床研究提供了手段和依据.

  9. Comparison of the Anti-Leukemia Effect and Mechanism of L-Asparaginase between Two Different Strains%两种菌种来源的左旋门冬酰胺酶抗白血病作用与机制比较

    Institute of Scientific and Technical Information of China (English)

    王开美; 徐宏贵; 郭海霞; 金少文; 罗湘琴; 方建培

    2014-01-01

    比较大肠杆菌来源的左旋门冬酰胺酶(E coli-L-Asp)与欧文菌来源的左旋门冬酰胺酶(Erwinia-L-Asp)体外抗白血病作用,并探讨其作用机制.以两种来源的L-Asp分别处理急性淋巴细胞白血病(ALL)细胞株(REH、Jurkat),采用CCK-8试剂盒检测细胞增殖变化(IC50),Annexin V/PI双染流式细胞术检测细胞凋亡,高压液相色谱(HPLC)检测用药后培养液中4种氨基酸[门冬酰胺(Asn)、门冬氨酸(Aspa)、谷氨酰胺(G1n)、谷氨酸(G1u)]浓度的变化.结果表明,REH、Jurkat细胞株对两种L-Asp的抑制作用均敏感,且在一定时间内存在明显剂量效应关系,即在较低的药物浓度下,细胞增殖抑制率处于较低水平,而药物浓度增加后,细胞的增殖抑制率明显升高,其中作用后24 h,Erwinia-L-Asp组细胞抑制率、细胞凋亡率均明显高于E coli-L-Asp组(P<0.05),但至48 h两组比较差异无显著性(P>0.05).两种药物在低浓度时均能耗竭培养液中的Asn,且作用相当(P>0.05),高浓度时耗竭Gin作用才凸显,而Erwinia-L-Asp的作用明显强于E.coli-L-Asp(P<0.05).结论:两种菌种来源的L-Asp抗白血病作用与剂量存在量效关系,除耗竭外环境中的Asn和Gin外,诱导细胞凋亡也是其抗白血病作用之一.Erwinia-L-Asp具有起效快、Gin耗竭作用较强的特点,可作为临床儿童ALL治疗的一线药物选择.

  10. Kinetics of inclusion body formation and its correlation with the characteristics of protein aggregates in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Arun K Upadhyay

    Full Text Available The objective of the research was to understand the structural determinants governing protein aggregation into inclusion bodies during expression of recombinant proteins in Escherichia coli. Recombinant human growth hormone (hGH and asparaginase were expressed as inclusion bodies in E.coli and the kinetics of aggregate formation was analyzed in details. Asparaginase inclusion bodies were of smaller size (200 nm and the size of the aggregates did not increase with induction time. In contrast, the seeding and growth behavior of hGH inclusion bodies were found to be sequential, kinetically stable and the aggregate size increased from 200 to 800 nm with induction time. Human growth hormone inclusion bodies showed higher resistance to denaturants and proteinase K degradation in comparison to those of asparaginase inclusion bodies. Asparaginase inclusion bodies were completely solubilized at 2-3 M urea concentration and could be refolded into active protein, whereas 7 M urea was required for complete solubilization of hGH inclusion bodies. Both hGH and asparaginase inclusion bodies showed binding with amyloid specific dyes. In spite of its low β-sheet content, binding with dyes was more prominent in case of hGH inclusion bodies than that of asparaginase. Arrangements of protein molecules present in the surface as well as in the core of inclusion bodies were similar. Hydrophobic interactions between partially folded amphiphillic and hydrophobic alpha-helices were found to be one of the main determinants of hGH inclusion body formation. Aggregation behavior of the protein molecules decides the nature and properties of inclusion bodies.

  11. Kinetics of inclusion body formation and its correlation with the characteristics of protein aggregates in Escherichia coli.

    Science.gov (United States)

    Upadhyay, Arun K; Murmu, Aruna; Singh, Anupam; Panda, Amulya K

    2012-01-01

    The objective of the research was to understand the structural determinants governing protein aggregation into inclusion bodies during expression of recombinant proteins in Escherichia coli. Recombinant human growth hormone (hGH) and asparaginase were expressed as inclusion bodies in E.coli and the kinetics of aggregate formation was analyzed in details. Asparaginase inclusion bodies were of smaller size (200 nm) and the size of the aggregates did not increase with induction time. In contrast, the seeding and growth behavior of hGH inclusion bodies were found to be sequential, kinetically stable and the aggregate size increased from 200 to 800 nm with induction time. Human growth hormone inclusion bodies showed higher resistance to denaturants and proteinase K degradation in comparison to those of asparaginase inclusion bodies. Asparaginase inclusion bodies were completely solubilized at 2-3 M urea concentration and could be refolded into active protein, whereas 7 M urea was required for complete solubilization of hGH inclusion bodies. Both hGH and asparaginase inclusion bodies showed binding with amyloid specific dyes. In spite of its low β-sheet content, binding with dyes was more prominent in case of hGH inclusion bodies than that of asparaginase. Arrangements of protein molecules present in the surface as well as in the core of inclusion bodies were similar. Hydrophobic interactions between partially folded amphiphillic and hydrophobic alpha-helices were found to be one of the main determinants of hGH inclusion body formation. Aggregation behavior of the protein molecules decides the nature and properties of inclusion bodies.

  12. Annual Research Progress Report Fiscal Year 1990. Volume 2. Department of Clinical Investigation (Brooke Army Medical Center)

    Science.gov (United States)

    1990-10-01

    W7-r5 CON AdI -f-O AT NUMBEf’l(’q CHARLES P. KINGSLEY Major, MC i 9. PERFORMING ORGANIZATION NlAME ANO ADDRESS 10 PROGRAM rLEmN . PROJECT. TASK...efficacy, toxicity and feasibility of administration of PEG -L-asparaginase versus native L-asparaginase as part of a standard combination chemotherapy...describe the pharmacokinetics and cytotoxic effect within the cerebrospi- nal fluid (CSF) of intravenous 6-mercaptopurine (6-MP) given -as a single agent

  13. Partial purification and characterization of an enzyme involved in the formation of beta-aspartyl dipeptides in rat kidney.

    Science.gov (United States)

    Tanaka, T; Hirai, M; Nakajima, T

    1978-11-01

    The formation of beta-aspartyl-glycine from asparagine and glycine was demonstrated in the supernatant of rat kidney. The enzyme involved in this process was partially purified. Based on the properties of the enzyme reaction and the coincidence of purification rates of this activity and asparaginase, it can be speculated that the enzyme is a kind of asparaginase. Examination of the preference for beta-aspartyl donors and acceptors showed that asparagine and glycine were the preferred donor and acceptor, respectively. beta-Aspartyl dipeptides also transferred their aspartyl residues to amino acids. Amino acids other than glycine also accepted the aspartyl moiety from the donors.

  14. Stabilization of Proteins by Polymer Conjugation via ATRP

    Science.gov (United States)

    2008-08-31

    organophosphate hydrolase Organophosphorous hydrolase (OPH) that was sheathed in poly(2-ethylhexyl methacrylate-co-MPEG-methacrylate) was soluble in...applied to organophosphorous hydrolase. The enzyme was sheathed in copolymer matrix and dissolved in dichloromethane solution of poly(methyl methacrylate...lysozyme, asparaginase, organophosphorous hydrolase etc., by ATRP and by conventional pegylation. In vitro mouse and human serum stability study was

  15. Endoscopic Cystogastrostomy: Minimally Invasive Approach for Pancreatic Pseudocyst

    Directory of Open Access Journals (Sweden)

    Gull-Zareen Khan Sial

    2014-12-01

    Full Text Available Pancreatic pseudocysts in children are not uncommon. Non-resolving pseudocysts often require surgical intervention. Endoscopic cystogastrostomy is a minimally invasive procedure which is recommended for this condition. We report a large pancreatic pseudocyst in a 4-year old child, which developed following therapy with PEG-Asparaginase for acute lymphoblastic leukemia. It was managed with minimally invasive procedure.

  16. Endoscopic cystogastrostomy: minimally invasive approach for pancreatic pseudocyst.

    Science.gov (United States)

    Sial, Gull-Zareen Khan; Qazi, Abid Quddus; Yusuf, Mohammed Aasim

    2015-01-01

    Pancreatic pseudocysts in children are not uncommon. Non-resolving pseudocysts often require surgical intervention. Endoscopic cystogastrostomy is a minimally invasive procedure which is recommended for this condition. We report a large pancreatic pseudocyst in a 4-year old child, which developed following therapy with PEG-Asparaginase for acute lymphoblastic leukemia. It was managed with minimally invasive procedure.

  17. 21 CFR 610.53 - Dating periods for licensed biological products.

    Science.gov (United States)

    2010-04-01

    .... Albumin (Human) 3 years ......do (a) 5 years. ......do ......do (b) 3 years, provided labeling recommends...) Polyvalent ......do ......do 5 years with an initial 10 percent excess of potency, provided labeling... initial 10 percent excess of potency. Antivenin (Micurus fulvius) ......do ......do Do. Asparaginase...

  18. Construction of Potent Recombinant Strain Through Intergeneric Protoplast Fusion in Endophytic Fungi for Anticancerous Enzymes Production Using Rice Straw.

    Science.gov (United States)

    El-Gendy, Mervat Morsy Abbas Ahmed; Al-Zahrani, Salha Hassan Mastour; El-Bondkly, Ahmed Mohamed Ahmed

    2017-02-15

    Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.

  19. Patented Techniques for Acrylamide Mitigation in High-Temperature Processed Foods

    DEFF Research Database (Denmark)

    Mariotti, Salome; Pedreschi, Franco; Antonio Carrasco, José

    2011-01-01

    .g. time and temperature of cooking) which inhibits Maillard Reaction; (ii) Reducing acrylamide precursor levels in raw materials to be cooked at high temperatures (e.g. by using microor-ganisms, asparaginase, amino acids and saccharides, blanching, etc.). In this paper, most of the recent patents...

  20. Combination chemotherapy for marrow relapse in children and adolescents with acute lymphocytic leukaemia.

    Science.gov (United States)

    Amadori, S; Spiriti, M A; Meloni, G; Pacilli, L; Papa, G; Mandelli, F

    1981-04-01

    38 children with acute lymphocytic leukaemia (ALL) in haematologic relapse were retreated with vincristine, daunomycin and prednisone (VPD) together with intrathecal methotrexate and prednisone, followed by asparaginase in those patients not in complete remission after 4 weeks. The overall complete remission (CR) rate was 79%; asparaginase was needed to achieve CR in 7 of the 30 responding patients. The median duration of second remission was only 36 weeks, but 6 out of 15 children receiving the COAP-POMP-CART consolidation regimen remain in continuous second remission after 37-260 weeks; 3 of them are currently off all therapy. It is concluded that a prolonged second remission can be achieved in children with ALL in bone marrow relapse by combining intensive chemotherapy with the prevention of meningeal leukaemia.

  1. Cell-penetrating peptides meditated encapsulation of protein therapeutics into intact red blood cells and its application.

    Science.gov (United States)

    He, Huining; Ye, Junxiao; Wang, Yinsong; Liu, Quan; Chung, Hee Sun; Kwon, Young Min; Shin, Meong Cheol; Lee, Kyuri; Yang, Victor C

    2014-02-28

    Red blood cells (RBCs) based drug carrier appears to be the most appealing for protein drugs due to their unmatched biocompatability, biodegradability, and long lifespan in the circulation. Numerous methods for encapsulating protein drugs into RBCs were developed, however, most of them induce partial disruption of the cell membrane, resulting in irreversible alterations in both physical and chemical properties of RBCs. Herein, we introduce a novel method for encapsulating proteins into intact RBCs, which was meditated by a cell penetrating peptide (CPP) developed in our lab-low molecular weight protamine (LMWP). l-asparaginase, one of the primary drugs used in treatment of acute lymphoblastic leukemia (ALL), was chosen as a model protein to illustrate the encapsulation into erythrocytes mediated by CPPs. In addition current treatment of ALL using different l-asparaginase delivery and encapsulation methods as well as their associated problems were also reviewed.

  2. GenBank blastx search result: AK243329 [KOME

    Lifescience Database Archive (English)

    Full Text Available N13 in linkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to S...LC1A4 and SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel

  3. GenBank blastx search result: AK243597 [KOME

    Lifescience Database Archive (English)

    Full Text Available N13 in linkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to S...LC1A4 and SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel

  4. GenBank blastx search result: AK061969 [KOME

    Lifescience Database Archive (English)

    Full Text Available inkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to SLC1A4 an...d SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel a

  5. GenBank blastx search result: AK242961 [KOME

    Lifescience Database Archive (English)

    Full Text Available N13 in linkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to S...LC1A4 and SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel

  6. GenBank blastx search result: AK104362 [KOME

    Lifescience Database Archive (English)

    Full Text Available inkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to SLC1A4 an...d SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel a

  7. GenBank blastx search result: AK111986 [KOME

    Lifescience Database Archive (English)

    Full Text Available inkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to SLC1A4 an...d SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel a

  8. GenBank blastx search result: AK112031 [KOME

    Lifescience Database Archive (English)

    Full Text Available inkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to SLC1A4 an...d SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel a

  9. GenBank blastx search result: AK060839 [KOME

    Lifescience Database Archive (English)

    Full Text Available inkage group 13 Contains part of two novel genes, a novel gene for a protein similar to asparaginases, a novel... gene similar to RAB1B (RAS oncogene family member 1B), a novel gene, two novel genes similar to SLC1A4 an...d SLC1A1 (solute carrier family 1 members 4 and 1) and ORF1 and ORF2 of a novel a

  10. PCR detection of ansA from marine bacteria and its sequence characteristics from Bacillus tequilensis NIOS4.

    Science.gov (United States)

    Nayak, Sagar; Porob, Seema; Fernandes, Areena; Meena, Ram Murti; Ramaiah, Nagappa

    2014-02-01

    As many as 71 marine bacterial DNA extracts were PCR screened for L-asparaginase (ansA), a key gene in anti-cancer molecular-searches. Over 62% (44) of them were positive for ansA gene. The positive cultures were from genera Bacillus and Staphylococcus. The ansA gene cloned from isolate NIOS4 belonging to recently described Bacillus tequilensis is 1099 bp in length with a 990 bp ORF coding for 329 amino acids. BLASTx analysis revealed this sequence to be 98% similar to earlier reported ansA sequence from B. subtilis (Accession no. NP390239.1). By comparing its deduced amino acid sequence with other bacterial asparaginase sequences six substitutions at positions 305(Thr), 313(Lys), 314(Leu), 315(Asp), 318(Arg), and 320(Gln) are observed. Key residues like Thr(12), Thr(85), Asp(86), Lys(156), and Phe(165) taking part in active-site formation and imparting catalytic properties are conserved. The phylogenetic tree based of the ansA amino acid sequences revealed close relatedness of the NIOS4 ansA sequence with B. subtilis (Accession no. NP 390239.1). It's very close genetic resemblance to B. subtilis and conservation of certain key amino acid residues suggest it as a prospective candidate for evaluation and, production of L-asparaginases.

  11. Complete blood count using VCS (volume, conductivity, light scatter) technology is affected by hyperlipidemia in a child with acute leukemia.

    Science.gov (United States)

    Gokcebay, D G; Azik, F M; Isik, P; Bozkaya, I O; Kara, A; Tavil, E B; Yarali, N; Tunc, B

    2011-12-01

    Asparaginase, an effective drug in the treatment of childhood acute lymphoblastic leukemia (ALL), has become an important component of most childhood ALL regimens during the remission induction or intensification phases of treatment. The incidence range of asparaginase-associated lipid abnormalities that are seen in children is 67-72%. Lipemia causes erroneous results, which uses photometric methods to analyze blood samples. We describe a case of l-asparaginase-associated severe hyperlipidemia with complete blood count abnormalities. Complete blood count analysis was performed with Beckman COULTER(®) GEN·S™ system, which uses the Coulter Volume, Conductivity, Scatter technology to probe hydrodynamically focused cells. Although an expected significant inaccuracy in hemoglobin determination occurred starting from a lipid value of 3450 mg/dl, we observed that triglyceride level was 1466 mg/dl. Complete blood count analysis revealed that exceptionally high hemoglobin, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration levels vs. discordant with red blood cell count, mean corpuscular volume, and hematocrit levels. Total leukocyte count altered spontaneously in a wide range, and was checked with blood smear. Platelet count was in expected range (Table 1). Thus, we thought it was a laboratory error, and the patient's follow-up especially for red cell parameters was made by red blood cell and hematocrit values.

  12. A trombosis story and PRES.

    Science.gov (United States)

    Kartal, Vural; Zara, Zeynep; Yilmaz, Sema; Ayhan, Aylin; Yoruk, Asim; Timur, Cetin

    2014-01-01

    Trombosis is seen in children with acute lymphoblastic leukemia during or after L-asparaginase treatment. Posterior reversible encephalopathy syndrome (PRES) is a complex syndrome characterized with sudden hypertension, headache, nausea, vomiting, alteration in the state of consciousness, vision defect and seizures. The cases related to this syndrome have been reportedly seen after eclampsia, organ transplantation, immunsuppressive treatments, autoimmune diseases and chemotherapy. Vasogenic edema occuring in the brain parencyhma constitues the basic pathophysiology. We present a case who developed seizures during treatment for B-cell acute lymphoblastic leukemia and diagnosed as posterior reversible encephalopathy.

  13. Occurrence of Streptomyces aurantiacus in Mangroves of Bhitarkanika

    Directory of Open Access Journals (Sweden)

    Gupta, N.

    2007-01-01

    Full Text Available Thirteen strains of Streptomyces were isolated from phyllosphere of nine mangrove tree species found in Bhitarkanika mangrove ecosystem of Orissa. According to physiological, biochemical data, all 13 of the isolates were taxonomically identified to the genus Streptomyces as aurantiacus species. All strains are grayish, spirals and forming amorphous colony. Almost all utilized araginose, produced H2S, resistant towards rifampicin and penicillin, urea except few strains. However, they exhibited different extracellular activity like phosphate solubilization, lipase and L asparaginase production. This is a unique report from this mangrove ecosystem as far as Streptomyces occurrence is concerned.

  14. Acute kidney injury and bilateral symmetrical enlargement of the kidneys as first presentation of B-cell lymphoblastic lymphoma.

    Science.gov (United States)

    Shi, Su-fang; Zhou, Fu-de; Zou, Wan-zhong; Wang, Hai-yan

    2012-12-01

    Lymphoblastic lymphoma is an uncommon subtype of lymphoid neoplasm in adults. Acute kidney injury at initial presentation due to lymphoblastic lymphoma infiltration of the kidneys has rarely been described. We report a 19-year-old woman who presented with acute kidney injury due to massive lymphomatous infiltration of the kidneys. The diagnosis of B-cell lymphoblastic lymphoma was established by immunohistochemical study of the biopsied kidney. The patient had an excellent response to the VDCLP protocol (vincristine, daunomycin, cyclophosphamide, asparaginase, and dexamethasone) with sustained remission. We recommend that lymphomatous infiltration be considered in patients presenting with unexplained acute kidney injury and enlarged kidneys.

  15. Acute Myeloid Leukaemia | EU Clinical Trials Register [EU Clinical Trials Register

    Lifescience Database Archive (English)

    Full Text Available inical trial with GRASPA, Red Blood cells encapsulating L-Asparaginase, in patients affected by Acute Myeloi...ndition or disease under investigation E.1.1Medical condition(s) being investigated Acute...ion E.1.2Version 14.1 E.1.2Level LLT E.1.2Classification code 10000886 E.1.2Term Acute...old and less than 85 years old- Newly diagnosed Acute Myeloid Leukemia (AML) or post myelodysplastic syndrom

  16. Treatment of adult acute lymphoblastic leukaemia.

    Science.gov (United States)

    Jacobs, P; Wood, L; Novitzky, N

    1990-01-01

    Eighty-five consecutive patients with acute lymphoblastic leukaemia (ALL), having a median age of 24 years (range 10-69 years), underwent induction and consolidation chemotherapy with weekly parenteral vincristine, Adriamycin, l-asparaginase and daily oral prednisone (VAAP), followed by standard (CNS) prophylaxis. Maintenance therapy was given for 3 years and consisted of daily 6-mercaptopurine, weekly methotrexate and monthly intrathecal therapy, with drug intensification comprising either vincristine, Adriamycin and l-asparaginase (VAA) or cyclophosphamide, vincristine, cytosine arabinoside and prednisone (COAP). Complete remission (CR) was obtained in 59 patients (69%) and only the French-American-British (FAB) L1 morphology was a significant predictive factor (P = 0.048). Twenty-three patients failed to achieve CR and of these 12 had primary drug resistance. Median follow-up is currently 260 weeks, median predicted survival of all patients is 58 weeks and for those who achieved CR it is 104 weeks. Median duration of CR is 70 weeks. Of the prognostic factors for survival, only FAB L1 subtype was significant. Bone marrow relapses occurred in 29 patients, and of these 9 (31%) achieved CR. There has been CNS relapse in two patients and both have died. Eleven patients continue in CR off therapy, with a median of 152 weeks. This regimen is effective, with acceptable toxicity, and a number of patients are potentially cured. The incidence of resistant and relapsing disease is an argument for further intensifying both induction and postinduction therapy.

  17. Transport and metabolic effects of alpha-aminoisobutyric acid in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kim, K W; Roon, R J

    1982-11-24

    alpha-Aminoisobutyric acid is actively transported into yeast cells by the general amino acid transport system. The system exhibits a Km for alpha-aminoisobutyric acid of 270 microM, a Vmax of 24 nmol/min per mg cells (dry weight), and a pH optimum of 4.1-4.3. alpha-Aminoisobutyric acid is also transported by a minor system(s) with a Vmax of 1.7 nmol/min per mg cells. Transport occurs against a concentration gradient with the concentration ratio reaching over 1000:1 (in/out). The alpha-aminoisobutyric acid is not significantly metabolized or incorporated into protein after an 18 h incubation. alpha-Aminoisobutyric acid inhibits cell growth when a poor nitrogen source such as proline is provided but not with good nitrogen sources such as NH+4. During nitrogen starvation alpha-aminoisobutyric acid strongly inhibits the synthesis of the nitrogen catabolite repression sensitive enzyme, asparaginase II. Studies with a mutant yeast strain (GDH-CR) suggest that alpha-aminoisobutyric acid inhibition of asparaginase II synthesis occurs because alpha-aminoisobutyric acid is an effective inhibitor of protein synthesis in nitrogen starved cells.

  18. Analysis of the efficacy and safety of a combined gemcitabine, oxaliplatin and pegaspargase regimen for NK/T-cell lymphoma

    Science.gov (United States)

    Xia, Zhong-jun; Huang, Hui-qiang; Jiang, Wen-qi; Lu, Yue

    2016-01-01

    Extranodal natural killer/T-cell lymphoma (ENKTL) is an aggressive neoplasm with a poor outcome. Novel L-asparaginase-based treatment regimens, such as GELOX (gemcitabine, oxaliplatin, and L-asparaginase) and P-gemox (gemcitabine, oxaliplatin, and pegaspargase), have shown promising results against stage IE/IIE ENKTL. To define the general applicability of P-gemox, in a retrospective analysis we examined the efficacy and safety of P-gemox in a cohort of 117 patients with newly diagnosed or relapsed/refractory ENKTL. Treatment included 2 to 8 cycles of P-gemox: intravenous gemcitabine (1250 mg/m2) and oxaliplatin (85 mg/m2) and intramuscular pegaspargase (2500 IU/m2) on day 1 and repeated every 2 weeks, or intravenous gemcitabine (1000 mg/m2) on days 1 and 8 and intravenous oxaliplatin (130 mg/m2) and intramuscular pegaspargase (2500 IU/m2) on day 1 and repeated every 3 weeks. Upon completion of treatment, the overall response rate was 88.8%, and responses were similar for newly diagnosed and relapsed/refractory patients. After a median follow-up of 17 months, the 3-year overall and progression-free survival rates were 72.7% and 57.8%, respectively. Multivariate analysis showed that CR after treatment was the most significant factor affecting survival. P-gemox thus appears to be an effective and well-tolerated treatment for patients with ENKTL. PMID:27072578

  19. [Recombinant cephalosporin-acid synthesase: optimisation of expression in E.coli cells, immobilisation and application for biocatalytic cefazolin synthesis].

    Science.gov (United States)

    Eldarov, M A; Sklyarenko, A V; Dumina, M V; Medvedeva, N V; Jgoun, A A; Satarova, J E; Sidorenko, A I; Emperian, A S; Yarotsky, S V

    2015-01-01

    Cephalosporin acid synthetase (CASA) is responsible for specific to synthesis of cephalosporin-acids, its expression in Escherichia coli cells is accompanied by accumulation of unprocessed insoluble precursor. In order to optimize conditions of recombinant CASA production we have studied the effects of several parameters of strain cultivation, including growth media composition, temperature, and inoculation dose. Also plasmids for production of CASA variants with the signal sequence of Erwinia carotovora L-asparaginase (ansCASA) and "leaderless" CASA were created in search of more efficient expression constructs. Removal of the N-terminal secretion signal sequence reduced the production of functionally active CASA more than 10-fold and inhibited strain growth. Insertion of the L-asparaginase signal sequence increased the specific enzyme activity in the resultant recombinant strain. The ansCASA producing strain was used to develop the method of immobilization of the recombinant enzyme on an epoxy-activated macroporous acrylic support. The resultant biocatalyst performed effective synthesis of cefazolin from 3-[(5-methyl-1,3,4-thiadiazol-2-il)-thiomethyl]-7- aminocephalosporanic acid (MMTD-7-ACA) and methyl ester of 1(H)-tetrazolilacetic acid (МETzAA), under mild conditions a transformation level of MMTD-7-ACA to cefazolin of 95% is reached.

  20. Thrombotic complications in children with non-Hodgkin lymphoma

    Directory of Open Access Journals (Sweden)

    N. V. Lipay

    2014-07-01

    Full Text Available Our study was aimed at identifying of risk factors of venous thrombosis (VT in children with non-Hodgkin lymphomas. VT episodes were registered in 13 of 174 children treated (7.5 %. Possible impact of morphological type, initial mediastinal involvement, gender, age and use of L-asparaginase as a risk factor of thrombosis development were analyzed. Using multivariate analysis primary mediastinal tumor (OR = 4.73 [CI: 1.42–17.10] and patient age older than 13 years (OR = 4.3 [CI: 1.19–20.28 were identified as prognostic factors of thrombosis development (р < 0,05.

  1. Thrombotic complications in children with non-Hodgkin lymphoma

    Directory of Open Access Journals (Sweden)

    N. V. Lipay

    2013-01-01

    Full Text Available Our study was aimed at identifying of risk factors of venous thrombosis (VT in children with non-Hodgkin lymphomas. VT episodes were registered in 13 of 174 children treated (7.5 %. Possible impact of morphological type, initial mediastinal involvement, gender, age and use of L-asparaginase as a risk factor of thrombosis development were analyzed. Using multivariate analysis primary mediastinal tumor (OR = 4.73 [CI: 1.42–17.10] and patient age older than 13 years (OR = 4.3 [CI: 1.19–20.28 were identified as prognostic factors of thrombosis development (р < 0,05.

  2. Consensus definitions of 14 severe acute toxic effects for childhood lymphoblastic leukaemia treatment

    DEFF Research Database (Denmark)

    Schmiegelow, Kjeld; Attarbaschi, Andishe; Barzilai, Shlomit

    2016-01-01

    Although there are high survival rates for children with acute lymphoblastic leukaemia, their outcome is often counterbalanced by the burden of toxic effects. This is because reported frequencies vary widely across studies, partly because of diverse definitions of toxic effects. Using the Delphi...... method, 15 international childhood acute lymphoblastic leukaemia study groups assessed acute lymphoblastic leukaemia protocols to address toxic effects that were to be considered by the Ponte di Legno working group. 14 acute toxic effects (hypersensitivity to asparaginase, hyperlipidaemia, osteonecrosis......, thromboembolism, and Pneumocystis jirovecii pneumonia) that are serious but too rare to be addressed comprehensively within any single group, or are deemed to need consensus definitions for reliable incidence comparisons, were selected for assessment. Our results showed that none of the protocols addressed all 14...

  3. Chemo-sensitivity in a panel of B-cell precursor acute lymphoblastic leukemia cell lines, YCUB series, derived from children.

    Science.gov (United States)

    Goto, Hiroaki; Naruto, Takuya; Tanoshima, Reo; Kato, Hiromi; Yokosuka, Tomoko; Yanagimachi, Masakatsu; Fujii, Hisaki; Yokota, Shumpei; Komine, Hiromi

    2009-10-01

    Sensitivity to 10 anticancer drugs was evaluated in 6 childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL) cell lines. Authenticity of newly established cell lines was confirmed by genomic fingerprinting. The line YCUB-5R established at relapse was more resistant to 4-hydroperoxy-cyclophosphamide, cytarabine, L-asparaginase, topotecan, fludarabine, and etoposide than YCUB-5 from the same patient at diagnosis. Of the drugs tested, etoposide and SN-38 (irinotecan) showed highest efficacy in the panel, with 50% growth inhibition at 0.22-1.8 microg/ml and 0.57-3.6 ng/ml, respectively. This cell line panel offers an in vitro model for the development of new therapies for childhood BCP-ALL.

  4. Computational approach for enzymes present in Capsicum annuum: A review

    Directory of Open Access Journals (Sweden)

    Shivendu Ranjan

    2013-12-01

    Full Text Available Capasicum annuumor sweet bell pepper is one of the more economical and agriculturally viable vegetable grown all over the world owing to its antioxidant and other medicinal properties. This review highlights the essential enzymes present and its mode of action using bioinformatics online tools viz.uniprot, swissprot and Brenda enzyme db and ExPAsy protein databases. The enzymes viz. peroxidase, polyphenol oxidase, tyrosinase, catecholase, Pectin esterase, Catalase, 9-lipoxygenase, L-asparaginase, Polygalactouronase, Capsanthin and Ribulose-Phosphate 3-Epimerase contribute to its properties by various molecular mechanisms. Understanding of these mechanisms will be helpful for application of these enzymes in food processing and in the production of food ingredients. The increasing sophistication of processing industries creates a demand for abroad variety of enzymes with characteristics compatible with food processing conditions for e.g. shelf life of fruits and vegetables canbe increased by decreasing the levels of peroxidase and polyphenoloxidase

  5. A study of intermittent alternating drug program reinduction therapy on the frequency and duration of response in adult acute leukemia.

    Science.gov (United States)

    McCredie, K B; Freireich, E J; Bodey, G P; Burgess, M A; Whitecar, J P; Smith, T L

    1976-01-01

    Of 41 adults with a diagnosis of acute leukemia that were randomized for induction therapy in combination with methotrexate, 6-MP, vincristine and prednisone (POMP) versus a combination of cytosine arabinoside, cytoxan, vincristine and prednisone (COAP), 23 (56%) patients achieved a complete remission. During remission, patients received consolidation therapy with the three courses of remission induction regimen that they had not received initially. They then received daunomycin (three courses) and L-asparaginase and were then maintained for two years with their induction therapy. The median duration of survival for all patients was 40 weeks; the median duration of survival of those patients that responded to chemotherapy was 80 weeks. There was no significant difference between the two induction regimens with regard to complete remission more than four and one half years from diagnosis and two and one half years from discontinuation of all therapy.

  6. Chemotherapy with cyclophosphamide, vincristine, cytosine arabinoside, and prednisone (COAP) in childhood acute lymphoblastic leukemia (ALL).

    Science.gov (United States)

    Sallan, S E; Camitta, B M; Chan, D M; Traggis, D; Jaffe, N

    1977-01-01

    Three groups of children with acute lymphoblastic leukemia (ALL) were treated with intermittent cyclophosphamide, vincristine, cytosine arabinoside, and prednisone (COAP). Group A (no prior relapse) and Group B (prior single-agent relapse) received COAP after 12 months on another chemotherapy regimen. Children in Group C (prior relapse on multiagent regimens) received COAP following A-COAP (asparaginase plus COAP) reinduction. Median disease-free survival after beginning COAP was not reached for Group A, but was only 7 months for Groups B and C. As of November 1976, there were 8 of 15 Group A patients, 1 of 12 Group B patients, and 1 of 28 Group C patients who had remained disease-free from 38 to 60 (median 54.5) months and were off chemotherapy. COAP has activity in childhood ALL. However, effectiveness is markedly diminished in patients with prior bone marrow relapse.

  7. [Long-term survival in childhood acute lymphocitic leukemia (author's transl)].

    Science.gov (United States)

    González-Martín, M C; Muñóz Villa, A; García-Miguel, P; Herrero Díez, A; Hurtado Ruano, T; Fernández Epifanio, J L

    1978-01-01

    Long-term results in the treatment of 116 patients of acute lymphocitic leukemia with ages between six months and seven years are reported. A first group A, formed by 76 patients, was treated with prednisone and vincristine as induction protocol and maintenance therapy with 6-mercaptopurine or methotrexate. No neuromeningeal prophylaxis was made, except some cases in which intratecal methotrexate was applied. 27 patients are alive, 21 of them (27,6%) remain in complete remission for more than three years. A second group B, formed by 40 patients, was treated more recently; with an induction protocol composed by prednisone, vincristine and L-asparaginase. All patients in this group received cranial irradiation and intratecal methotrexate. 31 patients are alive (77,5%), 13 of them (32,5%) remain in complete remission for more than two years. The evolution period in this group B is shorter, but some features are exposed which suggest the possibility of long-term better results.

  8. Role of radiation therapy in the treatment of pediatric non-Hodgkin's lymphomas. [Complications of local irradiation and chemotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Carabell, S.C.; Cassady, J.R.; Weinstein, H.J.; Jaff, N.

    1978-11-01

    Between 1971 and 1976, 64 patients less than 18 years of age with non-Hodgkin's lymphoma were treated at Boston's Children's Hospital Medical Center-Joint Center for Radiation Therapy. A multimodality approach was used, consisting of radiation therapy (3500 to 4500 rad), surgery, and chemotherapy. Since 1973, all patients have received a regimen initially comprising Adriamycin, Prednisone, 6-Mercaptopurine, Vincristine, and L-Asparaginase. Methotrexate was substituted for Adriamycin following a cumulative total dose of 450 mg/m/sup 2/. The 5-year actuarial survival for all patients was 61%, while relapse-free survival was 54%. The actuarial and relapse-free survival for patients presenting with localized disease was 75% and 72%, respectively. Median follow-up was 40 months and all relapses occurred within 24 months of initial therapy. A multidisciplinary approach, such as the current regimen, offers a good prognosis for this disease.

  9. Semi-permeable coatings fabricated from comb-polymers efficiently protect proteins in vivo

    Science.gov (United States)

    Liu, Mi; Johansen, Pål; Zabel, Franziska; Leroux, Jean-Christophe; Gauthier, Marc A.

    2014-11-01

    In comparison to neutral linear polymers, functional and architecturally complex (that is, non-linear) polymers offer distinct opportunities for enhancing the properties and performance of therapeutic proteins. However, understanding how to harness these parameters is challenging, and studies that capitalize on them in vivo are scarce. Here we present an in vivo demonstration that modification of a protein with a polymer of appropriate architecture can impart low immunogenicity, with a commensurably low loss of therapeutic activity. These combined properties are inaccessible by conventional strategies using linear polymers. For the model protein L-asparaginase, a comb-polymer bio-conjugate significantly outperformed the linear polymer control in terms of lower immune response and more sustained bioactivity. The semi-permeability characteristics of the coatings are consistent with the phase diagram of the polymer, which will facilitate the application of this strategy to other proteins and with other therapeutic models.

  10. Aggressive NK-cell leukemia: A rare entity with diagnostic and therapeutic challenge

    Directory of Open Access Journals (Sweden)

    Alia Nazarullah

    2016-06-01

    Full Text Available Aggressive natural killer cell leukemia (ANKL is a rare neoplasm of mature natural killer cells, with an extremely poor overall survival, which is almost always EBV related, with majority of cases reported in East Asia. Here we report the case of an ANKL presenting in a young Hispanic male with secondary hemophagocytosis. Aggressive clinical course, high EBV DNA levels and leukemic presentation, often with associated hemophagocytosis, should raise suspicion of an NK/T-cell neoplasm like ANKL. Due to significant diagnostic overlap with extranodal NK/T-cell lymphoma, nasal type (ENKL, accurate diagnostic classification is crucial due to differing treatment and prognosis. L-asparaginase including chemotherapy followed by allogeneic stem cell transplantation appears to slightly prolong overall survival, but relapse is almost inevitable. Clinical monitoring of EBV DNA levels shows good correlation with disease activity.

  11. The complex clinical picture of presumably allergic side effects to cytostatic drugs: symptoms, pathomechanism, reexposure, and desensitization.

    Science.gov (United States)

    Pagani, Mauro

    2010-07-01

    The number of drugs used for the treatment of different types of cancers is constantly increasing and actually exceeds 100 distinct chemical formulations. The use of most cytotoxic agents is associated with potential hypersensitivity reactions, and the constant increase of their administration has caused an increase in incidence of these adverse effects, thus becoming a relevant problem for clinicians. Hypersensitivity reactions are common with platinum compounds, L-asparaginase, taxanes, procarbazine, and epipodophyllotoxins, whereas they are unusual, but always possible, with the other chemotherapeutic drugs. Reactions associated with individual drugs are discussed in detail. The mechanism underlying these hypersensitivity reactions involves IgE-mediated hypersensitivity reactions, nonallergic hypersensitivity reactions, and a few pathogenetically unclear reactions. More studies are needed to better understand, diagnose, treat, and prevent these reactions. To achieve this goal, a multidisciplinary approach to treat patients with cancer who have potential allergies is needed.

  12. Treatment of acute lymphoblastic leukaemia (ALL).

    Science.gov (United States)

    Jacobs, P; Wood, L

    1992-08-01

    Forty-six consecutive patients with acute lymphoblastic leukaemia (ALL), having a median age of 23 years (range 14 to 64), underwent induction and consolidation chemotherapy with weekly parenteral vincristine, adriamycin, l-asparaginase and daily oral prednisone (VAAP), followed by standard central nervous system (CNS) prophylaxis. Maintenance therapy was given for 3 years and consisted of daily 6-mercaptopurine, weekly methotrexate, and monthly intrathecal chemotherapy, with drug intensification comprising either vincristine, adriamycin and l-asparaginase (VAA) or cyclophosphamide, vincristine, cytosine arabinoside and prednisone (COAP). Complete remission (CR) was achieved in 36 patients (78%) and only the FAB L1 morphology was a significant predictive factor (Chi-squared = 3.91: p < 0.05). Eight of the 10 non-responders had significant drug resistance and 3 deaths were associated with marrow hypoplasia. Median follow-up is 52 months. Median duration of CR is 28 months, median survival of all patients is 16 months, and for those who achieved CR is 44 months. There was no difference between the two maintenance arms. Significant prognostic factors for survival are French-American-British (FAB) subtype, in which the L1 is better than L2 (p = 0.05), and age (p = 0.035). Nineteen patients have experienced medullary relapse and 7 (37%) achieved subsequent CR; this is durable in a single patient who underwent allogeneic bone marrow transplantation. Eight patients (17%) had CNS disease at diagnosis; 5 achieved CR and 1 is alive and disease-free at 65+ months. There has been 1 CNS relapse. These results demonstrate that prolonged remissions and survival can be achieved with this protocol and many patients possibly cured. The level of toxicity is acceptable and the pattern of induction failure indicates that a margin exists for intensifying chemotherapy and thereby possibly further improving results.

  13. Elevated CO2 benefits the soil microenvironment in the rhizosphere of Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.

    Science.gov (United States)

    Huang, Shuping; Jia, Xia; Zhao, Yonghua; Bai, Bo; Chang, Yafei

    2017-02-01

    Soil contamination by heavy metals in combination with elevated atmospheric CO2 has important effects on the rhizosphere microenvironment by influencing plant growth. Here, we investigated the response of the R. pseudoacacia rhizosphere microenvironment to elevated CO2 in combination with cadmium (Cd)- and lead (Pb)-contamination. Organic compounds (total soluble sugars, soluble phenolic acids, free amino acids, and organic acids), microbial abundance and activity, and enzyme activity (urease, dehydrogenase, invertase, and β-glucosidase) in rhizosphere soils increased significantly (p soil microbial community in the rhizosphere. Heavy metals alone resulted in an increase in total soluble sugars, free amino acids, and organic acids, a decrease in phenolic acids, microbial populations and biomass, and enzyme activity, and a change in microbial community in rhizosphere soils. Elevated CO2 led to an increase in organic compounds, microbial populations, biomass, and activity, and enzyme activity (except for l-asparaginase), and changes in microbial community under Cd, Pb, or Cd + Pb treatments relative to ambient CO2. In addition, elevated CO2 significantly (p soils. Overall, elevated CO2 benefited the rhizosphere microenvironment of R. pseudoacacia seedlings under heavy metal stress, which suggests that increased atmospheric CO2 concentrations could have positive effects on soil fertility and rhizosphere microenvironment under heavy metals.

  14. Final results of a single institution experience with a pediatric-based regimen, the augmented Berlin-Frankfurt-Münster, in adolescents and young adults with acute lymphoblastic leukemia, and comparison to the hyper-CVAD regimen.

    Science.gov (United States)

    Rytting, Michael E; Jabbour, Elias J; Jorgensen, Jeffrey L; Ravandi, Farhad; Franklin, Anna R; Kadia, Tapan M; Pemmaraju, Naveen; Daver, Naval G; Ferrajoli, Alessandra; Garcia-Manero, Guillermo; Konopleva, Marina Y; Borthakur, Gautam; Garris, Rebecca; Wang, Sa; Pierce, Sherry; Schroeder, Kurt; Kornblau, Steven M; Thomas, Deborah A; Cortes, Jorge E; O'Brien, Susan M; Kantarjian, Hagop M

    2016-08-01

    Several studies reported improved outcomes of adolescents and young adults (AYA) with acute lymphoblastic leukemia (ALL) treated with pediatric-based ALL regimens. This prompted the prospective investigation of a pediatric Augmented Berlin-Frankfurt-Münster (ABFM) regimen, and its comparison with hyper-fractionated cyclophosphamide, vincristine, Adriamycin, and dexamethasone (hyper-CVAD) in AYA patients. One hundred and six AYA patients (median age 22 years) with Philadelphia chromosome- (Ph) negative ALL received ABFM from October 2006 through March 2014. Their outcome was compared to 102 AYA patients (median age 27 years), treated with hyper-CVAD at our institution. The complete remission (CR) rate was 93% with ABFM and 98% with hyper-CVAD. The 5-year complete remission duration (CRD) were 53 and 55%, respectively (P = 0.98). The 5-year overall survival (OS) rates were 60 and 60%, respectively. The MRD status on Day 29 and Day 84 of therapy was predictive of long-term outcomes on both ABFM and hyper-CVAD. Severe regimen toxicities with ABFM included hepatotoxicity in 41%, pancreatitis in 11%, osteonecrosis in 9%, and thrombosis in 19%. Myelosuppression-associated complications were most significant with hyper-CVAD. In summary, ABFM and hyper-CVAD resulted in similar efficacy outcomes, but were associated with different toxicity profiles, asparaginase-related with ABFM and myelosuppression-related with hyper-CVAD. Am. J. Hematol. 91:819-823, 2016. © 2016 Wiley Periodicals, Inc.

  15. Biotechnology development for biomedical applications.

    Energy Technology Data Exchange (ETDEWEB)

    Kuehl, Michael; Brozik, Susan Marie; Rogers, David Michael; Rempe, Susan L.; Abhyankar, Vinay V.; Hatch, Anson V.; Dirk, Shawn M.; Hedberg-Dirk, Elizabeth (University of New Mexico, Albuquerque, NM); Sukharev, Sergei (University of Maryland, College Park, MD); Anishken, Andriy (University of Maryland, College Park, MD); Cicotte, Kirsten; De Sapio, Vincent; Buerger, Stephen P.; Mai, Junyu

    2010-11-01

    Sandia's scientific and engineering expertise in the fields of computational biology, high-performance prosthetic limbs, biodetection, and bioinformatics has been applied to specific problems at the forefront of cancer research. Molecular modeling was employed to design stable mutations of the enzyme L-asparaginase with improved selectivity for asparagine over other amino acids with the potential for improved cancer chemotherapy. New electrospun polymer composites with improved electrical conductivity and mechanical compliance have been demonstrated with the promise of direct interfacing between the peripheral nervous system and the control electronics of advanced prosthetics. The capture of rare circulating tumor cells has been demonstrated on a microfluidic chip produced with a versatile fabrication processes capable of integration with existing lab-on-a-chip and biosensor technology. And software tools have been developed to increase the calculation speed of clustered heat maps for the display of relationships in large arrays of protein data. All these projects were carried out in collaboration with researchers at the University of Texas M. D. Anderson Cancer Center in Houston, TX.

  16. Infections During Induction Therapy of Protocol CCLG-2008 in Childhood Acute Lymphoblastic Leukemia: A Single-center Experience with 256 Cases in China

    Institute of Scientific and Technical Information of China (English)

    Si-Dan Li; Yong-Bing Chen; Zhi-Gang Li; Run-Hui Wu; Mao-Quan Qin; Xuan Zhou; Jin Jiang

    2015-01-01

    Background:Infections remain a major cause of therapy-associated morbidity and mortality in children with acute lymphoblastic leukemia (ALL).Methods:We retrospectively analyzed the medical charts of 256 children treated for ALL under the CCLG-2008 protocol in Beijing Children's Hospital.Results:There were 65 infectious complications in 50 patients during vincristine,daunorubicin,L-asparaginase and dexamethasone induction therapy,including microbiologically documented infections (n =12; 18.5%),clinically documented infections (n =23; 35.3%) and fever of unknown origin (n =30; 46.2%).Neutropenia was present in 83.1% of the infectious episodes.In all,most infections occurred around the 15t1h day of induction treatment (n =28),and no patients died of infection-associated complications.Conclusions:The infections in this study was independent of treatment response,minimal residual diseases at the end of induction therapy,gender,immunophenotype,infection at first visit,risk stratification at diagnosis,unfavorable karyotypes at diagnosis and morphologic type.The infection rate of CCLG-2008 induction therapy is low,and the outcome of patients is favorable.

  17. Elevated temperature altered photosynthetic products in wheat seedlings and organic compounds and biological activity in rhizopshere soil under cadmium stress

    Science.gov (United States)

    Jia, Xia; Zhao, Yonghua; Wang, Wenke; He, Yunhua

    2015-09-01

    The objective of this study was to investigate the effects of slightly elevated atmospheric temperature in the spring on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated temperature was associated with increased soluble sugars, reducing sugars, starch, and total sugars, and with decreased amino acids in wheat seedlings under Cd stress. Elevated temperature improved total soluble sugars, free amino acids, soluble phenolic acids, and organic acids in rhizosphere soil under Cd stress. The activity of amylase, phenol oxidase, invertase, β-glucosidase, and L-asparaginase in rhizosphere soil was significantly improved by elevated temperature under Cd stress; while cellulase, neutral phosphatase, and urease activity significantly decreased. Elevated temperature significantly improved bacteria, fungi, actinomycetes, and total microorganisms abundance and fluorescein diacetate activity under Cd stress. In conclusion, slightly elevated atmospheric temperature in the spring improved the carbohydrate levels in wheat seedlings and organic compounds and biological activity in rhizosphere soil under Cd stress in the short term. In addition, elevated atmospheric temperature in the spring stimulated available Cd by affecting pH, DOC, phenolic acids, and organic acids in rhizosphere soil, which resulted in the improvement of the Cd uptake by wheat seedlings.

  18. Single QTL mapping and nucleotide-level resolution of a physiologic trait in wine Saccharomyces cerevisiae strains.

    Science.gov (United States)

    Marullo, Philippe; Aigle, Michel; Bely, Marina; Masneuf-Pomarède, Isabelle; Durrens, Pascal; Dubourdieu, Denis; Yvert, Gaël

    2007-09-01

    Natural Saccharomyces cerevisiae yeast strains exhibit very large genotypic and phenotypic diversity. However, the link between phenotype variation and genetic determinism is still difficult to identify, especially in wild populations. Using genome hybridization on DNA microarrays, it is now possible to identify single-feature polymorphisms among divergent yeast strains. This tool offers the possibility of applying quantitative genetics to wild yeast strains. In this instance, we studied the genetic basis for variations in acetic acid production using progeny derived from two strains from grape must isolates. The trait was quantified during alcoholic fermentation of the two strains and 108 segregants derived from their crossing. A genetic map of 2212 markers was generated using oligonucleotide microarrays, and a major quantitative trait locus (QTL) was mapped with high significance. Further investigations showed that this QTL was due to a nonsynonymous single-nucleotide polymorphism that targeted the catalytic core of asparaginase type I (ASP1) and abolished its activity. This QTL was only effective when asparagine was used as a major nitrogen source. Our results link nitrogen assimilation and CO(2) production rate to acetic acid production, as well as, on a broader scale, illustrating the specific problem of quantitative genetics when working with nonlaboratory microorganisms.

  19. Enzymes approved for human therapy: indications, mechanisms and adverse effects.

    Science.gov (United States)

    Baldo, Brian A

    2015-02-01

    Research and drug developments fostered under orphan drug product development programs have greatly assisted the introduction of efficient and safe enzyme-based therapies for a range of rare disorders. The introduction and regulatory approval of 20 different recombinant enzymes has enabled, often for the first time, effective enzyme-replacement therapy for some lysosomal storage disorders, including Gaucher (imiglucerase, taliglucerase, and velaglucerase), Fabry (agalsidase alfa and beta), and Pompe (alglucosidase alfa) diseases and mucopolysaccharidoses I (laronidase), II (idursulfase), IVA (elosulfase), and VI (galsulfase). Approved recombinant enzymes are also now used as therapy for myocardial infarction (alteplase, reteplase, and tenecteplase), cystic fibrosis (dornase alfa), chronic gout (pegloticase), tumor lysis syndrome (rasburicase), leukemia (L-asparaginase), some collagen-based disorders such as Dupuytren's contracture (collagenase), severe combined immunodeficiency disease (pegademase bovine), detoxification of methotrexate (glucarpidase), and vitreomacular adhesion (ocriplasmin). The development of these efficacious and safe enzyme-based therapies has occurred hand in hand with some remarkable advances in the preparation of the often specifically designed recombinant enzymes; the manufacturing expertise necessary for commercial production; our understanding of underlying mechanisms operative in the different diseases; and the mechanisms of action of the relevant recombinant enzymes. Together with information on these mechanisms, safety findings recorded so far on the various adverse events and problems of immunogenicity of the recombinant enzymes used for therapy are presented.

  20. The periplasmic enzyme, AnsB, of Shigella flexneri modulates bacterial adherence to host epithelial cells.

    Directory of Open Access Journals (Sweden)

    Divya T George

    Full Text Available S. flexneri strains, most frequently linked with endemic outbreaks of shigellosis, invade the colonic and rectal epithelium of their host and cause severe tissue damage. Here we have attempted to elucidate the contribution of the periplasmic enzyme, L-asparaginase (AnsB to the pathogenesis of S. flexneri. Using a reverse genetic approach we found that ansB mutants showed reduced adherence to epithelial cells in vitro and attenuation in two in vivo models of shigellosis, the Caenorhabditis elegans and the murine pulmonary model. To investigate how AnsB affects bacterial adherence, we compared the proteomes of the ansB mutant with its wild type parental strain using two dimensional differential in-gel electrophoresis and identified the outer membrane protein, OmpA as up-regulated in ansB mutant cells. Bacterial OmpA, is a prominent outer membrane protein whose activity has been found to be required for bacterial pathogenesis. Overexpression of OmpA in wild type S. flexneri serotype 3b resulted in decreasing the adherence of this virulent strain, suggesting that the up-regulation of OmpA in ansB mutants contributes to the reduced adherence of this mutant strain. The data presented here is the first report that links the metabolic enzyme AnsB to S. flexneri pathogenesis.

  1. Concurrent Epstein-Barr virus associated NK/T cell lymphoma after immunosuppressive therapy for aplastic anemia: report of a case and review of literature.

    Science.gov (United States)

    Yin, Guangli; Ni, Ying; Xiao, Zhengrui; He, Guangsheng; Miao, Kourong

    2015-01-01

    Aplastic anemia (AA) patients with prolonged immunosuppression have a risk of development of lymphoproliferative disorders (LPDs), especially combined with Epstein-Barr virus (EBV) infection. However, development of nature killer/T (NK/T) cell lymphoma, in a nontransplantation setting, has not been documented for AA patients with immunosuppressive therapy (IST). Herein, we described a middle-aged man, Han ethnic, who presented with swelled parotid gland after a long history of IST for AA. Fever, night sweating, weight loss had not been found. Increased heterotypic lymphocytes had been detected in the left side of parotid gland demonstrated as cCD3(+), CD56(+), GranB(+), TIA-1(+), MUM-1(+), KI-67 (50%-75%)(++), Bcl-6(-), MPO(-) by immunohistochemistry, and in-situ hybridization (ISH) indicated EBER positive. Chromosome analysis by R banding method revealed 46, XY [20]. NK/T cell lymphoma concurrent with aplastic anemia was diagnosed and a mild chemotherapy regimen including vincristine, prednisone, L-asparaginase was administered. The parotid mass was gradually regressed after the first cycle of chemotherapy. The patient discharged from the hospital voluntarily and lost the follow-up.

  2. TFDP3 confers chemoresistance in minimal residual disease within childhood T-cell acute lymphoblastic leukemia

    Science.gov (United States)

    Chu, Ming; Yin, Kailin; Dong, Yujun; Wang, Pingzhang; Xue, Yun; Zhou, Peng; Wang, Yuqi; Wang, Yuedan

    2017-01-01

    Acquired drug resistance in childhood T-cell acute lymphoblastic leukemia (T-ALL) remains a significant clinical problem. In this study, a novel gene therapy target for childhood T-ALL to overcome chemoresistance was discovered: TFDP3 increased in the minimal residual disease (MRD) positive childhood T-ALL patients. Then, we established a preclinical model of resistance to induction therapy to examine the functional relevance of TFDP3 to chemoresistance in MRD derived from Jurkat/E6-1. Jurkat xenografts in NOD/SCID mice were exposed to a four drug combination (VXLD) of vincristine (VCR), dexamethasone (DEX), L-asparaginase (L-asp) and daunorubicin (DNR). During the 4-week VXLD treatment, the level of TFDP3 increased 4-fold. High expression of TFDP3 was identified in the re-emerging lines (Jurkat/MRD) with increased chemoresistance, which is correlated with partially promoter demethylation of TFDP3. Downregulation of TFDP3 by RNA interference reversed chemoresistance in Jurkat/MRD accompanied by reinstated E2F1 activity that coincided with increased levels of p53, p73, and associated proapoptotic target genes. Importantly, TFDP3 silencing in vivo induced apparent benefit to overcome chemoresistance in combination with VXLD treatment. Collectively, TFDP3 confers chemoresistance in MRD within childhood T-ALL, indicating that TFDP3 is a potential gene therapy target for residual cancer. PMID:27902457

  3. IMPACT OF PRE-TREATMENTS ON THE ACRYLAMIDE FORMATION AND ORGANOLEPTIC EVOLUTION OF FRIED POTATO CHIPS

    Directory of Open Access Journals (Sweden)

    Samir Abdel-Monem Ahmed Ismial

    2013-01-01

    Full Text Available The main objective of this investigation was to study the effect of different pre-frying treatments on reduction of acrylamide formation of fried potato Moreover; the impact of different phenol compounds and leaves on acrylamide formation was evaluated. In addition, the effects of these treatments on the sensorial quality of fried potato chips were studied. Results showed that blanching process caused significant decreases in acrylamide content of fried potato. The highest decrease was observed for those samples blanched in MgCl2 (0.1 M, L-cysteine (0.05 M and 0.01 M of citric acid solutions, 97.97, 97.17 and 93.43%, respectively. Soaking of potato slices in water or different solutions significantly reduced the formation of acrylamide. The decreases in acrylamide content ranged from 61.61 to 97.47%. Soaking in crude, semi-purified asparaginase solutions, blanching in hot water plus immersing in the enzyme solutions and soaking in phenolic acid solutions caused significant reduction in the formation of acrylamide of potato chips. Addition of fresh leaves into frying oil significantly influenced acrylamide formation. Oregano, rosemary, bamboo, guava and olive leaves caused the greatest reductions. Potato slices blanched in distilled water at 65°C, NaCl, Mg Cl2 and 0.1 M glutamine had significantly the highest scores of overall acceptability.

  4. Integrative computational in-depth analysis of dysregulated miRNA-mRNA interactions in drug-resistant pediatric acute lymphoblastic leukemia cells: an attempt to obtain new potential gene-miRNA pathways involved in response to treatment.

    Science.gov (United States)

    Mesrian Tanha, Hamzeh; Mojtabavi Naeini, Marjan; Rahgozar, Soheila; Moafi, Alireza; Honardoost, Mohammad Amin

    2016-06-01

    Acute lymphoblastic leukemia (ALL) is the major neoplasia type among children. Despite the tremendous success of current treatment strategies, drug resistance still remains a major cause of chemotherapy failure and relapse in pediatric patients. Overwhelming evidence illustrates that microRNAs (miRNAs) act as post-transcriptional regulators of drug-resistance-related genes. The current study was aimed at how dysregulated miRNA-mRNA-signaling pathway interaction networks mediate resistance to four commonly used chemotherapy agents in pediatric ALL, including asparaginase, daunorubicin, prednisolone, and vincristine. Using public expression microarray datasets, a holistic in silico approach was utilized to investigate candidate drug resistance miRNA-mRNA-signaling pathway interaction networks in pediatric ALL. Our systems biology approach nominated significant drug resistance and cross-resistance miRNAs, mRNAs, and cell signaling pathways based on anti-correlative relationship between miRNA and mRNA expression pattern. To sum up, our systemic analysis disclosed either a new potential role of miRNAs, or a possible mechanism of cellular drug resistance, in chemotherapy resistance of pediatric ALL. The current study may shed light on predicting drug response and overcoming drug resistance in childhood ALL for subsequent generations of chemotherapies.

  5. Decreased PARP and procaspase-2 protein levels are associated with cellular drug resistance in childhood acute lymphoblastic leukemia.

    Science.gov (United States)

    Holleman, Amy; den Boer, Monique L; Kazemier, Karin M; Beverloo, H Berna; von Bergh, Anne R M; Janka-Schaub, Gritta E; Pieters, Rob

    2005-09-01

    Drug resistance in childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) is associated with impaired ability to induce apoptosis. To elucidate causes of apoptotic defects, we studied the protein expression of Apaf-1, procaspases-2, -3, -6, -7, -8, -10, and poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) in cells from children with acute lymphoblastic leukemia (ALL; n = 43) and acute myeloid leukemia (AML; n = 10). PARP expression was present in all B-lineage samples, but absent in 4 of 15 T-lineage ALL samples and 3 of 10 AML cases, which was not caused by genomic deletions. PARP expression was a median 7-fold lower in T-lineage ALL (P < .001) and 10-fold lower in AML (P < .001) compared with B-lineage ALL. PARP expression was 4-fold lower in prednisolone, vincristine and L-asparaginase (PVA)-resistant compared with PVA-sensitive ALL patients (P < .001). Procaspase-2 expression was 3-fold lower in T-lineage ALL (P = .022) and AML (P = .014) compared with B-lineage ALL. In addition, procaspase-2 expression was 2-fold lower in PVA-resistant compared to PVA-sensitive ALL patients (P = .042). No relation between apoptotic protease-activating factor 1 (Apaf-1), procaspases-3, -6, -7, -8, -10, and drug resistance was found. In conclusion, low baseline expression of PARP and procaspase-2 is related to cellular drug resistance in childhood acute lymphoblastic leukemia.

  6. Salinidade, sodicidade e propriedades microbiológicas de Argissolo cultivado com erva-sal e irrigado com rejeito salino Salinity, sodicity and microbiological properties of an Ultisol cultivated with saltbush and irrigated with saline effluents

    Directory of Open Access Journals (Sweden)

    Célia Maria Maganhotto de Souza Silva

    2008-10-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da irrigação com rejeito da dessalinização, oriundo de tanques de produção de tilápia-rosa, sobre as propriedades químicas e microbiológicas de solos cultivados com erva-sal (Atriplex nummularia Lindl.. Quatro áreas foram usadas, das quais duas foram irrigadas com rejeito salino e cultivadas, durante um e cinco anos, com erva-sal. As outras duas áreas foram conduzidas sem irrigação: uma cultivada com vegetação natural e outra com a halófita. Avaliaram-se os parâmetros relativos à salinidade e sodicidade do solo, e também as seguintes características: carbono da biomassa microbiana (Cmic; relação Cmic/carbono orgânico; atividade das enzimas fosfatase ácida, fosfatase alcalina, beta-glucosidase, protease, L-asparaginase, L-glutaminase. A adição de sais afetou as propriedades físicas e químicas dos solos irrigados com rejeito salino, com tendência à salinização e sodificação. A salinidade afetou as propriedades microbiológicas nos solos irrigados, mas o cultivo da halófita favoreceu a produção das enzimas estudadas. O cultivo da erva-sal em áreas que recebem rejeito salino pela irrigação melhora a qualidade biológica dos solos e sua fertilidade, mas não impede a salinização.The objective of this work was to evaluate the effects of irrigation with saline effluents, from red tilapia production ponds, on chemical and microbiological properties of soils cultivated with saltbush (Atriplex nummularia Lindl. Four areas were used, from which two were irrigated with saline waste and cultivated with A. nummularia, during one and five years. The other two areas were not irrigated, and one was cultivated with natural vegetation and the other with the halophyte. The parameters related to soil salinity and sodicity were evaluated, as well as the following characteristics: microbial biomass carbon (Cmic; Cmic/organic carbon; the activity of acid and alcaline phosphatase

  7. Multi-agent chemotherapy overcomes glucocorticoid resistance conferred by a BIM deletion polymorphism in pediatric acute lymphoblastic leukemia.

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    Soh, Sheila Xinxuan; Lim, Joshua Yew Suang; Huang, John W J; Jiang, Nan; Yeoh, Allen Eng Juh; Ong, S Tiong

    2014-01-01

    A broad range of anti-cancer agents, including glucocorticoids (GCs) and tyrosine kinase inhibitors (TKIs), kill cells by upregulating the pro-apoptotic BCL2 family member, BIM. A common germline deletion in the BIM gene was recently shown to favor the production of non-apoptotic BIM isoforms, and to predict inferior responses in TKI-treated chronic myeloid leukemia (CML) and EGFR-driven lung cancer patients. Given that both in vitro and in vivo GC resistance are predictive of adverse outcomes in acute lymphoblastic leukemia (ALL), we hypothesized that this polymorphism would mediate GC resistance, and serve as a biomarker of poor response in ALL. Accordingly, we used zinc finger nucleases to generate ALL cell lines with the BIM deletion, and confirmed the ability of the deletion to mediate GC resistance in vitro. In contrast to CML and lung cancer, the BIM deletion did not predict for poorer clinical outcome in a retrospective analysis of 411 pediatric ALL patients who were uniformly treated with GCs and chemotherapy. Underlying the lack of prognostic significance, we found that the chemotherapy agents used in our cohort (vincristine, L-asparaginase, and methotrexate) were each able to induce ALL cell death in a BIM-independent fashion, and resensitize BIM deletion-containing cells to GCs. Together, our work demonstrates how effective therapy can overcome intrinsic resistance in ALL patients, and suggests the potential of using combinations of drugs that work via divergent mechanisms of cell killing to surmount BIM deletion-mediated drug resistance in other cancers.

  8. Treatment of isolated testicular relapse in childhood acute lymphoblastic leukemia: an Italian multicenter study. Associazione Italiana Ematologia ed Oncologia Pediatrica.

    Science.gov (United States)

    Uderzo, C; Grazia Zurlo, M; Adamoli, L; Zanesco, L; Aricò, M; Calculli, G; Comelli, A; Cordero di Montezemolo, L; Di Tullio, M T; Guazzelli, C

    1990-04-01

    Between May 1980 and April 1987, 49 children with acute lymphoblastic leukemia (ALL) in isolated testicular and first leukemia relapse (ITR) were enrolled in the Associazione Italiana Ematologia ed Oncologia Pediatrica (AIEOP) multicenter study REC80-ITR. According to the Rome Workshop criteria, 77% were at standard and 23% at high initial prognostic risk. In 33% of the cases, ITR occurred during first treatment. The REC80-ITR protocol consisted of an induction phase regimen of vincristine (VCR), cytarabine (ARA-C), methotrexate (MTX), and asparaginase (L-asp), and bilateral testicular irradiation, and CNS prophylaxis with intrathecal MTX and a maintenance phase with a multidrug rotating regimen. Total treatment duration was 30 months. The median time of observation after ITR was 51 months. The Kaplan-Meier estimates of survival and disease-free survival (DFS) at 4 years were 67.7% and 41%, respectively. Patients who had an ITR on therapy or within the first off-therapy year showed the poorest outcome. The DFS at 3 years was 20%, 47.6%, and 100%, respectively, for children who had an ITR on treatment (n = 16), within the first year of treatment withdrawal (n = 22), or later (n = 10) (P = .001). Patients with an asymptomatic occult testicular infiltrate at treatment discontinuation had a very unfavorable prognosis. Eighty-one percent of second relapses involved the bone marrow. In our experience, children presenting an early ITR (ie, within 6 months of treatment withdrawal) need a very aggressive treatment because of the high probability of an underlying systemic disease. On the other hand, patients with a late ITR seem to have a truly local recurrence and can apparently be cured by standard protocols, as shown in protocol REC80-ITR.

  9. Elevated atmospheric CO2 affected photosynthetic products in wheat seedlings and biological activity in rhizosphere soil under cadmium stress.

    Science.gov (United States)

    Jia, Xia; Liu, Tuo; Zhao, Yonghua; He, Yunhua; Yang, Mingyan

    2016-01-01

    The objective of this study was to investigate the effects of elevated CO2 (700 ± 23 μmol mol(-1)) on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated CO2 was associated with decreased quantities of reducing sugars, starch, and soluble amino acids, and with increased quantities of soluble sugars, total sugars, and soluble proteins in wheat seedlings under Cd stress. The contents of total soluble sugars, total free amino acids, total soluble phenolic acids, and total organic acids in the rhizosphere soil under Cd stress were improved by elevated CO2. Compared to Cd stress alone, the activity of amylase, phenol oxidase, urease, L-asparaginase, β-glucosidase, neutral phosphatase, and fluorescein diacetate increased under elevated CO2 in combination with Cd stress; only cellulase activity decreased. Bacterial abundance in rhizosphere soil was stimulated by elevated CO2 at low Cd concentrations (1.31-5.31 mg Cd kg(-1) dry soil). Actinomycetes, total microbial abundance, and fungi decreased under the combined conditions at 5.31-10.31 mg Cd kg(-1) dry soil. In conclusion, increased production of soluble sugars, total sugars, and proteins in wheat seedlings under elevated CO2 + Cd stress led to greater quantities of organic compounds in the rhizosphere soil relative to seedlings grown under Cd stress only. Elevated CO2 concentrations could moderate the effects of heavy metal pollution on enzyme activity and microorganism abundance in rhizosphere soils, thus improving soil fertility and the microecological rhizosphere environment of wheat under Cd stress.

  10. Taspase1: a 'misunderstood' protease with translational cancer relevance.

    Science.gov (United States)

    Wünsch, D; Hahlbrock, A; Jung, S; Schirmeister, T; van den Boom, J; Schilling, O; Knauer, S K; Stauber, R H

    2016-06-30

    Proteolysis is not only a critical requirement for life, but the executing enzymes also play important roles in numerous pathological conditions, including cancer. Therefore, targeting proteases is clearly relevant for improving cancer patient care. However, to effectively control proteases, a profound knowledge of their mechanistic function as well as their regulation and downstream signalling in health and disease is required. The highly conserved protease Threonine Aspartase1 (Taspase1) is overexpressed in numerous liquid and solid malignancies and was characterized as a 'non-oncogene addiction' protease. Although Taspase1 was shown to cleave various regulatory proteins in humans as well as leukaemia provoking mixed lineage leukaemia fusions, our knowledge on its detailed functions and the underlying mechanisms contributing to cancer is still incomplete. Despite superficial similarity to type 2 asparaginases as well as Ntn proteases, such as the proteasome, Taspase1-related research so far gives us the picture of a unique protease exhibiting special features. Moreover, neither effective genetic nor chemical inhibitors for this enzyme are available so far, thus hampering not only to further dissect Taspase1's pathobiological functions but also precluding the assessment of its clinical impact. Based on recent insights, we here critically review the current knowledge of Taspase1's structure-function relationship and its mechanistic relevance for tumorigenesis obtained from in vitro and in vivo cancer models. We provide a comprehensive overview of tumour entities for which Taspase1 might be of predictive and therapeutic value, and present the respective experimental evidence. To stimulate progress in the field, a comprehensive overview of Taspase1 targeting approaches is presented, including coverage of Taspase1-related patents. We conclude by discussing future inhibition strategies and relevant challenges, which need to be resolved by the field.

  11. Review of methods for the reduction of dietary content and toxicity of acrylamide.

    Science.gov (United States)

    Friedman, Mendel; Levin, Carol E

    2008-08-13

    Potentially toxic acrylamide is largely derived from heat-induced reactions between the amino group of the free amino acid asparagine and carbonyl groups of glucose and fructose in cereals, potatoes, and other plant-derived foods. This overview surveys and consolidates the following dietary aspects of acrylamide: distribution in food originating from different sources; consumption by diverse populations; reduction of the acrylamide content in the diet; and suppression of adverse effects in vivo. Methods to reduce adverse effects of dietary acrylamide include (a) selecting potato, cereal, and other plant varieties for dietary use that contain low levels of the acrylamide precursors, namely, asparagine and glucose; (b) removing precursors before processing; (c) using the enzyme asparaginase to hydrolyze asparagine to aspartic acid; (d) selecting processing conditions (pH, temperature, time, processing and storage atmosphere) that minimize acrylamide formation; (e) adding food ingredients (acidulants, amino acids, antioxidants, nonreducing carbohydrates, chitosan, garlic compounds, protein hydrolysates, proteins, metal salts) that have been reported to prevent acrylamide formation; (f) removing/trapping acrylamide after it is formed with the aid of chromatography, evaporation, polymerization, or reaction with other food ingredients; and (g) reducing in vivo toxicity. Research needs are suggested that may further facilitate reducing the acrylamide burden of the diet. Researchers are challenged to (a) apply the available methods and to minimize the acrylamide content of the diet without adversely affecting the nutritional quality, safety, and sensory attributes, including color and flavor, while maintaining consumer acceptance; and (b) educate commercial and home food processors and the public about available approaches to mitigating undesirable effects of dietary acrylamide.

  12. Identification and Molecular Characterization of Genes Coding Pharmaceutically Important Enzymes from Halo-Thermo Tolerant Bacillus

    Science.gov (United States)

    Safary, Azam; Moniri, Rezvan; Hamzeh-Mivehroud, Maryam; Dastmalchi, Siavoush

    2016-01-01

    Purpose: Robust pharmaceutical and industrial enzymes from extremophile microorganisms are main source of enzymes with tremendous stability under harsh conditions which make them potential tools for commercial and biotechnological applications. Methods: The genome of a Gram-positive halo-thermotolerant Bacillus sp. SL1, new isolate from Saline Lake, was investigated for the presence of genes coding for potentially pharmaceutical enzymes. We determined gene sequences for the enzymes laccase (CotA), l-asparaginase (ansA3, ansA1), glutamate-specific endopeptidase (blaSE), l-arabinose isomerase (araA2), endo-1,4-β mannosidase (gmuG), glutaminase (glsA), pectate lyase (pelA), cellulase (bglC1), aldehyde dehydrogenase (ycbD) and allantoinases (pucH) in the genome of Bacillus sp. SL1. Results: Based on the DNA sequence alignment results, six of the studied enzymes of Bacillus sp. SL-1 showed 100% similarity at the nucleotide level to the same genes of B. licheniformis 14580 demonstrating extensive organizational relationship between these two strains. Despite high similarities between the B. licheniformis and Bacillus sp. SL-1 genomes, there are minor differences in the sequences of some enzyme. Approximately 30% of the enzyme sequences revealed more than 99% identity with some variations in nucleotides leading to amino acid substitution in protein sequences. Conclusion: Molecular characterization of this new isolate provides useful information regarding evolutionary relationship between B. subtilis and B. licheniformis species. Since, the most industrial processes are often performed in harsh conditions, enzymes from such halo-thermotolerant bacteria may provide economically and industrially appealing biocatalysts to be used under specific physicochemical situations in medical, pharmaceutical, chemical and other industries. PMID:28101462

  13. Central Nervous System Disease in Hematological Malignancies: Historical Perspective and Practical Applications

    Science.gov (United States)

    Pui, Ching-Hon; Thiel, Eckhard

    2009-01-01

    Acute lymphoblastic leukemia (ALL) 5-year survival rates are approaching 90% in children and 50% in adults who are receiving contemporary risk-directed treatment protocols. Current efforts focus not only on further improving cure rate but also on patient quality of life. Hence, all protocols decrease or limit the use of cranial irradiation as central nervous system (CNS)-directed therapy, even in patients with high-risk presenting features, such as the presence of leukemia cells in the cerebrospinal fluid (even resulting from traumatic lumbar puncture), adverse genetic features, T-cell immunophenotype, and a large leukemia-cell burden. Current strategies for CNS-directed therapy involve effective systemic chemotherapy (eg, dexamethasone, high-dose methotrexate, intensive asparaginase, ifosfamide) and early intensification and optimization of intrathecal therapy. Options under investigation for the treatment of relapsed or refractory CNS leukemia in ALL patients include thiotepa and intrathecal liposomal cytarabine. CNS involvement in non-Hodgkin’s lymphoma (NHL) is associated with young age, advanced stage, number of extranodal sites, elevated lactate dehydrogenase, and International Prognostic Index score. Refractory CNS lymphoma in patients with NHL carries a poor prognosis, with a median survival of 2 to 6 months; the most promising treatment, autologous stem cell transplant, can extend median survival from 10 to 26 months. CNS prophylaxis is required during the initial treatment of NHL subtypes that carry a high risk of CNS relapse, such as B-cell ALL, Burkitt’s lymphoma, and lymphoblastic lymphoma. The use of CNS prophylaxis in the treatment of diffuse large B-cell lymphoma is controversial because of the low risk of CNS relapse (~5%) in this population. In this article, we review current and past practice of intrathecal therapy in ALL and NHL and the risk-models that aim to identify predictors of CNS relapse in NHL. PMID:19660680

  14. Treatment of Childhood Acute Lymphoblastic Leukemia Without Prophylactic Cranial Irradiation

    Science.gov (United States)

    Pui, Ching-Hon; Campana, Dario; Pei, Deqing; Bowman, W. Paul; Sandlund, John T.; Kaste, Sue C.; Ribeiro, Raul C.; Rubnitz, Jeffrey E.; Raimondi, Susana C.; Onciu, Mihaela; Coustan-Smith, Elaine; Kun, Larry E.; Jeha, Sima; Cheng, Cheng; Howard, Scott C.; Simmons, Vickey; Bayles, Amy; Metzger, Monika L.; Boyett, James M.; Leung, Wing; Handgretinger, Rupert; Downing, James R.; Evans, William E.; Relling, Mary V.

    2009-01-01

    Background We conducted a clinical trial to test whether prophylactic cranial irradiation could be omitted in all children with newly diagnosed acute lymphoblastic leukemia. Methods A total of 498 evaluable patients were enrolled. Treatment intensity was based on presenting features and the level of minimal residual disease after remission induction treatment. Continuous complete remission was compared between the 71 patients who previously would have received prophylactic cranial irradiation and the 56 historical controls who received it. Results The 5-year event-free and overall survival probabilities (95% confidence interval) for all 498 patients were 85.6% (79.9% to 91.3%) and 93.5% (89.8% to 97.2%), respectively. The 5-year cumulative risk of isolated central-nervous-system (CNS) relapse was 2.7% (1.1% to 4.2%), and that of any CNS relapse (isolated plus combined) was 3.9% (1.9% to 5.9%). The 71 patients had significantly better continuous complete remission than the 56 historical controls (P=0.04). All 11 patients with isolated CNS relapse remain in second remission for 0.4 to 5.5 years. CNS leukemia (CNS-3 status) or a traumatic lumbar puncture with blasts at diagnosis and a high level of minimal residual disease (≥ 1%) after 6 weeks of remission induction were significantly associated with poorer event-free survival. Risk factors for CNS relapse included the presence of the t(1;19)[TCF3-PBX1], any CNS involvement at diagnosis, and T-cell immunophenotype. Common adverse effects included allergic reactions to L-asparaginase, osteonecrosis, thrombosis, and disseminated fungal infection. Conclusions With effective risk-adjusted chemotherapy, prophylactic cranial irradiation can be safely omitted in the treatment of childhood acute lymphoblastic leukemia. PMID:19553647

  15. Improved Prognosis for Older Adolescents With Acute Lymphoblastic Leukemia

    Science.gov (United States)

    Pui, Ching-Hon; Pei, Deqing; Campana, Dario; Bowman, W. Paul; Sandlund, John T.; Kaste, Sue C.; Ribeiro, Raul C.; Rubnitz, Jeffrey E.; Coustan-Smith, Elaine; Jeha, Sima; Cheng, Cheng; Metzger, Monika L.; Bhojwani, Deepa; Inaba, Hiroto; Raimondi, Susana C.; Onciu, Mihaela; Howard, Scott C.; Leung, Wing; Downing, James R.; Evans, William E.; Relling, Mary V.

    2011-01-01

    Purpose The prognosis for older adolescents and young adults with acute lymphoblastic leukemia (ALL) has been historically much worse than that for younger patients. We reviewed the outcome of older adolescents (age 15 to 18 years) treated in four consecutive Total Therapy studies to determine if recent improved treatment extended to this high-risk group. Patients and Methods Between 1991 and 2007, 963 pediatric patients, including 89 older adolescents, were enrolled on Total Therapy studies XIIIA, XIIIB, XIV, and XV. In the first three studies, treatment selection was based on presenting clinical features and leukemic cell genetics. In study XV, the level of residual disease was used to guide treatment, which featured intensive methotrexate, glucocorticoid, vincristine, and asparaginase, as well as early triple intrathecal therapy for higher-risk ALL. Results The 89 older adolescents were significantly more likely to have T-cell ALL, the t(4;11)(MLL-AF4), and detectable minimal residual disease during or at the end of remission induction; they were less likely to have the t(12;21)(ETV6-RUNX1) compared with younger patients. In the first three studies, the 44 older adolescents had significantly poorer event-free survival and overall survival than the 403 younger patients. This gap in prognosis was abolished in study XV: event-free survival rates at 5 years were 86.4% ± 5.2% (standard error) for the 45 older adolescents and 87.4% ± 1.7% for the 453 younger patients; overall survival rates were 87.9% ± 5.1% versus 94.1% ± 1.2%, respectively. Conclusion Most older adolescents with ALL can be cured with risk-adjusted intensive chemotherapy without stem-cell transplantation. PMID:21172890

  16. Approaches to Mitigate the Unwanted Immunogenicity of Therapeutic Proteins during Drug Development.

    Science.gov (United States)

    Salazar-Fontana, Laura I; Desai, Dharmesh D; Khan, Tarik A; Pillutla, Renuka C; Prior, Sandra; Ramakrishnan, Radha; Schneider, Jennifer; Joseph, Alexandra

    2017-03-01

    All biotherapeutics have the potential to induce an immune response. This immunological response is complex and, in addition to antibody formation, involves T cell activation and innate immune responses that could contribute to adverse effects. Integrated immunogenicity data analysis is crucial to understanding the possible clinical consequences of anti-drug antibody (ADA) responses. Because patient- and product-related factors can influence the immunogenicity of a therapeutic protein, a risk-based approach is recommended and followed by most drug developers to provide insight over the potential harm of unwanted ADA responses. This paper examines mitigation strategies currently implemented and novel under investigation approaches used by drug developers. The review describes immunomodulatory regimens used in the clinic to mitigate deleterious ADA responses to replacement therapies for deficiency syndromes, such as hemophilia A and B, and high risk classical infantile Pompe patients (e.g., cyclophosphamide, methotrexate, rituximab); novel in silico and in vitro prediction tools used to select candidates based on their immunogenicity potential (e.g., anti-CD52 antibody primary sequence and IFN beta-1a formulation); in vitro generation of tolerogenic antigen-presenting cells (APCs) to reduce ADA responses to factor VIII and IX in murine models of hemophilia; and selection of novel delivery systems to reduce in vivo ADA responses to highly immunogenic biotherapeutics (e.g., asparaginase). We conclude that mitigation strategies should be considered early in development for biotherapeutics based on our knowledge of existing clinical data for biotherapeutics and the immune response involved in the generation of these ADAs.

  17. Outcome of Childhood Acute Lymphoblastic Leukaemia after Induction Therapy --- Three-Year Experience in a Tertiary Care Hospital in Bangladesh

    Directory of Open Access Journals (Sweden)

    M Belayet Hossain

    2017-01-01

    Full Text Available Background: The incidence of different malignancies is increasing among the world populations. Acute lymphoblastic leukaemia (ALL is the most common of all the paediatric malignancies. Response to induction therapy is one of the most important predictors of long term outcome of ALL. Objective: To see the immediate outcome of paediatric ALL patients following induction therapy. Materials and Methods: This retrospective study was conducted from January 2013 to December 2015. Total 221 paediatric ALL patients were included in this study. Diagnosis was based on history, examination, blast cells count on peripheral blood film and bone marrow study, CSF study and immunophenotyping of peripheral blood/bone marrow aspirate in patients who were financially capable. Among them, parents of 40 (18% patients did not agree to start chemotherapy. According to Modified UK ALL 2003 protocol (Regimen A & B 181 patients were given induction therapy (vincristine, prednisolone, L-asparaginase, and daunomycin in high risk patients. Among them 14 patients discontinued, 10 patients died during chemotherapy and rest 157 patients completed induction phase. Bone marrow study was repeated after completion of induction therapy and remission pattern was seen. Results: Out of 157 chemotherapy completed patients, 137 (87% went into complete remission (25% blast cells in the bone marrow. Ten (5.5% patients died due to bleeding, febrile neutropenia and sepsis during the course of induction therapy. Conclusion: ALL in children is curable with effective chemotherapy. Poverty, ignorance and misconception regarding outcome are responsible for refusal and discontinuation of chemotherapy in third world countries like Bangladesh. Mortality and treatment cost can be reduced with the improvement of the facilities for isolation, barrier nursing and supportive treatment, and by creating awareness.

  18. Preparation and characterization of silk fibroin as a biomaterial with potential for drug delivery

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    Zhang Hao

    2012-06-01

    Full Text Available Abstract Background Degummed silk fibroin from Bombyx mori (silkworm has potential carrier capabilities for drug delivery in humans; however, the processing methods have yet to be comparatively analyzed to determine the differential effects on the silk protein properties, including crystalline structure and activity. Methods In this study, we treated degummed silk with four kinds of calcium-alcohol solutions, and performed secondary structure measurements and enzyme activity test to distinguish the differences between the regenerated fibroins and degummed silk fibroin. Results Gel electrophoresis analysis revealed that Ca(NO32-methanol, Ca(NO32-ethanol, or CaCl2-methanol treatments produced more lower molecular weights of silk fibroin than CaCl2-ethanol. X-ray diffraction and Fourier-transform infrared spectroscopy showed that CaCl2-ethanol produced a crystalline structure with more silk I (α-form, type II β-turn, while the other treatments produced more silk II (β-form, anti-parallel β-pleated sheet. Solid-State 13C cross polarization and magic angle spinning-nuclear magnetic resonance measurements suggested that regenerated fibroins from CaCl2-ethanol were nearly identical to degummed silk fibroin, while the other treatments produced fibroins with significantly different chemical shifts. Finally, enzyme activity test indicated that silk fibroins from CaCl2-ethanol had higher activity when linked to a known chemotherapeutic drug, L-asparaginase, than the fibroins from other treatments. Conclusions Collectively, these results suggest that the CaCl2-ethanol processing method produces silk fibroin with biomaterial properties that are appropriate for drug delivery.

  19. A therapeutic trial of decitabine and vorinostat in combination with chemotherapy for relapsed/refractory acute lymphoblastic leukemia.

    Science.gov (United States)

    Burke, Michael J; Lamba, Jatinder K; Pounds, Stanley; Cao, Xueyuan; Ghodke-Puranik, Yogita; Lindgren, Bruce R; Weigel, Brenda J; Verneris, Michael R; Miller, Jeffrey S

    2014-09-01

    DNA hypermethylation and histone deacetylation are pathways of leukemia resistance. We investigated the tolerability and efficacy of decitabine and vorinostat plus chemotherapy in relapse/refractory acute lymphoblastic leukemia (ALL). Decitabine (15 mg/m(2) iv) and vorinostat (230 mg/m(2) PO div BID) were given days 1-4 followed by vincristine, prednisone, PEG-asparaginase, and doxorubicin. Genome wide methylation profiles were performed in 8 matched patient bone marrow (BM) samples taken at day 0 and day 5 (postdecitabine). The median age was 16 (range, 3-54) years. All patients had a prior BM relapse, with five relapsing after allogeneic transplant. The most common nonhematological toxicities possibly related to decitabine or vorinostat were infection with neutropenia (grade 3; n = 4) and fever/neutropenia (grade 3, n = 4; grade 4, n = 1). Of the 13 eligible patients, four achieved complete remission without platelet recovery (CRp), two partial response (PR), one stable disease (SD), one progressive disease (PD), two deaths on study and three patients who did not have end of therapy disease evaluations for an overall response rate of 46.2% (CRp + PR). Following decitabine, significant genome-wide hypo-methylation was observed. Comparison of clinical responders with nonresponders identified methylation profiles of clinical and biological relevance. Decitabine and vorinostat followed by re-Induction chemotherapy was tolerable and demonstrated clinical benefit in relapsed patients with ALL. Methylation differences were identified between responders and nonresponders indicating interpatient variation, which could impact clinical outcome. This study was registered at www.clinicaltrials.gov as NCT00882206.

  20. Dexamethasone compared to prednisolone for adults with acute lymphoblastic leukemia or lymphoblastic lymphoma: final results of the ALL-4 randomized, phase III trial of the EORTC Leukemia Group

    Science.gov (United States)

    Labar, Boris; Suciu, Stefan; Willemze, Roel; Muus, Petra; Marie, Jean-Pierre; Fillet, Georges; Berneman, Zwi; Jaksic, Branimir; Feremans, Walter; Bron, Dominique; Sinnige, Harm; Mistrik, Martin; Vreugdenhil, Gerard; De Bock, Robrecht; Nemet, Damir; Gilotay, Caroline; Amadori, Sergio; de Witte, Theo

    2010-01-01

    Background Corticosteroids are a standard component of the treatment of acute lymphoblastic leukemia and lymphoblastic lymphoma. Our aim was to determine whether dexamethasone results in a better outcome than prednisolone. Design and Methods Adult patients with acute lymphoblastic leukemia or lymphoblastic lymphoma were randomized to receive, as part of their induction therapy on days 1–8 and 15–22, either dexamethasone 8 mg/m2 or prednisolone 60 mg/m2. Those who reached complete remission were given two courses of consolidation therapy with high-dose cytarabine and mitoxantrone and methotrexate and asparaginase. Subsequently patients younger than 50 years, with a suitable donor, were to undergo allogeneic stem cell transplantation, whereas the others were planned to receive either an autologous stem cell transplant or high-dose maintenance chemotherapy with prophylactic central nervous system irradiation. Randomization was done with a minimization technique. The primary endpoint was event-free survival and the analyses was conducted on an intention-to-treat basis. Results Between August 1995 and October 2003, 325 patients between 15 to 72 years of age were randomized to receive either dexamethasone (163 patients) or prednisolone (162 patients). After induction and the course of first consolidation therapy, 131 (80.4%) patients in the dexamethasone group and 124 (76.5%) in the prednisolone group achieved complete remission. No significant difference was observed between the two treatment groups with regards to 6-year event-free survival rates (±SE) which were 25.9% (3.6%) and 28.7% (3.5%) in the dexamethasone and prednisolone groups, respectively (P=0.82, hazard ratio 0.97; 95% confidence interval, 0.75–1.25). Disease-free survival after complete remission was also similar in the dexamethasone and prednisolone groups, the 6-year rates being 32.3% and 37.5%, respectively (hazard ratio 1.03; 95% confidence interval 0.76–1.40). The 6-year cumulative

  1. Research progress of T cell lymphoma: reports from 2014 international conference on T cell lymphoma in clinical treatment%T细胞淋巴瘤研究新进展:2014年国际T细胞淋巴瘤临床治疗大会报道

    Institute of Scientific and Technical Information of China (English)

    马军; 朱军; 石远凯; 姜文奇; 黄慧强; 邱林

    2014-01-01

    The treatment status and progress in T cell lymphoma including epigenetic involved mutations that control DNA and histone methylation were reported and intensively discussed in 2014 international T cell lymphoma forum.According to the theory,treatment with HDAC inhibitor belinostat and romidepsin for peripheral T cell lymphoma (PTCL) can achieve 29 %-38 % overall response rate (ORR) and 13.6 months median relief time.NK/T cell lymphoma in southeast asia is a common malignant lymphoma,15 %-28 % of the NHL accounted in China and Japan for,which is significantly higher than that in the European and American countries,mainly related to EB virus widespread infection.L-asparaginase enzymes,such as SMILE and AspMetDex,can make the early cases with more than 70 % long-term survival rate,advanced cases with 40 % response rate.Some new drugs,such as pralatrexate,combined with romidepsin can be used in PTCL cases to improve the complete remission rate.%2014年国际T细胞淋巴瘤临床大会主要报告了T细胞淋巴瘤的治疗状况及进展,其中包括靶向表观遗传学在T细胞淋巴瘤中的应用.有研究发现在外周T细胞淋巴瘤(PTCL)中控制DNA和组蛋白甲基化的基因存在突变.根据这一研究结果应用组蛋白去乙酰化酶(HDAC)抑制剂belinostat和romidepsin可使PTCL获得29% ~ 38%的总反应率,中位缓解时间为13.6个月.NK/T细胞淋巴瘤是东南亚国家常见的恶性淋巴瘤,在中国和日本占非霍奇金淋巴瘤的15%~ 28%,明显高于欧美国家,主要与亚洲人群EB病毒感染率高有关.应用含左旋门冬酰胺酶的方案如SMILE和AspMetDex方案,可使早期病例长期生存率超过70%,晚期病例可达到近40%.对于PTCL可以将新药如普拉曲沙、罗咪酯肽等联合应用,从而提高完全缓解率.

  2. Evaluation of certain food additives.

    Science.gov (United States)

    2009-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular, flavouring agents). A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (asparaginase from Aspergillus niger expressed in A. niger, calcium lignosulfonate (40-65), ethyl lauroyl arginate, paprika extract, phospholipase C expressed in Pichia pastoris, phytosterols, phytostanols and their esters, polydimethylsiloxane, steviol glycosides and sulfites [assessment of dietary exposure]) and 10 groups of related flavouring agents (aliphatic branched-chain saturated and unsaturated alcohols, aldehydes, acids and related esters; aliphatic linear alpha,beta-unsaturated aldehydes, acids and related alcohols, acetals and esters; aliphatic secondary alcohols, ketones and related esters; alkoxy-substituted allylbenzenes present in foods and essential oils and used as flavouring agents; esters of aliphatic acyclic primary alcohols with aliphatic linear saturated carboxylic acids; furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; hydroxy- and alkoxy-substituted benzyl derivatives; and substances structurally related to menthol). Specifications for the following food additives were revised: canthaxanthin; carob bean gum and carob bean gum (clarified); chlorophyllin copper complexes, sodium and potassium salts; Fast Green FCF; guar gum and guar gum (clarified

  3. SMILE方案治疗复发难治NK/T细胞淋巴瘤的初步临床报告%Preliminary outcomes of patients with relapsed or refractory NK/T-cell lymphoma treated by SMILE regimen

    Institute of Scientific and Technical Information of China (English)

    周颖; 蔡清清; 林旭滨; 高岩; 卜庆; 王潇潇; 黄慧强

    2009-01-01

    目的 探索SMILE方案治疗NK/T细胞淋巴瘤的疗效和不良反应.方法 2006年11月至2008年2月,5例初治和5例复发NK/T细胞淋巴瘤患者接受SMILE方案(甲氨蝶呤、异环磷酰胺、左旋门冬酰胺酶、依托泊苷等)化疗.1例患者进一步接受了自体外周血造血干细胞支持下的超大剂量化疗,2例患者进一步接受局部放疗.结果 10例患者中有8例可以评价疗效,总有效率50%(4/8),无完全缓解.其中初治和复发患者有效率均为50%.主要不良反应为骨髓抑制及氨基转移酶升高,其中Ⅲ~Ⅳ度粒细胞减少占65%,发热性粒细胞减少占25%,Ⅲ度氨基转移酶升高占10%,其他不良反应少见,无治疗相关死亡.26.1%患者由于严重的不良反应中止治疗.结论 SMILE治疗复发耐药的NK/T细胞淋巴瘤有一定疗效,但不良反应明显,目前尚不能作为复发难治NK/T细胞淋巴瘤的标准一线方案.%Objective To evaluate the efficacy and toxicity of SMILE regimen for NK/T-cell lymphoma. Methods From November 2006 to February 2008, 5 patients with relapsed and 5 with first treatment NK/T-cell lymphoma were involved in this study. These patients were treated with SMILE regimen including methotrexate, isofosfamide, L-asparaginase and etoposide.1 patient were treated with autolognus hematopoietic stem cell transplantation (AHSCT), and 2 patients received local regional radiation following SMILE. Results Among 10 patients, 8 were eligible to response evaluation. The overall response rate for whole group was 50 %(4/8) without complete remission. The overall response rate for both previously untreated and relapsed patients were 50 %(2/4). Major toxicity were bone marrow supression and transient transaminase elevation, the incidence of grade Ⅲ -Ⅳ neutroponia was 65 %, and febrile neutropenia was 25 %, Grade Ⅲ transaminase elevation was 10 %. Other toxicities were mild, no treatment-related mortality occurred. 26.1% cycles discontinued due to

  4. DC-CIK方案治疗41例急性白血病清除微小残留病变的疗效%Effect of DC-CIK regimen on minimal residual disease clearance of 41 patients with acute leuke-mia

    Institute of Scientific and Technical Information of China (English)

    宋庆林; 夏瑞雪

    2014-01-01

    目的:分析41例急性白血病微小残留病变的DC-CIK细胞治疗前后实验室检测指标改变特点,探讨其临床治疗意义。方法33例急性髓细胞白血病( AML)患者均经MA方案(米托蒽醌、阿糖胞苷200 mg)或维甲酸/三氧化二砷诱导缓解,2例M2患者采用CAG方案(阿克拉霉素,阿糖胞苷,粒系集落刺激因子300μg/d)诱导缓解,8例急性淋巴细胞白血病患者均经VDCLP方案(长春新碱,柔红霉素,环磷酰胺,左旋门冬酰胺酶,泼尼松)诱导缓解。所有患者应用大剂量强化化疗方案缓解后用 DC-CIK交替维持治疗。结果 DC-CIK治疗后CD3﹢、CD3﹢CD8﹢、CD3﹢CD56﹢/CD16﹢细胞比例明显提高,差异有统计学意义。治疗后白细胞介素( IL)-2、IL-12、IL-17、肿瘤坏死因子-α、干扰素-γ水平提高,而IL-8水平降低,差异有统计学意义。治疗前后微小残留灶WT1的检测显示3例AML 患者治疗前WT1阳性,经DC-CIK 治疗后转阴。IL-17健康对照组最高,未缓解及初治白血病最低,缓解组逐渐升高,DC-CIK治疗后接近正常。结论 DC-CIK免疫治疗急性白血病清除微小残留病变能改善患者免疫抑制状态,提高机体的抗急性白血病免疫效应,有较好的临床疗效。%Objective To analyze the change characteristics of laboratory test indexes before and after treatment with DC-CIK cells for 41 cases of acute leukemia minimal residual disease,and investigate its clinical significance. Methods Thirty-three cases of AML were treated with MA regimen( 200 mg mitoxantrone,Ara)remission induced by arsenic trioxide or retinoic acid,2 cases of M2 were treated with CAG scheme( Accra mycin,cytarabine,granulocyte colony-stimulating factor 300 μg/d)induction of remission,8 cases were treated with VDCLP regimen( vincristine,doxorubicin,cyclophosphamide, prednisone,L-asparaginase,)induced remission. All patients had remission with large dose of